Suspended sediment and carbonate transport in the Yukon River Basin, Alaska: Fluxes and potential future responses to climate change

USGS Publications Warehouse

Dornblaser, Mark M.; Striegl, Robert G.

2009-01-01

Loads and yields of suspended sediment and carbonate were measured and modeled at three locations on the Yukon, Tanana, and Porcupine Rivers in Alaska during water years 2001–2005 (1 October 2000 to 30 September 2005). Annual export of suspended sediment and carbonate upstream from the Yukon Delta averaged 68 Mt a−1 and 387 Gg a−1, respectively, with 50% of the suspended sediment load originating in the Tanana River Basin and 88% of the carbonate load originating in the White River Basin. About half the annual suspended sediment export occurred during spring, and half occurred during summer‐autumn, with very little export in winter. On average, a minimum of 11 Mt a−1 of suspended sediment is deposited in floodplains between Eagle, Alaska, and Pilot Station, Alaska, on an annual basis, mostly in the Yukon Flats. There is about a 27% loss in the carbonate load between Eagle and Yukon River near Stevens Village, with an additional loss of about 29% between Stevens Village and Pilot Station, owing to a combination of deposition and dissolution. Comparison of current and historical suspended sediment loads for Tanana River suggests a possible link between suspended sediment yield and the Pacific decadal oscillation.

Suspended sediment and carbonate transport in the Yukon River Basin, Alaska: Fluxes and potential future responses to climate change

NASA Astrophysics Data System (ADS)

Dornblaser, Mark M.; Striegl, Robert G.

2009-06-01

Loads and yields of suspended sediment and carbonate were measured and modeled at three locations on the Yukon, Tanana, and Porcupine Rivers in Alaska during water years 2001-2005 (1 October 2000 to 30 September 2005). Annual export of suspended sediment and carbonate upstream from the Yukon Delta averaged 68 Mt a-1 and 387 Gg a-1, respectively, with 50% of the suspended sediment load originating in the Tanana River Basin and 88% of the carbonate load originating in the White River Basin. About half the annual suspended sediment export occurred during spring, and half occurred during summer-autumn, with very little export in winter. On average, a minimum of 11 Mt a-1 of suspended sediment is deposited in floodplains between Eagle, Alaska, and Pilot Station, Alaska, on an annual basis, mostly in the Yukon Flats. There is about a 27% loss in the carbonate load between Eagle and Yukon River near Stevens Village, with an additional loss of about 29% between Stevens Village and Pilot Station, owing to a combination of deposition and dissolution. Comparison of current and historical suspended sediment loads for Tanana River suggests a possible link between suspended sediment yield and the Pacific decadal oscillation.

Responses of stream nitrate and DOC loadings to hydrological forcing and climate change in an upland forest of the northeastern United States

NASA Astrophysics Data System (ADS)

Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B.

2009-06-01

In coming decades, higher annual temperatures, increased growing season length, and increased dormant season precipitation are expected across the northeastern United States in response to anthropogenic forcing of global climate. We synthesized long-term stream hydrochemical data from the Sleepers River Research Watershed in Vermont, United States, to explore the relationship of catchment wetness to stream nitrate and DOC loadings. We modeled changes in growing season length and precipitation patterns to simulate future climate scenarios and to assess how stream nutrient loadings respond to climate change. Model results for the 2070-2099 time period suggest that stream nutrient loadings during both the dormant and growing seasons will respond to climate change. During a warmer climate, growing season stream fluxes (runoff +20%, nitrate +57%, and DOC +58%) increase as more precipitation (+28%) and quick flow (+39%) occur during a longer growing season (+43 days). During the dormant season, stream water and nutrient loadings decrease. Net annual stream runoff (+8%) and DOC loading (+9%) increases are commensurate with the magnitude of the average increase of net annual precipitation (+7%). Net annual stream water and DOC loadings are primarily affected by increased dormant season precipitation. In contrast, decreased annual loading of stream nitrate (-2%) reflects a larger effect of growing season controls on stream nitrate and the effects of lengthened growing seasons in a warmer climate. Our findings suggest that leaching of nitrate and DOC from catchment soils will be affected by anthropogenic climate forcing, thereby affecting the timing and magnitude of annual stream loadings in the northeastern United States.

Hydrology, phosphorus, and suspended solids in five agricultural streams in the Lower Fox River and Green Bay Watersheds, Wisconsin, Water Years 2004-06

USGS Publications Warehouse

Graczyk, David J.; Robertson, Dale M.; Baumgart, Paul D.; Fermanich, Kevin J.

2011-01-01

The average annual TSS yields ranged from 111 tons/mi2 in Apple Creek to 45 tons/mi2 in Duck Creek. All five watersheds yielded more TSS than the median value (32.4 tons/mi2) from previous studies in the Southeastern Wisconsin Till Plains (SWTP) ecoregion. The average annual TP yields ranged from 663 lbs/mi2 in Baird Creek to 382 lbs/mi2 in Duck Creek. All five watersheds yielded more TP than the median value from previous studies in the SWTP ecoregion, and the Baird Creek watershed yielded more TP than the statewide median of 650 lbs/mi2 from previous studies.Overall, Duck Creek had the lowest median and volumetric weighted concentrations and mean yield of TSS and TP. The same pattern was true for dissolved phosphorus (DP), except the volumetrically weighted concentration was lowest in the East River. In contrast, Ashwaubenon, Baird, and Apple Creeks had greater median and volumetrically weighted concentrations and mean yields of TSS, TP, DP than Duck Creek and the East River. Water quality in Duck Creek and East River were distinctly different from Ashwaubenon, Baird, and Apple Creeks. Loads from individual runoff events for all of these streams were important to the total annual mass transport of the constituents. On average, about 20 percent of the annual TSS loads and about 17 percent of the TP loads were transported in 1-day events in each stream.

Effects of agricultural nutrient management on nitrogen fate and transport in Lancaster County, Pennsylvania

USGS Publications Warehouse

Hall, D.W.; Risser, D.W.

1993-01-01

Nitrogen inputs to, and outputs from, a 55-acre site in Lancaster County, Pennsylvania, were estimated to determine the pathways and relative magnitude of loads of nitrogen entering and leaving the site, and to compare the loads of nitrogen before and after the implementation of nutrient management. Inputs of nitrogen to the site were manure fertilizer, commercial fertilizer, nitrogen in precipitation, and nitrogen in ground-water inflow; and these sources averaged 93, 4, 2, and 1 percent of average annual nitrogen additions, respectively. Outputs of nitrogen from the site were nitrogen in harvested crops, loads of nitrogen in surface runoff, volatilization of nitrogen, and loads of nitrogen in ground-water discharge, which averaged 37, less than 1,25, and 38 percent of average annual nitrogen removals from the site, respectively. Virtually all of the nitrogen leaving the site that was not removed in harvested crops or by volatilization was discharged in the ground water. Applications of manure and fertilizer nitrogen to 47.5 acres of cropped fields decreased about 33 percent, from an average of 22,700 pounds per year (480 pounds per acre per year) before nutrient management to 15,175 pounds of nitrogen per year (320 pounds per acre per year) after the implementation of nutrient management practices. Nitrogen loads in ground-water discharged from the site decreased about 30 percent, from an average of 292 pounds of nitrogen per million gallons of ground water before nutrient management to an average of 203 pounds of nitrogen per million gallons as a result of the decreased manure and commercial fertilizer applications. Reductions in manure and commercial fertilizer applications caused a reduction of approximately 11,000 pounds (3,760 pounds per year, 70 pounds per acre per year) in the load of nitrogen discharged in ground water from the 55-acre site during the three-year period 1987-1990.

RELATIONSHIPS BETWEEEN NITROGEN LOADING AND CONCENTRATIONS OF NITROGEN AND CHLOROPHYLL IN COASTAL EMBAYMENTS

EPA Science Inventory

We describe results obtained with a simple model that uses loading rates of total nitrogen (TN), defined as dissolved inorganic nitrogen plus dissolved and particulate organic nitrogen, to calculate annually and spatially averaged concentrations of TN in coastal embayments. We al...

A MODEL OF ESTUARY RESPONSE TO NITROGEN LOADING AND FRESHWATER RESIDENCE TIME

EPA Science Inventory

We have developed a deterministic model that relates average annual nitrogen loading rate and water residence time in an estuary to in-estuary nitrogen concentrations and loss rates (e.g. denitrification and incorporation in sediments), and to rates of nitrogen export across the ...

Combine the soil water assessment tool (SWAT) with sediment geochemistry to evaluate diffuse heavy metal loadings at watershed scale.

PubMed

Jiao, Wei; Ouyang, Wei; Hao, Fanghua; Huang, Haobo; Shan, Yushu; Geng, Xiaojun

2014-09-15

Assessing the diffuse pollutant loadings at watershed scale has become increasingly important when formulating effective watershed water management strategies, but the process was seldom achieved for heavy metals. In this study, the overall temporal-spatial variability of particulate Pb, Cu, Cr and Ni losses within an agricultural watershed was quantitatively evaluated by combining SWAT with sediment geochemistry. Results showed that the watershed particulate heavy metal loadings displayed strong variability in the simulation period 1981-2010, with an obvious increasing trend in recent years. The simulated annual average loadings were 20.21 g/ha, 21.75 g/ha, 47.35 g/ha and 21.27 g/ha for Pb, Cu, Cr and Ni, respectively. By comparison, these annual average values generally matched the estimated particulate heavy metal loadings at field scale. With spatial interpolation of field loadings, it was found that the diffuse heavy metal pollution mainly came from the sub-basins dominated with cultivated lands, accounting for over 70% of total watershed loadings. The watershed distribution of particulate heavy metal losses was very similar to that of soil loss but contrary to that of heavy metal concentrations in soil, highlighting the important role of sediment yield in controlling the diffuse heavy metal loadings. Copyright © 2014 Elsevier B.V. All rights reserved.

Quantifying suspended sediment loads delivered to Cheney Reservoir, Kansas: Temporal patterns and management implications

USGS Publications Warehouse

Stone, Mandy L.; Juracek, Kyle E.; Graham, Jennifer L.; Foster, Guy

2015-01-01

Cheney Reservoir, constructed during 1962 to 1965, is the primary water supply for the city of Wichita, the largest city in Kansas. Sediment is an important concern for the reservoir as it degrades water quality and progressively decreases water storage capacity. Long-term data collection provided a unique opportunity to estimate the annual suspended sediment loads for the entire history of the reservoir. To quantify and characterize sediment loading to Cheney Reservoir, discrete suspended sediment samples and continuously measured streamflow data were collected from the North Fork Ninnescah River, the primary inflow to Cheney Reservoir, over a 48-year period. Continuous turbidity data also were collected over a 15-year period. These data were used together to develop simple linear regression models to compute continuous suspended sediment concentrations and loads from 1966 to 2013. The inclusion of turbidity as an additional explanatory variable with streamflow improved regression model diagnostics and increased the amount of variability in suspended sediment concentration explained by 14%. Using suspended sediment concentration from the streamflow-only model, the average annual suspended sediment load was 102,517 t (113,006 tn) and ranged from 4,826 t (5,320 tn) in 1966 to 967,569 t (1,066,562 tn) in 1979. The sediment load in 1979 accounted for about 20% of the total load over the 48-year history of the reservoir and 92% of the 1979 sediment load occurred in one 24-hour period during a 1% annual exceedance probability flow event (104-year flood). Nearly 60% of the reservoir sediment load during the 48-year study period occurred in 5 years with extreme flow events (9% to 1% annual exceedance probability, or 11- to 104-year flood events). A substantial portion (41%) of sediment was transported to the reservoir during five storm events spanning only eight 24-hour periods during 1966 to 2013. Annual suspended sediment load estimates based on streamflow were, on average, within ±20% of estimates based on streamflow and turbidity combined. Results demonstrate that large suspended sediment loads are delivered to Cheney Reservoir in very short time periods, indicating that sediment management plans eventually must address large, infrequent inflow events to be effective.

Responses of stream nitrate and dissolved organic carbon loadings to hydrological forcing and climate change in an upland forest of the northeast USA

USGS Publications Warehouse

Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B.

2009-01-01

[1] In coming decades, higher annual temperatures, increased growing season length, and increased dormant season precipitation are expected across the northeastern United States in response to anthropogenic forcing of global climate. We synthesized long-term stream hydrochemical data from the Sleepers River Research Watershed in Vermont, United States, to explore the relationship of catchment wetness to stream nitrate and DOC loadings. We modeled changes in growing season length and precipitation patterns to simulate future climate scenarios and to assess how stream nutrient loadings respond to climate change. Model results for the 2070–2099 time period suggest that stream nutrient loadings during both the dormant and growing seasons will respond to climate change. During a warmer climate, growing season stream fluxes (runoff +20%, nitrate +57%, and DOC +58%) increase as more precipitation (+28%) and quick flow (+39%) occur during a longer growing season (+43 days). During the dormant season, stream water and nutrient loadings decrease. Net annual stream runoff (+8%) and DOC loading (+9%) increases are commensurate with the magnitude of the average increase of net annual precipitation (+7%). Net annual stream water and DOC loadings are primarily affected by increased dormant season precipitation. In contrast, decreased annual loading of stream nitrate (−2%) reflects a larger effect of growing season controls on stream nitrate and the effects of lengthened growing seasons in a warmer climate. Our findings suggest that leaching of nitrate and DOC from catchment soils will be affected by anthropogenic climate forcing, thereby affecting the timing and magnitude of annual stream loadings in the northeastern United States.

Responses of stream nitrate and DOC loadings to hydrological forcing and climate change in an upland forest of the northeastern United States

USGS Publications Warehouse

Sebestyen, S.D.; Boyer, E.W.; Shanley, J.B.

2009-01-01

In coming decades, higher annual temperatures, increased growing season length, and increased dormant season precipitation are expected across the northeastern United States in response to anthropogenic forcing of global climate. We synthesized long-term stream hydrochemical data from the Sleepers River Research Watershed in Vermont, United States, to explore the relationship of catchment wetness to stream nitrate and DOC loadings. We modeled changes in growing season length and precipitation patterns to simulate future climate scenarios and to assess how stream nutrient loadings respond to climate change. Model results for the 2070-2099 time period suggest that stream nutrient loadings during both the dormant and growing seasons will respond to climate change. During a warmer climate, growing season stream fluxes (runoff+20%, nitrate +57%, and DOC +58%) increase as more precipitation (+28%) and quick flow (+39%) occur during a longer growing season (+43 days). During the dormant season, stream water and nutrient loadings decrease. Net annual stream runoff (+8%) and DOC loading (+9%) increases are commensurate with the magnitude of the average increase of net annual precipitation (+7%). Net annual stream water and DOC loadings are primarily affected by increased dormant season precipitation. In contrast, decreased annual loading of stream nitrate (-2%) reflects a larger effect of growing season controls on stream nitrate and the effects of lengthened growing seasons in a warmer climate. Our findings suggest that leaching of nitrate and DOC from catchment soils will be affected by anthropogenic climate forcing, thereby affecting the timing and magnitude of annual stream loadings in the northeastern United States. Copyright 2009 by the American Geophysical Union.

Annual Nutrient Loadings, Primary Productivity, and Trophic State of Lake Koocanusa, Montana and British Columbia, 1972-80

USGS Publications Warehouse

Woods, Paul F.

1982-01-01

Limnological data collected at Lake Koocanusa were used to investigate the relationship of nutrient loadings, primary productivity, and trophic state of the reservoir during 1972-80. The reservoir, on the Kootenai River, was impounded by Libby Dam on March 21, 1972. Manipulation of the 7.16-cubic-kilometer reservoir for flood control, its primary function, created large fluctuations in reservoir volume and produced annual lake-filling times that ranged from 0.14 to 0.66 year. Loadings of nitrogen and phosphorus prior to and following impoundment of Lake Koocanusa were found to be large enough to predict eutrophic conditions. Beginning in 1976, total phosphorus loadings, but not total nitrogen loadings, were substantially reduced following improvements in waste-water treatment at a fertilizer plant located upstream from the reservoir. The closure of Libby Dam substantially reduced loadings of nitrogen and phosphorus downstream from Lake Koocanusa. On the average, the reservoir retained 63 percent of its influent loading of total phosphorus and 25 percent of its influent loading of total nitrogen. Daily areal and volumetric primary productivity varied widely in each year at four sampled limnological stations. During the 9 years studied, daily areal primary productivity, in milligrams of carbon fixed per square meter, ranged from 0.4 to 420.0; the mean of the 313 sampled days was 128.5. Annual areal primary productivity ranged from 23.2 to 38.5 grams of carbon fixed per square meter and thereby categorized Lake Koocanusa as oligotrophic. The relationship of annual areal primary productivity and 12 selected environmental variables was determined by multiple regression analysis. One of the models that was derived used two variables-annual euphotic zone depth and annual areal phosphorus loading-and accounted for 62.0 percent of the variation in annual areal primary productivity. The distribution of chlorophyll a within the water column indicated that, on the average, more than one-half of the phytoplankton in the reservoir was beneath the euphotic zone. These results support the hypothesis that the reservoir's weak thermal structure had allowed circulation of phytoplankton out of the euphotic zone. The trophic state of Lake Koocanusa was categorized as eutrophic when based on the relationship of the nutrient loadings and the reservoir's ratio of mean depth to hydraulic-residence time. This result conflicted with the oligotrophic ranking the reservoir received based on its areal primary productivity. The discrepancy in trophic state was attributed mainly to the failure of nutrient loading models to adequately account for physical processes within reservoirs. Part of the nutrient loading that entered Lake Koocanusa was unavailable to phytoplankton because the nutrients were carried beneath the euphotic zone by large volumes of interflow and underflow. Another part of the nutrient loading was adsorbed to suspended sediment and removed from the water column. Thus, phytoplankton primary productivity was controlled not only by nutrients, but also by other limno logical processes.

40 CFR 63.11224 - What are my monitoring, installation, operation, and maintenance requirements?

Code of Federal Regulations, 2014 CFR

2014-07-01

... include a daily calibration drift assessment, a quarterly performance audit, and an annual zero alignment... performance audit, or an annual zero alignment audit. (7) You must calculate and record 6-minute averages from... absolute particulate matter loadings. (5) The bag leak detection system must be equipped with a device to...

40 CFR 63.11224 - What are my monitoring, installation, operation, and maintenance requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

... include a daily calibration drift assessment, a quarterly performance audit, and an annual zero alignment... performance audit, or an annual zero alignment audit. (7) You must calculate and record 6-minute averages from... absolute particulate matter loadings. (5) The bag leak detection system must be equipped with a device to...

EFFECT OF RESIDENCE TIME ON ANNUAL EXPORT AND DENITRIFICATION OF NITROGEN IN ESTUARIES: A MODEL ANALYSIS

EPA Science Inventory

A simple model of annual average response of an estuary to mean nitrogen loading rate and freshwater residence time was developed and tested. It uses nitrogen inputs from land, deposition from the atmosphere, and first-order calculations of internal loss rate and export to perfor...

Estimation of constituent concentrations, densities, loads, and yields in lower Kansas River, northeast Kansas, using regression models and continuous water-quality monitoring, January 2000 through December 2003

USGS Publications Warehouse

Rasmussen, Teresa J.; Ziegler, Andrew C.; Rasmussen, Patrick P.

2005-01-01

The lower Kansas River is an important source of drinking water for hundreds of thousands of people in northeast Kansas. Constituents of concern identified by the Kansas Department of Health and Environment (KDHE) for streams in the lower Kansas River Basin include sulfate, chloride, nutrients, atrazine, bacteria, and sediment. Real-time continuous water-quality monitors were operated at three locations along the lower Kansas River from July 1999 through September 2004 to provide in-stream measurements of specific conductance, pH, water temperature, turbidity, and dissolved oxygen and to estimate concentrations for constituents of concern. Estimates of concentration and densities were combined with streamflow to calculate constituent loads and yields from January 2000 through December 2003. The Wamego monitoring site is located 44 river miles upstream from the Topeka monitoring site, which is 65 river miles upstream from the DeSoto monitoring site, which is 18 river miles upstream from where the Kansas River flows into the Missouri River. Land use in the Kansas River Basin is dominated by grassland and cropland, and streamflow is affected substantially by reservoirs. Water quality at the three monitoring sites varied with hydrologic conditions, season, and proximity to constituent sources. Nutrient and sediment concentrations and bacteria densities were substantially larger during periods of increased streamflow, indicating important contributions from nonpoint sources in the drainage basin. During the study period, pH remained well above the KDHE lower criterion of 6.5 standard units at all sites in all years, but exceeded the upper criterion of 8.5 standard units annually between 2 percent of the time (Wamego in 2001) and 65 percent of the time (DeSoto in 2003). The dissolved oxygen concentration was less than the minimum aquatic-life-support criterion of 5.0 milligrams per liter less than 1 percent of the time at all sites. Dissolved solids, a measure of the dissolved material in water, exceeded 500 milligrams per liter about one-half of the time at the three Kansas River sites. Larger dissolved-solids concentrations upstream likely were a result of water inflow from the highly mineralized Smoky Hill River that is diluted by tributary flow as it moves downstream. Concentrations of total nitrogen and total phosphorus at the three monitoring sites exceeded the ecoregion water-quality criteria suggested by the U.S. Environmental Protection Agency during the entire study period. Median nitrogen and phosphorus concentrations were similar at all three sites, and nutrient load increased moving from the upstream to downstream sites. Total nitrogen and total phosphorus yields were nearly the same from site to site indicating that nutrient sources were evenly distributed throughout the lower Kansas River Basin. About 11 percent of the total nitrogen load and 12 percent of the total phosphorus load at DeSoto during 2000-03 originated from wastewater-treatment facilities. Escherichia coli bacteria densities were largest at the middle site, Topeka. On average, 83 percent of the annual bacteria load at DeSoto during 2000-03 occurred during 10 percent of the time, primarily in conjunction with runoff. The average annual sediment loads at the middle and downstream monitoring sites (Topeka and DeSoto) were nearly double those at the upstream site (Wamego). The average annual sediment yield was largest at Topeka. On average, 64 percent of the annual suspended-sediment load at DeSoto during 2000-03 occurred during 10 percent of the time. Trapping of sediment by reservoirs located on contributing tributaries decreases transport of sediment and sediment-related constituents. The average annual suspended-sediment load in the Kansas River at DeSoto during 2000-03 was estimated at 1.66 million tons. An estimated 13 percent of this load consisted of sand-size particles, so approximately 216,000 tons of sand were transported

2014 Gulf of Mexico Hypoxia Forecast

USGS Publications Warehouse

Scavia, Donald; Evans, Mary Anne; Obenour, Dan

2014-01-01

The Gulf of Mexico annual summer hypoxia forecasts are based on average May total nitrogen loads from the Mississippi River basin for that year. The load estimate, recently released by USGS, is 4,761 metric tons per day. Based on that estimate, we predict the area of this summer’s hypoxic zone to be 14,000 square kilometers (95% credible interval, 8,000 to 20,000) – an “average year”. Our forecast hypoxic volume is 50 km3 (95% credible interval, 20 to 77).

Influence of various water quality sampling strategies on load estimates for small streams

USGS Publications Warehouse

Robertson, Dale M.; Roerish, Eric D.

1999-01-01

Extensive streamflow and water quality data from eight small streams were systematically subsampled to represent various water‐quality sampling strategies. The subsampled data were then used to determine the accuracy and precision of annual load estimates generated by means of a regression approach (typically used for big rivers) and to determine the most effective sampling strategy for small streams. Estimation of annual loads by regression was imprecise regardless of the sampling strategy used; for the most effective strategy, median absolute errors were ∼30% based on the load estimated with an integration method and all available data, if a regression approach is used with daily average streamflow. The most effective sampling strategy depends on the length of the study. For 1‐year studies, fixed‐period monthly sampling supplemented by storm chasing was the most effective strategy. For studies of 2 or more years, fixed‐period semimonthly sampling resulted in not only the least biased but also the most precise loads. Additional high‐flow samples, typically collected to help define the relation between high streamflow and high loads, result in imprecise, overestimated annual loads if these samples are consistently collected early in high‐flow events.

Magnitudes, nature, and effects of point and nonpoint discharges in the Chattahoochee River basin, Atlanta to West Point Dam, Georgia

USGS Publications Warehouse

Stamer, J.K.; Cherry, R.N.; Faye, R.E.; Kleckner, R.L.

1978-01-01

On an average annual basis and during the storm period of March 12-15, 1976, nonpoint-source loads for most constituents were larger than point-source loads at the Whitesburg station, located on the Chattahoochee River about 40 miles downstream from Atlanta, GA. Most of the nonpoint-source constituent loads in the Atlanta to Whitesburg reach were from urban areas. Average annual point-source discharges accounted for about 50 percent of the dissolved nitrogen, total nitrogen, and total phosphorus loads and about 70 percent of the dissolved phosphorus loads at Whitesburg. During a low-flow period, June 1-2, 1977, five municipal point-sources contributed 63 percent of the ultimate biochemical oxygen demand, and 97 percent of the ammonium nitrogen loads at the Franklin station, at the upstream end of West Point Lake. Dissolved-oxygen concentrations of 4.1 to 5.0 milligrams per liter occurred in a 22-mile reach of the river downstream from Atlanta due about equally to nitrogenous and carbonaceous oxygen demands. The heat load from two thermoelectric powerplants caused a decrease in dissolved-oxygen concentration of about 0.2 milligrams per liter. Phytoplankton concentrations in West Point Lake, about 70 miles downstream from Atlanta, could exceed three million cells per millimeter during extended low-flow periods in the summer with present point-source phosphorus loads. (Woodard-USGS)

Nutrient and Suspended-Sediment Transport and Trends in the Columbia River and Puget Sound Basins, 1993-2003

USGS Publications Warehouse

Wise, Daniel R.; Rinella, Frank A.; Rinella, Joseph F.; Fuhrer, Greg J.; Embrey, Sandra S.; Clark, Gregory M.; Schwarz, Gregory E.; Sobieszczyk, Steven

2007-01-01

This study focused on three areas that might be of interest to water-quality managers in the Pacific Northwest: (1) annual loads of total nitrogen (TN), total phosphorus (TP) and suspended sediment (SS) transported through the Columbia River and Puget Sound Basins, (2) annual yields of TN, TP, and SS relative to differences in landscape and climatic conditions between subbasin catchments (drainage basins), and (3) trends in TN, TP, and SS concentrations and loads in comparison to changes in landscape and climatic conditions in the catchments. During water year 2000, an average streamflow year in the Pacific Northwest, the Columbia River discharged about 570,000 pounds per day of TN, about 55,000 pounds per day of TP, and about 14,000 tons per day of SS to the Pacific Ocean. The Snake, Yakima, Deschutes, and Willamette Rivers contributed most of the load discharged to the Columbia River. Point-source nutrient loads to the catchments (almost exclusively from municipal wastewater treatment plants) generally were a small percentage of the total in-stream nutrient loads; however, in some reaches of the Spokane, Boise, Walla Walla, and Willamette River Basins, point sources were responsible for much of the annual in-stream nutrient load. Point-source nutrient loads generally were a small percentage of the total catchment nutrient loads compared to nonpoint sources, except for a few catchments where point-source loads comprised as much as 30 percent of the TN load and as much as 80 percent of the TP load. The annual TN and TP loads from point sources discharging directly to the Puget Sound were about equal to the annual loads from eight major tributaries. Yields of TN, TP, and SS generally were greater in catchments west of the Cascade Range. A multiple linear regression analysis showed that TN yields were significantly (p < 0.05) and positively related to precipitation, atmospheric nitrogen load, fertilizer and manure load, and point-source load, and were negatively related to average slope. TP yields were significantly related positively to precipitation, and point-source load and SS yields were significantly related positively to precipitation. Forty-eight percent of the available monitoring sites for TN had significant trends in concentration (2 increasing, 19 decreasing), 32 percent of the available sites for TP had significant trends in concentration (7 increasing, 9 decreasing), and 40 percent of the available sites for SS had significant trends in concentration (4 increasing, 15 decreasing). The trends in load followed a similar pattern, but with fewer sites showing significant trends. The results from this study indicate that inputs from nonpoint sources of nutrients probably have decreased over time in many of the catchments. Despite the generally small contribution of point-source nutrient loads, they still may have been partially responsible for the significant decreasing trends for nutrients at sites where the total point-source nutrient loads to the catchments equaled a substantial proportion of the in-stream load.

Pre-development conditions to assess the impact of growth in an urbanizing watershed in Northern Virginia

NASA Astrophysics Data System (ADS)

Kumar, Saurav; Godrej, Adil N.; Grizzard, Thomas J.

2016-09-01

Pre-development conditions are an easily understood state to which watershed nonpoint nutrient reduction targets may be referenced. Using the pre-development baseline, a "developed-excess" measure may be computed for changes due to anthropogenic development. Developed-excess is independent of many geographical, physical, and hydrological characteristics of the region and after normalization by area may be used for comparison among various sub-sets of the watershed, such as jurisdictions or land use types. We have demonstrated this method by computing pre-development nitrogen and phosphorus loads entering the Occoquan Reservoir from its tributary watershed in Northern Virginia. The pre-development loads in this study were computed using the calibrated water quality models for the period 2002-2007. Current forest land was used as a surrogate for pre-development land use conditions for the watershed and developed-excess was estimated for fluvial loads of Total Inorganic Nitrogen (TIN) and Orthophosphate-Phosphorus (OP) by subtracting simulated predevelopment loads from observed loads. It was observed that within the study period (2002-2007), the average annual developed-excess represented about 30% of the TIN and OP average annual loads exported to the reservoir. Comparison of the two disturbed land use types, urban and agricultural, showed that urban land uses exported significantly more excess nonpoint nutrient load per unit area than agricultural land uses.

Annual replenishment of bed material by sediment transport in the Wind River near Riverton, Wyoming

USGS Publications Warehouse

Smalley, M.L.; Emmett, W.W.; Wacker, A.M.

1994-01-01

The U.S. Geological Survey, in cooperation with the Wyoming Department of Transportation, conducted a study during 1985-87 to determine the annual replenishment of sand and gravel along a point bar in the Wind River near Riverton, Wyoming. Hydraulic- geometry relations determined from streamflow measurements; streamflow characteristics determined from 45 years of record at the study site; and analyses of suspended-sediment, bedload, and bed- material samples were used to describe river transport characteristics and to estimate the annual replenishment of sand and gravel. The Wind River is a perennial, snowmelt-fed stream. Average daily discharge at the study site is about 734 cubic feet per second, and bankfull discharge (recurrence interval about 1.5 years) is about 5,000 cubic feet per second. At bankfull discharge, the river is about 136 feet wide and has an average depth of about 5.5 feet and average velocity of about 6.7 feet per second. Streams slope is about 0.0010 foot per foot. Bed material sampled on the point bar before the 1986 high flows ranged from sand to cobbles, with a median diameter of about 22 millimeters. Data for sediment samples collected during water year 1986 were used to develop regression equations between suspended-sediment load and water discharge and between bedload and water discharge. Average annual suspended-sediment load was computed to be about 561,000 tons per year using the regression equation in combination with flow-duration data. The regression equation for estimating bedload was not used; instead, average annual bedload was computed as 1.5 percent of average annual suspended load about 8,410 tons per year. This amount of bedload material is estimated to be in temporary storage along a reach containing seven riffles--a length of approximately 1 river mile. On the basis of bedload material sampled during the 1986 high flows, about 75 percent (by weight) is sand (2 millimeters in diameter or finer); median particle size is about 0.5 milli- meter. About 20 percent (by weight) is medium gravel to small cobbles--12.7 millimeters (0.5 inch) or coarser. The bedload moves slowly (about 0.03 percent of the water speed) and briefly (about 10 percent of the time). The average travel distance of a median-sized particle is about 1 river mile per year. The study results indicate that the average replenishment rate of bedload material coarser than 12.7 millimeters is about 1,500 to 2,000 tons (less than 1,500 cubic yards) per year. Finer material (0.075 to 6.4 millimeters in diameter) is replen- ishment at about 4,500 to 5,000 cubic yards per year. The total volume of potentially usable material would average about 6,000 cubic yards per year.

Estimating total maximum daily loads with the Stochastic Empirical Loading and Dilution Model

USGS Publications Warehouse

Granato, Gregory; Jones, Susan Cheung

2017-01-01

The Massachusetts Department of Transportation (DOT) and the Rhode Island DOT are assessing and addressing roadway contributions to total maximum daily loads (TMDLs). Example analyses for total nitrogen, total phosphorus, suspended sediment, and total zinc in highway runoff were done by the U.S. Geological Survey in cooperation with FHWA to simulate long-term annual loads for TMDL analyses with the stochastic empirical loading and dilution model known as SELDM. Concentration statistics from 19 highway runoff monitoring sites in Massachusetts were used with precipitation statistics from 11 long-term monitoring sites to simulate long-term pavement yields (loads per unit area). Highway sites were stratified by traffic volume or surrounding land use to calculate concentration statistics for rural roads, low-volume highways, high-volume highways, and ultraurban highways. The median of the event mean concentration statistics in each traffic volume category was used to simulate annual yields from pavement for a 29- or 30-year period. Long-term average yields for total nitrogen, phosphorus, and zinc from rural roads are lower than yields from the other categories, but yields of sediment are higher than for the low-volume highways. The average yields of the selected water quality constituents from high-volume highways are 1.35 to 2.52 times the associated yields from low-volume highways. The average yields of the selected constituents from ultraurban highways are 1.52 to 3.46 times the associated yields from high-volume highways. Example simulations indicate that both concentration reduction and flow reduction by structural best management practices are crucial for reducing runoff yields.

Estimating Oxygen Needs for Childhood Pneumonia in Developing Country Health Systems: A New Model for Expecting the Unexpected

PubMed Central

Bradley, Beverly D.; Howie, Stephen R. C.; Chan, Timothy C. Y.; Cheng, Yu-Ling

2014-01-01

Background Planning for the reliable and cost-effective supply of a health service commodity such as medical oxygen requires an understanding of the dynamic need or ‘demand’ for the commodity over time. In developing country health systems, however, collecting longitudinal clinical data for forecasting purposes is very difficult. Furthermore, approaches to estimating demand for supplies based on annual averages can underestimate demand some of the time by missing temporal variability. Methods A discrete event simulation model was developed to estimate variable demand for a health service commodity using the important example of medical oxygen for childhood pneumonia. The model is based on five key factors affecting oxygen demand: annual pneumonia admission rate, hypoxaemia prevalence, degree of seasonality, treatment duration, and oxygen flow rate. These parameters were varied over a wide range of values to generate simulation results for different settings. Total oxygen volume, peak patient load, and hours spent above average-based demand estimates were computed for both low and high seasons. Findings Oxygen demand estimates based on annual average values of demand factors can often severely underestimate actual demand. For scenarios with high hypoxaemia prevalence and degree of seasonality, demand can exceed average levels up to 68% of the time. Even for typical scenarios, demand may exceed three times the average level for several hours per day. Peak patient load is sensitive to hypoxaemia prevalence, whereas time spent at such peak loads is strongly influenced by degree of seasonality. Conclusion A theoretical study is presented whereby a simulation approach to estimating oxygen demand is used to better capture temporal variability compared to standard average-based approaches. This approach provides better grounds for health service planning, including decision-making around technologies for oxygen delivery. Beyond oxygen, this approach is widely applicable to other areas of resource and technology planning in developing country health systems. PMID:24587089

Streamflow and nutrient data for the Yazoo River below Steele Bayou near Long Lake, Mississippi, 1996-2000

USGS Publications Warehouse

Runner, Michael S.; Turnipseed, D. Phil; Coupe, Richard H.

2002-01-01

Increased nutrient loading to the Gulf of Mexico from off-continent flux has been identified as contributing to the increase in the areal extent of the low dissolved-oxygen zone that develops annually off the Louisiana and Texas coast. The proximity of the Yazoo River Basin in northwestern Mississippi to the Gulf of Mexico, and the intensive agricultural activities in the basin have led to speculation that the Yazoo River Basin contributes a disproportionate amount of nitrogen and phosphorus to the Mississippi River and ultimately to the Gulf of Mexico. An empirical measurement of the flux of nitrogen and phosphorus from the Yazoo Basin has not been possible due to the hydrology of the lower Yazoo River Basin. Streamflow for the Yazoo River below Steele Bayou is affected by backwater from the Mississippi River. Flow at the gage is non-uniform and varying, with bi-directional and reverse flows possible. Streamflow was computed by using remote sensing and acoustic and conventional discharge and velocity measurement techniques. Streamflow from the Yazoo River for the 1996-2000 period accounted for 2.8 percent of the flow of the Mississippi River for the same period. Water samples from the Yazoo River were collected from February 1996 through December 2000 and were analyzed for total nitrogen, nitrate, total phosphorus, and orthophosphorus as part of the U.S. Geological Survey National Water-Quality Assessment Program. These data were used to compute annual loads of nitrogen and phosphorus discharged from the Yazoo River for the period 1996-2000. Annual loads of nitrogen and phosphorus were calculated by two methods. The first method used multivariate regression and the second method multiplied the mean annual concentration by the total annual flow. Load estimates based on the product of the mean annual concentration and the total annual flow were within the 95 percent confidence interval for the load calculated by multivariate regression in 10 of 20 cases. The Yazoo River loads, compared to average annual loads in the Mississippi River, indicated that the Yazoo River was contributing 1.4 percent of the total nitrogen load, 0.7 percent of the nitrate load, 3.4 percent of the total phosphorus load, and 1.6 percent of the orthophosphorus load during 1996 - 2000. The total nitrogen, nitrate, and orthophosphorus loads in the Yazoo River Basin were less than expected, whereas the total phosphorus load was slightly higher than expected based on discharge.

Suspended-sediment loads from major tributaries to the Missouri River between Garrison Dam and Lake Oahe, North Dakota, 1954-98

USGS Publications Warehouse

Macek-Rowland, Kathleen M.

2000-01-01

Annual suspended-sediment loads for water years 1954 through 1998 were estimated for the major tributaries in the Missouri River Basin between Garrison Dam and Lake Oahe in North Dakota and for the Missouri River at Garrison Dam and the Missouri River at Bismarck, N. Dak.  The major tributaries are the Knife River, Turtle Creek, Painted Woods Creek, Square Butte Creek, Burnt Creek, Heart River, and Apple Creek.  Sediment and streamflow data used to estimate the suspended-sediment loads were from selected U.S. Geological Survey streamflow-gaging stations located within each basin.  Some of the stations had no sediment data available and limited continuous streamflow data for water years 1954 through 1998.  Therefore, data from nearby streamflow-gaging stations were assumed for the calculations. The Heart River contributed the largest amount of suspended sediment to the Missouri River for 1954-98.  Annual suspended-sediment loads in the Heart River near Mandan ranged from less than 1 to 40 percent of the annual suspended-sediment load in the Missouri River. The Knife River contributed the second largest amount of suspended sediment to the Missouri River.  Annual suspended-sediment loads in the Knife River at Hazen ranged from less than 1 to 19 percent of the annual suspended-sediment load in the Missouri River.  Apple Creek, Turtle Creek, Painted Woods Creek, Square Butte Creek, and Burnt Creek all contributed 2 percent or less of the annual suspended-sediment load in the Missouri River.  The Knife River and the Heart River also had the largest average suspended-sediment yields for the seven tributaries.  The yield for the Knife River was 91.1 tons per square mile, and the yield for the Heart River was 133 tons per square mile.  The remaining five tributaries had yields of less than 24 tons per square mile based on total drainage area. 

Organic compounds and cadmium in the tributaries to the Elizabeth River in New Jersey, October 2008 to November 2008: Phase II of the New Jersey Toxics Reduction Workplan for New York-New Jersey Harbor

USGS Publications Warehouse

Bonin, Jennifer L.

2010-01-01

Samples of surface water and suspended sediment were collected from the two branches that make up the Elizabeth River in New Jersey - the West Branch and the Main Stem - from October to November 2008 to determine the concentrations of selected chlorinated organic and inorganic constituents. The sampling and analyses were conducted as part of Phase II of the New York-New Jersey Harbor Estuary Plan-Contaminant Assessment and Reduction Program (CARP), which is overseen by the New Jersey Department of Environmental Protection. Phase II of the New Jersey Workplan was conducted by the U.S. Geological Survey to define upstream tributary and point sources of contaminants in those rivers sampled during Phase I work, with special emphasis on the Passaic and Elizabeth Rivers. This portion of the Phase II study was conducted on the two branches of the Elizabeth River, which were previously sampled during July and August of 2003 at low-flow conditions. Samples were collected during 2008 from the West Branch and Main Stem of the Elizabeth River just upstream from their confluence at Hillside, N.J. Both tributaries were sampled once during low-flow discharge conditions and once during high-flow discharge conditions using the protocols and analytical methods that were used in the initial part of Phase II of the Workplan. Grab samples of streamwater also were collected at each site and were analyzed for cadmium, suspended sediment, and particulate organic carbon. The measured concentrations, along with available historical suspended-sediment and stream-discharge data were used to estimate average annual loads of suspended sediment and organic compounds in the two branches of the Elizabeth River. Total suspended-sediment loads for 1975 to 2000 were estimated using rating curves developed from historical U.S. Geological Survey suspended-sediment and discharge data, where available. Concentrations of suspended-sediment-bound polychlorinated biphenyls (PCBs) in the Main Stem and the West Branch of the Elizabeth River during low-flow conditions were 534 ng/g (nanograms per gram) and 1,120 ng/g, respectively, representing loads of 27 g/yr (grams per year) and 416 g/yr, respectively. These loads were estimated using contaminant concentrations during low flow, and the assumed 25-year average discharge, and 25-year average suspended-sediment concentration. Concentrations of suspended-sediment-bound PCBs in the Main Stem and the West Branch of the Elizabeth River during high-flow conditions were 3,530 ng/g and 623 ng/g, respectively, representing loads of 176 g/yr and 231 g/yr, respectively. These loads were estimated using contaminant concentrations during high-flow conditions, the assumed 25-year average discharge, and 25-year average suspended-sediment concentration. Concentrations of suspended-sediment-bound polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-difuran compounds (PCDD/PCDFs) during low-flow conditions were 2,880 pg/g (picograms per gram) and 5,910 pg/g in the Main Stem and West Branch, respectively, representing average annual loads of 0.14 g/yr and 2.2 g/yr, respectively. Concentrations of suspended-sediment-bound PCDD/PCDFs during high-flow conditions were 40,900 pg/g and 12,400 pg/g in the Main Stem and West Branch, respectively, representing average annual loads of 2.05 g/yr and 4.6 g/yr, respectively. Total toxic equivalency (TEQ) loads (sum of PCDD/PCDF and PCB TEQs) were 3.1 mg/yr (milligrams per year) (as 2, 3, 7, 8-TCDD) in the Main Stem and 28 mg/yr in the West Branch during low-flow conditions. Total TEQ loads (sum of PCDD/PCDFs and PCBs) were 27 mg/yr (as 2, 3, 7, 8-TCDD) in the Main Stem and 32 mg/yr in the West Branch during high-flow conditions. All of these load estimates, however, are directly related to the assumed annual discharge for the two branches. Long-term measurement of stream discharge and suspended-sediment concentrations would be needed to verify these loads. On the basis of the loads cal

Temporal Variability of Suspended Sediment Load, Dissolved Load, and Bedload for Two Small Oak Forested Catchments with Contrasting Disturbance Levels in the Lesser Himalaya of North-West India

NASA Astrophysics Data System (ADS)

Qazi, N. U. Q.; Rai, S. P.; Bruijnzeel, L. A.

2014-12-01

Sediment transfer from mountainous areas to lowland areas is one of the most important geomorphological processes globally with the bulk of the sediment yield from such areas typically deriving from mass wastage processes. This study presents monthly, seasonal and annual variations in sediment transport (both suspended load and bed load) as well as dissolved loads over three consecutive water years (2008-2011) for two small forested watersheds with contrasting levels of forest disturbance in the Lesser Himalaya of Northwest India. Seasonal and annual suspended sediment yields were strongly influenced by amounts of rainfall and stream flow and showed a 23-fold range between wet and dry years. Of the annual load, some 92% was produced on average during the monsoon season (June-September). Sediment production by the disturbed forest catchment was 2.6-fold (suspended sediment) to 5.9-fold (bed load) higher than that for the well-stocked forest catchment. By contrast, dissolved loads varied much less between years, seasons (although minimal during the dry summer season), and degree of forest disturbance. Total mechanical denudation rates were 1.2 times and 4.7 times larger than chemical denudation rates for the little disturbed and the heavily disturbed forest catchment, respectively whereas overall denudation rates were estimated at 0.59 and 1.05 mm per 1000 years, respectively.

Population Dynamics and Parasite Load of a Foraminifer on Its Antarctic Scallop Host with Their Carbonate Biomass Contributions.

PubMed

Hancock, Leanne G; Walker, Sally E; Pérez-Huerta, Alberto; Bowser, Samuel S

2015-01-01

We studied the population dynamics and parasite load of the foraminifer Cibicides antarcticus on its host the Antarctic scallop Adamussium colbecki from three localities differing by sea ice cover within western McMurdo Sound, Ross Sea, Antarctica: Explorers Cove, Bay of Sails and Herbertson Glacier. We also estimated CaCO3 biomass and annual production for both species. Cibicides populations varied by locality, valve type, and depth. Explorers Cove with multiannual sea ice had larger populations than the two annual sea ice localities, likely related to differences in nutrients. Populations were higher on Adamussium top valves, a surface that is elevated above the sediment. Depth did not affect Cibicides distributions except at Bay of Sails. Cibicides parasite load (the number of complete boreholes in Adamussium valves) varied by locality between 2% and 50%. For most localities the parasite load was < 20%, contrary to a previous report that ~50% of Cibicides were parasitic. The highest and lowest parasite load occurred at annual sea ice localities, suggesting that sea ice condition is not important. Rather, the number of adults that are parasitic could account for these differences. Cibicides bioerosion traces were categorized into four ontogenetic stages, ranging from newly attached recruits to parasitic adults. These traces provide an excellent proxy for population structure, revealing that Explorers Cove had a younger population than Bay of Sails. Both species are important producers of CaCO3. Cibicides CaCO3 biomass averaged 47-73 kg ha(-1) and Adamussium averaged 4987-6806 kg ha(-1) by locality. Annual production rates were much higher. Moreover, Cibicides represents 1.0-2.3% of the total host-parasite CaCO3 biomass. Despite living in the coldest waters on Earth, these species can contribute a substantial amount of CaCO3 to the Ross Sea and need to be incorporated into food webs, ecosystem models, and carbonate budgets for Antarctica.

Population Dynamics and Parasite Load of a Foraminifer on Its Antarctic Scallop Host with Their Carbonate Biomass Contributions

PubMed Central

Pérez-Huerta, Alberto; Bowser, Samuel S.

2015-01-01

We studied the population dynamics and parasite load of the foraminifer Cibicides antarcticus on its host the Antarctic scallop Adamussium colbecki from three localities differing by sea ice cover within western McMurdo Sound, Ross Sea, Antarctica: Explorers Cove, Bay of Sails and Herbertson Glacier. We also estimated CaCO3 biomass and annual production for both species. Cibicides populations varied by locality, valve type, and depth. Explorers Cove with multiannual sea ice had larger populations than the two annual sea ice localities, likely related to differences in nutrients. Populations were higher on Adamussium top valves, a surface that is elevated above the sediment. Depth did not affect Cibicides distributions except at Bay of Sails. Cibicides parasite load (the number of complete boreholes in Adamussium valves) varied by locality between 2% and 50%. For most localities the parasite load was < 20%, contrary to a previous report that ~50% of Cibicides were parasitic. The highest and lowest parasite load occurred at annual sea ice localities, suggesting that sea ice condition is not important. Rather, the number of adults that are parasitic could account for these differences. Cibicides bioerosion traces were categorized into four ontogenetic stages, ranging from newly attached recruits to parasitic adults. These traces provide an excellent proxy for population structure, revealing that Explorers Cove had a younger population than Bay of Sails. Both species are important producers of CaCO3. Cibicides CaCO3 biomass averaged 47-73 kg ha-1 and Adamussium averaged 4987-6806 kg ha-1 by locality. Annual production rates were much higher. Moreover, Cibicides represents 1.0-2.3% of the total host-parasite CaCO3 biomass. Despite living in the coldest waters on Earth, these species can contribute a substantial amount of CaCO3 to the Ross Sea and need to be incorporated into food webs, ecosystem models, and carbonate budgets for Antarctica. PMID:26186724

Herbicide concentrations in and loads transported by the Conestoga River and Pequea Creek, Lancaster County, Pennsylvania, 1992-95

USGS Publications Warehouse

Reed, Lloyd A.; Koerkle, Edward H.; Takita, Charles S.

1997-01-01

Water samples were collected from four streams in Lancaster County from 1992 through 1995 and analyzed for selected herbicides. Samples were collected from the Little Conestoga Creek near Churchtown, Mill Creek (a tributary to the Conestoga River) at Elshelman Mill Road near Lyndon, the Conestoga River at Conestoga, and Pequea Creek at Martic Forge. Most samples were collected from stormflow that occurred during the growing season. Samples were analyzed for alachlor, aldrin, atrazine, chlordane, cyanazine, dieldrin, malathion, metolachlor, propazine, simazine, and toxaphene. Most samples had detectable concentrations of alachlor, atrazine, metolachlor, and simazine, and the loads of these constituents that were transported during each of the 4 years were computed.Of the samples collected from each of the streams—Little Conestoga Creek, Mill Creek, Conestoga River, and Pequea Creek—10, 12, 15, and 18 percent, respectively, had atrazine concentrations greater than 3.0 micrograms per liter, the U.S. Environmental Protection Agency maximum contaminant level. Loads of atrazine, metolochlor, and simazine were greater than loads of any other herbicides. The largest loads were transported during 1994. Loads of atrazine transported by the four streams during periods of storm- flow from May to September 1994 totaled 3.46, 28.3, 263, and 46.8 pounds, respectively. The total loads of atrazine transported by the four streams?Little Conestoga Creek, Mill Creek, Conestoga River, and Pequea Creek—during calendar year 1994 were 6.48, 54.1, 498, and 102 pounds, respectively. A little less than half the atrazine load transported by each stream—45, 39, 42, and 42 percent, respectively—was transported during storms that occurred from May through September.Average annual yields of atrazine for the period 1992-95 were 0.59, 0.64, 0.68, and 0.51 pounds per square mile from the Little Conestoga Creek, Mill Creek, Conestoga River, and Pequea Creek, respectively. Average annual yields of simazine were 0.36, 1.2, 0.54, and 0.48 pounds per square mile, respectively, and average annual yields of metolachlor were 0.46, 0.49, 0.54, and 0.31 pounds per square mile, respectively. Less than 1 percent of both the atrazine and metolachlor that was applied to all basins was transported by streamflow.

Potential contributions of mature prairie and turfgrass to phosphorus in urban runoff.

PubMed

Steinke, K; Kussow, W R; Stier, J C

2013-07-01

Urban vegetative plantings are considered desirable to mitigate and filter stormwater runoff and nonpoint-source pollution. Phosphorus fertilization of turfgrass may enhance P in urban runoff; however, the amount of P from nonfertilized, native vegetation that could potentially replace some turf is not known. This study was conducted to measure the relative contributions of nonfertilized, native prairie vegetation and fertilized turfgrass to runoff water and P loads. Six replicates of side-by-side mature urban prairie and turfgrass were monitored for mean annual runoff volumes and P loads, biomass production, vegetative nutrient composition, and changes in soil moisture. Vegetation type did not significantly affect seasonal or annual runoff volumes or P loads. The mean annual total P loads of 0.46 kg ha for prairie and 0.28 kg ha for turfgrass were significant and comparable to those reported by other researchers when studied separately. Total P concentrations in runoff water from prairie and turf vegetation were above USEPA limits, averaging 1.86 and 1.63 mg L, respectively, over 2 yr. Averaged across 2 yr, 78% of runoff P was collected when the soil was frozen. Biomass P reductions over the period of November to April were strongly related to quantities of runoff total P from frozen soil ( = 0.874). Phosphorus losses from urban areas appeared to be primarily correlated with runoff depth, not vegetation type, because correlation coefficients revealed 86 and 45% of the Year 1 and Year 2 total P loads were directly accounted for by runoff volumes. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Analysis of non-point and point source pollution in China: case study in Shima Watershed in Guangdong Province

NASA Astrophysics Data System (ADS)

Fang, Huaiyang; Lu, Qingshui; Gao, Zhiqiang; Shi, Runhe; Gao, Wei

2013-09-01

China economy has been rapidly increased since 1978. Rapid economic growth led to fast growth of fertilizer and pesticide consumption. A significant portion of fertilizers and pesticides entered the water and caused water quality degradation. At the same time, rapid economic growth also caused more and more point source pollution discharge into the water. Eutrophication has become a major threat to the water bodies. Worsening environment problems forced governments to take measures to control water pollution. We extracted land cover from Landsat TM images; calculated point source pollution with export coefficient method; then SWAT model was run to simulate non-point source pollution. We found that the annual TP loads from industry pollution into rivers are 115.0 t in the entire watershed. Average annual TP loads from each sub-basin ranged from 0 to 189.4 ton. Higher TP loads of each basin from livestock and human living mainly occurs in the areas where they are far from large towns or cities and the TP loads from industry are relatively low. Mean annual TP loads that delivered to the streams was 246.4 tons and the highest TP loads occurred in north part of this area, and the lowest TP loads is mainly distributed in middle part. Therefore, point source pollution has much high proportion in this area and governments should take measures to control point source pollution.

The contribution of ice cover to sediment resuspension in a shallow temperate lake: possible effects of climate change on internal nutrient loading.

PubMed

Niemistö, Juha P; Horppila, Jukka

2007-01-01

The effect of ice cover on sediment resuspension and internal total P (Tot-P) loading was studied in the northern temperate Kirkkojärvi basin in Finland. The gross sedimentation and resuspension rates were estimated with sediment traps during ice-cover and ice-free periods. After ice break, the average gross sedimentation rate increased from 1.4 to 30.0 g dw m(-2) d(-1). Resuspension calculations showed clearly higher values after ice break as well. Under ice cover, resuspension ranged from 50 to 78% of the gross sedimentation while during the ice-free period it constituted from 87 to 97% of the gross sedimentation. Consequently, the average resuspension rate increased from 1.0 g dw m(-2) d(-1) under ice-cover to 27.0 g dw m(-2) d(-1) after thaw, indicating the strong effect of ice cover on sediment resuspension. To estimate the potential effect of climate change on internal P loading caused by resuspension we compared the Tot-P loading calculations between the present climate and the climate with doubled atmospheric CO2 concentration relative to the present day values (ice cover reduced from current 165 to 105 d). The annual load increased from 7.4 to 9.4 g m(-2). In conclusion, the annual internal Tot-P loading caused by resuspension will increase by 28% in the Kirkkojärvi basin if the 2xCO2 climate scenario comes true.

Phosphorus and water budgets in an agricultural basin.

PubMed

Faridmarandi, Sayena; Naja, Ghinwa M

2014-01-01

Water and phosphorus (P) budgets of a large agricultural basin located in South Florida (Everglades Agricultural Area, EAA) were computed from 2005 to 2012. The annual surface outflow P loading from the EAA averaged 157.2 mtons originating from Lake Okeechobee (16.4 mtons, 10.4%), farms (131.0 mtons, 83.4%), and surrounding basins (9.8 mtons, 6.2%) after attenuation. Farms, urban areas, and the adjacent C-139 basin contributed 186.1, 15.6, and 3.8 mtons/yr P to the canals, respectively. The average annual soil P retention was estimated at 412.5 mtons. Water and P budgets showed seasonal variations with high correlation between rainfall and P load in drainage and surface outflows. Moreover, results indicated that the canals acted as a P sink storing 64.8 mtons/yr. To assess the P loading impact of farm drainage on the canals and on the outflow, dimensionless impact factors were developed. Sixty-two farms were identified with a high and a medium impact factor I1 level contributing 44.5% of the total drainage P load to the canals, while their collective area represented less than 23% of the EAA area (172 farms). Optimizing the best management practice (BMP) strategies on these farms could minimize the environmental impacts on the downstream sensitive wetlands areas.

Improved characterization of truck traffic volumes and axle loads for mechanistic-empirical pavement design.

DOT National Transportation Integrated Search

2012-12-01

The recently developed mechanistic-empirical pavement design guide (MEPDG) requires a multitude of traffic : inputs to be defined for the design of pavement structures, including the initial two-way annual average daily truck : traffic (AADTT), direc...

THE EFFECTS OF NITROGEN LOADING AND FRESHWATER RESIDENCE TIME ON THE ESTUARINE ECOSYSTEM

EPA Science Inventory

A simple mechanistic model, designed to predict annual average concentrations of total nitrogen (TN) concentrations from nitrogen inputs and freshwater residence time in estuaries, was applied to data for several North American estuaries from previously published literature. The ...

Sources of phosphorus to the Carson River upstream from Lahontan Reservoir, Nevada and California, Water Years 2001-02

USGS Publications Warehouse

Alvarez, Nancy L.; Seiler, Ralph L.

2004-01-01

Discharge of treated municipal-sewage effluent to the Carson River in western Nevada and eastern California ceased by 1987 and resulted in a substantial decrease in phosphorus concentrations in the Carson River. Nonetheless, concentrations of total phosphorus and suspended sediment still commonly exceed beneficial-use criteria established for the Carson River by the Nevada Division of Environmental Protection. Potential sources of phosphorus in the study area include natural inputs from undisturbed soils, erosion of soils and streambanks, construction of low-head dams and their destruction during floods, manure production and grazing by cattle along streambanks, drainage from fields irrigated with streamwater and treated municipal-sewage effluent, ground-water seepage, and urban runoff including inputs from golf courses. In 2000, the U.S. Geological Survey (USGS), in cooperation with Carson Water Subconservancy District, began an investigation with the overall purpose of providing managers and regulators with information necessary to develop and implement total maximum daily loads for the Carson River. Two specific goals of the investigation were (1) to identify those reaches of the Carson River upstream from Lahontan Reservoir where the greatest increases in phosphorus and suspended-sediment concentrations and loading occur, and (2) to identify the most important sources of phosphorus within the reaches of the Carson River where the greatest increases in concentration and loading occur. Total-phosphorus concentrations in surface-water samples collected by USGS in the study area during water years 2001-02 ranged from <0.01 to 1.78 mg/L and dissolved-orthophosphate concentrations ranged from <0.01 to 1.81 mg/L as phosphorus. In streamflow entering Carson Valley from headwater areas in the East Fork Carson River, the majority of samples exceeding the total phosphorus water-quality standard of 0.1 mg/L occur during spring runoff (March, April, and May) when suspended-sediment concentrations are high. Downstream from Carson Valley, almost all samples exceed the water-quality standard, with the greatest concentrations observed during spring and summer months. Estimated annual total-phosphorus loads ranged from 1.33 tons at the West Fork Carson River at Woodfords to 43.41 tons at the Carson River near Carson City during water years 2001-02. Loads are greatest during spring runoff, followed by fall and winter, and least during the summer, which corresponds to the amount of streamflow in the Carson River. The estimated average annual phosphorus load entering Carson Valley was 21.9 tons; whereas, the estimated average annual phosphorus load leaving Carson Valley was 37.8 tons, for an annual gain in load across Carson Valley of 15.9 tons. Thus, about 58 percent of the total-phosphorus load leaving Carson Valley on an annual basis could be attributed to headwater reaches upstream from Carson Valley. During spring and summer (April 1-September 30) an average of 85 percent of the total-phosphorus load leaving Carson Valley could be attributed to headwater reaches. During fall and winter (October 1-March 31) only 17 percent of the phosphorus load leaving Carson Valley could be attributed to headwater reaches. The composition of the phosphorus changes during summer from particulate phosphorus entering Carson Valley to dissolved orthophosphate leaving Carson Valley. Particulate phosphorus entering Carson Valley could be settling out when water is applied to fields and be replaced by dissolved orthophosphate from other sources. Alternatively, the particulate phosphorus could be converted to dissolved orthophosphate as it travels across Carson Valley. Data collected during the study are not sufficient to distinguish between the two possibilities. Eagle Valley and Dayton-Churchill Valleys may act as sinks for phosphorus. On an annual basis, during water years 2001-02, about 90 percent of the phosphorus entering Eagle Valley left the

Continuous 'Passive' Registration of Non-Point Contaminant Loads Via Agricultural Subsurface Drain Tubes

NASA Astrophysics Data System (ADS)

Rozemeijer, J.; Jansen, S.; de Jonge, H.; Lindblad Vendelboe, A.

2014-12-01

Considering their crucial role in water and solute transport, enhanced monitoring and modeling of agricultural subsurface tube drain systems is important for adequate water quality management. For example, previous work in lowland agricultural catchments has shown that subsurface tube drain effluent contributed up to 80% of the annual discharge and 90-92% of the annual NO3 loads from agricultural fields towards the surface water. However, existing monitoring techniques for flow and contaminant loads from tube drains are expensive and labor-intensive. Therefore, despite the unambiguous relevance of this transport route, tube drain monitoring data are scarce. The presented study aimed developing a cheap, simple, and robust method to monitor loads from tube drains. We are now ready to introduce the Flowcap that can be attached to the outlet of tube drains and is capable of registering total flow, contaminant loads, and flow-averaged concentrations. The Flowcap builds on the existing SorbiCells, a modern passive sampling technique that measures average concentrations over longer periods of time (days to months) for various substances. By mounting SorbiCells in our Flowcap, a flow-proportional part of the drain effluent is sampled from the main stream. Laboratory testing yielded good linear relations (R-squared of 0.98) between drainage flow rates and sampling rates. The Flowcap was tested in practice for measuring NO3 loads from two agricultural fields and one glasshouse in the Netherlands. The Flowcap registers contaminant loads from tube drains without any need for housing, electricity, or maintenance. This enables large-scale monitoring of non-point contaminant loads via tube drains, which would facilitate the improvement of contaminant transport models and would yield valuable information for the selection and evaluation of mitigation options to improve water quality.

Annual variability of PAH concentrations in the Potomac River watershed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maher, I.L.; Foster, G.D.

1995-12-31

Dynamics of organic contaminant transport in a large river system is influenced by annual variability in organic contaminant concentrations. Surface runoff and groundwater input control the flow of river waters. They are also the two major inputs of contaminants to river waters. The annual variability of contaminant concentrations in rivers may or may not represent similar trends to the flow changes of river waters. The purpose of the research is to define the annual variability in concentrations of polycyclic aromatic hydrocarbons (PAH) in riverine environment. To accomplish this, from March 1992 to March 1995 samples of Potomac River water weremore » collected monthly or bimonthly downstream of the Chesapeake Bay fall line (Chain Bridge) during base flow and main storm flow hydrologic conditions. Concentrations of selected PAHs were measured in the dissolved phase and the particulate phase via GC/MS. The study of the annual variability of PAH concentrations will be performed through comparisons of PAH concentrations seasonally, annually, and through study of PAH concentration river discharge dependency and rainfall dependency. For selected PAHs monthly and annual loadings will be estimated based on their measured concentrations and average daily river discharge. The monthly loadings of selected PAHs will be compared by seasons and annually.« less

Dramatic decreases in runoff and sediment load in the Huangfuchuan Basin of the Middle Yellow River, China: historical records and future projections

NASA Astrophysics Data System (ADS)

LI, E.; Li, D.; Wang, Y.; Fu, X.

2017-12-01

The Yellow River is well known for its high sediment load and serious water shortage. The long-term averaged sediment load is about 1.6´103 million tons per year, resulting in aggrading and perched lower reaches. In recent years, however, dramatic decreases in runoff and sediment load have been observed. The annual sediment load has been less than 150 million tons in the last ten years. Extrapolation of this trend into the future would motivate substantial change in the management strategies of the Lower Yellow River. To understand the possible trend and its coevolving drivers, we performed a case study of the Huangfuchuang River, which is a tributary to the Middle Yellow River, with a drainage area of 3246 km2 and an annual precipitation of 365 mm. Statistical analysis of historical data from 1960s to 2015 showed a significantly decreasing trend in runoff and sediment load since 1984. As potential drivers, the precipitation does not show an obvious change in annual amount, while the vegetation cover and the number of check dams have been increased gradually as a result of the national Grain for Green project. A simulation with the Soil and Water Assessment Tool (SWAT) reproduced the historical evolution processes, and showed that human activities dominated the reduction in runoff and sediment load, with a contribution of around 80%. We then projected the runoff and sediment load for the next 50 years (2016-2066), considering typical scenarios of climate change and accounting for vegetation cover development subject to climate conditions and storage capacity loss of check dams due to sediment deposition. The differences between the projected trend and the historical record were analyzed, so as to highlight the coevolving processes of climate, vegetation, and check dam retention on a time scale of decades. Keywords: Huangfuchuan River Basin, sediment load, vegetation cover, check dams, annual precipitation, SWAT.

Monitoring and Characterization of Miscellaneous Electrical Loads in a Large Retail Environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gentile-Polese, L.; Frank, S.; Sheppy, M.

2014-02-01

Buildings account for 40% of primary energy consumption in the United States (residential 22%; commercial 18%). Most (70% residential and 79% commercial) is used as electricity. Thus, almost 30% of U.S. primary energy is used to provide electricity to buildings. Plug loads play an increasingly critical role in reducing energy use in new buildings (because of their increased efficiency requirements), and in existing buildings (as a significant energy savings opportunity). If all installed commercial building miscellaneous electrical loads (CMELs) were replaced with energy-efficient equipment, a potential annual energy saving of 175 TWh, or 35% of the 504 TWh annual energymore » use devoted to MELs, could be achieved. This energy saving is equivalent to the annual energy production of 14 average-sized nuclear power plants. To meet DOE's long-term goals of reducing commercial building energy use and carbon emissions, the energy efficiency community must better understand the components and drivers of CMEL energy use, and develop effective reduction strategies. These goals can be facilitated through improved data collection and monitoring methodologies, and evaluation of CMELs energy-saving techniques.« less

Bed material transport in the Virgin River, Utah

USGS Publications Warehouse

Andrews, E.D.

2000-01-01

Detailed information concerning the rate and particle size distribution of bed material transport by streamflows can be very difficult and expensive to obtain, especially where peak streamflows are brief and bed material is poorly sorted, including some very large boulders. Such streams, however, are common in steep, arid watersheds. Any computational approach must consider that (1) only the smaller particle sizes present on the streambed move even during large floods and (2) the largest bed particles exert a significant form drag on the flow. Conventional methods that rely on a single particle size to estimate the skin friction shear stress acting on the mobile fraction of the bed material perform poorly. Instead, for this study, the skin friction shear stress was calculated for the observed range of streamflows by calculating the form drag exerted on the reach‐averaged flow field by all particle sizes. Suspended and bed load transported rates computed from reach‐averaged skin friction shear stress are in excellent agreement with measured transport rates. The computed mean annual bed material load, including both bed load and suspended load, of the East Fork Virgin River for the water years 1992‐1996 was approximately 1.3×10 5 t. A large portion of the bed material load consists of sand‐sized particles, 0.062–1.0 mm in diameter, that are transported in suspension. Such particles, however, constituted only 10% of the surface bed material and less than 25% of the subsurface bed material. The mean annual quantity of bed load transported was 1060 t/yr with a median size of 15 mm.

Nitrate trends in the Adirondack Mountains, Northeastern US, 1993-2007

EPA Science Inventory

The Adirondack Mountains in New York State receive some of the highest rates of nitrogen deposition in the Northeastern U.S. Between 1993 and 2007, nitrogen deposition loads did not significantly change and average annual wet inorganic nitrogen deposition was 6 kg/ha (Figure 1)....

Bayesian network for point and diffuse source phosphorus transfer from dairy pastures in South otago, new zealand.

PubMed

Lucci, Gina M; Nash, David; McDowell, Richard W; Condron, Leo M

2014-07-01

Many factors affect the magnitude of nutrient losses from dairy farm systems. Bayesian Networks (BNs) are an alternative to conventional modeling that can evaluate complex multifactor problems using forward and backward reasoning. A BN of annual total phosphorus (TP) exports was developed for a hypothetical dairy farm in the south Otago region of New Zealand and was used to investigate and integrate the effects of different management options under contrasting rainfall and drainage regimes. Published literature was consulted to quantify the relationships that underpin the BN, with preference given to data and relationships derived from the Otago region. In its default state, the BN estimated loads of 0.34 ± 0.42 kg TP ha for overland flow and 0.30 ± 0.19 kg TP ha for subsurface flow, which are in line with reported TP losses in overland flow (0-1.1 kg TP ha) and in drainage (0.15-2.2 kg TP ha). Site attributes that cannot be managed, like annual rainfall and the average slope of the farm, were found to affect the loads of TP lost from dairy farms. The greatest loads (13.4 kg TP ha) were predicted to occur with above-average annual rainfall (970 mm), where irrigation of farm dairy effluent was managed poorly, and where Olsen P concentrations were above pasture requirements (60 mg kg). Most of this loading was attributed to contributions from overland flow. This study demonstrates the value of using a BN to understand the complex interactions between site variables affecting P loss and their relative importance. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Rye cover crop and gamagrass strip effects on NO3 concentration and load in tile drainage.

PubMed

Kaspar, T C; Jaynes, D B; Parkin, T B; Moorman, T B

2007-01-01

A significant portion of the NO3 from agricultural fields that contaminates surface waters in the Midwest Corn Belt is transported to streams or rivers by subsurface drainage systems or "tiles." Previous research has shown that N fertilizer management alone is not sufficient for reducing NO3 concentrations in subsurface drainage to acceptable levels; therefore, additional approaches need to be devised. We compared two cropping system modifications for NO3 concentration and load in subsurface drainage water for a no-till corn (Zea mays L.)-soybean (Glycine max [L.] Merr.) management system. In one treatment, eastern gamagrass (Tripsacum dactyloides L.) was grown in permanent 3.05-m-wide strips above the tiles. For the second treatment, a rye (Secale cereale L.) winter cover crop was seeded over the entire plot area each year near harvest and chemically killed before planting the following spring. Twelve 30.5x42.7-m subsurface-drained field plots were established in 1999 with an automated system for measuring tile flow and collecting flow-weighted samples. Both treatments and a control were initiated in 2000 and replicated four times. Full establishment of both treatments did not occur until fall 2001 because of dry conditions. Treatment comparisons were conducted from 2002 through 2005. The rye cover crop treatment significantly reduced subsurface drainage water flow-weighted NO3 concentrations and NO3 loads in all 4 yr. The rye cover crop treatment did not significantly reduce cumulative annual drainage. Averaged over 4 yr, the rye cover crop reduced flow-weighted NO3 concentrations by 59% and loads by 61%. The gamagrass strips did not significantly reduce cumulative drainage, the average annual flow-weighted NO3 concentrations, or cumulative NO3 loads averaged over the 4 yr. Rye winter cover crops grown after corn and soybean have the potential to reduce the NO3 concentrations and loads delivered to surface waters by subsurface drainage systems.

Sediment transport and water-quality characteristics and loads, White River, northwestern Colorado, water years 1975-88

USGS Publications Warehouse

Tobin, R.L.

1993-01-01

Streamflow, sediment, and water-quality data are summarized for 6 sites on the White River, Colorado for water years 1975-88. Correlation techniques were used to estimate annual data for unmeasured years. Annual stream discharge in the main stem of the White River ranged from about 200,000 to about 1 million acre-feet. Generally, bedload was less than/= 3.3 percent of total sediment load. Annual suspended-sediment loads ranged from about 2,100 tons at the upstream sites on the North Fork and South Fork of the White River to about 2 million tons at the most downstream site. Average annual suspended-sediment loads ranged from about 11,000 tons at the upstream sites to about 705,000 tons at the most downstream site. Annual capacity losses in a 50,000 acre-ft reservoir could range from less than 0.01 percent near upstream sites to about 2.5 percent near downstream sites. Maximum water temperatures in the White River ranged from less than 20 to 25 C in summer. Specific conductance ranged from 200 to 1,000 microsiemens/cm. Generally, values of pH ranged from 7.6 to 8.8, and concentrations of dissolved oxygen were greater than 6.0 mg/L. In small streamflows, values of pH and dissolved oxygen were affected by biologic processes. Composition of dissolved solids in the White River was mostly calcium, bicarbonate, and(or) sulfate. Changes in the composition of dissolved solids caused by the changes in the concentrations of sodium and sulfate were greatest in small stream discharges. Annual loads of dissolved solids ranged from 21,100 tons in the South Fork to about 480,000 tons at the most downstream site. Total solids transport in the White River was mostly as dissolved solids at upstream sites and mostly as suspended sediment at downstream sites. Concentration ranges of nutrients and trace constituents were determined.

40 CFR 60.1885 - What must I include in my annual report?

Code of Federal Regulations, 2011 CFR

2011-07-01

... monitoring system (§ 60.1850(a)(1)). (d) For municipal waste combustion units that use activated carbon for controlling dioxins/furans or mercury emissions, include four records: (1) The average carbon feed rates... municipal waste combustion units only, nitrogen oxides emissions. (3) Carbon monoxide emissions. (4) Load...

40 CFR 60.1410 - What must I include in my annual report?

Code of Federal Regulations, 2011 CFR

2011-07-01

...) For municipal waste combustion units that use activated carbon for controlling dioxins/furans or mercury emissions, include four records: (1) The average carbon feed rates recorded during the most recent..., nitrogen oxides emissions. (3) Carbon monoxide emissions. (4) Load level of the municipal waste combustion...

Sediment transport, particle sizes, and loads in lower reaches of the Chippewa, Black and Wisconsin Rivers in Western Wisconsin

USGS Publications Warehouse

Rose, W.J.

1992-01-01

Average annual total-sediment load and the percentage transported as bedload were determined for a 10-year period (water years 1974-83)(October 1,1973-September 30, 1982). These loads and percentages were, respectively, 123,000 tons and 35 percent at Chippewa River near Caryville; 1,073,000 tons and 61 percent at Chippewa River at Durand; 940,000 tons and 44 percent at Chippewa River near Pepin; 277,000 tons and 43 percent at Black River near Galesville; and 558,000 tons and 49 percent at Wisconsin River at Muscoda.

Generalized sediment budgets of the Lower Missouri River, 1968–2014

USGS Publications Warehouse

Heimann, David C.

2016-09-13

Sediment budgets of the Lower Missouri River were developed in a study led by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers. The scope of the study included the development of a long-term (post-impoundment, 1968–2014) average annual sediment budget and selected annual, monthly, and daily sediment budgets for a reach and period that adequate data were available. Included in the analyses were 31 main-stem and tributary stations of the Lower Missouri River and two Mississippi River stations—the Mississippi River below Grafton, Illinois, and the Mississippi River at St. Louis, Missouri.Long-term average annual suspended-sediment loads of Missouri River main-stem stations ranged from 0.33 million tons at the Missouri River at Yankton, South Dakota, station to 71.2 million tons at Missouri River at Hermann, Mo., station. Gaged tributary gains accounted for 9–36 percent of the local reach budgets and cumulative gaged tributary contributions accounted for 84 percent of the long-term average suspended-sediment load of the Missouri River at Hermann, Mo., station. Although the sediment budgets for seven defined main-stem reaches generally were incomplete—missing bedload, reach storage, and ungaged tributary contributions—the budget residuals (net result of sediment inputs and outputs) for six of the seven reaches ranged from -7.0 to 1.7 million tons, or from -9.2 to 4.0 percent of the reach output suspended-sediment load, and were within the 10 percent reported measurement error of annual suspended-sediment loads for large rivers. The remaining reach, downstream from Gavin’s Point Dam, extended from Yankton, S. Dak., to Sioux City, Iowa, and had a budget residual of -9.8 million tons, which was -88 percent of the suspended-sediment load at Sioux City.The Lower Missouri River reach from Omaha, Nebraska, to Nebraska City, Nebr., had periods of concurrent sediment data for each primary budget component with which to analyze and determine a suspended-sediment budget for selected annual, monthly, and daily time increments. The temporal changes in the cumulative annual budget residuals were poorly correlated with the comparatively steady 1968–2011 annual stage trends at the Missouri River at Nebraska City, Nebr., station. An accurate total sediment budget is developed by having concurrent data available for all primary suspended and bedload components for a reach of interest throughout a period. Such a complete budget, with concurrent record for suspended-sediment load and bedload components, is unavailable for any reach and period in the Lower Missouri River. The primary data gaps are in bedload data, and also in suspended-sediment gains and losses including ungaged tributary inputs and sediment storage. Bedload data gaps in the Missouri River Basin are much more prevalent than suspended-sediment data gaps, and the first step in the development of reach bedload budgets is the establishment of a standardized bedload monitoring program at main-stem stations.The temporal changes in flow-adjusted suspended-sediment concentrations analyzed at main-stem Missouri River stations indicated an overall downward change in concentrations between 1968 and 2014. Temporary declines in flow-adjusted suspended-sediment concentrations during and following large floods were evident but generally returned to near pre-flood values within about 6 months.Data uncertainties associated with the development of a sediment budget include uncertainties associated with the collection of suspended-sediment and bedload data and the computation of suspended-sediment loads. These uncertainties vary depending on the frequency of data collection, the variability of conditions being represented by the discrete samples, and the statistical approach to suspended-sediment load computations. The coefficients of variation of suspended-sediment loads of Missouri River tributary stations for 1968–2014 were greater, 75.0 percent, than the main-stem stations, 47.1 percent. The lower coefficient of variation at main-stem stations compared to tributaries, primarily is the result of the lower variability in streamflow and sediment discharge identified at main-stem stations. To obtain similar accuracy between suspended-sediment loads at main-stem and tributary stations, a longer period of record is required of the tributary stations. During 1968–2014, however, the Missouri River main-stem station record was much more complete (87 percent) than the tributary station record (28 percent).

Fluvial sediment in the little Arkansas River basin, Kansas

USGS Publications Warehouse

Albert, C.D.; Stramel, G.J.

1966-01-01

Characteristics and transport of sediment in the Little Arkansas River basin in south-central Kansas were studied to determine if the water from the river could be used as a supplemental source for municipal supply or would provide adequate recharge to aquifers that are sources of municipal and agricultural water supplies. During periods when overland 1low contributed a significant amount to streamflow, the suspended sediment in the Little Arkansas River at Valley Center averaged about 85 percent of clay, about 13 percent of silt, and about 2 percent of sand. The average annual suspended-sediment discharge for the water years 1958, 1959, 1960, and 1961 was about 306,000 tons, and about 80 percent of the load was transported during 133 days of the 1,461-day period. The average daily water discharge of 352 cubic feet per second for the period 1958-61 was more than the long-term (i}9-year) average of 245 cfs; therefore, the average annual sediment load for 1958-61 was probably greater than the average annual load for the same long-term period. Studies of seepage in a part of the channel of Kisiwa Creek indicated that an upstream gravel-pit operation yielded clays which, when deposited in the channel, reduced seepage. A change in plant operation and subsequent runoff that removed the deposited clays restored natural seepage conditions. Experiments by the Wichita Water Department showed that artificial recharge probably cannot be accomplished by using raw turbid water that is injected into wells or by using pits. Recharge by raw turbid water on large permeable areas or by seepage canals may be feasible. Studies of chemical quality of surface water at several sites in the Little Arkansas River basin indicate that Turkey. Creek is a major contributor of chloride and other dissolved solids to the Little Arkansas River and that the dissolved-solids content is probably highest during low-flow periods when suspended-sediment concentration is low. Data collected by the Wichita Water Department indicate that chloride concentrations are diminishing with time at sampled locations. and they receive recharge from rainwater and snowmelt moving through overlying alluvium and from storage in the De Chelly sandstone which encloses the east half of the diatreme. The quality of water from all areas is suitable for domestic use. However, special treatment may be necessary to make the water suitable for pulp processing.

Suspended-sediment data in the Salt River basin, Missouri

USGS Publications Warehouse

Berkas, Wayne R.

1983-01-01

Suspended-sediment data collected at six stations in the Salt River basin during 1980-82 are presented. The estimated average annual suspended-sediment load is 1,390,000 tons per year from a geomorphic examination, and 1,330,000 tons per year from periodic sampling at Salt River near Monroe City, Mo. The suspended-sediment load from the major tributaries of the Salt River during 1981 was 1,610,000 tons, which is larger than the estimated values due to above-normal rainfall and runoff. (USGS)

Internal loading of phosphorus in western Lake Erie

USGS Publications Warehouse

Matisoff, Gerald; Kaltenberg, Eliza M.; Steely, Rebecca L.; Hummel, Stephanie K.; Seo, Jinyu; Gibbons, Kenneth J.; Bridgeman, Thomas B.; Seo, Youngwoo; Behbahani, Mohsen; James, William F.; Johnson, Laura; Doan, Phuong; Dittrich, Maria; Evans, Mary Anne; Chaffin, Justin D.

2016-01-01

This study applied eight techniques to obtain estimates of the diffusive flux of phosphorus (P) from bottom sediments throughout the western basin of Lake Erie. The flux was quantified from both aerobic and anaerobic incubations of whole cores; by monitoring the water encapsulated in bottom chambers; from pore water concentration profiles measured with a phosphate microelectrode, a diffusive equilibrium in thin films (DET) hydrogel, and expressed pore waters; and from mass balance and biogeochemical diagenetic models. Fluxes under aerobic conditions at summertime temperatures averaged 1.35 mg P/m2/day and displayed spatial variability on scales as small as a centimeter. Using two different temperature correction factors, the flux was adjusted to mean annual temperature yielding average annual fluxes of 0.43–0.91 mg P/m2/day and a western basin-wide total of 378–808 Mg P/year as the diffusive flux from sediments. This is 3–7% of the 11,000 Mg P/year International Joint Commission (IJC) target load for phosphorus delivery to Lake Erie from external sources. Using these average aerobic fluxes, the sediment contributes 3.0–6.3 μg P/L as a background internal contribution that represents 20–42% of the IJC Target Concentration of 15 μg P/L for the western basin. The implication is that this internal diffusive recycling of P is unlikely to trigger cyanobacterial blooms by itself but is sufficiently large to cause blooms when combined with external loads. This background flux may be also responsible for delayed response of the lake to any decrease in the external loading.

Crustal displacements due to continental water loading

USGS Publications Warehouse

Van Dam, T.; Wahr, J.; Milly, P.C.D.; Shmakin, A.B.; Blewitt, G.; Lavallee, D.; Larson, K.M.

2001-01-01

The effects of long-wavelength (> 100 km), seasonal variability in continental water storage on vertical crustal motions are assessed. The modeled vertical displacements (??rM) have root-mean-square (RMS) values for 1994-1998 as large as 8 mm, with ranges up to 30 mm, and are predominantly annual in character. Regional strains are on the order of 20 nanostrain for tilt and 5 nanostrain for horizontal deformation. We compare ??rM with observed Global Positioning System (GPS) heights (??rO) (which include adjustments to remove estimated effects of atmospheric pressure and annual tidal and non-tidal ocean loading) for 147 globally distributed sites. When the ??rO time series are adjusted by ??rM, their variances are reduced, on average, by an amount equal to the variance of the ??rM. Of the ??rO time series exhibiting a strong annual signal, more than half are found to have an annual harmonic that is in phase and of comparable amplitude with the annual harmonic in the ??rM. The ??rM time series exhibit long-period variations that could be mistaken for secular tectonic trends or post-glacial rebound when observed over a time span of a few years.

Organic micropollutants in the Yangtze River: seasonal occurrence and annual loads.

PubMed

Qi, Weixiao; Müller, Beat; Pernet-Coudrier, Benoit; Singer, Heinz; Liu, Huijuan; Qu, Jiuhui; Berg, Michael

2014-02-15

Twenty percent of the water run-off from China's land surface drains into the Yangtze River and carries the sewage of approximately 400 million people out to sea. The lower stretch of the Yangtze therefore offers the opportunity to assess the pollutant discharge of a huge population. To establish a comprehensive assessment of micropollutants, river water samples were collected monthly from May 2009 to June 2010 along a cross-section at the lowermost hydrological station of the Yangtze River not influenced by the tide (Datong Station, Anhui province). Following a prescreening of 268 target compounds, we examined the occurrence, seasonal variation, and annual loads of 117 organic micropollutants, including 51 pesticides, 43 pharmaceuticals, 7 household and industrial chemicals, and 16 polycyclic aromatic hydrocarbons (PAHs). During the 14-month study, the maximum concentrations of particulate PAHs (1-5 μg/g), pesticides (11-284 ng/L), pharmaceuticals (5-224 ng/L), and household and industrial chemicals (4-430 ng/L) were generally lower than in other Chinese rivers due to the dilution caused of the Yangtze River's average water discharge of approximately 30,000 m(3)/s. The loads of most pesticides, anti-infectives, and PAHs were higher in the wet season compared to the dry season, which was attributed to the increased agricultural application of chemicals in the summer, an elevated water discharge through the sewer systems and wastewater treatment plants (WWTP) as a result of high hydraulic loads and the related lower treatment efficiency, and seasonally increased deposition from the atmosphere and runoff from the catchment. The estimated annual load of PAHs in the river accounted for some 4% of the total emission of PAHs in the whole Yangtze Basin. Furthermore, by using sucralose as a tracer for domestic wastewater, we estimate a daily disposal of approximately 47 million m(3) of sewage into the river, corresponding to 1.8% of its average hydraulic load. In summary, the annual amounts flushed by the Yangtze River into the East China Sea were 2.9×10(6)tons of dissolved and particulate organic carbon (DOC and POC), 369 tons of PAHs, 98 tons of pesticides, 152 tons of pharmaceuticals, and 273 tons of household and industrial chemicals. While the concentrations seem comparably moderate, the pollutant loads are considerable and pose an increasing burden to the health of the marine coastal ecosystem. Copyright © 2013 Elsevier B.V. All rights reserved.

Sediment transport by streams in the Palouse River basin, Washington and Idaho, July 1961-June 1965

USGS Publications Warehouse

Boucher, P.R.

1970-01-01

The Palouse River basin covers about 3,300 square miles in southeastern Washington and northwestern Idaho. The eastern part of the basin is composed of steptoes and foothills which are generally above an altitude of 2,600 feet; the central part is of moderate local relief and is mantled chiefly by thick loess deposits; and the western part is characterized by low relief and scabland topography and is underlain mostly by basalt. Precipitation increases eastward across the study area. It ranges annually from 12 to 18 inches in the western part and from 14 to 23 inches in the central part, and it exceeds 40 inches in the eastern part. Surface runoff from the basin for the 4-year period of study (July 1961-June 1965) averaged 408,000 acre-feet per year, compared with 445,200 acre-feet per year for the 27-year period of record. The eastern part of the basin contributed about 55 percent of the total, whereas the central and western parts contributed 37 percent and 8 percent, respectively. Most sediment transport from the Palouse River basin and the highest sediment concentrations in streams occurred in the winter. Of the several storms during the study period, those of February 3-9, 1963, December 22-27, 1964, and January 27-February 4, 1965, accounted for 81 percent of the total 4-year suspended-sediment load; the storm of February 3-9, 1963, accounted for nearly one-half the total load. The discharge-weighted mean concentration of suspended sediment carried in the Palouse River past Hooper during the study period was 2,970 milligrams per liter. The average annual sediment discharge of the Palouse River at its mouth was about 1,580,000 tons per year, and the estimated average annual sediment yield was 480 tons per square mile. The yield ranged from 5 tons per square mile from the western part of the basin to 2,100 tons per square mile from the central part. The high yield from the central part is attributed to a scarcity of vegetal cover, to the fine-grained loess soils, and to rapid runoff during winter storms. Sediment yield from the eastern part of the basin ranged from 460 to more than 1,000 tons per square mile. During high flow, silt particles make up the largest part of the suspended-sediment load, whereas during low flow, clay particles represent the greatest part. On the average, the suspended sediment transported by the Palouse River past Hooper contained 3 percent sand, 68 percent silt, and 29 percent clay. Unmeasured sediment discharge was estimated to have been 5 percent of the total sediment discharge. Data collected during the 4-year period of study show that sediment loads were higher than those recorded by V. G. Kaiser during the longer period 1939-65. Whereas Kaiser's study showed an average annual soil loss of 9.6 million tons, the average annual loss during the recent study was 14.2 million tons. The factor that has had the greatest effect on the increase of sediment yields is land use. Lands once covered and protected by natural vegetation have been extensively, cultivated, and much of the soil has become susceptible to erosion, particularly in areas mantled by loessal soils.

Spatial distribution and output characteristics of nonpoint source pollution in the Dongjiang River basin in south China

NASA Astrophysics Data System (ADS)

Rong, Q. Q.; Su, M. R.; Yang, Z. F.; Cai, Y. P.; Yue, W. C.; Dang, Z.

2018-02-01

In this research, the Dongjiang River basin was taken as the study area to analyze the spatial distribution and output characteristics of nonpoint source pollution, based on the export coefficient model. The results showed that the annual total nitrogen and phosphorus (i.e. TN and TP) loads from the Dongjiang River basin were 67916114.6 and 7215279.707 kg, respectively. Residents, forestland and pig were the main contributors for the TN load in the Dongjiang River basin, while residents, forestland and rainfed croplands were the three largest contributors for the TP load. The NPS pollution had a significant spatial variation in this area. The pollution loads overall decreased from the northeast to the southwest part of the basin. Also, the pollution loads from the gentle slope area were larger than those from steep slope areas. Among the ten tributary watersheds in the Dongjiang River basin, the TN and TP loads from the Hanxi River watershed were the largest. On the contrary, the Gongzhuang River watershed contributed least to the total pollution loads of the Dongjiang River basin. For the average pollution load intensities, Hanxi River watershed was still the largest. However, the smallest average TN and TP load intensities were in the Xinfeng River watershed.

76 FR 23459 - Federal Agricultural Mortgage Corporation Governance and Federal Agricultural Mortgage...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-27

... that cumulative loss rates should, at the very least, be no greater than those for comparably sized... identifying rural utilities credit loss risk, and Farmer Mac has offered no evidence to demonstrate that our... likely long-term average annual losses on an investment, in addition to fee loads to cover operating...

Eutrophication study at the Panjiakou-Daheiting Reservoir system, northern Hebei Province, People's Republic of China: Chlorophyll-a model and sources of phosphorus and nitrogen

USGS Publications Warehouse

Domagalski, Joseph L.; Lin, Chao; Luo, Yang; Kang, Jie; Wang, Shaoming; Brown, Larry R.; Munn, Mark D.

2007-01-01

Concentrations, loads, and sources of nitrate and total phosphorus were investigated at the Panjiakou and Daheiting Reservoir system in northern Hebei Province, People's Republic of China. The Luan He River is the primary source of water to these reservoirs, and the upstream watershed has a mix of land uses including agriculture, forest, and one large urban center. The reservoirs have a primary use for storage of drinking water and partially supply Tianjin City with its annual needs. Secondary uses include flood control and aqua culture (fish cages). The response of the reservoir system from phosphorus input, with respect to chlorophyll-a production from algae, was fitted to a model of normalized phosphorus loading that regresses the average summer-time chlorophyll-a concentration to the average annual phosphorus concentration of the reservoir. Comparison of the normalized phosphorus loading and chlorophyll-a response of this system to other reservoirs throughout the world indicate a level of eutrophication that will require up to an approximate 5–10-fold decrease in annual phosphorus load to bring the system to a more acceptable level of algal productivity. Isotopes of nitrogen and oxygen in dissolved nitrate were measured from the headwater streams and at various locations along the major rivers that provide the majority of water to these reservoirs. Those isotopic measurements indicate that the sources of nitrate change from natural background in the rivers to animal manure and septic waste upstream of the reservoir. Although the isotopic measurements suggest that animal and septic wastes are a primary source of nutrients, measurements of the molar ratio of nitrogen to phosphorus are more indicative of row-cropping practices. Options for reduction of nutrient loads include changing the management practices of the aqua culture, installation of new sewage treatment systems in the large urbanized area of the upper watershed, and agricultural management practices that would reduce the loading of nutrients and soil erosion from that land use.

Estimation of streamflow, base flow, and nitrate-nitrogen loads in Iowa using multiple linear regression models

USGS Publications Warehouse

Schilling, K.E.; Wolter, C.F.

2005-01-01

Nineteen variables, including precipitation, soils and geology, land use, and basin morphologic characteristics, were evaluated to develop Iowa regression models to predict total streamflow (Q), base flow (Qb), storm flow (Qs) and base flow percentage (%Qb) in gauged and ungauged watersheds in the state. Discharge records from a set of 33 watersheds across the state for the 1980 to 2000 period were separated into Qb and Qs. Multiple linear regression found that 75.5 percent of long term average Q was explained by rainfall, sand content, and row crop percentage variables, whereas 88.5 percent of Qb was explained by these three variables plus permeability and floodplain area variables. Qs was explained by average rainfall and %Qb was a function of row crop percentage, permeability, and basin slope variables. Regional regression models developed for long term average Q and Qb were adapted to annual rainfall and showed good correlation between measured and predicted values. Combining the regression model for Q with an estimate of mean annual nitrate concentration, a map of potential nitrate loads in the state was produced. Results from this study have important implications for understanding geomorphic and land use controls on streamflow and base flow in Iowa watersheds and similar agriculture dominated watersheds in the glaciated Midwest. (JAWRA) (Copyright ?? 2005).

Study on phosphorus loadings in ten natural and agricultural watersheds in subtropical region of China.

PubMed

Li, Yuyuan; Meng, Cen; Gao, Ru; Yang, Wen; Jiao, Junxia; Li, Yong; Wang, Yi; Wu, Jinshui

2014-05-01

Water eutrophication in subtropical regions of southern China threatens watershed health and is of major concern. However, annual phosphorus (P) loading and its dominant causes are still unclear, especially at the watershed scale. In this study, we investigated dynamic P loadings and associated factors (e.g., land use, livestock production, and runoff depth) in ten watersheds that varied in area from 9 to 5,212 ha in a hilly area of Hunan Province, China. A flowmeter was installed at the outlet of each watershed, and total P (TP) and soluble P (SP) concentrations were monitored periodically from June 2010 to October 2012. The results showed that annual P loadings (APLs) in the ten watersheds ranged from 22.8 to 247.8 kg P/km(2) and that P loss primarily occurred from April to June of each year during the main rainfall season in the study area. In addition, the average eutrophication (>0.05 mg P/L) ratio for stream waters was 86.7 % during the study period, which was indicative of a potentially serious condition for the local water environments. Annual P loadings were linearly related to livestock density (LD; R = 0.92, p < 0.01), whereas the eutrophication ratio of stream water was significantly (p < 0.05) correlated with LD (R = 0.61), percentage cropland (R = 0.71), and percentage forest cover (R = -0.68). Thus, it is concluded that the control of livestock production has the greatest potential for reducing P loadings in watersheds in this subtropical area. This will be beneficial to the amelioration and protection of local environment.

Phosphorus and suspended sediment load estimates for the Lower Boise River, Idaho, 1994-2002

USGS Publications Warehouse

Donato, Mary M.; MacCoy, Dorene E.

2004-01-01

The U.S. Geological Survey used LOADEST, newly developed load estimation software, to develop regression equations and estimate loads of total phosphorus (TP), dissolved orthophosphorus (OP), and suspended sediment (SS) from January 1994 through September 2002 at four sites on the lower Boise River: Boise River below Diversion Dam near Boise, Boise River at Glenwood Bridge at Boise, Boise River near Middleton, and Boise River near Parma. The objective was to help the Idaho Department of Environmental Quality develop and implement total maximum daily loads (TMDLs) by providing spatial and temporal resolution for phosphorus and sediment loads and enabling load estimates made by mass balance calculations to be refined and validated. Regression models for TP and OP generally were well fit on the basis of regression coefficients of determination (R2), but results varied in quality from site to site. The TP and OP results for Glenwood probably were affected by the upstream wastewater-treatment plant outlet, which provides a variable phosphorus input that is unrelated to river discharge. Regression models for SS generally were statistically well fit. Regression models for Middleton for all constituents, although statistically acceptable, were of limited usefulness because sparse and intermittent discharge data at that site caused many gaps in the resulting estimates. Although the models successfully simulated measured loads under predominant flow conditions, errors in TP and SS estimates at Middleton and in TP estimates at Parma were larger during high- and low-flow conditions. This shortcoming might be improved if additional concentration data for a wider range of flow conditions were available for calibrating the model. The average estimated daily TP load ranged from less than 250 pounds per day (lb/d) at Diversion to nearly 2,200 lb/d at Parma. Estimated TP loads at all four sites displayed cyclical variations coinciding with seasonal fluctuations in discharge. Estimated annual loads of TP ranged from less than 8 tons at Diversion to 570 tons at Parma. Annual loads of dissolved OP peaked in 1997 at all sites and were consistently higher at Parma than at the other sites. The ratio of OP to TP varied considerably throughout the year at all sites. Peaks in the OP:TP ratio occurred primarily when flows were at their lowest annual stages; estimated seasonal OP:TP ratios were highest in autumn at all sites. Conversely, when flows were high, the ratio was low, reflecting increased TP associated with particulate matter during high flows. Parma exhibited the highest OP:TP ratio during all seasons, at least 0.60 in spring and nearly 0.90 in autumn. Similar OP:TP ratios were estimated at Glenwood. Whereas the OP:TP ratio for Parma and Glenwood peaked in November or December, decreased from January through May, and increased again after June, estimates for Diversion showed nearly the opposite pattern ? ratios were highest in July and lowest in January and February. This difference might reflect complex biological and geochemical processes involving nutrient cycling in Lucky Peak Lake, but further data are needed to substantiate this hypothesis. Estimated monthly average SS loads were highest at Diversion, about 400 tons per day (ton/d). Average annual loads from 1994 through 2002 were 144,000 tons at Diversion, 33,000 tons at Glenwood, and 88,000 tons at Parma. Estimated SS loads peaked in the spring at all sites, coinciding with high flows. Increases in TP in the reach from Diversion to Glenwood ranged from 200 to 350 lb/d. Decreases in TP were small in this reach only during high flows in January and February 1997. Decreases in SS, were large during high-flow conditions indicating sediment deposition in the reach. Intermittent data at Middleton indicated that increases and decreases in TP in the reach from Glenwood to Middleton were during low- and high-flow conditions, respectively. All constituents increased in the r

Rating curve estimation of nutrient loads in Iowa rivers

USGS Publications Warehouse

Stenback, G.A.; Crumpton, W.G.; Schilling, K.E.; Helmers, M.J.

2011-01-01

Accurate estimation of nutrient loads in rivers and streams is critical for many applications including determination of sources of nutrient loads in watersheds, evaluating long-term trends in loads, and estimating loading to downstream waterbodies. Since in many cases nutrient concentrations are measured on a weekly or monthly frequency, there is a need to estimate concentration and loads during periods when no data is available. The objectives of this study were to: (i) document the performance of a multiple regression model to predict loads of nitrate and total phosphorus (TP) in Iowa rivers and streams; (ii) determine whether there is any systematic bias in the load prediction estimates for nitrate and TP; and (iii) evaluate streamflow and concentration factors that could affect the load prediction efficiency. A commonly cited rating curve regression is utilized to estimate riverine nitrate and TP loads for rivers in Iowa with watershed areas ranging from 17.4 to over 34,600km2. Forty-nine nitrate and 44 TP datasets each comprising 5-22years of approximately weekly to monthly concentrations were examined. Three nitrate data sets had sample collection frequencies averaging about three samples per week. The accuracy and precision of annual and long term riverine load prediction was assessed by direct comparison of rating curve load predictions with observed daily loads. Significant positive bias of annual and long term nitrate loads was detected. Long term rating curve nitrate load predictions exceeded observed loads by 25% or more at 33% of the 49 measurement sites. No bias was found for TP load prediction although 15% of the 44 cases either underestimated or overestimate observed long-term loads by more than 25%. The rating curve was found to poorly characterize nitrate and phosphorus variation in some rivers. ?? 2010 .

Explanatory characteristics for nutrient concentrations and loads in the Sava River Catchment and cross-regionally

NASA Astrophysics Data System (ADS)

Levi, L.; Cvetkovic, V.; Destouni, G.

2015-12-01

This study compiles estimates of waterborne nutrient concentrations and loads in the Sava River Catchment (SRC). Based on this compilation, we investigate hotspots of nutrient inputs and retention along the river, as well as concentration and load correlations with river discharge and various human drivers of excess nutrient inputs to the SRC. For cross-regional assessment and possible generalization, we also compare corresponding results between the SRC and the Baltic Sea Drainage Basin (BSDB). In the SRC, one small incremental subcatchment, which is located just downstream of Zagreb and has the highest population density among the SRC subcatchments, is identified as a major hotspot for net loading (input minus retention) of both total nitrogen (TN) and total phosphorus (TP) to the river and through it to downstream areas of the SRC. The other SRC subcatchments exhibit relatively similar characteristics with smaller net nutrient loading. The annual loads of both TN and TP along the Sava River exhibit dominant temporal variability with considerably higher correlation with annual river discharge (R2 = 0.51 and 0.28, respectively) than that of annual average nutrient concentrations (R2 = 0.0 versus discharge for both TN and TP). Nutrient concentrations exhibit instead dominant spatial variability with relatively high correlation with population density among the SRC subcatchments (R2=0.43-0.64). These SRC correlation characteristics compare well with corresponding ones for the BSDB, even though the two regions are quite different in their hydroclimatic, agricultural and wastewater treatment conditions. Such cross-regional consistency in dominant variability type and explanatory catchment characteristics may be a useful generalization basis, worthy of further investigation, for at least first-order estimation of nutrient concentration and load conditions in less data-rich regions.

Characteristics of Sediment Transportation in Two Contrasting Oak Forested Watersheds in the Lesser Central Himalaya, India

NASA Astrophysics Data System (ADS)

Qazi, N. U. Q.; Bruijnzeel, S., Sr.; Rai, S. P., Sr.

2015-12-01

Sediment transfer from mountainous areas to lowland areas is one of the most important geomorphological processes globally with the bulk of the sediment yield from such areas typically deriving from mass wastage processes. This study presents monthly, seasonal and annual variations in sediment transport (both suspended load and bedload) as well as dissolved loads over three consecutive water years (2008-2011) for two small forested watersheds with contrasting levels of forest disturbance in the Lesser Himalaya of Northwest India. Seasonal and annual suspended sediment yields were strongly influenced by amounts of rainfall and streamflow and showed a 10-63 fold range between wet and dry years. Of the annual load, some 93% was produced on average during the monsoon season (June-September). Sediment production by the disturbed forest catchment was 1.9-fold (suspended sediment) to 5.9-fold (bedload) higher than that for the well-stocked forest catchment. By contrast, dissolved loads varied much less between years, seasons (although minimal during the dry summer season), and degree of forest disturbance. Total mechanical denudation rates were 1.6 times and 4.6 times larger than chemical denudation rates for the little disturbed and the heavily disturbed forest catchment, respectively whereas overall denudation rates were estimated at 0.69 and 1.04 mm per 1000 years, respectively.

Analysis of trends of water quality and streamflow in the Blackstone, Branch, Pawtuxet, and Pawcatuck Rivers, Massachusetts and Rhode Island, 1979 to 2015

USGS Publications Warehouse

Savoie, Jennifer G.; Mullaney, John R.; Bent, Gardner C.

2017-02-21

Trends in long-term water-quality and streamflow data from six water-quality-monitoring stations within three major river basins in Massachusetts and Rhode Island that flow into Narragansett Bay and Little Narragansett Bay were evaluated for water years 1979–2015. In this study, conducted by the U.S. Geological Survey in cooperation with the Rhode Island Department of Environmental Management, the Rhode Island Water Resources Board, and the U.S. Environmental Protection Agency, water-quality and streamflow data were evaluated with a Weighted Regressions on Time, Discharge, and Season smoothing method, which removes the effects of year-to-year variation in water-quality conditions due to variations in streamflow (discharge). Trends in annual mean, annual median, annual maximum, and annual 7-day minimum flows at four continuous streamgages were evaluated by using a time-series smoothing method for water years 1979–2015.Water quality at all monitoring stations changed over the study period. Decreasing trends in flow-normalized nutrient concentrations and loads were observed during the period at most monitoring stations for total nitrogen, nitrite plus nitrate, and total phosphorus. Average flow-normalized loads for water years 1979–2015 decreased in the Blackstone River by up to 46 percent in total nitrogen, 17 percent in nitrite plus nitrate, and 69 percent in total phosphorus. The other rivers also had decreasing flow-normalized trends in nutrient concentrations and loads, except for the Pawtuxet River, which had an increasing trend in nitrite plus nitrate. Increasing trends in flow-normalized chloride concentrations and loads were observed during the study period at all of the rivers, with increases of more than 200 percent in the Blackstone River.Small increasing trends in annual mean daily streamflow were observed in 3 of the 4 rivers, with increases of 1.2 to 11 percent; however, the trends were not significant. All 4 rivers had decreases in streamflow for the annual 7-day minimums, but only 3 of the 4 rivers had decreases that were significant (34 to 54 percent). The Branch River had decreasing annual mean daily streamflow (7.5 percent) and the largest decrease in the annual 7-day minimum streamflow. The Blackstone and Pawtuxet Rivers had the largest increases in annual maximum daily flows but had decreases in the annual 7-day minimum flows.

Global baseline data on phosphorus pollution of large lakes

NASA Astrophysics Data System (ADS)

Fink, Gabriel; Flörke, Martina; Alcamo, Joseph

2016-04-01

Lakes are exposed to harmful eutrophication which is the most concerning water quality issue on global scale. Eutrophication is caused by phosphorous pollution in most lakes. Hence, global consistent base line data on phosphorus loadings are needed to assess future sustainable development. We used the modeling framework WaterGAP3 to calculate present total phosphorus loadings to the world's largest lakes. Estimates of modeled total phosphorus (TP) loadings as well as the contributions of different sectors were successfully validated against measured data. Based on these findings, annual total phosphorus loadings to lakes were calculated for diffuse and point sources according to the different sectors domestic, manufacturing, urban surface runoff, agriculture and background for the time period 1990 to 2010. Our results show high phosphorus loadings into lakes in southern latitudes. On global average, industrial fertilizer is the main anthropogenic source while background loadings are low in comparison. Nevertheless, both features indicate a high potential to reduce the exposure to eutrophication in lakes which are faced with high phosphor inputs. The global average of TP loadings was 7% higher in the time period 2005-2010 than in the period 1990-1995. The global average in 2005-2010 results from an increase in TP loadings of 79% in South America, which was dampened by a decrease in Europe, North America, and Asia. Chinese lakes were exposed to massive increasing phosphorus loadings, too. Both increasing and decreasing trends are caused primarily by changing industrial fertilizer application rates. In conclusion, this study provides a consistent and model based synopsis of global trends and sources of phosphorus loadings to large lakes. The estimates of phosphorus pollution of lakes present a basis for assessing and managing the global eutrophication problem.

Crustal Displacements Due to Continental Water Loading

NASA Technical Reports Server (NTRS)

vanDam, T.; Wahr, J.; Milly, P. C. D.; Shmakin, A. B.; Blewitt, G.; Lavallee, D.; Larson, K. M.

2001-01-01

The effects of long-wavelength (> 100 km), seasonal variability in continental water storage on vertical crustal motions are assessed. The modeled vertical displacements (delta-r(sub M)) have root-mean-square (RMS) values for 1994-1998 as large as 8 mm with ranges up to 30 mm, and are predominantly annual in character. Regional strains are on the order of 20 nanostrain for tilt and 5 nanostrain for horizontal deformation. We compare delta-r(sub M) with observed Global Positioning System (GPS) heights (delta-r(sub O)) (which include adjustments to remove estimated effects of atmospheric pressure and annual tidal and non-tidal ocean loading) for 147 globally distributed sites. When the delta-r(sub O) time series are adjusted by delta-r(sub M), their variances are reduced, on average, by an amount equal to the variance of the delta-r(sub M). Of the delta-r(sub O) time series exhibiting a strong annual signal, more than half are found to have an annual harmonic that is in phase and of comparable amplitude with the annual harmonic in the delta-r(sub M). The delta-r(sub M) time series exhibit long-period variations that could be mistaken for secular tectonic trends or post-glacial rebound when observed over a time span of a few years.

Atmospheric nitrogen deposition to China: a model analysis on nitrogen budget and critical load exceedance

NASA Astrophysics Data System (ADS)

Zhao, Y.; Zhang, L.; Chen, Y.; Liu, X.; Xu, W.; Pan, Y.; Duan, L.

2016-12-01

We present a national-scale model analysis of the sources and processes of inorganic nitrogen deposition over China using the GEOS-Chem model at 1/2°×1/3° horizontal resolution. Averaged model results for 2008-2012 are evaluated with an ensemble of surface measurements of nitrogen wet deposition flux and concentration, and satellite measurements of tropospheric NO2 columns. Annual inorganic nitrogen deposition fluxes are shown to be generally less than 10 kg N ha-1 a-1 in the western China, 15-50 kg N ha-1 a-1 in the eastern China, and 15.6 kg N ha-1 a-1 averaged over China. The model simulates an annual total deposition flux of 16.4 Tg N to China, with 10.3 Tg N (63%) from reduced nitrogen (NHx) and 6.2 Tg N from oxidized nitrogen (NOy). Domestic anthropogenic sources contribute 86% of the total deposition; foreign anthropogenic sources 7% and natural sources 7%. Annually 23% of domestically emitted NH3 and 36% for NOx are exported out of China. We also find while nitrogen deposition to China is comparable to the nitrogen input from fertilizer application (16.5 Tg N a-1) on the national scale, it is much more widely distributed spatially. The deposition flux is also much higher than natural biological fixation (7.3 Tg N a-1). A comparison with estimates of nitrogen critical load for eutrophication indicates that about 40% of the land over China faces nitrogen critical load exceedances. However, 45% of the exceeding areas, mainly in Beijing-Tianjin-Hebei, Central China, East China, and South China, will not occur in the absence of nitrogen deposition, demonstrating the necessity of nitrogen emission controls to avoid potential negative ecological effects over these areas.

Sediment Loading from Crab Creek and Other Sources to Moses Lake, Washington, 2007 and 2008

USGS Publications Warehouse

Magirl, Christopher S.; Cox, Stephen E.; Mastin, Mark C.; Huffman, Raegan L.

2010-01-01

The average sediment-accumulation rate on the bed of Moses Lake since 1980, based on the identification of Mount St. Helens ash in lakebed cores, was 0.24 inches per year. Summed over the lake surface area, the average sediment-accumulation rate on the lakebed is 190,000 tons per year. Based on USGS stream-gaging station data, the average annual sediment load to Moses Lake from Crab Creek was 32,000 tons per year between 1943 and 2008; the post Mount St. Helens eruption annual load from Crab Creek was calculated to be 13,000 tons per year. The total mass input from Crab Creek and other fluvially derived sediment sources since 1980 has been about 20,000 tons per year. Eolian sediment loading to Moses Lake was about 50,000 tons per year before irrigation and land-use development largely stabilized the Moses Lake dune field. Currently, eolian input to the lake is less than 2,000 tons per year. Considering all sediment sources to the lake, most (from 80 to 90 percent) of post-1980 lakebed-sediment accumulation is from autochthonous, or locally formed, mineral matter, including diatom frustuals and carbonate shells, derived from biogenic production in phytoplankton and zooplankton. Suspended-sediment samples collected from Crab Creek and similar nearby waterways in 2007 and 2008 combined with other USGS data from the region indicated that a proposed Bureau of Reclamation supplemental feed of as much as 650 cubic feet per second through Crab Creek might initially contain a sediment load of as much as 1,500 tons per day. With time, however, this sediment load would decrease to about 10 tons per day in the sediment-supply-limited creek as available sediment in the channel is depleted. Sediment loads in the supplemental feed ultimately would be similar to loads in other bypass canals near Moses Lake. Considering the hydrology and geomorphology of the creek over multiple years, there is little evidence that the proposed supplemental feed would substantially increase the overall sediment load from Crab Creek to Moses Lake relative to natural, background conditions. Because Moses Lake is relatively shallow and subject to significant wind-driven circulation currents, mixing also would redistribute some of the fluvial sediment load deposited from Crab Creek throughout Parker Horn and the rest of Moses Lake, further mitigating the local effect of Crab Creek sedimentation near the City of Moses Lake.

Nutrient additions by waterfowl to lakes and reservoirs: predicting their effects on productivity and water quality

USGS Publications Warehouse

Manny, Bruce A.; Johnson, W.C.; Wetzel, R.G.

1994-01-01

Lakes and reservoirs provide water for human needs and habitat for aquatic birds. Managers of such waters may ask whether nutrients added by waterfowl degrade water quality. For lakes and reservoirs where primary productivity is limited by phosphorus (P), we developed a procedure that integrates annual P loads from waterfowl and other external sources, applies a nutrient load-response model, and determines whether waterfowl that used the lake or reservoir degraded water quality. Annual P loading by waterfowl can be derived from a figure in this report, using the days per year that each kind spent on any lake or reservoir. In our example, over 6500 Canada geese (Branta canadensis) and 4200 ducks (mostly mallards, Anas platyrhynchos) added 4462 kg of carbon (C), 280 kg of nitrogen (N), and 88 kg of P y-1 to Wintergreen Lake in southwestern Michigan, mostly during their migration. These amounts were 69% of all C, 27% of all N, and 70% of all P that entered the lake from external sources. Loads from all external sources totaled 840 mg P m-2 y-1. Application of a nutrient load-response model to this concentration, the hydraulic load (0.25 m y-1), and the water residence time (9.7 y) of Wintergreen Lake yielded an average annual concentration of total P in the lake of 818 mg m-3 that classified the lake as hypertrophic. This trophic classification agreed with independent measures of primary productivity, chlorophyll-a, total P, total N, and Secchi disk transparency made in Wintergreen Lake. Our procedure showed that waterfowl caused low water quality in Wintergreen Lake.

Effects of brush management on the hydrologic budget and water quality in and adjacent to Honey Creek State Natural Area, Comal County, Texas, 2001-10

USGS Publications Warehouse

Banta, J. Ryan; Slattery, Richard N.

2011-01-01

The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Natural Resources Conservation Service, the Edwards Region Grazing Lands Conservation Initiative, the Texas State Soil and Water Conservation Board, the San Antonio River Authority, the Edwards Aquifer Authority, Texas Parks and Wildlife, the Guadalupe Blanco River Authority, and the San Antonio Water System, evaluated the hydrologic effects of ashe juniper (Juniperus ashei) removal as a brush management conservation practice in and adjacent to the Honey Creek State Natural Area in Comal County, Tex. By removing the ashe juniper and allowing native grasses to reestablish in the area as a brush management conservation practice, the hydrology in the watershed might change. Using a simplified mass balance approach of the hydrologic cycle, the incoming rainfall was distributed to surface water runoff, evapotranspiration, or groundwater recharge. After hydrologic data were collected in adjacent watersheds for 3 years, brush management occurred on the treatment watershed while the reference watershed was left in its original condition. Hydrologic data were collected for another 6 years. Hydrologic data include rainfall, streamflow, evapotranspiration, and water quality. Groundwater recharge was not directly measured but potential groundwater recharge was calculated using a simplified mass balance approach. The resulting hydrologic datasets were examined for differences between the watersheds and between pre- and post-treatment periods to assess the effects of brush management. The streamflow to rainfall relation (expressed as event unit runoff to event rainfall relation) did not change between the watersheds during pre- and post-treatment periods. The daily evapotranspiration rates at the reference watershed and treatment watershed sites exhibited a seasonal cycle during the pre- and post-treatment periods, with intra- and interannual variability. Statistical analyses indicate the mean difference in daily evapotranspiration rates between the two watershed sites is greater during the post-treatment than the pre-treatment period. Average annual rainfall, streamflow, evapotranspiration, and potential groundwater-recharge conditions were incorporated into a single hydrologic budget (expressed as a percentage of the average annual rainfall) applied to each watershed before and after treatment to evaluate the effects of brush management. During the post-treatment period, the percent average annual unit runoff in the reference watershed was similar to that in the treatment watershed, however, the difference in percentages of average annual evapotranspiration and potential groundwater recharge were more appreciable between the reference and treatment watersheds than during the pre-treatment period. Using graphical comparisons, no notable differences in major ion or nutrient concentrations were found between samples collected at the reference watershed (site 1C) and treatment watershed (site 2C) during pre- and post-treatment periods. Suspended-sediment loads were calculated from samples collected at sites 1C and 2T. The relation between suspended-sediment loads and streamflow calculated from samples collected from sites 1C and 2T did not exhibit a statistically significant difference during the pre-treatment period, whereas during the post-treatment period, relation between suspended-sediment loads and streamflow did exhibit a statistically significant difference. The suspended-sediment load to streamflow relations indicate that for the same streamflow, the suspended-sediment loads calculated from site 2T were generally less than suspended-sediment loads calculated from site 1C during the post-treatment period.

Quantifying watershed-scale groundwater loading and in-stream fate of nitrate using high-frequency water quality data

USGS Publications Warehouse

Miller, Matthew P.; Tesoriero, Anthony J.; Capel, Paul D.; Pellerin, Brian A.; Hyer, Kenneth E.; Burns, Douglas A.

2016-01-01

We describe a new approach that couples hydrograph separation with high-frequency nitrate data to quantify time-variable groundwater and runoff loading of nitrate to streams, and the net in-stream fate of nitrate at the watershed-scale. The approach was applied at three sites spanning gradients in watershed size and land use in the Chesapeake Bay watershed. Results indicate that 58-73% of the annual nitrate load to the streams was groundwater-discharged nitrate. Average annual first order nitrate loss rate constants (k) were similar to those reported in both modelling and in-stream process-based studies, and were greater at the small streams (0.06 and 0.22 d-1) than at the large river (0.05 d-1), but 11% of the annual loads were retained/lost in the small streams, compared with 23% in the large river. Larger streambed area to water volume ratios in small streams result in greater loss rates, but shorter residence times in small streams result in a smaller fraction of nitrate loads being removed than in larger streams. A seasonal evaluation of k values suggests that nitrate was retained/lost at varying rates during the growing season. Consistent with previous studies, streamflow and nitrate concentration were inversely related to k. This new approach for interpreting high-frequency nitrate data and the associated findings furthers our ability to understand, predict, and mitigate nitrate impacts on streams and receiving waters by providing insights into temporal nitrate dynamics that would be difficult to obtain using traditional field-based studies.

Determining storm sampling requirements for improving precision of annual load estimates of nutrients from a small forested watershed.

PubMed

Ide, Jun'ichiro; Chiwa, Masaaki; Higashi, Naoko; Maruno, Ryoko; Mori, Yasushi; Otsuki, Kyoichi

2012-08-01

This study sought to determine the lowest number of storm events required for adequate estimation of annual nutrient loads from a forested watershed using the regression equation between cumulative load (∑L) and cumulative stream discharge (∑Q). Hydrological surveys were conducted for 4 years, and stream water was sampled sequentially at 15-60-min intervals during 24 h in 20 events, as well as weekly in a small forested watershed. The bootstrap sampling technique was used to determine the regression (∑L-∑Q) equations of dissolved nitrogen (DN) and phosphorus (DP), particulate nitrogen (PN) and phosphorus (PP), dissolved inorganic nitrogen (DIN), and suspended solid (SS) for each dataset of ∑L and ∑Q. For dissolved nutrients (DN, DP, DIN), the coefficient of variance (CV) in 100 replicates of 4-year average annual load estimates was below 20% with datasets composed of five storm events. For particulate nutrients (PN, PP, SS), the CV exceeded 20%, even with datasets composed of more than ten storm events. The differences in the number of storm events required for precise load estimates between dissolved and particulate nutrients were attributed to the goodness of fit of the ∑L-∑Q equations. Bootstrap simulation based on flow-stratified sampling resulted in fewer storm events than the simulation based on random sampling and showed that only three storm events were required to give a CV below 20% for dissolved nutrients. These results indicate that a sampling design considering discharge levels reduces the frequency of laborious chemical analyses of water samples required throughout the year.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ferguson, D.W.; Tompkins, T.A.; Pratapas, J.M.

The Coal Quality Impact Model (CQIM{trademark}) was used to evaluate the economic and performance impacts of gas co-firing at Mississippi Power Company`s Plant Watson. One of the most important benefits of gas co-firing considered was the ability to burn lower quality, less expensive fuels. Four coals and petroleum coke were evaluated at 0, 5, 10, 20, and 30 percent gas co-firing. These fuels vary widely in their geographic source, heating value, moisture, volatile matter, and sulfur contents. Performance and economic evaluations were conducted at individual load points of 100, 75, 50, 40, 30, and 20 percent of full load. Additionalmore » analyses were made for seasonal load-demand curves and for an average annual load-demand curve. Operating cost in $/MWh, net plant heat rate in Btu/kWh, and break-even gas price in $/MBtu are presented as a function of load and percent gas co-firing. Results illustrate that with the Illinois Basin Coal currently burned at Plant Watson, gas co-firing can be economically justified over a range of gas market prices on either an annual or seasonal basis. Other findings indicate that petroleum coke and South American coal co-fired with natural gas offer significant fuel cost savings and are attractive candidate fuels for combustion verification testing.« less

Use of the USEPA Estuary Nitrogen Model to Estimate Concentrations of Total Nitrogen in Estuaries Using Loads Calculated by Watershed Models and Monitoring Data

EPA Science Inventory

We use USEPA’s Estuary Nitrogen Model (ENM) to calculate annual average concentrations of total nitrogen (TN) in ten estuaries or sub-estuaries along the Atlantic coast from New Hampshire to Florida. These include a variety of systems, ranging from strongly-flushed bays to weakly...

Seasonal Phosphorus Sources and Loads to Upper Klamath Lake, Oregon, as Determined by a Dynamic SPARROW Model

NASA Astrophysics Data System (ADS)

Saleh, D.; Domagalski, J. L.; Smith, R. A.

2016-12-01

The SPARROW (SPAtially-Referenced Regression On Watershed Attributes) model, developed by the U.S. Geological Survey, has been used to identify and quantify the sources of nitrogen and phosphorus in watersheds and to predict their fluxes and concentration at specified locations downstream. Existing SPARROW models use a hybrid statistical approach to describe an annual average ("steady-state") relationship between sources and stream conditions based on long-term water quality monitoring data and spatially-referenced explanatory information. Although these annual models are useful for some management purposes, many water quality issues stem from intra- and inter-annual changes in constituent sources, hydrologic forcing, or other environmental conditions, which cause a lag between watershed inputs and stream water quality. We are developing a seasonal dynamic SPARROW model of sources, fluxes, and yields of phosphorus for the watershed (approximately 9,700 square kilometers) draining to Upper Klamath Lake, Oregon. The lake is hyper-eutrophic and various options are being considered for water quality improvement. The model was calibrated with 11 years of water quality data (2000 to 2010) and simulates seasonal loads and yields for a total of 44 seasons. Phosphorus sources to the watershed include animal manure, farm fertilizer, discharges of treated wastewater, and natural sources (soil and streambed sediment). The model predicts that phosphorus delivery to the lake is strongly affected by intra- and inter-annual changes in precipitation and by temporary seasonal storage of phosphorus in the watershed. The model can be used to predict how different management actions for mitigating phosphorus sources might affect phosphorus loading to the lake as well as the time required for any changes in loading to occur following implementation of the action.

Sediment characteristics of small streams in southern Wisconsin, 1954-59

USGS Publications Warehouse

Collier, Charles R.

1963-01-01

The results of investigations of the sediment and water discharge characteristics of Black Earth Creek, Mount Vernon Creek, and Yellowstone River from 1954 to 1959 and Dell Creek for 1958 and 1959 indicate large differences in annual runoff and sediment yields. The suspended-sediment discharge of Black Earth Creek averaged 3,260 tons per year or 71 tons per square mile : the annual yields ranged from 27 to 102 tons per square mile. The annual suspended-sediment yield of Mount Vernon Creek ranged from 48 to 171 tons per square mile and averaged 96 tons per square mile. The maximum daily discharge was 1,120 tons on April 1, 1960, during a storm which produced 67 percent of the suspended load for that water year and exceeded the discharge for the preceding 3 years. The sediment discharge of the Yellowstone River averaged 6,870 tons per year or 236 tons per square riffle. The maximum daily sediment discharge, 3,750 tons on April 1, 1959, occurred during a 14-day period of high flow during which the sediment discharge was 15,480 tons. In 1958 and 1959, Dell Creek had suspended-sediment yields of 4.7 and 26 tons per square mile of drainage area. The suspended sediment transported by Black Earth and Mount Vernon Creeks is about two-thirds clay and one-third silt. For Yellowstone River the particle-size distribution of the suspended sediment ranged from three-fourths clay and one-fourth silt during periods of low sediment discharge to one-third clay and two-thirds silt during high sediment discharges. For Dell Creek nearly all of the suspended sediment is clay, but the bed load is sand. The mean sediment concentration of storm runoff averaged two to three times more in the summer than in the winter. No significant changes with time occurred in the relation between storm runoff and sediment yield.

Comparison of Mercury Mass Loading in Streams to Wet and Dry Atmospheric Deposition in Watersheds of the Western US: Evidence for Non-Atmospheric Mercury Sources

NASA Astrophysics Data System (ADS)

Domagalski, J. L.; Majewski, M. S.; Alpers, C. N.; Eckley, C.

2015-12-01

Many streams in the western United States (US) are listed as impaired by mercury (Hg), and it is important to understand the magnitudes of the various sources in order to implement management strategies. Atmospheric deposition of Hg and can be a major source of aquatic contamination, along with mine wastes, and other sources. Prior studies in the eastern US have shown that streams deliver less than 50% of the atmospherically deposited Hg on an annual basis. In this study, we compared annual stream Hg loads for 20 watersheds in the western US to measured wet and modeled dry deposition. Land use varies from undisturbed to mixed (agricultural, urban, forested, mining). Data from the Mercury Deposition Network was used to estimate Hg input from precipitation. Dry deposition was not directly measured, but can be modeled using the Community Multi-scale Air Quality model. At an undeveloped watershed in the Rocky Mountains, the ratio of stream Hg load to atmospheric deposition was 0.2 during a year of average precipitation. In contrast, at the Carson River in Nevada, with known Hg contamination from historical silver mining with Hg amalgamation, stream export exceeded atmospheric deposition by a factor of 60, and at a small Sierran watershed with gold mining, the ratio was 70. Larger watersheds with mixed land uses, tend to have lower ratios of stream export relative to atmospheric deposition suggesting storage of Hg. The Sacramento River was the largest watershed for which Hg riverine loads were available with an average ratio of stream Hg export to atmospheric deposition of 0.10. Although Hg was used in upstream historical mining operations, the downstream river Hg load is partially mitigated by reservoirs, which trap sediment. This study represents the first compilation of riverine Hg loads in comparison to atmospheric deposition on a regional scale; the approach may be useful in assessing the relative importance of atmospheric and non-atmospheric Hg sources.

Suspended sediment delivery to Puget Sound from the lower Nisqually River, western Washington, July 2010–November 2011

USGS Publications Warehouse

Curran, Christopher A.; Grossman, Eric E.; Magirl, Christopher S.; Foreman, James R.

2016-05-26

On average, the Nisqually River delivers about 100,000 metric tons per year (t/yr) of suspended sediment to Puget Sound, western Washington, a small proportion of the estimated 1,200,000 metric tons (t) of sediment reported to flow in the upper Nisqually River that drains the glaciated, recurrently active Mount Rainier stratovolcano. Most of the upper Nisqually River sediment load is trapped in Alder Lake, a reservoir completed in 1945. For water year 2011 (October 1, 2010‒September 30, 2011), daily sediment and continuous turbidity data were used to determine that 106,000 t of suspended sediment were delivered to Puget Sound, and 36 percent of this load occurred in 2 days during a typical winter storm. Of the total suspended-sediment load delivered to Puget Sound in the water year 2011, 47 percent was sand (particle size >0.063 millimeters), and the remainder (53 percent) was silt and clay. A sediment-transport curve developed from suspended-sediment samples collected from July 2010 to November 2011 agreed closely with a curve derived in 1973 using similar data-collection methods, indicating that similar sediment-transport conditions exist. The median annual suspended-sediment load of 73,000 t (water years 1980–2014) is substantially less than the average load, and the correlation (Pearson’s r = 0.80, p = 8.1E-9, n=35) between annual maximum 2-day sediment loads and normalized peak discharges for the period indicates the importance of wet years and associated peak discharges of the lower Nisqually River for sediment delivery to Puget Sound. The magnitude of peak discharges in the lower Nisqually River generally is suppressed by flow regulation, and relative to other free-flowing, glacier-influenced rivers entering Puget Sound, the Nisqually River delivers proportionally less sediment because of upstream sediment trapping from dams.

2013 Gulf of Mexico Hypoxia Forecast

USGS Publications Warehouse

Scavia, Donald; Evans, Mary Anne; Obenour, Dan

2013-01-01

The Gulf of Mexico annual summer hypoxia forecasts are based on average May total nitrogen loads from the Mississippi River basin for that year. The load estimate, recently released by USGS, is 7,316 metric tons per day. Based on that estimate, we predict the area of this summer’s hypoxic zone to be 18,900 square kilometers (95% credible interval, 13,400 to 24,200), the 7th largest reported and about the size of New Jersey. Our forecast hypoxic volume is 74.5 km3 (95% credible interval, 51.5 to 97.0), also the 7th largest on record.

Response of Colorado river runoff to dust radiative forcing in snow

USGS Publications Warehouse

Painter, T.H.; Deems, J.S.; Belnap, J.; Hamlet, A.F.; Landry, C.C.; Udall, B.

2010-01-01

The waters of the Colorado River serve 27 million people in seven states and two countries but are overallocated by more than 10% of the river's historical mean. Climate models project runoff losses of 7-20% from the basin in this century due to human-induced climate change. Recent work has shown however that by the late 1800s, decades prior to allocation of the river's runoff in the 1920s, a fivefold increase in dust loading from anthropogenically disturbed soils in the southwest United States was already decreasing snow albedo and shortening the duration of snow cover by several weeks. The degree to which this increase in radiative forcing by dust in snow has affected timing and magnitude of runoff from the Upper Colorado River Basin (UCRB) is unknown. Hereweuse the Variable Infiltration Capacity model with postdisturbance and predisturbance impacts of dust on albedo to estimate the impact on runoff from the UCRB across 1916-2003. We find that peak runoff at Lees Ferry, Arizona has occurred on average 3 wk earlier under heavier dust loading and that increases in evapotranspiration from earlier exposure of vegetation and soils decreases annual runoff by more than 1.0 billion cubic meters or ???5% of the annual average. The potential to reduce dust loading through surface stabilization in the deserts and restore more persistent snow cover, slow runoff, and increase water resources in the UCRB may represent an important mitigation opportunity to reduce system management tensions and regional impacts of climate change.

Ecosystem-Service Tradeoffs Associated with Switching from Annual to Perennial Energy Crops in Riparian Zones of the US Midwest

PubMed Central

Meehan, Timothy D.; Gratton, Claudio; Diehl, Erica; Hunt, Natalie D.; Mooney, Daniel F.; Ventura, Stephen J.; Barham, Bradford L.; Jackson, Randall D.

2013-01-01

Integration of energy crops into agricultural landscapes could promote sustainability if they are placed in ways that foster multiple ecosystem services and mitigate ecosystem disservices from existing crops. We conducted a modeling study to investigate how replacing annual energy crops with perennial energy crops along Wisconsin waterways could affect a variety of provisioning and regulating ecosystem services. We found that a switch from continuous corn production to perennial-grass production decreased annual income provisioning by 75%, although it increased annual energy provisioning by 33%, decreased annual phosphorous loading to surface water by 29%, increased below-ground carbon sequestration by 30%, decreased annual nitrous oxide emissions by 84%, increased an index of pollinator abundance by an average of 11%, and increased an index of biocontrol potential by an average of 6%. We expressed the tradeoffs between income provisioning and other ecosystem services as benefit-cost ratios. Benefit-cost ratios averaged 12.06 GJ of additional net energy, 0.84 kg of avoided phosphorus pollution, 18.97 Mg of sequestered carbon, and 1.99 kg of avoided nitrous oxide emissions for every $1,000 reduction in income. These ratios varied spatially, from 2- to 70-fold depending on the ecosystem service. Benefit-cost ratios for different ecosystem services were generally correlated within watersheds, suggesting the presence of hotspots – watersheds where increases in multiple ecosystem services would come at lower-than-average opportunity costs. When assessing the monetary value of ecosystem services relative to existing conservation programs and environmental markets, the overall value of enhanced services associated with adoption of perennial energy crops was far lower than the opportunity cost. However, when we monitized services using estimates for the social costs of pollution, the value of enhanced services far exceeded the opportunity cost. This disparity between recoverable costs and social value represents a fundamental challenge to expansion of perennial energy crops and sustainable agricultural landscapes. PMID:24223215

Ecosystem-service tradeoffs associated with switching from annual to perennial energy crops in riparian zones of the US Midwest.

PubMed

Meehan, Timothy D; Gratton, Claudio; Diehl, Erica; Hunt, Natalie D; Mooney, Daniel F; Ventura, Stephen J; Barham, Bradford L; Jackson, Randall D

2013-01-01

Integration of energy crops into agricultural landscapes could promote sustainability if they are placed in ways that foster multiple ecosystem services and mitigate ecosystem disservices from existing crops. We conducted a modeling study to investigate how replacing annual energy crops with perennial energy crops along Wisconsin waterways could affect a variety of provisioning and regulating ecosystem services. We found that a switch from continuous corn production to perennial-grass production decreased annual income provisioning by 75%, although it increased annual energy provisioning by 33%, decreased annual phosphorous loading to surface water by 29%, increased below-ground carbon sequestration by 30%, decreased annual nitrous oxide emissions by 84%, increased an index of pollinator abundance by an average of 11%, and increased an index of biocontrol potential by an average of 6%. We expressed the tradeoffs between income provisioning and other ecosystem services as benefit-cost ratios. Benefit-cost ratios averaged 12.06 GJ of additional net energy, 0.84 kg of avoided phosphorus pollution, 18.97 Mg of sequestered carbon, and 1.99 kg of avoided nitrous oxide emissions for every $1,000 reduction in income. These ratios varied spatially, from 2- to 70-fold depending on the ecosystem service. Benefit-cost ratios for different ecosystem services were generally correlated within watersheds, suggesting the presence of hotspots--watersheds where increases in multiple ecosystem services would come at lower-than-average opportunity costs. When assessing the monetary value of ecosystem services relative to existing conservation programs and environmental markets, the overall value of enhanced services associated with adoption of perennial energy crops was far lower than the opportunity cost. However, when we monitized services using estimates for the social costs of pollution, the value of enhanced services far exceeded the opportunity cost. This disparity between recoverable costs and social value represents a fundamental challenge to expansion of perennial energy crops and sustainable agricultural landscapes.

Nutrient Loading and Algal Response in West Thompson Lake, Thompson, Connecticut, 2003-2005

USGS Publications Warehouse

Morrison, Jonathan; Colombo, Michael J.

2008-01-01

Water quality and nutrient loads were characterized for parts of the Quinebaug River and West Thompson Lake in northeastern Connecticut during 2003 to 2005. The West Thompson Lake watershed is a mainly forested watershed that receives treated municipal wastewater from several point sources in Massachusetts. The lake is a flood-control reservoir formed in 1966 by impoundment of the Quinebaug River. Median concentrations of total phosphorus in two inflow (upstream) and one outflow (downstream) sampling stations on the Quinebaug River were higher than the nutrient criteria recommended by the U.S. Environmental Protection Agency (USEPA) for rivers and streams in aggregate Ecoregion XIV. In general, concentrations of total phosphorus in West Thompson Lake also were above the nutrient criteria recommended by USEPA for lakes and impoundments in aggregate Ecoregion XIV. The trophic status of West Thompson Lake has changed since 1995 from a hypereutrophic lake to a eutrophic lake; however, the lake still has large algal blooms. These blooms are predominated by blue-green algae, with chlorophyll-a concentrations of more than 30 micrograms per liter and algal cell counts as high as 73,000 cells/mL. Water samples collected during the summer of 2005 identified phosphorus as the primary limiting nutrient early in the season, but algal growth is probably co-limited by phosphorus and nitrogen later in the season. Lake-bottom sediments were collected from several areas throughout the lake and ranged in thickness from less than 1 foot (ft) to more than 3 ft. Concentrations of phosphorus in sediments differed throughout the lake; the highest values were found in the middle of the lake. Concentrations of total phosphorus also increased from an average 1,800 milligrams per kilogram (mg/kg) in the upper layers of sediment to more than 6,000 mg/kg at depth in the sediment. Annual, seasonal, and monthly loads and yields of nutrients were calculated for the three sampling locations on the Quinebaug River to develop a nutrient mass-balance model (budget) for West Thompson Lake. The average annual yields of total phosphorus during 2000 to 2005 were 115 pounds per square mile per year (lb/mi2/yr) at Quinebaug (inflow station), 116 lb/mi2/yr at Red Bridge Road (inflow station), and 97.9 lb/mi2/yr at West Thompson (outflow station). The 18-percent decrease in the average annual yield of total phosphorus between the inflow station at Red Bridge Road and the outlet of West Thompson Lake at West Thompson indicates that a significant part of the phosphorus load is retained in the lake. Annual yields of total phosphorus at Quinebaug have decreased significantly since the 1980s, from 362 lb/mi2/yr (for 1981-1990) to 115 lb/mi2/yr (1996-2005). The annual net export of phosphorus in West Thompson Lake during water years 2000 to 2005 ranged from -36 percent (2005) to 1 percent (2002) of the incoming load. Seasonal mass-balance data for total phosphorus during the summers of 2000 to 2003, when streamflow was at or lower than normal, indicated a net export of phosphorus that ranged from 3.4 percent (2003) to 30.7 percent (2002) of the incoming load. During the summer of 2004, however, streamflows were much higher than normal, and there was a negative export of phosphorus in West Thompson Lake of -3.9 percent. The annual net export of nitrogen in West Thompson Lake during water years 2000 to 2005 ranged from -5 percent (2002) to 4 percent (2001) of the incoming load. No clear pattern was evident to relate total nitrogen export to seasonal variables or runoff. Removal of phosphorus during the summer by wastewater-treatment plants (WWTPs) in Massachusetts reduces the concentration and load of total phosphorus entering West Thompson Lake in the summer; however, the large amount of phosphorus retained in the lake during the other seasons, in addition to the phosphorus stored in the lake-bottom sediments, may become available to fuel algal blooms in the lake

Nitrate and phosphorus transport through subsurface drains under free and controlled drainage.

PubMed

Saadat, Samaneh; Bowling, Laura; Frankenberger, Jane; Kladivko, Eileen

2018-05-28

Controlled drainage (CD) is a structural conservation practice in which the drainage outlet is managed in order to reduce drain flow volume and nutrient loads to water bodies. The goal of this study was to evaluate the potential of CD to improve water quality for two different seasons and levels of outlet control, using ten years of data collected from an agricultural drained field in eastern Indiana with two sets of paired plots. The Rank Sum test was used to quantify the impact of CD on cumulative annual drain flow and nitrate-N and phosphorus loads. CD plots had a statistically significant (at 5% level) lower annual drain flow (eastern pair: 39%; western pair: 25%) and nitrate load (eastern pair: 43%; western pair: 26%) compared to free draining (FD) plots, while annual soluble reactive phosphorus (SRP) and total phosphorus (TP) loads were not significantly different. An ANCOVA model was used to evaluate the impact of CD on daily drain flow, nitrate-N, SRP and TP concentrations and loads during the two different periods of control. The average percent reduction of daily drain flow was 68% in the eastern pair and 58% in the western pair during controlled drainage at the higher outlet level (winter) and 64% and 58% at the lower outlet level (summer) in the eastern and western pairs, respectively. Nitrate load reduction was similar to drain flow reduction, while the effect of CD on SRP and TP loads was not significant except for the increase in SRP in one pair. These results from a decade-long field monitoring and two different statistical methods enhance our knowledge about water quality impacts of CD system and support this management practice as a reliable system for reducing nitrate loss through subsurface drains, mainly caused by flow reduction. Copyright © 2018 Elsevier Ltd. All rights reserved.

Trend analysis of the homogenized total ozone series of Arosa (Switzerland), 1926-1996

NASA Astrophysics Data System (ADS)

Staehelin, Johannes; Kegel, Rainer; Harris, Neil R. P.

1998-04-01

Total ozone measurements have been made at Arosa, Switzerland (47°N), from 1926 through the present day, forming the longest total ozone series in the world. The record has been recently homogenized. Ozone trends are calculated to be -(2.3±0.6)% per decade for annual means (larger losses are found in winter and spring, approximately -4% per decade for trends in January, February, and March) when a simple linear change from 1970 to 1996 is assumed. In addition, total ozone trends are calculated using multiple regression models involving combinations of explanatory variables for the 11-year solar cycle, local meteorological conditions (the Mount Säntis high-altitude temperature record), stratospheric aerosol loading from volcanoes, and stratospheric chlorine loading. When the terms for the solar cycle, the stratospheric aerosol loading and the high mountain temperature record were included, the annually averaged ozone trends were found to be -(1.9±0.6)% per decade. While a statistically significant relation is found between total ozone and indices of aerosol loadings of the stratosphere, the recent decrease in total ozone cannot be accounted for by the higher average aerosol content in the second half of the century. Finally, the decrease in ozone in the stratosphere is estimated to be approximately 30% larger than that found for total ozone, when a crude estimate of the increase in tropospheric ozone is included. The acceleration observed in total ozone trends between the 1970s and the 1980s over northern midlatitudes [e.g., Harris et al., 1997] might be partially attributed to the larger increase in tropospheric ozone in the 1970s.

Effects of urban best management practices on streamflow and phosphorus and suspended-sediment transport on Englesby Brook in Burlington, Vermont, 2000-2010

USGS Publications Warehouse

Medalie, Laura

2012-01-01

An assessment of the effectiveness of several urban best management practice structures, including a wet extended detention facility and a shallow marsh wetland (together the "wet extended detention ponds"), was made using data collected from 2000 through 2010 at Englesby Brook in Burlington, Vermont. The purpose of the best management practices was to reduce high streamflows and phosphorus and suspended-sediment loads and concentrations and to increase low streamflows. Englesby Brook was monitored for streamflow, phosphorus, and suspended-sediment concentrations at a streamgage downstream of the best management practice structures for 5 years before the wet extended detention ponds were constructed in 2005 and for 4 years (phosphorus and suspended-sediment concentrations) or 5 years (streamflow) after they were constructed. The period after construction of the best management practice structures was wetter and had higher discharges than the period before construction. Despite the wetter conditions, streamflow duration curves provided evidence that the streamflow regime appeared to have shifted so that the percentages of low streamflows have increased and those of high streamflows may have slightly decreased. Two other hydrologic measures showed improvements in the years following construction of the best management practices: the percentage of annual discharge transported during the 3 days with highest discharges and the number of days with zero streamflow have both decreased. Evidence was mixed for the effectiveness of the best management practices in reducing phosphorus and suspended-sediment concentrations and loads. Annual phosphorus and suspended-sediment loads, monthly loads, low-streamflow concentrations, storm-averaged streamflow-adjusted concentrations, and total storm loads either did not change significantly or increased in the period after construction. These results likely were because of the wetter conditions in the period after construction. For example, monthly loads assessed using analysis of covariance, which compensated for the effects of streamflow on loads, suggested no difference in phosphorus or suspended-sediment loads between the two periods, whereas the comparison of monthly loads without factoring in streamflow showed an increase. This result could be viewed as evidence that the ponds may have mitigated the effect of greater discharges in the period after construction by preventing a corresponding increase in loads. In another analysis used to adjust for the difference in discharge between the two comparison periods, annual and monthly load results were grouped into dry and wet years. Large (50 percent) reductions in annual loads were observed when data from dry (or wet) years before construction were compared with data from dry (or wet) years after construction. When paired monthly loads of each constituent were grouped into dry and wet years, approximately the same number of months had increases as did decreases with the magnitudes of the decreases generally larger than the magnitudes of the increases. These differences in magnitude explain the decrease in annual loads for dry and wet years. The close association of phosphorus with suspended-sediment data suggested that most of the phosphorus was in the particulate form and was controlled by suspended-sediment dynamics.

49 CFR 1247.1 - Annual Report of Cars Loaded and Cars Terminated.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 9 2010-10-01 2010-10-01 false Annual Report of Cars Loaded and Cars Terminated... TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION (CONTINUED) ACCOUNTS, RECORDS AND REPORTS REPORT OF CARS LOADED AND CARS TERMINATED § 1247.1 Annual Report of Cars Loaded and Cars Terminated. Beginning with the...

49 CFR 1247.1 - Annual Report of Cars Loaded and Cars Terminated.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 9 2014-10-01 2014-10-01 false Annual Report of Cars Loaded and Cars Terminated... TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION (CONTINUED) ACCOUNTS, RECORDS AND REPORTS REPORT OF CARS LOADED AND CARS TERMINATED § 1247.1 Annual Report of Cars Loaded and Cars Terminated. Beginning with the...

49 CFR 1247.1 - Annual Report of Cars Loaded and Cars Terminated.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 9 2013-10-01 2013-10-01 false Annual Report of Cars Loaded and Cars Terminated... TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION (CONTINUED) ACCOUNTS, RECORDS AND REPORTS REPORT OF CARS LOADED AND CARS TERMINATED § 1247.1 Annual Report of Cars Loaded and Cars Terminated. Beginning with the...

49 CFR 1247.1 - Annual Report of Cars Loaded and Cars Terminated.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 9 2011-10-01 2011-10-01 false Annual Report of Cars Loaded and Cars Terminated... TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION (CONTINUED) ACCOUNTS, RECORDS AND REPORTS REPORT OF CARS LOADED AND CARS TERMINATED § 1247.1 Annual Report of Cars Loaded and Cars Terminated. Beginning with the...

49 CFR 1247.1 - Annual Report of Cars Loaded and Cars Terminated.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 9 2012-10-01 2012-10-01 false Annual Report of Cars Loaded and Cars Terminated... TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION (CONTINUED) ACCOUNTS, RECORDS AND REPORTS REPORT OF CARS LOADED AND CARS TERMINATED § 1247.1 Annual Report of Cars Loaded and Cars Terminated. Beginning with the...

Nitrogen Concentrations and Exports in Baseflow and Stormflow from Three Small Urban Catchments in Central Florida

NASA Astrophysics Data System (ADS)

Luo, J.; Hochmuth, G.; Clark, M. W.

2014-12-01

Export of nitrogen from different watersheds across the United States is receiving increasing attention due to the impairment of water quality in receiving water bodies. Researchers have indicated that different land uses exerted a substantial influence on the water quality. Nitrogen loadings on the watershed scale are being studied in many large ecosystems, such as the Baltimore Ecosystem and Arizona Ecosystem, but only a few focuses in a smaller scale such as catchment scale. Characterization of the land use in catchment scale can better explain the observed environmental phenomena under the watershed scale and enrich the related watershed studies. Nitrogen fluxes have been studied at Lake Alice watershed in Gainesville, Florida with a focus on the rarely studied catchments such as sports fields with intensive fertilization management (SFC), urban area with reclaimed water irrigation (RWC) and urban area without irrigation (CC). The entire study started from May 2013. Discharge was monitored in the three catchments by transducers every 5 minutes. Regular biweekly grab samples in the three catchments were used to estimate the baseflow N loads, composite samples in 13 storms were collected to estimate the stormflow N loads. The results showed that in the baseflow, the average NO3-N concentration in SFC was 12.19 mg/l, which was significantly different from the urban catchments. Also there was a significant difference between the NO3-N concentrations in RWC (1.17 mg/l on average) and CC (0.60 mg/l on average). A separate log-log relationship was developed between discharge and N loads to estimate the baseflow N loads and stormflow N loads. It showed that baseflow contributed more N loads than stormflow in the three catchments in the annual N load. In conclusion, the recreational catchment received the greatest N load compared to the other catchments, so it should be the priority catchment when it comes to adopting nutrient management practices in the Lake Alice watershed.

Concentrations and transport of atrazine in the Delaware River-Perry Lake system, northeast Kansas, July 1993 through September 1995

USGS Publications Warehouse

Pope, L.M.; Brewer, L.D.; Foley, G.A.; Morgan, S.C.

1996-01-01

A study of the distribution and transport of atrazine in surface water in the 1,117 square-mile Delaware River Basin in northeast Kansas was conducted from July 1992 through September 1995. The purpose of this report is to present information to assess the present (1992-95) conditions and possible future changes in the distribution and magnitude of atrazine concentrations, loads, and yields spatially, temporally, and in relation to hydrologic conditions and land-use characteristics. A network of 11 stream-monitoring and sample-collection sites was established within the basin. Stream- water samples were collected during a wide range of hydrologic conditions throughout the study. Nearly 5,000 samples were analyzed by enzyme- linked immunosorbent assay (ELISA) for triazine herbicide concentrations. Daily mean triazine herbicide concentrations were calculated for all sampling sites and subsequently used to estimate daily mean atrazine concentrations with a linear- regression relation between ELISA-derived triazine concentrations and atrazine concentrations determined by gas chromatography/mass spectrometry for 141 dual-analyzed surface-water samples. During May, June, and July, time-weighted, daily mean atrazine concentrations in streams in the Delaware River Basin commonly exceeded the value of 3.0-ug/L (micrograms per liter) annual mean Maximum Contaminant Level (MCL) established by the U.S. Environmental Protection Agency for drinking-water supplies. Time-weighted, daily mean concentrations equal to or greater than 20 ug/L were not uncommon. However, most time- weighted, daily mean concentrations were less than 1.0 ug/L from August through April. The largest time-weighted, monthly mean atrazine concentrations occurred during May, June, and July. Most monthly mean concentrations between August and April were less than 0.50 ug/L. Large differences were documented in monthly mean concentrations within the basin. Sites receiving runoff from the northern and northeastern parts of the Delaware River Basin had the largest monthly and annual mean atrazine concentrations. Time- weighted, annual mean atrazine concentrations did not exceed the MCL in water from any sampling site for either the 1993 or 1994 crop years (April-March); however, concentrations were during 1994 than during 1993. Time-weighted, annual mean concentrations in water from among the 11 sampling sites during the 1993 crop year ranged from 0.27 to 1.5 ug/L and from 0.36 to 2.8 ug/L during the 1994 crop year. Furthermore, concentrations in samples from the outflow of Perry Lake were larger during the first 6 months of the 1995 crop year than during the previous year. Flow-weighted, annual mean atrazine concentrations were larger than time-weighted, annual mean concentrations in water from all sampling sites upstream of Perry Lake, and samples from several sites had concentrations were substantially larger than the MCL. This difference explained why time-weighted, annual mean concentrations in the outflow of Perry Lake were larger than corresponding time-weighted concentrations in water from sampling sites upstream of Perry Lake. Flow- weighted, annual mean concentrations in water from among the 11 sampling sites during the 1993 crop year ranged from 1.0 to 4.4 ug/L and from 1.0 to 8.9 ug/L during the 1994 crop year. Statistically significant linear-regression equations were identified relating the percentage of subbasin in cropland to time- and flow-weighted, average annual mean atrazine concentrations. The relations indicate that time-weighted, average annual mean atrazine concentrations may not exceed the MCL in water from subbasins with at least about 70-percent cropland. However, flow-weighted, average annual mean atrazine concentrations may exceed the MCL when the percentage of cropland is greater than about 40 percent. Approximately 90 percent of the annual atrazine load is transport from May through July. Atrazine loads and yields were larger during the 1993 cro

Evaluation of the effects of Middleton's stormwater-management activities on streamflow and water-quality characteristics of Pheasant Branch, Dane County, Wisconsin 1975-2008

USGS Publications Warehouse

Gebert, Warren A.; Rose, William J.; Garn, Herbert S.

2012-01-01

Few long-term data sets are available for evaluating the effects of urban stormwater-management practices. Over 30 years of data are available for evaluating the effectiveness of such practices by the city of Middleton, Wis. Analysis of streamflow and water-quality data collected on Pheasant Branch, demonstrates the relation between the changes in the watershed to the structural and nonstructural best management practices put in place during 1975-2008. A comparison of the data from Pheasant Branch with streamflow and water-quality data (suspended sediment and total phosphorus) collected at other nearby streams was made to assist in the determination of the possible causes of the changes in Pheasant Branch. Based on 34 years of streamflow data collected at the Pheasant Branch at Middleton streamflow-gaging station, flood peak discharges increased 37 percent for the 2-year flood and 83 percent for the 100-year flood. A comparison of data for the same period from an adjacent rural stream, Black Earth at Black Earth had a 43 percent increase in the 2-year flood peak discharge and a 140-percent increase in the 100-year flood peak discharge. Because the flood peak discharges on Pheasant Branch have not increased as much as Black Earth Creek it appears that the stormwater management practices have been successful in mitigating the effects of urbanization. Generally urbanization results in increased flood peak discharges. The overall increase in flood peak discharges seen in both streams probably is the result of the substantial increase in precipitation during the study period. Average annual runoff in Pheasant Branch has also been increasing due to increasing average annual precipitation and urbanization. The stormwater-management practices in Middleton have been successful in decreasing the suspended-sediment and total phosphorus loads to Lake Mendota from the Pheasant Branch watershed. These loads decreased in spite of increased annual runoff and flood peaks, which are often expected to produce higher sediment and phosphorus loads. The biggest decreases in sediment and phosphorus loads occurred after 2001 when a large detention pond, the Confluence Pond, began operation. Since 2001, the annual suspended-sediment load has decreased from 2,650 tons per year to 1,450 tons per year for a 45-percent decrease. The annual total phosphorus load has decreased from 12,200 pounds per year to 6,300 pounds per year for a 48-percent decrease. A comparison of Pheasant Branch at Middleton with two other streams, Spring Harbor Storm Sewer and Yahara River at Windsor, that drain into Lake Mendota shows that suspended-sediment and total phosphorus load decreases were greatest at Pheasant Branch at Middleton. Prior to the construction of the Confluence Pond, annual suspended-sediment yield and total phosphorus yield from Pheasant Branch watershed was the largest of the three watersheds. After 2001, suspended-sediment yield was greatest at Spring Harbor Storm Sewer, and lowest at Yahara at Windsor; annual total phosphorus yield was greater at Yahara River at Windsor than that of Pheasant Branch. The stormwater-quality plan for Middleton shows that the city has met the present State of Wisconsin Administrative Code chap. NR216/NR151 requirements of reducing total suspended solids by 20 percent for the developed area in Middleton. In addition, the city already has met the 40-percent reduction in total suspended solids required by 2013. Snow and ice melt runoff from road surfaces and parking lots following winter storms can effect water quality because the runoff contains varying amounts of road salt. To evaluate the effect of road deicing on stream water quality in Pheasant Branch, specific conductance and chloride were monitored during two winter seasons. The maximum estimated concentration of chloride during the monitoring period was 931 milligrams per liter, which exceeded the U.S. Environmental Protection Agency acute criterion of 860 milligrams per liter. Chloride concentrations exceeded the U.S. Environmental Protection Agency chronic criterion of 230 milligrams per liter for at least 10 days during February and March 2007 and for 45 days during the 2007-8 winter seasons. The total sodium chloride load for the monitoring period was 1,720 tons and the largest sodium chloride load occurred in March and April of each year.

Total Phosphorus Loads for Selected Tributaries to Sebago Lake, Maine

USGS Publications Warehouse

Hodgkins, Glenn A.

2001-01-01

The streamflow and water-quality datacollection networks of the Portland Water District (PWD) and the U.S. Geological Survey (USGS) as of February 2000 were analyzed in terms of their applicability for estimating total phosphorus loads for selected tributaries to Sebago Lake in southern Maine. The long-term unit-area mean annual flows for the Songo River and for small, ungaged tributaries are similar to the long-term unit-area mean annual flows for the Crooked River and other gaged tributaries to Sebago Lake, based on a regression equation that estimates mean annual streamflows in Maine. Unit-area peak streamflows of Sebago Lake tributaries can be quite different, based on a regression equation that estimates peak streamflows for Maine. Crooked River had a statistically significant positive relation (Kendall's Tau test, p=0.0004) between streamflow and total phosphorus concentration. Panther Run had a statistically significant negative relation (p=0.0015). Significant positive relations may indicate contributions from nonpoint sources or sediment resuspension, whereas significant negative relations may indicate dilution of point sources. Total phosphorus concentrations were significantly larger in the Crooked River than in the Songo River (Wilcoxon rank-sum test, p<0.0001). Evidence was insufficient, however, to indicate that phosphorus concentrations from medium-sized drainage basins, at a significance level of 0.05, were different from each other or that concentrations in small-sized drainage basins were different from each other (Kruskal-Wallis test, p= 0.0980, 0.1265). All large- and medium-sized drainage basins were sampled for total phosphorus approximately monthly. Although not all small drainage basins were sampled, they may be well represented by the small drainage basins that were sampled. If the tributaries gaged by PWD had adequate streamflow data, the current PWD tributary monitoring program would probably produce total phosphorus loading data that would represent all gaged and ungaged tributaries to Sebago Lake. Outside the PWD tributary-monitoring program, the largest ungaged tributary to Sebago Lake contains 1.5 percent of the area draining to the lake. In the absence of unique point or nonpoint sources of phosphorus, ungaged tributaries are unlikely to have total phosphorus concentrations that differ significantly from those in the small tributaries that have concentration data. The regression method, also known as the rating-curve method, was used to estimate the annual total phosphorus load for Crooked River, Northwest River, and Rich Mill Pond Outlet for water years 1996-98. The MOVE.1 method was used to estimate daily streamflows for the regression method at Northwest River and Rich Mill Pond Outlet, where streamflows were not continuously monitored. An averaging method also was used to compute annual loads at the three sites. The difference between the regression estimate and the averaging estimate for each of the three tributaries was consistent with what was expected from previous studies.

Changes in bottom-surface elevations in three reservoirs on the lower Susquehanna River, Pennsylvania and Maryland, following the January 1996 flood; implications for nutrient and sediment loads to Chesapeake Bay

USGS Publications Warehouse

Langland, Michael J.; Hainly, Robert A.

1997-01-01

The Susquehanna River drains about 27,510 square miles in New York, Pennsylvania, and Maryland, contributes nearly 50 percent of the freshwater discharge to the Chesapeake Bay, and contributes nearly 66 percent of the annual nitrogen load, 40 percent of the phosphorus load, and 25 percent of the suspended-sediment load from non-tidal parts of the Bay during a year of average streamflow. A reservoir system formed by three hydroelectric dams on the lower Susquehanna River is currently trapping a major part of the phosphorus and suspended-sediment loads from the basin and, to a lesser extent, the nitrogen loads.In the summer of 1996, the U. S. Geological Survey collected bathymetric data along 64 cross sections and 40 bottom-sediment samples along 14 selected cross sections in the lower Susquehanna River reservoir system to determine the remaining sediment-storage capacity, refine the current estimate of when the system may reach sediment-storage capacity, document changes in the reservoir system after the January 1996 flood, and determine the remaining nutrient mass in Conowingo Reservoir. Results from the 1996 survey indicate an estimated total of 14,800,000 tons of sediment were scoured from the reservoir system from 1993 (date of previous bathymetric survey) through 1996. This includes the net sediment change of 4,700,000 tons based on volume change in the reservoir system computed from the 1993 and 1996 surveys, the 6,900,000 tons of sediment deposited from 1993 through 1996, and the 3,200,000 tons of sediment transported into the reservoir system during the January 1996 flood. The January 1996 flood, which exceeded a 100-year recurrence interval, scoured about the same amount of sediment that normally would be deposited in the reservoir system during a 4- to 6-year period.Concentrations of total nitrogen in bottom sediments in the Conowingo Reservoir ranged from 1,500 to 6,900 mg/kg (milligrams per kilogram); 75 percent of the concentrations were between 3,000 and 5,000 mg/kg. About 96 percent of the concentrations of total nitrogen consisted of organic nitrogen. Concentrations of total phosphorus in bottom sediments ranged from 286 to 1,390 mg/kg. About 84 percent of the concentrations of total phosphorus were comprised of inorganic phosphorus. The ratio of concentrations of plant-available phosphorus to concentrations of total phosphorus ranged from 0.6 to 3.5 percent; ratios generally decreased in a downstream direction.About 29,000 acre-feet, or 42,000,000 tons, of sediment can be deposited before Conowingo Reservoir reaches sediment-storage capacity. Assuming the average annual sediment-deposition rate remains unchanged and no scour occurs due to floods, the reservoir system could reach sediment-storage capacity in about 17 years. The reservoir system currently is trapping about 2 percent of the nitrogen, 45 percent of the phosphorus, and 70 percent of the suspended sediment transported by the river to the upper Chesapeake Bay. Once the reservoir reaches sediment-storage capacity, an estimated 250-percent increase in the current annual loads of suspended sediment, a 2-percent increase in the current annual loads of total nitrogen, and a 70-percent increase in the current annual loads of total phosphorus from the Susquehanna River to Chesapeake Bay can be expected. If the goal of a 40-percent reduction in controllable phosphorus load from the Susquehanna River Basin is met before the reservoirs reach sediment-storage capacity, the 40-percent reduction goal will probably be exceeded when the reservoir system reaches sediment-storage capacity.

Estimates of Sediment Load Prior to Dam Removal in the Elwha River, Clallam County, Washington

USGS Publications Warehouse

Curran, Christopher A.; Konrad, Christopher P.; Higgins, Johnna L.; Bryant, Mark K.

2009-01-01

Years after the removal of the two dams on the Elwha River, the geomorphology and habitat of the lower river will be substantially influenced by the sediment load of the free-flowing river. To estimate the suspended-sediment load prior to removal of the dams, the U.S. Geological Survey collected suspended-sediment samples during water years 2006 and 2007 at streamflow-gaging stations on the Elwha River upstream of Lake Mills and downstream of Glines Canyon Dam at McDonald Bridge. At the gaging station upstream of Lake Mills, discrete samples of suspended sediment were collected over a range of streamflows including a large peak in November 2006 when suspended-sediment concentrations exceeded 7,000 milligrams per liter, the highest concentrations recorded on the river. Based on field measurements in this study and from previous years, regression equations were developed for estimating suspended-sediment and bedload discharge as a function of streamflow. Using a flow duration approach, the average total annual sediment load at the gaging station upstream of Lake Mills was estimated at 327,000 megagrams with a range of uncertainty of +57 to -34 percent (217,000-513,000 megagrams) at the 95 percent confidence level; 77 percent of the total was suspended-sediment load and 23 percent was bedload. At the McDonald Bridge gaging station, daily suspended-sediment samples were obtained using an automated pump sampler, and concentrations were combined with the record of streamflow to calculate daily, monthly, and annual suspended-sediment loads. In water year 2006, an annual suspended-sediment load of 49,300 megagrams was determined at the gaging station at McDonald Bridge, and a load of 186,000 megagrams was determined upstream at the gaging station upstream of Lake Mills. In water year 2007, the suspended-sediment load was 75,200 megagrams at McDonald Bridge and 233,000 megagrams upstream of Lake Mills. The large difference between suspended-sediment loads at both gaging stations shows the extent of sediment trapping by Lake Mills, and a trap efficiency of 0.86 was determined for the reservoir. Pre-dam-removal estimates of suspended-sediment load and sediment-discharge relations will help planners monitor geomorphic and habitat changes in the river as it reaches a dynamic equilibrium following the removal of dams.

Water quality of the West Branch Lackawaxen River and limnology of Prompton Lake, Wayne County, Pennsylvania, October 1986 through September 1987

USGS Publications Warehouse

Barker, J.L.

1989-01-01

The water quality of the West Branch Lackawaxen River and the limnology of Prompton Lake in northeastern Pennsylvania were studied from October 1986 through September 1987 to determine past and present water-quality conditions in the basin, and to determine the possible effects of raising the lake level on the water quality of the Lake, of the river downstream, and of ground water. Past and present water quality of the West Branch Lackawaxen River and Prompton Lake generally meets State standards for high-quality waters that sup- port the maintenance and propagation of cold-water fishes. However, suggested criteria by the U.S. Environmental Protection Agency intended to control excessive algal growth in the lake are exceeded most, if not all, of the time for nitrogen and most of the time for phosphorus. The average annual total nitrogen load entering the lake is 114 tons. Of this total, 41 tons is inorganic nitrate plus nitrate, 48 tons organic nitrogen, and 25 tons ammonia nitrogen. Estimated annual yields of total nitrogen, inorganic nitrite plus nitrate, organic nitrogen, and ammonia nitrogen are 1.9, 9.7, 0.8, and 0.4 tons/mi2 (tons per square mile), respectively. The average annual phosphorus load is estimated to be 4.7 tons, which is equivalent to a yield of 0.08 tons/mi2. About 62 percent, or 2.9 tons, is dissolved phosphorus that is readily available for plant assimilation. The waters of the West Branch Lackawaxen River and Prompton Lake are decidedly phosphorus limited. The long-term average annual suspended-sediment yield to the lake is about 70 tons/mi2. Life expectancy of the 774 acre-feet of space allocated for sediment loads in the raised pool is estimated to be about 287 years. During the 1987 water year, about 51 percent of the annual sediment load was transported during 7 days by storm-water runoff. The maximum sediment discharge during the study period was 400 tons per day. Lake-profile studies show that thermal and chemical stratification develops in early June and persists through September. Water below a depth of about 20 feet becomes anoxic, or nearly so, by mid-July. Summer concentrations of chlorophyll are indicative of eutropic conditions. Although raising of the lake level is expected to increase the efficiency of the lake in trapping nutrients, the increased depth and volume will reduce the concentrations of available nutrients and, thereby, reduce the eutrophication potential of the lake. The water level in about 30 wells near the lake probably will rise after the lake level is raised, and the well yields probably will increase slightly. Flow of water form the lake to the aquifer as the lake is being raised may temporarily increase mineral content of water in the aquifer. After a new equilibrium is reached, however, water will again flow from the aquifer to the lake, thereby restoring the aquifer's water quality.

Modelling the regulation effects of lowland polder with pumping station on hydrological processes and phosphorus loads.

PubMed

Yan, Renhua; Li, Lingling; Gao, Junfeng

2018-05-08

Exploring the hydrological regulation of a lowland polder is essential for increasing knowledge regarding the role of polders associated with pumping stations in lowlands. In this study, the Lowland Polder Hydrology and Phosphorus modelling System (PHPS) was applied to the Jianwei polder as a case study for quantifying the regulation effects of a lowland polder with pumping on discharge and phosphorus loads. The results indicate that the polder significantly affected the temporal distribution and annual amount of catchment discharge. Compared with a no-pumping scenario, an agricultural polder with pumping stations generated a sharper discharge hydrograph with higher peak-values and lower minimum-values, as well as an 8.6% reduction in average annual discharge. It also decreased the phosphorus export to downstream water bodies by 5.33 kg/hm 2 /yr because of widespread ditches and ponds, a lower hydraulic gradient, and increased retention times of surface water in ponds. Copyright © 2018 Elsevier B.V. All rights reserved.

Response of Colorado River runoff to dust radiative forcing in snow.

PubMed

Painter, Thomas H; Deems, Jeffrey S; Belnap, Jayne; Hamlet, Alan F; Landry, Christopher C; Udall, Bradley

2010-10-05

The waters of the Colorado River serve 27 million people in seven states and two countries but are overallocated by more than 10% of the river's historical mean. Climate models project runoff losses of 7-20% from the basin in this century due to human-induced climate change. Recent work has shown however that by the late 1800s, decades prior to allocation of the river's runoff in the 1920s, a fivefold increase in dust loading from anthropogenically disturbed soils in the southwest United States was already decreasing snow albedo and shortening the duration of snow cover by several weeks. The degree to which this increase in radiative forcing by dust in snow has affected timing and magnitude of runoff from the Upper Colorado River Basin (UCRB) is unknown. Here we use the Variable Infiltration Capacity model with postdisturbance and predisturbance impacts of dust on albedo to estimate the impact on runoff from the UCRB across 1916-2003. We find that peak runoff at Lees Ferry, Arizona has occurred on average 3 wk earlier under heavier dust loading and that increases in evapotranspiration from earlier exposure of vegetation and soils decreases annual runoff by more than 1.0 billion cubic meters or ∼5% of the annual average. The potential to reduce dust loading through surface stabilization in the deserts and restore more persistent snow cover, slow runoff, and increase water resources in the UCRB may represent an important mitigation opportunity to reduce system management tensions and regional impacts of climate change.

Response of Colorado River runoff to dust radiative forcing in snow

PubMed Central

Painter, Thomas H.; Deems, Jeffrey S.; Belnap, Jayne; Hamlet, Alan F.; Landry, Christopher C.; Udall, Bradley

2010-01-01

The waters of the Colorado River serve 27 million people in seven states and two countries but are overallocated by more than 10% of the river’s historical mean. Climate models project runoff losses of 7–20% from the basin in this century due to human-induced climate change. Recent work has shown however that by the late 1800s, decades prior to allocation of the river’s runoff in the 1920s, a fivefold increase in dust loading from anthropogenically disturbed soils in the southwest United States was already decreasing snow albedo and shortening the duration of snow cover by several weeks. The degree to which this increase in radiative forcing by dust in snow has affected timing and magnitude of runoff from the Upper Colorado River Basin (UCRB) is unknown. Here we use the Variable Infiltration Capacity model with postdisturbance and predisturbance impacts of dust on albedo to estimate the impact on runoff from the UCRB across 1916–2003. We find that peak runoff at Lees Ferry, Arizona has occurred on average 3 wk earlier under heavier dust loading and that increases in evapotranspiration from earlier exposure of vegetation and soils decreases annual runoff by more than 1.0 billion cubic meters or ∼5% of the annual average. The potential to reduce dust loading through surface stabilization in the deserts and restore more persistent snow cover, slow runoff, and increase water resources in the UCRB may represent an important mitigation opportunity to reduce system management tensions and regional impacts of climate change. PMID:20855581

Modelling and Evaluation of Environmental Impact due to Continuous Emissions of the Severonickel Plant (Kola Peninsula)

NASA Astrophysics Data System (ADS)

Mahura, A.; Gonzalez-Aparicio, I.; Nuterman, R.; Baklanov, A.

2012-04-01

In this study, evaluation of potential impact - through concentration, deposition and loadings patterns - on population and environment due to continuous anthropogenic emissions (on example of sulfates) of the Cu-Ni smelters of the Russian North is given. To estimate impact, the Danish Emergency Response Model for Atmosphere (DERMA) was employed to perform long-term simulations of air concentration, time integrated air concentration (TIAC), dry (DD) and wet (WD) deposition patterns resulting from continuous emissions of the Severonickel smelters located on the Kola Peninsula (Murmansk region, Russia). To perform such simulations the 3D meteorological fields (from the European Center for Medium-Range Weather Forecasts, ECMWF) for the year 2000 were used as input. For simplicity, it has been assumed that normalized releases of sulfates from smelters location occurred at a constant rate every day. For each daily release the atmospheric transport, dispersion, dry and wet deposition due to removal processes were estimated during 10 day interval. Output from these long-term simulations is an essential input for evaluation of impact, doses, risks, and short- and long-term consequences, etc. Detailed analyses of simulated concentration and deposition fields allowed evaluating the spatial and temporal variability of resulted patterns on different scales. Temporal variability of both wet and dry deposition as well as their contribution into total deposition have been estimated. On an annual scale, the concentration and deposition patterns were estimated for the most populated cities of the North-West Russia. The modeled annual fields were also integrated into GIS environment as well as layers with population density (from the Center for International Earth Science Information Network, CIESIN) and standard administrative division of the North-West Russia and bordering countries. Furthermore, the estimation of deposited amounts (loadings) of sulfates for selected regions of Russia and border countries has been performed. It has been found that for the "mild emission scenario" (i.e. approx. 31.6 ths. ton), for the Severonickel smelters, the annual average daily dry deposition value is 5.79 ton (with the highest - 10.4 ton - in September, and the lowest - 2.9 ton - in March). The annual average daily wet deposition is 22.7 tons, and a strong month-to-month variability is seen compared with dry deposition. The highest average WD (46.3 ton) is in January, and the lowest - 5.5 ton - in July. There are also differences in amount deposited in total from daily releases. On an annual scale, on average, 32.9% of emitted amount could be deposited at the surface during the considered duration (i.e. 10 days) of atmospheric transport. The highest deposited amount of 57.2% is observed in January and the lowest of 14.3% - in July. Taking into account actual annual (on example of year 2000) emissions of sulfur dioxide as 45.3 ths. ton (Severonickel smelters, city of Monchegorsk), the summary annual time integrated air concentration, dry and wet deposition were re-scaled and these have been estimated for most populated cities (Arkhangelsk, Petrozavodsk, Sankt-Petersburg, Syktyvkar, Pskov, and Vologda) of the North-West Russia. It was found that among these cities, the TIAC is the highest - 86 μg•h/m3 - for Arkhangelsk and the lowest - 4 μg•h/m3 - for Pskov. Both dry and wet depositions were also the highest for Arkhangelsk - 0.5 and 2.2 mg/m2, respectively. Detailed analysis also showed that for regions surrounding the Kola Peninsula, on average (maximum), the total (dry plus wet) deposition was 0.6 (3.0), 1.8 (5.1), and 28.3 (122) mg/m2 for the territories of the Arkhangelsk, Karelia, and Murmansk regions of Russia. For border regions with Scandinavian countries, on average (maximum), the total deposition was 2.2 (6.7) mg/m2 in Finnmark (Norway); 0.2 (0.4) in Norrbotten and 0.03 (0.1) mg/m2 in Vsterbotten counties (Sweden); 0.6 (1.2) in Eastern Finland, 2.2 (7.2) in Lapland, and 1.4 (2.9) mg/m2 in Oulu provinces of Finland. For urban population living in the central and northern territories of the Kola Peninsula the yearly loading due to deposition of sulfates could be more than 40 kg/person. For bordering territories with the Murmansk region such loadings are less than 5 kg/person for the Eastern Finland, Karelia, and Arkhangelsk regions; and up to 15 kg/person - for the Northern Norway.

Occurrence and load of selected herbicides and metabolites in the lower Mississippi River

USGS Publications Warehouse

Clark, G.M.; Goolsby, D.A.

2000-01-01

Analyses of water samples collected from the Mississippi River at Baton Rouge, Louisiana, during 1991-1997 indicate that hundreds of metric tons of herbicides and herbicide metabolites are being discharged annually to the Gulf of Mexico. Atrazine, metolachlor, and the ethane-sulfonic acid metabolite of alachlor (alachlor ESA) were the most frequently detected herbicides and, in general, were present in the largest concentrations. Almost 80% of the annual herbicide load to the Gulf of Mexico occurred during the growing season from May to August. The concentrations and loads of alachlor in the Mississippi River decreased dramatically after 1993 in response to decreased use in the basin. In contrast, the concentrations and loads of acetochlor increased after 1994, reflecting its role as a replacement for alachlor. The peak annual herbicide load occurred in 1993, when approximately 640 metric tons (t) of atrazine, 320 t of cyanazine, 215 t of metolachlor, 53 t of simazine, and 50 t of alachlor were discharged to the Gulf of Mexico. The annual loads of atrazine and cyanazine were generally 1-2% of the amount annually applied in the Mississippi River drainage basin; the annual loads of acetochlor, alachlor, and metolachlor were generally less than 1%. Despite a reduction in atrazine use, historical data do not indicate a long-term downward trend in the atrazine load to the Gulf of Mexico. Although a relation (r2=0.62) exists between the atrazine load and stream discharge during May to August, variations in herbicide use and rainfall patterns within subbasins can have a large effect on herbicide loads in the Mississippi River Basin and probably explain a large part of the annual variation in atrazine load to the Gulf of Mexico. Copyright (C) 2000 Elsevier Science B.V.

Occurrence and load of selected herbicides and metabolites in the lower Mississippi River

USGS Publications Warehouse

Clark, Gregory M.; Goolsby, Donald A.

2000-01-01

Analyses of water samples collected from the Mississippi River at Baton Rouge, Louisiana, during 1991–1997 indicate that hundreds of metric tons of herbicides and herbicide metabolites are being discharged annually to the Gulf of Mexico. Atrazine, metolachlor, and the ethane-sulfonic acid metabolite of alachlor (alachlor ESA) were the most frequently detected herbicides and, in general, were present in the largest concentrations. Almost 80% of the annual herbicide load to the Gulf of Mexico occurred during the growing season from May to August. The concentrations and loads of alachlor in the Mississippi River decreased dramatically after 1993 in response to decreased use in the basin. In contrast, the concentrations and loads of acetochlor increased after 1994, reflecting its role as a replacement for alachlor. The peak annual herbicide load occurred in 1993, when approximately 640 metric tons (t) of atrazine, 320 t of cyanazine, 215 t of metolachlor, 53 t of simazine, and 50 t of alachlor were discharged to the Gulf of Mexico. The annual loads of atrazine and cyanazine were generally 1–2% of the amount annually applied in the Mississippi River drainage basin; the annual loads of acetochlor, alachlor, and metolachlor were generally less than 1%. Despite a reduction in atrazine use, historical data do not indicate a long-term downward trend in the atrazine load to the Gulf of Mexico. Although a relation (r2=0.62) exists between the atrazine load and stream discharge during May to August, variations in herbicide use and rainfall patterns within subbasins can have a large effect on herbicide loads in the Mississippi River Basin and probably explain a large part of the annual variation in atrazine load to the Gulf of Mexico.

Occurrence of Organic Compounds and Trace Elements in the Upper Passaic and Elizabeth Rivers and Their Tributaries in New Jersey, July 2003 to February 2004: Phase II of the New Jersey Toxics Reduction Workplan for New York-New Jersey Harbor

USGS Publications Warehouse

Wilson, Timothy P.; Bonin, Jennifer L.

2008-01-01

Samples of surface water and suspended sediment were collected from the Passaic and Elizabeth Rivers and their tributaries in New Jersey from July 2003 to February 2004 to determine the concentrations of selected chlorinated organic and inorganic constituents. This sampling and analysis was conducted as Phase II of the New York-New Jersey Harbor Estuary Workplan?Contaminant Assessment and Reduction Program (CARP), which is overseen by the New Jersey Department of Environmental Protection. Phase II of the New Jersey Workplan was conducted to define upstream tributary and point sources of contaminants in those rivers sampled during Phase I work, with special emphasis on the Passaic and Elizabeth Rivers. Samples were collected from three groups of tributaries: (1) the Second, Third, and Saddle Rivers; (2) the Pompton and upper Passaic Rivers; and (3) the West Branch and main stem of the Elizabeth River. The Second, Third, and Saddle Rivers were sampled near their confluence with the tidal Passaic River, but at locations not affected by tidal flooding. The Pompton and upper Passaic Rivers were sampled immediately upstream from their confluence at Two Bridges, N.J. The West Branch and the main stem of the Elizabeth River were sampled just upstream from their confluence at Hillside, N.J. All tributaries were sampled during low-flow discharge conditions using the protocols and analytical methods for organic constituents used in low-flow sampling in Phase I. Grab samples of streamflow also were collected at each site and were analyzed for trace elements (mercury, methylmercury, cadmium, and lead) and for suspended sediment, particulate organic carbon, and dissolved organic carbon. The measured concentrations and available historical suspended-sediment and stream-discharge data (where available) were used to estimate average annual loads of suspended sediment and organic compounds in these rivers. Total suspended-sediment loads for 1975?2000 were estimated using rating curves developed from historical U.S. Geological Survey (USGS) suspended-sediment and discharge data, where available. Average annual loads of suspended sediment, in millions of kilograms per year (Mkg/yr), were estimated to be 0.190 for the Second River, 0.23 for the Third River, 1.00 for the Saddle River, 1.76 for the Pompton River, and 7.40 for the upper Passaic River. On the basis of the available discharge records, the upper Passaic River was estimated to provide approximately 60 percent of the water and 80 percent of the total suspended-sediment load at the Passaic River head-of-tide, whereas the Pompton River provided roughly 20 percent of the total suspended-sediment load estimated at the head-of-tide. The combined suspended-sediment loads of the upper Passaic and Pompton Rivers (9.2 Mkg/yr), however, represent only 40 percent of the average annual suspended-sediment load estimated for the head-of-tide (23 Mkg/yr) at Little Falls, N.J. The difference between the combined suspended-sediment loads of the tributaries and the estimated load at Little Falls represents either sediment trapped upriver from the dam at Little Falls, additional inputs of suspended sediment downstream from the tributary confluence, or uncertainty in the suspended-sediment and discharge data that were used. The concentrations of total suspended sediment-bound polychlorinated biphenyls (PCBs) in the tributaries to the Passaic River were 194 ng/g (nanograms per gram) in the Second River, 575 ng/g in the Third River, 2,320 ng/g in the Saddle River, 200 ng/g in the Pompton River, and 87 ng/g in the upper Passic River. The dissolved PCB concentrations in the tributaries were 563 pg/L (picograms per liter) in the Second River, 2,510 pg/L in the Third River, 2,270 pg/L in the Saddle River, 887 pg/L in the Pompton River, and 1,000 pg/L in the upper Passaic River. Combined with the sediment loads and discharge, these concentrations resulted in annual loads of suspended sediment-bound PCBs, i

Sources of metal loads to the Alamosa River and estimation of seasonal and annual metal loads for the Alamosa River basin, Colorado, 1995-97

USGS Publications Warehouse

Ortiz, Roderick F.; Edelmann, Patrick; Ferguson, Sheryl; Stogner, Robert

2002-01-01

Metal contamination in the upper Alamosa River Basin has occurred for decades from the Summitville Mine site, from other smaller mines, and from natural, metal-enriched acidic drainage in the basin. In 1995, the need to quantify contamination from various source areas in the basin and to quantify the spatial, seasonal, and annual metal loads in the basin was identified. Data collection occurred from 1995 through 1997 at numerous sites to address data gaps. Metal loads were calculated and the percentages of metal load contributions from tributaries to three risk exposure areas were determined. Additionally, a modified time-interval method was used to estimate seasonal and annual metal loads in the Alamosa River and Wightman Fork. Sources of dissolved and total-recoverable aluminum, copper, iron, and zinc loads were determined for Exposure Areas 3a, 3b, and 3c. Alum Creek is the predominant contributor of aluminum, copper, iron, and zinc loads to Exposure Area 3a. In general, Wightman Fork was the predominant source of metals to Exposure Area 3b, particularly during the snowmelt and summer-flow periods. During the base-flow period, however, aluminum and iron loads from Exposure Area 3a were the dominant source of these metals to Exposure Area 3b. Jasper and Burnt Creeks generally contributed less than 10 percent of the metal loads to Exposure Area 3b. On a few occasions, however, Jasper and Burnt Creeks contributed a substantial percentage of the loads to the Alamosa River. The metal loads calculated for Exposure Area 3c result from upstream sources; the primary upstream sources are Wightman Fork, Alum Creek, and Iron Creek. Tributaries in Exposure Area 3c did not contribute substantially to the metal load in the Alamosa River. In many instances, the percentage of dissolved and/or total-recoverable metal load contribution from a tributary or the combined percentage of metal load contribution was greater than 100 percent of the metal load at the nearest downstream site on the Alamosa River. These data indicate that metal partitioning and metal deposition from the water column to the streambed may be occurring in Exposure Areas 3a, 3b, and 3c. Metals that are deposited to the streambed probably are resuspended and transported downstream during high streamflow periods such as during snowmelt runoff and rainfall runoff. Seasonal and annual dissolved and totalrecoverable aluminum, copper, iron, and zinc loads> for 1995?97 were estimated for Exposure Areas 1, 2, 3a, 3b, and 3c. During 1995?97, many tons of metals were transported annually through each exposure area. Generally, the largest estimated annual totalrecoverable metal mass for most metals was in 1995. The smallest estimated annual total-recoverable metal mass was in 1996, which also had the smallest annual streamflow. In 1995 and 1997, more than 60 percent of the annual total-recoverable metal loads generally was transported through each exposure area during the snowmelt period. A comparison of the estimated storm load at each site to the corresponding annual load indicated that storms contribute less than 2 percent of the annual load at any site and about 5 to 20 percent of the load during the summer-flow period.

Atmospheric deposition and riverine load of (90)Sr and (137)Cs to the Gulf of Gdańsk (southern Baltic Sea) in the period 2005-2011.

PubMed

Saniewski, Michał; Zalewska, Tamara

2016-01-01

In the period 2005-2011 total atmospheric fallout and the riverine input to the Gulf of Gdańsk was 1168.8 GBq of (90)Sr and 424.1 GBq (137)Cs. The major source of both radionuclides to the Gulf of Gdańsk is the Vistula river; its contribution reached 99.7% in the case of (90)Sr and 95.8% regarding (137)Cs. The atmospheric load of (137)Cs, 18.1 GBq, was nearly 4 times bigger than in the case of (90)Sr (3.75 GBq). In the period 2005-2010, the average annual atmospheric load were at the levels 2-3 GBq for (137)Cs and 0.4-0.6 GBq for (90)Sr, while in 2011, due to the Fukuchima Dai-ichi power plant break down, an increase of annual atmospheric loads was noted to 5.3 GBq of (137)Cs and to 0.87 GBq of (90)Sr. The additional loads did not have an increasing effect on the activity concentrations of (137)Cs and (90)Sr in seawater of the Gulf of Gdańsk, where mean activity concentrations in seawater were equal to 31.1 Bq m(-3) and 7.6 Bq m(-3) in the case of (137)Cs and (90)Sr respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nutrient and sediment concentrations and corresponding loads during the historic June 2008 flooding in eastern Iowa

USGS Publications Warehouse

Hubbard, L.; Kolpin, D.W.; Kalkhoff, S.J.; Robertson, Dale M.

2011-01-01

A combination of above-normal precipitation during the winter and spring of 2007-2008 and extensive rainfall during June 2008 led to severe flooding in many parts of the midwestern United States. This resulted in transport of substantial amounts of nutrients and sediment from Iowa basins into the Mississippi River. Water samples were collected from 31 sites on six large Iowa tributaries to the Mississippi River to characterize water quality and to quantify nutrient and sediment loads during this extreme discharge event. Each sample was analyzed for total nitrogen, dissolved nitrate plus nitrite nitrogen, dissolved ammonia as nitrogen, total phosphorus, orthophosphate, and suspended sediment. Concentrations measured near peak flow in June 2008 were compared with the corresponding mean concentrations from June 1979 to 2007 using a paired t test. While there was no consistent pattern in concentrations between historical samples and those from the 2008 flood, increased flow during the flood resulted in near-peak June 2008 flood daily loads that were statistically greater (p < 0.05) than the median June 1979 to 2007 daily loads for all constituents. Estimates of loads for the 16-d period during the flood were calculated for four major tributaries and totaled 4.95 x 10(7) kg of nitrogen (N) and 2.9 x 10(6) kg of phosphorus (P) leaving Iowa, which accounted for about 22 and 46% of the total average annual nutrient yield, respectively. This study demonstrates the importance of large flood events to the total annual nutrient load in both small streams and large rivers.

Nutrient and sediment concentrations and corresponding loads during the historic June 2008 flooding in eastern Iowa.

PubMed

Hubbard, L; Kolpin, D W; Kalkhoff, S J; Robertson, D M

2011-01-01

A combination of above-normal precipitation during the winter and spring of 2007-2008 and extensive rainfall during June 2008 led to severe flooding in many parts of the midwestern United States. This resulted in transport of substantial amounts of nutrients and sediment from Iowa basins into the Mississippi River. Water samples were collected from 31 sites on six large Iowa tributaries to the Mississippi River to characterize water quality and to quantify nutrient and sediment loads during this extreme discharge event. Each sample was analyzed for total nitrogen, dissolved nitrate plus nitrite nitrogen, dissolved ammonia as nitrogen, total phosphorus, orthophosphate, and suspended sediment. Concentrations measured near peak flow in June 2008 were compared with the corresponding mean concentrations from June 1979 to 2007 using a paired t test. While there was no consistent pattern in concentrations between historical samples and those from the 2008 flood, increased flow during the flood resulted in near-peak June 2008 flood daily loads that were statistically greater (p < 0.05) than the median June 1979 to 2007 daily loads for all constituents. Estimates of loads for the 16-d period during the flood were calculated for four major tributaries and totaled 4.95 x 10(7) kg of nitrogen (N) and 2.9 x 10(6) kg of phosphorus (P) leaving Iowa, which accounted for about 22 and 46% of the total average annual nutrient yield, respectively. This study demonstrates the importance of large flood events to the total annual nutrient load in both small streams and large rivers.

Updated estimates of long-term average dissolved-solids loading in streams and rivers of the Upper Colorado River Basin

USGS Publications Warehouse

Tillman, Fred D.; Anning, David W.

2014-01-01

The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating over 4.5 million acres of farmland, and annually generating about 12 billion kilowatt hours of hydroelectric power. The Upper Colorado River Basin, part of the Colorado River Basin, encompasses more than 110,000 mi2 and is the source of much of more than 9 million tons of dissolved solids that annually flows past the Hoover Dam. High dissolved-solids concentrations in the river are the cause of substantial economic damages to users, primarily in reduced agricultural crop yields and corrosion, with damages estimated to be greater than 300 million dollars annually. In 1974, the Colorado River Basin Salinity Control Act created the Colorado River Basin Salinity Control Program to investigate and implement a broad range of salinity control measures. A 2009 study by the U.S. Geological Survey, supported by the Salinity Control Program, used the Spatially Referenced Regressions on Watershed Attributes surface-water quality model to examine dissolved-solids supply and transport within the Upper Colorado River Basin. Dissolved-solids loads developed for 218 monitoring sites were used to calibrate the 2009 Upper Colorado River Basin Spatially Referenced Regressions on Watershed Attributes dissolved-solids model. This study updates and develops new dissolved-solids loading estimates for 323 Upper Colorado River Basin monitoring sites using streamflow and dissolved-solids concentration data through 2012, to support a planned Spatially Referenced Regressions on Watershed Attributes modeling effort that will investigate the contributions to dissolved-solids loads from irrigation and rangeland practices.

Evaluation and use of U.S. Environmental Protection Agency Clean Watersheds Needs Survey data to quantify nutrient loads to surface water, 1978–2012

USGS Publications Warehouse

Ivahnenko, Tamara I.

2017-12-07

Changes in municipal and industrial point-source discharges over time have been an important factor affecting nutrient trends in many of the Nation’s streams and rivers. This report documents how three U.S. Environmental Protection Agency (EPA) national datasets—the Permit Compliance System, the Integrated Compliance Information System, and the Clean Watersheds Needs Survey—were evaluated for use in the U.S. Geological Survey National Water-Quality Assessment project to assess the causes of nutrient trends. This report also describes how a database of total nitrogen load and total phosphorous load was generated for select wastewater treatment facilities in the United States based on information reported in the EPA Clean Watersheds Needs Survey. Nutrient loads were calculated for the years 1978, 1980, 1982, 1984, 1986, 1988, 1990, 1992, 1996, 2000, 2004, 2008, and 2012 based on average nitrogen and phosphorous concentrations for reported treatment levels and on annual reported flow values.The EPA Permit Compliance System (PCS) and Integrated Compliance Information System (ICIS), which monitor point-source facility discharges, together are the Nation’s most spatially comprehensive dataset for nutrients released to surface waters. However, datasets for many individual facilities are incomplete, the PCS/ICIS historical data date back only to 1989, and historical data are available for only a limited number of facilities. Additionally, inconsistencies in facility reporting make it difficult to track or identify changes in nutrient discharges over time. Previous efforts made by the U.S. Geological Survey to “fill in” gaps in the PCS/ICIS data were based on statistical methods—missing data were filled in through the use of a statistical model based on the Standard Industrial Classification code, size, and flow class of the facility and on seasonal nutrient discharges of similar facilities. This approach was used to estimate point-source loads for a single point in time; it was not evaluated for use in generating a consistent data series over time.Another national EPA dataset that is available is the Clean Watersheds Needs Survey (CWNS), conducted every 4 years beginning 1973. The CWNS is an assessment of the capital needs of wastewater facilities to meet the water-quality goals set in the Clean Water Act. Data collected about these facilities include location and contact information for the facilities; population served; flow and treatment level of the facility; estimated capital needs to upgrade, repair, or improve facilities for water quality; and nonpoint-source best management practices.Total nitrogen and total phosphorous load calculations for each of the CWNS years were based on treatment level information and average annual outflow (in million gallons per day) from each of the facilities that had reported it. Treatment levels categories (such as Primary, Secondary, or Advanced) were substituted with average total nitrogen and total phosphorous concentrations for each treatment level based on those reported in literature. The CWNS dataset, like the PCS/ICIS dataset, has years where facilities did not report either a treatment level or an annual average outflow, or both. To fill in the data gaps, simple linear assumptions were made based on each facility’s responses to the survey in years bracketing the data gap or immediately before or after the data gap if open ended. Treatment level and flow data unique to each facility were used to complete the CWNS dataset for that facility.

Total nitrogen and suspended-sediment loads and identification of suspended-sediment sources in the Laurel Hill Creek watershed, Somerset County, Pennsylvania, water years 2010-11

USGS Publications Warehouse

Sloto, Ronald A.; Gellis, Allen C.; Galeone, Daniel G.

2012-01-01

Laurel Hill Creek is a watershed of 125 square miles located mostly in Somerset County, Pennsylvania, with small areas extending into Fayette and Westmoreland Counties. The upper part of the watershed is on the Pennsylvania Department of Environmental Protection 303(d) list of impaired streams because of siltation, nutrients, and low dissolved oxygen concentrations. The objectives of this study were to (1) estimate the annual sediment load, (2) estimate the annual nitrogen load, and (3) identify the major sources of fine-grained sediment using the sediment-fingerprinting approach. This study by the U.S. Geological Survey (USGS) was done in cooperation with the Somerset County Conservation District. Discharge, suspended-sediment, and nutrient data were collected at two streamflow-gaging stations—Laurel Hill Creek near Bakersville, Pa., (station 03079600) and Laurel Hill Creek at Ursina, Pa., (station 03080000)—and one ungaged stream site, Laurel Hill Creek below Laurel Hill Creek Lake at Trent (station 03079655). Concentrations of nutrients generally were low. Concentrations of ammonia were less than 0.2 milligrams per liter (mg/L), and concentrations of phosphorus were less than 0.3 mg/L. Most concentrations of phosphorus were less than the detection limit of 0.02 mg/L. Most water samples had concentrations of nitrate plus nitrite less than 1.0 mg/L. At the Bakersville station, concentrations of total nitrogen ranged from 0.63 to 1.3 mg/L in base-flow samples and from 0.57 to 1.5 mg/L in storm composite samples. Median concentrations were 0.88 mg/L in base-flow samples and 1.2 mg/L in storm composite samples. At the Ursina station, concentrations of total nitrogen ranged from 0.25 to 0.92 mg/L in base-flow samples; the median concentration was 0.57 mg/L. The estimated total nitrogen load at the Bakersville station was 262 pounds (lb) for 11 months of the 2010 water year (November 2009 to September 2010) and 266 lb for the 2011 water year. Most of the total nitrogen loading was from stormflows. The stormflow load accounted for 76.6 percent of the total load for the 2010 water year and 80.6 percent of the total load for the 2011 water year. The estimated monthly total nitrogen loads were higher during the winter and spring (December through May) than during the summer (June through August). For the Bakersville station, the estimated suspended-sediment load (SSL) was 17,700 tons for 11 months of the 2010 water year (November 2009 to September 2010). The storm beginning January 24, 2010, provided 34.4 percent of the annual SSL, and the storm beginning March 10, 2010, provided 31.9 percent of the annual SSL. Together, these two winter storms provided 66 percent of the annual SSL for the 2010 water year. For the 2011 water year, the estimated annual SSL was 13,500 tons. For the 2011 water year, the SSLs were more evenly divided among storms than for the 2010 water year. Seven of 37 storms with the highest SSLs provided a total of 65.7 percent of the annual SSL for the 2011 water year; each storm provided from 4.6 to 12.3 percent of the annual SSL. The highest cumulative SSL for the 2010 and 2011 water years generally occurred during the late winter. Stormflows with the highest peak discharges generally carried the highest SSL. The sediment-fingerprinting approach was used to quantify sources of fine-grained suspended sediment in the watershed draining to the Laurel Hill Creek near Bakersville streamflow-gaging station. Sediment source samples were collected from five source types: 20 from cropland, 9 from pasture, 18 from forested areas, 20 from unpaved roads, and 23 from streambanks. At the Bakersville station, 10 suspended-sediment samples were collected during 6 storms for sediment-source analysis. Thirty-five tracers from elemental analysis and 4 tracers from stable isotope analysis were used to fingerprint the source of sediment for the 10 storm samples. Statistical analysis determined that cropland and pasture could not be discriminated by the set of tracers and were combined into one source group—agriculture. Stepwise discriminant function analysis determined that 11 tracers best described the 4 sources. An "unmixing" model applied to the 11 tracers showed that agricultural land (cropland and pasture) was the major source of sediment, contributing an average of 53 percent of the sediment for the 10 storm samples. Streambanks, unpaved roads, and forest contributions for the 10 storm samples averaged 30, 17, and 0 percent, respectively. Agriculture was the major contributor of sediment during the highest sampled stormflows. The highest stormflows also produced the highest total nitrogen and suspended-sediment loads.

Improved vertical displacements induced by a refined thermal expansion model and its quantitative analysis in GPS height time series

NASA Astrophysics Data System (ADS)

Wang, Kaihua; Chen, Hua; Jiang, Weiping; Li, Zhao; Ma, Yifang; Deng, Liansheng

2018-04-01

There are apparent seasonal variations in GPS height time series, and thermal expansion is considered to be one of the potential geophysical contributors. The displacements introduced by thermal expansion are usually derived without considering the annex height and underground part of the monument (e.g. located on roof or top of the buildings), which may bias the geophysical explanation of the seasonal oscillation. In this paper, the improved vertical displacements are derived by a refined thermal expansion model where the annex height and underground depth of the monument are taken into account, and then 560 IGS stations are adopted to validate the modeled thermal expansion (MTE) displacements. In order to evaluate the impact of thermal expansion on GPS heights, the MTE displacements of 80 IGS stations with less data discontinuities are selected to compare with their observed GPS vertical (OGV) displacements with the modeled surface loading (MSL) displacements removed in advance. Quantitative analysis results show the maximum annual and semiannual amplitudes of the MTE are 6.65 mm (NOVJ) and 0.51 mm (IISC), respectively, and the maximum peak-to-peak oscillation of the MTE displacements can be 19.4 mm. The average annual amplitude reductions are 0.75 mm and 1.05 mm respectively after removing the MTE and MSL displacements from the OGV, indicating the seasonal oscillation induced by thermal expansion is equivalent to >75% of the impact of surface loadings. However, there are rarely significant reductions for the semiannual amplitude. Given the result in this study that thermal expansion can explain 17.3% of the annual amplitude in GPS heights on average, it must be precisely modeled both in GPS precise data processing and GPS time series analysis, especially for those stations located in the middle and high latitudes with larger annual temperature oscillation, or stations with higher monument.

Assessment of future climate change impacts on nonpoint source pollution in snowmelt period for a cold area using SWAT.

PubMed

Wang, Yu; Bian, Jianmin; Zhao, Yongsheng; Tang, Jie; Jia, Zhuo

2018-02-05

The source area of Liao River is a typical cold region in northeastern China, which experiences serious problems with agricultural nonpoint source pollution (NPS), it is important to understand future climate change impacts on NPS in the watershed. This issue has been investigated by coupling semi distributed hydrological model (SWAT), statistical downscaling model (SDSM) and global circulation model (GCMs). The results show that annual average temperature would rise by 2.1 °C (1.3 °C) in the 2080 s under scenario RCP8.5 (RCP4.5), and annual precipitation would increase by 67 mm (33 mm). The change in winter temperature and precipitation is most significant with an increase by 0.23 °C/10a (0.17 °C/10a) and 1.94 mm/10a (2.78 mm/10a). The future streamflow, TN and TP loads would decrease by 19.05% (10.59%), 12.27% (8.81%) and 10.63% (6.11%), respectively. Monthly average streamflow, TN and TP loads would decrease from March to November, and increase from December to February. This is because the increased precipitation and temperature in winter, which made the spring snowpack melting earlier. These study indicate the trends of nonpoint source pollution during the snowmelt period under climate change conditions, accordingly adaptation measures will be necessary.

Wet and dry nitrogen deposition in the central Sichuan Basin of China

NASA Astrophysics Data System (ADS)

Kuang, Fuhong; Liu, Xuejun; Zhu, Bo; Shen, Jianlin; Pan, Yuepeng; Su, Minmin; Goulding, Keith

2016-10-01

Reactive nitrogen (Nr) plays a key role in the atmospheric environment and its deposition has induced large negative impacts on ecosystem health and services. Five-year continuous in-situ monitoring of N deposition, including wet (total nitrogen (WTN), total dissolved nitrogen (WTDN), dissolved organic nitrogen (WDON), ammonium nitrogen (WAN) and nitrate nitrogen (WNN)) and dry (DNH3, DHNO3, DpNH4+, DpNO3- and DNO2) deposition, had been conducted since August 2008 to December 2013 (wet) and May 2011 to December 2013 (dry) in Yan-ting, China, a typical agricultural area in the central Sichuan Basin. Mean annual total N deposition from 2011 to 2013 was 30.8 kg N ha-1 yr-1, and speculated that of 2009 and 2010 was averaged 28.2 kg N ha-1 yr-1, respectively. Wet and dry N deposition accounted for 76.3% and 23.7% of annual N deposition, respectively. Reduced N (WAN, DNH3 and DpNH4+) was 1.7 times of oxidized N (WNN, DHNO3, DNO2 and DpNO3-) which accounted for 50.9% and 30.3% of TN, respectively. Maximum loadings of all N forms of wet deposition, gaseous NH3, HNO3 and particulate NH4+ in dry deposition occurred in summer and minimum loadings in winter. Whether monthly, seasonal or annual averaged, dissolved N accounted for more than 70% of the total. N deposition in the central Sichuan Basin increased during the sampling period, especially that of ammonium compounds, and has become a serious threat to local aquatic ecosystems, the surrounding forest and other natural or semi-natural ecosystems in the upper reaches of the Yangtze River.

Systems analysis techniques for annual cycle thermal energy storage solar systems

NASA Astrophysics Data System (ADS)

Baylin, F.

1980-07-01

Community-scale annual cycle thermal energy storage solar systems are options for building heat and cooling. A variety of approaches are feasible in modeling ACTES solar systems. The key parameter in such efforts, average collector efficiency, is examined, followed by several approaches for simple and effective modeling. Methods are also examined for modeling building loads for structures based on both conventional and passive architectural designs. Two simulation models for sizing solar heating systems with annual storage are presented. Validation is presented by comparison with the results of a study of seasonal storage systems based on SOLANSIM, an hour-by-hour simulation. These models are presently used to examine the economic trade-off between collector field area and storage capacity. Programs directed toward developing other system components such as improved tanks and solar ponds or design tools for ACTES solar systems are examined.

Water-quality assessment of the Lower Susquehanna River Basin, Pennsylvania and Maryland; sources, characteristics, analysis and limitations of nutrient and suspended-sediment data, 1975-90

USGS Publications Warehouse

Hainly, R.A.; Loper, C.A.

1997-01-01

This report describes analyses of available information on nutrients and suspended sediment collected in the Lower Susquehanna River Basin during water years 1975-90. Most of the analyses were applied to data collected during water years 1980-89. The report describes the spatial and temporal availability of nutrient and suspended-sediment data and presents a preliminary concept of the spatial and temporal patterns of concentrations and loads within the basin. Where data were available, total and dissolved forms of nitrogen and phosphorus species from precipitation, surface water, ground water, and springwater, and bottom material from streams and reservoirs were evaluated. Suspended-sediment data from streams also were evaluated. The U.S. Geological Survey National Water Information System (NWIS) database was selected as the primary database for the analyses. Precipitation-quality data from the National Atmospheric Deposition Program (NADP) and bottom-material-quality data from the National Uranium Resource Evaluation (NURE) were used to supplement the water-quality data from NWIS. Concentrations of nutrients were available from 3 precipitation sites established for longterm monitoring purposes, 883 wells (854 synoptic areal survey sites and 29 project and research sites), 23 springs (17 synoptic areal survey sites and 6 project and research sites), and 894 bottom-material sites (840 synoptic areal survey sites and 54 project and research sites). Concentrations of nutrients and (or) suspended sediment were available from 128 streams (36 long-term monitoring sites, 51 synoptic areal survey sites, and 41 project and research sites). Concentrations of nutrients and suspended sediment in streams varied temporally and spatially and were related to land use, agricultural practices, and streamflow. A general north-to-south pattern of increasing median nitrate concentrations, from 2 to 5 mg/L, was detected in samples collected in study unit streams. In streams that drain areas dominated by agriculture, concentrations of nutrients and suspended sediment tend to be elevated with respect to those found in areas of other land-use types and are related to the amount of commercial fertilizer and animal manure applied to the area drained by the streams. Animal manure is the dominant source of nitrogen for the streams in the lower, agricultural part of the basin. Concentrations of nutrients in samples from wells varied with season and well depth and were related to hydrogeologic setting. Median concentrations of nitrate were 2.5 and 3.5 mg/L for wells drawing water at depths of 0 to 100 ft and 101 to 200 ft, respectively. The lowest median concentrations for nitrate in ground water from wells were generally found in siliciclastic-bedrock, forested settings of the Ridge and Valley Physiographic Province, and the highest were found in carbonate-bedrock agricultural settings of the Piedmont Physiographic Province. Twenty-five percent of the measurements from wells in carbonate rocks in the Piedmont Physiographic Province exceeded the Pennsylvania drinking-water standard. An estimate of mass balance of nutrient loads within the Lower Susquehanna River Basin was produced by combining the available information on stream loads, atmosphericdeposition loads, commercial-fertilizer applications, animal-manure production, privateseptic-system nonpoint-source loads, and municipal and industrial point-source loads. The percentage of the average annual nitrate load carried in base flow of streams in the study unit ranged from 45 to 76 percent, and the average annual phosphorus load carried in base flow ranged from 20 to 33 percent. Average annual yields of nutrients and suspended sediment from tributary basins are directly related to percentage of drainage area in agriculture and inversely to drainage area. Information required to compute loads of nitrogen and phosphorus were available for all sources except atmospheric deposition, for which only nitrogen data were available. Atmospheric deposition is the dominant source of nitrogen for the mostly forested basins draining the upper half of the study unit. The estimate of total annual nitrogen load to the study unit from precipitation is 98.8 million pounds. Nonpoint and point sources of nutrients were estimated. Nonpoint and point sources combined, including atmospheric deposition, provide a potential annual load of 390 million pounds of nitrogen and 79.5 million pounds of phosphorus. The range of percentages of the estimated nonpoint and point sources that were measured in the stream was 20 to 47 percent for nitrogen and 6 to 14 percent for phosphorus. On the average, the Susquehanna River discharges 141,000 pounds of nitrogen and 7,920 pounds of phosphorus to the Lower Susquehanna River reservoir system each year. About 98 percent of the nitrogen and 60 percent of the phosphorus passes through the reservoir system. Interpretations of available water-quality data and conclusions about the water quality of the Lower Susquehanna River Basin were limited by the scarcity of certain types of water-quality data and current ancillary data. A more complete assessment of the water quality of the basin with respect to nutrients and suspended sediment would be enhanced by the availability of additional data for multiple samples over time from all water environments; samples from streams in the northern and western part of the basin; samples from streams and springs throughout the basin during high base-flow or stormflow conditions; and information on current land-use, and nutrient loading from all types of land-use settings.

Magnitudes and Sources of Catchment Sediment: When A + B Doesn't Equal C

NASA Astrophysics Data System (ADS)

Simon, A.

2015-12-01

The export of land-based sediments to receiving waters can cause degradation of water quality and habitat, loss of reservoir capacity and damage to reef ecosystems. Predictions of sources and magnitudes generally come from simulations using catchment models that focus on overland flow processes at the expense of gully and channel processes. This is not appropriate for many catchments where recent research has shown that the dominant erosion sources have shifted from the uplands and fields following European Settlement, to the alluvial valleys today. Still, catchment models which fail to adequately address channel and bank processes are still the overwhelming choice by resource agencies to help manage sediment export. These models often utilize measured values of sediment load at the river mouth to "calibrate" the magnitude of loads emanating from uplands and fields. The difference between the sediment load at the mouth and the simulated upland loading is then proportioned to channel sources.Bank erosion from the Burnett River (a "Reef Catchment" in eastern Queensland) was quantified by comparisons of bank-top locations and by numerical modeling using BSTEM. Results show that bank-derived sediment contributes between 44 and 73% of the sediment load being exported to the Coral Sea. In comparison reported results from a catchment model showed bank contributions of 8%. In absolute terms, this is an increase in the reported average, annual rate of bank erosion from 0.175 Mt/y to 2.0 Mt/y.In the Hoteo River, New Zealand, a rural North Island catchment characterized by resistant cohesive sediments, bank erosion was found to contribute at least 48% of the total specific yield of sediment. Combining the bank-derived, fine-grained loads from some of the major tributaries gives a total, average annual loading rate for fine material of about 10,900 t/y for the studied reaches in the Hoteo River System. If the study was extended to include the lower reaches of the main stem channel and other tributary reaches, this percentage would be higher. Similar studies in the United States using combinations of empirical and numerical modeling techniques have also disclosed that bank-derived sediment can be the major source of sediment in many catchments. An approach to improve the accuracy of predictions is proposed.

Suspended Sediment Loads and Tributary Inputs in the Mississippi River below St. Louis, MO, 1990-2013 Compared With Earlier Results

NASA Astrophysics Data System (ADS)

Allison, M. A.; Biedenharn, D. S.; Dahl, T. A.; Kleiss, B.; Little, C. D.

2017-12-01

Annual suspended sediment loads and water discharges were calculated in the Mississippi River mainstem channel, and at the most downstream gaging station for major tributaries, from below the Missouri confluence near St. Louis, MO to Belle Chasse, LA, as well as down the Atchafalaya distributary for water years 1990 to 2013. The purpose of the present study was to assess changes in the Mississippi River sediment budget over the past half century, and to examine the continuing role that anthropogenic (e.g., dams, river control works, soil conservation practices) and natural (e.g., rainfall and denudation rates) factors have in controlling these changes. Sixteen of the 17 measured Mississippi River tributaries decreased in total suspended sediment load) from 1970-1978 to 1990-2013. The largest decreases occurred in the 2nd (Ohio River, 41% of 1970-1978) and 4th (Arkansas River, 45% of 1970-1978) largest water sources to the Mississippi. The Missouri River remains the largest Mississippi River tributary in terms of average annual suspended sediment flux; its relative contribution increased from 38% to 51% of the total flux from the 17 measured tributaries, even as its total suspended flux declined by 13%. Averaged over the period of study (WY 1990-2013), water flux increased by 468% and sediment flux increased by 37,418% downstream from the Gavin's Point Dam to the confluence with the Mississippi. Possible reasons for this disproportional increase in suspended sediment load downstream include sediment-rich contributions from 2nd order rivers below the dams and channel incision. Suggested station improvements to the system include improved monitoring of the Upper Mississippi and Arkansas River tributaries, establishing additional mainstem stations in the reach between Thebes, IL and Arkansas City, AR, and standardization of laboratory and field methodologies to eliminate a major source of station-to-station and time-series variability in the sediment budgeting.

Combined impacts of current and future dust deposition and regional warming on Colorado River Basin snow dynamics and hydrology

USGS Publications Warehouse

Deems, Jeffrey S.; Painter, Thomas H.; Barsugli, Joseph J.; Belnap, Jayne; Udall, Bradley

2013-01-01

The Colorado River provides water to 40 million people in seven western states and two countries and to 5.5 million irrigated acres. The river has long been overallocated. Climate models project runoff losses of 5–20% from the basin by mid-21st century due to human-induced climate change. Recent work has shown that decreased snow albedo from anthropogenic dust loading to the CO mountains shortens the duration of snow cover by several weeks relative to conditions prior to western expansion of the US in the mid-1800s, and advances peak runoff at Lees Ferry, Arizona, by an average of 3 weeks. Increases in evapotranspiration from earlier exposure of soils and germination of plants have been estimated to decrease annual runoff by more than 1.0 billion cubic meters, or ~5% of the annual average. This prior work was based on observed dust loadings during 2005–2008; however, 2009 and 2010 saw unprecedented levels of dust loading on snowpacks in the Upper Colorado River Basin (UCRB), being on the order of 5 times the 2005–2008 loading. Building on our prior work, we developed a new snow albedo decay parameterization based on observations in 2009/10 to mimic the radiative forcing of extreme dust deposition. We convolve low, moderate, and extreme dust/snow albedos with both historic climate forcing and two future climate scenarios via a delta method perturbation of historic records. Compared to moderate dust, extreme dust absorbs 2× to 4× the solar radiation, and shifts peak snowmelt an additional 3 weeks earlier to a total of 6 weeks earlier than pre-disturbance. The extreme dust scenario reduces annual flow volume an additional 1% (6% compared to pre-disturbance), a smaller difference than from low to moderate dust scenarios due to melt season shifting into a season of lower evaporative demand. The sensitivity of flow timing to dust radiative forcing of snow albedo is maintained under future climate scenarios, but the sensitivity of flow volume reductions decreases with increased climate forcing. These results have implications for water management and suggest that dust abatement efforts could be an important component of any climate adaptation strategies in the UCRB.

Application of modified export coefficient method on the load estimation of non-point source nitrogen and phosphorus pollution of soil and water loss in semiarid regions.

PubMed

Wu, Lei; Gao, Jian-en; Ma, Xiao-yi; Li, Dan

2015-07-01

Chinese Loess Plateau is considered as one of the most serious soil loss regions in the world, its annual sediment output accounts for 90 % of the total sediment loads of the Yellow River, and most of the Loess Plateau has a very typical characteristic of "soil and water flow together", and water flow in this area performs with a high sand content. Serious soil loss results in nitrogen and phosphorus loss of soil. Special processes of water and soil in the Loess Plateau lead to the loss mechanisms of water, sediment, nitrogen, and phosphorus are different from each other, which are greatly different from other areas of China. In this study, the modified export coefficient method considering the rainfall erosivity factor was proposed to simulate and evaluate non-point source (NPS) nitrogen and phosphorus loss load caused by soil and water loss in the Yanhe River basin of the hilly and gully area, Loess Plateau. The results indicate that (1) compared with the traditional export coefficient method, annual differences of NPS total nitrogen (TN) and total phosphorus (TP) load after considering the rainfall erosivity factor are obvious; it is more in line with the general law of NPS pollution formation in a watershed, and it can reflect the annual variability of NPS pollution more accurately. (2) Under the traditional and modified conditions, annual changes of NPS TN and TP load in four counties (districts) took on the similar trends from 1999 to 2008; the load emission intensity not only is closely related to rainfall intensity but also to the regional distribution of land use and other pollution sources. (3) The output structure, source composition, and contribution rate of NPS pollution load under the modified method are basically the same with the traditional method. The average output structure of TN from land use and rural life is about 66.5 and 17.1 %, the TP is about 53.8 and 32.7 %; the maximum source composition of TN (59 %) is farmland; the maximum source composition of TP (38.1 %) is rural life; the maximum contribution rates of TN and TP in Baota district are 36.26 and 39.26 %, respectively. Results may provide data support for NPS pollution prevention and control in the loess hilly and gully region and also provide scientific reference for the protection of ecological environment of the Loess Plateau in northern Shaanxi.

Feasibility Study of Grid Connected PV-Biomass Integrated Energy System in Egypt

NASA Astrophysics Data System (ADS)

Barakat, Shimaa; Samy, M. M.; Eteiba, Magdy B.; Wahba, Wael Ismael

2016-10-01

The aim of this paper is to present a feasibility study of a grid connected photovoltaic (PV) and biomass Integrated renewable energy (IRE) system providing electricity to rural areas in the Beni Suef governorate, Egypt. The system load of the village is analyzed through the environmental and economic aspects. The model has been designed to provide an optimal system configuration based on daily data for energy availability and demands. A case study area, Monshaet Taher village (29° 1' 17.0718"N, 30° 52' 17.04"E) is identified for economic feasibility in this paper. HOMER optimization model plan imputed from total daily load demand, 2,340 kWh/day for current energy consuming of 223 households with Annual Average Insolation Incident on a Horizontal Surface of 5.79 (kWh/m2/day) and average biomass supplying 25 tons / day. It is found that a grid connected PV-biomass IRE system is an effective way of emissions reduction and it does not increase the investment of the energy system.

Impacts of climate change on TN load and its control in a River Basin with complex pollution sources.

PubMed

Yang, Xiaoying; Warren, Rachel; He, Yi; Ye, Jinyin; Li, Qiaoling; Wang, Guoqing

2018-02-15

It is increasingly recognized that climate change could affect the quality of water through complex natural and anthropogenic mechanisms. Previous studies on climate change and water quality have mostly focused on assessing its impact on pollutant loads from agricultural runoff. A sub-daily SWAT model was developed to simulate the discharge, transport, and transformation of nitrogen from all known anthropogenic sources including industries, municipal sewage treatment plants, concentrated and scattered feedlot operations, rural households, and crop production in the Upper Huai River Basin. This is a highly polluted basin with total nitrogen (TN) concentrations frequently exceeding Class V of the Chinese Surface Water Quality Standard (GB3838-2002). Climate change projections produced by 16 Global Circulation Models (GCMs) under the RCP 4.5 and RCP 8.5 scenarios in the mid (2040-2060) and late (2070-2090) century were used to drive the SWAT model to evaluate the impacts of climate change on both the TN loads and the effectiveness of three water pollution control measures (reducing fertilizer use, constructing vegetative filter strips, and improving septic tank performance) in the basin. SWAT simulation results have indicated that climate change is likely to cause an increase in both monthly average and extreme TN loads in February, May, and November. The projected impact of climate change on TN loads in August is more varied between GCMs. In addition, climate change is projected to have a negative impact on the effectiveness of septic tanks in reducing TN loads, while its impacts on the other two measures are more uncertain. Despite the uncertainty, reducing fertilizer use remains the most effective measure for reducing TN loads under different climate change scenarios. Meanwhile, improving septic tank performance is relatively more effective in reducing annual TN loads, while constructing vegetative filter strips is more effective in reducing annual maximum monthly TN loads. Copyright © 2017 Elsevier B.V. All rights reserved.

Trends in nitrogen concentration and nitrogen loads entering the South Shore Estuary Reserve from streams and ground-water discharge in Nassau and Suffolk counties, Long Island, New York, 1952–97

USGS Publications Warehouse

Monti, Jack; Scorca, Michael P.

2003-01-01

The 13 major south-shore streams in Nassau and Suffolk Counties, Long Island, New York with adequate long-term (1971-97) water-quality records, and 192 south-shore wells with sufficient water-quality data, were selected for analysis of geographic, seasonal, and long-term trends in nitrogen concentration. Annual total nitrogen loads transported to the South Shore Estuary Reserve (SSER) from 11 of these streams were calculated using long-term discharge records. Nitrogen loads from shallow and deep ground water also were calculated using simulated ground-water discharge of 1968-83 hydrologic conditions.Long-term declines in stream discharge occurred in East Meadow Brook, Bellmore Creek and Massapequa Creek in response to extensive sewering in Nassau County. The smallest longterm annual discharge to the SSER was from the westernmost stream, Pines Brook, which is in an area in which the water table has been lowered by sewers since 1952. The three largest average annual discharges to the SSER were from the Connetquot River, Carlls River, and Carmans River in Suffolk County; the discharges from each of these streams were at least twice those of the other streams considered in this study.Total nitrogen concentrations in streams show a geographic trend with a general eastward increase in median total nitrogen concentration in Nassau County and a decreasing trend from Massapequa Creek eastward into Suffolk County. Total nitrogen concentrations in streams generally are lowest during summer and highest in winter as a result of seasonal fluctuations in chemical reactions and biological activity. The greatest seasonal difference in median total nitrogen concentration was at Carlls River with values of 3.4 and 4.2 mg/L (milligrams per liter) as N during summer (April through September) and winter (October through March), respectively. Streams affected by the completion of sewer districts show long-term (1971-97) trends of decreasing total nitrogen concentration and streams showing an increase in total nitrogen concentration are in unsewered areas with increased urbanization.Discharges from shallow ground water (upper glacial aquifer) and deep ground water (upper part of Magothy aquifer) were simulated from a ground-water-flow model calibrated to steadystate (1968-83) conditions. Simulated discharges from shallow-ground-water system in Nassau County were 10,700 Mgal/yr (million gallons per year) or 40,500,000 m3/yr (cubic meters per year), and those from Suffolk County were 52,300 Mgal/yr or 198,000,000 m3/yr. Discharges from deep-ground-water system in Nassau County were 4,900 Mgal/yr or 18,500,000 m3/yr, and those in Suffolk County were 12,700 Mgal/yr or 48,200,000 m3/yr.Ground-water concentrations of nitrogen decrease with depth and from west to east. The shallow ground water median nitrogen concentration for each county was determined using 1,155 samples collected at 167 shallow wells (125 feet deep or less) within 1 mile of the shore. The deep ground water median nitrate concentration (nitrate represented almost all of the total nitrogen) for each county was determined using 112 samples collected at 25 deep wells (greater than 125 feet deep) within 1 mile of the shore. The median nitrogen concentration for the shallow and median nitrate concentration for the deep ground water in Nassau County were 3.85 and 0.15 mg/L as N, during 1952–97; the corresponding concentrations for Suffolk County were 1.74 and <0.10 (less than 0.10) mg/L as N, during 1952–97.Nitrogen loads discharged from streams to the SSER for each year during 1972–97 were calculated as the annual total nitrogen concentration multiplied by the annual discharge. These values were calculated only for the seven streams for which sufficient data were available. The largest long-term (1972–97) average annual nitrogen load from Carlls River was 104 ton/yr or 94,300 kg/yr—about twice that of Connetquot River (54 ton/yr or 48,900 kg/yr) and over three times that of Carmans River (33 ton/yr or 29,900 kg/yr). The smallest annual mean nitrogen load was from Pines Brook, which has the lowest annual mean discharge of all streams analyzed.The nitrogen load carried to the SSER by ground-water discharge in shallow-ground-water system in Nassau and Suffolk Counties was calculated as the simulated discharge for each county multiplied by the respective median nitrogen concentration, and loads from deep-ground-water system were calculated as the simulated discharge for each county multiplied by the respective median nitrate concentration. All discharges were obtained from the U.S. Geological Survey's Long Island ground-water-flow model. The resultant nitrogen loads discharged to the SSER from shallow ground water were 172 ton/yr (156,000 kg/yr) from Nassau County and 380 ton/yr (345,000 kg/yr) from Suffolk County; equaling 552 ton/yr entering the SSER. Those from deep ground water were 3 ton/yr (2,700 kg/yr) from Nassau County and <0.5 ton/yr (480 kg/yr) from Suffolk County; equaling about 3.5 ton/yr entering the SSER.The sum of both stream loads and groundwater loads results in the total load to the SSER. The largest calculated total nitrogen load entering the SSER from both streams and ground water occurred in 1979 with a total load of 1,260 ton/yr (1,140,000 kg/yr). The smallest calculated nitrogen load entering the SSER occurred in 1995 with a total load of 725 ton/yr (658,000 kg/yr).

Hydrosalinity studies of the Virgin River, Dixie Hot Springs, and Littlefield Springs, Utah, Arizona, and Nevada

USGS Publications Warehouse

Gerner, Steven J.; Thiros, Susan A.; Gerner, Steven J.; Thiros, Susan A.

2014-01-01

The Virgin River contributes a substantial amount of dissolved solids (salt) to the Colorado River at Lake Mead in the lower Colorado River Basin. Degradation of Colorado River water by the addition of dissolved solids from the Virgin River affects the suitability of the water for municipal, industrial, and agricultural use within the basin. Dixie Hot Springs in Utah are a major localized source of dissolved solids discharging to the Virgin River. The average measured discharge from Dixie Hot Springs during 2009–10 was 11.0 cubic feet per second (ft3/s), and the average dissolved-solids concentration was 9,220 milligrams per liter (mg/L). The average dissolved-solids load—a measurement that describes the mass of salt that is transported per unit of time—from Dixie Hot Springs during this period was 96,200 tons per year (ton/yr). Annual dissolved-solids loads were estimated at 13 monitoring sites in the Virgin River Basin from streamflow data and discrete measurements of dissolved-solids concentrations and (or) specific conductance. Eight of the sites had the data needed to estimate annual dissolved-solids loads for water years (WYs) 1999 through 2010. During 1999–2010, the smallest dissolved-solids loads in the Virgin River were upstream of Dixie Hot Springs (59,900 ton/yr, on average) and the largest loads were downstream of Littlefield Springs (298,200 ton/yr, on average). Annual dissolved-solids loads were smallest during 2002–03, which was a period of below normal precipitation. Annual dissolved-solids loads were largest during 2005—a year that included a winter rain storm that resulted in flooding throughout much of the Virgin River Basin. An average seepage loss of 26.7 ft3/s was calculated from analysis of monthly average streamflow from July 1998 to September 2010 in the Virgin River for the reach that extends from just upstream of the Utah/Arizona State line to just above the Virgin River Gorge Narrows. Seepage losses from three river reaches in the Virgin River Gorge containing known fault zones accounted for about 48 percent of this total seepage loss. An additional seepage loss of 6.7 ft3/s was calculated for the reach of the Virgin River between Bloomington, Utah, and the Utah/Arizona State line. This loss in flow is small compared to total flow in the river and is comparable to the rated error in streamflow measurements in this reach; consequently, it should be used with caution. Littlefield Springs were studied to determine the fraction of its discharge that originates as upstream seepage from the Virgin River and residence time of this water in the subsurface. Geochemical and environmental tracer data from groundwater and surface-water sites in the Virgin River Gorge area suggest that discharge from Littlefield Springs is a mixture of modern (post-1950s) seepage from the Virgin River upstream of the springs and older groundwater from a regional carbonate aquifer. Concentrations of the chlorofluorocarbons (CFCs) CFC-12 and CFC-113, chloride/fluoride and chloride/bromide ratios, and the stable isotope deuterium indicate that water discharging from Littlefield Springs is about 60 percent seepage from the Virgin River and about 40 percent discharge from the regional carbonate aquifer. The river seepage component was determined to have an average subsurface traveltime of about 26 ±1.6 years before discharging at Littlefield Springs. Radiocarbon data for Littlefield Springs suggest groundwater ages from 1,000 to 9,000 years. Because these are mixed waters, the component of discharge from the carbonate aquifer is likely much older than the groundwater ages suggested by the Littlefield Springs samples. If the dissolved-solids load from Dixie Hot Springs to the Virgin River were reduced, the irrigation water subsequently applied to agricultural fields in the St. George and Washington areas, which originates as water from the Virgin River downstream of Dixie Hot Springs, would have a lower dissolved-solids concentration. Dissolved-solids concentrations in excess irrigation water draining from the agricultural fields are about 1,700 mg/L higher than the concentrations in the Virgin River water that is currently (2014) used for irrigation that contains inflow from Dixie Hot Springs; this increase results from evaporative concentration and dissolution of mineral salts in the irrigated agricultural fields. The water samples collected from drains downgradient from the irrigated areas are assumed to include the dissolution of all available minerals precipitated in the soil during the previous irrigation season. Based on this assumption, a change to more dilute irrigation water will not dissolve additional minerals and increase the dissolved-solids load in the drain discharge. Following the hypothetical reduction of salts from Dixie Hot Springs, which would result in more dilute Virgin River irrigation water than is currently used, the dissolution of minerals left in the soil from the previous irrigation season would result in a net increase in dissolved-solids concentrations in the drain discharge, but this increase should only last one irrigation season. After one (or several) seasons of irrigating with more dilute irrigation water, mineral precipitation and subsequent re-dissolution beneath the agricultural fields should be greatly reduced, leading to a reduction in dissolved-solids load to the Virgin River below the agricultural drains. A mass-balance model was used to predict changes in the dissolved-solids load in the Virgin River if the salt discharging from Dixie Hot Springs were reduced or removed. Assuming that 33.4 or 26.7 ft3/s of water seeps from the Virgin River to the groundwater system upstream of the Virgin River Gorge Narrows, the immediate hypothetical reduction in dissolved-solids load in the Virgin River at Littlefield, Arizona is estimated to be 67,700 or 71,500 ton/yr, respectively. The decrease in dissolved-solids load in seepage from the Virgin River to the groundwater system is expected to reduce the load discharging from Littlefield Springs in approximately 26 years, the estimated time lag between seepage from the river and discharge of the seepage water, after subsurface transport, from Littlefield Springs. At that time, the entire reduction in dissolved solids seeping from the Virgin River is expected to be realized as a reduction in dissolved solids discharging from Littlefield Springs, resulting in an additional reduction of 24,700 ton/yr (based on 33.4 ft3/s of seepage loss) or 21,000 ton/yr (based on 26.7 ft3/s of seepage loss) in the river’s dissolved-solids load at Littlefield.

50 CFR 218.21 - Permissible methods of taking.

Code of Federal Regulations, 2012 CFR

2012-10-01

... annually); (xv) Pygmy killer whale (Feresa attenuate)—15 (an average of 3 annually); (xvi) Killer whale... dolphin (Lagenorhynchus acutus)—100 (an average of 20 annually); (x) Pilot whales (Globicephala sp.)—100 (an average of 20 annually); (xi) Dwarf or pygmy sperm whales (Kogia sp.)—15 (an average of 3 annually...

50 CFR 218.21 - Permissible methods of taking.

Code of Federal Regulations, 2010 CFR

2010-10-01

... annually); (xv) Pygmy killer whale (Feresa attenuate)—15 (an average of 3 annually); (xvi) Killer whale... dolphin (Lagenorhynchus acutus)—100 (an average of 20 annually); (x) Pilot whales (Globicephala sp.)—100 (an average of 20 annually); (xi) Dwarf or pygmy sperm whales (Kogia sp.)—15 (an average of 3 annually...

50 CFR 218.21 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

... annually); (xv) Pygmy killer whale (Feresa attenuate)—15 (an average of 3 annually); (xvi) Killer whale... dolphin (Lagenorhynchus acutus)—100 (an average of 20 annually); (x) Pilot whales (Globicephala sp.)—100 (an average of 20 annually); (xi) Dwarf or pygmy sperm whales (Kogia sp.)—15 (an average of 3 annually...

50 CFR 218.11 - Permissible methods of taking.

Code of Federal Regulations, 2010 CFR

2010-10-01

... annually); (viii) Pilot whales (Globicephala sp.)—100 (an average of 20 annually); (ix) Dwarf or pygmy sperm whales (Kogia sp.)—15 (an average of 3 annually); (x) Beaked whales—100 (an average of 20 annually); (xi) Minke whales (Balaenoptera acutorostrata)—15 (an average of 3 annually). (2) Level A Harassment...

50 CFR 218.11 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

... annually); (viii) Pilot whales (Globicephala sp.)—100 (an average of 20 annually); (ix) Dwarf or pygmy sperm whales (Kogia sp.)—15 (an average of 3 annually); (x) Beaked whales—100 (an average of 20 annually); (xi) Minke whales (Balaenoptera acutorostrata)—15 (an average of 3 annually). (2) Level A Harassment...

50 CFR 218.11 - Permissible methods of taking.

Code of Federal Regulations, 2012 CFR

2012-10-01

... annually); (viii) Pilot whales (Globicephala sp.)—100 (an average of 20 annually); (ix) Dwarf or pygmy sperm whales (Kogia sp.)—15 (an average of 3 annually); (x) Beaked whales—100 (an average of 20 annually); (xi) Minke whales (Balaenoptera acutorostrata)—15 (an average of 3 annually). (2) Level A Harassment...

Estimating Critical Nitrogen Loads for a California Grassland

NASA Astrophysics Data System (ADS)

Weiss, S. B.

2007-12-01

Rigorously established critical nitrogen loads to protect biodiversity can be effective policy tools for addressing the insidious impacts of atmospheric N-deposition on ecosystems. This presentation describes methods for determining critical N-loads to a California grassland ecosystem by careful examination of the continuum from emissions, transport, atmospheric chemistry, deposition, ecosystem response, and impacts on biodiversity. Nutrient-poor soils derived from serpentinite bedrock support diverse native grasslands with dazzling wildflower displays and numerous threatened and endangered species, including the Bay checkerspot butterfly. Under moderate atmospheric N-deposition, these sites are rapidly invaded by introduced nitrophilous annual grasses in the absence of appropriate grazing or other management. Critical loads to this ecosystem have been approached by measurements of atmospheric concentrations of reactive N gases using Ogawa passive samplers and seasonally averaged deposition velocities. A regional-scale pollution gradient was complemented by a very local-scale pollution gradient extending a few hundred meters downwind of a heavily traveled road in a relatively unpolluted area. The local gradient suggests a critical load of 5 kg-N ha-1 a-1 or less. The passive monitor calculations largely agree with deposition calculated with the CMAQ model at 4 km scale. Emissions of NH3 from catalytic converters are the dominant N-source at the roadway site, and are a function of traffic volume and speed. Plant tissue N-content and 15N gradients support the existence of N-deposition gradients. The complexities of more detailed calculations and measurements specific to this ecosystem include seasonal changes in LAI, temporal coincidence of traffic emissions and stomatal conductance, surface moisture, changes in oxidized versus reduced N sources, and annual weather variation. The concept of a "critical cumulative load" may be appropriate over decadal time scales in this ecosystem and other semi-arid systems where N-export is minimal.

Comparison of sediment supply to San Francisco Bay from watersheds draining the Bay Area and the Central Valley of California

USGS Publications Warehouse

McKee, L.J.; Lewicki, M.; Schoellhamer, D.H.; Ganju, N.K.

2013-01-01

Quantifying suspended sediment loads is important for managing the world's estuaries in the context of navigation, pollutant transport, wetland restoration, and coastal erosion. To address these needs, a comprehensive analysis was completed on sediment supply to San Francisco Bay from fluvial sources. Suspended sediment, optical backscatter, velocity data near the head of the estuary, and discharge data obtained from the output of a water balance model were used to generate continuous suspended sediment concentration records and compute loads to the Bay from the large Central Valley watershed. Sediment loads from small tributary watersheds around the Bay were determined using 235 station-years of suspended sediment data from 38 watershed locations, regression analysis, and simple modeling. Over 16 years, net annual suspended sediment load to the head of the estuary from its 154,000 km2 Central Valley watershed varied from 0.13 to 2.58 (mean = 0.89) million metric t of suspended sediment, or an average yield of 11 metric t/km2/yr. Small tributaries, totaling 8145 km2, in the nine-county Bay Area discharged between 0.081 and 4.27 (mean = 1.39) million metric t with a mean yield of 212 metric t/km2/yr. The results indicate that the hundreds of urbanized and tectonically active tributaries adjacent to the Bay, which together account for just 5% of the total watershed area draining to the Bay and provide just 7% of the annual average fluvial flow, supply 61% of the suspended sediment. The small tributary loads are more variable (53-fold between years compared to 21-fold for the inland Central Valley rivers) and dominated fluvial sediment supply to the Bay during 10 out of 16 yr. If San Francisco Bay is typical of other estuaries in active tectonic or climatically variable coastal regimes, managers responsible for water quality, dredging and reusing sediment accumulating in shipping channels, or restoring wetlands in the world's estuaries may need to more carefully account for proximal small urbanized watersheds that may dominate sediment supply.

Concentrations and Loads of Organic Compounds and Trace Elements in Tributaries to Newark and Raritan Bays, New Jersey

USGS Publications Warehouse

Wilson, Timothy P.; Bonin, Jennifer L.

2007-01-01

A study was undertaken to determine the concentrations and loads of sediment and chemicals delivered to Newark and Raritan Bays by five major tributaries: the Raritan, Passaic, Rahway, Elizabeth, and Hackensack Rivers. This study was initiated by the State of New Jersey as Study I-C of the New Jersey Toxics Reduction Workplan for the New York-New Jersey Harbor, working under the NY-NJ Harbor Estuary Program (HEP) Contaminant Assessment and Reduction Program (CARP). The CARP is a comprehensive effort to evaluate the levels and sources of toxic contaminants to the tributaries and estuarine areas of the NY-NJ Harbor, including Newark and Raritan Bays. The Raritan and Passaic Rivers are large rivers (mean daily discharges of 1,189 and 1,132 cubic feet per second (ft3/s), respectively), that drain large, mixed rural/urban basins. The Elizabeth and Rahway Rivers are small rivers (mean daily discharges of 25.9 and 49.1 ft3/s, respectively) that drain small, highly urbanized and industrialized basins. The Hackensack River drains a small, mixed rural/urban basin, and its flow is highly controlled by an upstream reservoir (mean daily discharge of 90.4 ft3/s). These rivers flow into urbanized estuaries and ultimately, to the Atlantic Ocean. Each of these tributaries were sampled during two to four storm events, and twice each during low-flow discharge conditions. Samples were collected using automated equipment installed at stations adjacent to U.S. Geological Survey streamflow-gaging stations near the heads-of-tide of these rivers. Large-volume (greater than 50 liters of water and a target of 1 gram of sediment), flow-weighted composite samples were collected for chemical analysis using filtration to collect suspended particulates and exchange resin (XAD-2) to sequester dissolved contaminants. Composite whole-water samples were collected for dissolved polycyclic aromatic hydrocarbons (PAH) and for trace element analysis. Additional discrete grab samples were collected throughout each event for trace-element analysis, and multiple samples were collected for suspended sediment (SS), particulate carbon (POC), and dissolved organic carbon (DOC) analysis. The suspended sediment and exchange resin were analyzed for 114 polychlorinated biphenyls (PCBs, by US EPA method 1668A, modified), seven 2,3,7,8-substituted chlorinated dibenzo-p-dioxins (CDD) and 10 dibenzo-p-difurans (CDF) (by US EPA method 1613), 24 PAHs (by low-resolution isotope dilution/mass-spectral methods), 27 organo-chlorine pesticides (OCPs) (by high resolution isotope dilution/mass-spectral methods), and the trace elements mercury (Hg), methyl-mercury (MeHg), lead (Pb), and cadmium (Cd). Isotope dilution methods using gas chromatography and high-and low-resolution mass spectral (GC/MS) detection were used to accurately identify and quantify organic compounds in the sediment and water phases. Trace elements were measured using inductively coupled plasma-mass spectrometry and cold-vapor atomic fluorescence spectrometry methods. The loads of sediment, carbon, and chemicals were calculated for each storm and low-flow event sampled. Because only a few storm events were sampled, yearly loads of sediment were calculated from rating curves developed using historical SS and POC data. The average annual loads of sediment and carbon were calculated for the period 1975-2000, along with the loads for the selected water years being modeled as part of the New York New Jersey Harbor Estuary Program CARP. Comparison of loads calculated using the rating curve method to loads measured during the sampled storm events indicated that the rating curve method likely underpredicts annual loads. Average annual loads of suspended sediment in the tributaries were estimated to be 395,000 kilograms per year (kg/yr) in the Hackensack River, 417,000 kg/yr in the Elizabeth River, 882,000 kg/yr in the Rahway River, 22,700,000 kg/yr in the Passaic River, and 93,100,000 kg/yr in the Raritan River. Averag

Atmospheric nitrogen deposition to China: A model analysis on nitrogen budget and critical load exceedance

NASA Astrophysics Data System (ADS)

Zhao, Yuanhong; Zhang, Lin; Chen, Youfan; Liu, Xuejun; Xu, Wen; Pan, Yuepeng; Duan, Lei

2017-03-01

We present a national-scale model analysis on the sources and processes of inorganic nitrogen deposition over China using the GEOS-Chem model at 1/2° × 1/3° horizontal resolution. Model results for 2008-2012 are evaluated with an ensemble of surface measurements of wet deposition flux and gaseous ammonia (NH3) concentration, and satellite measurements of tropospheric NO2 columns. Annual total inorganic nitrogen deposition fluxes are simulated to be generally less than 10 kg N ha-1 a-1 in western China (less than 2 kg N ha-1 a-1 over Tibet), 15-50 kg N ha-1 a-1 in eastern China, and 16.4 kg N ha-1 a-1 averaged over China. Annual total deposition to China is 16.4 Tg N, with 10.2 Tg N (62%) from reduced nitrogen (NHx) and 6.2 Tg N from oxidized nitrogen (NOy). Domestic anthropogenic sources contribute 86% of the total deposition; foreign anthropogenic sources 7% and natural sources 7%. Annually 23% of domestically emitted NH3 and 36% for NOx are exported outside the terrestrial land of China. We find that atmospheric nitrogen deposition is about half of the nitrogen input from fertilizer application (29.6 Tg N a-1), and is much higher than that from natural biological fixation (7.3 Tg N a-1) over China. A comparison of nitrogen deposition with critical load estimates for eutrophication indicates that about 15% of the land over China experiences critical load exceedances, demonstrating the necessity of nitrogen emission controls to avoid potential negative ecological effects.

Distribution and transport of polychlorinated biphenyls in Little Lake Butte des Morts, Fox River, Wisconsin, April 1987-October 1988

USGS Publications Warehouse

House, L.B.

1995-01-01

The mass of PCB's transported from the lake in streamflow during 1987-88 was calculated to be 110 kilograms annually. The PCB's transport rate decreased 50 percent from 1987 to 1988, for the period April through September. Transport of PCB's was greatest during April and May of each year. The average flux rate of PCB's into the water column from the bottom sediment in the lake was estimated to be 1.2 milligrams per square meter per day. The PCB's load seems to increase at river discharges greater than 212 cubic meters per second. This increase in PCB's load might be caused by resuspension of PCB's-contaminated bottom-sediment deposits. There was little variation in PCB's load at flows less than 170 cubic meters per second. The bottom sediments are a continuing source of PCB's to Little Lake Butte des Morts and the lower Fox River.

Geochemical responses of forested catchments to bark beetle infestation: Evidence from high frequency in-stream electrical conductivity monitoring

NASA Astrophysics Data System (ADS)

Su, Ye; Langhammer, Jakub; Jarsjö, Jerker

2017-07-01

Under the present conditions of climate warming, there has been an increased frequency of bark beetle-induced tree mortality in Asia, Europe, and North America. This study analyzed seven years of high frequency monitoring of in-stream electrical conductivity (EC), hydro-climatic conditions, and vegetation dynamics in four experimental catchments located in headwaters of the Sumava Mountains, Central Europe. The aim was to determine the effects of insect-induced forest disturbance on in-stream EC at multiple timescales, including annual and seasonal average conditions, daily variability, and responses to individual rainfall events. Results showed increased annual average in-stream EC values in the bark beetle-infected catchments, with particularly elevated EC values during baseflow conditions. This is likely caused by the cumulative loading of soil water and groundwater that discharge excess amounts of substances such as nitrogen and carbon, which are released via the decomposition of the needles, branches, and trunks of dead trees, into streams. Furthermore, we concluded that infestation-induced changes in event-scale dynamics may be largely responsible for the observed shifts in annual average conditions. For example, systematic EC differences between baseflow conditions and event flow conditions in relatively undisturbed catchments were essentially eliminated in catchments that were highly disturbed by bark beetles. These changes developed relatively rapidly after infestation and have long-lasting (decadal-scale) effects, implying that cumulative impacts of increasingly frequent bark beetle outbreaks may contribute to alterations of the hydrogeochemical conditions in more vulnerable mountain regions.

Characterization of hydrology and salinity in the Dolores project area, McElmo Creek Region, southwest Colorado, 1978-2006

USGS Publications Warehouse

Richards, Rodney J.; Leib, Kenneth J.

2011-01-01

Increasing salinity loading in the Colorado River has become a major concern for agricultural and municipal water supplies. The Colorado Salinity Control Act was implemented in 1974 to protect and enhance the quality of water in the Colorado River Basin. The U.S. Geological Survey, in cooperation with the Bureau of Reclamation and the Colorado River Salinity Control Forum, summarized salinity reductions in the McElmo Creek basin in southwest Colorado as a result of salinity-control modifications and flow-regime changes that result from the Dolores Project, which consists of the construction of McPhee reservoir on the Dolores River and salinity control modifications along the irrigation water delivery system. Flow-adjusted salinity trends using S-LOADEST estimations for a streamgage on McElmo Creek (site 1), that represents outflow from the basin, indicates a decrease in salinity load by 39,800 tons from water year 1978 through water year 2006, which is an average decrease of 1,370 tons per year for the 29-year period. Annual-load calculations for a streamgage on Mud Creek (site 6), that represents outflow from a tributary basin, indicate a decrease of 7,300 tons from water year 1982 through water year 2006, which is an average decrease of 292 tons per year for the 25-year period. The streamgage Dolores River at Dolores, CO (site 17) was chosen to represent a background site that is not affected by the Dolores Project. Annual load calculations for site 17 estimated a decrease of about 8,600 tons from water year 1978 through water year 2006, which is an average decrease of 297 tons per year for the 29-year period. The trend in salinity load at site 17 was considered to be representative of a natural trend in the region. Typically, salinity concentrations at outflow sites decreased from the pre-Dolores Project period (water years 1978-1984) to the post-Dolores Project period (water years 2000-2006). The median salinity concentration for site 1 (main basin outflow) decreased from 2,210 milligrams per liter per day in the preperiod to 2,110 milligrams per liter per day in the postperiod. The median salinity concentration for site 6 (tributary outflow) increased from 3,370 milligrams per liter per day in the preperiod to 3,710 milligrams per liter per day in the postperiod. Salinity concentrations typically increased at inflow sites from the preperiod to the postperiod. Salinity concentrations increased from 178 milligrams per liter per day during the preperiod at Main Canal #1 (site 16) to 227 milligrams per liter per day during the postperiod at the Dolores Tunnel Outlet near Dolores, CO (site 15). Calculation of the historical flow regime in McElmo Creek was done using a water-budget analysis of the basin. During water years 2000-2006, an estimated 845,000 acre-feet of water was consumed by crops and did not return to the creek as streamflow. The remaining 76,000 acre-feet, or 10,900 acre-feet per year for the 7-year postperiod, was assumed to represent a historical flow condition. The historical flow of 10,900 acre-feet per year is equivalent to 15.1 cubic feet per second. Average total dissolved solids concentrations for water in each type of sedimentary rock were used to estimate natural salinity loads. Most surface-water sites used to fit the criteria needed to achieve a natural TDS concentration were springs. An average spring TDS value for sandstones geology in the basin was 350 milligrams per liter, and the average value for Mancos Shale geology was 4,000 milligrams per liter. The natural salinity loads in McElmo Creek were estimated to be 29,100 tons per year, which is 43 percent of the salinity load that was calculated for the postperiod.

An assessment of the suspended sediment rating curve approach for load estimation on the Rivers Bandon and Owenabue, Ireland

NASA Astrophysics Data System (ADS)

Harrington, Seán T.; Harrington, Joseph R.

2013-03-01

This paper presents an assessment of the suspended sediment rating curve approach for load estimation on the Rivers Bandon and Owenabue in Ireland. The rivers, located in the South of Ireland, are underlain by sandstone, limestones and mudstones, and the catchments are primarily agricultural. A comprehensive database of suspended sediment data is not available for rivers in Ireland. For such situations, it is common to estimate suspended sediment concentrations from the flow rate using the suspended sediment rating curve approach. These rating curves are most commonly constructed by applying linear regression to the logarithms of flow and suspended sediment concentration or by applying a power curve to normal data. Both methods are assessed in this paper for the Rivers Bandon and Owenabue. Turbidity-based suspended sediment loads are presented for each river based on continuous (15 min) flow data and the use of turbidity as a surrogate for suspended sediment concentration is investigated. A database of paired flow rate and suspended sediment concentration values, collected between the years 2004 and 2011, is used to generate rating curves for each river. From these, suspended sediment load estimates using the rating curve approach are estimated and compared to the turbidity based loads for each river. Loads are also estimated using stage and seasonally separated rating curves and daily flow data, for comparison purposes. The most accurate load estimate on the River Bandon is found using a stage separated power curve, while the most accurate load estimate on the River Owenabue is found using a general power curve. Maximum full monthly errors of - 76% to + 63% are found on the River Bandon with errors of - 65% to + 359% found on the River Owenabue. The average monthly error on the River Bandon is - 12% with an average error of + 87% on the River Owenabue. The use of daily flow data in the load estimation process does not result in a significant loss of accuracy on either river. Historic load estimates (with a 95% confidence interval) were hindcast from the flow record and average annual loads of 7253 ± 673 tonnes on the River Bandon and 1935 ± 325 tonnes on the River Owenabue were estimated to be passing the gauging stations.

Analyzing the uncertainty of suspended sediment load prediction using sequential data assimilation

NASA Astrophysics Data System (ADS)

Leisenring, Marc; Moradkhani, Hamid

2012-10-01

SummaryA first step in understanding the impacts of sediment and controlling the sources of sediment is to quantify the mass loading. Since mass loading is the product of flow and concentration, the quantification of loads first requires the quantification of runoff volume. Using the National Weather Service's SNOW-17 and the Sacramento Soil Moisture Accounting (SAC-SMA) models, this study employed particle filter based Bayesian data assimilation methods to predict seasonal snow water equivalent (SWE) and runoff within a small watershed in the Lake Tahoe Basin located in California, USA. A procedure was developed to scale the variance multipliers (a.k.a hyperparameters) for model parameters and predictions based on the accuracy of the mean predictions relative to the ensemble spread. In addition, an online bias correction algorithm based on the lagged average bias was implemented to detect and correct for systematic bias in model forecasts prior to updating with the particle filter. Both of these methods significantly improved the performance of the particle filter without requiring excessively wide prediction bounds. The flow ensemble was linked to a non-linear regression model that was used to predict suspended sediment concentrations (SSCs) based on runoff rate and time of year. Runoff volumes and SSC were then combined to produce an ensemble of suspended sediment load estimates. Annual suspended sediment loads for the 5 years of simulation were finally computed along with 95% prediction intervals that account for uncertainty in both the SSC regression model and flow rate estimates. Understanding the uncertainty associated with annual suspended sediment load predictions is critical for making sound watershed management decisions aimed at maintaining the exceptional clarity of Lake Tahoe. The computational methods developed and applied in this research could assist with similar studies where it is important to quantify the predictive uncertainty of pollutant load estimates.

Suspended-sediment concentrations, loads, total suspended solids, turbidity, and particle-size fractions for selected rivers in Minnesota, 2007 through 2011

USGS Publications Warehouse

Ellison, Christopher A.; Savage, Brett E.; Johnson, Gregory D.

2014-01-01

Sediment-laden rivers and streams pose substantial environmental and economic challenges. Excessive sediment transport in rivers causes problems for flood control, soil conservation, irrigation, aquatic health, and navigation, and transports harmful contaminants like organic chemicals and eutrophication-causing nutrients. In Minnesota, more than 5,800 miles of streams are identified as impaired by the Minnesota Pollution Control Agency (MPCA) due to elevated levels of suspended sediment. The U.S. Geological Survey, in cooperation with the MPCA, established a sediment monitoring network in 2007 and began systematic sampling of suspended-sediment concentrations (SSC), total suspended solids (TSS), and turbidity in rivers across Minnesota to improve the understanding of fluvial sediment transport relations. Suspended-sediment samples collected from 14 sites from 2007 through 2011 indicated that the Zumbro River at Kellogg in the driftless region of southeast Minnesota had the highest mean SSC of 226 milligrams per liter (mg/L) followed by the Minnesota River at Mankato with a mean SSC of 193 mg/L. During the 2011 spring runoff, the single highest SSC of 1,250 mg/L was measured at the Zumbro River. The lowest mean SSC of 21 mg/L was measured at Rice Creek in the northern Minneapolis- St. Paul metropolitan area. Total suspended solids (TSS) have been used as a measure of fluvial sediment by the MPCA since the early 1970s; however, TSS concentrations have been determined to underrepresent the amount of suspended sediment. Because of this, the MPCA was interested in quantifying the differences between SSC and TSS in different parts of the State. Comparisons between concurrently sampled SSC and TSS indicated significant differences at every site, with SSC on average two times larger than TSS concentrations. The largest percent difference between SSC and TSS was measured at the South Branch Buffalo River at Sabin, and the smallest difference was observed at the Des Moines River at Jackson. Regression analysis indicated that 7 out of 14 sites had poor or no relation between SSC and streamflow. Only two sites, the Knife River and the Wild Rice River at Twin Valley, had strong correlations between SSC and streamflow, with coefficient of determination (R2) values of 0.82 and 0.80, respectively. In contrast, turbidity had moderate to strong relations with SSC at 10 of 14 sites and was superior to streamflow for estimating SSC at all sites. These results indicate that turbidity may be beneficial as a surrogate for SSC in many of Minnesota’s rivers. Suspended-sediment loads and annual basin yields indicated that the Minnesota River had the largest average annual sediment load of 1.8 million tons per year and the largest mean annual sediment basin yield of 120 tons of sediment per year per square mile. Annual TSS loads were considerably lower than suspended-sediment loads. Overall, the largest suspended-sediment and TSS loads were transported during spring snowmelt runoff, although loads during the fall and summer seasons occasionally exceeded spring runoff at some sites. This study provided data from which to characterize suspended sediment across Minnesota’s diverse geographical settings. The data analysis improves understanding of sediment transport relations, provides information for improving sediment budgets, and documents baseline data to aid in understanding the effects of future land use/land cover on water quality. Additionally, the data provides insight from which to evaluate the effectiveness and efficiency of best management practices at the watershed scale.

28 CFR 505.2 - Annual determination of average cost of incarceration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... MANAGEMENT AND ADMINISTRATION COST OF INCARCERATION FEE § 505.2 Annual determination of average cost of... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Annual determination of average cost of... average cost of incarceration. This calculation is reviewed annually and the revised figure is published...

Southern Hemisphere Carbon Monoxide Inferannual Variability Observed by Terra/Measurement of Pollution in the Troposphere (MOPITT)

NASA Technical Reports Server (NTRS)

Edwards, D. P.; Petron, G.; Novelli, P. C.; Emmons, L. K.; Gille, J. C.; Drummond, J. R.

2010-01-01

Biomass burning is an annual occurrence in the tropical southern hemisphere (SH) and represents a major source of regional pollution. Vegetation fires emit carbon monoxide (CO), which due to its medium lifetime is an excellent tracer of tropospheric transport. CO is also one of the few tropospheric trace gases currently observed from satellite and this provides long-term global measurements. In this paper, we use the 5 year CO data record from the Measurement Of Pollution In The Troposphere (MOPITT) instrument to examine the inter-annual variability of the SH CO loading and show how this relates to climate conditions which determine the intensity of fire sources. The MOPITT observations show an annual austral springtime peak in the SH zonal CO loading each year with dry-season biomass burning emissions in S. America, southern Africa, the Maritime Continent, and northwestern Australia. Although fires in southern Africa and S. America typically produce the greatest amount of CO, the most significant inter-annual variation is due to varying fire activity and emissions from the Maritime Continent and northern Australia. We find that this variation in turn correlates well with the El Nino Southern Oscillation precipitation index. Between 2000 and 2005, emissions were greatest in late 2002 and an inverse modeling of the MOPITT data using the MOZART chemical transport model estimates the southeast Asia regional fire source for the year August 2002 to September 2003 to be 52 Tg CO. Comparison of the MOPITT retrievals and NOAA surface network measurements indicate that the latter do not fully capture the inter-annual variability or the seasonal range of the CO zonal average concentration due to biases associated with atmospheric and geographic sampling.

The Importance of Asia as a Source of Black Carbon to the Arctic Constrained by Aircraft and Surface Measurements.

NASA Astrophysics Data System (ADS)

Xu, J.; Martin, R.; Morrow, A.; Sharma, S.; Huang, L.; Leaitch, W. R.; Burkart, J.; Schulz, H.; Zanatta, M.; Willis, M. D.; Henze, D. K.; Lee, C. J.; Herber, A. B.; Abbatt, J.

2017-12-01

The contribution of Asian sources to Arctic black carbon (BC) remains uncertain. We interpret a series of recent airborne (NETCARE 2015, PAMARCMiP 2009 and 2011 campaigns) and ground-based measurements (at Alert, Barrow and Ny-Ålesund) from multiple methods (thermal, laser incandescence and light absorption) with the GEOS-Chem global chemical transport model and its adjoint to attribute the sources of Arctic BC. Our simulations with the addition of seasonally varying domestic heating and of gas flaring emissions are consistent with ground-based measurements of BC concentrations at Alert and Barrow to within 13% in winter and spring, and with airborne measurements to within 17 % except for an underestimation in the middle troposphere (500-700 hPa). Sensitivity simulations suggest that anthropogenic emissions from eastern and southern Asia have the largest impact on the Arctic BC column burden both in spring (56 %) and annually (37 %), with the largest contribution in the middle troposphere (400-700 hPa). Anthropogenic emissions from northern Asia are the primary source of the Arctic surface BC ( 40% annually). Our adjoint simulations indicate noteworthy contributions from emissions in eastern China (15 %) and western Siberia (6.5 %) to the Arctic BC loadings on an annual average. Emissions from as south as the Indo-Gangetic Plain have a substantial impact (6.3 % annually) on Arctic BC as well. The Tarim oilfield in western China stands out as the second most influential grid cell with an annual contribution of 2.6 %. Gas flaring emissions from oilfields in western Siberia have a striking impact (13 %) on Arctic BC loadings in January, comparable to the total influence of continental Europe and North America (6.5 % each in January).

Dissolved-Solids Load in Henrys Fork Upstream from the Confluence with Antelope Wash, Wyoming, Water Years 1970-2009

USGS Publications Warehouse

Foster, Katharine; Kenney, Terry A.

2010-01-01

Annual dissolved-solids load at the mouth of Henrys Fork was estimated by using data from U.S. Geological Survey streamflow-gaging station 09229500, Henrys Fork near Manila, Utah. The annual dissolved-solids load for water years 1970-2009 ranged from 18,300 tons in 1977 to 123,300 tons in 1983. Annual streamflows for this period ranged from 14,100 acre-feet in 1977 to 197,500 acre-feet in 1983. The 25-percent trimmed mean dissolved-solids load for water years 1970-2009 was 44,300 tons per year at Henrys Fork near Manila, Utah. Previous simulations using a SPAtially Referenced Regression On Watershed attributes (SPARROW) model for dissolved solids specific to water year 1991 conditions in the Upper Colorado River Basin predicted an annual dissolved-solids load of 25,000 tons for the Henrys Fork Basin upstream from Antelope Wash. On the basis of computed dissolved-solids load data from Henrys Fork near Manila, Utah, together with estimated annual dissolved-solids load from Antelope Wash and Peoples Canal, this prediction was adjusted to 37,200 tons. As determined by simulations with the Upper Colorado River Basin SPARROW model, approximately 56 percent (14,000 tons per year) of the dissolved-solids load at Henrys Fork upstream from Antelope Wash is associated with the 21,500 acres of irrigated agricultural lands in the upper Henrys Fork Basin.

Investigating organic matter in Fanno Creek, Oregon, Part 2 of 3: sources, sinks, and transport of organic matter with fine sediment

USGS Publications Warehouse

Keith, Mackenzie K.; Sobieszczyk, Steven; Goldman, Jami H.; Rounds, Stewart A.

2014-01-01

Organic matter (OM) is abundant in Fanno Creek, Oregon, USA, and has been tied to a variety of water-quality concerns, including periods of low dissolved oxygen downstream in the Tualatin River, Oregon. The key sources of OM in Fanno Creek and other Tualatin River tributaries have not been fully identified, although isotopic analyses from previous studies indicated a predominantly terrestrial source. This study investigates the role of fine sediment erosion and deposition (mechanisms and spatial patterns) in relation to OM transport. Geomorphic mapping within the Fanno Creek floodplain shows that a large portion (approximately 70%) of the banks are eroding or subject to erosion, likely as a result of the imbalance caused by anthropogenic alteration. Field measurements of long- and short-term bank erosion average 4.2 cm/year and average measurements of deposition for the watershed are 4.8 cm/year. The balance between average annual erosion and deposition indicates an export of 3,250 metric tons (tonnes, t) of fine sediment to the Tualatin River—about twice the average annual export of 1,880 t of sediment at a location 2.4 km from the creek’s mouth calculated from suspended sediment load regressions from continuous turbidity data and suspended sediment samples. Carbon content from field samples of bank material, combined with fine sediment export rates, indicates that about 29–67 t of carbon, or about 49–116 t of OM, from bank sediment may be exported to the Tualatin River from Fanno Creek annually, an estimate that is a lower bound because it does not account for the mass wasting of organic-rich O and A soil horizons that enter the stream.

Investigating organic matter in Fanno Creek, Oregon, Part 2 of 3: Sources, sinks, and transport of organic matter with fine sediment

NASA Astrophysics Data System (ADS)

Keith, Mackenzie K.; Sobieszczyk, Steven; Goldman, Jami H.; Rounds, Stewart A.

2014-11-01

Organic matter (OM) is abundant in Fanno Creek, Oregon, USA, and has been tied to a variety of water-quality concerns, including periods of low dissolved oxygen downstream in the Tualatin River, Oregon. The key sources of OM in Fanno Creek and other Tualatin River tributaries have not been fully identified, although isotopic analyses from previous studies indicated a predominantly terrestrial source. This study investigates the role of fine sediment erosion and deposition (mechanisms and spatial patterns) in relation to OM transport. Geomorphic mapping within the Fanno Creek floodplain shows that a large portion (approximately 70%) of the banks are eroding or subject to erosion, likely as a result of the imbalance caused by anthropogenic alteration. Field measurements of long- and short-term bank erosion average 4.2 cm/year and average measurements of deposition for the watershed are 4.8 cm/year. The balance between average annual erosion and deposition indicates an export of 3,250 metric tons (tonnes, t) of fine sediment to the Tualatin River-about twice the average annual export of 1,880 t of sediment at a location 2.4 km from the creek's mouth calculated from suspended sediment load regressions from continuous turbidity data and suspended sediment samples. Carbon content from field samples of bank material, combined with fine sediment export rates, indicates that about 29-67 t of carbon, or about 49-116 t of OM, from bank sediment may be exported to the Tualatin River from Fanno Creek annually, an estimate that is a lower bound because it does not account for the mass wasting of organic-rich O and A soil horizons that enter the stream.

Optimization of 10 kW solar photovoltaic – diesel generator hybrid energy system for different load factors at Jaisalmer location of Rajasthan, India

NASA Astrophysics Data System (ADS)

Saraswat, S. K.; Rao, K. V. S.

2018-03-01

Jaisalmer town in Rajasthan, India is having annual average solar insolation of 5.80 kWh/m2/day and 270 – 300 clear sky days in a year. A 10 kW off-grid hybrid energy system (HES) consisting of solar photovoltaic panels – diesel generator – bidirectional converter and batteries with zero percentage loss of load for Jaisalmer is designed using HOMER (version 3.4.3) software. Different system load factors of 0.33, 0.50, 0.67, 0.83 and 1 corresponding to fraction of running hours per day of the system are considered. The system is analyzed for all three aspects, namely, electrical, economic and emission point of view. Least levelized cost of electricity (LCOE) of Rs. 8.43/kWh is obtained at a load factor value of 0.5. If diesel generator alone (without Solar PV) is used to fulfil the demand for a load factor of 0.5the value of LCOE is obtained Rs.19.23/kWh. Comparison of results obtained for HES and diesel generator are made for load factor of 0.5 and 1.

Nontidal Loading Applied in VLBI Geodetic Analysis

NASA Astrophysics Data System (ADS)

MacMillan, D. S.

2015-12-01

We investigate the application of nontidal atmosphere pressure, hydrology, and ocean loading series in the analysis of VLBI data. The annual amplitude of VLBI scale variation is reduced to less than 0.1 ppb, a result of the annual components of the vertical loading series. VLBI site vertical scatter and baseline length scatter is reduced when these loading models are applied. We operate nontidal loading services for hydrology loading (GLDAS model), atmospheric pressure loading (NCEP), and nontidal ocean loading (JPL ECCO model). As an alternative validation, we compare these loading series with corresponding series generated by other analysis centers.

Estimated nitrogen loads from selected tributaries in Connecticut draining to Long Island Sound, 1999–2009

USGS Publications Warehouse

Mullaney, John R.; Schwarz, Gregory E.

2013-01-01

The total nitrogen load to Long Island Sound from Connecticut and contributing areas to the north was estimated for October 1998 to September 2009. Discrete measurements of total nitrogen concentrations and continuous flow data from 37 water-quality monitoring stations in the Long Island Sound watershed were used to compute total annual nitrogen yields and loads. Total annual computed yields and basin characteristics were used to develop a generalized-least squares regression model for use in estimating the total nitrogen yields from unmonitored areas in coastal and central Connecticut. Significant variables in the regression included the percentage of developed land, percentage of row crops, point-source nitrogen yields from wastewater-treatment facilities, and annual mean streamflow. Computed annual median total nitrogen yields at individual monitoring stations ranged from less than 2,000 pounds per square mile in mostly forested basins (typically less than 10 percent developed land) to more than 13,000 pounds per square mile in urban basins (greater than 40 percent developed) with wastewater-treatment facilities and in one agricultural basin. Medians of computed total annual nitrogen yields for water years 1999–2009 at most stations were similar to those previously computed for water years 1988–98. However, computed medians of annual yields at several stations, including the Naugatuck River, Quinnipiac River, and Hockanum River, were lower than during 1988–98. Nitrogen yields estimated for 26 unmonitored areas downstream from monitoring stations ranged from less than 2,000 pounds per square mile to 34,000 pounds per square mile. Computed annual total nitrogen loads at the farthest downstream monitoring stations were combined with the corresponding estimates for the downstream unmonitored areas for a combined estimate of the total nitrogen load from the entire study area. Resulting combined total nitrogen loads ranged from 38 to 68 million pounds per year during water years 1999–2009. Total annual loads from the monitored basins represent 63 to 74 percent of the total load. Computed annual nitrogen loads from four stations near the Massachusetts border with Connecticut represent 52 to 54 percent of the total nitrogen load during water years 2008–9, the only years with data for all the border sites. During the latter part of the 1999–2009 study period, total nitrogen loads to Long Island Sound from the study area appeared to increase slightly. The apparent increase in loads may be due to higher than normal streamflows, which consequently increased nonpoint nitrogen loads during the study, offsetting major reductions of nitrogen from wastewater-treatment facilities. Nitrogen loads from wastewater treatment facilities declined as much as 2.3 million pounds per year in areas of Connecticut upstream from the monitoring stations and as much as 5.8 million pounds per year in unmonitored areas downstream in coastal and central Connecticut.

Characteristics of sediment data and annual suspended-sediment loads and yields for selected lower Missouri River mainstem and tributary stations, 1976-2008

USGS Publications Warehouse

Heimann, David C.; Rasmussen, Patrick P.; Cline, Teri L.; Pigue, Lori M.; Wagner, Holly R.

2010-01-01

Suspended-sediment data from 18 selected surface-water monitoring stations in the lower Missouri River Basin downstream from Gavins Point Dam were used in the computation of annual suspended-sediment and suspended-sand loads for 1976 through 2008. Three methods of suspended-sediment load determination were utilized and these included the subdivision method, regression of instantaneous turbidity with suspended-sediment concentrations at selected stations, and regression techniques using the Load Estimator (LOADEST) software. Characteristics of the suspended-sediment and streamflow data collected at the 18 monitoring stations and the tabulated annual suspended-sediment and suspended-sand loads and yields are presented.

50 CFR 216.242 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

...-headed whale (Peponocephala electra)—8270 (an average of 1654 annually). (Q) Pygmy killer whale (Feresa attenuata)—1400 (an average of 280 annually). (R) False killer whale (Pseudorca crassidens)—2690 (an average of 538 annually). (S) Killer whale (Orcinus orca)—2515 (an average of 503 annually). (T) Pilot whales...

50 CFR 216.242 - Permissible methods of taking.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-headed whale (Peponocephala electra)—8270 (an average of 1654 annually). (Q) Pygmy killer whale (Feresa attenuata)—1400 (an average of 280 annually). (R) False killer whale (Pseudorca crassidens)—2690 (an average of 538 annually). (S) Killer whale (Orcinus orca)—2515 (an average of 503 annually). (T) Pilot whales...

40 CFR 80.205 - How is the annual refinery or importer average and corporate pool average sulfur level determined?

Code of Federal Regulations, 2010 CFR

2010-07-01

... average and corporate pool average sulfur level determined? 80.205 Section 80.205 Protection of... ADDITIVES Gasoline Sulfur Gasoline Sulfur Standards § 80.205 How is the annual refinery or importer average and corporate pool average sulfur level determined? (a) The annual refinery or importer average and...

40 CFR 80.205 - How is the annual refinery or importer average and corporate pool average sulfur level determined?

Code of Federal Regulations, 2011 CFR

2011-07-01

... average and corporate pool average sulfur level determined? 80.205 Section 80.205 Protection of... ADDITIVES Gasoline Sulfur Gasoline Sulfur Standards § 80.205 How is the annual refinery or importer average and corporate pool average sulfur level determined? (a) The annual refinery or importer average and...

40 CFR 80.205 - How is the annual refinery or importer average and corporate pool average sulfur level determined?

Code of Federal Regulations, 2013 CFR

2013-07-01

... average and corporate pool average sulfur level determined? 80.205 Section 80.205 Protection of... ADDITIVES Gasoline Sulfur Gasoline Sulfur Standards § 80.205 How is the annual refinery or importer average and corporate pool average sulfur level determined? (a) The annual refinery or importer average and...

40 CFR 80.205 - How is the annual refinery or importer average and corporate pool average sulfur level determined?

Code of Federal Regulations, 2014 CFR

2014-07-01

... average and corporate pool average sulfur level determined? 80.205 Section 80.205 Protection of... ADDITIVES Gasoline Sulfur Gasoline Sulfur Standards § 80.205 How is the annual refinery or importer average and corporate pool average sulfur level determined? (a) The annual refinery or importer average and...

A VVWBO-BVO-based GM (1,1) and its parameter optimization by GRA-IGSA integration algorithm for annual power load forecasting

PubMed Central

Wang, Hongguang

2018-01-01

Annual power load forecasting is not only the premise of formulating reasonable macro power planning, but also an important guarantee for the safety and economic operation of power system. In view of the characteristics of annual power load forecasting, the grey model of GM (1,1) are widely applied. Introducing buffer operator into GM (1,1) to pre-process the historical annual power load data is an approach to improve the forecasting accuracy. To solve the problem of nonadjustable action intensity of traditional weakening buffer operator, variable-weight weakening buffer operator (VWWBO) and background value optimization (BVO) are used to dynamically pre-process the historical annual power load data and a VWWBO-BVO-based GM (1,1) is proposed. To find the optimal value of variable-weight buffer coefficient and background value weight generating coefficient of the proposed model, grey relational analysis (GRA) and improved gravitational search algorithm (IGSA) are integrated and a GRA-IGSA integration algorithm is constructed aiming to maximize the grey relativity between simulating value sequence and actual value sequence. By the adjustable action intensity of buffer operator, the proposed model optimized by GRA-IGSA integration algorithm can obtain a better forecasting accuracy which is demonstrated by the case studies and can provide an optimized solution for annual power load forecasting. PMID:29768450

Water-quality characteristics of urban runoff and estimates of annual loads in the Tampa Bay area, Florida, 1975-80

USGS Publications Warehouse

Lopez, M.A.; Giovannelli, R.F.

1984-01-01

Rainfall, runoff, and water quality data were collected at nine urban watersheds in the Tampa Bay area from 1975 to 1980. Watershed drainage area ranged from 0.34 to 0.45 sq mi. Land use was mixed. Development ranged from a mostly residential watershed with a 19% impervious surface, to a commercial-residential watershed with a 61% impervious surface. Average biochemical oxygen demand concentrations of base flow at two sites and of stormwater runoff at five sites exceeded treated sewage effluent standards. Average coliform concentrations of stormwater runoff at all sites were several orders of magnitude greater than standards for Florida Class III receiving water (for recreation or propagation and management of fish and wildlife). Average concentrations of lead and zinc in stormwater runoff were consistently higher than Class III standards. Stormwater-runoff loads and base-flow concentrations of biochemical oxygen demand, chemical oxygen demand, total nitrogen, total organic nitrogen, total phosphorus, and lead were related to runoff volume, land use, urban development, and antecedent daily rainfall by multiple linear regression. Stormwater-runoff volume was related to pervious area, hydraulically connected impervious surfaces, storm rainfall, and soil-infiltration index. Base-flow daily discharge was related to drainage area and antecedent daily rainfall. The flow regression equations of this report were used to compute 1979 water-year loads of biochemical oxygen demand, chemical oxygen demand, total nitrogen, total organic nitrogen, total phosphorus , and total lead for the nine Tampa Bay area urban watersheds. (Lantz-PTT)

Functional relationships between vegetation, channel morphology, and flow efficiency in an alluvial (anabranching) river

NASA Astrophysics Data System (ADS)

Jansen, John D.; Nanson, Gerald C.

2010-12-01

Water and sediment flux interactions are examined in Magela Creek, an alluvial (anabranching) sand bed river in the northern Australian tropics. Dense riparian vegetation stabilizes the channels and floodplains thereby preventing erosional instability at flow depths up to 6.2 times bankfull and discharges up to 15 times bankfull. Narrow anabranching channels characterize >92% of the alluvial reach and transport bed load more efficiently than short reaches of wide single-channels, yet overall 29 ± 12% of the bed load is sequestered and the average vertical accretion rate is 0.41 ± 0.17 mm yr-1 along the 12 km study reach. The most effective discharge for transporting sediment (40-45 m3 s-1) is consistent at all 5 stations (10 channels) examined and is equivalent to the channel-forming discharge. It has an average recurrence interval of 1.01 years, occurs for an exceptionally long portion (13-15%) of the annual flow duration, and averages a remarkable 2.1 times bankfull. The high flow efficiency (i.e., bed load transport rate to stream power ratio) of the anabranches is facilitated by low width/depth channels with banks reinforced by vegetation. Colonnades of bank top trees confine high-velocity flows overbed (i.e., over the channel bed) at stages well above bankfull. At even larger overbank flows, momentum exchange between the channels and forested floodplains restrains overbed velocities, in some cases causing them to decline, thereby limiting erosion. Magela Creek exhibits a complicated set of planform, cross-sectional and vegetative adjustments that boost overbed velocities and enhance bed load yield in multiple channels while restraining velocities and erosion at the largest discharges.

Surface water pollution in three urban territories of Nepal, India, and Bangladesh.

PubMed

Karn, S K; Harada, H

2001-10-01

In South Asian countries such as Nepal, India, and Bangladesh, pollution of rivers is more severe and critical near urban stretches due to huge amounts of pollution load discharged by urban activities. The Bagmati River in the Kathmandu valley, the Yamuna River at Delhi, and peripheral rivers (mainly Buriganga River) of Dhaka suffer from severe pollution these days. The observed dry season average of biochemical oxygen demand (BOD) in all these rivers is in the range of 20-30 mg/liter and total coliform are as high as 104-105 MPN/100 ml. Per capita pollution load discharge of urban areas has been estimated to be about 31, 19, and 25 g BOD/capita/day in Bagmati, Yamuna, and the rivers of Dhaka, respectively. Regression analysis reveals pollution loads steadily increasing nearly in step with the trend in urbanization. The dissolved oxygen (DO) level of the Bagmati and Buriganga rivers is declining at an average annual rate of nearly 0.3 mg/liter/year. Unplanned urbanization and industrialization occurring in these cities may be largely responsible for this grave situation. Inadequate sewerage, on-site sanitation, and wastewater treatment facilities in one hand, and lack of effective pollution control measures and their strict enforcement on the other are the major causes of rampant discharge of pollutants in the aquatic systems.

Changes in phosphorus concentrations and loads in the Assabet River, Massachusetts, October 2008 through April 2014

USGS Publications Warehouse

Savoie, Jennifer G.; DeSimone, Leslie A.; Mullaney, John R.; Zimmerman, Marc J.; Waldron, Marcus C.

2016-10-24

Treated effluent discharged from municipal wastewater-treatment plants to the Assabet River in central Massachusetts includes phosphorus, which leads to increased growth of nuisance aquatic plants that decrease the river’s water quality and aesthetics in impounded reaches during the growing season. To improve the river’s water quality and aesthetics, the U.S. Environmental Protection Agency approved a total maximum daily load for phosphorus in 2004 that directed the wastewater-treatment plants to reduce the amount of total phosphorus discharged to the river by 2012. The permitted total phosphorus monthly average of 0.75 milligrams per liter during the aquatic plant growing season (April 1 through October 31) was reduced by the total maximum daily load to a target of 0.1 milligrams per liter by 2012, and the nongrowing-season limit was unchanged at 1.0 milligrams per liter.From October 2008 through April 2014, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, measured streamflow and collected weekly flow-proportional, composite samples of water from the Assabet River for analysis of concentrations of total phosphorus and orthophosphate. Streamflow and concentration data were used to estimate total phosphorus and orthophosphate loads in the river. The purpose of this monitoring effort was to evaluate phosphorus concentrations and loads in the river before, during, and after the wastewater-treatment-plant upgrades and to assess the effects of seasonal differences in permitted discharges. The locations of water-quality-monitoring stations, with respect to the Hudson and Ben Smith impoundments, enabled examination of effects of phosphorus entering and leaving the impoundments.Annual median concentrations of total phosphorus in wastewater-treatment plants were reduced by more than 80 percent with the plant upgrades. Measured instream annual median concentrations of total phosphorus in the Assabet River decreased by about 38 to 50 percent at three of the four monitoring stations following the wastewater-treatment-plant upgrades. At the station farthest upstream, the median total phosphorus concentration remained unchanged throughout the study; this may be attributed to the site location and potential resuspension of particulate organic matter during periods of increased streamflow. Annual median loads from the wastewater-treatment plants were reduced by up to 91 percent following the upgrades, instream annual median total phosphorus loads at the three downstream stations decreased by 71 to 76 percent, and instream orthophosphate loads at the three downstream stations decreased by 79 to 87 percent.Seasonal fluctuations (growing versus nongrowing) of total phosphorus and orthophosphate were observed instream before the upgrades. However, after the upgrades, fluctuations in phosphorus released from the treatment plants were slight and seasonal changes were typically not observed instream.Annual loads entering and leaving the two impoundments were inconclusive in determining whether the impoundments were sources or sinks of total phosphorus during the study. Total phosphorus loads entering the Hudson impoundment were consistently greater than those leaving; however, there was uncertainty about the loads at the monitoring station upstream from this impoundment. At the Ben Smith impoundment, total phosphorus and orthophosphate loads downstream were slightly greater than those upstream from the impoundment, but the differences may reflect additions from tributaries and overland runoff.Estimated instream total phosphorus concentrations and loads indicated that the decreases in total phosphorus in wastewater-treatment-plant discharges were accompanied by reductions measured in the Assabet River. A statistical analysis which incorporates the effect of varying flow conditions demonstrated significant reductions in total phosphorus concentrations after the wastewater-treatment-plant upgrades at three of the four instream monitoring stations. No significant change was observed at the most upstream location, the Assabet River at Port Street at Hudson, Massachusetts (station number 01096835), which may have been affected by flow-related resuspension of particulate phosphorus.

Fluvial response to climate variations and anthropogenic perturbations for the Ebro River, Spain in the last 4,000 years.

PubMed

Xing, Fei; Kettner, Albert J; Ashton, Andrew; Giosan, Liviu; Ibáñez, Carles; Kaplan, Jed O

2014-03-01

Fluvial sediment discharge can vary in response to climate changes and human activities, which in return influences human settlements and ecosystems through coastline progradation and retreat. To understand the mechanisms controlling the variations of fluvial water and sediment discharge for the Ebro drainage basin, Spain, we apply a hydrological model HydroTrend. Comparison of model results with a 47-year observational record (AD 1953-1999) suggests that the model adequately captures annual average water discharge (simulated 408 m(3)s(-1) versus observed 425 m(3)s(-1)) and sediment load (simulated 0.3 Mt yr(-1) versus observed 0.28 ± 0.04 Mt yr(-1)) for the Ebro basin. A long-term (4000-year) simulation, driven by paleoclimate and anthropogenic land cover change scenarios, indicates that water discharge is controlled by the changes in precipitation, which has a high annual variability but no long-term trend. Modeled suspended sediment load, however, has an increasing trend over time, which is closely related to anthropogenic land cover variations with no significant correlation to climatic changes. The simulation suggests that 4,000 years ago the annual sediment load to the ocean was 30.5 Mt yr(-1), which increased over time to 47.2 Mt yr(-1) (AD 1860-1960). In the second half of the 20th century, the emplacement of large dams resulted in a dramatic decrease in suspended sediment discharge, eventually reducing the flux to the ocean by more than 99% (mean value changes from 38.1 Mt yr(-1) to 0.3 Mt yr(-1)). Copyright © 2013 Elsevier B.V. All rights reserved.

Modeling Horizontal GPS Seasonal Signals Caused by Ocean Loading

NASA Astrophysics Data System (ADS)

Bartlow, N. M.; Fialko, Y. A.

2014-12-01

GPS monuments around the world exhibit seasonal signals in both the horizontal and vertical components with amplitudes on the order of centimeters. For analysis of tectonic signals, researchers typically fit and remove a sine wave with an annual period, and sometimes an additional sine wave with a semiannual period. As interest grows in analyzing smaller, slower signals it becomes more important to correct for these seasonal signals accurately. It is well established that the vertical component of seasonal GPS signals is largely due to continental water storage cycles (e.g. van Dam et al., GRL, 2001). Horizontal seasonal signals however are not well explained by continental water storage. We examine horizontal seasonal signals across western North America and find that the horizontal component is coherent at very large spatial scales and is in general oriented perpendicular to the nearest coastline, indicating an oceanic origin. Additionally, horizontal and vertical annual signals are out of phase by approximately 2 months indicating different physical origins. Studies of GRACE and ocean bottom pressure data indicate an annual variation of non-steric, non-tidal ocean height with an average amplitude of 1 cm globally (e.g. Ponte et al., GRL, 2007). We use Some Programs for Ocean Tide Loading (SPOTL; Agnew, SIO Technical Report, 2012) to model predicted displacements due to these (non-tidal) ocean loads and find general agreement with observed horizontal GPS seasonal signals. In the future, this may lead to a more accurate way to predict and remove the seasonal component of GPS displacement time-series, leading to better discrimination of the true tectonic signal. Modeling this long wavelength signal also provides a potential opportunity to probe the structure of the Earth.

Modeling sustainable reuse of nitrogen-laden wastewater by poplar.

PubMed

Wang, Yusong; Licht, Louis; Just, Craig

2016-01-01

Numerical modeling was used to simulate the leaching of nitrogen (N) to groundwater as a consequence of irrigating food processing wastewater onto grass and poplar under various management scenarios. Under current management practices for a large food processor, a simulated annual N loading of 540 kg ha(-1) yielded 93 kg ha(-1) of N leaching for grass and no N leaching for poplar during the growing season. Increasing the annual growing season N loading to approximately 1,550 kg ha(-1) for poplar only, using "weekly", "daily" and "calculated" irrigation scenarios, yielded N leaching of 17 kg ha(-1), 6 kg ha(-1), and 4 kg ha(-1), respectively. Constraining the simulated irrigation schedule by the current onsite wastewater storage capacity of approximately 757 megaliters (Ml) yielded N leaching of 146 kg ha(-1) yr(-1) while storage capacity scenarios of 3,024 and 4,536 Ml yielded N leaching of 65 and 13 kg ha(-1) yr(-1), respectively, for a loading of 1,550 kg ha(-1) yr(-1). Further constraining the model by the current wastewater storage volume and the available land area (approximately 1,000 hectares) required a "diverse" irrigation schedule that was predicted to leach a weighted average of 13 kg-N ha(-1) yr(-1) when dosed with 1,063 kg-N ha(-1) yr(-1).

Residential energy use and potential conservation through reduced laundering temperatures in the United States and Canada.

PubMed

Sabaliunas, Darius; Pittinger, Charles; Kessel, Cristy; Masscheleyn, Patrick

2006-04-01

A residential energy-use model was developed to estimate energy budgets for household laundering practices in the United States and Canada. The thermal energy for heating water and mechanical energy for agitating clothes in conventional washing machines were calculated for representative households in the United States and Canada. Comparisons in energy consumption among hot-, warm-, and cold-water wash and rinse cycles, horizontal- and vertical-axis washing machines, and gas and electric water heaters, were calculated on a per-wash-load basis. Demographic data for current laundering practices in the United States and Canada were then incorporated to estimate household and national energy consumption on an annual basis for each country. On average, the thermal energy required to heat water using either gas or electric energy constitutes 80% to 85% of the total energy consumed per wash in conventional, vertical-axis (top-loading) washing machines. The balance of energy used is mechanical energy. Consequently, the potential energy savings per load in converting from hot-and-warm- to cold-wash temperatures can be significant. Annual potential energy and cost savings and reductions in carbon dioxide emissions are also estimated for each country, assuming full conversion to cold-wash water temperatures. This study provides useful information to consumers for conserving energy in the home, as well as to, manufacturers in the design of more energy-efficient laundry formulations and appliances.

Occurrence and distribution of dissolved solids, selenium, and uranium in groundwater and surface water in the Arkansas River Basin from the headwaters to Coolidge, Kansas, 1970-2009

USGS Publications Warehouse

Miller, Lisa D.; Watts, Kenneth R.; Ortiz, Roderick F.; ,

2010-01-01

In 2007, the U.S. Geological Survey (USGS), in cooperation with City of Aurora, Colorado Springs Utilities, Colorado Water Conservation Board, Lower Arkansas Valley Water Conservancy District, Pueblo Board of Water Works, Southeastern Colorado Water Activity Enterprise, Southeastern Colorado Water Conservancy District, and Upper Arkansas Water Conservancy District began a retrospective evaluation to characterize the occurrence and distribution of dissolved-solids (DS), selenium, and uranium concentrations in groundwater and surface water in the Arkansas River Basin based on available water-quality data collected by several agencies. This report summarizes and characterizes available DS, dissolved-selenium, and dissolved-uranium concentrations in groundwater and surface water for 1970-2009 and describes DS, dissolved-selenium, and dissolved-uranium loads in surface water along the main-stem Arkansas River and selected tributary and diversion sites from the headwaters near Leadville, Colorado, to the USGS 07137500 Arkansas River near Coolidge, Kansas (Ark Coolidge), streamgage, a drainage area of 25,410 square miles. Dissolved-solids concentrations varied spatially in groundwater and surface water in the Arkansas River Basin. Dissolved-solids concentrations in groundwater from Quaternary alluvial, glacial drift, and wind-laid deposits (HSU 1) increased downgradient with median values of about 220 mg/L in the Upper Arkansas subbasin (Arkansas River Basin from the headwaters to Pueblo Reservoir) to about 3,400 mg/L in the Lower Arkansas subbasin (Arkansas River Basin from John Martin Reservoir to Ark Coolidge). Dissolved-solids concentrations in the Arkansas River also increased substantially in the downstream direction between the USGS 07086000 Arkansas River at Granite, Colorado (Ark Granite), and Ark Coolidge streamgages. Based on periodic data collected from 1976-2007, median DS concentrations in the Arkansas River ranged from about 64 mg/L at Ark Granite to about 4,060 mg/L at Ark Coolidge representing over a 6,000 percent increase in median DS concentrations. Temporal variations in specific conductance values (which are directly related to DS concentrations) and seasonal variations in DS concentrations and loads were investigated at selected sites in the Arkansas River from Ark Granite to Ark Coolidge. Analyses indicated that, for the most part, specific conductance values (surrogate for DS concentrations) have remained relatively constant or have decreased in the Arkansas River since about 1970. Dissolved-solids concentrations in the Arkansas River were higher during the nonirrigation season (November-February) than during the irrigation season (March-October). Average annual DS loads, however, were higher during the irrigation season than during the nonirrigation season. Average annual DS loads during the irrigation season were at least two times and as much as 23 times higher than average annual DS loads during the nonirrigation season with the largest differences occurring at sites located downstream from the two main-stem reservoirs at USGS 07099400 Arkansas River above Pueblo, Colorado (Ark Pueblo), (which is below Pueblo Reservoir) and USGS 07130500 Arkansas River below John Martin Reservoir, Colorado (Ark below JMR). View report for unabridged abstract.

Amazon River investigations, reconnaissance measurements of July 1963

USGS Publications Warehouse

Oltman, Roy Edwin; Sternberg, H. O'R.; Ames, F.C.; Davis, L.C.

1964-01-01

The first measurements of the flow of the Amazon River were made in July 1963 as a joint project of the University of Brazil, the Brazilian Navy, and the U.S. Geological Survey. The discharge of the Amazon River at Obidos was 7,640,000 cfs at an annual flood stage somewhat lower than the average. For comparison the maximum known discharge of the Mississippi River at Vicksburg is about 2,300,000 cfs. Dissolved-solids concentrations and sediment loads of the Amazon River and of several major tributaries were found to be low.

Water resources of Monroe County, New York, water years 1997-99, with emphasis on water quality in the Irondequoit Creek basin—Atmospheric deposition, ground water, streamflow, trends in water quality, and chemical loads to Irondequoit Bay

USGS Publications Warehouse

Sherwood, Donald A.

2003-01-01

Irondequoit Creek drains 169 square miles in the eastern part of Monroe County. Over time, nutrients transported by Irondequoit Creek to Irondequoit Bay on Lake Ontario have contributed to the eutrophication of the bay. Sewage-treatment-plant effluent, a major source of nutrients to the creek and its tributaries, was eliminated from the basin in 1979 by diversion to a regional wastewater-treatment facility, but sediment and contaminants from nonpoint sources continue to enter the creek and Irondequoit Bay.This report, the fourth in a series of reports that present interpretive analyses of the hydrologic data collected in Monroe County since 1984, interprets data from four surface-water monitoring sites in the Irondequoit Creek basin—Irondequoit Creek at Railroad Mills, East Branch Allen Creek at Pittsford, Allen Creek near Rochester, and Irondequoit Creek at Blossom Road. It also interprets data from three sites in the the Genesee River basin—Oatka Creek at Garbutt, Honeoye Creek at Honeoye Falls, and Black Creek at Churchville—as well as the Genesee River at Charlotte Pump Station, and also from a site on Northrup Creek at North Greece. The Northrup Creek site drains a 23.5-square-mile basin in western Monroe County, and provides information on surface-water quality in streams west of the Genesee River and on loads of nutrients delivered to Long Pond, a small eutrophic embayment of Lake Ontario. The report also includes water-level and water-quality data from nine observation wells in Ellison Park, and atmospheric-deposition data from a collection site at Mendon Ponds County Park.Average annual loads of some chemical constituents in atmospheric deposition for 1997–99 differed considerably from those for the long-term period 1984–96. Ammonia and potassium loads for 1997-99 were 144 and 118 percent greater, respectively, than for the previous period. Sodium and ammonia + organic nitrogen loads were 87 and 60 percent greater, respectively. Average annual loads of sulfate and orthophosphate for 1997-99 were 36 and 30 percent lower, respectively, than for the previous period.Loads of all nutrients deposited on the Irondequoit basin from atmospheric sources during 1997–99 greatly exceeded those transported by Irondequoit Creek. The ammonia load deposited on the basin was 139 times the load transported at Blossom Road (the most downstream site); the ammonia + organic nitrogen load was 6.3 times greater, orthophosphate 7.5 times greater, total phosphorus 1.3 times greater and nitrite + nitrate 1.5 times greater. Average yields of dissolved chloride and dissolved sulfate from atmospheric sources were much smaller than those transported by streamflow at Blossom Road.chloride was about 2 percent and sulfate about 8 percent of the amount transported.Trends in concentration of chemical constituents in surface water generally can be attributed to changes in land use, annual and seasonal variations in streamflow, and annual variations in the application of road salt to county highways and roads.Concentrations of several constituents in streams of the Irondequoit Creek basin showed statistically significant (α=0.05) trends from the beginning of their period of record through 1999. The constituent with the greatest number of significant trends was ammonia + organic nitrogen, with downward trends ranging from 4.1 to 5.6 percent per year at Allen Creek, Irondequoit Creek at Blossom Road, and East Branch Allen Creek. Orthophosphate showed an upward trend of 4.1 percent per year at Irondequoit Creek at Railroad Mills (the most upstream site). Dissolved chloride showed upward trends at Railroad Mills, Allen Creek, and Blossom Road. No trends in volatile suspended solids were noted at any of the four Irondequoit basin sites.Northrup Creek showed significant downward trends in concentrations of ammonia + organic nitrogen (3.3 percent per year), total phosphorus (3.4 percent per year), and orthophosphate (5.5 percent per year), and an upward trend for dissolved sulfate (1.8 percent per year). The Genesee River at Charlotte Pump Station showed downward trends of 6.1 percent per year for ammonia + organic nitrogen and 0.1 percent per year for chloride, and upward trends of 1.7 percent per year for total phosphorus and 6.6 percent per year for orthophosphate.Mean annual yields (mass per unit area) of most constituents at the Irondequoit Creek basin sites were similar to those noted for the previous report period (1994–96). East Branch Allen Creek showed lower yields of all constituents during 1997–99 than previously, even though runoff during 1997–99 was greater. These lower yields are attributed to the construction of an upstream detention basin on East Branch Allen Creek in 1995.Statistical analysis of long-term (greater than 12 years) streamflow records for unregulated streams in Monroe County indicated that annual mean flows for water years 1997–99 were in the normal range (75th to 25th percentile), although Allen Creek continues to show a significant downward trend in mean monthly streamflow during the 1984–99 water years.

Analysis of Dissolved Selenium Loading for Selected Sites in the Lower Gunnison River Basin, Colorado, 1978-2005

USGS Publications Warehouse

Thomas, Judith C.; Leib, Kenneth J.; Mayo, John W.

2008-01-01

Elevated selenium concentrations in streams are a water-quality concern in western Colorado. The U.S. Geologic Survey, in cooperation with the Colorado Department of Public Health and Environment, summarized selenium loading in the Lower Gunnison River Basin to support the development of total maximum daily selenium loads at sites that represent the cumulative contribution to U.S. Environmental Protection Agency 303(d) list segments. Analysis of selenium loading included quantifying loads and determining the amount of load that would need to be reduced to bring the site into compliance, referred to as 'the load reduction,' with the State chronic aquatic-life standard for dissolved selenium [85th percentile selenium concentration not to exceed 4.6 ?g/L (micrograms per liter)], referred to as 'the water-quality standard.' Streamflow and selenium concentration data for 54 historical water-quality/water-quantity monitoring sites were compiled from U.S. Geological Survey and Colorado Department of Public Health and Environment data sources. Three methods were used for analysis of selenium concentration data to address the variable data density among sites. Mean annual selenium loads were determined for only 10 of the 54 sites due to data availability limitations. Twenty-two sites had 85th percentile selenium concentrations that exceeded the water-quality standard, 3 sites had 85th percentile selenium concentrations less than the State standard, and 29 sites could not be evaluated with respect to 85th percentile selenium concentration (sample count less than 5). To bring selenium concentrations into compliance with the water-quality standard, more than 80 percent of the mean annual selenium load would need to be reduced at Red Rock Canyon, Dry Cedar Creek, Cedar Creek, Loutzenhizer Arroyo, Sunflower Drain, and Whitewater Creek. More than 50 percent of the mean annual load would need to be reduced at Dry Creek to bring the site into compliance with the water-quality standard. The Uncompahgre River, Gunnison River at Delta, and Gunnison River near Grand Junction would require 69, 34 and 53 percent, respectively, of the mean annual load to be reduced for water years 2001 through 2005 to meet the water-quality standard. Mean annual load reductions can be further reduced by targeting the periods of time when selenium would be removed from streams by remediation. During a previous study of selenium loads in the Lower Gunnison River Basin, mean annual load reductions were estimated at the Gunnison River near Grand Junction for the 1997?2001 study period. Mean annual load reductions estimated for this study period were less than those estimated for the 2001?05 study period, emphasizing the importance of understanding that different study periods can result in different load reduction estimates.

Environmental impact of irrigation in la violada district (Spain): I. Salt export patterns.

PubMed

Isidoro, D; Quílez, D; Aragüés, R

2006-01-01

Salt loading in irrigation return flows contributes to the salinization of the receiving water bodies, particularly when originated in salt-affected areas as frequently found in the middle Ebro River basin (Spain). We determined the salt loading in La Violada Gully from the total dissolved solids (TDS) and flows (Q) during the 1995 to 1998 hydrological years. Since this gully collects flows from various sources, an end-member mixing analysis (EMMA) was performed to quantify the drainage flow from La Violada Irrigation District (VID). Three flow components were identified in La Violada Gully: drainage waters from VID (Qd); tail-waters from irrigation ditches, spill-over, and seepage from the Monegros Canal (Qo); and ground water inflows (Qg) originating in the dryland watershed. Gypsum in the soils of VID was the main source for salts in La Violada Gully (flow-weighted mean TDS=1720 mg L-1, dominated by sulfate and calcium). The contribution of Qg to the total gully flow during the 1996 irrigation season was low (6.5% of the total flow). The 1995 to 1998 annual salt load average in La Violada Gully was 78 628 Mg, 71% of which was exported during the irrigation season. The 1995 to 1998 irrigation season salt load average in Qd was 43 015 Mg (77% of the total load). Thus, irrigated agriculture in VID was the main source of salt loading in this gully, with a yield of 11.1 Mg of salts per hectare of irrigated land for the irrigation season. Efficient irrigation systems and irrigation management practices that reduce Qd are key factors for controlling off-site salt pollution of these gypsum-rich irrigated areas.

20 CFR 30.805 - What evidence does OWCP use to determine a covered Part E employee's average annual wage and...

Code of Federal Regulations, 2010 CFR

2010-04-01

... covered Part E employee's average annual wage and whether he or she experienced compensable wage-loss... OWCP use to determine a covered Part E employee's average annual wage and whether he or she experienced... the Social Security Administration to establish a covered Part E employee's presumed average annual...

20 CFR 30.805 - What evidence does OWCP use to determine a covered Part E employee's average annual wage and...

Code of Federal Regulations, 2011 CFR

2011-04-01

... covered Part E employee's average annual wage and whether he or she experienced compensable wage-loss... OWCP use to determine a covered Part E employee's average annual wage and whether he or she experienced... the Social Security Administration to establish a covered Part E employee's presumed average annual...

Monitoring urban impacts on suspended sediment, trace element, and nutrient fluxes within the City of Atlanta, Georgia, USA: Program design, methodological considerations, and initial results

USGS Publications Warehouse

Horowitz, A.J.; Elrick, K.A.; Smith, J.J.

2008-01-01

Atlanta, Georgia (City of Atlanta, COA), is one of the most rapidly growing urban areas in the US. Beginning in 2003, the US Geological Survey established a long-term water-quantity/quality monitoring network for the COA. The results obtained during the first 2 years have provided insights into the requirements needed to determine the extent of urban impacts on water quality, especially in terms of estimating the annual fluxes of suspended sediment, trace/major elements, and nutrients. During 2004/2005, suspended sediment fluxes from the City of Atlanta (COA) amounted to about 150 000 t year-1; ??? 94% of the transport occurred in conjunction with storm-flow, which also accounted for ??? 65% of the annual discharge. Typically, storm-flow averaged ??? 20% of theyear. Normally, annual suspended sediment fluxes are determined by summing daily loads based on a single calculation step using mean-daily discharge and a single rating curve-derived suspended sediment concentration. Due to the small and 'flashy' nature of the COAs streams, this approach could produce underestimates ranging from 25% to 64%. Accurate estimates (?? 15%) require calculation time-steps as short as every 2-3 h. Based on annual median base-flow/storm-flow chemical concentrations, the annual fluxes of ??? 75% of trace elements (e.g. Cu, Pb, Zn), major elements (e.g. Fe, Al), and total P occur in association with suspended sediment; in turn, ??? 90% of the transport of these constituents occur in conjunction with storm-flow. As such, base-flow sediment-associated and dissolved contributions represent relatively insignificant portions of the total annual load. An exception is total N, whose sediment-associated fluxes range from 50% to 60%; even so, storm-related transport typically exceeds 80%. Hence, in urban environments, non-point-source appear to be the dominant contributors to the fluxes of these constituents.

Mars Characterization for Future Missions

NASA Technical Reports Server (NTRS)

Bridger, Alison F. C.; Haberle, Robert M.

1999-01-01

Annual simulations of Mars' atmosphere made with the NASA Ames Mars General Circulation Model have been used to extract and generate products to provide statistical products that detail the variability of Mars' atmosphere on fairly short time scales. These products are needed for the creation of a new version of Mars-GRAM, due for completion in June, 1999. The updated Mars-Gram, in turn, will provide guidance for forthcoming aerobraking and aerocapture activities. We have created files containing zonally-averaged fields (temperatures, densities, pressures, and winds, all on z-surfaces), as well as zonally-averaged diurnal and semidiurnal tidal amplitudes and phases. All fields represent a time averaged state (over either 5 or 30 sols), and all fields are available at each of 12 seasons for a Mars year (the seasons being 30deg of Ls apart). Files for low and moderate dust loading cases are liable via anonymous ftp. Files for a high dust case will be in place shortly.

The importance of temporal inequality in quantifying vegetated filter strip removal efficiencies

NASA Astrophysics Data System (ADS)

Gall, H. E.; Schultz, D.; Mejia, A.; Harman, C. J.; Raj, C.; Goslee, S.; Veith, T.; Patterson, P. H.

2017-12-01

Vegetated filter strips (VFSs) are best management practices (BMPs) commonly implemented adjacent to row-cropped fields to trap overland transport of sediment and other constituents often present in agricultural runoff. VFSs are generally reported to have high sediment removal efficiencies (i.e., 70 - 95%); however, these values are typically calculated as an average of removal efficiencies observed or simulated for individual events. We argue that due to: (i) positively correlated sediment concentration-discharge relationships; (ii) strong temporal inequality exhibited by sediment transport; and (iii) decreasing VFS performance with increasing flow rates, VFS removal efficiencies over annual time scales may be significantly lower than the per-event values or averages typically reported in the literature and used in decision-making models. By applying a stochastic approach to a two-component VFS model, we investigated the extent of the disparity between two calculation methods: averaging efficiencies from each event over the course of one year, versus reporting the total annual load reduction. We examined the effects of soil texture, concentration-discharge relationship, and VFS slope to reveal the potential errors that may be incurred by ignoring the effects of temporal inequality in quantifying VFS performance. Simulation results suggest that errors can be as low as < 2% and as high as > 20%, with the differences between the two methods of removal efficiency calculations greatest for: (i) soils with high percentage of fine particulates; (ii) VFSs with higher slopes; and (iii) strongly positive concentration-discharge relationships. These results can aid in annual-scale decision making for achieving downstream water quality goals.

Temporal trends in the acidity of precipitation and surface waters of New York

USGS Publications Warehouse

Peters, Norman E.; Schroeder, Roy A.; Troutman, David E.

1982-01-01

Statistical analyses of precipitation data from a nine-station monitoring network indicate little change in pH from 1965-78 within New York State as a whole but suggest that pH of bulk precipitation has decreased in the western part of the State by approximately 0.2 pH units since 1965 and increased in the eastern part by a similar amount. This trend is equivalent to an annual change in hydrogen-ion concentration of 0.2 microequivalents per liter. An average annual increase in precipitation quantity of 2 to 3 percent since 1965 has resulted in an increased acid load in the western and central parts of the State. During 1965-78, sulfate concentration in precipitation decreased an average of 1-4 percent annually. In general, no trend in nitrate was detected. Calculated trends in hydrogen-ion concentration do not correlate with measured trends of sulfate and nitrate, which suggests variable neutralization of hydrogen ion, possibly by particles from dry deposition. Neutralization has produced an increase of about 0.3 pH units in nonurban areas and 0.7 pH units in urban areas. Statistical analyses of chemical data from several streams throughout New York suggest that sulfate concentrations decreased an average of 1 to 4 percent per year. This decrease is comparable to the sulfate decrease in precipitation during the same period. In most areas of the State, chemical contributions from urbanization and farming, as well as the neutralizing effect of carbonate soils, conceal whatever effects acid precipitation may have on pH of streams.

Using remotely sensed imagery to estimate potential annual pollutant loads in river basins.

PubMed

He, Bin; Oki, Kazuo; Wang, Yi; Oki, Taikan

2009-01-01

Land cover changes around river basins have caused serious environmental degradation in global surface water areas, in which the direct monitoring and numerical modeling is inherently difficult. Prediction of pollutant loads is therefore crucial to river environmental management under the impact of climate change and intensified human activities. This research analyzed the relationship between land cover types estimated from NOAA Advanced Very High Resolution Radiometer (AVHRR) imagery and the potential annual pollutant loads of river basins in Japan. Then an empirical approach, which estimates annual pollutant loads directly from satellite imagery and hydrological data, was investigated. Six water quality indicators were examined, including total nitrogen (TN), total phosphorus (TP), suspended sediment (SS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and Dissolved Oxygen (DO). The pollutant loads of TN, TP, SS, BOD, COD, and DO were then estimated for 30 river basins in Japan. Results show that the proposed simulation technique can be used to predict the pollutant loads of river basins in Japan. These results may be useful in establishing total maximum annual pollutant loads and developing best management strategies for surface water pollution at river basin scale.

46 CFR 42.11-20 - Application for annual survey.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 2 2014-10-01 2014-10-01 false Application for annual survey. 42.11-20 Section 42.11-20... BY SEA Applications for Load Line Assignments, Surveys, and Certificates § 42.11-20 Application for annual survey. (a) The owner, master, or agent of a vessel holding a load line certificate shall apply to...

46 CFR 42.11-20 - Application for annual survey.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 2 2012-10-01 2012-10-01 false Application for annual survey. 42.11-20 Section 42.11-20... BY SEA Applications for Load Line Assignments, Surveys, and Certificates § 42.11-20 Application for annual survey. (a) The owner, master, or agent of a vessel holding a load line certificate shall apply to...

46 CFR 42.11-20 - Application for annual survey.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 2 2013-10-01 2013-10-01 false Application for annual survey. 42.11-20 Section 42.11-20... BY SEA Applications for Load Line Assignments, Surveys, and Certificates § 42.11-20 Application for annual survey. (a) The owner, master, or agent of a vessel holding a load line certificate shall apply to...

46 CFR 42.11-20 - Application for annual survey.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 2 2011-10-01 2011-10-01 false Application for annual survey. 42.11-20 Section 42.11-20... BY SEA Applications for Load Line Assignments, Surveys, and Certificates § 42.11-20 Application for annual survey. (a) The owner, master, or agent of a vessel holding a load line certificate shall apply to...

46 CFR 42.11-20 - Application for annual survey.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Application for annual survey. 42.11-20 Section 42.11-20... BY SEA Applications for Load Line Assignments, Surveys, and Certificates § 42.11-20 Application for annual survey. (a) The owner, master, or agent of a vessel holding a load line certificate shall apply to...

Geochemistry and geohydrology of the West Decker and Big Sky coal-mining areas, southeastern Montana

USGS Publications Warehouse

Davis, R.E.

1984-01-01

In the West Decker Mine area, water levels west of the mine at post-mining equilibrium may be almost 12 feet higher than pre-mining levels. Dissolved-solids concentration in water from coal aquifers is about 1,400 milligrams per liter and from mine spoils is about 2,500 milligrams per liter. About 13 years will be required for ground water moving at an average velocity of 2 feet per day to flow from the spoils to the Tongue River Reservoir. The increase in dissolved-solids load to the reservoir due to mining will be less than 1 percent. In the Big Sky Mine area, water levels at post-mining equilibrium will closely resemble pre-mining levels. Dissolved-solids concentration in water from coal aquifers is about 2,700 milligrams per liter and from spoils is about 3,700 milligrams per liter. About 36 to 60 years will be required for ground water moving at an average velocity of 1.2 feet per day to flow from the spoils to Rosebud Creek. The average annual increase in dissolved-solids load to the creek due to mining will be about 2 percent, although a greater increase probably will occur during summer months when flow in the creek is low. (USGS)

Modal analysis of annual runoff volume and sediment load in the Yangtze river-lake system for the period 1956-2013.

PubMed

Chen, Huai; Zhu, Lijun; Wang, Jianzhong; Fan, Hongxia; Wang, Zhihuan

2017-07-01

This study focuses on detecting trends in annual runoff volume and sediment load in the Yangtze river-lake system. Times series of annual runoff volume and sediment load at 19 hydrological gauging stations for the period 1956-2013 were collected. Based on the Mann-Kendall test at the 1% significance level, annual sediment loads in the Yangtze River, the Dongting Lake and the Poyang Lake were detected with significantly descending trends. The power spectrum estimation indicated predominant oscillations with periods of 8 and 20 years are embedded in the runoff volume series, probably related to the El Niño Southern Oscillation (2-7 years) and Pacific Decadal Oscillation (20-30 years). Based on dominant components (capturing more than roughly 90% total energy) extracted by the proper orthogonal decomposition method, total change ratios of runoff volume and sediment load during the last 58 years were evaluated. For sediment load, the mean CRT value in the Yangtze River is about -65%, and those in the Dongting Lake and the Poyang Lake are -92.2% and -87.9% respectively. Particularly, the CRT value of the sediment load in the channel inflow of the Dongting Lake is even -99.7%. The Three Gorges Dam has intercepted a large amount of sediment load and decreased the sediment load downstream.

An initial SPARROW model of land use and in-stream controls on total organic carbon in streams of the conterminous United States

USGS Publications Warehouse

Shih, Jhih-Shyang; Alexander, Richard B.; Smith, Richard A.; Boyer, Elizabeth W.; Shwarz, Grogory E.; Chung, Susie

2010-01-01

Watersheds play many important roles in the carbon cycle: (1) they are a site for both terrestrial and aquatic carbon dioxide (CO2) removal through photosynthesis; (2) they transport living and decomposing organic carbon in streams and groundwater; and (3) they store organic carbon for widely varying lengths of time as a function of many biogeochemical factors. Using the U.S. Geological Survey (USGS) Spatially Referenced Regression on Watershed Attributes (SPARROW) model, along with long-term monitoring data on total organic carbon (TOC), this research quantitatively estimates the sources, transport, and fate of the long-term mean annual load of TOC in streams of the conterminous United States. The model simulations use surrogate measures of the major terrestrial and aquatic sources of organic carbon to estimate the long-term mean annual load of TOC in streams. The estimated carbon sources in the model are associated with four land uses (urban, cultivated, forest, and wetlands) and autochthonous fixation of carbon (stream photosynthesis). Stream photosynthesis is determined by reach-level application of an empirical model of stream chlorophyll based on total phosphorus concentration, and a mechanistic model of photosynthetic rate based on chlorophyll, average daily solar irradiance, water column light attenuation, and reach dimensions. It was found that the estimate of in-stream photosynthesis is a major contributor to the mean annual TOC load per unit of drainage area (that is, yield) in large streams, with a median share of about 60 percent of the total mean annual carbon load in streams with mean flows above 500 cubic feet per second. The interquartile range of the model predictions of TOC from in-stream photosynthesis is from 0.1 to 0.4 grams (g) carbon (C) per square meter (m-2) per day (day-1) for the approximately 62,000 stream reaches in the continental United States, which compares favorably with the reported literature range for net carbon fixation by phytoplankton in lakes and streams. The largest contributors per unit of drainage area to the mean annual stream TOC load among the terrestrial sources are, in descending order: wetlands, urban lands, mixed forests, agricultural lands, evergreen forests, and deciduous forests . It was found that the SPARROW model estimates of TOC contributions to streams associated with these land uses are also consistent with literature estimates. SPARROW model calibration results are used to simulate the delivery of TOC loads to the coastal areas of seven major regional drainages. It was found that stream photosynthesis is the largest source of the TOC yields ( about 50 percent) delivered to the coastal waters in two of the seven regional drainages (the Pacific Northwest and Mississippi-Atchafalaya-Red River basins ), whereas terrestrial sources are dominant (greater than 60 percent) in all other regions (North Atlantic, South Atlantic-Gulf, California, Texas-Gulf, and Great Lakes).

Pollutant loading from low-density residential neighborhoods in California.

PubMed

Bale, Andrew E; Greco, Steven E; Pitton, Bruno J L; Haver, Darren L; Oki, Lorence R

2017-08-01

This paper presents a comparison of pollutant load estimations for runoff from two geographically distinct residential suburban neighborhoods in northern and southern California. The two neighborhoods represent a single urban land use type: low-density residential in small catchments (<0.3 km 2 ) under differing regional climates and irrigation practices. Pollutant loads of pesticides, nutrients, and drinking water constituents of concern are estimated for both storm and non-storm runoff. From continuous flow monitoring, it was found that a daily cycle of persistent runoff that peaks mid-morning occurs at both sites. These load estimations indicate that many residential neighborhoods in California produce significant non-storm pollutant loads year-round. Results suggest that non-storm flow accounted for 47-69% of total annual runoff and significantly contributed to annual loading rates of most nutrients and pesticides at both sites. At the Southern California site, annual non-storm loads are 1.2-10 times higher than storm loads of all conventional constituents and nutrients with one exception (total suspended solids). At the Northern California site, annual storm loads range from 51 to 76% of total loads for all conventional constituents and nutrients with one exception (total dissolved solids). Non-storm yields of pesticides at the Southern California site range from 1.3-65 times higher than those at the Northern California site. The disparity in estimated pollutant loads between the two sites indicates large potential variation from site-to-site within the state and suggests neighborhoods in drier and milder climates may produce significantly larger non-storm loads due to persistent dry season runoff and year-round pest control.

Analysis of a solar PV/battery/DG set-based hybrid system for a typical telecom load: a case study

NASA Astrophysics Data System (ADS)

Iqbal, A.; Arif, M. Saad Bin; Ayob, Shahrin Md; Siddiqui, Khursheed

2017-03-01

This paper analyses the technical and economic feasibility of using a hybrid renewable energy source for a typical telecom load in the state of Qatar. The hybrid system considered in this work consists of a solar photovoltaic with storage battery and diesel generator set. For this particular hybrid system, the meteorological data of solar irradiance in Doha city (latitude 25.15 ° North and longitude 51.33 ° East) are taken from NASA surface meteorology and solar energy websites. The solar irradiance in Doha is 5.33 kWh/m2/day on an annual average scale. The data are also taken through the study of load consumption of Qatar telecommunication hybrid power system. The system is designed and its techno-economic analysis is carried out using the Hybrid Optimization Model for Electrical Renewable software. The results show both technical and economic viability of replacing the conventional DG sets with the proposed renewable energy source.

Impact assessment of projected climate change on diffuse phosphorous loss in Xin'anjiang catchment, China.

PubMed

Zhai, Xiaoyan; Zhang, Yongyong

2018-02-01

Diffuse nutrient loss is a serious threat to water security and has severely deteriorated water quality throughout the world. Xin'anjiang catchment, as a main drinking water source for Hangzhou City, has been a national concern for water environment protection with payment for watershed services construction. Detection of diffuse phosphorous (DP) pollution dynamics under climate change is significant for sustainable water quality management. In this study, the impact of projected climate change on DP load was analyzed using SWAT to simulate the future changes of diffuse components (carriers: water discharge and sediment; nutrient: DP) at both station and sub-catchment scales under three climate change scenarios (RCP2.6, RCP4.5, and RCP8.5). Results showed that wetting and warming years were expected with increasing tendencies of both precipitation and temperature in the two future periods (2020s: 2021~2030, 2030s: 2031~2040) except in the 2020s in the RCP2.6 scenario, and the annual average increasing ratios of precipitation and temperature reached - 1.79~3.79% and 0.48~1.27 °C, respectively, comparing with those in the baseline (2000s: 2001~2010). Climate change evidently altered annual and monthly average water discharge and sediment load, while it has a remarkable impact on the timing and monthly value of DP load at station scale. DP load tended to increase in the non-flood season at Yuliang due to strengthened nutrient flushing from rice land into rivers with increasing precipitation and enhanced phosphorous cycle in soil layers with increasing temperature, while it tended to decrease in the flood season at Yuliang and in most months at Tunxi due to restricted phosphorous reaction with reduced dissolved oxygen content and enhanced dilution effect. Spatial variability existed in the changes of sediment load and DP load at sub-catchment scale due to climate change. DP load tended to decrease in most sub-catchments and was the most remarkable in the RCP8.5 scenario (2020s, - 9.00~2.63%; 2030s, - 11.16~7.89%), followed by RCP2.6 (2020s, - 10.00~2.90%; 2030s, - 9.00~6.63%) and RCP4.5 (2020s, - 6.81~5.49%, 2030s, - 10.00~9.09%) scenarios. Decreasing of DP load mainly aggregated in the western and eastern mountainous regions, while it tended to increase in the northern and middle regions. This study was expected to provide insights into diffuse nutrient loss control and management in Xin'anjiang catchment, and scientific references for the implementation of water environmental protection in China.

Analysis of the relationship between economic growth and industrial pollution in Zaozhuang, China-based on the hypothesis of the environmental Kuznets curve.

PubMed

Liu, Xiao-Hui; Wang, Wei-Liang; Lu, Shao-Yong; Wang, Yu-Fan; Ren, Zongming

2016-08-01

In Zaozhuang, economic development affects the discharge amount of industrial wastewater, chemical oxygen demand (COD), and ammonia nitrogen (NH3-N). To reveal the trend of water environmental quality related to the economy in Zaozhuang, this paper simulated the relationships between industrial wastewater discharge, COD, NH3-N load, and gross domestic product (GDP) per capita for Zaozhuang (2002-2012) using environmental Kuznets curve (EKC) models. The results showed that the added value of industrial GDP, the per capita GDP, and wastewater emission had average annual growth rates of 16.62, 16.19, and 17.89 %, respectively, from 2002 to 2012, while COD and NH3-N emission in 2012, compared with 2002, showed average annual decreases of 10.70 and 31.12 %, respectively. The export of EKC models revealed that industrial wastewater discharge had a typical inverted-U-shaped relationship with per capita GDP. However, both COD and NH3-N showed the binding curve of the left side of the "U" curve and left side U-shaped curve. The economy in Zaozhuang had been at the "fast-growing" stage, with low environmental pollution according to the industrial pollution level. In recent years, Zaozhuang has abated these heavy-pollution industries emphatically, so pollutants have been greatly reduced. Thus, Zaozhuang industrial wastewater treatment has been quite effective, with water quality improved significantly. The EKC models provided scientific evidence for estimating industrial wastewater discharge, COD, and NH3-N load as well as their changeable trends for Zaozhuang from an economic perspective.

Progress report on the effects of highway construction on suspended-sediment discharge in the Coal River and Trace Fork, West Virginia, 1975-81

USGS Publications Warehouse

Downs, S.C.; Appel, David H.

1986-01-01

Construction of the four-lane Appalachian Corridon G highway disturbed about 2 sq mi in the Coal River and 0.35 sq mi of the 4.75 sq mi Trace Fork basin in southern West Virginia. Construction had a negligible effect on runoff and suspended-sediment load in the Coal River and its major tributaries, the Little Coal and Big Coal Rivers. Drainage areas of the mainstem sites in the Coal River basin ranged from 269 to 862 sq mi, and average annual suspended-sediment yields ranged from 535 to 614 tons/sq mi for the 1975-81 water years. Suspended-sediment load in the smaller Trace Fork basin (4.72 sq mi) was significantly affected by the highway construction. Based on data from undisturbed areas upstream from construction, the normal background load at Trace Fork downstream from construction during the period July 1980 to September 1981 was estimated to be 830 tons; the measured load was 2,385 tons. Runoff from the 0.35 sq mi area disturbed by highway construction transported approximately 1,550 tons of sediment. Suspended-sediment loads from the construction zone were also higher than normal background loads during storms. (USGS)

Estimating annual suspended-sediment loads in the northern and central Appalachian Coal region

USGS Publications Warehouse

Koltun, G.F.

1985-01-01

Multiple-regression equations were developed for estimating the annual suspended-sediment load, for a given year, from small to medium-sized basins in the northern and central parts of the Appalachian coal region. The regression analysis was performed with data for land use, basin characteristics, streamflow, rainfall, and suspended-sediment load for 15 sites in the region. Two variables, the maximum mean-daily discharge occurring within the year and the annual peak discharge, explained much of the variation in the annual suspended-sediment load. Separate equations were developed employing each of these discharge variables. Standard errors for both equations are relatively large, which suggests that future predictions will probably have a low level of precision. This level of precision, however, may be acceptable for certain purposes. It is therefore left to the user to asses whether the level of precision provided by these equations is acceptable for the intended application.

Using regression methods to estimate stream phosphorus loads at the Illinois River, Arkansas

USGS Publications Warehouse

Haggard, B.E.; Soerens, T.S.; Green, W.R.; Richards, R.P.

2003-01-01

The development of total maximum daily loads (TMDLs) requires evaluating existing constituent loads in streams. Accurate estimates of constituent loads are needed to calibrate watershed and reservoir models for TMDL development. The best approach to estimate constituent loads is high frequency sampling, particularly during storm events, and mass integration of constituents passing a point in a stream. Most often, resources are limited and discrete water quality samples are collected on fixed intervals and sometimes supplemented with directed sampling during storm events. When resources are limited, mass integration is not an accurate means to determine constituent loads and other load estimation techniques such as regression models are used. The objective of this work was to determine a minimum number of water-quality samples needed to provide constituent concentration data adequate to estimate constituent loads at a large stream. Twenty sets of water quality samples with and without supplemental storm samples were randomly selected at various fixed intervals from a database at the Illinois River, northwest Arkansas. The random sets were used to estimate total phosphorus (TP) loads using regression models. The regression-based annual TP loads were compared to the integrated annual TP load estimated using all the data. At a minimum, monthly sampling plus supplemental storm samples (six samples per year) was needed to produce a root mean square error of less than 15%. Water quality samples should be collected at least semi-monthly (every 15 days) in studies less than two years if seasonal time factors are to be used in the regression models. Annual TP loads estimated from independently collected discrete water quality samples further demonstrated the utility of using regression models to estimate annual TP loads in this stream system.

On the Trend of the Annual Mean, Maximum, and Minimum Temperature and the Diurnal Temperature Range in the Armagh Observatory, Northern Ireland, Dataset, 1844 -2012

NASA Technical Reports Server (NTRS)

Wilson, Robert M.

2013-01-01

Examined are the annual averages, 10-year moving averages, decadal averages, and sunspot cycle (SC) length averages of the mean, maximum, and minimum surface air temperatures and the diurnal temperature range (DTR) for the Armagh Observatory, Northern Ireland, during the interval 1844-2012. Strong upward trends are apparent in the Armagh surface-air temperatures (ASAT), while a strong downward trend is apparent in the DTR, especially when the ASAT data are averaged by decade or over individual SC lengths. The long-term decrease in the decadaland SC-averaged annual DTR occurs because the annual minimum temperatures have risen more quickly than the annual maximum temperatures. Estimates are given for the Armagh annual mean, maximum, and minimum temperatures and the DTR for the current decade (2010-2019) and SC24.

Concentrations, loads, and yields of total phosphorus, total nitrogen, and suspended sediment and bacteria concentrations in the Wister Lake Basin, Oklahoma and Arkansas, 2011-13

USGS Publications Warehouse

Buck, Stephanie D.

2014-01-01

The Poteau Valley Improvement Authority uses Wister Lake in southeastern Oklahoma as a public water supply. Total phosphorus, total nitrogen, and suspended sediments from agricultural runoff and discharges from wastewater treatment plants and other sources have degraded water quality in the lake. As lake-water quality has degraded, water-treatment cost, chemical usage, and sludge production have increased for the Poteau Valley Improvement Authority. The U.S. Geological Survey (USGS), in cooperation with the Poteau Valley Improvement Authority, investigated and summarized concentrations of total phosphorus, total nitrogen, suspended sediment, and bacteria (Escherichia coli and Enterococcus sp.) in surface water flowing to Wister Lake. Estimates of total phosphorus, total nitrogen, and suspended sediment loads, yields, and flow-weighted mean concentrations of total phosphorus and total nitrogen concentrations were made for the Wister Lake Basin for a 3-year period from October 2010 through September 2013. Data from water samples collected at fixed time increments during base-flow conditions and during runoff conditions at the Poteau River at Loving, Okla. (USGS station 07247015), the Poteau River near Heavener, Okla. (USGS station 07247350), and the Fourche Maline near Leflore, Okla. (USGS station 07247650), water-quality stations were used to evaluate water quality over the range of streamflows in the basin. These data also were collected to estimate annual constituent loads and yields by using regression models. At the Poteau River stations, total phosphorus, total nitrogen, and suspended sediment concentrations in surface-water samples were significantly larger in samples collected during runoff conditions than in samples collected during base-flow conditions. At the Fourche Maline station, in contrast, concentrations of these constituents in water samples collected during runoff conditions were not significantly larger than concentrations during base-flow conditions. Flow-weighted mean total phosphorus concentrations at all three stations from 2011 to 2013 were several times larger than the Oklahoma State Standard for Scenic Rivers (0.037 milligrams per liter [mg/L]), with the largest flow-weighted phosphorus concentrations typically being measured at the Poteau River at Loving, Okla., station. Flow-weighted mean total nitrogen concentrations did not vary substantially between the Poteau River stations and the Fourche Maline near Leflore, Okla., station. At all of the sampled water-quality stations, bacteria (Escherichia coli and Enterococcus sp.) concentrations were substantially larger in water samples collected during runoff conditions than in water samples collected during base-flow conditions from 2011 to 2013. Estimated annual loads of total phosphorus, total nitrogen, and suspended sediment in the Poteau River stations during runoff conditions ranged from 82 to 98 percent of the total annual loads of those constituents. Estimated annual loads of total phosphorus, total nitrogen, and suspended sediment in the Fourche Maline during runoff conditions ranged from 86 to nearly 100 percent of the total annual loads. Estimated seasonal total phosphorus loads generally were smallest during base-flow and runoff conditions in autumn. Estimated seasonal total phosphorus loads during base-flow conditions tended to be largest in winter and during runoff conditions tended to be largest in the spring. Estimated seasonal total nitrogen loads tended to be smallest in autumn during base-flow and runoff conditions and largest in winter during runoff conditions. Estimated seasonal suspended sediment loads tended to be smallest during base-flow conditions in the summer and smallest during runoff conditions in the autumn. The largest estimated seasonal suspended sediment loads during runoff conditions typically were in the spring. The estimated mean annual total phosphorus yield was largest at the Poteau River at Loving, Okla., water-quality station. The estimated mean annual total phosphorus yield was largest during base flow at the Poteau River at Loving, Okla., water-quality station and at both of the Poteau River water-quality stations during runoff conditions. The estimated mean annual total nitrogen yields were largest at the Poteau River water-quality stations. Estimated mean annual total nitrogen yields were largest during base-flow and runoff conditions at the Poteau River at Loving, Okla., water-quality station. The estimated mean annual suspended sediment yield was largest at the Poteau River near Heavener, Okla., water-quality station during base-flow and runoff conditions. Flow-weighted mean concentrations indicated that total phosphorus inputs from the Poteau River Basin in the Wister Lake Basin were larger than from the Fourche Maline Basin. Flow-weighted mean concentrations of total nitrogen did not vary spatially in a consistent manner. The Poteau River and the Fourche Maline contributed estimated annual total phosphorus loads of 137 to 278 tons per year (tons/yr) to Wister Lake. Between 89 and 95 percent of the annual total phosphorus loads were transported to Wister Lake during runoff conditions. The Poteau River and the Fourche Maline contributed estimated annual total nitrogen loads of 657 to 1,294 tons/yr, with 86 to 94 percent of the annual total nitrogen loads being transported to Wister Lake during runoff conditions. The Poteau River and the Fourche Maline contributed estimated annual total suspended sediment loads of 110,919 to 234,637 tons/yr, with 94 to 99 percent of the annual suspended sediment loads being transported to Wister Lake during runoff conditions. Most of the total phosphorus and suspended sediment were delivered to Wister Lake during runoff conditions in the spring. The majority of the total nitrogen was delivered to Wister Lake during runoff conditions in winter.

Measurements of coarse particulate organic matter transport in steep mountain streams and estimates of decadal CPOM exports

NASA Astrophysics Data System (ADS)

Bunte, Kristin; Swingle, Kurt W.; Turowski, Jens M.; Abt, Steven R.; Cenderelli, Daniel A.

2016-08-01

Coarse particulate organic matter (CPOM) provides a food source for benthic organisms, and the fluvial transport of CPOM is one of the forms in which carbon is exported from a forested basin. However, little is known about transport dynamics of CPOM, its relation to discharge, and its annual exports from mountain streams. Much of this knowledge gap is due to sampling difficulties. In this study, CPOM was sampled over one-month snowmelt high flow seasons in two high-elevation, subalpine, streams in the Rocky Mountains. Bedload traps developed for sampling gravel bedload were found to be suitable samplers for CPOM transport. CPOM transport rates were well related to flow in consecutive samples but showed pronounced hysteresis over the diurnal fluctuations of flow, between consecutive days, and over the rising and falling limbs of the high-flow season. In order to compute annual CPOM load, hysteresis effects require intensive sampling and establishing separate rating curves for all rising and falling limbs. Hysteresis patterns of CPOM transport relations identified in the well-sampled study streams may aid with estimates of CPOM transport and export in less well-sampled Rocky Mountain streams. Transport relations for CPOM were similar among three high elevation mountain stream with mainly coniferous watersheds. Differences among streams can be qualitatively attributed to differences in CPOM contributions from litter fall, from the presence of large woody debris, its grinding into CPOM sized particles by gravel-cobble bedload transport, hillslope connectivity, drainage density, and biological consumption. CPOM loads were 3.6 and 3.2 t/yr for the two Rocky Mountain streams. Adjusted to reflect decadal averages, values increased to 11.3 and 10.2 t/yr. CPOM yields related to the entire watershed were 2.7 and 4 kg/ha/yr for the years studied, but both streams exported similar amounts of 6.5 and 6.6 kg/ha/yr when taking the forested portion of the watershed into account. To reflect decadal averages, CPOM yields per basin area were adjusted to 8.6 and 12.6 kg/ha/yr and to 21 kg/ha/yr for the forested watershed parts. CPOM yield may be more meaningfully characterized if annual CPOM loads are normalized by the area of a seam along the stream banks together with the stream surface area rather than by the forested or total watershed area.

The effect of changes in sea surface temperature on linear growth of Porites coral in Ambon Bay

DOE Office of Scientific and Technical Information (OSTI.GOV)

Corvianawatie, Corry, E-mail: corvianawatie@students.itb.ac.id; Putri, Mutiara R., E-mail: mutiara.putri@fitb.itb.ac.id; Cahyarini, Sri Y., E-mail: yuda@geotek.lipi.go.id

Coral is one of the most important organisms in the coral reef ecosystem. There are several factors affecting coral growth, one of them is changes in sea surface temperature (SST). The purpose of this research is to understand the influence of SST variability on the annual linear growth of Porites coral taken from Ambon Bay. The annual coral linear growth was calculated and compared to the annual SST from the Extended Reconstructed Sea Surface Temperature version 3b (ERSST v3b) model. Coral growth was calculated by using Coral X-radiograph Density System (CoralXDS) software. Coral sample X-radiographs were used as input data.more » Chronology was developed by calculating the coral’s annual growth bands. A pair of high and low density banding patterns observed in the coral’s X-radiograph represent one year of coral growth. The results of this study shows that Porites coral extents from 2001-2009 and had an average growth rate of 1.46 cm/year. Statistical analysis shows that the annual coral linear growth declined by 0.015 cm/year while the annual SST declined by 0.013°C/year. SST and the annual linear growth of Porites coral in the Ambon Bay is insignificantly correlated with r=0.304 (n=9, p>0.05). This indicates that annual SST variability does not significantly influence the linear growth of Porites coral from Ambon Bay. It is suggested that sedimentation load, salinity, pH or other environmental factors may affect annual linear coral growth.« less

50 CFR 217.172 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

... dolphin (Grampus griseus)—100 (an average of 20 annually). (vi) Killer whale (Orcinus orca)—100 (an... right whale (Eubalaena glacialis)—120 (an average of 24 annually). (ii) Fin whale (Balaenoptera physalus)—145 (an average of 29 annually). (iii) Humpback whale (Megaptera novaeangliae)—390 (an average of 78...

50 CFR 217.172 - Permissible methods of taking.

Code of Federal Regulations, 2014 CFR

2014-10-01

... dolphin (Grampus griseus)—100 (an average of 20 annually). (vi) Killer whale (Orcinus orca)—100 (an... right whale (Eubalaena glacialis)—120 (an average of 24 annually). (ii) Fin whale (Balaenoptera physalus)—145 (an average of 29 annually). (iii) Humpback whale (Megaptera novaeangliae)—390 (an average of 78...

Concentrations and loads of suspended sediment and trace element pollutants in a small semi-arid urban tributary, San Francisco Bay, California.

PubMed

McKee, Lester J; Gilbreath, Alicia N

2015-08-01

Water-quality policy documents throughout the world often identify urban stormwater as a large and controllable impact to sensitive ecosystems, yet there is often limited data to characterize concentrations and loads especially for rare and more difficult to quantify pollutants. In response, concentrations of suspended sediments and silver, mercury and selenium including speciation, and other trace elements were measured in dry and wet weather stormwater flow from a 100% urban watershed near San Francisco. Suspended sediment concentrations ranged between 1.4 and 2700 mg/L and varied with storm intensity. Turbidity was shown to correlate strongly with suspended sediments and most trace elements and was used as a surrogate with regression to estimate concentrations during unsampled periods and to compute loads. Mean suspended sediment yield was 31.5 t/km(2)/year. Total mercury ranged between 1.4 and 150 ng/L and was, on average, 92% particulate, 0.9% methylated, and 1.2% acid labile. Total mercury yield averaged 5.7 μg/m(2)/year. Total selenium ranged between non-detect and 2.9 μg/L and, on average, the total load (0.027 μg/m(2)/year) was 61% transported in dissolved phase. Selenate (Se(VI)) was the dominant species. Silver concentrations ranged between non-detect and 0.11 μg/L. Concentrations and loads of other trace elements were also highly variable and were generally similar to other urban systems with the exceptions of Ag and As (seldom reported) and Cr and Zn which exhibited concentrations and loads in the upper range of those reported elsewhere. Consistent with the semi-arid climatic setting, >95% of suspended sediment, 94% of total Hg, and 85-95 % of all other trace element loads were transported during storm flows with the exception of selenium which showed an inverse relationship between concentration and flow. Treatment of loads is made more challenging in arid climate settings due to low proportions of annual loads and greater dissolved phase during low flow conditions. This dataset fills an important local data gap for highly urban watersheds of San Francisco Bay. The field and interpretative methods, the uniqueness of the analyte list, and resulting information have general applicability for managing pollutant concentrations and loads in urban watersheds in other parts of the world and may have particularly useful application in more arid climates.

Stage-discharge relations and annual nitrogen and phosphorus load estimates for stream sites in the Elk River Basin, 2006–2008

USGS Publications Warehouse

Hoos, Anne B.; Williams, Shannon D.; Wolfe, William J.

2016-11-22

The U.S. Geological Survey, in cooperation with the Tennessee Department of Environment and Conservation (TDEC), measured continuous discharge at 4 water-quality monitoring sites and developed stage-discharge ratings for 10 additional water-quality monitoring sites in the Elk River Basin during 2006 through 2008. The discharge data were collected to support stream load assessments by TDEC. Annual nitrogen and phosphorus loads were estimated for the four sites where continuous daily discharge records were collected. Reported loads for the period 2006 through 2008 are not representative of long-term mean annual conditions at the sites in this study, however, because of severe drought conditions in the Elk River Basin during this period.

Constituent loads and flow-weighted average concentrations for major subbasins of the upper Red River of the North Basin, 1997-99

USGS Publications Warehouse

Sether, Bradley A.; Berkas, Wayne R.; Vecchia, Aldo V.

2004-01-01

Data were collected at 11 water-quality sampling sites in the upper Red River of the North (Red River) Basin from May 1997 through September 1999 to describe the water-quality characteristics of the upper Red River and to estimate constituent loads and flow-weighted average concentrations for major tributaries of the Red River upstream from the bridge crossing the Red River at Perley, Minn. Samples collected from the sites were analyzed for 5-day biochemical oxygen demand, bacteria, dissolved solids, nutrients, and suspended sediment.Concentration data indicated the median concentrations for most constituents and sampling sites during the study period were less than existing North Dakota and Minnesota standards or guidelines. However, more than 25 percent of the samples for the Red River at Perley, Minn., site had fecal coliform concentrations that were greater than 200 colonies per 100 milliliters, indicating an abundance of pathogens in the upper Red River Basin. Although total nitrite plus nitrate concentrations generally increased in a downstream direction, the median concentrations for all sites were less than the North Dakota suggested guideline of 1.0 milligram per liter. Total and dissolved phosphorus concentrations also generally increased in a downstream direction, but, for those constituents, the median concentrations for most sampling sites exceeded the North Dakota suggested guideline of 0.1 milligram per liter.For dissolved solids, nutrients, and suspended sediments, a relation between constituent concentration and streamflow was determined using the data collected during the study period. The relation was determined by a multiple regression model in which concentration was the dependent variable and streamflow was the primary explanatory variable. The regression model was used to compute unbiased estimates of annual loads for each constituent and for each of eight primary water-quality sampling sites and to compute the degree of uncertainty associated with each estimated annual load. The estimated annual loads for the eight primary sites then were used to estimate annual loads for five intervening reaches in the study area.  Results were used as a screening tool to identify which subbasins contributed a disproportionate amount of pollutants to the Red River. To compare the relative water quality of the different subbasins, an estimated flow-weighted average (FWA) concentration was computed from the estimated average annual load and the average annual streamflow for each subbasin.The 5-day biochemical oxygen demands in the upper Red River Basin were fairly small, and medians ranged from 1 to 3 milligrams per liter. The largest estimated FWA concentration for dissolved solids (about 630 milligrams per liter) was for the Bois de Sioux River near Doran, Minn., site. The Otter Tail River above Breckenridge, Minn., site had the smallest estimated FWA concentration (about 240 milligrams per liter). The estimated FWA concentrations for dissolved solids for the main-stem sites ranged from about 300 to 500 milligrams per liter and generally increased in a downstream direction.The estimated FWA concentrations for total nitrite plus nitrate for the main-stem sites increased from about 0.2 milligram per liter for the Red River below Wahpeton, N. Dak., site to about 0.9 milligram per liter for the Red River at Perley, Minn., site. Much of the increase probably resulted from flows from the tributary sites and intervening reaches, excluding the Otter Tail River above Breckenridge, Minn., site. However, uncertainty in the estimated concentrations prevented any reliable conclusions regarding which sites or reaches contributed most to the increase.The estimated FWA concentrations for total ammonia for the main-stem sites increased from about 0.05 milligram per liter for the Red River above Fargo, N. Dak., site to about 0.15 milligram per liter for the Red River near Harwood, N. Dak., site. The increase resulted from a decrease in flows in the Red River above Fargo, N. Dak., to the Red River near Harwood, N. Dak., intervening reach and the large load for that reach.The estimated FWA concentrations for total organic nitrogen for the main-stem sites were relatively constant and ranged from about 0.5 to 0.7 milligram per liter. The relatively constant concentrations were in sharp contrast to the total nitrite plus nitrate concentrations, which increased about fivefold between the Red River below Wahpeton, N. Dak., site and the Red River at Perley, Minn., site.The Red River near Harwood, N. Dak., to the Red River at Perley, Minn., intervening reach had the largest estimated FWA concentration for total nitrogen (about 2.9 milligrams per liter), but the estimate was highly uncertain. The Otter Tail River above Breckenridge, Minn., site had the smallest concentration (about 0.6 milligram per liter). The estimated FWA concentrations for total nitrogen for the main-stem sites increased from about 0.9 milligram per liter for the Red River at Hickson, N. Dak., site to about 1.6 milligrams per liter for the Red River at Perley, Minn., site.The Sheyenne River at Harwood, N. Dak., site had the largest estimated FWA concentration for total phosphorus (about 0.5 milligram per liter). The Otter Tail River above Breckenridge, Minn., site had the smallest concentration (about 0.1 milligram per liter). The estimated FWA concentrations for total phosphorus for the main-stem sites increased from about 0.15 milligram per liter for the Red River below Wahpeton, N. Dak., site to about 0.35 milligram per liter for the Red River at Perley, Minn., site.The estimated FWA concentrations for suspended sediment for the main-stem sites increased from about 50 milligrams per liter for the Red River below Wahpeton, N. Dak., site to about 300 milligrams per liter for the Red River at Perley, Minn., site. Much of the increase occurred as a result of the large yield of suspended sediment from the Red River below Wahpeton, N. Dak., to the Red River at Hickson, N. Dak., intervening reach.

Association between photosynthesis and contrasting features of minor veins in leaves of summer annuals loading phloem via symplastic versus apoplastic routes.

PubMed

Muller, Onno; Cohu, Christopher M; Stewart, Jared J; Protheroe, Johanna A; Demmig-Adams, Barbara; Adams, William W

2014-09-01

Foliar vascular anatomy and photosynthesis were evaluated for a number of summer annual species that either load sugars into the phloem via a symplastic route (Cucumis sativus L. cv. Straight Eight; Cucurbita pepo L. cv. Italian Zucchini Romanesco; Citrullus lanatus L. cv. Faerie Hybrid; Cucurbita pepo L. cv. Autumn Gold) or an apoplastic route (Nicotiana tabacum L.; Solanum lycopersicum L. cv. Brandywine; Gossypium hirsutum L.; Helianthus annuus L. cv. Soraya), as well as winter annual apoplastic loaders (Spinacia oleracea L. cv. Giant Nobel; Arabidopsis thaliana (L.) Heynhold Col-0, Swedish and Italian ecotypes). For all summer annuals, minor vein cross-sectional xylem area and tracheid number as well as the ratio of phloem loading cells to phloem sieve elements, each when normalized for foliar vein density (VD), was correlated with photosynthesis. These links presumably reflect (1) the xylem's role in providing water to meet foliar transpirational demand supporting photosynthesis and (2) the importance of the driving force of phloem loading as well as the cross-sectional area for phloem sap flux to match foliar photosynthate production. While photosynthesis correlated with the product of VD and cross-sectional phloem cell area among symplastic loaders, photosynthesis correlated with the product of VD and phloem cell number per vein among summer annual apoplastic loaders. Phloem cell size has thus apparently been a target of selection among symplastic loaders (where loading depends on enzyme concentration within loading cells) versus phloem cell number among apoplastic loaders (where loading depends on membrane transporter numbers). © 2014 Scandinavian Plant Physiology Society.

The pricing effect of the common pattern in firm-level idiosyncratic volatility: Evidence from A-Share stocks of China

NASA Astrophysics Data System (ADS)

Su, Zhi; Shu, Tengjia; Yin, Libo

2018-05-01

Inspired by Herskovic et al. (2016), we investigate the pricing effect of the firm-level common idiosyncratic volatility (CIV) in China's A-Share market. Return tests indicate that lower CIV risk loadings bring higher returns significantly, while the pricing function of market volatility (MV) is inconsistent. Strategy that goes long the highest CIV-beta quintile and short the lowest CIV-beta quintile brings an annualized average return of 5%-7%. Our findings supplement Herskovic et al. (2016) by confirming a significantly negative relationship between CIV and stock returns in a developing market.

Continuous Passive Sampling of Solutes from Agricultural Subsurface Drainage Tubes

NASA Astrophysics Data System (ADS)

Lindblad Vendelboe, Anders; de Jonge, Hubert; Rozemeijer, Joachim; Wollesen de Jonge, Lis

2015-04-01

Agricultural subsurface tube drain systems play an important role in water and solute transport. One study, focusing on lowland agricultural catchments, showed that subsurface tube drainage contributed up to 80% of the annual discharge and 90% of the annual NO3 load from agricultural fields to the receiving water bodies. Knowledge of e.g. nutrient loads and drainage volumes, based on measurements and modelling, are important for adequate water quality management. Despite the importance of tube drain transport of solutes, monitoring data are scarce. This scarcity is a result of the existing monitoring techniques for flow and contaminant load from tube drains being expensive and labor-extensive. The study presented here aimed at developing a cheap, simple, and robust method to monitor solute loads from tube drains. The method is based on the newly developed Flowcap, which can be attached to existing tube drain outlets and can measure total flow, contaminant load and flow-averaged concentrations of solutes in the drainage. The Flowcap builds on the existing Sorbicell principle, a passive sampling system that measures average concentrations over longer periods of time (days to months) for various compounds. The Sorbicell consists of two compartments permeable to water. One compartment contains an adsorbent and one contains a tracer. When water passes through the Sorbicell the compound of interest is absorbed while a tracer is released. Using the tracer loss to calculate the volume of water that has passed the Sorbicell it is possible to calculate the average concentration of the compound. When mounting Sorbicells in the Flowcap, a flow-proportional part of the drainage is sampled from the main stream. To accommodate the wide range of drainage flow rates two Flowcaps with different capacities were tested in the laboratory: one with a capacity of 25 L min-1 (Q25) and one with a capacity of 256 L min-1 (Q256). In addition, Sorbicells with two different hydraulic resistances were tested, again to accommodate a large range of potential drainage flows rates. The experiment was continued until the Sorbicell's capacity was exhausted, which gave experimentation times from 6 to 34 days, while continuously changing the drainage flow rate to simulate field drainage conditions, and to test the range of the Flowcap. The laboratory testing yielded a very good linear correlation between drainage flow rates and Sorbicell sampling rates, giving r = 0.99 for both the Q25 and the Q256 Flowcap. The Sorbicells in this experiment were designed to measure NO3, but the Flowcap can be used with any Sorbicell and thus be used to measure any compound of interest. The Flowcap does not need housing, electricity, or maintenance and continuously register drainage volumes and contaminant loads for periods up to one month. This, in addition to the low cost of the monitoring system, enables large-scale monitoring of contaminant loads via tube drains, giving valuable data for the improvement of contaminant transport models. Further, these data will help select and evaluate the different mitigation option to improve water quality.

Stochastic evaluation of annual micropollutant loads and their uncertainties in separate storm sewers.

PubMed

Hannouche, Ali; Chebbo, Ghassan; Joannis, Claude; Gasperi, Johnny; Gromaire, Marie-Christine; Moilleron, Régis; Barraud, Sylvie; Ruban, Véronique

2017-12-01

This article describes a stochastic method to calculate the annual pollutant loads and its application over several years at the outlet of three catchments drained by separate storm sewers. A stochastic methodology using Monte Carlo simulations is proposed for assessing annual pollutant load, as well as the associated uncertainties, from a few event sampling campaigns and/or continuous turbidity measurements (representative of the total suspended solids concentration (TSS)). Indeed, in the latter case, the proposed method takes into account the correlation between pollutants and TSS. The developed method was applied to data acquired within the French research project "INOGEV" (innovations for a sustainable management of urban water) at the outlet of three urban catchments drained by separate storm sewers. Ten or so event sampling campaigns for a large range of pollutants (46 pollutants and 2 conventional water quality parameters: TSS and total organic carbon (TOC)) are combined with hundreds of rainfall events for which, at least one among three continuously monitored parameters (rainfall intensity, flow rate, and turbidity) is available. Results obtained for the three catchments show that the annual pollutant loads can be estimated with uncertainties ranging from 10 to 60%, and the added value of turbidity monitoring for lowering the uncertainty is demonstrated. A low inter-annual and inter-site variability of pollutant loads, for many of studied pollutants, is observed with respect to the estimated uncertainties, and can be explained mainly by annual precipitation.

Seasonal Mass Changes in the Red Sea Observed By GPS and Grace

NASA Astrophysics Data System (ADS)

Alothman, A. O.; Fing, W.; Fernandes, R. M. S.; Bos, M. S.; Elsaka, B.

2014-12-01

The Red Sea is a semi-enclosed basin and exchanges water with the Gulf of Aden through the strait of Bab-el-Mandeb at the southern part of the sea. Its circulation is affected by the Indian Monsoon through its connection via the Gulf of Aden. Two distinctive (in summer and in winter) seasonal signals represent the water exchange. To understand the seasonal mass changes in the Red Sea, estimates of the mass changes based on two geodetic techniques are presented: from the Gravity Recovery and Climate Experiment (GRACE) and from the Global Navigation Satellite System (GNSS). The GRACE solutions were truncated up to spherical harmonic degree and order degree 60 to estimate the average monthly mass change in the atmosphere and ocean from models (several hours). GNSS solution is based on observations from four stations along the Red Sea that have been acquired in continuous mode starting in 2007 (having at least 5 years' data-span). The time series analysis of the observed GNSS vertical deformation of these sites has been analyzed. The results revealed that the GNSS observed vertical loading agrees with the atmospheric loading (ATML) assuming that the hydrological signal along the costs of the Red sea is negligible. Computed values of daily vertical atmospheric loading using the NCEP surface pressure data (Inverted Barometer IB) for the 4 stations for 2003 until 2013 are provided. Comparison of the GRACE and GNSS solutions has shown significant annual mass variations in the Red Sea (about 15 cm annual amplitude). After removing the atmospheric effect (ATML), the ocean loading can be observed by GNSS and GRACE estimates in the Red Sea.

50 CFR 218.171 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

...); (2) Northern fur seal (Callorhinus ursinus)—220 (an average of 44 annually); (3) California sea lion (Zalophus californianus)—570 (an average of 114 annually); (4) Northern elephant seal (Mirounga angustirostris)—70 (an average of 14 annually); (5) Harbor seal (Phoca vitulina richardsi) (Washington Inland...

Large-scale suspended sediment transport and sediment deposition in the Mekong Delta

NASA Astrophysics Data System (ADS)

Manh, N. V.; Dung, N. V.; Hung, N. N.; Merz, B.; Apel, H.

2014-08-01

Sediment dynamics play a major role in the agricultural and fishery productivity of the Mekong Delta. However, the understanding of sediment dynamics in the delta, one of the most complex river deltas in the world, is very limited. This is a consequence of its large extent, the intricate system of rivers, channels and floodplains, and the scarcity of observations. This study quantifies, for the first time, the suspended sediment transport and sediment deposition in the whole Mekong Delta. To this end, a quasi-2D hydrodynamic model is combined with a cohesive sediment transport model. The combined model is calibrated using six objective functions to represent the different aspects of the hydraulic and sediment transport components. The model is calibrated for the extreme flood season in 2011 and shows good performance for 2 validation years with very different flood characteristics. It is shown how sediment transport and sediment deposition is differentiated from Kratie at the entrance of the delta on its way to the coast. The main factors influencing the spatial sediment dynamics are the river and channel system, dike rings, sluice gate operations, the magnitude of the floods, and tidal influences. The superposition of these factors leads to high spatial variability of sediment transport, in particular in the Vietnamese floodplains. Depending on the flood magnitude, annual sediment loads reaching the coast vary from 48 to 60% of the sediment load at Kratie. Deposited sediment varies from 19 to 23% of the annual load at Kratie in Cambodian floodplains, and from 1 to 6% in the compartmented and diked floodplains in Vietnam. Annual deposited nutrients (N, P, K), which are associated with the sediment deposition, provide on average more than 50% of mineral fertilizers typically applied for rice crops in non-flooded ring dike floodplains in Vietnam. Through the quantification of sediment and related nutrient input, the presented study provides a quantitative basis for estimating the benefits of annual Mekong floods for agriculture and fishery, and is an important piece of information with regard to the assessment of the impacts of deltaic subsidence and climate-change-related sea level rise on delta morphology.

Hydrologically-driven crustal stresses and seismicity in the New Madrid Seismic Zone.

PubMed

Craig, Timothy J; Chanard, Kristel; Calais, Eric

2017-12-15

The degree to which short-term non-tectonic processes, either natural and anthropogenic, influence the occurrence of earthquakes in active tectonic settings or 'stable' plate interiors, remains a subject of debate. Recent work in plate-boundary regions demonstrates the capacity for long-wavelength changes in continental water storage to produce observable surface deformation, induce crustal stresses and modulate seismicity rates. Here we show that a significant variation in the rate of microearthquakes in the intraplate New Madrid Seismic Zone at annual and multi-annual timescales coincides with hydrological loading in the upper Mississippi embayment. We demonstrate that this loading, which results in geodetically observed surface deformation, induces stresses within the lithosphere that, although of small amplitude, modulate the ongoing seismicity of the New Madrid region. Correspondence between surface deformation, hydrological loading and seismicity rates at both annual and multi-annual timescales indicates that seismicity variations are the direct result of elastic stresses induced by the water load.

50 CFR 216.272 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

... electra)—100 (an average of 20 annually) (S) Pygmy killer whale (Feresa attenuata)—100 (an average of 20 annually) (T) False killer whale (Pseudorca crassidens)—100 (an average of 20 annually) (U) Killer whale... percent of the number of takes indicated below): (i) Mysticetes: (A) Humpback whale (Megaptera...

50 CFR 217.142 - Permissible methods of taking.

Code of Federal Regulations, 2014 CFR

2014-10-01

... method and amount of take: (1) Level B Harassment: (i) Cetaceans: (A) Bowhead whale (Balaena mysticetus)—75 (an average of 15 annually) (B) Gray whale (Eschrichtius robustus)—10 (an average of 2 annually) (C) Beluga whale (Delphinapterus leucas)—100 (an average of 20 annually) (ii) Pinnipeds: (A) Ringed...

Concentrations, loads, and yields of total nitrogen and total phosphorus in the Barnegat Bay-Little Egg Harbor watershed, New Jersey, 1989-2011, at multiple spatial scales

USGS Publications Warehouse

Baker, Ronald J.; Wieben, Christine M.; Lathrop, Richard G.; Nicholson, Robert S.

2014-01-01

Concentrations, loads, and yields of nutrients (total nitrogen and total phosphorus) were calculated for the Barnegat Bay-Little Egg Harbor (BB-LEH) watershed for 1989–2011 at annual and seasonal (growing and nongrowing) time scales. Concentrations, loads, and yields were calculated at three spatial scales: for each of the 81 subbasins specified by 14-digit hydrologic unit codes (HUC-14s); for each of the three BB-LEH watershed segments, which coincide with segmentation of the BB-LEH estuary; and for the entire BB-LEH watershed. Base-flow and runoff values were calculated separately and were combined to provide total values. Available surface-water-quality data for all streams in the BB-LEH watershed for 1980–2011 were compiled from existing datasets and quality assured. Precipitation and streamflow data were used to distinguish between water-quality samples that were collected during base-flow conditions and those that were collected during runoff conditions. Base-flow separation of hydrographs of six streams in the BB-LEH watershed indicated that base flow accounts for about 72 to 94 percent of total flow in streams in the watershed. Base-flow mean concentrations (BMCs) of total nitrogen (TN) and total phosphorus (TP) for each HUC-14 subbasin were calculated from relations between land use and measured base-flow concentrations. These relations were developed from multiple linear regression models determined from water-quality data collected at sampling stations in the BB-LEH watershed under base-flow conditions and land-use percentages in the contributing drainage basins. The total watershed base-flow volume was estimated for each year and season from continuous streamflow records for 1989–2011 and relations between precipitation and streamflow during base-flow conditions. For each year and season, the base-flow load and yield were then calculated for each HUC-14 subbasin from the BMCs, total base-flow volume, and drainage area. The watershed-loading application PLOAD was used to calculate runoff concentrations, loads, and yields of TN and TP at the HUC-14 scale. Flow-weighted event-mean concentrations (EMCs) for runoff were developed for each major land-use type in the watershed using storm sampling data from four streams in the BB-LEH watershed and three streams outside the watershed. The EMCs were developed separately for the growing and nongrowing seasons, and were typically greater during the growing season. The EMCs, along with annual and seasonal precipitation amounts and percent imperviousness associated with land-use types, were used as inputs to PLOAD to calculate annual and seasonal runoff concentrations, loads, and yields at the HUC-14 scale. Over the period of study (1989–2011), total surface-water loads (base flow plus runoff) for the entire BB-LEH watershed for TN ranged from about 455,000 kilograms (kg) as N (1995) to 857,000 kg as N (2010). For TP, total loads for the watershed ranged from about 17,000 (1995) to 32,000 kg as P (2010). On average, the north segment accounted for about 66 percent of the annual TN load and 63 percent of the annual TP load, and the central and south segments each accounted for less than 20 percent of the nutrient loads. Loads and yields were strongly associated with precipitation patterns, ensuing hydrologic conditions, and land use. HUC-14 subbasins with the highest yields of nutrients are concentrated in the northern part of the watershed, and have the highest percentages of urban or agricultural land use. Subbasins with the lowest TN and TP yields are dominated by forest cover. Percentages of turf (lawn) cover and nonturf cover were estimated for the watershed. Of the developed land in the watershed, nearly one quarter (24.9 percent) was mapped as turf cover. Because there is a strong relation between percent turf and percent developed land, percent turf in the watershed typically increases with percent development, and the amount of development can be considered a reasonable predictor of the amount of turf cover in the watershed. In the BB-LEH watershed, calculated concentrations of TN and TP were greater for developed–turf areas than for developed–nonturf areas, which, in turn, were greater than those for undeveloped areas.

Effects of internal gain assumptions in building energy calculations

NASA Astrophysics Data System (ADS)

Christensen, C.; Perkins, R.

1981-01-01

The utilization of direct solar gains in buildings can be affected by operating profiles, such as schedules for internal gains, thermostat controls, and ventilation rates. Building energy analysis methods use various assumptions about these profiles. The effects of typical internal gain assumptions in energy calculations are described. Heating and cooling loads from simulations using the DOE 2.1 computer code are compared for various internal gain inputs: typical hourly profiles, constant average profiles, and zero gain profiles. Prototype single-family-detached and multifamily-attached residential units are studied with various levels of insulation and infiltration. Small detached commercial buildings and attached zones in large commercial buildings are studied with various levels of internal gains. The results indicate that calculations of annual heating and cooling loads are sensitive to internal gains, but in most cases are relatively insensitive to hourly variations in internal gains.

Evaluating water quality ecosystem services of wetlands under historic and future climate

NASA Astrophysics Data System (ADS)

Records, R.; Arabi, M.; Fassnacht, S. R.; Duffy, W.; Ahmadi, M.; Hegewisch, K.

2013-12-01

Potential hydrologic effects of climate change have been assessed extensively; however, possible impacts of changing climate on in-stream water quality at the watershed scale have received little study. We assessed potential impacts of climate change on water quantity and quality in the mountainous Sprague River watershed, Oregon, USA, where high total phosphorus (TP) and sediment loads are associated with lake eutrophication and mortality of endangered fish species. Additionally, we analyzed water quality impacts of wetland and riparian zone loss and gain under present-day climate and future climate scenarios. We utilized the hydrologic model Soil and Water Assessment Tool (SWAT) forced with six distinct climate scenarios derived from Coupled Model Intercomparison Project 5 (CMIP5) General Circulation Models to assess magnitude and direction of trends in streamflow, sediment and TP fluxes in the mid-21st century (2030-2059). Model results showed little significant trend in average annual streamflow under most climate scenarios, but trends in annual and monthly streamflow, sediment, and TP fluxes were more pronounced and were generally increasing. Results also suggest that future loss of present-day wetlands and riparian zones under land use or climatic change could result in substantial increases in sediment and TP loads at the Sprague River outlet.

The changing trend in nitrate concentrations in major aquifers due to historical nitrate loading from agricultural land across England and Wales from 1925 to 2150.

PubMed

Wang, L; Stuart, M E; Lewis, M A; Ward, R S; Skirvin, D; Naden, P S; Collins, A L; Ascott, M J

2016-01-15

Nitrate is necessary for agricultural productivity, but can cause considerable problems if released into aquatic systems. Agricultural land is the major source of nitrates in UK groundwater. Due to the long time-lag in the groundwater system, it could take decades for leached nitrate from the soil to discharge into freshwaters. However, this nitrate time-lag has rarely been considered in environmental water management. Against this background, this paper presents an approach to modelling groundwater nitrate at the national scale, to simulate the impacts of historical nitrate loading from agricultural land on the evolution of groundwater nitrate concentrations. An additional process-based component was constructed for the saturated zone of significant aquifers in England and Wales. This uses a simple flow model which requires modelled recharge values, together with published aquifer properties and thickness data. A spatially distributed and temporally variable nitrate input function was also introduced. The sensitivity of parameters was analysed using Monte Carlo simulations. The model was calibrated using national nitrate monitoring data. Time series of annual average nitrate concentrations along with annual spatially distributed nitrate concentration maps from 1925 to 2150 were generated for 28 selected aquifer zones. The results show that 16 aquifer zones have an increasing trend in nitrate concentration, while average nitrate concentrations in the remaining 12 are declining. The results are also indicative of the trend in the flux of groundwater nitrate entering rivers through baseflow. The model thus enables the magnitude and timescale of groundwater nitrate response to be factored into source apportionment tools and to be taken into account alongside current planning of land-management options for reducing nitrate losses. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Continental Scale Aerosol Optical Properties Over East Asia as Measured by Aeronet and Comparison to Satellite and Modeled Results

NASA Technical Reports Server (NTRS)

Holben, B. N.; Eck, T.; Smirnov, A.; Sinyuk, A.; Dubovik, O.; Slutsker, I.; Giles, D.; Sorokine, M.; Chin, L.; Remer, P.;

Operation and Equivalent Loads of Wind Turbines in Large Wind Farms

NASA Astrophysics Data System (ADS)

Andersen, Soren Juhl; Sorensen, Jens Norkaer; Mikkelsen, Robert Flemming

2017-11-01

Wind farms continue to grow in size and as the technology matures, the design of wind farms move towards including dynamic effects besides merely annual power production estimates. The unsteady operation of wind turbines in large wind farms has been modelled with EllipSys3D(Michelsen, 1992, and Sørensen, 1995) for a number of different scenarios using a fully coupled large eddy simulations(LES) and aero-elastic framework. The turbines are represented in the flow fields using the actuator line method(Sørensen and Shen, 2002), where the aerodynamic forces and deflections are derived from an aero-elastic code, Flex5(Øye, 1996). The simulations constitute a database of full turbine operation in terms of both production and loads for various wind speeds, turbulence intensities, and turbine spacings. The operating conditions are examined in terms of averaged power production and thrust force, as well as 10min equivalent flapwise bending, yaw, and tilt moment loads. The analyses focus on how the performance and loads change throughout a given farm as well as comparing how various input parameters affect the operation and loads of the wind turbines during different scenarios. COMWIND(Grant 2104-09- 067216/DSF), Nordic Consortium on Optimization and Control of Wind Farms, Eurotech Greentech Wind project, Winds2Loads, and CCA LES. Ressources Granted on SNIC and JESS. The Vestas NM80 turbine has been used.

Submarine groundwater discharge and nutrient loadings in Tolo Harbor, Hong Kong using multiple geotracer-based models, and their implications of red tide outbreaks.

PubMed

Luo, Xin; Jiao, Jiu Jimmy

2016-10-01

Multiple tracers, including radium quartet, (222)Rn and silica are used to quantify submarine groundwater discharge (SGD) into Tolo Harbor, Hong Kong in 2005 and 2011. Five geotracer models based on the end member model of (228)Ra and salinity and mass balance models of (226)Ra, (228)Ra, (222)Rn, and silica were established and all the models lead to an estimate of the SGD rate of the same order of magnitude. In 2005 and 2011, respectively, the averaged SGD based on these models is estimated to be ≈ 5.42 cm d(-1) and ≈2.66 cm d(-1), the SGD derived DIN loadings to be 3.5 × 10(5) mol d(-1) and 1.5 × 10(5) mol d(-1), and DIP loadings to be 6.2 × 10(3) mol d(-1) and 1.1 × 10(3) mol d(-1). Groundwater borne nutrients are 1-2 orders of magnitude larger than other nutrient sources and the interannual variation of nutrient concentration in the embayment is more influenced by the SGD derived loadings. Annual DIP concentrations in the harbor water is positively correlated with the precipitation and annual mean tidal range, and negatively correlated with evapotranspiration from 2000 to 2013. Climatologically driven SGD variability alters the SGD derived DIP loadings in this phosphate limited environment and may be the causative factor of interannual variability of red tide outbreaks from 2000 to 2013. Finally, a conceptual model is proposed to characterize the response of red tide outbreaks to climatological factors linked by SGD. The findings from this study shed light on the prediction of red tide outbreaks and coastal management of Tolo Harbor and similar coastal embayments elsewhere. Copyright © 2016 Elsevier Ltd. All rights reserved.

Organic carbon and nitrogen concentrations and annual organic carbon load of six selected rivers of the United States

USGS Publications Warehouse

Malcolm, R.L.; Durum, W.H.

1976-01-01

The organic carbon load during 1969-70 of each of the six rivers in this study is substantial. The 3.4-billion-kilogram (3.7-million-ton) and 47-million-kilogram (52-thousandton) annual organic carbon loads of the Mississippi River and the Brazos River (Tex.), respectively, were approximately equally distributed between dissolved and suspended phases, whereas the 725-million-kilogram (79.8-million-ton) organic load of the Missouri River was primarily in the suspended phase. The major portion of the 6.4-million-kilogram (7.3 thousand-ton) and the 19-million-kilogram (21-thousand-ton) organic carbon loads of the Sopchoppy River (Fla.) and the Neuse River (N.C.), respectively, was in the dissolved phase. DOC (dissolved organic carbon) concentrations in most rivers were usually less than 8 milligrams per litre. SOC (suspended organic carbon) concentrations fluctuated markedly with discharge, ranging between 1 and 14 percent, by weight, in sediment of most rivers. DOC concentrations were found to be independent of discharge, whereas SOC and SIC (suspended inorganic carbon) concentrations were positively correlated with discharge. Seasonal fluctuations in DOC and SOC were exhibited by the Missouri, Neuse, Ohio, and Brazos Rivers, but both SOC and DOC concentrations were relatively constant throughout the year in the Mississippi and Sopchoppy Rivers. The carbon-nitrogen ratio in the sediment phase of all river waters averaged less than 8 1 as compared with 12:1 or greater for most soils. This high nitrogen content shows a nitrogen enrichment of the stream sediment over that in adjacent soils, which suggests that different decomposition and humification processes are operating in streams than in the soils. The abundance of organic material in the dissolved and suspended phase of all river waters in this study indicate a large capacity factor for various types of organic reactivity within all streams and the quantitative importance of organic constituents in relation to the water quality of rivers and streams.

7 CFR Appendix A to Subpart B of... - Review Rating Summary, RUS Form 300

Code of Federal Regulations, 2014 CFR

2014-01-01

.... System Load Conditions and Losses a. Annual System Loses, ____%—Rating:____ b. Annual Load Factor... ____ Date Prepared ____ Ratings on form are: 0: Unsatisfactory—no records 1: Unsatisfactory—corrective action needed 2: Acceptable, but should be improved—see attached recommendations 3: Satisfactory—no...

Character and Trends of Water Quality in the Blue River Basin, Kansas City Metropolitan Area, Missouri and Kansas, 1998 through 2007

USGS Publications Warehouse

Wilkison, Donald H.; Armstrong, Daniel J.; Hampton, Sarah A.

2009-01-01

Water-quality and ecological character and trends in the metropolitan Blue River Basin were evaluated from 1998 through 2007 to provide spatial and temporal resolution to factors that affect the quality of water and biota in the basin and provide a basis for assessing the efficacy of long-term combined sewer control and basin management plans. Assessments included measurements of stream discharge, pH, dissolved oxygen, specific conductance, turbidity, nutrients (dissolved and total nitrogen and phosphorus species), fecal-indicator bacteria (Escherichia coli and fecal coliform), suspended sediment, organic wastewater and pharmaceutical compounds, and sources of these compounds as well as the quality of stream biota in the basin. Because of the nature and myriad of factors that affect basin water quality, multiple strategies are needed to decrease constituent loads in streams. Strategies designed to decrease or eliminate combined sewer overflows (CSOs) would substantially reduce the annual loads of nutrients and fecal-indicator bacteria in Brush Creek, but have little effect on Blue River loadings. Nonpoint source reductions to Brush Creek could potentially have an equivalent, if not greater, effect on water quality than would CSO reductions. Nonpoint source reductions could also substantially decrease annual nutrient and bacteria loadings to the Blue River and Indian Creek. Methods designed to decrease nutrient loads originating from Blue River and Indian Creek wastewater treatment plants (WWTPs) could substantially reduce the overall nutrient load in these streams. For the main stem of the Blue River and Indian Creek, primary sources of nutrients were nonpoint source runoff and WWTPs discharges; however, the relative contribution of each source varied depending on how wet or dry the year was and the number of upstream WWTPs. On Brush Creek, approximately two-thirds of the nutrients originated from nonpoint sources and the remainder from CSOs. Nutrient assimilation processes, which reduced total nitrogen loads by approximately 13 percent and total phosphorus loads by double that amount in a 20-kilometer reach of the Blue River during three synoptic base-flow sampling events between August through September 2004 and September 2005, likely are limited to selected periods during any given year and may not substantially reduce annual nutrient loads. Bacteria densities typically increased with increasing urbanization, and bacteria loadings to the Blue River and Indian Creek were almost entirely the result of nonpoint source runoff. WWTPs contributed, on average, less than 1 percent of the bacteria to these reaches, and in areas of the Blue River that had combined sewers, CSOs contributed only minor amounts (less than 2 percent) of the total annual load in 2005. The bulk of the fecal-indicator bacteria load in Brush Creek also originated from nonpoint sources with the remainder from CSOs. From October 2002 through September 2007, estimated daily mean Escherichia coli bacteria density in upper reaches of the Blue River met the State of Missouri secondary contact criterion standard approximately 85 percent of the time. However, in lower Blue River reaches, the same threshold was exceeded approximately 45 percent of the time. The tributary with the greatest number of CSO discharge points, Brush Creek, contributed approximately 10 percent of the bacteria loads to downstream reaches. The tributary Town Fork Creek had median base-flow Escherichia coli densities that were double that of other basin sites and stormflow densities 10 times greater than those in other parts of the basin largely because approximately one-fourth of the runoff in the Town Fork Creek Basin is believed to originate in combined sewers. Genotypic source typing of bacteria indicated that more than half of the bacteria in this tributary originated from human sources with two storms contributing the bulk of all bacteria sourced as human. However, areas outsid

Continuous real-time water-quality monitoring and regression analysis to compute constituent concentrations and loads in the North Fork Ninnescah River upstream from Cheney Reservoir, south-central Kansas, 1999–2012

USGS Publications Warehouse

Stone, Mandy L.; Graham, Jennifer L.; Gatotho, Jackline W.

2013-01-01

Cheney Reservoir, located in south-central Kansas, is the primary water supply for the city of Wichita. The U.S. Geological Survey has operated a continuous real-time water-quality monitoring station since 1998 on the North Fork Ninnescah River, the main source of inflow to Cheney Reservoir. Continuously measured water-quality physical properties include streamflow, specific conductance, pH, water temperature, dissolved oxygen, and turbidity. Discrete water-quality samples were collected during 1999 through 2009 and analyzed for sediment, nutrients, bacteria, and other water-quality constituents. Regression models were developed to establish relations between discretely sampled constituent concentrations and continuously measured physical properties to compute concentrations of those constituents of interest that are not easily measured in real time because of limitations in sensor technology and fiscal constraints. Regression models were published in 2006 that were based on data collected during 1997 through 2003. This report updates those models using discrete and continuous data collected during January 1999 through December 2009. Models also were developed for four new constituents, including additional nutrient species and indicator bacteria. In addition, a conversion factor of 0.68 was established to convert the Yellow Springs Instruments (YSI) model 6026 turbidity sensor measurements to the newer YSI model 6136 sensor at the North Ninnescah River upstream from Cheney Reservoir site. Newly developed models and 14 years of hourly continuously measured data were used to calculate selected constituent concentrations and loads during January 1999 through December 2012. The water-quality information in this report is important to the city of Wichita because it allows the concentrations of many potential pollutants of interest to Cheney Reservoir, including nutrients and sediment, to be estimated in real time and characterized over conditions and time scales that would not be possible otherwise. In general, model forms and the amount of variance explained by the models was similar between the original and updated models. The amount of variance explained by the updated models changed by 10 percent or less relative to the original models. Total nitrogen, nitrate, organic nitrogen, E. coli bacteria, and total organic carbon models were newly developed for this report. Additional data collection over a wider range of hydrological conditions facilitated the development of these models. The nitrate model is particularly important because it allows for comparison to Cheney Reservoir Task Force goals. Mean hourly computed total suspended solids concentration during 1999 through 2012 was 54 milligrams per liter (mg/L). The total suspended solids load during 1999 through 2012 was 174,031 tons. On an average annual basis, the Cheney Reservoir Task Force runoff (550 mg/L) and long-term (100 mg/L) total suspended solids goals were never exceeded, but the base flow goal was exceeded every year during 1999 through 2012. Mean hourly computed nitrate concentration was 1.08 mg/L during 1999 through 2012. The total nitrate load during 1999 through 2012 was 1,361 tons. On an annual average basis, the Cheney Reservoir Task Force runoff (6.60 mg/L) nitrate goal was never exceeded, the long-term goal (1.20 mg/L) was exceeded only in 2012, and the base flow goal of 0.25 mg/L was exceeded every year. Mean nitrate concentrations that were higher during base flow, rather than during runoff conditions, suggest that groundwater sources are the main contributors of nitrate to the North Fork Ninnescah River above Cheney Reservoir. Mean hourly computed phosphorus concentration was 0.14 mg/L during 1999 through 2012. The total phosphorus load during 1999 through 2012 was 328 tons. On an average annual basis, the Cheney Reservoir Task Force runoff goal of 0.40 mg/L for total phosphorus was exceeded in 2002, the year with the largest yearly mean turbidity, and the long-term goal (0.10 mg/L) was exceeded in every year except 2011 and 2012, the years with the smallest mean streamflows. The total phosphorus base flow goal of 0.05 mg/L was exceeded every year. Given that base flow goals for total suspended solids, nitrate, and total phosphorus were exceeded every year despite hydrologic conditions, the established base flow goals are either unattainable or substantially more best management practices will need to be implemented to attain them. On an annual average basis, no discernible patterns were evident in total suspended sediment, nitrate, and total phosphorus concentrations or loads over time, in large part because of hydrologic variability. However, more rigorous statistical analyses are required to evaluate temporal trends. A more rigorous analysis of temporal trends will allow evaluation of watershed investments in best management practices.

50 CFR 218.102 - Permissible methods of taking.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Odontocetes: (A) Sperm whales (Physeter macrocephalus)—4,120 (an average of 824 annually); (B) Killer whale...) Melon-headed whale (Peponocephala electra)—14,315 (an average of 2,863 annually); (J) Pygmy killer whale (Feresa attenuata)—800 (an average of 160 annually); (K) False killer whale (Pseudorca crassidens)—6,445...

50 CFR 218.102 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Odontocetes: (A) Sperm whales (Physeter macrocephalus)—4,120 (an average of 824 annually); (B) Killer whale...) Melon-headed whale (Peponocephala electra)—14,315 (an average of 2,863 annually); (J) Pygmy killer whale (Feresa attenuata)—800 (an average of 160 annually); (K) False killer whale (Pseudorca crassidens)—6,445...

50 CFR 218.102 - Permissible methods of taking.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Odontocetes: (A) Sperm whales (Physeter macrocephalus)—4,120 (an average of 824 annually); (B) Killer whale...) Melon-headed whale (Peponocephala electra)—14,315 (an average of 2,863 annually); (J) Pygmy killer whale (Feresa attenuata)—800 (an average of 160 annually); (K) False killer whale (Pseudorca crassidens)—6,445...

50 CFR 218.102 - Permissible methods of taking.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Odontocetes: (A) Sperm whales (Physeter macrocephalus)—4,120 (an average of 824 annually); (B) Killer whale...) Melon-headed whale (Peponocephala electra)—14,315 (an average of 2,863 annually); (J) Pygmy killer whale (Feresa attenuata)—800 (an average of 160 annually); (K) False killer whale (Pseudorca crassidens)—6,445...

50 CFR 218.2 - Permissible methods of taking.

Code of Federal Regulations, 2010 CFR

2010-10-01

...: (i) Mysticetes: (A) Humpback whale (Megaptera novaeangliae)—10 (an average of 2 annually); and (B) Fin whale (Balaenoptera physalus)—10 (an average of 2 annually). (ii) Odontocetes: (A) Sperm whale (Physeter macrocephalus)—10 (an average of 2 annually); (B) Pygmy or dwarf sperm whales (Kogia sp.)—15 (an...

50 CFR 218.2 - Permissible methods of taking.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: (i) Mysticetes: (A) Humpback whale (Megaptera novaeangliae)—10 (an average of 2 annually); and (B) Fin whale (Balaenoptera physalus)—10 (an average of 2 annually). (ii) Odontocetes: (A) Sperm whale (Physeter macrocephalus)—10 (an average of 2 annually); (B) Pygmy or dwarf sperm whales (Kogia sp.)—15 (an...

50 CFR 218.2 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: (i) Mysticetes: (A) Humpback whale (Megaptera novaeangliae)—10 (an average of 2 annually); and (B) Fin whale (Balaenoptera physalus)—10 (an average of 2 annually). (ii) Odontocetes: (A) Sperm whale (Physeter macrocephalus)—10 (an average of 2 annually); (B) Pygmy or dwarf sperm whales (Kogia sp.)—15 (an...

Characteristics of nitrogen loading and its influencing factors in several typical agricultural watersheds of subtropical China.

PubMed

Li, Yuyuan; Jiao, Junxia; Wang, Yi; Yang, Wen; Meng, Cen; Li, Baozhen; Li, Yong; Wu, Jinshui

2015-02-01

Increasingly, the characteristics of nitrogen (N) loading have been recognized to be critical for the maintenance and restoration of water quality in agricultural watersheds, in response to the spread of water eutrophication. This paper estimates N loading and investigates its influencing factors in ten small watersheds variously dominated by forest and agricultural land use types in the subtropics of China, over an observation period of 23-29 months. The results indicate that the average concentrations of total nitrogen (TN), NH4 (+)-N, and NO3 (-)-N were 0.83, 0.07, and 0.46 mg N L(-1) in the forest watersheds and 1.49-5.16, 0.21-3.23, and 0.99-1.30 mg N L(-1) in the agricultural watersheds, respectively. Such concentrations exceed the national criteria for nutrient pollution in surface waters considerably, suggesting severe stream pollution in the studied agricultural watersheds. The average annual TN loadings (ANL) were estimated to be 1,640.8 kg N km(-2) year(-1) in the agricultural watersheds, 63.3-86.1 % of which was composed of dissolved inorganic N (DIN; comprising NO3 (-)-N and NH4 (+)-N). The watershed with intensive livestock production (i.e., the maximum livestock density of 2.66 animal units (AU) ha(-1)) exhibited the highest ANL (2,928.7 kg N km(-2) year(-1)) related to N loss with effluent discharge. The results of correlation and principle component analysis suggest that livestock production was the dominant influencing factor for the TN and NH4 (+)-N loadings and that the percentages of cropland in watersheds can significantly increase the NO3 (-)-N loading in agricultural watersheds. Therefore, to restore and maintain water quality, animal production regulations and more careful planning of land use are necessary in the agricultural watersheds of subtropical China.

Watershed Regressions for Pesticides (WARP) for Predicting Annual Maximum and Annual Maximum Moving-Average Concentrations of Atrazine in Streams

USGS Publications Warehouse

Stone, Wesley W.; Gilliom, Robert J.; Crawford, Charles G.

2008-01-01

Regression models were developed for predicting annual maximum and selected annual maximum moving-average concentrations of atrazine in streams using the Watershed Regressions for Pesticides (WARP) methodology developed by the National Water-Quality Assessment Program (NAWQA) of the U.S. Geological Survey (USGS). The current effort builds on the original WARP models, which were based on the annual mean and selected percentiles of the annual frequency distribution of atrazine concentrations. Estimates of annual maximum and annual maximum moving-average concentrations for selected durations are needed to characterize the levels of atrazine and other pesticides for comparison to specific water-quality benchmarks for evaluation of potential concerns regarding human health or aquatic life. Separate regression models were derived for the annual maximum and annual maximum 21-day, 60-day, and 90-day moving-average concentrations. Development of the regression models used the same explanatory variables, transformations, model development data, model validation data, and regression methods as those used in the original development of WARP. The models accounted for 72 to 75 percent of the variability in the concentration statistics among the 112 sampling sites used for model development. Predicted concentration statistics from the four models were within a factor of 10 of the observed concentration statistics for most of the model development and validation sites. Overall, performance of the models for the development and validation sites supports the application of the WARP models for predicting annual maximum and selected annual maximum moving-average atrazine concentration in streams and provides a framework to interpret the predictions in terms of uncertainty. For streams with inadequate direct measurements of atrazine concentrations, the WARP model predictions for the annual maximum and the annual maximum moving-average atrazine concentrations can be used to characterize the probable levels of atrazine for comparison to specific water-quality benchmarks. Sites with a high probability of exceeding a benchmark for human health or aquatic life can be prioritized for monitoring.

Estimation of average annual streamflows and power potentials for Alaska and Hawaii

DOE Office of Scientific and Technical Information (OSTI.GOV)

Verdin, Kristine L.

2004-05-01

This paper describes the work done to develop average annual streamflow estimates and power potential for the states of Alaska and Hawaii. The Elevation Derivatives for National Applications (EDNA) database was used, along with climatic datasets, to develop flow and power estimates for every stream reach in the EDNA database. Estimates of average annual streamflows were derived using state-specific regression equations, which were functions of average annual precipitation, precipitation intensity, drainage area, and other elevation-derived parameters. Power potential was calculated through the use of the average annual streamflow and the hydraulic head of each reach, which is calculated from themore » EDNA digital elevation model. In all, estimates of streamflow and power potential were calculated for over 170,000 stream segments in the Alaskan and Hawaiian datasets.« less

Estimated Loads of Suspended Sediment and Selected Trace Elements Transported through Milltown Reservoir in the Upper Clark Fork Basin, Montana, Water Years 2004-07

USGS Publications Warehouse

Lambing, John H.; Sando, Steven K.

2008-01-01

The purpose of this report is to present estimated daily and annual loads of suspended sediment and selected trace elements for water years 2004-07 at two sites upstream and one site downstream from Milltown Reservoir. Milltown Reservoir is a National Priorities List Superfund site in the upper Clark Fork basin of western Montana where sediments enriched in trace elements from historical mining and ore processing have been deposited since the construction of Milltown Dam in 1907. The estimated loads were used to quantify annual net gains and losses (mass balance) of suspended sediment and trace elements within Milltown Reservoir before and after June 1, 2006, which was the start of Stage 1 of a permanent drawdown of the reservoir in preparation for removal of Milltown Dam. This study was done in cooperation with the U.S. Environmental Protection Agency. Daily loads of suspended sediment were estimated for water years 2004-07 by using either high-frequency sampling as part of daily sediment monitoring or regression equations relating suspended-sediment discharge to streamflow. Daily loads of unfiltered-recoverable arsenic, cadmium, copper, iron, lead, manganese, and zinc were estimated by using regression equations relating trace-element discharge to suspended-sediment discharge. Regression equations were developed from data for eriodic water-quality samples collected during water years 2004-07. The equations were applied to daily records of either streamflow or suspended-sediment discharge to produce estimated daily loads. Variations in daily suspended-sediment and trace-element loads generally coincided with variations in streamflow. For most of the period before June 1, 2006, differences in daily loads transported to and from Milltown Reservoir were minor or indicated small amounts of deposition; however, losses of suspended sediment and trace elements from the reservoir occurred during temporary drawdowns in July-August 2004 and October-December 2005. After the start of Stage 1 of the permanent drawdown on June 1, 2006, losses of suspended sediment and trace elements from the reservoir persisted for all streamflow conditions during the entire interval of the Stage 1 drawdown (June 1, 2006-September 30, 2007) within the study period. Estimated daily loads of suspended sediment and trace elements were summed for each year to produce estimated annual loads used to determine the annual net gains (deposition) or losses (erosion) of each constituent within Milltown Reservoir during water years 2004-07. During water year 2004, there was an annual net gain of suspended sediment in the reservoir. The annual net gains and losses of trace elements were inconsistent in water year 2004, with gains occurring for arsenic ad iron, but losses occurring for cadmium, copper, lead, manganese, and zinc. In water year 2005, there were annual net gains of suspended sediment and all the trace elements within the reservoir. In water year 2006, there were annual net losses of all constituents from the reservoir, likely as the result of sediment erosion from the reservoir during both a temporary drawdown in October-December 2005 and Stage 1 of the permanent drawdown that continued after June 1, 2006. In water year 2007, when the Stage 1 drawdown was in effect for the entire year, there were large annual net losses of suspended sediment and trace elements from the reservoir. The annual net losses of constituents from Milltown Reservoir in water year 2007 were the largest of any year during the 2004-07 study period. In water year 2007, the annual net loss of suspended sediment from the reservoir was 130,000 tons, which was more than double (about 222 percent) the combined inflow to the reservoir. The largest annual net losses of trace elements in water year 2007, in percent of the combined inflow to the reservoir, occurred for cadmium, copper, lead, and zinc-about 190 percent for cadmium, 170 percent for copper, 150 percent for lead, and 238 p

39 CFR 3010.21 - Calculation of annual limitation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... notice of rate adjustment and dividing the sum by 12 (Recent Average). Then, a second simple average CPI... Recent Average and dividing the sum by 12 (Base Average). Finally, the annual limitation is calculated by dividing the Recent Average by the Base Average and subtracting 1 from the quotient. The result is...

39 CFR 3010.21 - Calculation of annual limitation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... notice of rate adjustment and dividing the sum by 12 (Recent Average). Then, a second simple average CPI... Recent Average and dividing the sum by 12 (Base Average). Finally, the annual limitation is calculated by dividing the Recent Average by the Base Average and subtracting 1 from the quotient. The result is...

39 CFR 3010.21 - Calculation of annual limitation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... notice of rate adjustment and dividing the sum by 12 (Recent Average). Then, a second simple average CPI... Recent Average and dividing the sum by 12 (Base Average). Finally, the annual limitation is calculated by dividing the Recent Average by the Base Average and subtracting 1 from the quotient. The result is...

Temporal and spatial trends in nutrient and sediment loading to Lake Tahoe, California-Nevada, USA

USGS Publications Warehouse

Coats, Robert; Lewis, Jack; Alvarez, Nancy L.; Arneson, Patricia

2016-01-01

Since 1980, the Lake Tahoe Interagency Monitoring Program (LTIMP) has provided stream-discharge and water quality data—nitrogen (N), phosphorus (P), and suspended sediment—at more than 20 stations in Lake Tahoe Basin streams. To characterize the temporal and spatial patterns in nutrient and sediment loading to the lake, and improve the usefulness of the program and the existing database, we have (1) identified and corrected for sources of bias in the water quality database; (2) generated synthetic datasets for sediments and nutrients, and resampled to compare the accuracy and precision of different load calculation models; (3) using the best models, recalculated total annual loads over the period of record; (4) regressed total loads against total annual and annual maximum daily discharge, and tested for time trends in the residuals; (5) compared loads for different forms of N and P; and (6) tested constituent loads against land use-land cover (LULC) variables using multiple regression. The results show (1) N and P loads are dominated by organic N and particulate P; (2) there are significant long-term downward trends in some constituent loads of some streams; and (3) anthropogenic impervious surface is the most important LULC variable influencing water quality in basin streams. Many of our recommendations for changes in water quality monitoring and load calculation methods have been adopted by the LTIMP.

Response in the water quality of the Salton Sea, California, to changes in phosphorus loading: An empirical modeling approach

USGS Publications Warehouse

Robertson, Dale M.; Schladow, S.G.

2008-01-01

Salton Sea, California, like many other lakes, has become eutrophic because of excessive nutrient loading, primarily phosphorus (P). A Total Maximum Daily Load (TMDL) is being prepared for P to reduce the input of P to the Sea. In order to better understand how P-load reductions should affect the average annual water quality of this terminal saline lake, three different eutrophication programs (BATHTUB, WiLMS, and the Seepage Lake Model) were applied. After verifying that specific empirical models within these programs were applicable to this saline lake, each model was calibrated using water-quality and nutrient-loading data for 1999 and then used to simulate the effects of specific P-load reductions. Model simulations indicate that a 50% decrease in external P loading would decrease near-surface total phosphorus concentrations (TP) by 25-50%. Application of other empirical models demonstrated that this decrease in loading should decrease near-surface chlorophyll a concentrations (Chl a) by 17-63% and increase Secchi depths (SD) by 38-97%. The wide range in estimated responses in Chl a and SD were primarily caused by uncertainty in how non-algal turbidity would respond to P-load reductions. If only the models most applicable to the Salton Sea are considered, a 70-90% P-load reduction is required for the Sea to be classified as moderately eutrophic (trophic state index of 55). These models simulate steady-state conditions in the Sea; therefore, it is difficult to ascertain how long it would take for the simulated changes to occur after load reductions. ?? 2008 Springer Science+Business Media B.V.

A benefit-cost analysis of ten tree species in Modesto, California, U.S.A

Treesearch

E.G. McPherson

2003-01-01

Tree work records for ten species were analyzed to estimate average annual management costs by dbh class for six activity areas. Average annual benefits were calculated by dbh class for each species with computer modeling. Average annual net benefits per tree were greatest for London plane (Platanus acerifolia) ($178.57), hackberry (...

Solar-energy-system performance evaluation, October 1980-August 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wetzel, P.E.

The solar site is an Animal Quarantine Center in Upton, New York, using 2484 ft/sup 2/ of flat-plate collectors and 5300 gallons of solar hot water storage located outside and above ground. The system was designed to provide 20% of the annual heating load and 100% of the annual domestic hot water load. The solar system actually provided 5% of the total system load. Many control and mechanical malfunctions contributed to the poor performance. (MHR)

Estimation of nonpoint-source loads of total nitrogen, total phosphorous, and total suspended solids in the Black, Belle, and Pine River basins, Michigan, by use of the PLOAD model

USGS Publications Warehouse

Syed, Atiq U.; Jodoin, Richard S.

2006-01-01

The Lake St. Clair Regional Monitoring Project partners planned a 3-year assessment study of the surface water in the Lake St. Clair drainage basins in Michigan. This study included water-quality monitoring and analysis, collection of discrete (grab) and automatic water-quality samples, monitoring of bacteria, and the creation of a database to store all relevant data collected from past and future field-data-collection programs. In cooperation with the Lake St. Clair Monitoring Project, the U.S. Geological Survey assessed nonpoint-source loads of nutrients and total suspended solids in the Black, Belle, and Pine River basins. The principal tool for the assessment study was the USEPA’s PLOAD model, a simplified GIS-based numerical program that generates gross estimates of pollutant loads. In this study, annual loads were computed for each watershed using the USEPA’s Simple Method, which is based on scientific studies showing a correlation between different land-use types and loading rates. The two land-use data sets used in the study (representing 1992 and 2001) show a maximum of 0.02-percent change in any of the 15 land use categories between the two timeframes. This small change in land use is reflected in the PLOAD results of the study area between the two time periods. PLOAD model results for the 2001 land-use data include total-nitrogen loads from the Black, Belle, and Pine River basins of approximately 495,599 lb/yr, 156,561 lb/yr, and 121,212 lb/yr, respectively; total-phosphorus loads of 80,777 lb/yr, 25,493 lb/yr, and 19,655 lb/yr, respectively; and total-suspended-solids loads of 5,613,282 lb/yr, 1,831,045 lb/yr, and 1,480,352 lb/yr, respectively. The subbasins in the Black, Belle, and Pine River basin with comparatively high loads are characterized by comparatively high percentages of industrial, commercial, transportation, or residential land use. The results from the PLOAD model provide useful information about the approximate average annual loading rates from the three study basins. In particular, the results identify subbasins with comparatively high loading rates per square mile. This could aid water-resources managers and planners in evaluation of the effectiveness of public expenditures for water-quality improvements, assessment of progress towards achieving established water-quality goals, and planning of preventive actions.

Future export of particulate and dissolved organic carbon from land to coastal zones of the Baltic Sea

NASA Astrophysics Data System (ADS)

Strååt, Kim Dahlgren; Mörth, Carl-Magnus; Undeman, Emma

2018-01-01

The Baltic Sea is a semi-enclosed brackish sea in Northern Europe with a drainage basin four times larger than the sea itself. Riverine organic carbon (Particulate Organic Carbon, POC and Dissolved Organic Carbon, DOC) dominates carbon input to the Baltic Sea and influences both land-to-sea transport of nutrients and contaminants, and hence the functioning of the coastal ecosystem. The potential impact of future climate change on loads of POC and DOC in the Baltic Sea drainage basin (BSDB) was assessed using a hydrological-biogeochemical model (CSIM). The changes in annual and seasonal concentrations and loads of both POC and DOC by the end of this century were predicted using three climate change scenarios and compared to the current state. In all scenarios, overall increasing DOC loads, but unchanged POC loads, were projected in the north. In the southern part of the BSDB, predicted DOC loads were not significantly changing over time, although POC loads decreased in all scenarios. The magnitude and significance of the trends varied with scenario but the sign (+ or -) of the projected trends for the entire simulation period never conflicted. Results were discussed in detail for the "middle" CO2 emission scenario (business as usual, a1b). On an annual and entire drainage basin scale, the total POC load was projected to decrease by ca 7% under this scenario, mainly due to reduced riverine primary production in the southern parts of the BSDB. The average total DOC load was not predicted to change significantly between years 2010 and 2100 due to counteracting decreasing and increasing trends of DOC loads to the six major sub-basins in the Baltic Sea. However, predicted seasonal total loads of POC and DOC increased significantly by ca 46% and 30% in winter and decreased by 8% and 21% in summer over time, respectively. For POC the change in winter loads was a consequence of increasing soil erosion and a shift in duration of snowfall and onset of the spring flood impacting the input of terrestrial litter, while reduced primary production mainly explained the differences predicted in summer. The simulations also showed that future changes in POC and DOC export can vary significantly across the different sub-basins of the Baltic Sea. These changes in organic carbon input may impact future coastal food web structures e.g. by influencing bacterial and phytoplankton production in coastal zones, which in turn may have consequences at higher trophic levels.

7 CFR Appendix A to Subpart B of... - Review Rating Summary, RUS Form 300

Code of Federal Regulations, 2012 CFR

2012-01-01

...—ENGINEERING 11. System Load Conditions and Losses a. Annual System Loses, ____%—Rating:____ b. Annual Load..., RUS Form 300 Borrower Designation ____ Date Prepared ____ Ratings on form are: 0: Unsatisfactory—no... recommendations 3: Satisfactory—no additional action required at this time N/A: Not applicable PART I—TRANSMISSION...

7 CFR Appendix A to Subpart B of... - Review Rating Summary, RUS Form 300

Code of Federal Regulations, 2013 CFR

2013-01-01

...—ENGINEERING 11. System Load Conditions and Losses a. Annual System Loses, ____%—Rating:____ b. Annual Load..., RUS Form 300 Borrower Designation ____ Date Prepared ____ Ratings on form are: 0: Unsatisfactory—no... recommendations 3: Satisfactory—no additional action required at this time N/A: Not applicable PART I—TRANSMISSION...

7 CFR Appendix A to Subpart B of... - Review Rating Summary, RUS Form 300

Code of Federal Regulations, 2010 CFR

2010-01-01

...—ENGINEERING 11. System Load Conditions and Losses a. Annual System Loses, ____%—Rating:____ b. Annual Load..., RUS Form 300 Borrower Designation ____ Date Prepared ____ Ratings on form are: 0: Unsatisfactory—no... recommendations 3: Satisfactory—no additional action required at this time N/A: Not applicable PART I—TRANSMISSION...

7 CFR Appendix A to Subpart B of... - Review Rating Summary, RUS Form 300

Code of Federal Regulations, 2011 CFR

2011-01-01

...—ENGINEERING 11. System Load Conditions and Losses a. Annual System Loses, ____%—Rating:____ b. Annual Load..., RUS Form 300 Borrower Designation ____ Date Prepared ____ Ratings on form are: 0: Unsatisfactory—no... recommendations 3: Satisfactory—no additional action required at this time N/A: Not applicable PART I—TRANSMISSION...

Concentrations, loads, and yields of nutrients and suspended sediment in the South Pacolet, North Pacolet, and Pacolet Rivers, northern South Carolina and southwestern North Carolina, October 2005 to September 2009

USGS Publications Warehouse

Journey, Celeste A.; Caldwell, Andral W.; Feaster, Toby D.; Petkewich, Mattew D.; Bradley, Paul M.

2011-01-01

The U.S. Geological Survey, in cooperation with Spartanburg Water, evaluated the concentrations, loads, and yields of suspended sediment, dissolved ammonia, dissolved nitrate plus nitrite, total organic nitrogen, total nitrogen, dissolved orthophosphate, dissolved phosphorus, and total phosphorus at sites in the South Pacolet, North Pacolet, and Pacolet Rivers in northern South Carolina and southwestern North Carolina from October 1, 2005, to September 30, 2009 (water years 2006 to 2009). Nutrient and sediment loads and yields also were computed for the intervening subbasin of the Pacolet River not represented by the South and North Pacolet River Basins. Except for a few outliers, the majority of the measurements of total nitrogen concentrations were well below the U.S. Environmental Protection Agency recommended guideline of 0.69 milligram per liter for streams and rivers in the nutrient ecoregion IX, which includes the study area within the Pacolet River Basin. Dissolved orthophosphate, dissolved phosphorus, and total phosphorus concentrations were significantly lower at the South Pacolet River site compared to the North Pacolet and Pacolet River sites. About 90 percent of the total phosphorus concentrations at the South Pacolet River site were below the U.S. Environmental Protection Agency recommended guideline of 0.37 milligram per liter, and more than 75 percent of the total phosphorus concentrations at the North Pacolet and Pacolet River sites were above that guideline. At all sites, minimum annual nutrient loads for the estimation period were observed during water year 2008 when severe drought conditions were present. An estimated mean annual total nitrogen load of 37,770 kilograms per year and yield of 2.63 kilograms per hectare per year were determined for the South Pacolet River site for the estimation period. The North Pacolet River site had a mean annual total nitrogen load of 65,890 kilograms per year and yield of 2.19 kilograms per hectare per year. The Pacolet River had a mean annual total nitrogen load of 99,780 kilograms per year and yield of 1.82 kilograms per hectare per year. Mean annual total phosphorus loads of 2,576; 9,404; and 11,710 kilograms per year and yields of 0.180, 0.313, and 0.213 kilograms per hectare per year were estimated at the South Pacolet, North Pacolet, and Pacolet River sites, respectively. Annually, the intervening subbasin of the Pacolet River contributed negligible amounts of total nitrogen and total phosphorus loads, and large losses of dissolved nitrate plus nitrite and orthophosphate loads were determined for the subbasin. Biological (algal) uptake in the two reservoirs in this intervening area was considered the likely explanation for the loss of these constituents. Estimated mean annual suspended-sediment loads were 21,190,000; 9,895,000; and 6,547,000 kilograms per year at the South Pacolet, North Pacolet, and Pacolet River sites, respectively. In the intervening Pacolet River subbasin, computed annual suspended-sediment loads were consistently negative, indicating large percentage losses in annual suspended-sediment load. Sedimentation processes in the two reservoirs are the most likely explanations for these apparent losses. At all sites, the winter season tended to have the highest estimated seasonal dissolved orthophosphate and dissolved nitrate plus nitrite fluxes, and the summer and fall seasons tended to have the lowest fluxes. The reverse pattern, however, was observed in the intervening drainage area in the Pacolet River where the lowest fluxes of dissolved orthophosphate and nitrate plus nitrite occurred during the winter and spring seasons and the highest occurred during the summer and fall seasons. Synoptic samples were collected during a high-flow event in August 2009 at eight sites that represented shoreline and minor tributary drainages. The South Pacolet River site was identified as contributing greater than 80 percent of the cumulative nutrient and sediment l

Sediment loads in the Red River of the North and selected tributaries near Fargo, North Dakota, 2010--2011

USGS Publications Warehouse

Galloway, Joel M.; Nustad, Rochelle A.

2012-01-01

Natural-resource agencies are concerned about possible geomorphic effects of a proposed diversion project to reduce the flood risk in the Fargo-Moorhead metropolitan area. The U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers collected data in the spring of 2010 and 2011, and from June to November 2011, during rainfall-runoff events and base-flow conditions to provide information on sediment transport. The data were used to examine sediment concentrations, loads, and particle-size distributions at nine selected sites in the Red River and its tributaries near the Fargo-Moorhead metropolitan area. Suspended-sediment concentration varied among sites in 2010 and 2011. The least suspended-sediment concentrations were measured at the Red River (site 1) and the Buffalo River (site 9), and the greatest concentrations were measured at the two Sheyenne River sites (sites 3 and 4). Estimated daily suspended-sediment loads were highly variable in 2010 and 2011 in the Red River and its tributaries, with the greatest loads occurring in the spring and the smallest loads occurring in the winter. For the Red River, daily suspended-sediment loads ranged from 26 to 3,500 tons per day at site 1 and from 30 to 9,010 tons per day at site 2. For the Sheyenne River, daily loads ranged from less than 10 to 10,200 tons per day at site 3 and from less than 10 to 4,530 tons per day at site 4. The mean daily load was 191 tons per day in 2010 and 377 tons per day in 2011 for the Maple River, and 610 tons per day in 2011 for the Wild Rice River (annual loads were not computed for 2010). For the three sites that were only sampled in 2011 (sites 7, 8 and 9), the mean daily suspended-sediment loads ranged from 40 tons per day at the Lower Branch Rush River (site 8) to 118 tons per day at the Buffalo River (site 9). For sites that had estimated loads in 2010 and 2011 (sites 1–5), estimated annual (March–November) suspended-sediment loads were greater in 2011 compared to 2010. In 2010, annual loads ranged from 68,650 tons per year at the Maple River (site 5) to 249,040 tons per year at the Sheyenne River (site 3). In 2011, when all nine sites were sampled, annual loads ranged from 8,716 tons per year at the Lower Branch Rush River (site 8) to 552,832 tons per year at the Sheyenne River (site 3). With the exception of the Sheyenne River (site 4), the greatest monthly loads occurred in March for 2010, with as little as 27 percent (site 1) and as much as 42 percent (site 3) of the annual load occurring in March. For 2011, the greatest monthly loads occurred in April, ranging from 33 percent (site 1) to 63 percent (site 7) of the 2011 annual load. A relatively small amount of sediment was transported past the nine sites as bedload in 2010 and 2011. For most of the samples collected at the nine sites, the bedload composed less than 1 percent of the calculated daily total sediment load.

Dissolved-solids transport in surface water of the Muddy Creek Basin, Utah

USGS Publications Warehouse

Gerner, Steven J.

2008-01-01

Muddy Creek is located in the southeastern part of central Utah and is a tributary of the Dirty Devil River, which, in turn, is a tributary of the Colorado River. Dissolved solids transported from the Muddy Creek Basin may be stored in the lower Dirty Devil River Basin, but are eventually discharged to the Colorado River and impact downstream water users. This study used selected dissolved-solids measurements made by various local, State, and Federal agencies from the 1970s through 2006, and additional dissolved-solids data that were collected by the U.S. Geological Survey during April 2004 through November 2006, to compute dissolved-solids loads, determine the distribution of dissolved-solids concentrations, and identify trends in dissolved-solids concentration in surface water of the Muddy Creek Basin. The dissolved-solids concentration values measured in water samples collected from Muddy Creek during April 2004 through October 2006 ranged from 385 milligrams per liter (mg/L) to 5,950 mg/L. The highest dissolved-solids concentration values measured in the study area were in water samples collected at sites in South Salt Wash (27,000 mg/L) and Salt Wash (4,940 to 6,780 mg/L). The mean annual dissolved-solids load in Muddy Creek for the periods October 1976 to September 1980 and October 2005 to September 2006 was smallest at a site near the headwaters (9,670 tons per year [tons/yr]) and largest at a site at the mouth (68,700 tons/yr). For this period, the mean annual yield of dissolved solids from the Muddy Creek Basin was 44 tons per square mile. During October 2005 to September 2006, direct runoff transported as much as 45 percent of the annual dissolved-solids load at the mouth of Muddy Creek. A storm that occurred during October 5?7, 2006 resulted in a peak streamflow at the mouth of Muddy Creek of 7,150 cubic feet per second (ft3/s) and the transport of an estimated 35,000 tons of dissolved solids, which is about 51 percent of the average annual dissolved-solids load at the mouth of Muddy Creek. A significant downward trend in dissolved-solids concentrations from 1973 to 2006 was determined for Muddy Creek at a site just downstream of that portion of the basin containing agricultural land. Dissolved-solids concentrations decreased about 2.1 percent per year; however, the rate of change was a decrease of 1.8 percent per year when dissolved-solids concentrations were adjusted for flow.

40 CFR Table Jj-1 to Subpart Jj of... - Animal Population Threshold Level Below Which Facilities Are Not Required To Report Emissions...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Emissions Under Subpart JJ 1 2 Animal group Average annual animal population (Head) 3 Beef 29,300 Dairy 3... groups except dairy, the average annual animal population represents the total number of animals present at the facility. For dairy facilities, the average annual animal population represents the number of...

40 CFR Table Jj-1 to Subpart Jj of... - Animal Population Threshold Level Below Which Facilities Are Not Required To Report Emissions...

Code of Federal Regulations, 2013 CFR

2013-07-01

... Emissions Under Subpart JJ 1,2 Animal group Average annual animal population (Head) 3 Beef 29,300 Dairy 3... groups except dairy, the average annual animal population represents the total number of animals present at the facility. For dairy facilities, the average annual animal population represents the number of...

50 CFR 218.112 - Permissible methods of taking.

Code of Federal Regulations, 2012 CFR

2012-10-01

... average of 119274 annually). (ii) Pinnipeds: (A) Northern elephant seal (Mirounga angustirostris)—1890 (an...) Short-beaked common dolphin—10 (an average of 2 annually); (vii) Northern elephant seal—10 (an average...

50 CFR 218.112 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

... average of 119274 annually). (ii) Pinnipeds: (A) Northern elephant seal (Mirounga angustirostris)—1890 (an...) Short-beaked common dolphin—10 (an average of 2 annually); (vii) Northern elephant seal—10 (an average...

50 CFR 218.112 - Permissible methods of taking.

Code of Federal Regulations, 2014 CFR

2014-10-01

... average of 119274 annually). (ii) Pinnipeds: (A) Northern elephant seal (Mirounga angustirostris)—1890 (an...) Short-beaked common dolphin—10 (an average of 2 annually); (vii) Northern elephant seal—10 (an average...

Nitrogen concentrations and loads for the Connecticut River at Middle Haddam, Connecticut, computed with the use of autosampling and continuous measurements of water quality for water years 2009 to 2014

USGS Publications Warehouse

Mullaney, John R.; Martin, Joseph W.; Morrison, Jonathan

2018-03-20

The daily and annual loads of nitrate plus nitrite and total nitrogen for the Connecticut River at Middle Haddam, Connecticut, were determined for water years 2009 to 2014. The analysis was done with a combination of methods, which included a predefined rating curve method for nitrate plus nitrite and total nitrogen for water years 2009 to 2011 and a custom rating curve method that included sensor measurements of nitrate plus nitrite nitrogen concentration and turbidity along with mean daily flow to determine total nitrogen loads for water years 2011 to 2014. Instantaneous concentrations of total nitrogen were estimated through the use of a regression model based on sensor measurements at 15-minute intervals of nitrate plus nitrite nitrogen and turbidity for water years 2011 to 2014.Annual total nitrogen loads at the Connecticut River at Middle Haddam ranged from 12,900 to 19,200 metric tons, of which about 42 to 49 percent was in the form of nitrate plus nitrite. The mean 95-percent prediction intervals on daily total nitrogen load estimates were smaller from the custom model, which used sensor data, than those calculated by the predefined model.Annual total nitrogen load estimates at the Connecticut River at Middle Haddam were compared with the upstream load estimates at the Connecticut River at Thompsonville, Conn. Annual gains in total nitrogen loads between the two stations ranged from 3,430 to 6,660 metric tons. These increases between the two stations were attributed to the effects of increased urbanization and to combined annual discharges of 1,540 to 2,090 metric tons of nitrogen from 24 wastewater treatment facilities in the drainage area between the two stations. The contribution of total nitrogen from wastewater discharge between the two stations had declined substantially before the beginning of this study and accounted for from 31 to 52 percent of the gain in nitrogen load between the Thompsonville and Middle Haddam sites.

Assessment of second- and third-order ionospheric effects on regional networks: case study in China with longer CMONOC GPS coordinate time series

NASA Astrophysics Data System (ADS)

Deng, Liansheng; Jiang, Weiping; Li, Zhao; Chen, Hua; Wang, Kaihua; Ma, Yifang

2017-02-01

Higher-order ionospheric (HOI) delays are one of the principal technique-specific error sources in precise global positioning system analysis and have been proposed to become a standard part of precise GPS data processing. In this research, we apply HOI delay corrections to the Crustal Movement Observation Network of China's (CMONOC) data processing (from January 2000 to December 2013) and furnish quantitative results for the effects of HOI on CMONOC coordinate time series. The results for both a regional reference frame and global reference frame are analyzed and compared to clarify the HOI effects on the CMONOC network. We find that HOI corrections can effectively reduce the semi-annual signals in the northern and vertical components. For sites with lower semi-annual amplitudes, the average decrease in magnitude can reach 30 and 10 % for the northern and vertical components, respectively. The noise amplitudes with HOI corrections and those without HOI corrections are not significantly different. Generally, the HOI effects on CMONOC networks in a global reference frame are less obvious than the results in the regional reference frame, probably because the HOI-induced errors are smaller in comparison to the higher noise levels seen when using a global reference frame. Furthermore, we investigate the combined contributions of environmental loading and HOI effects on the CMONOC stations. The largest loading effects on the vertical displacement are found in the mid- to high-latitude areas. The weighted root mean square differences between the corrected and original weekly GPS height time series of the loading model indicate that the mass loading adequately reduced the scatter on the CMONOC height time series, whereas the results in the global reference frame showed better agreements between the GPS coordinate time series and the environmental loading. When combining the effects of environmental loading and HOI corrections, the results with the HOI corrections reduced the scatter on the observed GPS height coordinates better than the height when estimated without HOI corrections, and the combined solutions in the regional reference frame indicate more preferred improvements. Therefore, regional reference frames are recommended to investigate the HOI effects on regional networks.

Nutrient loadings to streams of the continental United States from municipal and industrial effluent?

USGS Publications Warehouse

Maupin, Molly A.; Ivahnenko, Tamara

2011-01-01

Data from the United States Environmental Protection Agency Permit Compliance System national database were used to calculate annual total nitrogen (TN) and total phosphorus (TP) loads to surface waters from municipal and industrial facilities in six major regions of the United States for 1992, 1997, and 2002. Concentration and effluent flow data were examined for approximately 118,250 facilities in 45 states and the District of Columbia. Inconsistent and incomplete discharge locations, effluent flows, and effluent nutrient concentrations limited the use of these data for calculating nutrient loads. More concentrations were reported for major facilities, those discharging more than 1 million gallons per day, than for minor facilities, and more concentrations were reported for TP than for TN. Analytical methods to check and improve the quality of the Permit Compliance System data were used. Annual loads were calculated using "typical pollutant concentrations" to supplement missing concentrations based on the type and size of facilities. Annual nutrient loads for over 26,600 facilities were calculated for at least one of the three years. Sewage systems represented 74% of all TN loads and 58% of all TP loads. This work represents an initial set of data to develop a comprehensive and consistent national database of point-source nutrient loads. These loads can be used to inform a wide range of water-quality management, watershed modeling, and research efforts at multiple scales.

Hydrologic conditions and water quality in an agricultural area in Kleberg and Nueces Counties, Texas, 1996-98

USGS Publications Warehouse

Ockerman, Darwin J.; Petri, Brian L.

2001-01-01

During 1996?98, rainfall and runoff were monitored on a 49,680-acre agricultural watershed in Kleberg and Nueces Counties in South Texas. Nineteen rainfall samples were analyzed for selected nutrients, and runoff samples from 29 storms were analyzed for major ions, nutrients, and pesticides. Loads of nutrients in rainfall and loads of nutrients and pesticides in runoff were computed. For a 40,540-acre part of the watershed (lower study area), constituent loads entering the watershed in rainfall, in runoff from the upper study area, and from agricultural chemical applications to the lower study area were compared with runoff loads exiting the lower study area. Total rainfall for 1996?98 averaged 25.86 inches per year, which is less than the long-term annual average rainfall of 29.80 inches for the area. Rainfall and runoff during 1996?98 were typical of historical patterns, with periods of below average rainfall and runoff interspersed with extreme events. Five individual storms accounted for about 38 percent of the total rainfall and 94 percent of the total runoff. During the 3-year study, the total nitrogen runoff yield from the lower study area was 1.3 pounds per acre per year, compared with 49 pounds per acre per year applied as fertilizer and 3.1 pounds per acre per year from rainfall. While almost all of the fertilizer and rainfall nitrogen was ammonia and nitrate, most of the nitrogen in runoff was particulate organic nitrogen, associated with crop residue. Total nitrogen exiting the lower study area in surface-water runoff was about 2.5 percent of the nitrogen inputs (fertilizer and rainfall nitrogen). Annual deposition of total nitrogen entering the lower study area in rainfall exceeded net yields of total nitrogen exiting the watershed in runoff because most of the rainfall does not contribute to runoff. During the study, the total phosphorus runoff yield from the lower study area was 0.48 pound per acre per year compared with 4.2 pounds per acre per year applied as fertilizer and 0.03 pound per acre per year from rainfall. Twenty-one pesticides were detected in runoff with varying degrees of frequency during the study. The herbicide atrazine was detected in all runoff samples. All of the most frequently detected pesticides (atrazine, trifluralin, simazine, pendimethalin, and diuron) exhibited higher concentrations during the pre-harvest period (March? May) than during the post-harvest period (August? October). During 1996?98, an average of 0.37 pound per acre per year of atrazine was applied to the lower study area. During the same period, 0.0027 pound per acre per year of atrazine and its breakdown product deethylatrazine exited the lower study area in runoff (about 0.7 percent of the total atrazine applied to the cropland). During 1997, when heavy rainfall occurred during the months of April and May, the atrazine plus deethylatrazine exiting the lower study area was 1.8 percent of the applied atrazine. The 1996?98 average sediment yield was 610 pounds per acre per year. Sediment loads from the study area are associated with large storm events. Of the 45,300 tons of sediment transported from the study area during 1996?98 about 87 percent was transported during the three largest runoff events (April 1997, October 1997, and October 1998). Runoff-weighted average concentrations were computed for selected nutrients and pesticides. The 1996?98 runoff-weighted concentrations for total nitrogen and total phosphorus were 1.3 and 0.50 milligrams per liter, respectively. The 1996?98 runoff-weighted concentration for atrazine plus deethylatrazine was 2.7 micrograms per liter.

A comparison of annual vertical crustal displacements from GPS and Gravity Recovery and Climate Experiment (GRACE) over Europe

NASA Astrophysics Data System (ADS)

van Dam, T.; Wahr, J.; LavalléE, David

2007-03-01

We compare approximately 3 years of GPS height residuals (with respect to the International Terrestrial Reference Frame) with predictions of vertical surface displacements derived from the Gravity Recovery and Climate Experiment (GRACE) gravity fields for stations in Europe. An annual signal fit to the residual monthly heights, corrected for atmospheric pressure and barotropic ocean loading effects, should primarily represent surface displacements due to long-wavelength variations in water storage. A comparison of the annual height signal from GPS and GRACE over Europe indicates that at most sites, the annual signals do not agree in amplitude or phase. We find that unlike the annual signal predicted from GRACE, the annual signal in the GPS heights is not coherent over the region, displaying significant variability from site to site. Confidence in the GRACE data and the unlikely possibility of large-amplitude small-scale features in the load field not captured by the GRACE data leads us to conclude that some of the discrepancy between the GPS and GRACE observations is due to technique errors in the GPS data processing. This is evidenced by the fact that the disagreement between GPS and GRACE is largest at coastal sites, where mismodeling of the semidiurnal ocean tidal loading signal can result in spurious annual signals.

Earth radiation budget measurements from satellites and their interpretation for climate modeling and studies

NASA Technical Reports Server (NTRS)

Vonderhaar, T. H.; Stephens, G. L.; Campbell, G. G.

1980-01-01

The annual and seasonal averaged Earth atmosphere radiation budgets derived from the most complete set of satellite observations available are presented. The budgets were derived from a composite of 48 monthly mean radiation budget maps. Annually and seasonally averaged radiation budgets are presented as global averages and zonal averages. The geographic distribution of the various radiation budget quantities is described. The annual cycle of the radiation budget was analyzed and the annual variability of net flux was shown to be largely dominated by the regular semi and annual cycles forced by external Earth-Sun geometry variations. Radiative transfer calculations were compared to the observed budget quantities and surface budgets were additionally computed with particular emphasis on discrepancies that exist between the present computations and previous surface budget estimates.

Water and nonpoint source pollution estimation in the watershed with limited data availability based on hydrological simulation and regression model.

PubMed

Huiliang, Wang; Zening, Wu; Caihong, Hu; Xinzhong, Du

2015-09-01

Nonpoint source (NPS) pollution is considered as the main reason for water quality deterioration; thus, to quantify the NPS loads reliably is the key to implement watershed management practices. In this study, water quality and NPS loads from a watershed with limited data availability were studied in a mountainous area in China. Instantaneous water discharge was measured through the velocity-area method, and samples were taken for water quality analysis in both flood and nonflood days in 2010. The streamflow simulated by Hydrological Simulation Program-Fortran (HSPF) from 1995 to 2013 and a regression model were used to estimate total annual loads of various water quality parameters. The concentrations of total phosphorus (TP) and total nitrogen (TN) were much higher during the flood seasons, but the concentrations of ammonia nitrogen (NH3-N) and nitrate nitrogen (NO3-N) were lower during the flood seasons. Nevertheless, only TP concentration was positively correlated with the flow rate. The fluctuation of annual load from this watershed was significant. Statistical results indicated the significant contribution of pollutant fluxes during flood seasons to annual fluxes. The loads of TP, TN, NH3-N, and NO3-N in the flood seasons were accounted for 58-85, 60-82, 63-88, 64-81% of the total annual loads, respectively. This study presented a new method for estimation of the water and NPS loads in the watershed with limited data availability, which simplified data collection to watershed model and overcame the scale problem of field experiment method.

40 CFR 61.356 - Recordkeeping requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., annual average flow-weighted benzene concentration, and annual benzene quantity. (2) For each waste... measurements, calculations, and other documentation used to determine that the continuous flow of process... benzene concentrations in the waste, the annual average flow-weighted benzene concentration of the waste...

40 CFR 61.356 - Recordkeeping requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., annual average flow-weighted benzene concentration, and annual benzene quantity. (2) For each waste... measurements, calculations, and other documentation used to determine that the continuous flow of process... benzene concentrations in the waste, the annual average flow-weighted benzene concentration of the waste...

40 CFR 61.356 - Recordkeeping requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., annual average flow-weighted benzene concentration, and annual benzene quantity. (2) For each waste... measurements, calculations, and other documentation used to determine that the continuous flow of process... benzene concentrations in the waste, the annual average flow-weighted benzene concentration of the waste...

Atmospheric deposition as an important nitrogen load to a typical agro-ecosystem in the Huang-Huai-Hai Plain. 2. Seasonal and inter-annual variations and their implications (2008-2012)

NASA Astrophysics Data System (ADS)

Huang, Ping; Zhang, Jiabao; Ma, Donghao; Wen, Zhaofei; Wu, Shengjun; Garland, Gina; Pereira, Engil Isadora Pujol; Zhu, Anning; Xin, Xiuli; Zhang, Congzhi

2016-03-01

Atmospheric nitrogen (N) deposition, an important N source to agro-ecosystems, has increased intensively in China during recent decades. However, knowledge on temporal variations of total N deposition and their influencing factors is limited due to lack of systematic monitoring data. In this study, total N deposition, including dry and wet components, was monitored using the water surrogate surface method for a typical agro-ecosystem with a winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.) rotation system in the Huang-Huai-Hai Plain from May 2008 to April 2012. The results indicated that annual total N deposition ranged from 23.8 kg N ha-1 (2009-2010) to 40.3 kg N ha-1 (2008-2009) and averaged 31.8 kg N ha-1. Great inter-annual variations were observed during the sampling period, due to differences in annual rainfall and gaseous N losses from farmlands. Monthly total N deposition varied greatly, from less than 0.6 kg N ha-1 (January, 2010) to over 8.0 kg N ha-1 (August, 2008), with a mean value of 2.6 kg N ha-1. In contrast to wet deposition, dry portions generally contributed more to the total, except in the precipitation-intensive months, accounting for 65% in average. NH4+ -N was the dominant species in N deposition and its contribution to total deposition varied from 6% (December, 2009) to 79% (July, 2008), averaging 53%. The role of organic N (O-N) in both dry and wet deposition was equal to or even greater than that of NO3- -N. Influencing factors such as precipitation and its seasonal distribution, reactive N sources, vegetation status, field management practices, and weather conditions were responsible for the temporal variations of atmospheric N deposition and its components. These results are helpful for reducing the knowledge gaps in the temporal variations of atmospheric N deposition and their influencing factors in different ecosystems, to improve the understandings on N budget in the typical agro-ecosystem, and to provide references and recommendations for field nutrient management in this region.

Traits of surface water pollution under climate and land use changes: A remote sensing and hydrological modeling approach

NASA Astrophysics Data System (ADS)

Jordan, Yuyan C.; Ghulam, Abduwasit; Hartling, Sean

2014-01-01

In this paper, spatial and temporal trajectories of land cover/land use change (LCLUC) derived from Landsat data record are combined with hydrological modeling to explore the implication of vegetation dynamics on soil erosion and total suspended sediment (TSS) loading to surface rivers. The inter-annual coefficient of variation (CoV) of normalized difference vegetation index (NDVI) is used to screen the LCLUC and climate change. The Soil and Water Assessment Tool (SWAT) is employed to identify the monthly TSS for two times interval (1991 to 2001 and 2001 to 2011) at subbasin levels. SWAT model is calibrated from 1991 to 2001 and validated from 2002 to 2011 at three USGS gauging sites located in the study area. The Spearman's rank correlation of annual mean TSS is used to assess the temporal trends of TSS dynamics in the subbasins in the two study periods. The spatial correlation among NDVI, LCLUC, climate change and TSS loading rate changes is quantified by using linear regression model and negative/positive trend analysis. Our results showed that higher rainfall yields contribute to higher TSS loading into surface waters. A higher inter-annual accumulated vegetation index and lower inter-annual CoV distributed over the uplands resulted in a lower TSS loading rate, while a relatively low vegetation index with larger CoV observed over lowlands resulted in a higher TSS loading rate. The TSS loading rate at the basin outlet increased with the decrease of annual NDVI due to expanding urban areas in the watershed. The results also suggested nonlinearity between the trends of TSS loading with any of a specific land cover change because of the fact that the contribution of a factor can be influenced by the effects of other factors. However, dominant factors that shape the relationship between the trend of TSS loading and specific land cover changes were detected. The change of forest showed a negative relationship while agriculture and pasture demonstrated positive relationships with TSS loading change. Our results do not show any significant causal relationship between urbanization and the TSS loading change suggesting that further investigation needs to be carried out to understand the mechanism of the impact of urban sprawl on surface water quality.

Influence of sampling frequency and load calculation methods on quantification of annual river nutrient and suspended solids loads.

PubMed

Elwan, Ahmed; Singh, Ranvir; Patterson, Maree; Roygard, Jon; Horne, Dave; Clothier, Brent; Jones, Geoffrey

2018-01-11

Better management of water quality in streams, rivers and lakes requires precise and accurate estimates of different contaminant loads. We assessed four sampling frequencies (2 days, weekly, fortnightly and monthly) and five load calculation methods (global mean (GM), rating curve (RC), ratio estimator (RE), flow-stratified (FS) and flow-weighted (FW)) to quantify loads of nitrate-nitrogen (NO 3 - -N), soluble inorganic nitrogen (SIN), total nitrogen (TN), dissolved reactive phosphorus (DRP), total phosphorus (TP) and total suspended solids (TSS), in the Manawatu River, New Zealand. The estimated annual river loads were compared to the reference 'true' loads, calculated using daily measurements of flow and water quality from May 2010 to April 2011, to quantify bias (i.e. accuracy) and root mean square error 'RMSE' (i.e. accuracy and precision). The GM method resulted into relatively higher RMSE values and a consistent negative bias (i.e. underestimation) in estimates of annual river loads across all sampling frequencies. The RC method resulted in the lowest RMSE for TN, TP and TSS at monthly sampling frequency. Yet, RC highly overestimated the loads for parameters that showed dilution effect such as NO 3 - -N and SIN. The FW and RE methods gave similar results, and there was no essential improvement in using RE over FW. In general, FW and RE performed better than FS in terms of bias, but FS performed slightly better than FW and RE in terms of RMSE for most of the water quality parameters (DRP, TP, TN and TSS) using a monthly sampling frequency. We found no significant decrease in RMSE values for estimates of NO 3 - N, SIN, TN and DRP loads when the sampling frequency was increased from monthly to fortnightly. The bias and RMSE values in estimates of TP and TSS loads (estimated by FW, RE and FS), however, showed a significant decrease in the case of weekly or 2-day sampling. This suggests potential for a higher sampling frequency during flow peaks for more precise and accurate estimates of annual river loads for TP and TSS, in the study river and other similar conditions.

Environmental Effects on Long Term Displacement Data of Woven Fabric Webbings Under Constant Load for Inflatable Structures

NASA Technical Reports Server (NTRS)

Kenner, WInfred S.; Jones, Thomas C.; Doggett, William R.; Duncan, Quinton; Plant, James

2015-01-01

An experimental study of the effects of environmental temperature and humidity conditions on long-term creep displacement data of high strength Kevlar and VectranTM woven fabric webbings under constant load for inflatable structures is presented. The restraint layer of an inflatable structure for long-duration space exploration missions is designed to bear load and consists of an assembly of high strength webbings. Long-term creep displacement data of webbings can be utilized by designers to validate service life parameters of restraint layers of inflatable structures. Five groups of high-strength webbings were researched over a two year period. Each group had a unique webbing length, load rating, applied load, and test period. The five groups consisted of 1.) 6K Vectran webbings loaded to 49% ultimate tensile strength (UTS), 2.) 6K Vectran webbings loaded to 55% UTS, 3.) 12.5K Vectran webbings loaded to 22% UTS, 4.) 6K Kevlar webbings loaded to 40% and 43% UTS, and 5.) 6K Kevlar webbings loaded to 48% UTS. Results show that all webbing groups exhibit the initial two stages of three of a typical creep curve of an elastic material. Results also show that webbings exhibit unique local wave patterns over the duration of the test period. Data indicate that the local pattern is primarily generated by daily variations in relative humidity values within the test facility. Data indicate that after a three to six month period, where webbings reach a steady-state creep condition, an annual sinusoidal displacement pattern is exhibited, primarily due to variations in annual mean temperature values. Data indicates that variations in daily temperature values and annual mean humidity values have limited secondary effects on creep displacement behavior. Results show that webbings in groups 2 and 5 do not exhibit well defined annual displacement patterns because the magnitude of the applied loads cause large deformations, and data indicate that material yielding within a webbing tends to neutralize the annual sinusoidal displacement pattern. Study indicates that applied load, environmental effects, mechanical strength, coefficient of thermal expansion, and hygroscopic properties of webbings are fundamental requirements for quantifying accurate creep displacements and behaviors over multiple year time periods. Results from a study of the environmental effects on long-term creep displacement data of Kevlar and Vectran woven webbings are presented to increase the knowledge base of webbing materials and to enhance designs of inflatable space structures for long-duration space missions.

Long-term trends of phosphorus concentrations in an artificial lake: Socio-economic and climate drivers.

PubMed

Vystavna, Yuliya; Hejzlar, Josef; Kopáček, Jiří

2017-01-01

European freshwater ecosystems have undergone significant human-induced and environmentally-driven variations in nutrient export from catchments throughout the past five decades, mainly in connection with changes in land-use, agricultural practice, waste water production and treatment, and climatic conditions. We analysed the relations among concentration of total phosphorus (TP) in the Slapy Reservoir (a middle reservoir of the Vltava River Cascade, Czechia), and socio-economic and climatic factors from 1963 to 2015. The study was based on a time series analysis, using conventional statistical tools, and the identification of breaking points, using a segmented regression. Results indicated clear long-term trends and seasonal patterns of TP, with annual average TP increasing up until 1991 and decreasing from 1992 to 2015. Trends in annual, winter and spring average TP concentrations reflected a shift in development of sewerage and sanitary infrastructure, agricultural application of fertilizers, and livestock production in the early 1990s that was associated with changes from the planned to the market economy. No trends were observed for average TP in autumn. The summer average TP has fluctuated with increased amplitude since 1991 in connection with recent climate warming, changes in thermal stratification stability, increased water flow irregularities, and short-circuiting of TP-rich inflow during high flow events. The climate-change-induced processes confound the generally declining trend in lake-water TP concentration and can result in eutrophication despite decreased phosphorus loads from the catchment. Our findings indicate the need of further reduction of phosphorus sources to meet ecological quality standards of the EU Water Framework Directive because the climate change may lead to a greater susceptibility of the aquatic ecosystem to the supply of nutrients.

Optimisation potential for a SBR plant based upon integrated modelling for dry and wet weather conditions.

PubMed

Rönner-Holm, S G E; Kaufmann Alves, I; Steinmetz, H; Holm, N C

2009-01-01

Integrated dynamic simulation analysis of a full-scale municipal sequential batch reactor (SBR) wastewater treatment plant (WWTP) was performed using the KOSMO pollution load simulation model for the combined sewer system (CSS) and the ASM3 + EAWAG-BioP model for the WWTP. Various optimising strategies for dry and storm weather conditions were developed to raise the purification and hydraulic performance and to reduce operation costs based on simulation studies with the calibrated WWTP model. The implementation of some strategies on the plant led to lower effluent values and an average annual saving of 49,000 euro including sewage tax, which is 22% of the total running costs. Dynamic simulation analysis of CSS for an increased WWTP influent over a period of one year showed high potentials for reducing combined sewer overflow (CSO) volume by 18-27% and CSO loads for COD by 22%, NH(4)-N and P(total) by 33%. In addition, the SBR WWTP could easily handle much higher influents without exceeding the monitoring values. During the integrated simulation of representative storm events, the total emission load for COD dropped to 90%, the sewer system emitted 47% less, whereas the pollution load in the WWTP effluent increased to only 14% with 2% higher running costs.

Dietary Glycemic Load, Glycemic Index, and Carbohydrate Intake on the Risk of Lung Cancer among Men and Women in Shanghai.

PubMed

Sun, Jiang-Wei; Zheng, Wei; Li, Hong-Lan; Gao, Jing; Yang, Gong; Gao, Yu-Tang; Rothman, Nat; Lan, Qing; Shu, Xiao-Ou; Xiang, Yong-Bing

2018-01-01

To investigate the potential influence of dietary glycemic index, glycemic load, or carbohydrate intake and lung cancer risk in Shanghai. We prospectively investigated the associations among 130,858 participants in the Shanghai Women's and Men's Health Studies. Diet was assessed using validated food-frequency questionnaires. Lung cancer cases were ascertained through annual record linkage and every 2-3 years in-home visits. Cox proportional hazard regression model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). After excluding the first 2 years of observation, 1312 participants (including 649 women and 663 men) developed lung cancer during an average follow-up of 14.8 (SD: 2.0) years for SWHS and 9.3 (SD: 1.6) years for SMHS. In multivariable analysis, no statistically significant associations were observed between glycemic index, glycemic load, and carbohydrate intake and lung cancer risk for either men or women. Similar results were observed among never smokers, and participants without history of lung disease, diabetes, or hypertension. Stratification by body mass index or menopause status also did not alter the findings. Our studies, conducted in populations who habitually have high-carbohydrate diets, provide no evidence that dietary glycemic index, glycemic load, or carbohydrate intake is associated with lung cancer risk.

Year-to-year variations in annual average indoor 222Rn concentrations.

PubMed

Martz, D E; Rood, A S; George, J L; Pearson, M D; Langner, G H

1991-09-01

Annual average indoor 222Rn concentrations in 40 residences in and around Grand Junction, CO, have been measured repeatedly since 1984 using commercial alpha-track monitors (ATM) deployed for successive 12-mo time periods. Data obtained provide a quantitative measure of the year-to-year variations in the annual average Rn concentrations in these structures over this 6-y period. A mean coefficient of variation of 25% was observed for the year-to-year variability of the measurements at 25 sampling stations for which complete data were available. Individual coefficients of variation at the various stations ranged from a low of 7.7% to a high of 51%. The observed mean coefficient of variation includes contributions due to the variability in detector response as well as the true year-to-year variation in the annual average Rn concentrations. Factoring out the contributions from the measured variability in the response of the detectors used, the actual year-to-year variability of the annual average Rn concentrations was approximately 22%.

Assessment of annual pollutant loads in combined sewers from continuous turbidity measurements: sensitivity to calibration data.

PubMed

Lacour, C; Joannis, C; Chebbo, G

2009-05-01

This article presents a methodology for assessing annual wet weather Suspended Solids (SS) and Chemical Oxygen Demand (COD) loads in combined sewers, along with the associated uncertainties from continuous turbidity measurements. The proposed method is applied to data from various urban catchments in the cities of Paris and Nantes. The focus here concerns the impact of the number of rain events sampled for calibration (i.e. through establishing linear SS/turbidity or COD/turbidity relationships) on the uncertainty of annual pollutant load assessments. Two calculation methods are investigated, both of which rely on Monte Carlo simulations: random assignment of event-specific calibration relationships to each individual rain event, and the use of an overall relationship built from the entire available data set. Since results indicate a fairly low inter-event variability for calibration relationship parameters, an accurate assessment of pollutant loads can be derived, even when fewer than 10 events are sampled for calibration purposes. For operational applications, these results suggest that turbidity could provide a more precise evaluation of pollutant loads at lower cost than typical sampling methods.

20 CFR 30.811 - How will OWCP calculate the duration and extent of a covered Part E employee's initial period of...

Code of Federal Regulations, 2011 CFR

2011-04-01

... exceed 50 percent of his or her average annual wage, OWCP will pay the employee $15,000 as compensation... did not exceed 75 percent of such average annual wage, OWCP will pay the employee $10,000 as... EEOICPA Determinations of Average Annual Wage and Percentages of Loss § 30.811 How will OWCP calculate the...

20 CFR 30.811 - How will OWCP calculate the duration and extent of a covered Part E employee's initial period of...

Code of Federal Regulations, 2010 CFR

2010-04-01

... exceed 50 percent of his or her average annual wage, OWCP will pay the employee $15,000 as compensation... did not exceed 75 percent of such average annual wage, OWCP will pay the employee $10,000 as... EEOICPA Determinations of Average Annual Wage and Percentages of Loss § 30.811 How will OWCP calculate the...

Wind power as an electrical energy source in Illinois

NASA Astrophysics Data System (ADS)

Wendland, W. M.

1982-03-01

A preliminary estimate of the total wind power available in Illinois was made using available historical data, and projections of cost savings due to the presence of wind-generated electricity were attempted. Wind data at 10 m height were considered from nine different sites in the state, with three years data nominally being included. Wind-speed frequency histograms were developed for day and night periods, using a power law function to extrapolate the 10 m readings to 20 m. Wind speeds over the whole state were found to average over 8 mph, the cut-in point for most wind turbines, for from 40-63% of the time. A maximum of 75% run-time was determined for daylight hours in April-May. A reference 1.8 kW windpowered generator was used in annual demand projections for a reference one family home, using the frequency histograms. The small generator was projected to fulfill from 25-53% of the annual load, and, based on various cost assumptions, exhibited paybacks taking from 14-27 yr.

Response of non-point source pollutant loads to climate change in the Shitoukoumen reservoir catchment.

PubMed

Zhang, Lei; Lu, Wenxi; An, Yonglei; Li, Di; Gong, Lei

2012-01-01

The impacts of climate change on streamflow and non-point source pollutant loads in the Shitoukoumen reservoir catchment are predicted by combining a general circulation model (HadCM3) with the Soil and Water Assessment Tool (SWAT) hydrological model. A statistical downscaling model was used to generate future local scenarios of meteorological variables such as temperature and precipitation. Then, the downscaled meteorological variables were used as input to the SWAT hydrological model calibrated and validated with observations, and the corresponding changes of future streamflow and non-point source pollutant loads in Shitoukoumen reservoir catchment were simulated and analyzed. Results show that daily temperature increases in three future periods (2010-2039, 2040-2069, and 2070-2099) relative to a baseline of 1961-1990, and the rate of increase is 0.63°C per decade. Annual precipitation also shows an apparent increase of 11 mm per decade. The calibration and validation results showed that the SWAT model was able to simulate well the streamflow and non-point source pollutant loads, with a coefficient of determination of 0.7 and a Nash-Sutcliffe efficiency of about 0.7 for both the calibration and validation periods. The future climate change has a significant impact on streamflow and non-point source pollutant loads. The annual streamflow shows a fluctuating upward trend from 2010 to 2099, with an increase rate of 1.1 m(3) s(-1) per decade, and a significant upward trend in summer, with an increase rate of 1.32 m(3) s(-1) per decade. The increase in summer contributes the most to the increase of annual load compared with other seasons. The annual NH (4) (+) -N load into Shitoukoumen reservoir shows a significant downward trend with a decrease rate of 40.6 t per decade. The annual TP load shows an insignificant increasing trend, and its change rate is 3.77 t per decade. The results of this analysis provide a scientific basis for effective support of decision makers and strategies of adaptation to climate change.

Estimation of selenium loads entering the south arm of Great Salt Lake, Utah, from May 2006 through March 2008

USGS Publications Warehouse

Naftz, David L.; Johnson, William P.; Freeman, Michael L.; Beisner, Kimberly; Diaz, Ximena; Cross, VeeAnn A.

2009-01-01

Discharge and water-quality data collected from six streamflow-gaging stations were used in combination with the LOADEST software to provide an estimate of total (dissolved + particulate) selenium (Se) load to the south arm of Great Salt Lake (GSL) from May 2006 through March 2008. Total estimated Se load to GSL during this time period was 2,370 kilograms (kg). The 12-month estimated Se load to GSL for May 1, 2006, to April 30, 2007, was 1,560 kg. During the 23-month monitoring period, inflows from the Kennecott Utah Copper Corporation (KUCC) Drain and Bear River outflow contributed equally to the largest proportion of total Se load to GSL, accounting for 49 percent of the total Se load. Five instantaneous discharge measurements at three sites along the railroad causeway indicate a consistent net loss of Se mass from the south arm to the north arm of GSL (mean = 2.4 kg/day, n = 5). Application of the average daily loss rate equates to annual Se loss rate to the north arm of 880 kg (56 percent of the annual Se input to the south arm). The majority of Se in water entering GSL is in the dissolved (less than 0.45 micron) state and ranges in concentration from 0.06 to 35.7 micrograms per liter (ug/L). Particulate Se concentration ranged from less than 0.05 to 2.5 ug/L. Except for the KUCC Drain streamflow-gaging station, dissolved (less than 0.45 um) inflow samples contain an average of 21 percent selenite (SeO32-) during two sampling events (May 2006 and 2007). Selenium concentration in water samples collected from four monitoring sites within GSL during May 2006 through August 2007 were used to understand how the cumulative Se load was being processed by various biogeochemical processes within the lake. On the basis of the Mann-Kendall test results, changes in dissolved Se concentration at the four monitoring sites indicate a statistically significant (90-percent confidence interval) upward trend in Se concentration over the 16-month monitoring period. Furthermore, the upward trend at three of the four GSL sites also was significant at the 95-percent confidence interval. Given the large amount of Se removal from GSL of greater than 1,900 kg/year by gaseous flux and permanent sedimentation, the observed increase in both dissolved (less than 0.45 micron) and total (dissolved + particulate) Se in the open-water monitoring sites indicates additional, unquantified source(s) of Se are contributing substantial masses of Se load to the south arm of GSL. Potential source(s) of this unmeasured Se load could include (1) Se loads entering GSL from unmeasured surface inflows; (2) ground-water discharge to GSL; (3) wind-blown dust that is deposited directly on the lake surface; (4) wet and dry atmospheric deposition falling directly on the lake surface; and (5) lake sediment pore-water diffusion into the overlying water column. Electrical resistivity surveys in the south part of GSL indicate areas of potential ground-water discharge to the open water of GSL and elevated (exceeding 10,000 ug/L) Se concentrations have been previously measured in ground water within 1.6 kilometers of the south shore of GSL.

Comparison of mercury mass loading in streams to atmospheric deposition in watersheds of Western North America: Evidence for non-atmospheric mercury sources.

PubMed

Domagalski, Joseph; Majewski, Michael S; Alpers, Charles N; Eckley, Chris S; Eagles-Smith, Collin A; Schenk, Liam; Wherry, Susan

2016-10-15

Annual stream loads of mercury (Hg) and inputs of wet and dry atmospheric Hg deposition to the landscape were investigated in watersheds of the Western United States and the Canadian-Alaskan Arctic. Mercury concentration and discharge data from flow gauging stations were used to compute annual mass loads with regression models. Measured wet and modeled dry deposition were compared to annual stream loads to compute ratios of Hg stream load to total Hg atmospheric deposition. Watershed land uses or cover included mining, undeveloped, urbanized, and mixed. Of 27 watersheds that were investigated, 15 had some degree of mining, either of Hg or precious metals (gold or silver), where Hg was used in the amalgamation process. Stream loads in excess of annual Hg atmospheric deposition (ratio>1) were observed in watersheds containing Hg mines and in relatively small and medium-sized watersheds with gold or silver mines, however, larger watersheds containing gold or silver mines, some of which also contain large dams that trap sediment, were sometimes associated with lower load ratios (<0.2). In the non-Arctic regions, watersheds with natural vegetation tended to have low ratios of stream load to Hg deposition (<0.1), whereas urbanized areas had higher ratios (0.34-1.0) because of impervious surfaces. This indicated that, in ecosystems with natural vegetation, Hg is retained in the soil and may be transported subsequently to streams as a result of erosion or in association with dissolved organic carbon. Arctic watersheds (Mackenzie and Yukon Rivers) had a relatively elevated ratio of stream load to atmospheric deposition (0.27 and 0.74), possibly because of melting glaciers or permafrost releasing previously stored Hg to the streams. Overall, our research highlights the important role of watershed characteristics in determining whether a landscape is a net source of Hg or a net sink of atmospheric Hg. Published by Elsevier B.V.

Comparison of mercury mass loading in streams to atmospheric deposition in watersheds of Western North America: Evidence for non-atmospheric mercury sources

USGS Publications Warehouse

Domagalski, Joseph L.; Majewski, Michael S.; Alpers, Charles N.; Eckley, Chris S.; Eagles-Smith, Collin A.; Schenk, Liam N.; Wherry, Susan

2016-01-01

Annual stream loads of mercury (Hg) and inputs of wet and dry atmospheric Hg deposition to the landscape were investigated in watersheds of the Western United States and the Canadian-Alaskan Arctic. Mercury concentration and discharge data from flow gauging stations were used to compute annual mass loads with regression models. Measured wet and modeled dry deposition were compared to annual stream loads to compute ratios of Hg stream load to total Hg atmospheric deposition. Watershed land uses or cover included mining, undeveloped, urbanized, and mixed. Of 27 watersheds that were investigated, 15 had some degree of mining, either of Hg or precious metals (gold or silver), where Hg was used in the amalgamation process. Stream loads in excess of annual Hg atmospheric deposition (ratio > 1) were observed in watersheds containing Hg mines and in relatively small and medium-sized watersheds with gold or silver mines, however, larger watersheds containing gold or silver mines, some of which also contain large dams that trap sediment, were sometimes associated with lower load ratios (< 0.2). In the non-Arctic regions, watersheds with natural vegetation tended to have low ratios of stream load to Hg deposition (< 0.1), whereas urbanized areas had higher ratios (0.34–1.0) because of impervious surfaces. This indicated that, in ecosystems with natural vegetation, Hg is retained in the soil and may be transported subsequently to streams as a result of erosion or in association with dissolved organic carbon. Arctic watersheds (Mackenzie and Yukon Rivers) had a relatively elevated ratio of stream load to atmospheric deposition (0.27 and 0.74), possibly because of melting glaciers or permafrost releasing previously stored Hg to the streams. Overall, our research highlights the important role of watershed characteristics in determining whether a landscape is a net source of Hg or a net sink of atmospheric Hg.

Alternatives to the Moving Average

Treesearch

Paul C. van Deusen

2001-01-01

There are many possible estimators that could be used with annual inventory data. The 5-year moving average has been selected as a default estimator to provide initial results for states having available annual inventory data. User objectives for these estimates are discussed. The characteristics of a moving average are outlined. It is shown that moving average...

Evaluation of nutrient loads from a mountain forest including storm runoff loads.

PubMed

Kunimatsu, T; Otomori, T; Osaka, K; Hamabata, E; Komai, Y

2006-01-01

Water quality and flow rates at a weir installed on the end of Aburahi-S Experimental Watershed (3.34 ha) were measured once a week from 2001 to 2003 and in appropriate intervals from 30 min to 6 h during five storm runoff events caused by each rainfall from 8 mm to 417 mm. The average annual loads of total nitrogen (TN) and total phosphorus (TP) were calculated to be 19.0 and 0.339 kg ha(-1) y(-1) from the periodical data by using the integration interval-loads method (ILM), which did not properly account for storm runoff loads. Three types of L(Q) equations (L = aQ(b)) were derived from correlations between loading rates L and flow rates Q obtained from the periodic observation and from storm runoff observation. L(Q) equation method (LQM), which was derived from the storm runoff observation and allowed for the hysteresis of discharge of materials, gave 9.68 and 0.159 kg ha(-1) y(-1), respectively, by substitution of the sequential hourly data of flow rates. L(R) equation (L = c(R - r)d) was derived from the correlations between the loads and the effective rainfall depth (R - r) measured during the storm runoff events, and L(R) equation method (LRM) calculated 9.83 +/- 1.68 and 0.175 +/- 0.0761 kg ha(-1) y(-1), respectively, by using the rainfall data for the past 16 years. The atmospheric input-fluxes of TN and TP were 16.5 and 0.791 kg ha(-1) y(-1).

Modeling Nutrient Release in the Tai Lake Basin of China: Source Identification and Policy Implications

NASA Astrophysics Data System (ADS)

Liu, Beibei; Liu, Heng; Zhang, Bing; Bi, Jun

2013-03-01

Because nutrient enrichment has become increasingly severe in the Tai Lake Basin of China, identifying sources and loads is crucial for watershed nutrient management. This paper develops an empirical framework to estimate nutrient release from five major sectors, which requires fewer input parameters and produces acceptable accuracy. Sectors included are industrial manufacturing, livestock breeding (industrial and family scale), crop agriculture, household consumption (urban and rural), and atmospheric deposition. Results show that in the basin (only the five sectors above), total nutrient loads of nitrogen (N) and phosphorus (P) into aquatic systems in 2008 were 33043.2 tons N a-1 and 5254.4 tons P a-1, and annual area-specific nutrient loads were 1.94 tons N km-2 and 0.31 tons P km-2. Household consumption was the major sector having the greatest impact (46 % in N load, 47 % in P load), whereas atmospheric deposition (18 %) and crop agriculture (15 %) sectors represented other significant proportions of N load. The load estimates also indicate that 32 % of total P came from the livestock breeding sector, making it the second largest phosphorus contributor. According to the nutrient pollution sectors, six best management practices are selected for cost-effectiveness analysis, and feasible options are recommended. Overall, biogas digester construction on industrial-scale farms is proven the most cost-effective, whereas the building of rural decentralized facilities is the best alternative under extreme financial constraint. However, the reduction potential, average monetary cost, and other factors such as risk tolerance of policy makers should all be considered in the actual decision-making process.

Increasing runoff and sediment load from the Greenland ice sheet at kangerlussuaq (Sonder Stromfjord) in a 30-year perspective, 1979-2008

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mernild, Sebastian Haugard; Liston, Glen; Hasholt, Bent

2009-01-01

This observation and modeling study provides insights into runoff and sediment load exiting the Watson River drainage basin, Kangerlussuaq, West Greenland during a 30 year period (1978/79-2007/08) when the climate experienced increasing temperatures and precipitation. The 30-year simulations quantify the terrestrial freshwater and sediment output from part of the Greenland Ice Sheet (GrIS) and the land between the GrIS and the ocean, in the context of global warming and increasing GrIS surface melt. We used a snow-evolution modeling system (SnowModel) to simulate the winter accumulation and summer ablation processes, including runoff and surface mass balance (SMB), of the Greenland icemore » sheet. Observed sediment concentrations were related to observed runoff, producing a sediment-load time series. To a large extent, the SMB fluctuations could be explained by changes in net precipitation (precipitation minus evaporation and sublimation), with 8 out of 30 years having negative SMB, mainly because of relatively low annual net precipitation. The overall trend in net precipitation and runoff increased significantly, while 5MB increased insignificantly throughout the simulation period, leading to enhanced precipitation of 0.59 km{sup 3} w.eq. (or 60%), runoff of 0.43 km{sup 3} w.eq (or 54%), and SMB of 0.16 km3 w.eq. (or 86%). Runoff rose on average from 0.80 km{sup 3} w.eq. in 1978/79 to 1.23 km{sup 3} w.eq. in 2007/08. The percentage of catchment oudet runoff explained by runoff from the GrIS decreased on average {approx} 10%, indicating that catchment runoff throughout the simulation period was influenced more by precipitation and snowmelt events, and less by runoff from the GrIS. Average variations in the increasing Kangerlussuaq runoff from 1978/79 through 2007/08 seem to follow the overall variations in satellite-derived GrIS surface melt, where 64% of the variations in simulated runoff were explained by regional melt conditions on the GrIS. Throughout the simulation period, the sediment load varied from a minimum of 0.96 x 10{sup 6} t y{sup -1} in 1991/92 to a maximum of 3.52 x 10{sup 6} t y{sup -1} in 2006/07, showing an average increase of sediment load of 9.42 x 10{sup 5} t (or 72%) throughout the period.« less

75 FR 41556 - Proposed Collection Renewal; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-16

... global education in the classroom. Estimated annual number of respondents: 300. Estimated average time to... the annual World Wise Schools Conference. The information is used as a record of attendance. 2. Title... global education in the classroom. Estimated annual number of responses: 300. Estimated average time to...

Watershed characteristics and water-quality trends and loads in 12 watersheds in Gwinnett County, Georgia

USGS Publications Warehouse

Joiner, John K.; Aulenbach, Brent T.; Landers, Mark N.

2014-01-01

The U.S. Geological Survey, in cooperation with Gwinnett County Department of Water Resources, established a Long-Term Trend Monitoring (LTTM) program in 1996. The LTTM program is a comprehensive, long-term, water-quantity and water-quality monitoring program designed to document and analyze the hydrologic and water-quality conditions of selected watersheds of Gwinnett County, Georgia. Water-quality monitoring initially began in six watersheds and was expanded to another six watersheds in 2001. As part of the LTTM program, streamflow, precipitation, water temperature, specific conductance, and turbidity were measured continuously at the 12 watershed monitoring stations for water years 2004–09. In addition, discrete water-quality samples were collected seasonally from May through October (summer) and November through April (winter), including one base-flow and three stormflow event composite samples, during the study period. Samples were analyzed for nutrients (nitrogen and phosphorus), total organic carbon, trace elements (total lead and total zinc), total dissolved solids, and total suspended sediment (total suspended solids and suspended-sediment concentrations). The sampling scheme was designed to identify variations in water quality both hydrologically and seasonally. The 12 watersheds were characterized for basin slope, population density, land use for 2009, and the percentage of impervious area from 2000 to 2009. Precipitation in water years 2004–09 was about 18 percent below average, and the county experienced exceptional drought conditions and below average runoff in water years 2007 and 2008. Watershed water yields, the percentage of precipitation that results in runoff, typically are lower in low precipitation years and are higher for watersheds with the highest percentages of impervious areas. A comparison of base-flow and stormflow water-quality samples indicates that turbidity and concentrations of total ammonia plus organic nitrogen, total nitrogen, total phosphorus, total organic carbon, total lead, total zinc, total suspended solids, and suspended-sediment concentrations increased with increasing discharge at all watersheds. Specific conductance, however, decreased during stormflow at all watersheds, and total dissolved solids concentrations decreased during stormflow at a few of the watersheds. Total suspended solids and suspended-sediment concentrations typically were two orders of magnitude higher in stormflow samples, turbidities were about 1.5 orders of magnitude higher, total phosphorus and total zinc were about one order of magnitude higher, and total ammonia plus organic nitrogen, total nitrogen, total organic carbon, and total lead were about twofold higher than in base-flow samples. Seasonal patterns and long-term trends in flow-adjusted water-quality concentrations were identified for five representative constituents—total nitrogen, total phosphorus, total zinc, total dissolved solids, and total suspended solids. Seasonal patterns for all five constituents were fairly similar, with higher concentrations in the summer and lower concentrations in the winter. Significant linear long-term trends in stormflow composite concentrations were identified for 36 of the 60 constituent-watershed combinations (5 constituents multiplied by 12 watersheds) for the period of record through water year 2011. Significant trends typically were decreasing for total nitrogen, total phosphorus, total suspended solids, and total zinc and increasing for total dissolved solids. Total dissolved solids and total suspended solids trends had the largest magnitude changes per year. Stream water loads were estimated for 10 water-quality constituents. These estimates represent the cumulative effects of watershed characteristics, hydrologic processes, biogeochemical processes, climatic variability, and human influences on watershed water quality. Yields, in load per unit area, were used to compare loads from watersheds with different sizes. A load estimation approach developed for the Gwinnett County LTTM program that incorporates storm-event composited samples was used with some minor modifications. This approach employs the commonly used regression-model method. Concentrations were modeled as a function of discharge, time, season, and turbidity to improve model predictions and reduce errors in load estimates. Total suspended solids annual loads have been identified in Gwinnett County’s Watershed Protection Plan for target performance criterion. The amount of annual runoff is the primary factor in determining the amount of annual constituent loads. Below average runoff during water years 2004–09, especially during water years 2006–08, resulted in corresponding below average loads. Variations in constituent yields between watersheds appeared to be related to various watershed characteristics. Suspended sediment (total suspended solids and suspended-sediment concentrations) along with constituents transported predominately in solid phase (total phosphorus, total organic carbon, total lead, and total zinc) and total dissolved solids typically had higher yields from watersheds that had high percentages of impervious areas or high basin slope. High total nitrogen yields were also associated with watersheds with high percentages of impervious areas. Low total nitrogen, total suspended solids, total lead, and total zinc yields appear to be associated with watersheds that have a low percentage of high-density development. Total suspended solids yields were lower in drought years, water years 2007–08, from the combined effects of less runoff and the result of fewer, lower magnitude storms, which likely resulted in less surface erosion and lower stream sediment transport.

Secular and annual hydrologic effects from the Plate Boundary Observatory GPS network

NASA Astrophysics Data System (ADS)

Meertens, C. M.; Wahr, J. M.; Borsa, A. A.; Jackson, M. E.; Herring, T.

2009-12-01

The Plate Boundary Observatory (PBO) GPS network is providing accurate and spatially coherent vertical signals that can be interpreted in terms of hydrological loading and poroelastic effects from both natural and anthropogenic changes in water storage. Data used for this analysis are the precise coordinate time series produced on a daily basis by PBO Analysis Centers at New Mexico Institute of Mining and Technology and at Central Washington University and combined by the Analysis Center Coordinator at the Massachusetts Institute of Technology. These products, as well as derived velocity solutions, are made freely available from the UNAVCO Data Center in Boulder. Analysis of secular trends and annual variations in the time series was made using the analysis software of Langbein, 2008. Spatial variations in the amplitude and phase of the annual vertical component of motion allow for identification of anthropogenic effects due to water pumping, irrigation, and reservoir lake variations, and of outliers due to instrumental or other local site effects. Vertical annual signals of 8-10 mm peak-to-peak amplitude are evident at stations in the mountains of northern and central California and the Pacific Northwest. The peak annual uplift is in October and is correlated to hydrological loading effects. Mountainous areas appear to be responding elastically to the load of the water contained in surface soil, fractures, and snow. Vertical signals are highest when the water load is at a minimum. The vertical elastic hydrologic loading signal was modeled using the 0.25 degree community NOAH land-surface model (LSM) and generally fits the observed GPS signal. Addition comparisons will be made using the Mosaic LSM and the NOAA “Leaky Bucket” hydrologic model. In contrast to mountain stations that are installed principally in bedrock, stations in the valleys of California are installed in sediments. Observations from these stations show greater spatial variability ranging from almost no detectable annual signal to very large, 20-30 mm, vertical amplitudes that reach a maximum in March. Vertical signals in the valleys are the result of poroelastic effects induced by groundwater variations caused by pumping for irrigation or other purposes and are highest when groundwater is at maximum recharge level. Secular trends in the vertical time series show 1-3 mm/yr of subsidence across the western U.S. In areas of groundwater pumping the rates are up to several cm/yr showing subsidence as pumping exceeds annual recharge over a multi-year time period. In the mountainous areas where hydrologic loading is evident in the annual signals, secular trends show uplift of 1-3 mm/yr possibly due to regional drought and decreased overall water volumes that result in less load and vertical uplift. Overall, these results illustrate the potential of using GPS data to constrain hydrological models. In return, accurate hydrologic loading models will be needed to better measure and detect vertical tectonic motions at the mm-level.

Criterion 6, indicator 37 : average wage rates, annual average income, and annual injury rates in major forest employment categories

Treesearch

Kenneth Skog; Susan J. Alexander; John Bergstrom; Ken Cordell; Elizabeth Hill; James Howard; Rebecca Westby

2011-01-01

Average annual incomes for forest management and protection includes salaries for full-time permanent employees of the U.S. Department of Agriculture, Forest Service, which have increased from a median of $41,300 in 1992 to $48,200 in 2000, to $50,500 in 2006 (all in 2005$). Salary of full-time permanent employees in state forestry agencies in 1998, for entry level...

Evaluation of nonpoint-source contamination, Wisconsin: Land-use and Best-Management-Practices inventory, selected streamwater-quality data, urban-watershed quality assurance and quality control, constituent loads in rural streams, and snowmelt-runoff analysis, water year 1994

USGS Publications Warehouse

Walker, J.F.; Graczyk, D.J.; Corsi, S.R.; Owens, D.W.; Wierl, J.A.

1995-01-01

The objective of the watershed-management evaluation monitoring program in Wisconsin is to evaluate the effectiveness of best-management practices (BMP) for controlling nonpoint-source contamination in rural and urban watersheds. This report is an annual summary of the data collected for the program by the U.S Geological Survey and a report of the results of several different detailed analyses of the data. A land-use and BMP inventory is ongoing for 12 evaluation monitoring projects to track the sources of nonpoint-source pollution in each watershed and to document implementation of BMP's that may cause changes in the water quality of streams. Updated information is gathered each year, mapped, and stored in a geographic-information-system data base. Summaries of data collected during water years 1989-94 are presented. A water year is the period beginning October 1 and ending September 30; the water year is designated by the calendar year in which it ends. Suspended-sediment and total-phosphorus data (storm loads and annual loads) are summarized for eight rural sites. For all sites, the annual suspended-sediment or suspended-solids load for water year 1993 exceeded the average for the period of data collection; the minimum annual loads were transported in water year 1991 or 1992. Continuous dissolved-oxygen data were collected at seven rural sites during water year 1994. Data for water years 1990-93 are summarized and plotted in terms of percentage of time that a particular concentration is equaled or exceeded. Dissolved-oxygen concentrations in four streams were less than 9 mg/L at least 50 percent of the time, a condition that fails to meet suggested criterion for coldwater streams. The dissolved-oxygen probability curve for one of the coldwater streams is markedly different than the curves for the other streams, perhaps because of differences in aquatic biomass. Blank quality-assurance samples were collected at two of the urban evaluation monitoring sites to isolate contamination in the sample bottle, the automatic sampler and splitter, and the filtration system. Significant contamination caused excessive concentrations of dissolved chloride, alkalinity, and biochemical oxygen demand. The level of contamination may be large enough to affect data for water samples in which these analytes are present at low concentration. Further investigation is being done to determine the source of contamination and take measures to minimize its effect on the sampling. A preliminary regression analysis was done for the rural sites using data collected during water years 1989-93. Loads of suspended solids and total phosphorus in stormflow were regressed against various precipitation-related measures. The results indicate that, for most sites, changes in constituent load on the order of 40 to 50 percent could be detected with a statistical test. For two sites, the change would have to be 60 to 70 percent to be detected. A detailed comparison of snowmelt runoff and rainfall stormflow in urban and rural areas was done using data collected during water years 1985-93. For the rural sites where statistically significant differences were found between constituent loads in snowmelt and storm runoff, the loads of suspended solids and total phosphorus in snowmelt runoff were greater than those in storm runoff. For the urban sites where statistically significant differences were found between snowmelt and storm runoff, the loads of suspended solids and total phosphorus in storm runoff were greater than those in snowmelt runoff. The importance of including snowmelt runoff in designing and analyzing the effects of BMP's on streamwater quality, particularly in rural areas, is emphasized by these results.

50 CFR 218.31 - Permissible methods of taking.

Code of Federal Regulations, 2012 CFR

2012-10-01

...); (x) Melon-headed whales (Peponocephala electra)—100 (an average of 20 annually); (xi) False killer... annually); (xiv) Pygmy killer whale (Ferresa attenuatta)—50 (an average of 10 annually); (xv) Rough-toothed... method of take and the indicated number of times: (1) Level B Harassment: (i) Sperm whale (Physeter...

50 CFR 218.31 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

...); (x) Melon-headed whales (Peponocephala electra)—100 (an average of 20 annually); (xi) False killer... annually); (xiv) Pygmy killer whale (Ferresa attenuatta)—50 (an average of 10 annually); (xv) Rough-toothed... method of take and the indicated number of times: (1) Level B Harassment: (i) Sperm whale (Physeter...

A novel principal component analysis for spatially misaligned multivariate air pollution data.

PubMed

Jandarov, Roman A; Sheppard, Lianne A; Sampson, Paul D; Szpiro, Adam A

2017-01-01

We propose novel methods for predictive (sparse) PCA with spatially misaligned data. These methods identify principal component loading vectors that explain as much variability in the observed data as possible, while also ensuring the corresponding principal component scores can be predicted accurately by means of spatial statistics at locations where air pollution measurements are not available. This will make it possible to identify important mixtures of air pollutants and to quantify their health effects in cohort studies, where currently available methods cannot be used. We demonstrate the utility of predictive (sparse) PCA in simulated data and apply the approach to annual averages of particulate matter speciation data from national Environmental Protection Agency (EPA) regulatory monitors.

Long-term Sediment Accumulation in Mid-channel Bars of the Upper Reach of the Lower Mississippi River.

NASA Astrophysics Data System (ADS)

Wang, B.; Xu, Y. J.

2016-02-01

A recent study reported that about 44% of the total Mississippi River suspended load reaching the Old River Control Structure (ORCS) was trapped upstream of the Gulf of Mexico by overbank storage and channel bed aggradation. Considering an average annual sediment load of 120 million metric tons passing ORCS to the Mississippi River main channel, the trapped sediment load would be equivalent to annually rebuilding 44-km2 coastal land of 1 meter in depth, assuming a sedimentation bulk density of 1.2 tons m-3. No study has yet demonstrated such a high sediment accumulation rate within the confined river channel or on a floodplain area that surrounds the only unleeved stretch ( 30-km long) of the Lower Mississippi River downstream of ORCS. In this study, we utilized satellite images taken from 1983 to 2013 and analyzed changes in surface area of nine major mid-channel and point bars over a 130-km river reach from ORCS to Baton Rouge. Using river stage records and the estimated surface areas, we developed a stage - surface area rating curve for each of the bars and estimated changes in bar volume over time. We found that more than half of the bars have grown, while the others have shrunken in the past three decades. As a whole, there was a substantial net gain of surface area and volume accretion. Sediment trapping was most prevalent during the spring floods, especially during the period from 2007 to 2011 when two large floods occurred. This paper presents the channel morphological change and sediment accumulation rates under different flow conditions, and discusses their implications for the current understanding and practices of the Mississippi River sediment diversion.

Stratifying Tropical Fires by Land Cover: Insights into Amazonian Fires, Aerosol Loading, and Regional Deforestation

NASA Technical Reports Server (NTRS)

TenHoeve, J. E.; Remer, L. A.; Jacobson, M. Z.

2010-01-01

This study analyzes changes in the number of fires detected on forest, grass, and transition lands during the 2002-2009 biomass burning seasons using fire detection data and co-located land cover classifications from the Moderate Resolution Imaging Spectroradiometer (MODIS). We find that the total number of detected fires correlates well with MODIS mean aerosol optical depth (AOD) from year to year, in accord with other studies. However, we also show that the ratio of forest to savanna fires varies substantially from year to year. Forest fires have trended downward, on average, since the beginning of 2006 despite a modest increase in 2007. Our study suggests that high particulate matter loading detected in 2007 was likely due to a large number of savanna/agricultural fires that year. Finally, we illustrate that the correlation between annual Brazilian deforestation estimates and MODIS fires is considerably higher when fires are stratified by MODIS-derived land cover classifications.

7 CFR 760.1304 - Eligibility.

Code of Federal Regulations, 2011 CFR

2011-01-01

... in an eligible dairy operation must meet the average adjusted gross income eligibility requirements... benefit under this subpart if their annual average adjusted nonfarm income is over $500,000 as determined... Corporation A. For DELAP, the relevant period for the annual average adjusted nonfarm income is 2005 through...

7 CFR 760.1304 - Eligibility.

Code of Federal Regulations, 2010 CFR

2010-01-01

... in an eligible dairy operation must meet the average adjusted gross income eligibility requirements... benefit under this subpart if their annual average adjusted nonfarm income is over $500,000 as determined... Corporation A. For DELAP, the relevant period for the annual average adjusted nonfarm income is 2005 through...

Effects of cloud, aerosol, and ozone on surface spectral Ultraviolet and total irradiance observed in Seoul, Korea

NASA Astrophysics Data System (ADS)

Lee, Hana; Kim, Jhoon; Kim, Woogyung; Lee, Yun Gon; Cho, Hi Ku

2015-04-01

In recent years, there have been substantial attempts to model the radiative transfer for climatological and biological purposes. However, the incorporation of clouds, aerosols and ozone into the modeling process is one of the difficult tasks due to their variable transmission in both temporal and space domains. In this study we quantify the atmospheric transmissions by clouds, aerosol optical depth (AOD at 320 nm) and total ozone (Ozone) together with all skies in three solar radiation components of the global solar (GS 305-2800nm), total ultraviolet (TUV 290-363nm) and the erythemal weighted ultraviolet (EUV 290-325nm) irradiances with statistical methods using the data at Seoul. The purpose of this study also is to clarify the different characteristics between cloud, AOD and Ozone in the wavelength-dependent solar radiation components. The ozone, EUV and TUV used in this study (March 2003 - February 2014) have been measured with Dobson Spectrophotometer (Beck #124) and Brewer Spectrophotometer (SCI-TEC#148) at Yonsei University, respectively. GS, Cloud Cover (CC) are available from the Korean Meteorological Agency. The measured total (effect of cloud, aerosol, and ozone) transmissions on annual average showed 74%, 76% and 80% of GS, TUV and EUV irradiance, respectively. For the comparison of the measured values with modeled, we have also constructed a multiple linear regression model for the total transmission. The average ratio of measured to modeled total transmission were 0.94, 0.96 and 0.96 with higher measured than modeled value in the three components, respectively, The individual transmission by clouds under the constant AOD and Ozone atmosphere on average showed 68%, 71% and 76% and further the overcast clouds reduced the transmissions to the 45%, 54% and 59% of the clear sky irradiance in the GS, TUV and EUV, respectively. The annual transmissions by AOD showed on average 67%, 70% and 74% and further the high loadings 2.5-4.0 AOD reduced the transmission to 50%, 52% and 55% of clear sky irradiance under the contact cloud and ozone atmosphere in the GS, TUV and EUV, respectively. And annual average EUV transmission by Ozone was 75 % of the clear-sky value under the constant CC and AOD. In future study, we are compare OMI data with ground-based instruments in order to use measured data for scientific studies.

Concentrations and estimated loads of nutrients, mercury, and polychlorinated biphenyls in selected tributaries to Lake Michigan, 2005-6

USGS Publications Warehouse

Westenbroek, Stephen M.

2010-01-01

The Lake Michigan Mass Balance Project (LMMBP) measured and modeled the concentrations of environmentally persistent contaminants in air, river and lake water, sediment, and fish and bird tissues in and around Lake Michigan for an 18-month period spanning 1994-95. Tributary loads were calculated as part of the LMMBP. The work described in this report was designed to provide updated concentration data and load estimates for 5 nutrients, total mercury, and total polychlorinated biphenyl (PCB) at 5 of the original 11 LMMBP sampling sites. Samples were collected at five Lake Michigan tributary monitoring sites during 2005 and 2006. Annual loads calculated for the 2005-6 sampling period are as much as 50 percent lower relative to the 1994-95 time period. Differences between the loads calculated for the two time periods are likely related to a combination of (1) biases introduced by a reduced level of sampling effort, (2) differences in hydrological characteristics, and (3) actual environmental change. Estimated annual total mercury loads during 2005-6 ranged from 51 kilograms per year (kg/yr) in the Fox River to 2.2 kg/yr in the Indiana Harbor and Ship Canal. Estimated annual total PCB loads during 2005-6 ranged from 132 kg/yr in the Fox River to 6.2 kg/yr in the Grand River.

Modelling soil erosion in a Mediterranean watershed: Comparison between SWAT and AnnAGNPS models.

PubMed

Abdelwahab, O M M; Ricci, G F; De Girolamo, A M; Gentile, F

2018-06-20

In this study, the simulations generated by two of the most widely used hydrological basin-scale models, the Annualized Agricultural Non-Point Source (AnnAGNPS) and the Soil and Water Assessment Tool (SWAT), were compared in a Mediterranean watershed, the Carapelle (Apulia, Southern Italy). Input data requirements, time and efforts needed for input preparation, strength and weakness points of each model, ease of use and limitations were evaluated in order to give information to users. Models were calibrated and validated at monthly time scale for hydrology and sediment load using a four year period of observations (streamflow and suspended sediment concentrations). In the driest year, the specific sediment load measured at the outlet was 0.89 t ha -1 yr -1 , while the simulated values were 0.83 t ha -1 yr -1 and 1.99 t ha -1 yr -1 for SWAT and AnnAGNPS, respectively. In the wettest year, the specific measured sediment load was 7.45 t ha -1 yr -1 , and the simulated values were 8.27 t ha -1 yr -1 and 6.23 t ha -1 yr -1 for SWAT and AnnAGNPS, respectively. Both models showed from fair to a very good correlation between observed and simulated streamflow and satisfactory for sediment load. Results showed that most of the basin is under moderate (1.4-10 t ha -1 yr -1 ) and high-risk erosion (> 10 t ha -1 yr -1 ). The sediment yield predicted by the SWAT and AnnAGNPS models were compared with estimates of soil erosion simulated by models for Europe (PESERA and RUSLE2015). The average gross erosion estimated by the RUSLE2015 model (12.5 t ha -1 yr -1 ) resulted comparable with the average specific sediment yield estimated by SWAT (8.8 t ha -1 yr -1 ) and AnnAGNPS (5.6 t ha -1 yr -1 ), while it was found that the average soil erosion estimated by PESERA is lower than the other estimates (1.2 t ha -1 yr -1 ). Copyright © 2018 Elsevier Inc. All rights reserved.

40 CFR Appendix to Subpart G of... - Applicant Questionnaire for Modification of Secondary Treatment Requirements

Code of Federal Regulations, 2011 CFR

2011-07-01

... upon which your application for a modification is based: —BOD5 ___ mg/L —Suspended solids ___ mg/L —pH... dry weather —average wet weather —maximum —annual average BOD5 (mg/L) for the following plant flows: —minimum —average dry weather —average wet weather —maximum —annual average Suspended solids (mg/L) for the...

40 CFR Appendix to Subpart G of... - Applicant Questionnaire for Modification of Secondary Treatment Requirements

Code of Federal Regulations, 2010 CFR

2010-07-01

... upon which your application for a modification is based: —BOD5 ___ mg/L —Suspended solids ___ mg/L —pH... dry weather —average wet weather —maximum —annual average BOD5 (mg/L) for the following plant flows: —minimum —average dry weather —average wet weather —maximum —annual average Suspended solids (mg/L) for the...

Relation of Land Use to Streamflow and Water Quality at Selected Sites in the City of Charlotte and Mecklenburg County, North Carolina, 1993-98

USGS Publications Warehouse

Bales, Jerad D.; Weaver, J. Curtis; Robinson, Jerald B.

1999-01-01

Streamflow and water-quality data were collected at nine sites in the city of Charlotte and Mecklenburg County, North Carolina, during 1993–97. Six of the basins drained areas having relatively homogeneous land use and were less than 0.3 square mile in size; the other three basins had mixed land use. Atmospheric wet-deposition data were collected in three of the basins during 1997–98.Streamflow yield varied by a factor of six among the sites, despite the fact that sites were in close proximity to one another. The lowest yield occurred in a residential basin having no curbs and gutters. The variability in mean flow from these small, relatively homogeneous basins is much greater than is found in streams draining basins that are 10 square miles in size or larger. The ratio of runoff to rainfall in the developing basin appears to have increased during the study period.Low-flow suspended-sediment concentrations in the study basins were about the same magnitude as median stormflow concentrations in Piedmont agricultural basins. Sediment concentrations were higher in the mixed land-use basins and in the developing basin. Median suspended-sediment concentrations in these basins generally were an order of magnitude greater than median concentrations in the other five basins, which had stable land use.Some of the highest total nitrogen concentrations occurred in residential basins. Total nitrogen concentrations detected in this study were about twice as high as concentrations in small Piedmont streams affected by agriculture and urbanization. Most of the total nitrogen consisted of organic nitrogen at all of the sites except in two residential land- use basins. The high ammonia content of lawn fertilizer may explain the higher ammonia concentration in stormflow from residential basins.The two basins with the highest median suspended-sediment concentrations also had the highest total phosphorus concentrations. Median total phosphorus concentrations measured in this study were several times greater than median concentrations in small Piedmont streams but almost an order of magnitude less than total phosphorus concentrations in Charlotte streams during the late 1970's.Bacteria concentrations are not correlated to streamflow. The highest bacteria levels were found in 'first-flush' samples. Higher fecal coliform concentrations were associated with residential land use.Chromium, copper, lead, and zinc occurred at all sites in concentrations that exceeded the North Carolina ambient water-quality standards. The median chromium concentration in the developing basin was more than double the median concentration at any other site. As with chromium, the maximum copper concentration in the developing basin was almost an order of magnitude greater than maximum concentrations at other sites. The highest zinc concentration also occurred in the developing basin. Samples were analyzed for 121 organic compounds and 57 volatile organic compounds. Forty-five organic compounds and seven volatile organic compounds were detected. At least five compounds were detected at all sites, and 15 or more compounds were detected at all sites except two mixed land-use basins. Atrazine, carbaryl, and metolachlor were detected at eight sites, and 90 percent of all samples had measurable amounts of atrazine. About 60 percent of the samples had detectable levels of carbaryl and metolachlor. Diazinon and malathion were measured in samples from seven sites, and methyl parathion, chlorpyrifos, alachlor, and 2,4-D were detected at four or more sites. The fewest compounds were detected in the larger, mixed land-use basins. Residential basins and the developing basin had the greatest number of detections of organic compounds.The pH of wet atmospheric deposition in three Charlotte basins was more variable than the pH measured at a National Atmospheric Deposition Program (NADP)site in Rowan County. Summer pH values were significantly lower than pH measured during the remainder of the year, probably as a result of poorer air quality and different weather patterns during the summer.Concentrations of ammonia and nitrate at the Charlotte sites generally were lower than those measured at the NADP site. Summer concentrations of ammonia and nitrate at both the Charlotte and the NADP sites were significantly greater than concentrations measured during the remainder of the year, again probably reflecting poorer summertime air-quality conditions.Sediment yields at the nine sites ranged from 77 tons per square mile per year in a residential basin to 4,700 tons per square mile per year at the developing basin. Residential areas that have been built-out for several years and industrial areas appear, in general, to have the lowest sediment yields for the Charlotte study sites.Average annual yields of total nitrogen loads ranged from about 1.7 tons per square mile to 6.6 tons per square mile. Average annual total phosphorus yields for all sites except the developing basin were less than 1.4 tons per square mile. Phosphorus yield at the developing basin was 13 .4 tons per square mile per year.Biochemical oxygen demand loading in 1993 from all of the permitted wastewater-treatment facilities in Charlotte and Mecklenburg County was about 1.5 tons per day or 548 tons per year. Converting this point-source loading to an annual yield for the 528 square-mile area of Mecklenburg County is equivalent to 1.03 tons per square mile per year, or a yield much lower than any of the yields measured at the nine study sites. In other words, biochemical oxygen demand loading from nonpoint sources in Mecklenburg County probably exceeds loading from all point sources by a large amount.Loads and average annual yields were computed for five metals-chromium, copper, lead, nickel, and zinc. The highest annual average yields for all five of these metals were in the developing basin, which also had the highest annual average suspended-sediment yield of all the sites. Estimated wet-deposition watershed loadings suggest that atmospheric deposition may be an important source of some metals, including chromium, copper, lead, and zinc, in Charlotte storm water.Storm water from residential land-use basins has higher concentrations of total nitrogen, fecal coliform bacteria, and organic compounds than do other land-use types. Reductions in suspended-sediment concentrations should generally result in reduced export of phosphorus and metals. Stable land uses, such as industrial areas and built-out residential basins, have lower sediment concentrations in stormwater than do mixed land use and developing basins. Finally, atmospheric deposition may be an important source of nitrogen and some metals in Charlotte stormwater.

Concentrations, and estimated loads and yields of nutrients and suspended sediment in the Little River basin, Kentucky, 2003-04

USGS Publications Warehouse

Crain, Angela S.

2006-01-01

Nutrients, primarily nitrogen and phosphorus compounds, naturally occur but also are applied to land in the form of commercial fertilizers and livestock waste to enhance plant growth. Concentrations, estimated loads and yields, and sources of nitrite plus nitrate, total phosphorus, and orthophosphate were evaluated in streams of the Little River Basin to assist the Commonwealth of Kentucky in developing 'total maximum daily loads' (TMDLs) for streams in the basin. The Little River Basin encompasses about 600 square miles in Christian and Trigg Counties, and a portion of Caldwell County in western Kentucky. Water samples were collected in streams in the Little River Basin during 2003-04 as part of a study conducted in cooperation with the Kentucky Department of Agriculture. A total of 92 water samples were collected at four fixed-network sites from March through November 2003 and from February through November 2004. An additional 20 samples were collected at five synoptic-network sites during the same period. Median concentrations of nitrogen, phosphorus, and suspended sediment varied spatially and seasonally. Concentrations of nitrogen were higher in the spring (March-May) after fertilizer application and runoff. The highest concentration of nitrite plus nitrate-5.7 milligrams per liter (mg/L)-was detected at the South Fork Little River site. The Sinking Fork near Cadiz site had the highest median concentration of nitrite plus nitrate (4.6 mg/L). The North Fork Little River site and the Little River near Cadiz site had higher concentrations of orthophosphate in the fall and lower concentrations in the spring. Concentrations of orthophosphate remained high during the summer (June-August) at the North Fork Little River site possibly because of the contribution of wastewater effluent to streamflow. Fifty-eight percent of the concentrations of total phosphorus at the nine sites exceeded the U.S. Environmental Protection Agency recommended maximum concentration limit of 0.1 mg/L. Concentrations of suspended sediment were highest in the spring during runoff and lowest in the fall. The highest concentration of suspended sediment (1,020 mg/L) was observed at the Sinking Fork near Cadiz site. The median concentration of suspended sediment for all sites sampled was 12 mg/L. A nonparameteric statistical test (Wilcoxson rank-sum) showed that the median concentrations of suspended sediment were not different among any of the fixed-network sites. The Little River near Cadiz site contributed larger estimated mean annual loads of nitrite plus nitrate (2,500,000 pounds per year (lb/yr)) and total phosphorus (160,000 lb/yr) than the other three fixed-network sites. Of the two main upstream tributaries from the Little River near Cadiz site, the North Fork Little River was the greatest contributor of total phosphorus to the study area with an estimated mean annual load of 107,000 lb/yr or about 64 percent of the total estimated mean annual load at the Little River near Cadiz site. The other main upstream tributary, South Fork Little River, had an estimated mean annual load of total phosphorus that was about 20 percent of the mean annual load at the Little River near Cadiz site. Estimated loads of suspended sediment were largest at the Little River near Cadiz site, where the estimated mean annual load for 2003-04 was about 84,000,000 lb/yr. The North Fork Little River contributed an estimated 36 percent of the mean annual load of suspended sediment at the Little River near Cadiz site, while the South Fork Little River contributed an estimated 18 percent of the mean annual load at the Little River near Cadiz site. The North Fork Little River site had the largest estimated mean annual yield of total phosphorus (1,600 pounds per year per square mile (lb/yr/mi2)) and orthophosphate (1,100 lb/yr/mi2). A principal source of phosphorus for the North Fork Little River is discharge from wastewater-treatment facilities. The largest estimated mean annual yield of nitrite plus nitrate was observed at the South Fork Little River site. The North Fork Little River site had the largest estimated mean annual yield of suspended sediment (450,000 lb/yr/mi2). Inputs of nitrogen and phosphorus to streams from point and nonpoint sources were estimated for the Little River Basin. Commercial fertilizer and livestock-waste applications on row crops are a principal source of nutrients for most of the Little River Basin. Sources of nutrients in the urban areas of the basin mainly are from effluent discharge from wastewater-treatment facilities and fertilizer applications to lawns and golf courses.

Farmland-atmosphere feedbacks amplify decreases in diffuse nitrogen pollution in a freeze-thaw agricultural area under climate warming conditions.

PubMed

Gao, Xiang; Ouyang, Wei; Hao, Zengchao; Shi, Yandan; Wei, Peng; Hao, Fanghua

2017-02-01

Although climate warming and agricultural land use changes are two of the primary instigators of increased diffuse pollution, they are usually considered separately or additively. This likely lead to poor decisions regarding climate adaptation. Climate warming and farmland responses have synergistic consequences for diffuse nitrogen pollution, which are hypothesized to present different spatio-temporal patterns. In this study, we propose a modeling framework to simulate the synergistic impacts of climate warming and warming-induced farmland shifts on diffuse pollution. Active accumulated temperature response for latitudinal and altitudinal directions was predicted based on a simple agro-climate model under different temperature increments (△T 0 is from 0.8°C to 1.4°C at an interval of 0.2°C). Spatial distributions of dryland shift to paddy land were determined by considering accumulated temperature. Different temperature increments and crop distributions were inserted into Soil and Water Assessment Tool model, which quantified the spatio-temporal changes of nitrogen. Warming led to a decrease of the annual total nitrogen loading (2.6%-14.2%) in the low latitudes compared with baseline, which was larger than the decrease (0.8%-6.2%) in the high latitudes. The synergistic impacts amplified the decrease of the loading in the low and high latitudes at the sub-basin scale. Warming led to a decrease of the loading at a rate of 0.35kg/ha/°C, which was lower than the synergistic impacts (3.67kg/ha/°C) at the watershed level. However, warming led to the slight increase of the annual averaged NO3 (LAT) (0.16kg/ha/°C), which was amplified by the synergistic impacts (0.22kg/ha/°C). Expansion of paddy fields led to a decrease in the monthly total nitrogen loading throughout the year, but amplified an increase in the loading in August and September. The decreased response in spatio-temporal nitrogen patterns is substantially amplified by farmland-atmosphere feedbacks associated with farmland shifts in response to warming. Copyright © 2016 Elsevier B.V. All rights reserved.

Long-Term Wet and Dry Deposition of Total and Methyl Mercury in the Remote Boreal Ecoregion of Canada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Graydon, Jennifer A; Louis, Vincent; Hintelmann, Holger

2008-11-01

Although a positive relationship between atmospheric loadings of inorganic mercury (Hg(II)) to watersheds and concentrations of methyl mercury (MeHg) in fish has now been established, net wet and dry deposition of Hg(II) and MeHg to watersheds remains challenging to quantify. In this study, concentrations and loadings of total mercury (THg; all forms of Hg in a sample) and MeHg in open area wet deposition, throughfall, and litterfall were quantified at the remote Experimental Lakes Area in the boreal ecoregion, NW Ontario, Canada. Between 1992 and 2006, mean annual THg and MeHg loadings in the open were 36 17 and 0.5more » 0.2 mg ha 1, respectively. Throughfall THg and MeHg loadings were generally 2 4 times and 0.8 2 times higher, respectively, than loadings in the open. Loadings of both THg and MeHg were highest under an old growth spruce/fir canopy and lowest under a deciduous maple canopy, whereas loadings under young jack pine and wetland spruce/pine/alder canopies were intermediate. Litterfall generally represented the largest input of THg (86 105 mg ha 1) and MeHg (0.7 0.8 mg ha 1) to the landscape on an annual basis. Using the direct method of estimating dry deposition (thoughfall + litterfall open loadings), we calculated that annual dry deposition of THg and MeHg under forest canopies ranged from 105 to 201 mg ha 1, whereas dry deposition of MeHg ranged from 0.7 to 1.2 mg ha 1. Photoreduction and emission of wet-deposited Hg(II) from canopy foliage were accounted for, resulting in 3 5% (5 6 mg ha 1) higher annual estimates of dry deposition than via the direct method alone. Net THg and MeHg loadings to this remote landscape were lower than at any other previously studied forested site globally. This study shows that THg and MeHg loading can be extremely variable within a heterogeneous boreal landscape and that processes such as Hg photoreduction and emission from foliage should be considered when estimating dry deposition of Hg.« less

Effective control measures at high particulate pollution areas : analysis of data from the 2000 Phoenix Greenwood study

DOT National Transportation Integrated Search

2005-02-01

Annual average PM10 concentrations at the Greenwood monitoring station in western Phoenix have : exceeded EPAs annual average air quality standard and are higher on average than values observed at the : West Phoenix monitor, which is located just ...

ERROR IN ANNUAL AVERAGE DUE TO USE OF LESS THAN EVERYDAY MEASUREMENTS

EPA Science Inventory

Long term averages of the concentration of PM mass and components are of interest for determining compliance with annual averages, for developing exposure surrogated for cross-sectional epidemiologic studies of the long-term of PM, and for determination of aerosol sources by chem...

40 CFR 464.34 - New source performance standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-continuous dischargers, annual average mass standards and maximum day and maximum for monthly average concentration (mg/l) standards shall apply. Concentration standards and annual average mass standards shall only... 40 Protection of Environment 31 2012-07-01 2012-07-01 false New source performance standards. 464...

40 CFR 464.34 - New source performance standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

...-continuous dischargers, annual average mass standards and maximum day and maximum for monthly average concentration (mg/l) standards shall apply. Concentration standards and annual average mass standards shall only... 40 Protection of Environment 30 2014-07-01 2014-07-01 false New source performance standards. 464...

40 CFR 464.34 - New source performance standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

...-continuous dischargers, annual average mass standards and maximum day and maximum for monthly average concentration (mg/l) standards shall apply. Concentration standards and annual average mass standards shall only... 40 Protection of Environment 31 2013-07-01 2013-07-01 false New source performance standards. 464...

24 CFR 235.204 - Amount of annual MIP.

Code of Federal Regulations, 2010 CFR

2010-04-01

... and Obligations-Homes for Lower Income Families § 235.204 Amount of annual MIP. (a) With respect to... an annual MIP shall be paid in an amount equal to one-half percent of the average outstanding... be paid in an amount equal to seven-tenths of one percent of the average outstanding principal...

24 CFR 235.204 - Amount of annual MIP.

Code of Federal Regulations, 2011 CFR

2011-04-01

... and Obligations-Homes for Lower Income Families § 235.204 Amount of annual MIP. (a) With respect to... an annual MIP shall be paid in an amount equal to one-half percent of the average outstanding... be paid in an amount equal to seven-tenths of one percent of the average outstanding principal...

Analysis of Nitrogen Loads From Long Island Sound Watersheds, 1988-98

NASA Astrophysics Data System (ADS)

Mullaney, J. R.; Trench, E. C.

2001-05-01

The U.S. Geological Survey (USGS) recently estimated annual nonpoint-source nitrogen loads from watersheds that drain to Long Island Sound. The study, was conducted in cooperation with the Connecticut Department of Environmental Protection, the New York State Department of Environmental Conservation and the U.S. Environmental Protection Agency, to assist these agencies with the issue of low concentrations of dissolved oxygen in Long Island Sound caused by nitrogen enrichment. A regression model was used to determine annual nitrogen loads at 27 streams monitored by the USGS during 1988-98. Estimates of nitrogen loads from municipal wastewater-treatment plants (where applicable) were subtracted from the total nitrogen loads to determine the nonpoint-source nitrogen load for each water-quality monitoring station. The nonpoint-source load information was applied to unmonitored areas by comparing the land-use and land-cover characteristics of monitored areas with unmonitored areas, and selecting basins that were most similar. In extrapolating load estimates to unmonitored areas, regional differences in mean annual runoff between monitored and unmonitored areas also were considered, using flow information from nearby USGS gaging stations. Estimates of nonpoint nitrogen loads from monitored areas with point sources of nitrogen discharge and estimates from unmonitored areas are subject to uncertainty. These estimates could be improved with additional data collection in coastal basins and in basins with a large percentage of urbanized land, measurements of instream transformation or losses of nitrogen, improved reporting of total nitrogen concentrations from municipal wastewater treatment facilities, and tracking of intrabasin and (or) interbasin diversion of water.

Nutrient Loadings to Streams of the Continental United States from Municipal and Industrial Effluent

USGS Publications Warehouse

Maupin, M.A.; Ivahnenko, T.

2011-01-01

Data from the United States Environmental Protection Agency Permit Compliance System national database were used to calculate annual total nitrogen (TN) and total phosphorus (TP) loads to surface waters from municipal and industrial facilities in six major regions of the United States for 1992, 1997, and 2002. Concentration and effluent flow data were examined for approximately 118,250 facilities in 45 states and the District of Columbia. Inconsistent and incomplete discharge locations, effluent flows, and effluent nutrient concentrations limited the use of these data for calculating nutrient loads. More concentrations were reported for major facilities, those discharging more than 1million gallons per day, than for minor facilities, and more concentrations were reported for TP than for TN. Analytical methods to check and improve the quality of the Permit Compliance System data were used. Annual loads were calculated using "typical pollutant concentrations" to supplement missing concentrations based on the type and size of facilities. Annual nutrient loads for over 26,600 facilities were calculated for at least one of the three years. Sewage systems represented 74% of all TN loads and 58% of all TP loads. This work represents an initial set of data to develop a comprehensive and consistent national database of point-source nutrient loads. These loads can be used to inform a wide range of water-quality management, watershed modeling, and research efforts at multiple scales. ?? 2011 American Water Resources Association. This article is a U.S. Government work and is in the public domain in the USA.

Onchocerciasis control in Nigeria: will households be able to afford community-directed treatment with ivermectin?

PubMed

Onwujekwe, O; Shu, E; Onwuameze, O; Ndum, C; Okonkwo, P

2001-12-21

To determine the level of affordability of community-directed treatment with ivermectin (CDTI) to households living in two onchocerciasis endemic Nigerian communities namely Toro in the north and Nike in the south. The proportion of the cost of treating people with ivermectin will deplete in average monthly/projected annual household expenditure on food and health care, and on average monthly and projected annual household income were respectively calculated and used to determine the level of affordability of CDTI. Questionnaires administered to heads of households or their representatives were used to collect information on the household expenditures and income. The suggested unit CDTI cost of $0.20 was used. However, as a test of sensitivity, we also used the unit cost of $0.056 which some community based distributors are charging per treatment. Using $0.20 as the unit treatment cost, this will consume less than 0.05% of average annual household income in both communities. It will equally deplete 0.05% of combined annual household expenditures on food and health care in both communities. However, using $0.056 as the unit treatment cost, then 0.02% of average annual household expenditure on health care, 0.01% average annual expenditure on combined health care and food, and 0.01% of average annual household income will be depleted. The households living in both communities may be able to afford CDTI schemes. However, the final decision on levels of affordability lies with the households. They will decide whether they can afford to trade-off some household income for ivermectin distribution.

2006 Pacific Northwest Loads and Resources Study.

DOE Office of Scientific and Technical Information (OSTI.GOV)

United States. Bonneville Power Administration.

2006-03-01

The Pacific Northwest Loads and Resources Study (White Book), which is published annually by the Bonneville Power Administration (BPA), establishes one of the planning bases for supplying electricity to customers. The White Book contains projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. The White Book also contains information obtained from formalized resource planning reports and data submittals including those from individual utilities, the Northwest Power and Conservation Council (Council), and the Pacific Northwest Utilities Conference Committee (PNUCC). The White Book is not an operational planning guide, nor is it used for determiningmore » BPA revenues, although the database that generates the data for the White Book analysis contributes to the development of BPA's inventory and ratemaking processes. Operation of the Federal Columbia River Power System (FCRPS) is based on a set of criteria different from that used for resource planning decisions. Operational planning is dependent upon real-time or near-term knowledge of system conditions that include expectations of river flows and runoff, market opportunities, availability of reservoir storage, energy exchanges, and other factors affecting the dynamics of operating a power system. The load resource balance of both the Federal system and the region is determined by comparing resource availability to an expected level of total retail electricity consumption. Resources include projected energy capability plus contract purchases. Loads include a forecast of retail obligations plus contract obligations. Surplus energy is available when resources are greater than loads. This surplus energy could be marketed to increase revenues. Energy deficits occur when resources are less than loads. These energy deficits will be met by any combination of the following: better-than-critical water conditions, demand-side management and conservation programs, permanent loss of loads due to economic conditions or closures, additional contract purchases, and/or the addition of new generating resources. This study incorporates information on Pacific Northwest (PNW) regional retail loads, contract obligations, and contract resources. This loads and resources analysis simulates the operation of the power system in the PNW. The simulated hydro operation incorporates plant characteristics, streamflows, and non-power requirements from the current Pacific Northwest Coordination Agreement (PNCA). Additional resource capability estimates were provided by BPA, PNW Federal agency, public agency, cooperative, U.S. Bureau of Reclamation (USBR), and investor-owned utility (IOU) customers furnished through annual PNUCC data submittals for 2005 and/or direct submittals to BPA. The 2006 White Book is presented in two documents: (1) this summary document of Federal system and PNW region loads and resources, and (2) a technical appendix which presents regional loads, grouped by major PNW utility categories, and detailed contract and resource information. The technical appendix is available only in electronic form. Individual customer information for marketer contracts is not detailed due to confidentiality agreements. The 2006 White Book analysis updates the 2004 White Book. This analysis shows projections of the Federal system and region's yearly average annual energy consumption and resource availability for the study period, OY 2007-2016. The study also presents projections of Federal system and region expected 1-hour monthly peak demand, monthly energy demand, monthly 1-hour peak generating capability, and monthly energy generation for OY 2007, 2011, and 2016. BPA is investigating a new approach in capacity planning depicting the monthly Federal system 120-hour peak generating capability and 120-hour peak surplus/deficit for OY 2007, 2011, and 2016. This document analyzes the PNW's projected loads and available generating resources in two parts: (1) the loads and resources of the Federal system, for which BPA is the marketing agency; and (2) the larger PNW regional power system loads and resources that include the Federal system as well other PNW entities.« less

78 FR 19262 - Notice of Annual Adjustment of the Cap on Average Total Assets That Defines Community Financial...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-29

... FEDERAL HOUSING FINANCE AGENCY [No. 2013-N-04] Notice of Annual Adjustment of the Cap on Average.... ACTION: Notice. SUMMARY: The Federal Housing Finance Agency (FHFA) has adjusted the cap on average total... Federal Deposit Insurance Corporation and that has average total assets below a statutory cap.\\2\\ The Bank...

75 FR 9601 - Notice of Annual Adjustment of the Cap on Average Total Assets That Defines Community Financial...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-03

... FEDERAL HOUSING FINANCE AGENCY [No. 2010-N-01] Notice of Annual Adjustment of the Cap on Average.... ACTION: Notice. SUMMARY: The Federal Housing Finance Agency (FHFA) has adjusted the cap on average total... Deposit Insurance Corporation and that has average total assets below a statutory cap. See 12 U.S.C. 1422...

26 CFR 1.411(d)-3 - Section 411(d)(6) protected benefits.

Code of Federal Regulations, 2011 CFR

2011-04-01

... an annual benefit of 2% of career average pay times years of service commencing at normal retirement... an annual benefit of 1.3% of final pay times years of service, with final pay computed as the average... has 16 years of service, M's career average pay is $37,500, and the average of M's highest 3...

A comparison of hydrological deformation using GPS and global hydrological model for the Eurasian plate

NASA Astrophysics Data System (ADS)

Li, Zhen; Yue, Jianping; Li, Wang; Lu, Dekai; Li, Xiaogen

2017-08-01

The 0.5° × 0.5° gridded hydrological loading from Global Land Surface Discharge Model (LSDM) mass distributions is adopted for 32 GPS sites on the Eurasian plate from January 2010 to January 2014. When the heights of these sites that have been corrected for the effects of non-tidal atmospheric and ocean loading are adjusted by the hydrological loading deformation, more than one third of the root-mean-square (RMS) values of the GPS height variability become larger. After analyzing the results by continuous wavelet transform (CWT) and wavelet transform coherence (WTC), we confirm that hydrological loading primarily contributes to the annual variations in GPS heights. Further, the cross wavelet transform (XWT) is used to investigate the relative phase between the time series of GPS heights and hydrological deformation, and it is indicated that the annual oscillations in the two time series are physically related for some sites; other geophysical effect, GPS systematic errors and hydrological modeling errors could result in the phase asynchrony between GPS and hydrological loading signals for the other sites. Consequently, the phase asynchrony confirms that the annual fluctuations in GPS observations result from a combination of geophysical signals and systematic errors.

Modelling of different measures for improving removal in a stormwater pond.

PubMed

German, J; Jansons, K; Svensson, G; Karlsson, D; Gustafsson, L G

2005-01-01

The effect of retrofitting an existing pond on removal efficiency and hydraulic performance was modelled using the commercial software Mike21 and compartmental modelling. The Mike21 model had previously been calibrated on the studied pond. Installation of baffles, the addition of culverts under a causeway and removal of an existing island were all studied as possible improvement measures in the pond. The subsequent effect on hydraulic performance and removal of suspended solids was then evaluated. Copper, cadmium, BOD, nitrogen and phosphorus removal were also investigated for that specific improvement measure showing the best results. Outcomes of this study reveal that all measures increase the removal efficiency of suspended solids. The hydraulic efficiency is improved for all cases, except for the case where the island is removed. Compartmental modelling was also used to evaluate hydraulic performance and facilitated a better understanding of the way each of the different measures affected the flow pattern and performance. It was concluded that the installation of baffles is the best of the studied measures resulting in a reduction in the annual load on the receiving lake by approximately 8,000 kg of suspended solids (25% reduction of the annual load), 2 kg of copper (10% reduction of the annual load) and 600 kg of BOD (10% reduction of the annual load).

50 CFR 218.122 - Permissible methods of taking.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: (A) Sperm whales (Physeter macrocephalus)—1,645 (an average of 329 annually); (B) Killer whale... the rule must be maintained. (4) Level B Harassment: (i) Mysticetes: (A) Humpback whale (Megaptera novaeangliae)—6,975 (an average of 1,395 annually); (B) Fin whale (Balaenoptera physalus)—55185 (an average of...

50 CFR 218.122 - Permissible methods of taking.

Code of Federal Regulations, 2014 CFR

2014-10-01

...: (A) Sperm whales (Physeter macrocephalus)—1,645 (an average of 329 annually); (B) Killer whale... the rule must be maintained. (4) Level B Harassment: (i) Mysticetes: (A) Humpback whale (Megaptera novaeangliae)—6,975 (an average of 1,395 annually); (B) Fin whale (Balaenoptera physalus)—55185 (an average of...

50 CFR 218.122 - Permissible methods of taking.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: (A) Sperm whales (Physeter macrocephalus)—1,645 (an average of 329 annually); (B) Killer whale... the rule must be maintained. (4) Level B Harassment: (i) Mysticetes: (A) Humpback whale (Megaptera novaeangliae)—6,975 (an average of 1,395 annually); (B) Fin whale (Balaenoptera physalus)—55185 (an average of...

Evaluation of atmospheric nitrogen deposition model performance in the context of U.S. critical load assessments

NASA Astrophysics Data System (ADS)

Williams, Jason J.; Chung, Serena H.; Johansen, Anne M.; Lamb, Brian K.; Vaughan, Joseph K.; Beutel, Marc

2017-02-01

Air quality models are widely used to estimate pollutant deposition rates and thereby calculate critical loads and critical load exceedances (model deposition > critical load). However, model operational performance is not always quantified specifically to inform these applications. We developed a performance assessment approach designed to inform critical load and exceedance calculations, and applied it to the Pacific Northwest region of the U.S. We quantified wet inorganic N deposition performance of several widely-used air quality models, including five different Community Multiscale Air Quality Model (CMAQ) simulations, the Tdep model, and 'PRISM x NTN' model. Modeled wet inorganic N deposition estimates were compared to wet inorganic N deposition measurements at 16 National Trends Network (NTN) monitoring sites, and to annual bulk inorganic N deposition measurements at Mount Rainier National Park. Model bias (model - observed) and error (|model - observed|) were expressed as a percentage of regional critical load values for diatoms and lichens. This novel approach demonstrated that wet inorganic N deposition bias in the Pacific Northwest approached or exceeded 100% of regional diatom and lichen critical load values at several individual monitoring sites, and approached or exceeded 50% of critical loads when averaged regionally. Even models that adjusted deposition estimates based on deposition measurements to reduce bias or that spatially-interpolated measurement data, had bias that approached or exceeded critical loads at some locations. While wet inorganic N deposition model bias is only one source of uncertainty that can affect critical load and exceedance calculations, results demonstrate expressing bias as a percentage of critical loads at a spatial scale consistent with calculations may be a useful exercise for those performing calculations. It may help decide if model performance is adequate for a particular calculation, help assess confidence in calculation results, and highlight cases where a non-deterministic approach may be needed.

Spatiotemporal distribution and the characteristics of the air temperature of a river source region of the Qinghai-Tibet Plateau.

PubMed

Deng, Cai; Zhang, Wanchang

2018-05-30

As the backland of the Qinghai-Tibet Plateau, the river source region is highly sensitive to changes in global climate. Air temperature estimation using remote sensing satellite provides a new way of conducting studies in the field of climate change study. A geographically weighted regression model was applied to estimate synchronic air temperature from 2001 to 2015 using Moderate-Resolution Imaging Spectroradiometry (MODIS) data. The results were R 2  = 0.913 and RMSE = 2.47 °C, which confirmed the feasibility of the estimation. The spatial distribution and variation characteristics of the average annual and seasonal air temperature were analyzed. The findings are as follows: (1) the distribution of average annual air temperature has significant terrain characteristics. The reduction in average annual air temperature along the elevation of the region is 0.19 °C/km, whereas the reduction in the average annual air temperature along the latitude is 0.04 °C/degree. (2) The average annual air temperature increase in the region is 0.37 °C/decade. The average air temperature increase could be arranged in the following decreasing order: Yangtze River Basin > Mekong River Basin > Nujiang River Basin > Yarlung Zangbo River Basin > Yellow River Basin. The fastest, namely, Yangtze River Basin, is 0.47 °C/decade. (3) The average air temperature rise in spring, summer, and winter generally increases with higher altitude. The average annual air temperature in different types of lands following a decreasing order is as follows: wetland > construction land > bare land glacier > shrub grassland > arable land > forest land > water body and that of the fastest one, wetland, is 0.13 °C/year.

Magnitudes, nature, and effects of point and nonpoint discharges in the Chattahoochee River Basin, Atlanta to West Point Dam, Georgia

USGS Publications Warehouse

Stamer, J.K.; Cherry, Rodney N.; Faye, R.E.; Kleckner, R.L.

1979-01-01

During the period April 1975 to June 1978, the U.S. Geological Survey conducted a river-quality assessment of the Upper Chattahoochee River basin in Georgia. One objective of the study was to assess the magnitudes, nature, and effects of point and non-point discharges in the Chattahoochee River basin from Atlanta to the West Point Dam. On an average annual basis and during the storm period of March 1215, 1976, non-point-source loads for most constituents analyzed were larger than point-source loads at the Whitesburg station, located on the Chattahoochee River about 40 river miles downstream of Atlanta. Most of the non-point-source constituent loads in the Atlanta-to-Whitesburg reach were from urban areas. Average annual point-source discharges accounted for about 50 percent of the dissolved nitrogen, total nitrogen, and total phosphorus loads, and about 70 percent of the dissolved phosphorus loads at Whitesburg. During weekends, power generation at the upstream Buford Dam hydroelectric facility is minimal. Streamflow at the Atlanta station during dry-weather weekends is estimated to be about 1,200 ft3/s (cubic feet per second). Average daily dissolved-oxygen concentrations of less than 5.0 mg/L (milligrams per liter) occurred often in the river, about 20 river miles downstream from Atlanta during these periods from May to November. During a low-flow period, June 1-2, 1977, five municipal point sources contributed 63 percent of the ultimate biochemical oxygen demand, 97 percent of the ammonium nitrogen, 78 percent of the total nitrogen, and 90 percent of the total phosphorus loads at the Franklin station, at the upstream end of West Point Lake. Average daily concentrations of 13 mg/L of ultimate biochemical oxygen demand and 1.8 mg/L of ammonium nitrogen were observed about 2 river miles downstream from two of the municipal point sources. Carbonaceous and nitrogenous oxygen demands caused dissolved-oxygen concentrations between 4.1 and 5.0 mg/L to occur in a 22-mile reach of the river downstream from Atlanta. Nitrogenous oxygen demands were greater than carbonaceous oxygen demands in the reach from river mile 303 to 271, and carbonaceous demands were greater from river mile 271 to 235. The heat load from the Atkinson-McDonough thermoelectric power-plants caused a decrease in the dissolved-oxygen concentrations of about 0.2 mg/L. During a critical low-flow period, a streamflow at Atlanta of about 1,800 ft3/s, with present (1977) point-source flows of 185 ft3/s containing concentrations of 45 mg/L of ultimate biochemical oxygen demand and 15 mg/L of ammonium nitrogen, results in a computed minimum dissolved-oxygen concentration of 4.7 mg/L in the river downstream from Atlanta. In the year 2000, a streamflow at Atlanta of about 1,800 ft3/s with point-source flows of 373 ft3/s containing concentrations of 45 mg/L of ultimate biochemical oxygen demand and 5.0 mg/L of ammonium nitrogen, will result in a computed minimum dissolved-oxygen concentration of 5.0 mg/L. A streamflow of about 1,050 ft3/s at Atlanta in the year 2000 will result in a dissolved-oxygen concentration of 5.0 mg/L if point-source flows contain concentrations of 15 mg/L of ultimate biochemical oxygen demand and 5.0 mg/L of ammonium nitrogen. Phytoplankton concentrations in West Point Lake, about 70 river miles downstream from Atlanta, could exceed 3 million cells per milliliter during extended low-flow periods in the summer with present point- and non-point-source nitrogen and phosphorus loads. In the year 2000, phytoplankton concentrations in West Point Lake are not likely to exceed 700,000 cells per milliliter during extended low-flow periods in the summer, if phosphorus concentrations do not exceed 1.0 mg/L in point-source discharges.

Precipitation-runoff, suspended-sediment, and flood-frequency characteristics for urbanized areas of Elmendorf Air Force Base, Alaska

USGS Publications Warehouse

Brabets, Timothy P.

1999-01-01

The developed part of Elmendorf Air Force Base near Anchorage, Alaska, consists of two basins with drainage areas of 4.0 and 0.64 square miles, respectively. Runoff and suspended-sediment data were collected from August 1996 to March 1998 to gain a basic understanding of the surface-water hydrology of these areas and to estimate flood-frequency characteristics. Runoff from the larger basin averaged 6 percent of rainfall, whereas runoff from the smaller basin averaged 13 percent of rainfall. During rainfall periods, the suspended-sediment load transported from the larger watershed ranged from 179 to 21,000 pounds and that from the smaller watershed ranged from 23 to 18,200 pounds. On a yield basis, suspended sediment from the larger watershed was 78 pounds per inch of runoff and from the smaller basin was 100 pounds per inch of runoff. Suspended-sediment loads and yields were generally lower during snowmelt periods than during rainfall periods. At each outfall of the two watersheds, water flows into steep natural channels. Suspended-sediment loads measured approximately 1,000 feet downstream from the outfalls during rainfall periods ranged from 8,450 to 530,000 pounds. On a yield basis, suspended sediment averaged 705 pounds per inch of runoff, more than three times as much as the combined sediment yield from the two watersheds. The increase in suspended sediment is most likely due to natural erosion of the streambanks. Streamflow data, collected in 1996 and 1997, were used to calibrate and verify a U.S. Geological Survey computer model?the Distributed Routing Rainfall Runoff Model-Version II (DR3M-II). The model was then used to simulate annual peak discharges and runoff volumes for 1981 to 1995 using historical rainfall records. Because the model indicated that surcharging (or ponding) would occur, no flood-frequency analysis was done for peak discharges. A flood-frequency analysis of flood volumes indicated that a 10-year flood would result in 0.39 inch of runoff (averaged over the entire drainage basin) from the larger watershed and 1.1 inches of runoff from the smaller watershed.

Assessing the Impacts of Land Use Change from Cotton to Perennial Bioenergy Grasses on Hydrological Fluxes and Water Quality in a Semi-Arid Agricultural Watershed Using the APEX Model

NASA Astrophysics Data System (ADS)

Chen, Y.; Ale, S.; Rajan, N.

2015-12-01

The semi-arid Texas High Plains (THP) region, where cotton (Gossypium hirsutum L.) is grown in vast acreage, has the potential to grow perennial bioenergy grasses. A change in land use from cotton cropping systems to perennial grasses such as Alamo switchgrass (Panicum virgatum L.) and Miscanthus giganteus (Miscanthus sinensis Anderss. [Poaceae]) can significantly affect regional hydrologic cycle and water quality. Assessing the impacts of this potential land use change on hydrology and water quality enables the environmental assessment of feasibility to grow perennial grasses in this region to meet the U.S. national bioenergy target of 2022. The Agricultural Policy/Environmental eXtender (APEX) model was used in this study to assess the impacts of replacing cotton with switchgrass and Miscanthus on water and nitrogen balances in the upstream subwatershed of the Double Mountain Fork Brazos watershed in the THP, which contains 52% cotton land use. The APEX model was initially calibrated against observed streamflow and crop yield data. Since observed data on nitrogen loads in streamflow was not available for this subwatershed, we calibrated the APEX model against the SWAT-simulated nitrogen loads at the outlet of this subwatershed, which were obtained in a parallel study. The calibrated APEX model was used to simulate the impacts of land use change from cotton to Miscanthus and switchgrass on surface and subsurface water and nitrogen balances. Preliminary results revealed that the average (1994-2009) annual surface runoff decreased by 84% and 66% under the irrigated and dryland switchgrass scenarios compared to the baseline scenarios. Average annual percolation increased by 106% and 57% under the irrigated and dryland switchgrass scenarios relative to the baseline scenarios. Preliminary results also indicated Miscanthus and switchgrass appeared to be superior to cotton in terms of better water conservation and water quality, and minimum crop management requirements.

Water-quality variability and constituent transport and processes in streams of Johnson County, Kansas, using continuous monitoring and regression models, 2003-11

USGS Publications Warehouse

Rasmussen, Teresa; Gatotho, Jackline

2014-01-01

The population of Johnson County, Kansas increased by about 24 percent between 2000 and 2012, making it one of the most rapidly developing areas of Kansas. The U.S. Geological Survey, in cooperation with the Johnson County Stormwater Management Program, began a comprehensive study of Johnson County streams in 2002 to evaluate and monitor changes in stream quality. The purpose of this report is to describe water-quality variability and constituent transport for streams representing the five largest watersheds in Johnson County, Kansas during 2003 through 2011. The watersheds ranged in urban development from 98.3 percent urban (Indian Creek) to 16.7 percent urban (Kill Creek). Water-quality conditions are quantified among the watersheds of similar size (50.1 square miles to 65.7 square miles) using continuous, in-stream measurements, and using regression models developed from continuous and discrete data. These data are used to quantify variability in concentrations and loads during changing streamflow and seasonal conditions, describe differences among sites, and assess water quality relative to water-quality standards and stream management goals. Water quality varied relative to streamflow conditions, urbanization in the upstream watershed, and contributions from wastewater treatment facilities and storm runoff. Generally, as percent impervious surface (a measure of urbanization) increased, streamflow yield increased. Water temperature of Indian Creek, the most urban site which is also downstream from wastewater facility discharges, was higher than the other sites about 50 percent of the time, particularly during winter months. Dissolved oxygen concentrations were less than the Kansas Department of Health and Environment minimum criterion of 5 milligrams per liter about 15 percent of the time at the Indian Creek site. Dissolved oxygen concentrations were less than the criterion about 10 percent of the time at the rural Blue River and Kill Creek sites, and less than 5 percent of the time at the other sites. Low dissolved oxygen at all sites generally coincided with lowest streamflow and warmer water temperatures. Hourly dissolved oxygen concentrations less than 5 milligrams per liter were measured at all sites every year, indicating that even under normal climate conditions in non-urban watersheds such as Kill Creek, dissolved oxygen concentrations may not meet State aquatic-life criterion. Specific conductance was nearly always highest in Indian and Mill Creeks, which were the most urban streams with the largest upstream discharges from wastewater treatment facilities. The largest chloride concentrations and variability were recorded at urban sites and during winter. Each winter during the study period, chloride concentrations in the most urban site, Indian Creek, exceeded the U.S. Environmental Protection Agency-recommended criterion of 230 milligrams per liter for at least 10 consecutive days. The U.S. Environmental Protection Agency-recommended ecoregion criterion for turbidity was exceeded 30 (Indian Creek) to 50 (Blue River) percent of the time. The highest average annual streamflow-weighted suspendedsediment concentration during the study period was in Mill Creek, which has undergone rapid development that likely contributed to higher sediment concentrations. One of the largest suspended-sediment load events in Indian Creek was recorded in early May 2007 when about 25 percent of the total annual sediment load was transported during a period of about 2.25 days. A simultaneous load event was recorded in Kill Creek, when about 75 percent of the total annual sediment load was transported. Sediment yields generally increased as percent impervious surface increased. Computed hourly total nitrogen and total phosphorus concentrations and yields and streamflow-weighted concentrations generally were largest in Indian and Mill Creeks. Annual percent contribution of total nitrogen in the Blue River from wastewater treatment facility discharges ranged from 19 percent in 2010 to 60 percent in 2006. Annual percent contribution of total nitrogen in Indian Creek from wastewater treatment facility discharges ranged from 35 percent in 2010 to 93 percent in 2006. The largest percent nutrient contributions from wastewater discharges coincided with the smallest annual precipitation and streamflow volume, resulting in less contribution originating from runoff. Fecal indicator bacteria Escherichia coli density at the urban Indian Creek site was usually the largest of the five monitoring sites, with an annual median density that consistently exceeded the State primary contact criterion value but was less than the secondary contact criterion. Less than 1 percent of the total annual bacteria load in the Blue River and Indian Creek originated from wastewater discharges, except during 2006 when about 6 percent of the Indian Creek load originated from wastewater. Continuous water-quality monitoring provides a foundation for comprehensive evaluation and understanding of variability and loading characteristics in streams in Johnson County. Because several directly measured parameters are strongly correlated with particular constituents of interest, regression models provide a valuable tool for evaluating variability and loading on the basis of computed continuous data. Continuous data are particularly useful for characterizing nonpoint-source contributions from stormwater runoff. Transmission of continuous data in real-time makes it possible to rapidly detect and respond to potential environmental concerns. As monitoring technologies continue to improve, so does the ability to monitor additional constituents of interest, with smaller measurement error, and at lower operational cost. Continuous water-quality data including model information and computed concentrations and loads during the study period are available at http://nrtwq.usgs.gov/ks/.

Application of a Three-Dimensional Water Quality Model as a Decision Support Tool for the Management of Land-Use Changes in the Catchment of an Oligotrophic Lake

NASA Astrophysics Data System (ADS)

Trolle, Dennis; Spigel, Bob; Hamilton, David P.; Norton, Ned; Sutherland, Donna; Plew, David; Allan, Mathew G.

2014-09-01

While expansion of agricultural land area and intensification of agricultural practices through irrigation and fertilizer use can bring many benefits to communities, intensifying land use also causes more contaminants, such as nutrients and pesticides, to enter rivers, lakes, and groundwater. For lakes such as Benmore in the Waitaki catchment, South Island, New Zealand, an area which is currently undergoing agricultural intensification, this could potentially lead to marked degradation of water clarity as well as effects on ecological, recreational, commercial, and tourism values. We undertook a modeling study to demonstrate science-based options for consideration of agricultural intensification in the catchment of Lake Benmore. Based on model simulations of a range of potential future nutrient loadings, it is clear that different areas within Lake Benmore may respond differently to increased nutrient loadings. A western arm (Ahuriri) could be most severely affected by land-use changes and associated increases in nutrient loadings. Lake-wide annual averages of an eutrophication indicator, the trophic level index (TLI) were derived from simulated chlorophyll a, total nitrogen, and total phosphorus concentrations. Results suggest that the lake will shift from oligotrophic (TLI = 2-3) to eutrophic (TLI = 4-5) as external loadings are increased eightfold over current baseline loads, corresponding to the potential land-use intensification in the catchment. This study provides a basis for use of model results in a decision-making process by outlining the environmental consequences of a series of land-use management options, and quantifying nutrient load limits needed to achieve defined trophic state objectives.

10 CFR 431.445 - Determination of small electric motor efficiency.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) General requirements. The average full-load efficiency of each basic model of small electric motor must be... this section, provided, however, that an AEDM may be used to determine the average full-load efficiency of one or more of a manufacturer's basic models only if the average full-load efficiency of at least...

10 CFR 431.445 - Determination of small electric motor efficiency.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) General requirements. The average full-load efficiency of each basic model of small electric motor must be... this section, provided, however, that an AEDM may be used to determine the average full-load efficiency of one or more of a manufacturer's basic models only if the average full-load efficiency of at least...

Comparison of wing-span averaging effects on lift, rolling moment, and bending moment for two span load distributions and for two turbulence representations

NASA Technical Reports Server (NTRS)

Lichtenstein, J. H.

1978-01-01

An analytical method of computing the averaging effect of wing-span size on the loading of a wing induced by random turbulence was adapted for use on a digital electronic computer. The turbulence input was assumed to have a Dryden power spectral density. The computations were made for lift, rolling moment, and bending moment for two span load distributions, rectangular and elliptic. Data are presented to show the wing-span averaging effect for wing-span ratios encompassing current airplane sizes. The rectangular wing-span loading showed a slightly greater averaging effect than did the elliptic loading. In the frequency range most bothersome to airplane passengers, the wing-span averaging effect can reduce the normal lift load, and thus the acceleration, by about 7 percent for a typical medium-sized transport. Some calculations were made to evaluate the effect of using a Von Karman turbulence representation. These results showed that using the Von Karman representation generally resulted in a span averaging effect about 3 percent larger.

Groundwater flux and nutrient loading in the northeast section of Bear Lake, Muskegon County, Michigan, 2015

USGS Publications Warehouse

Totten, Alexander R.; Maurer, Jessica A.; Duris, Joseph W.

2017-11-30

Bear Lake in North Muskegon, Michigan, is listed as part of the Muskegon Lake area of concern as designated by the U.S. Environmental Protection Agency. This area of concern was designated as a result of eutrophication and beneficial use impairments. On the northeast end of Bear Lake, two man-made retention ponds (Willbrandt Pond East and Willbrandt Pond West), formerly used for celery farming, may contribute nutrients to Bear Lake. Willbrandt Ponds (East and West) were previously muck fields that were actively used for celery farming from the early 1900s until 2002. The restoration and reconnection of the Willbrandt Ponds into Bear Lake prompted concerns of groundwater nutrient loading into Bear Lake. Studies done by the State of Michigan and Grand Valley State University revised initial internal phosphorus load estimates and indicated an imbalance in the phosphorus budget in Bear Lake. From June through November 2015, the U.S. Geological Survey (USGS) did an investigative study to quantify the load of nutrients from shallow groundwater around the Willbrandt Ponds in an effort to update the phosphorus budget to Bear Lake. Seven sampling locations were established, including five shallow groundwater wells and two surface-water sites, in the Willbrandt pond study area and Bear Lake. A total of 12 nutrient samples and discrete water-level measurements were collected from each site from June through November 2015. Continuous water-level data were recorded for both surface-water monitoring locations for the entire sampling period.Water-level data indicated that Willbrandt Pond West had the highest average water-level elevation of all sites monitored, which indicated the general direction of flux is from Willbrandt Pond West to Bear Lake. Nutrient and chloride loading from Willbrandt Pond West to Bear Lake was calculated using two distinct methods: Dupuit and direct seepage methods. Shallow groundwater loading calculations were determined by using groundwater levels to first determine a flux of shallow groundwater, then nutrient concentrations to determine a load. It was determined that Willbrandt Pond East and Willbrandt Pond West contributed between 2 to 4 percent of the total annual phosphorus load to Bear Lake by way of shallow groundwater flow. Annual loads calculated for other constituents include orthophosphate (40–100 pounds per year [lb P/yr]), total nitrogen (200–830 lb/yr), chloride (12,700–32,100 lb/yr), and ammonia (130–670 lb N/yr). Study results indicated that mean groundwater and surface-water nutrient concentrations calculated in this study were higher than reported Michigan statewide values. The data collected in this study allow understanding of groundwater nutrient loading into Bear Lake in an effort to help inform future restoration and management decisions.

Cost of illness among patients with diabetic foot ulcer in Turkey

PubMed Central

Oksuz, Ergun; Malhan, Simten; Sonmez, Bilge; Numanoglu Tekin, Rukiye

2016-01-01

AIM To evaluate the annual cost of patients with Wagner grade 3-4-5 diabetic foot ulcer (DFU) from the public payer’s perspective in Turkey. METHODS This study was conducted focused on a time frame of one year from the public payer’s perspective. Cost-of-illness (COI) methodology, which was developed by the World Health Organization, was used in the generation of cost data. By following a clinical path with the COI method, the main total expenses were reached by multiplying the number of uses of each expense item, the percentage of cases that used them and unit costs. Clinical guidelines and real data specific to Turkey were used in the calculation of the direct costs. Monte Carlo Simulation was used in the study as a sensitivity analysis. RESULTS The following were calculated in DFU treatment from the public payer’s perspective: The annual average per patient outpatient costs $579.5 (4.1%), imaging test costs $283.2 (2.0%), laboratory test costs $284.8 (2.0%), annual average per patient cost of intervention, rehabilitation and trainings $2291.7 (16.0%), annual average per patient cost of drugs used $2545.8 (17.8%) and annual average per patient cost of medical materials used in DFU treatment $735.0 (5.1%). The average annual per patient cost for hospital admission is $7357.4 (51.5%). The average per patient complication cost for DFU is $210.3 (1.5%). The average annual per patient cost of DFU treatment in Turkey is $14287.70. As a result of the sensitivity analysis, the standard deviation of the analysis was $5706.60 (n = 5000, mean = $14146.8, 95%CI: $13988.6-$14304.9). CONCLUSION The health expenses per person are $-PPP 1045 in 2014 in Turkey and the average annual per patient cost for DFU is 14-fold of said amount. The total health expense in 2014 in Turkey is $-PPP 80.3 billion and the total DFU cost has a 3% share in the total annual health expenses for Turkey. Hospital costs are the highest component in DFU disease costs. In order to prevent DFU, training of the patients at risk and raising consciousness in patients with diabetes mellitus (DM) will provide benefits in terms of economy. Appropriate and efficient treatment of DM is a health intervention that can prevent complications. PMID:27795820

Storage and residence time of suspended sediment in gravel bars of Difficult Run, VA

NASA Astrophysics Data System (ADS)

George, J.; Benthem, A.; Pizzuto, J. E.; Skalak, K.

2016-12-01

Reducing the export of suspended sediment is an important consideration for restoring water quality to the Chesapeake Bay, but sediment budgets for in-channel landforms are poorly constrained. We quantified fine (< 2 mm) sediment storage and residence times for gravel bars at two reaches along Difficult Run, a 5th order tributary to the Potomac River. Eight gravel bars were mapped in a 150m headwater reach at Miller Heights (bankfull width 11m; total bar volume 114 m3) and 6 gravel bars were mapped in a 160m reach downstream near Leesburg Pike (bankfull width 19m; total bar volume 210 m3). Grain size analyses of surface and subsurface samples from 2 bars at each reach indicate an average suspended sediment content of 55%, suggesting a total volume of suspended sediment stored in the mapped bars to be 178 m3, or 283000 kg, comprising 5% of the average annual suspended sediment load of the two study reaches. Estimates of the annual bedload flux at Miller Heights based on stream gaging records and the Wilcock-Crowe bedload transport equation imply that the bars are entirely reworked at least annually. Scour chains installed in 2 bars at each site (a total of 50 chains) recorded scour and fill events during the winter and spring of 2016. These data indicate that 38% of the total volume of the bars is exchanged per year, for a residence time of 2.6 ± 1.2 years, a value we interpret as the residence time of suspended sediment stored in the bars. These results are supported by mapping of topographic changes derived from structure-from-motion analyses of digital aerial imagery. Storage in alluvial bars therefore represents a significant component of the suspended sediment budget of mid-Atlantic streams.

76 FR 3142 - Notice of Annual Adjustment of the Cap on Average Total Assets That Defines Community Financial...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-19

... FEDERAL HOUSING FINANCE AGENCY [No. 2011-N-01] Notice of Annual Adjustment of the Cap on Average.... ACTION: Notice. SUMMARY: The Federal Housing Finance Agency (FHFA) has adjusted the cap on average total... average total assets below a statutory cap. See 12 U.S.C. 1422(10)(A); 12 CFR 1263.1. The Bank Act was...

Globally Averaged Atmospheric CFC-11 Concentrations: Monthly and Annual Data for the Period 1975-1992 (DB1010)

DOE Data Explorer

Khalil, M. A.K. [Oregon Graduate Institute of Science and Technology Portland, Oregon (USA); Rasmussen, R. A. [Oregon Graduate Institute of Science and Technology Portland, Oregon

1996-01-01

This data set presents globally averaged atmospheric concentrations of chlorofluorocarbon 11, known also as CFC-11 or F-11 (chemical name: trichlorofluoromethane; formula: CCl3F). The monthly global average data are derived from flask air samples collected at eight sites in six locations over the period August 1980-July 1992. The sites are Barrow (Alaska), Cape Meares (Oregon), Cape Kumukahi and Mauna Loa (Hawaii), Cape Matatula (American Samoa), Cape Grim (Tasmania), Palmer Station, and the South Pole (Antarctica). At each collection site, monthly averages were obtained from three flask samples collected every week. In addition to the monthly global averages available for 1980-992, this data set also contains annual global average data for 1975-1985. These annual global averages were derived from January measurements at the South Pole and in the Pacific Northwest of the United States (specifically, Washington state and the Oregon coast).

A case study demonstrating analysis of stormflows, concentrations, and loads of nutrients in highway runoff and swale discharge with the Stochastic Empirical Loading and Dilution Model (SELDM)

USGS Publications Warehouse

Granato, Gregory E.; Jones, Susan C.

2015-01-01

The case study is hypothetical, but was formulated by using actual data from selected monitoring sites in New England. Data representing streamflow and water-quality were collected at U.S. Geological Survey (USGS) streamgage 01208950 Sasco Brook near Southport, CT, which has a drainage area of 7.38 square miles. In this hypothetical case study a 4-lane highway would replace the current 2-lane road and would have a contributing area of 2.2 acres between the topographic basin divides. Concentrations of TN and TP in highway runoff were simulated with data from USGS highway-runoff monitoring station 423027071291301 along State Route 2 in Littleton Massachusetts. Results of a highway-runoff analysis are shown in relation to three hypothetical discharge criteria for TN and two hypothetical discharge criteria for TP. The risks for exceeding TN discharge criteria of 3, 5, and 8 mg/L for highway runoff are 7.4, 0.83, and 0.13 percent of 1,721 runoff events that may occur during a stochastic 30-year simulation. If a grassy swale is used to treat the runoff, the risks for TN exceedances are reduced to 3.2, 0.33 and 0.03 percent, respectively. The risks for exceeding TP discharge criteria of 0.1 and 0.5 mg/L for highway runoff are 49 and 1.2 percent, respectively. If a grassy swale is used to treat the runoff, the risks for TP exceedances are 57 and 0.8 percent, respectively. The risks for the 0.1 mg/L criterion increase because swales can be a source of TP if pavement concentrations are low. The risks for the 0.5 mg/L criterion decrease because the swale is effective for reducing high TP concentrations. Although the results are mixed for storm-event concentrations, the grassy swale effectively reduces annual loads. Annual loads from the swale are, on average, about 49 percent of highway loads for TN and 62 percent of highway loads of TP because the swale reduces high runoff concentrations and stormflow volumes. Analysis of upstream and downstream concentrations indicates that runoff from the site of interest does not have a substantial effect on instream stormflow concentrations in this example simulation.

Modeling nutrient release in the Tai Lake basin of China: source identification and policy implications.

PubMed

Liu, Beibei; Liu, Heng; Zhang, Bing; Bi, Jun

2013-03-01

Because nutrient enrichment has become increasingly severe in the Tai Lake Basin of China, identifying sources and loads is crucial for watershed nutrient management. This paper develops an empirical framework to estimate nutrient release from five major sectors, which requires fewer input parameters and produces acceptable accuracy. Sectors included are industrial manufacturing, livestock breeding (industrial and family scale), crop agriculture, household consumption (urban and rural), and atmospheric deposition. Results show that in the basin (only the five sectors above), total nutrient loads of nitrogen (N) and phosphorus (P) into aquatic systems in 2008 were 33043.2 tons N a(-1) and 5254.4 tons P a(-1), and annual area-specific nutrient loads were 1.94 tons N km(-2) and 0.31 tons P km(-2). Household consumption was the major sector having the greatest impact (46 % in N load, 47 % in P load), whereas atmospheric deposition (18 %) and crop agriculture (15 %) sectors represented other significant proportions of N load. The load estimates also indicate that 32 % of total P came from the livestock breeding sector, making it the second largest phosphorus contributor. According to the nutrient pollution sectors, six best management practices are selected for cost-effectiveness analysis, and feasible options are recommended. Overall, biogas digester construction on industrial-scale farms is proven the most cost-effective, whereas the building of rural decentralized facilities is the best alternative under extreme financial constraint. However, the reduction potential, average monetary cost, and other factors such as risk tolerance of policy makers should all be considered in the actual decision-making process.

Sediment transport and evaluation of sediment surrogate ratings in the Kootenai River near Bonners Ferry, Idaho, Water Years 2011–14

USGS Publications Warehouse

Wood, Molly S.; Fosness, Ryan L.; Etheridge, Alexandra B.

2015-12-14

Acoustic surrogate ratings were developed between backscatter data collected using acoustic Doppler velocity meters (ADVMs) and results of suspended-sediment samples. Ratings were successfully fit to various sediment size classes (total, fines, and sands) using ADVMs of different frequencies (1.5 and 3 megahertz). Surrogate ratings also were developed using variations of streamflow and seasonal explanatory variables. The streamflow surrogate ratings produced average annual sediment load estimates that were 8–32 percent higher, depending on site and sediment type, than estimates produced using the acoustic surrogate ratings. The streamflow surrogate ratings tended to overestimate suspended-sediment concentrations and loads during periods of elevated releases from Libby Dam as well as on the falling limb of the streamflow hydrograph. Estimates from the acoustic surrogate ratings more closely matched suspended-sediment sample results than did estimates from the streamflow surrogate ratings during these periods as well as for rating validation samples collected in water year 2014. Acoustic surrogate technologies are an effective means to obtain continuous, accurate estimates of suspended-sediment concentrations and loads for general monitoring and sediment-transport modeling. In the Kootenai River, continued operation of the acoustic surrogate sites and use of the acoustic surrogate ratings to calculate continuous suspended-sediment concentrations and loads will allow for tracking changes in sediment transport over time.

Systematic review of the relationship of Helicobacter pylori infection with geographical latitude, average annual temperature and average daily sunshine.

PubMed

Lu, Chao; Yu, Ye; Li, Lan; Yu, Chaohui; Xu, Ping

2018-04-17

Helicobacter pylori (H. pylori) infection is a worldwide threat to human health with high prevalence. In this study, we analyzed the relationship between latitude, average annual temperature, average daily sunshine time and H. pylori infection. The PubMed, ClinicalTrials.gov , EBSCO and Web of Science databases were searched to identify studies reporting H. pylori infection. Latitude 30° was the cut-off level for low and mid-latitude areas. We obtained information for latitude, average annual temperature, average daily sunshine, and Human Development Index (HDI) from reports of studies of the relationships with H. pylori infection. Of the 51 studies included, there was significant difference in H. pylori infection between the low- and mid-latitude areas (P = 0.05). There was no significant difference in the prevalence of H. pylori infection in each 15°-latitude zone analyzed (P = 0.061). Subgroup analysis revealed the highest and lowest H. pylori infection rates in the developing regions at > 30° latitude subgroup and the developed regions at < 30° latitude subgroup, respectively (P < 0.001). Multivariate analysis showed that average annual temperature, average daily sunshine time and HDI were significantly correlated with H. pylori infection (P = 0.009, P < 0.001, P < 0.001), while there was no correlation between H. pylori infection and latitude. Our analysis showed that higher average annual temperature was associated with lower H. pylori infection rates, while average daily sunshine time correlated positively with H. pylori infection. HDI was also found to be a significant factor, with higher HDI associated with lower infection rates. These findings provide evidence that can be used to devise strategies for the prevention and control of H. pylori.

Military Free Fall Scheduling And Manifest Optimization Model

DTIC Science & Technology

2016-12-01

engines running waiting for the next student load. The annual blade hour cost, which consists of fuel, maintenance, and personnel, is $5.6M for FY-16...tarmac with engines running waiting for the next student load (J. Enke, personal communication, 2016). The annual blade hour cost, which consists of...33 Scenario 2 Nonstandard Run #1 C-27 Two Passes per Lift .......................34 Table 9. xii THIS PAGE INTENTIONALLY LEFT BLANK xiii

Estimating 1970-99 average annual groundwater recharge in Wisconsin using streamflow data

USGS Publications Warehouse

Gebert, Warren A.; Walker, John F.; Kennedy, James L.

2011-01-01

Average annual recharge in Wisconsin for the period 1970-99 was estimated using streamflow data from U.S. Geological Survey continuous-record streamflow-gaging stations and partial-record sites. Partial-record sites have discharge measurements collected during low-flow conditions. The average annual base flow of a stream divided by the drainage area is a good approximation of the recharge rate; therefore, once average annual base flow is determined recharge can be calculated. Estimates of recharge for nearly 72 percent of the surface area of the State are provided. The results illustrate substantial spatial variability of recharge across the State, ranging from less than 1 inch to more than 12 inches per year. The average basin size for partial-record sites (50 square miles) was less than the average basin size for the gaging stations (305 square miles). Including results for smaller basins reveals a spatial variability that otherwise would be smoothed out using only estimates for larger basins. An error analysis indicates that the techniques used provide base flow estimates with standard errors ranging from 5.4 to 14 percent.

Sediment Flux of Particulate Organic Phosphorus in the Open Black Sea

NASA Astrophysics Data System (ADS)

Parkhomenko, A. V.; Kukushkin, A. S.

2018-03-01

The interannual variation of the monthly average (weighted average) concentrations of particulate organic phosphorus (PPOM) in the photosynthetic layer, oxycline, redox zone, and H2S zone in the open Black Sea is estimated based on long-term observation data. The suspension sedimentation rates from the studied layers are assessed using model calculations and published data. The annual variation of PPOM sediment fluxes from the photosynthetic layer, oxycline, redox zone, and upper H2S zone to the anaerobic zone of the sea and the correspondingly annual average values are estimated for the first time. A regular decrease in the PPOM annual average flux with depth in the upper active layer is demonstrated. A correlation between the annual average values of PPOM sediment flux from the photosynthetic layer and ascending phosphate flux to this layer is shown, which suggests their balance in the open sea. The results are discussed in terms of the phosphorus biogeochemical cycle and the concept of new and regenerative primary production in the open Black Sea.

An estimation of Canadian population exposure to cosmic rays.

PubMed

Chen, Jing; Timmins, Rachel; Verdecchia, Kyle; Sato, Tatsuhiko

2009-08-01

The worldwide average exposure to cosmic rays contributes to about 16% of the annual effective dose from natural radiation sources. At ground level, doses from cosmic ray exposure depend strongly on altitude, and weakly on geographical location and solar activity. With the analytical model PARMA developed by the Japan Atomic Energy Agency, annual effective doses due to cosmic ray exposure at ground level were calculated for more than 1,500 communities across Canada which cover more than 85% of the Canadian population. The annual effective doses from cosmic ray exposure in the year 2000 during solar maximum ranged from 0.27 to 0.72 mSv with the population-weighted national average of 0.30 mSv. For the year 2006 during solar minimum, the doses varied between 0.30 and 0.84 mSv, and the population-weighted national average was 0.33 mSv. Averaged over solar activity, the Canadian population-weighted average annual effective dose due to cosmic ray exposure at ground level is estimated to be 0.31 mSv.

Pesticides, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls in transport in two Atlantic coastal plain tributaries and loadings to Chesapeake Bay

USGS Publications Warehouse

Foster, G.D.; Miller, C.V.; Huff, T.B.; Roberts, E.

2003-01-01

Concentrations of current-use pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine (OC) insecticides were determined above the reach of tide in the Chesterville Branch and Nanticoke River on the eastern shore of Chesapeake Bay during base-flow and storm-flow hydrologic regimes to evaluate mass transport to Chesapeake Bay. The two rivers monitored showed relatively high concentrations of atrazine, simazine, alachlor, and metolachlor in comparison to previously investigated western shore tributaries, and reflected the predominant agricultural land use in the eastern shore watersheds. The four current use pesticides showed the greatest seasonal contribution to annual loadings to tidal waters of Chesapeake Bay from the two rivers, and the relative order of annual loadings for the other contaminant classes was PAHs > PCBs > OC insecticides. Annual loadings normalized to the landscape areas of selected Chesapeake Bay watersheds showed correlations to identifiable source areas, with the highest pesticide yields (g/km2/yr) occurring in eastern shore agricultural landscapes, and the highest PAH yields derived from urban regions.

Stress Models of the Annual Hydrospheric, Atmospheric, Thermal, and Tidal Loading Cycles on California Faults: Perturbation of Background Stress and Changes in Seismicity

NASA Astrophysics Data System (ADS)

Johnson, Christopher W.; Fu, Yuning; Bürgmann, Roland

2017-12-01

Stresses in the lithosphere arise from multiple natural loading sources that include both surface and body forces. The largest surface loads include near-surface water storage, snow and ice, atmosphere pressure, ocean loading, and temperature changes. The solid Earth also deforms from celestial body interactions and variations in Earth's rotation. We model the seasonal stress changes in California from 2006 through 2014 for seven different loading sources with annual periods to produce an aggregate stressing history for faults in the study area. Our modeling shows that the annual water loading, atmosphere, temperature, and Earth pole tides are the largest loading sources and should each be evaluated to fully describe seasonal stress changes. In California we find that the hydrological loads are the largest source of seasonal stresses. We explore the seasonal stresses with respect to the background principal stress orientation constrained with regional focal mechanisms and analyze the modulation of seismicity. Our results do not suggest a resolvable seasonal variation for the ambient stress orientation in the shallow crust. When projecting the seasonal stresses into the background stress orientation we find that the timing of microseismicity modestly increases from an 8 kPa seasonal mean-normal-stress perturbation. The results suggest that faults in California are optimally oriented with the background stress field and respond to subsurface pressure changes, possibly due to processes we have not considered in this study. At any time a population of faults are near failure as evident from earthquakes triggered by these slight seasonal stress perturbations.

Effects of May through July 2015 storm events on suspended sediment loads, sediment trapping efficiency, and storage capacity of John Redmond Reservoir, east-central Kansas

USGS Publications Warehouse

Foster, Guy M.

2016-06-20

The U.S. Geological Survey, in cooperation with the Kansas Water Office, computed the suspended-sediment inflows and retention in John Redmond Reservoir during May through July 2015. Computations relied upon previously published turbidity-suspended sediment relations at water-quality monitoring sites located upstream and downstream from the reservoir. During the 3-month period, approximately 872,000 tons of sediment entered the reservoir, and 57,000 tons were released through the reservoir outlet. The average monthly trapping efficiency during this period was 93 percent, and monthly averages ranged from 83 to 97 percent. During the study period, an estimated 980 acre-feet of storage was lost, over 2.4 times the design annual sedimentation rate of the reservoir. Storm inflows during the 3-month analysis period reduced reservoir storage in the conservation pool approximately 1.6 percent. This indicates that large inflows, coupled with minimal releases, can have substantial effects on reservoir storage and lifespan.

10 CFR 431.12 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... method or AEDM means, with respect to an electric motor, a method of calculating the total power loss and average full load efficiency. Average full load efficiency means the arithmetic mean of the full load efficiencies of a population of electric motors of duplicate design, where the full load efficiency of each...

The quasi-biennial vertical oscillations at global GPS stations: identification by ensemble empirical mode decomposition.

PubMed

Pan, Yuanjin; Shen, Wen-Bin; Ding, Hao; Hwang, Cheinway; Li, Jin; Zhang, Tengxu

2015-10-14

Modeling nonlinear vertical components of a GPS time series is critical to separating sources contributing to mass displacements. Improved vertical precision in GPS positioning at stations for velocity fields is key to resolving the mechanism of certain geophysical phenomena. In this paper, we use ensemble empirical mode decomposition (EEMD) to analyze the daily GPS time series at 89 continuous GPS stations, spanning from 2002 to 2013. EEMD decomposes a GPS time series into different intrinsic mode functions (IMFs), which are used to identify different kinds of signals and secular terms. Our study suggests that the GPS records contain not only the well-known signals (such as semi-annual and annual signals) but also the seldom-noted quasi-biennial oscillations (QBS). The quasi-biennial signals are explained by modeled loadings of atmosphere, non-tidal and hydrology that deform the surface around the GPS stations. In addition, the loadings derived from GRACE gravity changes are also consistent with the quasi-biennial deformations derived from the GPS observations. By removing the modeled components, the weighted root-mean-square (WRMS) variation of the GPS time series is reduced by 7.1% to 42.3%, and especially, after removing the seasonal and QBO signals, the average improvement percentages for seasonal and QBO signals are 25.6% and 7.5%, respectively, suggesting that it is significant to consider the QBS signals in the GPS records to improve the observed vertical deformations.

The Quasi-Biennial Vertical Oscillations at Global GPS Stations: Identification by Ensemble Empirical Mode Decomposition

PubMed Central

Pan, Yuanjin; Shen, Wen-Bin; Ding, Hao; Hwang, Cheinway; Li, Jin; Zhang, Tengxu

2015-01-01

Modeling nonlinear vertical components of a GPS time series is critical to separating sources contributing to mass displacements. Improved vertical precision in GPS positioning at stations for velocity fields is key to resolving the mechanism of certain geophysical phenomena. In this paper, we use ensemble empirical mode decomposition (EEMD) to analyze the daily GPS time series at 89 continuous GPS stations, spanning from 2002 to 2013. EEMD decomposes a GPS time series into different intrinsic mode functions (IMFs), which are used to identify different kinds of signals and secular terms. Our study suggests that the GPS records contain not only the well-known signals (such as semi-annual and annual signals) but also the seldom-noted quasi-biennial oscillations (QBS). The quasi-biennial signals are explained by modeled loadings of atmosphere, non-tidal and hydrology that deform the surface around the GPS stations. In addition, the loadings derived from GRACE gravity changes are also consistent with the quasi-biennial deformations derived from the GPS observations. By removing the modeled components, the weighted root-mean-square (WRMS) variation of the GPS time series is reduced by 7.1% to 42.3%, and especially, after removing the seasonal and QBO signals, the average improvement percentages for seasonal and QBO signals are 25.6% and 7.5%, respectively, suggesting that it is significant to consider the QBS signals in the GPS records to improve the observed vertical deformations. PMID:26473882

Annual and Semi-Annual Temperature Oscillations in the Upper Mesosphere

NASA Technical Reports Server (NTRS)

Niciejewski, R. J.; Killeen, T. L.

1995-01-01

Fourier transform spectrometer observations of the mesosphere have been performed at the University of Michigan (latitude: 42.5 N) on a long term basis. A database of near infrared Meinel hydroxyl spectra has been accumulated from which rotational temperatures have been determined. Harmonic analysis of one-day averaged temperatures for the period 1992.0 to 1994.5 has shown a distinct annual and semi-annual variation. Subsequent fitting of a five term periodic function characterizing the annual and semi-annual temperature oscillations to the daily averaged temperatures was performed. The resultant mean temperature and the amplitudes and phases of the annual and semi-annual variations are shown to coincide with an emission height slightly above 85 km which is consistent with the mean rocket derived altitude for peak nocturnal hydroxyl emission.

Discharge, suspended sediment, bedload, and water quality in Clear Creek, western Nevada, water years 2010-12

USGS Publications Warehouse

Huntington, Jena M.; Savard, Charles S.

2015-09-30

During this study, total annual sediment loads ranged from 355 tons per year in 2010 to 1,768 tons per year in 2011 and were significantly lower than the previous study (water years 2004–07). Bedload represented between 29 and 38 percent of total sediment load in water years 2010–12, and between 72 and 90 percent of the total sediment load in water years 2004–07, which indicates a decrease in bedload between study periods. Annual suspended-sediment loads in water years 2010–12 indicated no significant change from water years 2004–07. Mean daily discharge was significantly lower in water years 2010–12 than in waters years 2004–07 and may be the reason for the decrease in bedload that resulted in a lower total sediment load.

Variations of Runoff and Sediment Load in the Middle and Lower Reaches of the Yangtze River, China (1950-2013)

PubMed Central

Li, Na; Wang, Lachun; Zeng, Chunfen; Wang, Dong; Liu, Dengfeng; Wu, Xutong

2016-01-01

On the basis of monthly runoff series obtained in 1950–2013 and annual sediment load measured in 1956–-2013 at five key hydrological stations in the middle and lower reaches of the Yangtze River basin, this study used the Mann-Kendall methods to identify trend and abrupt changes of runoff and sediment load in relation to human activities. The results were as follows: (1) The annual and flood season runoffs showed significant decreasing trends at Yichang station, and showed slight downward trends at Hankou and Datong stations, while the abrupt changes of dry season runoff at Yichang, Hankou and Datong stations occurred in about 2007 and the change points were followed by significant increasing trends. The construction of the Three Gorges Dam, which began to operate in 2003, influenced the variations of runoff in the mainstream of Yangtze River, but the effect weakened with the distance along the downstream direction from TGD. (2) Since the 1990s, annual sediment loads at Yichang, Hankou, and Datong stations have been decreasing significantly, and after 2002, the annual sediment load at Yichang dropped below that of Hankou and Datong. The dams and deforestation/forestation contributed to the significant decreasing trend of the sediment load. In addition, the Three Gorges Dam aggravated the downward trend and caused the erosion of the riverbed and riverbanks in the middle and lower reaches. (3) The runoff and sediment load flowing from Dongting Lake into the mainstream of the Yangtze River showed significant decreasing trends at Chenglingji station after 1970s, and in contrast, slight increase in the sediment flow from Poyang Lake to the mainstream of the Yangtze River at Hukou station were detected over the post-TGD period (2003–2013). The result of the study will be an important foundation for watershed sustainable development of the Yangtze River under the human activities. PMID:27479591

Variations of Runoff and Sediment Load in the Middle and Lower Reaches of the Yangtze River, China (1950-2013).

PubMed

Li, Na; Wang, Lachun; Zeng, Chunfen; Wang, Dong; Liu, Dengfeng; Wu, Xutong

2016-01-01

On the basis of monthly runoff series obtained in 1950-2013 and annual sediment load measured in 1956--2013 at five key hydrological stations in the middle and lower reaches of the Yangtze River basin, this study used the Mann-Kendall methods to identify trend and abrupt changes of runoff and sediment load in relation to human activities. The results were as follows: (1) The annual and flood season runoffs showed significant decreasing trends at Yichang station, and showed slight downward trends at Hankou and Datong stations, while the abrupt changes of dry season runoff at Yichang, Hankou and Datong stations occurred in about 2007 and the change points were followed by significant increasing trends. The construction of the Three Gorges Dam, which began to operate in 2003, influenced the variations of runoff in the mainstream of Yangtze River, but the effect weakened with the distance along the downstream direction from TGD. (2) Since the 1990s, annual sediment loads at Yichang, Hankou, and Datong stations have been decreasing significantly, and after 2002, the annual sediment load at Yichang dropped below that of Hankou and Datong. The dams and deforestation/forestation contributed to the significant decreasing trend of the sediment load. In addition, the Three Gorges Dam aggravated the downward trend and caused the erosion of the riverbed and riverbanks in the middle and lower reaches. (3) The runoff and sediment load flowing from Dongting Lake into the mainstream of the Yangtze River showed significant decreasing trends at Chenglingji station after 1970s, and in contrast, slight increase in the sediment flow from Poyang Lake to the mainstream of the Yangtze River at Hukou station were detected over the post-TGD period (2003-2013). The result of the study will be an important foundation for watershed sustainable development of the Yangtze River under the human activities.

Effects of crop load on distribution and utilization of 13C and 15N and fruit quality for dwarf apple trees.

PubMed

Ding, Ning; Chen, Qian; Zhu, Zhanling; Peng, Ling; Ge, Shunfeng; Jiang, Yuanmao

2017-10-26

In order to define the effects of fruit crop load on the distribution and utilization of carbon and nitrogen in dwarf apple trees, we conducted three crop load levels (High-crop load, 6 fruits per trunk cross-sectional area (cm 2 , TCA)), Medium-crop load (4 fruits cm -2 TCA), Low-crop load (2 fruits cm -2 TCA)) in 2014 and 2015. The results indicated that the 15 N derived from fertilizer (Ndff) values of fruits decreased with the reduction of crop load, but the Ndff values of annual branches, leaves and roots increased. The plant 15 N-urea utilization rates on Medium and Low-crop load were 1.12-1.35 times higher than the High-crop load. With the reduction of crop load, the distribution rate of 13 C and 15 N in fruits was gradually reduced, but in contrast, the distribution of 13 C and 15 N gradually increased in annual branches, leaves and roots. Compared with High-crop load, the Medium and Low-crop load significantly improved fruit quality p < 0.05. Hence, controlling fruit load effectively regulated the distribution of carbon and nitrogen in plants, improved the nitrogen utilization rate and fruit quality. The appropriate crop load level for mature M.26 interstocks apple orchards was deemed to be 4.0 fruits cm -2 TCA.

Evaluation of the solar conditions for the acquisitions of energy from renewable sources on the base of Sosnowiec city (Poland)

NASA Astrophysics Data System (ADS)

Sarapata, Sonia

2014-09-01

The country's energy security risk, as well as a desire to protect the environment from the pollution and degradation which are the results of conventional fuels acquisition - these was a motivation for intensive researches on the use of renewable energy sources in eco - innovative installations. Solar radiation is one of the self - renewable energy sources which can be used both as a source of electricity and heat. The area of research is Sosnowiec city located in the south of Poland in the eastern part of Silesia voivodeship. The solar radiation data covering the years 2003 to 2013 was used. The intra - annual variability of daily averaged solar radiation hesitated in a wide range from 0.6 kWh/m2 (December) to 5.2 kWh/m2 (June). Day duration varies on average from 10 hours in January, November and December to 17 hours in May, June and July. Day occupies 56% of the 8767 hours in year. On average the largest amount of energy reached the analyzed area in July: 157 kWh/m2 (15% of the annual average), while the smallest in December: 18 kWh/m2 (less than 2% of the annual average). The 75% of the average annual total of energy falls on the period from 1st March to 31th August (spring - summer). The range of the annual solar radiation was determined by the minimum of 980 kWh/m2 and the maximum of 1094 kWh/m2. In Sosnowiec the average annual irradiation total on the horizontal surface amounts to 1052 kWh/m2 (2003 - 2013)

Assessing Chemical Retention Process Controls in Ponds

NASA Astrophysics Data System (ADS)

Torgersen, T.; Branco, B.; John, B.

2002-05-01

Small ponds are a ubiquitous component of the landscape and have earned a reputation as effective chemical retention devices. The most common characterization of pond chemical retention is the retention coefficient, Ri= ([Ci]inflow-[Ci] outflow)/[Ci]inflow. However, this parameter varies widely in one pond with time and among ponds. We have re-evaluated literature reported (Borden et al., 1998) monthly average retention coefficients for two ponds in North Carolina. Employing a simple first order model that includes water residence time, the first order process responsible for species removal have been separated from the water residence time over which it acts. Assuming the rate constant for species removal is constant within the pond (arguable at least), the annual average rate constant for species removal is generated. Using the annual mean rate constant for species removal and monthly water residence times results in a significantly enhanced predictive capability for Davis Pond during most months of the year. Predictive ability remains poor in Davis Pond during winter/unstratified periods when internal loading of P and N results in low to negative chemical retention. Predictive ability for Piedmont Pond (which has numerous negative chemical retention periods) is improved but not to the same extent as Davis Pond. In Davis Pond, the rate constant for sediment removal (each month) is faster than the rate constant for water and explains the good predictability for sediment retention. However, the removal rate constant for P and N is slower than the removal rate constant for sediment (longer water column residence time for P,N than for sediment). Thus sedimentation is not an overall control on nutrient retention. Additionally, the removal rate constant for P is slower than for TOC (TOC is not the dominate removal process for P) and N is removed slower than P (different in pond controls). For Piedmont Pond, sediment removal rate constants are slower than the removal rate constant for water indicating significant sediment resuspension episodes. It appears that these sediment resuspension events are aperiodic and control the loading and the chemical retention capability of Piedmont Pond for N,P,TOC. These calculated rate constants reflect the differing internal loading processes for each component and suggest means and mechanisms for the use of ponds in water quality management.

Impact of repeated ivermectin treatments against onchocerciasis on the transmission of loiasis: an entomologic evaluation in central Cameroon.

PubMed

Kouam, Marc K; Tchatchueng-Mbougua, Jules B; Demanou, Maurice; Boussinesq, Michel; Pion, Sébastien D S; Kamgno, Joseph

2013-09-27

Annual community-directed treatment with ivermectin (CDTI) have been carried out since 1999 in the Lekie division (central region of Cameroon where most cases of Loa-related post ivermectin severe adverse events were reported) as part of the joined activities of the African Programme for Onchocerciasis Control (APOC) and Mectizan® Donation Program (MDP). As large-scale administration of ivermetine was demonstrated to be an efficient means to control loiasis transmission, it was hypothesized that CDTI would have lowered or halted the transmission of Loa loa in the Lekie division after 13 years of annual drug administration, indicating a possible reduction in the occurrence of Loa-related post-ivermectin severe adverse events. A 4-month entomologic study was carried out from March to June 2012 in the Lekie division to evaluate the impact of 13 years of CDTI on the transmission of L. loa whose baseline data were recorded in 1999-2000. There was a significant reduction in the infection rate for Chrysops silacea and C. dimidiata from 6.8 and 9% in 1999-2000 to 3 and 3.6% in 2012, respectively. The differences in the infective rate (IR) (percentage of flies harboring head L3 larvae), potential infective rate (PIR) (percentage of flies bearing L3 larvae), mean head L3 larvae load (MHL3) (average L3 per infective fly) and mean fly L3 larvae load (MFL3) (average L3 per potentially infective fly) for both C. silacea and C. dimidiata were not significantly different between the two investigation periods. The biting density (BD) was almost three-fold higher in 2012 for C. silacea but not for C. dimidiata. The transmission potential (TP) which is a function of the BD, was higher in the present study than in the baseline investigation for each species. The infection rate remaining high, the high TP and the stability observed in the IR, PIR, MHL3 and MFL3 after 13 years of CDTI suggest that transmission of L. loa is still active. This is an indication that the risk of occurrence of severe adverse events such as fatal encephalopathies is still present, especially for heavily microfilaria-loaded people taken ivermectin for the first time.

Impact of repeated ivermectin treatments against onchocerciasis on the transmission of loiasis: an entomologic evaluation in central Cameroon

PubMed Central

2013-01-01

Background Annual community-directed treatment with ivermectin (CDTI) have been carried out since 1999 in the Lekie division (central region of Cameroon where most cases of Loa-related post ivermectin severe adverse events were reported) as part of the joined activities of the African Programme for Onchocerciasis Control (APOC) and Mectizan® Donation Program (MDP). As large-scale administration of ivermetine was demonstrated to be an efficient means to control loiasis transmission, it was hypothesized that CDTI would have lowered or halted the transmission of Loa loa in the Lekie division after 13 years of annual drug administration, indicating a possible reduction in the occurrence of Loa-related post-ivermectin severe adverse events. Methods A 4-month entomologic study was carried out from March to June 2012 in the Lekie division to evaluate the impact of 13 years of CDTI on the transmission of L. loa whose baseline data were recorded in 1999–2000. Results There was a significant reduction in the infection rate for Chrysops silacea and C. dimidiata from 6.8 and 9% in 1999–2000 to 3 and 3.6% in 2012, respectively. The differences in the infective rate (IR) (percentage of flies harboring head L3 larvae), potential infective rate (PIR) (percentage of flies bearing L3 larvae), mean head L3 larvae load (MHL3) (average L3 per infective fly) and mean fly L3 larvae load (MFL3) (average L3 per potentially infective fly) for both C. silacea and C. dimidiata were not significantly different between the two investigation periods. The biting density (BD) was almost three-fold higher in 2012 for C. silacea but not for C. dimidiata. The transmission potential (TP) which is a function of the BD, was higher in the present study than in the baseline investigation for each species. Conclusion The infection rate remaining high, the high TP and the stability observed in the IR, PIR, MHL3 and MFL3 after 13 years of CDTI suggest that transmission of L. loa is still active. This is an indication that the risk of occurrence of severe adverse events such as fatal encephalopathies is still present, especially for heavily microfilaria-loaded people taken ivermectin for the first time. PMID:24289520

20 CFR 226.63 - Determining monthly compensation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... obtained by dividing the average annual wage for the indexing year by the average annual wage for the year... wage for 1951 is used. (2) Indexing year defined. The indexing year is the second year before the year...

20 CFR 226.63 - Determining monthly compensation.

Code of Federal Regulations, 2014 CFR

2014-04-01

... obtained by dividing the average annual wage for the indexing year by the average annual wage for the year... wage for 1951 is used. (2) Indexing year defined. The indexing year is the second year before the year...

20 CFR 226.63 - Determining monthly compensation.

Code of Federal Regulations, 2013 CFR

2013-04-01

... obtained by dividing the average annual wage for the indexing year by the average annual wage for the year... wage for 1951 is used. (2) Indexing year defined. The indexing year is the second year before the year...

20 CFR 226.63 - Determining monthly compensation.

Code of Federal Regulations, 2011 CFR

2011-04-01

... obtained by dividing the average annual wage for the indexing year by the average annual wage for the year... wage for 1951 is used. (2) Indexing year defined. The indexing year is the second year before the year...

20 CFR 226.63 - Determining monthly compensation.

Code of Federal Regulations, 2012 CFR

2012-04-01

... obtained by dividing the average annual wage for the indexing year by the average annual wage for the year... wage for 1951 is used. (2) Indexing year defined. The indexing year is the second year before the year...

Schedule of average annual equipment ownership expense

DOT National Transportation Integrated Search

2003-03-06

The "Schedule of Average Annual Equipment Ownership Expense" is designed for use on Force Account bills of Contractors performing work for the Illinois Department of Transportation and local government agencies who choose to adopt these rates. This s...

Stationarity and Inequality from the Mississippi to the Kissimmee: Climatic Control of Temporal Patterns in Catchment Discharge and Solute Export

NASA Astrophysics Data System (ADS)

Jawitz, J. W.

2011-12-01

What are the relative contributions of climatic variability, land management, and local geomorphology in determining the temporal dynamics of streamflow and the export of solutes from watersheds to receiving water bodies? A simple analytical framework is introduced for characterizing the temporal inequality of stream discharge and solute export from catchments using Lorenz diagrams and the associated Gini coefficient. These descriptors are used to illustrate a broad range of observed flow variability with a synthesis of multi-decadal flow data from 22 rivers in Florida. The analytical framework is extended to comprehensively link variability in flows and loads to climatically-driven inputs in terms of these inequality-based metrics. Further, based on a synthesis of data from the basins of the Baltic Sea, the Mississippi River, the Kissimmee River and other tributaries to Lake Okeechobee, FL, it is shown that inter-annual variations in exported loads for geogenic constituents, and for total N and total P, are dominantly controlled by discharge. Emergence of this consistent pattern across diverse managed catchments is attributed to the anthropogenic legacy of accumulated nutrient sources generating memory, similar to ubiquitously present sources for geogenic constituents. Multi-decadal phosphorus load data from 4 of the primary tributaries to Lake Okeechobee and sodium and nitrate load data from 9 of the Hubbard Brook, NH long-term study site catchments are used to examine the relation between inequality of climatic inputs, river flows and catchment loads. The intra-annual loads to Lake Okeechobee are shown to be highly unequal, such that 90% of annual load is delivered in as little as 15% of the time. Analytic expressions are developed for measures of inequality in terms of parameters of the lognormal distribution under general conditions that include intermittency. In cases where climatic variability is high compared to that of concentrations (chemostatic conditions), such as for P in the Lake Okeechobee basin and Na in Hubbard Brook, the temporal inequality of rainfall and flow are strong surrogates for load inequality. However, in cases where variability of concentrations is high compared to that of flows (chemodynamic conditions), such as for nitrate in the Hubbard Brook catchments, load inequality is greater than rainfall or flow inequality. The measured degree of correspondence between climatic, flow, and load inequality for these data sets are shown to be well described using the general inequality framework introduced here. Important implications are that (1) variations in hydro-climatic or anthropogenic forcing can be used to robustly predict inter-annual variations in flows and loads, (2) water quality problems in receiving inland and coastal waters may persist until the accumulated storages of nutrients have been substantially depleted, and (3) remedial measures designed to intercept or capture exported flows and loads must be designed with consideration of the intra-annual inequality.

The Great Basin Canada goose in southcentral Washington: A 40-year nesting history

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fitzner, R.E.; Rickard, W.H.; Eberhardt, L.E.

1991-04-01

Overall, the nesting population of Great Basin Canada geese (Branta canadensis moffitti) on the Hanford Site in southcentral Washington State is doing well and appears to be increasing. The average annual total nests for the period 1981 through 1990 was 215 nests, which is slightly above the average reported for the period 1950 through 1970. The nesting population has shifted its nucleus from upriver islands (1--10) to the lower river islands (11--20) with over 70% of the present-day nesting occurring on Islands 17, 18, 19, 20. The annual percent-successful nests from 1981 through 1990 was 80%. This is above themore » 71% reported for 1950 to 1970, but is below the 82% reported for 1971 to 1980. Average annual clutch size for 1981 to 1990 was 6.05, which is above the 1971-to-1980 average of 5.6 and the 1950-to-70 average of 5.5. Next desertions for 1981 to 1990 averaged 8%. This rate is well below the 14% reported for 1950 to 1970. Predators were responsible for an annual predation rate of 9% from 1981 to 1990. This is below the 1950-to-1970 annual average predation rate of 14%. Flooding losses to nests were low during the 1980s, except for 1989 and 1990 when 6% and 9% of the total nests, respectively, were destroyed by flooding. 9 refs., 4 figs., 1 tab.« less

40 CFR 439.12 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2011 CFR

2011-07-01

... percent reduction in the long-term average daily BOD5 load of the raw (untreated) process wastewater, multiplied by a variability factor of 3.0. (1) The long-term average daily BOD5 load of the raw process... concentration value reflecting a reduction in the long-term average daily COD load in the raw (untreated...

40 CFR 439.12 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2010 CFR

2010-07-01

... percent reduction in the long-term average daily BOD5 load of the raw (untreated) process wastewater, multiplied by a variability factor of 3.0. (1) The long-term average daily BOD5 load of the raw process... concentration value reflecting a reduction in the long-term average daily COD load in the raw (untreated...

An economic evaluation of intervention strategies for Porcine Epidemic Diarrhea (PED).

PubMed

Weng, Longfeng; Weersink, Alfons; Poljak, Zvonimir; de Lange, Kees; von Massow, Mike

2016-11-01

The economic losses of Porcine Epidemic Diarrhea (PED) and the net benefits of strategies to control the virus are calculated for individual farrow-to-finish herds. A production simulation model that estimates the number of pigs by population cohorts on a weekly basis for a farrow-to-finish farm depending on production parameters is simulated under normal operating conditions and then with an outbreak of PED. The estimated annual costs of a PED outbreak with the closure of the breeding herd as the only intervention is approximately $300,000 for a 700-sow farrow-to-finishing herd. The net returns per sow (hog) fall from $255 ($11.54) to a loss of $174 ($10.68). These losses can be significantly reduced with any of the 16 intervention strategies considered in this study. The most profitable strategy involving front loading of gilts with average feedback of infected material to improve herd immunity, intensive biosecurity protocols and no vaccination costs $27,000 to implement but reduces losses by 10 times this amount. Even the implementation of the least comprehensive strategy, which involves back-loading gilts after the herd reopens and an average feedback practice at a cost of $1000 reduces the losses caused by a PED outbreak by $130,000. Front-loading gilts in combination with herd closure is more cost-effective than back-loading. Despite the extra spending on intensive biosecurity protocols, the overall loss reductions achieved by the intensive biosecurity effort can be significant. Vaccination is the least cost-effective of the intervention practices considered. Even with significant increases in cost or effectiveness in the practices, intervention is justified across all strategies. The spreadsheet model of a farrow-finish hog farm developed in this study can be used to examine changes to the production parameters or to consider other swine disease outbreaks. Copyright © 2016 Elsevier B.V. All rights reserved.

Benzo[a]pyrene in urban environments of eastern Moscow: pollution levels and critical loads

NASA Astrophysics Data System (ADS)

Kasimov, Nikolay S.; Kosheleva, Natalia E.; Nikiforova, Elena M.; Vlasov, Dmitry V.

2017-02-01

Polycyclic aromatic hydrocarbons (PAHs), particularly benzo[a]pyrene (BaP), are toxic compounds emitted from various anthropogenic sources. Understanding the BaP concentrations, dynamics and decomposition in soil is required to assess the critical loads of BaP in urban environments. This study is the first attempt to evaluate all major input and output components of benzo[a]pyrene (BaP) balance and to calculate the permissible load on the urban environment in different land-use zones in the Eastern district of Moscow. BaP contamination of the snow cover in the Eastern district of Moscow was related to daily BaP fallout from the atmosphere. In 2010, the mean content of the pollutant in the snow dust was 1942 ng g-1, whereas the average intensity of its fallout was 7.13 ng m-2 per day. Across the territory, BaP winter fallout intensities varied from 0.3 to 1100 ng m-2 per day. The average BaP content in the surface (0-10 cm) soil horizons was 409 ng g-1, which is 83 times higher than the local background value and 20 times higher than the maximum permissible concentration (MPC) accepted in Russia. The variations in soil and snow BaP concentrations among different land-use zones were examined. A significant contribution of BaP from the atmosphere to urban soils was identified. Based on the measurements of BaP atmospheric fallout and BaP reserves in the soils, the critical loads of BaP for the land-use zones in the Eastern district were calculated for different values of degradation intensity and different exposure times. It was established that at an annual degradation intensity of 1-10 %, ecologically safe BaP levels in the soils of all land-use zones, excluding the agricultural zone, will only be reached after many decades or centuries.

Anthropogenic phosphorus (P) inputs to a river basin and their impacts on P fluxes along its upstream-downstream continuum

NASA Astrophysics Data System (ADS)

Zhang, Wangshou; Swaney, Dennis; Hong, Bongghi; Howarth, Robert

2017-04-01

Phosphorus (P) originating from anthropogenic sources as a pollutant of surface waters has been an environmental issue for decades because of the well-known role of P in eutrophication. Human activities, such as food production and rapid urbanization, have been linked to increased P inputs which are often accompanied by corresponding increases in riverine P export. However, uneven distributions of anthropogenic P inputs along watersheds from the headwaters to downstream reaches can result in significantly different contributions to the riverine P fluxes of a receiving water body. So far, there is still very little scientific understanding of anthropogenic P inputs and their impacts on riverine flux in river reaches along the upstream to downstream continuum. Here, we investigated P budgets in a series of nested watersheds draining into Hongze Lake of China, and developed a simple empirical function to describe the relationship between anthropogenic inputs and riverine TP fluxes. The results indicated that an average of 1.1% of anthropogenic P inputs are exported into rivers, with most of the remainder retained in the watershed landscape over the period studied. Fertilizer application was the main contributor of P loading to the lake (55% of total loads), followed by legacy P stock (30%), food and feed P inputs (12%) and non-food P inputs (4%). From 60% to 89% of the riverine TP loads generated from various locations within this basin were ultimately transported into the receiving lake of the downstream, with an average rate of 1.86 tons P km-1 retaining in the main stem of the inflowing river annually. Our results highlight that in-stream processes can significantly buffer the riverine P loading to the downstream receiving lake. An integrated P management strategy considering the influence of anthropogenic inputs and hydrological interactions is required to assess and optimize P management for protecting fresh waters.

Implementation of a national external quality assessment program for medical laboratories in Burkina Faso: challenges, lessons learned, and perspectives.

PubMed

Sakandé, Jean; Nikièma, Abdoulaye; Kabré, Elie; Sawadogo, Charles; Nacoulma, Eric W; Sanou, Mamadou; Sangaré, Lassana; Traoré-Ouédraogo, Rasmata; Sawadogo, Mamadou; Gershy-Damet, Guy Michel

2014-02-01

The National External Quality Assessment (NEQA) program of Burkina Faso is a proficiency testing program mandatory for all laboratories in the country since 2006. The program runs two cycles per year and covers all areas of laboratories. All panels were validated by the expert committee before dispatch under optimal storage and transport conditions to participating laboratories along with report forms. Performance in the last 5 years varied by panel, with average annual performance of bacteriology panels for all laboratories rising from 75% in 2006 to 81% in 2010 and with a best average performance of 87% in 2007 and 2008. During the same period, malaria microscopy performance varied from 85% to 94%, with a best average performance of 94% in 2010; chemistry performance increased from 87% to 94%, with a best average annual performance of 97% in 2009. Hematology showed more variation in performance, ranging from 61% to 86%, with a best annual average performance of 90% in 2008. Average annual performance for immunology varied less between 2006 and 2010, recording 97%, 90%, and 95%. Except for malaria microscopy, annual performances for enrolled panels varied substantially from year to year, indicating some difficulty in maintaining consistency in quality. The main challenges of the NEQA program observed between 2006 to 2010 were funding, sourcing, and safe transportation of quality panels to all laboratories countrywide.

25 CFR 30.116 - If a school fails to achieve its annual measurable objectives, what other methods may it use to...

Code of Federal Regulations, 2011 CFR

2011-04-01

... participated in the assessment. (b) Method B—Uniform Averaging Procedure. A school may use uniform averaging... 25 Indians 1 2011-04-01 2011-04-01 false If a school fails to achieve its annual measurable... Adequate Yearly Progress § 30.116 If a school fails to achieve its annual measurable objectives, what other...

25 CFR 30.116 - If a school fails to achieve its annual measurable objectives, what other methods may it use to...

Code of Federal Regulations, 2012 CFR

2012-04-01

... participated in the assessment. (b) Method B—Uniform Averaging Procedure. A school may use uniform averaging... 25 Indians 1 2012-04-01 2011-04-01 true If a school fails to achieve its annual measurable... Adequate Yearly Progress § 30.116 If a school fails to achieve its annual measurable objectives, what other...

25 CFR 30.116 - If a school fails to achieve its annual measurable objectives, what other methods may it use to...

Code of Federal Regulations, 2013 CFR

2013-04-01

... participated in the assessment. (b) Method B—Uniform Averaging Procedure. A school may use uniform averaging... 25 Indians 1 2013-04-01 2013-04-01 false If a school fails to achieve its annual measurable... Adequate Yearly Progress § 30.116 If a school fails to achieve its annual measurable objectives, what other...

25 CFR 30.116 - If a school fails to achieve its annual measurable objectives, what other methods may it use to...

Code of Federal Regulations, 2010 CFR

2010-04-01

... participated in the assessment. (b) Method B—Uniform Averaging Procedure. A school may use uniform averaging... 25 Indians 1 2010-04-01 2010-04-01 false If a school fails to achieve its annual measurable... Adequate Yearly Progress § 30.116 If a school fails to achieve its annual measurable objectives, what other...

25 CFR 30.116 - If a school fails to achieve its annual measurable objectives, what other methods may it use to...

Code of Federal Regulations, 2014 CFR

2014-04-01

... participated in the assessment. (b) Method B—Uniform Averaging Procedure. A school may use uniform averaging... 25 Indians 1 2014-04-01 2014-04-01 false If a school fails to achieve its annual measurable... Adequate Yearly Progress § 30.116 If a school fails to achieve its annual measurable objectives, what other...

Discernible rhythm in the spatio/temporal distributions of transatlantic dust

NASA Astrophysics Data System (ADS)

Ben-Ami, Y.; Koren, I.; Altaratz, O.; Kostinski, A. B.; Lehahn, Y.

2011-08-01

The differences in North African dust emission regions and transport routes, between the boreal winter and summer are thoroughly documented. Here we re-examine the spatial and temporal characteristics of dust transport over the tropical and subtropical North Atlantic Ocean, using 10 years of satellite data, in order to determine better the different dust transport periods and their characteristics. We see a robust annual triplet: a discernible rhythm of "transatlantic dust weather". The proposed annual partition is composed of two heavy loading periods, associated here with a northern-route period and southern-route period, and one clean, light-loading period, accompanied by unusually low average optical depth of dust. The two dusty periods are quite different in character: their duration, transport routes, characteristic aerosol loading and frequency of pronounced dust episodes. The southern route period lasts about ~4 months, from the end of November to end of March. It is characterized by a relatively steady southern positioning, low frequency of dust events, low background values and high variance in dust loading. The northern-route period lasts ~6.5 months, from the end of March to mid October, and is associated with a steady drift northward of ~0.1 latitude day-1, reaching ~1500 km north of the southern route. The northern period is characterized by higher frequency of dust events, higher (and variable) background and smaller variance in dust loading. It is less episodic than the southern period. Transitions between the periods are brief. Separation between the southern and northern periods is marked by northward latitudinal shift in dust transport and by moderate reduction in the overall dust loading. The second transition between the northern and southern periods commences with an abrupt reduction in dust loading (thereby initiating the clean period) and rapid shift southward of ~0.2 latitude day-1, and 1300 km in total. These rates of northward advance and southern retreat of the dust transport route are in accordance with the simultaneous shift of the Inter Tropical Front. Based on cross-correlation analyses, we attribute the observed rhythm to the contrast between the northwestern and southern Saharan dust source spatial distributions. Despite the vast difference in areas, the Bodélé Depression, located in Chad, appears to modulate transatlantic dust patterns about half the time. The proposed partition captures the essence of transatlantic dust climatology and may, therefore, supply a natural temporal framework for dust analysis via models and observations.

Satellite derived estimates of forest leaf area index in South-west Western Australia are not tightly coupled to inter-annual variations in rainfall: implications for groundwater decline in a drying climate.

NASA Astrophysics Data System (ADS)

Smettem, Keith; Waring, Richard; Callow, Nik; Wilson, Melissa; Mu, Qiaozhen

2013-04-01

There is increasing concern that widespread forest decline could occur in regions of the world where droughts are predicted to increase in frequency and severity as a result of climate change. Ecological optimality proposes that the long term average canopy size of undisturbed perennial vegetation is tightly coupled to climate. The average annual leaf area index (LAI) is an indicator of canopy cover and the difference between the annual maximum and minimum LAI is an indicator of annual leaf turnover. In this study we analysed satellite-derived estimates of monthly LAI across forested coastal catchments of South-west Western Australia over a 12 year period (2000-2011) that included the driest year on record for the last 60 years. We observed that over the 12 year study period, the spatial pattern of average annual satellite-derived LAI values was linearly related to mean annual rainfall. However, inter-annual changes to LAI in response to changes in annual rainfall were far less than expected from the long-term LAI-rainfall trend. This buffered response was investigated using a physiological growth model and attributed to availability of deep soil moisture and/or groundwater storage. The maintenance of high LAIs may be linked to a long term decline in areal average underground water storage storage and diminished summer flows, with a trend towards more ephemeral flow regimes.

Estimation of annual average daily traffic for off-system roads in Florida

DOT National Transportation Integrated Search

1999-07-28

Estimation of Annual Average Daily Traffic (AADT) is extremely important in traffic planning and operations for the state departments of transportation (DOTs), because AADT provides information for the planning of new road construction, determination...

CONTROL TECHNOLOGY EVALUATION FOR GASOLINE LOADING OF BARGES

EPA Science Inventory

The report gives results of a study to determine the feasibility, safety, and cost of methods to control the emission of hydrocarbon vapor during the loading of gasoline barges. Approximately 4 lb of hydrocarbons are emitted per 1000 gal. of gasoline loaded; annually about 1 mill...

Temporal variability and coloured noise of SLR translations with respect to the ITRF2014 origin

NASA Astrophysics Data System (ADS)

Riddell, Anna; King, Matt; Watson, Christopher; Rietbroek, Roelof; Sun, Yu; Riva, Riccardo

2017-04-01

Inferring large-scale environmental change, such as of sea-level change, glacial isostatic adjustment or ice sheet volume change (i.e. from altimetry), requires a geodetic reference frame stable to 0.1 mm/yr. Since 1988, each iterative improvement in the precision of the International Terrestrial Reference Frame (ITRF) has enabled significant advancement of scientific and technical research in the Earth sciences. We demonstrate the occurrence of coloured noise in the translation components between the SLR network and the long-term ITRF2014 origin from 1993.0 to 2015.0 with power law spectral indices close to -1, where white-noise-only linear trend uncertainties are underestimated by a factor of five in contrast to power-law linear trend uncertainties. The observed geocentre motion is expected to be influenced by the SLR observing network, known as the "network effect". Temporal translations in the SLR network may not necessarily average out over long time periods and therefore have the potential to shift the computed reference frame origin from the true long term centre of mass. Comparison with geophysical loading models demonstrates that the variability cannot be fully accounted for by surface mass transport such as changes in atmospheric, hydrologic or glacial loading. Our results demonstrate that the proportion of variance explained by geophysical surface loading is less than 50% in each translational component. Evidence of temporal variability in both the SLR amplitude and trend of the annual signal suggest that a different coloured noise model be considered in place of, or as an extension of, the traditional linear and white-noise-only model to represent the long-term average centre of mass.

An optimized network for phosphorus load monitoring for Lake Okeechobee, Florida

USGS Publications Warehouse

Gain, W.S.

1997-01-01

Phosphorus load data were evaluated for Lake Okeechobee, Florida, for water years 1982 through 1991. Standard errors for load estimates were computed from available phosphorus concentration and daily discharge data. Components of error were associated with uncertainty in concentration and discharge data and were calculated for existing conditions and for 6 alternative load-monitoring scenarios for each of 48 distinct inflows. Benefit-cost ratios were computed for each alternative monitoring scenario at each site by dividing estimated reductions in load uncertainty by the 5-year average costs of each scenario in 1992 dollars. Absolute and marginal benefit-cost ratios were compared in an iterative optimization scheme to determine the most cost-effective combination of discharge and concentration monitoring scenarios for the lake. If the current (1992) discharge-monitoring network around the lake is maintained, the water-quality sampling at each inflow site twice each year is continued, and the nature of loading remains the same, the standard error of computed mean-annual load is estimated at about 98 metric tons per year compared to an absolute loading rate (inflows and outflows) of 530 metric tons per year. This produces a relative uncertainty of nearly 20 percent. The standard error in load can be reduced to about 20 metric tons per year (4 percent) by adopting an optimized set of monitoring alternatives at a cost of an additional $200,000 per year. The final optimized network prescribes changes to improve both concentration and discharge monitoring. These changes include the addition of intensive sampling with automatic samplers at 11 sites, the initiation of event-based sampling by observers at another 5 sites, the continuation of periodic sampling 12 times per year at 1 site, the installation of acoustic velocity meters to improve discharge gaging at 9 sites, and the improvement of a discharge rating at 1 site.

Fine-grained channel margin (FGCM) deposits conditioned by Large Woody Debris (LWD) in a gravel-bed river

NASA Astrophysics Data System (ADS)

Skalak, K. J.; Pizzuto, J. E.

2006-12-01

The purpose of this research is to examine the origin, occurrence, persistence, residence time and general significance of fine-grained channel margin storage in South River, a steep gravel-bedded stream in western Virginia. Fine-grained channel margin (FGCM) deposits in this study refers to specific in-channel deposits of mud and sand. These deposits occur primarily in the margins and near-banks regions of the channel. Fine- grained sediment storage in the near-bank regions is a result of reduced velocity caused by the bank obstructions. Nearly all of these obstructions consist of LWD accumulations in the channel. Storage occurs in four different geomorphic settings: 1) long pooled sections caused by bedrock or old mill dams, 2) the upstream ends of pools in channel margins with LWD accumulations, 3) bank obstructions usually caused by trees, 4) side channel backwaters where flow separates around islands. In approximately 38 km of river, there is 3000 m3 of fine-grained sediment stored in these features. The channel stores approximately 15 percent its total annual suspended load as fine-grained channel margin deposits. Consequently, these features represent a significant component of an annual sediment budget for this river. On average, the FGCM deposits are about 35 cm deep, 20 m long, and 4 m wide. They average 30 percent mud, 68 percent sand, and 2 percent gravel. These deposits have been cored and analyzed for Hg, grain size, loss-on-ignition, and bomb radiocarbon. Results from bomb radiocarbon analysis indicate that these features have an average age of 13 years. High Hg concentrations in fish tissue are an ongoing problem along South River, further motivating detailed study of these deposits.

Modelling phosphorus transport and its response to climate change at upper stream of Poyang Lake-the largest fresh water lake in China

NASA Astrophysics Data System (ADS)

Jiang, Sanyuan; Zhang, Qi

2017-04-01

Phosphorus losses from excessive fertilizer application and improper land exploitation were found to be the limiting factor for freshwater quality deterioration and eutrophication. Phosphorus transport from uplands to river is related to hydrological, soil erosion and sediment transport processes, which is impacted by several physiographic and meteorological factors. The objective of this study was to investigate the spatiotemporal variation of phosphorus losses and response to climate change at a typical upstream tributary (Le'An river) of Poyang Lake. To this end, a process-oriented hydrological and nutrient transport model HYPE (Hydrological Predictions for the Environment) was set up for discharge and phosphorus transport simulation at Le'An catchment. Parameter ESTimator (PEST) was combined with HYPE model for parameter sensitivity analysis and optimisation. In runoff modelling, potential evapotranspiration rate of the dominant land use (forest) is most sensitive; parameters of surface runoff rate and percolation capacity for the red soil are also very sensitive. In phosphorus transport modelling, the exponent of equation for soil erosion processes induced by surface runoff is most sensitive, coefficient of adsorption/desorption processes for red soil is also very sensitive. Flow dynamics and water balance were simulated well at all sites for the whole period (1978-1986) with NSE≥0.80 and PBIAS≤14.53%. The optimized hydrological parameter set were transferable for the independent period (2009-2010) with NSE≥0.90 and highest PBIAS of -7.44% in stream flow simulation. Seasonal dynamics and balance of stream water TP (Total Phosphorus ) concentrations were captured satisfactorily indicated by NSE≥0.53 and highest PBIAS of 16.67%. In annual scale, most phosphorus is transported via surface runoff during heavy storm flow events, which may account for about 70% of annual TP loads. Based on future climate change analysis under three different emission scenarios (RCP 2.6, RCP 4.5 and RCP 8.5), there is no considerable change in average annual rainfall amount in 2020-2035 while increasing occurrence frequency and intensity of extreme rainfall events were predicted. The validated HYPE model was run on the three emission scenarios. Overall increase of TP loads was found in future with the largest increase of annual TP loads under the high emission scenario (RCP 8.5). The outcomes of this study (i) verified the transferability of HYPE model at humid subtropical and heterogeneous catchment; (ii) revealed the sensitive hydrological and phosphorus transport processes and relevant parameters; (iii) implied more TP losses in future in response to increasing extreme rainfall events.

Availability of streamflow for recharge of the basal aquifer in the Pearl Harbor area, Hawaii

USGS Publications Warehouse

Hirashima, George Tokusuke

1971-01-01

The Pearl Harbor area is underlain by an extensive basal aquifer that contains large supplies of fresh water. Because of the presence of a cap rock composed of sedimentary material that is less permeable than the basaltic lava of the basal aquifer, seaward movement of ground water is retarded. The cap rock causes the basal water to stand at a high level; thus, the lens of fresh water that floats on sea water is thick. Discharge from the basal ground-water body, which includes pumpage from wells and shafts, averaged 250 million gallons per day during 1931-65. Because the water level in the basal aquifer did not decline progressively, recharge to the ground-water body must have been approximately equal to discharge. Although pumping for agricultural use has decreased since 1931, net ground-water discharge has increased because of a large increase in pumping for urban use. Substitution of ground water for surface water in the irrigation of sugarcane has also contributed to a net increase in ground-water discharge. The development of Mililani Town will further increase discharge. The increase in ground-water discharge may cause an increase in chloride content of the water pumped from wells near the shore of Pearl Harbor unless the increased discharge is balanced by increased recharge to the local aquifer. The aquifer is recharged by direct infiltration and deep percolation of rain, principally in the high forested area, by infiltration and percolation of irrigation water applied in excess of plant requirements, by seepage of water through streambeds, and possibly by ground-water inflow from outside the area. Recharge is greatest in the uplands, where rainfall is heavy and where much infiltration takes place before rainwater collects in the middle and lower reaches of stream channels. Once water collects in and saturates the alluvium of stream channels, additional inflow to the streams will flow out to sea, only slightly decreased by seepage. Average annual direct runoff from the 90-square-mile Pearl Harbor area is 47.27 million gallons per day, or 11.1 inches; this is 13.3 percent of the average annual rainfall (83.3 in.) over the area. Average annual direct runoff in streams at the 800- and 400-foot altitudes is 29 and 38 million gallons per day, respectively. Kipapa Stream has the largest average annual direct runoff at those altitudes--6 and 9 million gallons per day, respectively. Because streams are flashy and have a wide range in discharge, only 60 percent of the average annual runoff can be economically diverted through ditches to recharge areas. The diversion may be increased slightly if reservoirs are used in conjunction with ditches to temporarily detain flows in excess of ditch capacity. The planned irrigation use of some of the perennial flow available in Waikele Stream near sea level will decrease pumping from and increase recharge to the basal aquifer. Suspended-sediment load is mainly silt and clay, and it increases rapidly with increased discharge. Thus, the use of streamflow for artificial recharge poses problems. High flows must be used if recharge is to be effective, but flows must not be so high as to cause clogging of recharge facilities with sediment or woodland debris. Practical tests are needed to determine the advantages and disadvantages of different types of recharge structures, such as a reservoir or basin, large-diameter deep shafts, deep wells, or combinations of all these structures.

The importance of considering shifts in seasonal changes in discharges when predicting future phosphorus loads in streams

USGS Publications Warehouse

LaBeau, Meredith B.; Mayer, Alex S.; Griffis, Veronica; Watkins, David Jr.; Robertson, Dale M.; Gyawali, Rabi

2015-01-01

In this work, we hypothesize that phosphorus (P) concentrations in streams vary seasonally and with streamflow and that it is important to incorporate this variation when predicting changes in P loading associated with climate change. Our study area includes 14 watersheds with a range of land uses throughout the U.S. Great Lakes Basin. We develop annual seasonal load-discharge regression models for each watershed and apply these models with simulated discharges generated for future climate scenarios to simulate future P loading patterns for two periods: 2046–2065 and 2081–2100. We utilize output from the Coupled Model Intercomparison Project phase 3 downscaled climate change projections that are input into the Large Basin Runoff Model to generate future discharge scenarios, which are in turn used as inputs to the seasonal P load regression models. In almost all cases, the seasonal load-discharge models match observed loads better than the annual models. Results using the seasonal models show that the concurrence of nonlinearity in the load-discharge model and changes in high discharges in the spring months leads to the most significant changes in P loading for selected tributaries under future climate projections. These results emphasize the importance of using seasonal models to understand the effects of future climate change on nutrient loads.

Developing a passive load reduction blade for the DTU 10 MW reference turbine

NASA Astrophysics Data System (ADS)

de Vaal, J. B.; Nygaard, T. A.; Stenbro, R.

2016-09-01

This paper presents the development of a passive load reduction blade for the DTU 10 MW reference wind turbine, using the aero-hydro-servo-elastic analysis tool 3DFloat. Passive load reduction is achieved by introducing sweep to the path of the blade elastic axis, so that out-of-plane bending deflections result in load alleviating torsional deformations of the blade. Swept blades are designed to yield similar annual energy production as a rotor with a reference straight blade. This is achieved by modifying the aerodynamic twist distribution for swept blades based on non-linear blade deflection under steady state loads. The passive load reduction capability of a blade design is evaluated by running a selection of fatigue- and extreme load cases with the analysis tool 3DFloat and determining equivalent fatigue loads, fatigue damage and extreme loads at the blade root and tower base. The influence of sweep on the flutter speed of a blade design is also investigated. A large number of blade designs are evaluated by varying the parameters defining the sweep path of a blade's elastic axis. Results show that a moderate amount of sweep can effectively reduce equivalent fatigue damage and extreme loads, without significantly reducing the flutter speed, or compromising annual energy production.

NREL: International Activities - Afghanistan Resource Maps

Science.gov Websites

facilities, load centers, terrain conditions, and land use. The high-resolution (1-km) annual wind power maps . The high-resolution (10-km) annual and seasonal solar resource maps were developed using weather -km Resolution Annual Maps (Direct) Low-Res (JPG 104 KB) | High-Res (ZIP 330 KB) 40-km Resolution

40 CFR 439.52 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2012 CFR

2012-07-01

..., kg) per day, must reflect not less than 74 percent reduction in the long-term average daily COD load... long-term average daily BOD5 or COD mass loading of the raw process wastewater (i.e., the base number..., calculation of the long-term average daily BOD5 or COD load in the influent to the wastewater treatment system...

40 CFR 439.52 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2014 CFR

2014-07-01

..., kg) per day, must reflect not less than 74 percent reduction in the long-term average daily COD load... long-term average daily BOD5 or COD mass loading of the raw process wastewater (i.e., the base number..., calculation of the long-term average daily BOD5 or COD load in the influent to the wastewater treatment system...

40 CFR 439.52 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2013 CFR

2013-07-01

..., kg) per day, must reflect not less than 74 percent reduction in the long-term average daily COD load... long-term average daily BOD5 or COD mass loading of the raw process wastewater (i.e., the base number..., calculation of the long-term average daily BOD5 or COD load in the influent to the wastewater treatment system...

40 CFR 439.12 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2013 CFR

2013-07-01

... than 90 percent reduction in the long-term average daily BOD5 load of the raw (untreated) process wastewater, multiplied by a variability factor of 3.0. (1) The long-term average daily BOD5 load of the raw..., calculation of the long-term average daily BOD5 load in the influent to the wastewater treatment system must...

40 CFR 439.12 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2012 CFR

2012-07-01

... than 90 percent reduction in the long-term average daily BOD5 load of the raw (untreated) process wastewater, multiplied by a variability factor of 3.0. (1) The long-term average daily BOD5 load of the raw..., calculation of the long-term average daily BOD5 load in the influent to the wastewater treatment system must...

40 CFR 439.12 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2014 CFR

2014-07-01

... than 90 percent reduction in the long-term average daily BOD5 load of the raw (untreated) process wastewater, multiplied by a variability factor of 3.0. (1) The long-term average daily BOD5 load of the raw..., calculation of the long-term average daily BOD5 load in the influent to the wastewater treatment system must...

76 FR 79579 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-22

... posting of the availability of the submittal on EPA's Adequacy Web site (at http://www.epa.gov/otaq... average annual fourth-highest daily maximum 8-hour average ozone concentration), if it had a 1-hour design... ozone standard is attained when the three-year average of the annual fourth-highest daily maximum 8-hour...

Load Balancing Using Time Series Analysis for Soft Real Time Systems with Statistically Periodic Loads

NASA Technical Reports Server (NTRS)

Hailperin, Max

1993-01-01

This thesis provides design and analysis of techniques for global load balancing on ensemble architectures running soft-real-time object-oriented applications with statistically periodic loads. It focuses on estimating the instantaneous average load over all the processing elements. The major contribution is the use of explicit stochastic process models for both the loading and the averaging itself. These models are exploited via statistical time-series analysis and Bayesian inference to provide improved average load estimates, and thus to facilitate global load balancing. This thesis explains the distributed algorithms used and provides some optimality results. It also describes the algorithms' implementation and gives performance results from simulation. These results show that our techniques allow more accurate estimation of the global system load ing, resulting in fewer object migration than local methods. Our method is shown to provide superior performance, relative not only to static load-balancing schemes but also to many adaptive methods.

Methods for Estimating Annual Wastewater Nutrient Loads in the Southeastern United States

USGS Publications Warehouse

McMahon, Gerard; Tervelt, Larinda; Donehoo, William

2007-01-01

This report describes an approach for estimating annual total nitrogen and total phosphorus loads from point-source dischargers in the southeastern United States. Nutrient load estimates for 2002 were used in the calibration and application of a regional nutrient model, referred to as the SPARROW (SPAtially Referenced Regression On Watershed attributes) watershed model. Loads from dischargers permitted under the National Pollutant Discharge Elimination System were calculated using data from the U.S. Environmental Protection Agency Permit Compliance System database and individual state databases. Site information from both state and U.S. Environmental Protection Agency databases, including latitude and longitude and monitored effluent data, was compiled into a project database. For sites with a complete effluent-monitoring record, effluent-flow and nutrient-concentration data were used to develop estimates of annual point-source nitrogen and phosphorus loads. When flow data were available but nutrient-concentration data were missing or incomplete, typical pollutant-concentration values of total nitrogen and total phosphorus were used to estimate load. In developing typical pollutant-concentration values, the major factors assumed to influence wastewater nutrient-concentration variability were the size of the discharger (the amount of flow), the season during which discharge occurred, and the Standard Industrial Classification code of the discharger. One insight gained from this study is that in order to gain access to flow, concentration, and location data, close communication and collaboration are required with the agencies that collect and manage the data. In addition, the accuracy and usefulness of the load estimates depend on the willingness of the states and the U.S. Environmental Protection Agency to provide guidance and review for at least a subset of the load estimates that may be problematic.

Quality of wet deposition in the Grand Calumet River watershed, northwestern Indiana, June 30, 1992-August 31, 1993

USGS Publications Warehouse

Willoughby, T.C.

1995-01-01

Northwestern Indiana is one of the most heavily industrialized and largest steel-producing areas in the United States. High temperature processes, such as fossil-fuel combustion and steel production, release contaminants to the atmosphere that may result in wet deposition being a major contributor to major ion and trace-metal loadings in north- western Indiana and Lake Michigan. A wet-deposition collection site was established at the Gary (Indiana) Regional Airport in June 1992 to monitor the chemical quality of wet deposition. Weekly samples were collected at this site from June 30, 1992, through August 31, 1993, and were analyzed for pH, specific conductance, and selected major ions and trace metals. Forty-eight samples collected during the study were of sufficient volumes for some of the determinations to be performed. Median constituent concentrations were determined for samples collected during warm weather and cold weather (November 1 through March 31). Median concentrations were substituted for missing values from samples with insufficient volumes for analysis of all the constituents of interest. Constituent concentrations were converted to weekly loadings. Two values were calculated to provide a range for the weekly loading for samples with measured concentrations of constituents less than the method reporting limit. The minimum weekly loading was computed by substituting zero for the constituent concentration; the maximum weekly loading was computed by substituting the method reporting limit for the concentration. If all of the sample concentrations measured were greater than the method reporting limit, an annual loading value was computed. The annual loadings could be used to assist in estimating the contribution of wet deposition to the total annual constituent loadings in the Grand Calumet River in northwestern Indiana.

Suspended sediment measurements and calculation of the particle load at HPP Fieschertal

NASA Astrophysics Data System (ADS)

Felix, D.; Albayrak, I.; Abgottspon, A.; Boes, R. M.

2016-11-01

In the scope of a research project on hydro-abrasive erosion of Pelton turbines, a field study was conducted at the high-head HPP Fieschertal in Valais, Switzerland. The suspended sediment mass concentration (SSC) and particle size distribution (PSD) in the penstock have been continuously measured since 2012 using a combination of six measuring techniques. The SSC was on average 0.52 g/l and rose to 50 g/l in a major flood event in July 2012. The median particle size d 50 was usually 15 pm, rising up to 100 μm when particles previously having settled in the headwater storage tunnel were re-suspended at low water levels. The annual suspended sediment loads (SSL) varied considerably depending on flood events. Moreover, so-called particle loads (PLs) according to the relevant guideline of the International Electrotechnical Commission (IEC 62364) were calculated using four relations between particle size and the relative abrasion potential. For the investigated HPP, the time series of the SSL and the PLs had generally similar shapes over the three years. The largest differences among the PLs were observed during re-suspension events when the particles were considerably coarser than usual. Further investigations on the effects of particle sizes on hydroabrasive erosion of splitters and cut-outs of coated Pelton turbines are recommended.

Evaluation of nutrient retention in vegetated filter strips using the SWAT model.

PubMed

Elçi, Alper

2017-11-01

Nutrient fluxes in stream basins need to be controlled to achieve good water quality status. In stream basins with intensive agricultural activities, nutrients predominantly come from diffuse sources. Therefore, best management practices (BMPs) are increasingly implemented to reduce nutrient input to streams. The objective of this study is to evaluate the impact of vegetated filter strip (VFS) application as an agricultural BMP. For this purpose, SWAT is chosen, a semi-distributed water quality assessment model that works at the watershed scale, and applied on the Nif stream basin, a small-sized basin in Western Turkey. The model is calibrated with an automated procedure against measured monthly discharge data. Nutrient loads for each sub-basin are estimated considering basin-wide data on chemical fertilizer and manure usage, population data for septic tank effluents and information about the land cover. Nutrient loads for 19 sub-basins are predicted on an annual basis. Average total nitrogen and total phosphorus loads are estimated as 47.85 t/yr and 13.36 t/yr for the entire basin. Results show that VFS application in one sub-basin offers limited retention of nutrients and that a selection of 20-m filter width is most effective from a cost-benefit perspective.

GIS Tools to Estimate Average Annual Daily Traffic

DOT National Transportation Integrated Search

2012-06-01

This project presents five tools that were created for a geographical information system to estimate Annual Average Daily : Traffic using linear regression. Three of the tools can be used to prepare spatial data for linear regression. One tool can be...

West Bank of the Mississippi River in the Vicinity of New Orleans, Louisiana (East of the Harvey Canal) Hurricane Protection Study. Technical Appendixes. Volume 2

DTIC Science & Technology

1994-08-01

ANNUAL PRECIPITATION, 30-YEAR NORMALS (1951-1980) A-I-3 A-I-2 MEAN MONTHLY AND ANNUAL TEMPERATURE , 30-YEAR NORMALS (1951-1980) A-I-4 A-1-3 AVERAGE ...Environmental Quality (DEQ). CLIMATE The climate of the area is humid si!btropicl. AMual average temperature in the project area is 68°F, with monthly...normal temperatures varying from 82’F in July to 531F in Januwry. Average annual precipitation over tae area is 63 inche!, maiying from a monthly

Temporal trends in water-quality constituent concentrations and annual loads of chemical constituents in Michigan watersheds, 1998–2013

USGS Publications Warehouse

Hoard, Christopher J.; Fogarty, Lisa R.; Duris, Joseph W.

2018-02-21

In 1998, the Michigan Department of Environmental Quality and the U.S. Geological Survey began the Water Chemistry Monitoring Program for select streams in the State of Michigan. Objectives of this program were to provide assistance with (1) statewide water-quality assessments, (2) the National Pollutant Discharge Elimination System permitting process, and (3) water-resource management decisions. As part of this program, water-quality data collected from 1998 to 2013 were analyzed to identify potential trends for select constituents that were sampled. Sixteen water-quality constituents were analyzed at 32 stations throughout Michigan. Trend analysis on the various water-quality data was done using either the uncensored Seasonal Kendall test or through Tobit regression. In total, 79 trends were detected in the constituents analyzed for 32 river stations sampled for the study period—53 downward trends and 26 upward trends were detected. The most prevalent trend detected throughout the State was for ammonia, with 11 downward trends and 1 upward trend estimated.In addition to trends, constituent loads were estimated for 31 stations from 2002 to 2013 for stations that were sampled 12 times per year. Loads were computed using the Autobeale load computation program, which used the Beale ratio estimator approach to estimate an annual load. Constituent loads were the largest in large watershed streams with the highest annual flows such as the Saginaw and Grand Rivers. Likewise, constituent loads were the smallest in smaller tributaries that were sampled as part of this program such as the Boardman and Thunder Bay Rivers.

Load Balancing Using Time Series Analysis for Soft Real Time Systems with Statistically Periodic Loads

NASA Technical Reports Server (NTRS)

Hailperin, M.

1993-01-01

This thesis provides design and analysis of techniques for global load balancing on ensemble architectures running soft-real-time object-oriented applications with statistically periodic loads. It focuses on estimating the instantaneous average load over all the processing elements. The major contribution is the use of explicit stochastic process models for both the loading and the averaging itself. These models are exploited via statistical time-series analysis and Bayesian inference to provide improved average load estimates, and thus to facilitate global load balancing. This thesis explains the distributed algorithms used and provides some optimality results. It also describes the algorithms' implementation and gives performance results from simulation. These results show that the authors' techniques allow more accurate estimation of the global system loading, resulting in fewer object migrations than local methods. The authors' method is shown to provide superior performance, relative not only to static load-balancing schemes but also to many adaptive load-balancing methods. Results from a preliminary analysis of another system and from simulation with a synthetic load provide some evidence of more general applicability.

Phosphorus Loading Trends in Lake Michigan: A Historic Surprise

EPA Science Inventory

Total phosphorus (TP) loads to the Great Lakes have been of interest to researchers since the 1960s. The International Joint Commission (IJC) was the primary source of Great Lakes TP loading data during the 1970s and 1980s when the IJC released annual reports detailing Great Lake...

Annual trace-metal load estimates and flow-weighted concentrations of cadmium, lead, and zinc in the Spokane River basin, Idaho and Washington, 1999-2004

USGS Publications Warehouse

Donato, Mary M.

2006-01-01

Streamflow and trace-metal concentration data collected at 10 locations in the Spokane River basin of northern Idaho and eastern Washington during 1999-2004 were used as input for the U.S. Geological Survey software, LOADEST, to estimate annual loads and mean flow-weighted concentrations of total and dissolved cadmium, lead, and zinc. Cadmium composed less than 1 percent of the total metal load at all stations; lead constituted from 6 to 42 percent of the total load at stations upstream from Coeur d'Alene Lake and from 2 to 4 percent at stations downstream of the lake. Zinc composed more than 90 percent of the total metal load at 6 of the 10 stations examined in this study. Trace-metal loads were lowest at the station on Pine Creek below Amy Gulch, where the mean annual total cadmium load for 1999-2004 was 39 kilograms per year (kg/yr), the mean estimated total lead load was about 1,700 kg/yr, and the mean annual total zinc load was 14,000 kg/yr. The trace-metal loads at stations on North Fork Coeur d'Alene River at Enaville, Ninemile Creek, and Canyon Creek also were relatively low. Trace-metal loads were highest at the station at Coeur d'Alene River near Harrison. The mean annual total cadmium load was 3,400 kg/yr, the mean total lead load was 240,000 kg/yr, and the mean total zinc load was 510,000 kg/yr for 1999-2004. Trace-metal loads at the station at South Fork Coeur d'Alene River near Pinehurst and the three stations on the Spokane River downstream of Coeur d'Alene Lake also were relatively high. Differences in metal loads, particularly lead, between stations upstream and downstream of Coeur d'Alene Lake likely are due to trapping and retention of metals in lakebed sediments. LOADEST software was used to estimate loads for water years 1999-2001 for many of the same sites discussed in this report. Overall, results from this study and those from a previous study are in good agreement. Observed differences between the two studies are attributable to streamflow differences in the two regression models, 1999-2001 and 1999-2004. Flow-weighted concentrations (FWCs) calculated from the estimated loads for 1999-2004 were examined to aid interpretation of metal load estimates, which were influenced by large spatial and temporal variations in streamflow. FWCs of total cadmium ranged from 0.04 micrograms per liter (?g/L) at Enaville to 14 ?g/L at Ninemile Creek. Total lead FWCs were lowest at Long Lake (1.3 ?g/L) and highest at Ninemile Creek (120 ?g/L). Elevated total lead FWCs at Harrison confirmed that the high total lead loads at this station were not simply due to higher streamflow. Conversely, relatively low total lead loads combined with high total lead FWCs at Ninemile and Canyon Creeks reflected low streamflow but high concentrations of total lead. Very low total lead FWCs (1.3 to 2.7 ?g/L) at the stations downstream of Coeur d'Alene Lake are a result both of deposition of lead-laden sediments in the lake and dilution by additional streamflow. Total zinc FWCs also demonstrated the effect of streamflow on load calculations, and highlighted source areas for zinc in the basin. Total zinc FWCs at Canyon and Ninemile Creeks, 1,600 ?g/L and 2,200 ?g/L, respectively, were by far the highest in the basin but contributed among the lowest total zinc loads due to their relatively low streamflow. Total zinc FWCs ranged from 38 to 67 ?g/L at stations downstream of Coeur d'Alene Lake, but total zinc load estimates at these stations were relatively high because of high mean streamflow compared to other stations in the basin. Long-term regression models for 1991 to 2003 or 2004 were developed and annual trace-metal loads and FWCs were estimated for Pinehurst, Enaville, Harrison, and Post Falls to better understand the variability of metal loading with time. Long-term load estimates are similar to the results for 1999-2004 in terms of spatial distribution of metal loads throughout the basin. LOADEST results for 1991-2004 indicated that statistically significant downward temporal trends for dissolved and total cadmium, dissolved zinc, and total lead were occurring at Pinehurst, Enaville, Harrison, and Post Falls. Additionally, data for Enaville and Post Falls showed significant downward trends for dissolved lead and total zinc loads; Harrison total zinc loads also decreased with time. The Mann-Kendall trend test results agreed with the LOADEST trend results in most cases, but gave contradictory results for total zinc at Pinehurst and at Post Falls. Long- and short-term load and flow-weighted concentration estimates yielded valuable information about metal storage and transport processes, and demonstrated that water quality data are a great aid in understanding these processes.

National Economic Development Procedures Manual. Coastal Storm Damage and Erosion

DTIC Science & Technology

1991-09-01

study area is temperate with warm summers and moderate winters. The annual temperature averages approximately 53 degrees Fahrenheit (*F). On average ...January is the coolest month with a mean temperature of 32°F and July is the warmest month. The average annual precipitation is about 45 inches with...0704.0188 Public rooing burden for rhr$ LoIlecton of ,nformaton .s estma eO to average I hour oer resiorse including the time for resrewing inttuctiOn

Assessment of total nitrogen in the upper Connecticut River basin in New Hampshire, Vermont, and Massachusetts, December 2002-September 2005

USGS Publications Warehouse

Deacon, Jeffrey R.; Smith, Thor E.; Johnston, Craig M.; Moore, Richard B.; Blake, Laura J.; Weidman, Rebecca M.

2006-01-01

A study of total nitrogen concentrations and loads was conducted from December 2002 to September 2005 at 13 river sites in the upper Connecticut River Basin. Ten sites were selected to represent contributions of nitrogen from forested, agricultural, and urban land. Three sites were distributed spatially on the main stem of the Connecticut River to assess the cumulative total nitrogen loads. To further improve the understanding of the sources and concentrations and loads of total nitrogen in the upper Connecticut River Basin, ambient surface water-quality sampling was supplemented with sampling of effluent from 19 municipal and paper mill wastewater-treatment facilities. Mean concentrations of total nitrogen ranged from 0.19 to 2.8 milligrams per liter (mg/L) at river sampling sites. Instantaneous mean loads of total nitrogen ranged from 162 to 58,300 pounds per day (lb/d). Estimated mean annual loads of total nitrogen ranged from 49,100 to 21.6 million pounds per year (lb/yr) with about 30 to 55 percent of the loads being transported during the spring. The estimated mean annual yields of total nitrogen ranged from 1,190 to 7,300 pounds per square mile per year (lb/mi2)/yr. Mean concentrations of total nitrogen ranged from 4.4 to 30 mg/L at wastewater-treatment sampling sites. Instantaneous mean loads of total nitrogen from municipal wastewater-treatment facilities ranged from 36 to 1,780 lb/d. Instantaneous mean loads of total nitrogen from paper mill wastewater-treatment facilities ranged from 96 to 160 lb/d. The median concentration of total nitrogen was 0.24 mg/L at forested sites, 0.48 mg/L at agricultural sites, 0.54 mg/L at urban sites, 0.48 mg/L at main-stem sites, and 14 mg/L at wastewater-treatment sites. Concentrations of total nitrogen at forested sites were significantly less than at all other site types (p0.05) but were significantly greater (p<0.05) than at forested sites and significantly less than concentrations at wastewater-treatment sites (p<0.05). Total nitrogen concentrations at wastewater-treatment sites were significantly different from all other site types (p<0.05). Annual yields of total nitrogen ranged from 732 to 1,920 (lb/mi2)/yr at forested sites; 1,550 to 2,980 (lb/mi2)/yr at agricultural sites; 1,280 to 1,860 (lb/mi2)/yr at urban sites that were not directly affected by wastewater effluent; 7,090 to 7,770 (lb/mi2)/yr at an urban site directly affected by wastewater effluent; and 1,300 to 2,390 (lb/mi2)/yr at main-stem sites. In this study, the mean annual load and yield of total nitrogen at the Connecticut River at Wells River, VT, was estimated at 4.47 million lb/yr and 1,690 (lb/mi2)/yr, respectively. The mean annual load and yield of total nitrogen at the Connecticut River at North Walpole, NH, was estimated at 9.60 million lb/yr and 1,750 (lb/mi2)/yr, respectively. The mean annual load and yield of total nitrogen leaving the upper Connecticut River Basin, as estimated at the Connecticut River at Thompsonville, CT, was 21.6 million lb/yr and 2,230 (lb/mi2)/yr, respectively.

EnviroAtlas - Biological nitrogen fixation in natural/semi-natural ecosystems by 12-digit HUC for the Conterminous United States, 2006

EPA Pesticide Factsheets

This EnviroAtlas dataset contains data on the mean biological nitrogen fixation in natural/semi-natural ecosystems per 12-digit Hydrologic Unit (HUC) in 2006. Biological N fixation (BNF) in natural/semi-natural ecosystems was estimated using a correlation with actual evapotranspiration (AET). This correlation is based on a global meta-analysis of BNF in natural/semi-natural ecosystems (Cleveland et al. 1999). AET estimates for 2006 were calculated using a regression equation describing the correlation of AET with climate (average annual daily temperature, average annual minimum daily temperature, average annual maximum daily temperature, and annual precipitation) and land use/land cover variables in the conterminous US (Sanford and Selnick 2013). Data describing annual average minimum and maximum daily temperatures and total precipitation for 2006 were acquired from the PRISM climate dataset (http://prism.oregonstate.edu). Average annual climate data were then calculated for individual 12-digit USGS Hydrologic Unit Codes (HUC12s; http://water.usgs.gov/GIS/huc.html; 22 March 2011 release) using the Zonal Statistics tool in ArcMap 10.0. AET for individual HUC12s was estimated using equations described in Sanford and Selnick (2013). BNF in natural/semi-natural ecosystems within individual HUC12s was modeled with an equation describing the statistical relationship between BNF (kg N ha-1 yr-1) and actual evapotranspiration (AET; cm yr-1) and scaled to the proportion

Improving water quality in the Chesapeake Bay using payments for ecosystem services for perennial biomass for bioenergy and biofuel production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodbury, Peter B.; Kemanian, Armen R.; Jacobson, Michael

Replacing row crops with perennial bioenergy crops may reduce nitrogen (N) loading to surface waters. We estimated the benefits, costs, and potential for replacing maize with switchgrass to meet required N loading reduction targets for the Chesapeake Bay (CB) of 26.9 Gg -1. After subtracting the potential reduction in N loading due to improved N fertilizer practices for maize, a further 22.8 Gg reduction is required. Replacing maize with fertilized switchgrass could reduce N loading to the CB by 18 kg ha -1 y -1, meeting 31% of the N reduction target. The break-even price of fertilized switchgrass to providemore » the same profit as maize in the CB is 111 $Mg -1 (oven-dry basis throughout). Growers replacing maize with switchgrass could receive an ecosystem service payment of 148 ha -1 based on the price paid in Maryland for planting a rye cover crop. For our estimated average switchgrass yield of 9.9 Mg ha -1, and the greater N loading reduction of switchgrass compared to a cover crop, this equates to 24 dollars Mg -1. The annual cost of this ecosystem service payment to induce switchgrass planting is 13.29 dollars kg -1 of N. Using the POLYSYS model to account for competition among food, feed, and biomass markets, we found that with the ecosystem service payment for switchgrass of 25 $ Mg -1 added to a farm-gate price of 111 dollars Mg -1, 11% of the N loading reduction target could be met while also producing 1.3 Tg of switchgrass, potentially yielding 420 dam 3 y -1 of ethanol.« less

Improving water quality in the Chesapeake Bay using payments for ecosystem services for perennial biomass for bioenergy and biofuel production

DOE PAGES

Woodbury, Peter B.; Kemanian, Armen R.; Jacobson, Michael; ...

2017-02-03

Replacing row crops with perennial bioenergy crops may reduce nitrogen (N) loading to surface waters. We estimated the benefits, costs, and potential for replacing maize with switchgrass to meet required N loading reduction targets for the Chesapeake Bay (CB) of 26.9 Gg -1. After subtracting the potential reduction in N loading due to improved N fertilizer practices for maize, a further 22.8 Gg reduction is required. Replacing maize with fertilized switchgrass could reduce N loading to the CB by 18 kg ha -1 y -1, meeting 31% of the N reduction target. The break-even price of fertilized switchgrass to providemore » the same profit as maize in the CB is 111 $Mg -1 (oven-dry basis throughout). Growers replacing maize with switchgrass could receive an ecosystem service payment of 148 ha -1 based on the price paid in Maryland for planting a rye cover crop. For our estimated average switchgrass yield of 9.9 Mg ha -1, and the greater N loading reduction of switchgrass compared to a cover crop, this equates to 24 dollars Mg -1. The annual cost of this ecosystem service payment to induce switchgrass planting is 13.29 dollars kg -1 of N. Using the POLYSYS model to account for competition among food, feed, and biomass markets, we found that with the ecosystem service payment for switchgrass of 25 $ Mg -1 added to a farm-gate price of 111 dollars Mg -1, 11% of the N loading reduction target could be met while also producing 1.3 Tg of switchgrass, potentially yielding 420 dam 3 y -1 of ethanol.« less

Evaluation of long-term trends in hydrologic and water-quality conditions, and estimation of water budgets through 2013, Chester County, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.; Reif, Andrew G.

2017-06-02

An evaluation of trends in hydrologic and water quality conditions and estimation of water budgets through 2013 was done by the U.S. Geological Survey in cooperation with the Chester County Water Resources Authority. Long-term hydrologic, meteorologic, and biologic data collected in Chester County, Pennsylvania, which included streamflow, groundwater levels, surface-water quality, biotic integrity, precipitation, and air temperature were analyzed to determine possible trends or changes in hydrologic conditions. Statistically significant trends were determined by applying the Kendall rank correlation test; the magnitudes of the trends were determined using the Sen slope estimator. Water budgets for eight selected watersheds were updated and a new water budget was developed for the Marsh Creek watershed. An average water budget for Chester County was developed using the eight selected watersheds and the new Marsh Creek water budget.Annual and monthly mean streamflow, base flow, and runoff were analyzed for trends at 10 streamgages. The periods of record at the 10 streamgages ranged from 1961‒2013 to 1988‒2013. The only statistically significant trend for annual mean streamflow was for West Branch Brandywine Creek near Honey Brook, Pa. (01480300) where annual mean streamflow increased 1.6 cubic feet per second (ft3/s) per decade. The greatest increase in monthly mean streamflow was for Brandywine Creek at Chadds Ford, Pa. (01481000) for December; the increase was 47 ft3/s per decade. No statistically significant trends in annual mean base flow or runoff were determined for the 10 streamgages. The greatest increase in monthly mean base flow was for Brandywine Creek at Chadds Ford, Pa. (01481000) for December; the increase was 26 ft3/s per decade.The magnitude of peaks greater than a base streamflow was analyzed for trends for 12 streamgages. The period of record at the 12 stream gages ranged from 1912‒2012 to 2004–11. Fifty percent of the streamgages showed a small statistically significant increase in peaks greater than the base streamflow. The greatest increase was for Brandywine Creek at Chadds Ford, Pa. (01481000) during 1962‒2012; the increase was 1.8 ft3/s per decade. There were no statistically significant trends in the number of floods equal to or greater than the 2-year recurrence interval flood flow.Twenty‒one monitoring wells were evaluated for statistically significant trends in annual mean water level, minimum annual water level, maximum annual water level, and annual range in water-level fluctuations. For four wells, a small statistically significant increase in annual mean water level was determined that ranged from 0.16 to 0.7 feet per decade. There was poor or no correlation between annual mean groundwater levels and annual mean streamflow and base flow. No correlation was determined between annual mean groundwater level and annual precipitation. Despite rapid population growth and land-use change since 1950, there appears to have been little or no detrimental effects on groundwater levels in 21 monitoring wells.Long-term precipitation and temperature data were available from the West Chester (1893‒2013) and Phoenixville, Pa. (1915‒2013) National Oceanic and Atmospheric Administration (NOAA) weather stations. No statistically significant trends in annual mean precipitation or annual mean temperature were determined for either station. Both weather stations had a significant decrease in the number of days per year with precipitation greater than or equal to 0.1 inch. Annual mean minimum and maximum temperatures from the NOAA Southeastern Piedmont Climate Division increased 0.2 degrees Fahrenheit (F) per decade between 1896 and 2014. The number of days with a maximum temperature equal to or greater than 90 degrees F increased at West Chester and decreased at Phoenixville. No statistically significant trend was determined for annual snowfall amounts.Data from 1974 to 2013 for three stream water-quality monitors in the Brandywine Creek watershed were evaluated. The monitors are on the West Branch Brandywine Creek at Modena, Pa. (01480617), East Branch Brandywine Creek below Downingtown, Pa. (01480870), and Brandywine Creek at Chadds Ford, Pa. (01481000). Statistically significant upward trends were determined for annual mean specific conductance at all three stations, indicating the total dissolved solids load has been increasing. If the current trend continues, the annual mean specific conductance could almost double from 1974 to 2050. The increase in specific conductance likely is due to increases in chloride concentrations, which have been increasing steadily over time at all three stations. No correlation was found between monthly mean specific conductance and monthly mean streamflow or base flow. Statistically significant upward trends in pH were determined for all three stations. Statistically significant upward trends in stream temperature were determined for East Branch Brandywine Creek below Downingtown, Pa. (01480870) and Brandywine Creek at Chadds Ford, Pa. (01481000). The stream water-quality data indicate substantial increases in the minimum daily dissolved oxygen concentrations in the Brandywine Creek over time.The Chester County Index of Biotic Integrity (CC-IBI) determined for 1998‒2013 was evaluated for the five biological sampling sites collocated with streamgages. CC-IBI scores are based on a 0‒100 scale with higher scores indicating better stream quality. Statistically significant upward trends in the CC-IBI were determined for West Branch Brandywine Creek at Modena, Pa. (01480617) and East Branch Brandywine Creek below Downingtown, Pa. (01480870). No correlation was found between the CC-IBI and streamflow, precipitation, or stream specific conductance, pH, temperature, or dissolved oxygen concentration.A Chester County average water budget was developed using the nine estimated watershed water budgets. Average precipitation was 48.4 inches, and average streamflow was 21.4 inches. Average runoff and base flow were 8.3 and 13.1 inches, respectively, and average evapotranspiration and estimation of errors was 27.2 inches."

Future climate and land uses effects on flow and nutrient loads of a Mediterranean catchment in South Australia.

PubMed

Shrestha, Manoj K; Recknagel, Friedrich; Frizenschaf, Jacqueline; Meyer, Wayne

2017-07-15

Mediterranean catchments experience already high seasonal variability alternating between dry and wet periods, and are more vulnerable to future climate and land use changes. Quantification of catchment response under future changes is particularly crucial for better water resources management. This study assessed the combined effects of future climate and land use changes on water yield, total nitrogen (TN) and total phosphorus (TP) loads of the Mediterranean Onkaparinga catchment in South Australia by means of the eco-hydrological model SWAT. Six different global climate models (GCMs) under two representative concentration pathways (RCPs) and a hypothetical land use change were used for future simulations. The climate models suggested a high degree of uncertainty, varying seasonally, in both flow and nutrient loads; however, a decreasing trend was observed. Average monthly TN and TP load decreased up to -55% and -56% respectively and were found to be dependent on flow magnitude. The annual and seasonal water yield and nutrient loads may only slightly be affected by envisaged land uses, but significantly altered by intermediate and high emission scenarios, predominantly during the spring season. The combined scenarios indicated the possibility of declining flow in future but nutrient enrichment in summer months, originating mainly from the land use scenario, that may elevate the risk of algal blooms in downstream drinking water reservoir. Hence, careful planning of future water resources in a Mediterranean catchment requires the assessment of combined effects of multiple climate models and land use scenarios on both water quantity and quality. Copyright © 2017 Elsevier B.V. All rights reserved.

Forecasting Strategies for Predicting Peak Electric Load Days

NASA Astrophysics Data System (ADS)

Saxena, Harshit

Academic institutions spend thousands of dollars every month on their electric power consumption. Some of these institutions follow a demand charges pricing structure; here the amount a customer pays to the utility is decided based on the total energy consumed during the month, with an additional charge based on the highest average power load required by the customer over a moving window of time as decided by the utility. Therefore, it is crucial for these institutions to minimize the time periods where a high amount of electric load is demanded over a short duration of time. In order to reduce the peak loads and have more uniform energy consumption, it is imperative to predict when these peaks occur, so that appropriate mitigation strategies can be developed. The research work presented in this thesis has been conducted for Rochester Institute of Technology (RIT), where the demand charges are decided based on a 15 minute sliding window panned over the entire month. This case study makes use of different statistical and machine learning algorithms to develop a forecasting strategy for predicting the peak electric load days of the month. The proposed strategy was tested for a whole year starting May 2015 to April 2016 during which a total of 57 peak days were observed. The model predicted a total of 74 peak days during this period, 40 of these cases were true positives, hence achieving an accuracy level of 70 percent. The results obtained with the proposed forecasting strategy are promising and demonstrate an annual savings potential worth about $80,000 for a single submeter of RIT.

Unravelling the relative contribution of bed and suspended sediment load on a large alluvial river

NASA Astrophysics Data System (ADS)

Darby, S. E.; Hackney, C. R.; Parsons, D. R.; Leyland, J.; Aalto, R. E.; Nicholas, A. P.; Best, J.

2017-12-01

The world's largest rivers transport 19 billion tonnes of sediment to the coastal zone annually, often supporting large deltas that rely on this sediment load to maintain their elevation in the face of rising sea level, and to sustain high levels of agricultural productivity and biodiversity. However, the majority of estimates of sediment delivery to coastal regions pertain solely to the suspended fraction of the sediment load, with the bedload fraction often being neglected due to the difficulty in estimating bedload flux and the assumption that bedload contributes a minor (<10%) fraction of the total sediment load. In large rivers, capturing accurate estimates of the suspended- and bed- load fractions is difficult given the large channel widths and depths and the intrusive nature of typical methodologies. Yet, for the successful implementation of sustainable river, and delta, management plans, improved estimates of all fractions of the sediment load are essential. Recent advances in non-intrusive, high-resolution, technology have begun to enable more accurate estimates of bedload transport rates. However, the characterisation of the holistic sediment transport regime of large alluvial rivers is still lacking. Here, we develop a sediment transport rating curve, combining both suspended- and bed- load sediment fractions, for the Lower Mekong River. We define suspended sediment rating curves using the inversion of acoustic return data from a series of acoustic Doppler current profiler surveys conducted through the Lower Mekong River in Cambodia, and into the bifurcating channels of the Mekong delta in Vietnam. Additionally, we detail estimates of bed-load sediment transport determined using repeat multibeam echo sounder surveys of the channel bed. By combining estimates of both fractions of the sediment load, we show the spatial and temporal contribution of bedload to the total sediment load of the Mekong and refine estimates of sediment transport to the Mekong delta. Our results indicate that the time-averaged suspended load transport rates for the Mekong River are 87 MT/yr, whilst bedload transport forms c. < 5% of the total sediment load within the Mekong River. Such estimates are integral to future channel management within this highly threatened river basin.

[Simulation on area threshold of urban building land based on water environmental response in watersheds.

PubMed

He, Zhi Chao; Huang, Shuo; Guo, Qing Hai; Xiao, Li Shan; Yang, De Wei; Wang, Ying; Yang, Yi Fu

2016-08-01

Urban sprawl has impacted increasingly on water environment quality in watersheds. Based on water environmental response, the simulation and prediction of expanding threshold of urban building land could provide an alternative reference for urban construction planning. Taking three watersheds (i.e., Yundang Lake at complete urbanization phase, Maluan Bay at peri-urbanization phase and Xinglin Bay at early urbanization phase) with 2009-2012 observation data as example, we calculated the upper limit of TN and TP capacity in three watersheds and identified the threshold value of urban building land in watersheds using the regional nutrient management (ReNuMa) model, and also predicted the water environmental effects associated with the changes of urban landscape pattern. Results indicated that the upper limit value of TN was 12900, 42800 and 43120 kg, while that of TP was 340, 420 and 450 kg for Yundang, Maluan and Xinglin watershed, respectively. In reality, the environment capacity of pollutants in Yundang Lake was not yet satura-ted, and annual pollutant loads in Maluan Bay and Xinglin Bay were close to the upper limit. How-ever, an obvious upward trend of annual TN and TP loads was observed in Xinglin Bay. The annual pollutant load was not beyond the annual upper limit in three watersheds under Scenario 1, while performed oppositely under Scenario 3. Under Scenario 2, the annual pollutant load in Yundang Lake was under-saturation, and the TN and TP in Maluan Bay were over their limits. The area thresholds of urban building land were 1320, 5600 and 4750 hm 2 in Yundang Lake, Maluan Bay and Xinglin Bay, respectively. This study could benefit the regulation on urban landscape planning.

Possible correlation between annual gravity change and shallow background seismicity rate at subduction zone by surface load

NASA Astrophysics Data System (ADS)

Mitsui, Yuta; Yamada, Kyohei

2017-12-01

The Gravity Recovery and Climate Experiment (GRACE) has monitored global gravity changes since 2002. Gravity changes are considered to represent hydrological water mass movements around the surface of the globe, although fault slip of a large earthquake also causes perturbation of gravity. Since surface water movements are expected to affect earthquake occurrences via elastic surface load or pore-fluid pressure increase, correlation between gravity changes and occurrences of small (not large) earthquakes may reflect the effects of surface water movements. In the present study, we focus on earthquakes smaller than magnitude 7.5 and examine the relation between annual gravity changes and earthquake occurrences at worldwide subduction zones. First, we extract amplitudes of annual gravity changes from GRACE data for land. Next, we estimate background seismicity rates in the epidemic-type aftershock sequence model from shallow seismicity data having magnitudes of over 4.5. Then, we perform correlation analysis of the amplitudes of the annual gravity changes and the shallow background seismicity rates, excluding source areas of large earthquakes, and find moderate positive correlation. It implies that annual water movements can activate shallow earthquakes, although the surface load elastostatic stress changes are on the order of or below 1 kPa, as small as a regional case in a previous study. We speculate that periodic stress perturbation is amplified through nonlinear responses of frictional faults.[Figure not available: see fulltext.

Analysis of the solar radiation data for Beer Sheva, Israel, and its environs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kudish, A.I.; Ianetz, A.

The solar radiation climate of Beer Sheva, Israel, is reported upon in detail. The database utilized in this analysis consisted of global radiation on a horizontal surface, normal incidence beam radiation, and global radiation on a south-facing surface tilted at 40{degree}. Monthly-average hourly and daily values are reported for each of these three types of measured radiations, together with the calculated monthly-average daily values for the components of the global radiation, viz. the horizontal beam and diffuse radiations. The monthly-average hourly and daily clearness index values have also been calculated and analyzed. Monthly-average daily frequency distributions of the clearness indexmore » values are reported for each month. The solar radiation climate of Beer Sheva has also been compared to those reported for a number of countries in this region. The annual-average daily global radiation incident on a horizontal surface is 18.91 MG/m{sup 2} and that for normal incidence beam radiation is 21.17 MG/m{sup 2}. The annual-average daily fraction of the horizontal global radiation that is beam is 0.72. The annual-average daily value for the clearness index is 0.587 and the average frequency of clear days annually is 58.6%. The authors conclude, based upon the above analysis, that Beer Sheva and its environs are characterized by relatively high, average-daily irradiation rates, both global and beam, and a relatively high frequency of clear days.« less

Hydrology and water quality in 13 watersheds in Gwinnett County, Georgia, 2001–15

USGS Publications Warehouse

Aulenbach, Brent T.; Joiner, John K.; Painter, Jaime A.

2017-02-23

The U.S. Geological Survey (USGS), in cooperation with Gwinnett County Department of Water Resources, established a Long-Term Trend Monitoring (LTTM) program in 1996. The LTTM program is a comprehensive, long-term, water-quantity and water-quality monitoring program designed to document and analyze the hydrologic and water-quality conditions of selected watersheds in Gwinnett County, Georgia. Water-quality monitoring initially began in six watersheds and currently [2016] includes 13 watersheds.As part of the LTTM program, streamflow, precipitation, water temperature, specific conductance, and turbidity were measured every 15 minutes for water years 2001–15 at 12 of the 13 watershed monitoring stations and for water years 2010–15 at the other watershed. In addition, discrete water-quality samples were collected seasonally from May through October (summer) and November through April (winter), including one base-flow and three stormflow event composite samples, during the study period. Samples were analyzed for nutrients (nitrogen and phosphorus), total organic carbon, trace elements (total lead and total zinc), total dissolved solids, and total suspended sediment (total suspended solids and suspended-sediment concentrations). The sampling scheme was designed to identify variations in water quality both hydrologically and seasonally.The 13 watersheds were characterized for basin slope, population density, land use for 2012, and the percentage of impervious area from 2000 to 2014. Several droughts occurred during the study period—water years 2002, 2007–08, and 2011–12. Watersheds with the highest percentage of impervious areas had the highest runoff ratios, which is the portion of precipitation that occurs as runoff. Watershed base-flow indexes, the ratio of base-flow runoff to total runoff, were inversely correlated with watershed impervious area.Flood-frequency estimates were computed for 13 streamgages in the study area that have 10 or more years of annual peak flow data through water year 2015, using the expected moments algorithm to fit a Pearson Type III distribution to logarithms of annual peak flows. Kendall’s tau nonparametric test was used to determine the statistical significance of trends in the annual peak flows, with none of the 13 streamgages exhibiting significant trends.A comparison of base-flow and stormflow water-quality samples indicates that turbidity and concentrations of total ammonia plus organic nitrogen, total nitrogen, total phosphorus, total organic carbon, total lead, total zinc, total suspended solids, and suspended-sediment concentrations increased with increasing discharge at all watersheds. Specific conductance decreased during stormflow at all watersheds, and total dissolved solids concentrations decreased during stormflow at a few of the watersheds. Total suspended solids and suspended-sediment concentrations typically were two orders of magnitude higher in stormflow samples, turbidities were about 1.5 orders of magnitude higher, total phosphorus and total zinc were about one order of magnitude higher, and total ammonia plus organic nitrogen, total nitrogen, total organic carbon, and total lead were about twofold higher than in base-flow samples.Seasonality and long-term trends were identified for the period water years 2001–15 for 10 constituents—total nitrogen, total nitrate plus nitrite, total phosphorus, dissolved phosphorus, total organic carbon, total suspended solids, suspended-sediment concentration, total lead, total zinc, and total dissolved solids. Seasonal patterns were present in most watersheds for all constituents except total dissolved solids, and the watersheds had fairly similar patterns of higher concentrations in the summer and lower concentrations in the winter. A linear long-term trend analysis of residual concentrations from the flow-only load estimation model (without time-trend terms) identified significant trends in 67 of the 130 constituent-watershed combinations. Seventy percent of the significant trends were negative. Total organic carbon and total dissolved solids had predominantly positive trends. Total phosphorus, total suspended solids, suspended-sediment concentration, total lead, and total zinc had only negative trends. The other three constituents exhibited fewer trends, both positive and negative.Streamwater loads were estimated annually for the 13-year period water years 2003–15 for the same 10 constituents in the trend analysis. Loads were estimated using a regression-model-based approach developed by the USGS for the Gwinnett County LTTM program that accommodates the use of storm-event composited samples. Concentrations were modeled as a function of discharge, base flow, time, season, and turbidity to improve model predictions and reduce errors in load estimates. Total suspended solids annual loads have been identified in Gwinnett County’s Watershed Protection Plan for target performance criterion.Although the amount of annual runoff was the primary factor in variations in annual loads, climatic conditions (classified as dry, average, or wet) affected annual loads beyond what was attributed to climatic-related variations in annual runoff. Significant negative trends in loads were estimated for the combined area of the watersheds for all constituents except dissolved phosphorus, total organic carbon, and total dissolved solids. The trend analysis indicated that total suspended solids and suspended-sediment concentration loads in the study area were decreasing by 57,000 and 87,000 pounds per day per year, respectively.Variations in constituent yields between watersheds appeared to be related to various watershed characteristics. Suspended sediment (as either total suspended solids or suspended-sediment concentrations), along with constituents transported predominately in solid phase (total phosphorus, total organic carbon, total lead, and total zinc), and total dissolved solids typically had higher yields from watersheds that had high percentages of impervious areas or high basin slope. High total nitrogen yields were also associated with watersheds with high percentages of impervious areas. Low total nitrogen, total suspended solids, total lead, and total zinc yields appeared to be associated with watersheds that had a low percentage of high-density development.

Design test request No. 1263 K Reactor graphite key and VSR channel sleeve test

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kempf, F.J.

1964-12-10

The objectives of this test were: (1) Determine the coefficient of friction between two adjacent layers of K Reactor graphite at room temperature. (2) Determine the average load required to cause failure of an unirradiated K Reactor side reflector bar, when subjected to tensile loading applied through the reflector keys. (3) Determine the average load at failure and the average deflection at failure of a single VSR channel key when loaded in keyways with clearances equal to those used in original stack construction. (4) Determine the average load and deflection required to break the four K Reactor VSR keys whenmore » loaded simultaneously in both `3-layer` and `7-layer` mockups. Also determine the mode of key failure; i.e., shear, flexure or combined compression and bending. Following these key rupture tests, determine the strength and deflection characteristics of the proposed K Reactor VSR channel sleeve when loaded in a manner identical to that used to fracture the keys. (5) Determine the average load and deflection at failure of both the proposed K Reactor VSR channel sleeves and the proposed C Reactor sleeves when subjected to crushing loads. (6) Determine the extent of damage to the proposed K Reactor VSR channel sleeve when subjected to the following vertical rod loading conditions. (a) Full rod drop in a channel mockup which has been misaligned 2 1/2 inches. (b) Full rod drop in a channel which has been misaligned an amount equal to the maximum flexibility of a `universal` VSR.« less

Subsurface recharge to the Tesuque aquifer system from selected drainage basins along the western side of the Sangre de Cristo Mountains near Santa Fe, New Mexico

USGS Publications Warehouse

Wasiolek, Maryann

1995-01-01

Water budgets developed for basins of five streams draining the western side of the Sangre de Cristo Mountains in northern New Mexico indicate that subsurface inflow along the mountain front is recharging the Tesuque aquifer system of the Espanola Basin. Approximately 14,700 acre-feet of water per year, or 12.7 percent of average annual precipitation over the mountains, is calculated to leave the mountain block and enter the basin as subsurface recharge from the drainage basins of the Rio Nambe, Rio en Medio, Tesuque Creek, Little Tesuque Creek, and Santa Fe River. About 5,520 acre- feet per year, or about 12 percent of average annual precipitation, is calculated to enter from the Rio Nambe drainage basin; about 1,710 acre- feet per year, or about 15 percent of average annual precipitation, is calculated to enter from the Rio en Medio drainage basin; about 1,530 acre- feet, or about 10 percent of average annual precipi- tation, is calculated to enter from the Tesuque Creek drainage basin; about 1,790 acre-feet, or about 19 percent of average annual precipitation, is calculated to enter from the Little Tesuque Creek drainage basin; and about 4,170 acre-feet per year, or about 12 percent average annual precipitation, is calculated to enter from the Santa Fe River drainage basin. Calculated subsurface recharge values were used to define maximum fluxes permitted along the specified-flux boundary defining the mountain front of the Sangre De Cristo Mountains in a numerical computer model of the Tesuque aquifer system near Santa Fe, New Mexico.

Water-quality characteristics in runoff for three discovery farms in North Dakota, 2008-12

USGS Publications Warehouse

Nustad, Rochelle A.; Rowland, Kathleen M.; Wiederholt, Ronald

2015-01-01

Consistent patterns in water quality emerged at each individual farm, but similarities among farms also were observed. Suspended sediment, total phosphorus, and ammonia concentrations generally decreased downstream from feeding areas, and were primarily affected by surface runoff processes such as dilution, settling out of sediment, or vegetative uptake. Because surface runoff affects these constituents, increased annual surface runoff volume tended to result in increased loads and yields. No significant change in nitrate plus nitrite concentration were observed downstream from feeding areas because additional processes such as high solubility, nitrification, denitrification, and surface-groundwater interaction affect nitrate plus nitrite. For nitrate plus nitrite, increases in annual runoff volume did not consistently relate to increases in annual loads and yields. It seems that temporal distribution of precipitation and surface-groundwater interaction affected nitrate plus nitrite loads and yields. For surface drainage sites, the primary form of nitrogen was organic nitrogen whereas for subsurface drainage sites, the primary form of nitrogen was nitrate plus nitrite nitrogen.

77 FR 14366 - Notice of Annual Adjustment of the Cap on Average Total Assets That Defines Community Financial...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-09

... FEDERAL HOUSING FINANCE AGENCY [No. 2012-N-02] Notice of Annual Adjustment of the Cap on Average.... ACTION: Notice. SUMMARY: The Federal Housing Finance Agency (FHFA) has adjusted the cap on average total... statutory cap.\\2\\ The Bank Act was amended in 2008 to set the statutory cap at $1 billion and to require the...

Water quality in the St. Croix National Scenic Riverway, Wisconsin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Graczyk, D.J.

1986-01-01

A water quality study of the St. Croix National Scenic Riverway, was conducted during the period 1975-83. Concentrations of most constituents analyzed, and constituent loads and yields were lower in the Scenic Riverway than in other Wisconsin streams. Water quality samples were collected at 10 stations throughout the study area and were compared to analyses of samples from selected National Stream Quality Accounting Network stations (NASWAN) and the Hydrologic Bench-Mark Network (HBMN) station in Wisconsin. The average suspended sediment (SS) concentration for 9 of the 10 stations in this study was 7.7 mg/L. The concentrations of major cations and anionsmore » at two of the stations were similar to concentrations at the HBMN station Popple River near Fence. Mean total phosphorus concentrations ranged from 0.02 to 0.08 mg/L at the study stations and from 0.03 to 0.16 mg/L at selected NASQAN stations. Concentrations of trace metals were below safe drinking water standards at all the study sites, except for iron and manganese which exceeded drinking water standards at some of the study sites. Pesticides were sampled at the St. Croix River at St. Croix Falls and above and below cranberry bogs that drain into the Namekagon River. Average annual loads of SS, total phosphorus, total nitrogen, and dissolved solids were calculated by a flow duration curve method. Suspended sediment yields ranged from 1.9 to 13.3 tons/sq mi. The average SS yield for Wisconsin is 80 tons/sq mi. total phosphorus and other constituents exhibited the same trend. 26 refs., 10 figs., 12 tabs.« less

75 FR 71446 - Agency Information Collection Activities; Proposed Collection; Comment Request; Reports of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-23

... information regarding these corrections and removals and to determine whether recall action is adequate... Annual Reporting Burden\\1\\ Annual 21 CFR section Number of frequency per Total annual Hours per Total... Average Annual Recordkeeping Burden \\1\\ Annual 21 CFR Section Number of frequency per Total annual Hours...

An urban runoff model designed to inform stormwater management decisions.

PubMed

Beck, Nicole G; Conley, Gary; Kanner, Lisa; Mathias, Margaret

2017-05-15

We present an urban runoff model designed for stormwater managers to quantify runoff reduction benefits of mitigation actions that has lower input data and user expertise requirements than most commonly used models. The stormwater tool to estimate load reductions (TELR) employs a semi-distributed approach, where landscape characteristics and process representation are spatially-lumped within urban catchments on the order of 100 acres (40 ha). Hydrologic computations use a set of metrics that describe a 30-year rainfall distribution, combined with well-tested algorithms for rainfall-runoff transformation and routing to generate average annual runoff estimates for each catchment. User inputs include the locations and specifications for a range of structural best management practice (BMP) types. The model was tested in a set of urban catchments within the Lake Tahoe Basin of California, USA, where modeled annual flows matched that of the observed flows within 18% relative error for 5 of the 6 catchments and had good regional performance for a suite of performance metrics. Comparisons with continuous simulation models showed an average of 3% difference from TELR predicted runoff for a range of hypothetical urban catchments. The model usually identified the dominant BMP outflow components within 5% relative error of event-based measured flow data and simulated the correct proportionality between outflow components. TELR has been implemented as a web-based platform for use by municipal stormwater managers to inform prioritization, report program benefits and meet regulatory reporting requirements (www.swtelr.com). Copyright © 2017. Published by Elsevier Ltd.

Sources and Trends of Nitrogen Loading to New England Estuaries

EPA Science Inventory

A database of nitrogen (N) loading components to estuaries of the conterminous United States has been developed through application of regional SPARROW models. The original SPARROW models predict average detrended loads by source based on average flow conditions and 2002 source t...

Medical expenditures in division I collegiate athletics: an analysis by sport and gender.

PubMed

Kaeding, Christopher C; Borchers, James; Oman, Janine; Pedroza, Angela

2014-09-01

Medical expenses for collegiate athletics include providing a training room with its supplies, equipment, personnel costs, and insurance coverage. Additional expenses beyond the training room include imaging, diagnostic testing, specialty consultations, and surgeries. We hypothesized that there would be no difference in average expenses or number of claims between male and female athletes over a 5-year period. Prospective patient cohort. A sports medicine center serving athletes in Big 10 Conference intercollegiate sports. All medical claims and charges for 36 varsity teams were analyzed from 2005 to 2010. The teams were categorized into 3 groups: female-only teams, male-only teams, and coed teams. Analysis of sports with corresponding male and female teams was also performed. Claims and charges for medical care for 36 intercollegiate athletic teams over 5 years. Individual team claims and charges were stable over the study period. In 11 of the 14 sex-matched sports, the female teams had higher average annual charges. After normalizing for roster size in the sex-matched sports, females had 0.97 more average annual claims (P < 0.01) and $1459 higher annual charges (P = 0.001) than their male counterparts. The charges per claim were similar between the sexes. The 5 teams with the highest average annual charges were football, wrestling, softball, women's crew, and men's lacrosse. When normalized for roster size, the 5 sports with the highest average annual charges per athlete were softball, women's diving, men's basketball, wrestling, and men's gymnastics. Charges per claim were similar between the sex-matched sports, but the female sports had a higher number of annual claims per athlete and thus higher total charges per athlete/year. Football had the highest average annual total charges as a team, but when normalized for roster size football charges per athlete/year were similar to those of other sports.

Suspended-Sediment Budget for the North Santiam River Basin, Oregon, Water Years 2005-08

USGS Publications Warehouse

Bragg, Heather M.; Uhrich, Mark A.

2010-01-01

Significant Findings An analysis of sediment transport in the North Santiam River basin during water years 2005-08 indicated that: Two-thirds of sediment input to Detroit Lake originated in the upper North Santiam River subbasin. Two-thirds of the sediment transported past Geren Island originated in the Little North Santiam River subbasin. The highest annual suspended-sediment load at any of the monitoring stations was the result of a debris flow on November 6, 2006, on Mount Jefferson. About 86 percent of the total sediment input to Detroit Lake was trapped in the lake, whereas 14 percent was transported farther downstream. More than 80 percent of the sediment transport in the basin was in November, December, and January. The variance in the annual suspended-sediment loads was better explained by the magnitude of the annual peak streamflow than by the annual mean streamflow.

40 CFR 80.90 - Conventional gasoline baseline emissions determination.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Conventional gasoline baseline... gasoline baseline emissions determination. (a) Annual average baseline values. For any facility of a refiner or importer of conventional gasoline, the annual average baseline values of the facility's exhaust...

40 CFR 80.90 - Conventional gasoline baseline emissions determination.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Conventional gasoline baseline... gasoline baseline emissions determination. (a) Annual average baseline values. For any facility of a refiner or importer of conventional gasoline, the annual average baseline values of the facility's exhaust...

40 CFR 80.90 - Conventional gasoline baseline emissions determination.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Conventional gasoline baseline... gasoline baseline emissions determination. (a) Annual average baseline values. For any facility of a refiner or importer of conventional gasoline, the annual average baseline values of the facility's exhaust...

40 CFR 80.90 - Conventional gasoline baseline emissions determination.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Conventional gasoline baseline... gasoline baseline emissions determination. (a) Annual average baseline values. For any facility of a refiner or importer of conventional gasoline, the annual average baseline values of the facility's exhaust...

40 CFR 80.90 - Conventional gasoline baseline emissions determination.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Conventional gasoline baseline... gasoline baseline emissions determination. (a) Annual average baseline values. For any facility of a refiner or importer of conventional gasoline, the annual average baseline values of the facility's exhaust...

Acid rain monitoring in East-Central Florida from 1977 to present

NASA Technical Reports Server (NTRS)

Madsen, B. C.; Kheoh, T.; Hinkle, C. R.; Dreschel, T. W.

1990-01-01

Rainfall has been collected on the University of Central Florida campus and at the Kennedy Space Center over a 12 year period. The chemical composition has been determined and summarized by monthly, annual periods, and for the entire 12 year period at both locations. The weighted average pH at each site is 4.58; however, annual weighted average pH has been equal to or above the 12 year average during six of the past eight years. Nitrate concentrations have increased slightly during recent years while excess sulfate concentrations have remained below the 12 year weighted average during six of the past seven years. Stepwise regression suggests that sulfate, nitrate, ammonium ion and calcium play major roles in the description of rainwater acidity. Annual acid deposition and annual rainfall have varied from 20 to 50 meg/(m(exp 2) year) and 100 to 180 cm/year, respectively. Sea salt comprises at least 25 percent of the total ionic composition.

Water Quality, Hydrology, and Simulated Response to Changes in Phosphorus Loading of Butternut Lake, Price and Ashland Counties, Wisconsin, with Special Emphasis on the Effects of Internal Phosphorus Loading in a Polymictic Lake

USGS Publications Warehouse

Robertson, Dale M.; Rose, William J.

2008-01-01

Butternut Lake is a 393-hectare, eutrophic to hypereutrophic lake in northcentral Wisconsin. After only minor improvements in water quality were observed following several actions taken to reduce the nutrient inputs to the lake, a detailed study was conducted from 2002 to 2007 by the U.S. Geological Survey to better understand how the lake functions. The goals of this study were to describe the water quality and hydrology of the lake, quantify external and internal sources of phosphorus, and determine the effects of past and future changes in phosphorus inputs on the water quality of the lake. Since the early 1970s, the water quality of Butternut Lake has changed little in response to nutrient reductions from the watershed. The largest changes were in near-surface total phosphorus concentrations: August concentrations decreased from about 0.09 milligrams per liter (mg/L) to about 0.05 mg/L, but average summer concentrations decreased only from about 0.055-0.060 mg/L to about 0.045 mg/L. Since the early 1970s, only small changes were observed in chlorophyll a concentrations and water clarity (Secchi depths). All major water and phosphorus sources, including the internal release of phosphorus from the sediments (internal loading), were measured directly, and minor sources were estimated to construct detailed water and phosphorus budgets for the lake during monitoring years (MY) 2003 and 2004. During these years, Butternut Creek, Spiller Creek, direct precipitation, small tributaries and near-lake drainage area, and ground water contributed about 62, 20, 8, 7, and 3 percent of the inflow, respectively. The average annual load of phosphorus to the lake was 2,540 kilograms (kg), of which 1,590 kg came from external sources (63 percent) and 945 kg came from the sediments in the lake (37 percent). Of the total external sources, Butternut Creek, Spiller Creek, small tributaries and near-lake drainage area, septic systems, precipitation, and ground water contributed about 63, 23, 9, 3, 1, and 1 percent, respectively. Because of the high internal phosphorus loading, the eutrophication models used in this study were unable to simulate the observed water-quality characteristics in the lake without incorporating this source of phosphorus. However, when internal loading of phosphorus was added to the BATHTUB model, it accurately simulated the average water-quality characteristics measured in MY 2003 and 2004. Model simulations demonstrated a relatively linear response between in-lake total phosphorus concentrations and external phosphorus loading; however, the changes in concentrations were smaller than the changes in external phosphorus loadings (about 25-40 percent of the change in phosphorus loading). Changes in chlorophyll a concentrations, the percentage of days with algal blooms, and Secchi depths were nonlinear and had a greater response to reductions in phosphorus loading than to increases in phosphorus loading. A 50-percent reduction in external phosphorus loading caused an 18-percent decrease in chlorophyll a concentrations, a 41-percent decrease in the percentage of days with algal blooms, and a 12-percent increase in Secchi depth. When the additional internal phosphorus loading was removed from model simulations, all of these constituents showed a much greater response to changes in external phosphorus loading. Because of Butternut Lake's morphometry, it is polymictic, which means it mixes frequently and does not develop stable thermal stratification throughout the summer. This characteristic makes it more vulnerable than dimictic lakes, which mix in spring and fall and develop stable thermal stratification during summer, to the high internal phosphorus loading that has resulted from historically high, nonnatural, external phosphorus loading. In polymictic lakes, the phosphorus released from the sediments is mixed into the upper part of the lake throughout summer. Once Butternut Lake became hypereutrophic (very p

Annual modulation of non-volcanic tremor in northern Cascadia

USGS Publications Warehouse

Pollitz, Fred; Wech, Aaron G.; Kao, Honn; Burgmann, Roland

2013-01-01

Two catalogs of episodic tremor events in northern Cascadia, one from 2006 to 2012 and the other from 1997 to 2011, reveal two systematic patterns of tremor occurrence in southern Vancouver Island: (1) most individual events tend to occur in the third quarter of the year; (2) the number of events in prolonged episodes (i.e., episodic tremor and slip events), which generally propagate to Vancouver Island from elsewhere along the Cascadia subduction zone, is inversely correlated with the amount of precipitation that occurred in the preceding 2 months. We rationalize these patterns as the product of hydrologic loading of the crust of southern Vancouver Island and the surrounding continental region, superimposed with annual variations from oceanic tidal loading. Loading of the Vancouver Island crust in the winter (when the land surface receives ample precipitation) and unloading in the summer tends to inhibit and enhance downdip shear stress, respectively. Quantitatively, for an annually variable surface load, the predicted stress perturbation depends on mantle viscoelastic rheology. A mechanical model of downdip shear stress on the transition zone beneath Vancouver Island—driven predominantly by the annual hydrologic cycle—is consistent with the 1997–2012 tremor observations, with peak-to-peak downdip shear stress of about 0.4 kPa. This seasonal dependence of tremor occurrence appears to be restricted to southern Vancouver Island because of its unique situation as an elongated narrow-width land mass surrounded by ocean, which permits seasonal perturbations in shear stress at depth.

Climate change impacts on forest soil critical acid loads and exceedances at a national scale

Treesearch

Steven G. McNulty; Erika C. Cohen; Jennifer A. Moore Myers

2013-01-01

Federal agencies are currently developing guidelines for forest soil critical acid loads across the United States. A critical acid load is defined as the amount of acid deposition (usually expressed on an annual basis) that an ecosystem can absorb. Traditionally, an ecosystem is considered to be at risk for health impairment when the critical acid load exceeds a level...

The value of point-of-care CD4+ and laboratory viral load in tailoring antiretroviral therapy monitoring strategies to resource limitations.

PubMed

Hyle, Emily P; Jani, Ilesh V; Rosettie, Katherine L; Wood, Robin; Osher, Benjamin; Resch, Stephen; Pei, Pamela P; Maggiore, Paolo; Freedberg, Kenneth A; Peter, Trevor; Parker, Robert A; Walensky, Rochelle P

2017-09-24

To examine the clinical and economic value of point-of-care CD4 (POC-CD4) or viral load monitoring compared with current practices in Mozambique, a country representative of the diverse resource limitations encountered by HIV treatment programs in sub-Saharan Africa. We use the Cost-Effectiveness of Preventing AIDS Complications-International model to examine the clinical impact, cost (2014 US$), and incremental cost-effectiveness ratio [$/year of life saved (YLS)] of ART monitoring strategies in Mozambique. We compare: monitoring for clinical disease progression [clinical ART monitoring strategy (CLIN)] vs. annual POC-CD4 in rural settings without laboratory services and biannual laboratory CD4 (LAB-CD4), biannual POC-CD4, and annual viral load in urban settings with laboratory services. We examine the impact of a range of values in sensitivity analyses, using Mozambique's 2014 per capita gross domestic product ($620) as a benchmark cost-effectiveness threshold. In rural settings, annual POC-CD4 compared to CLIN improves life expectancy by 2.8 years, reduces time on failed ART by 0.6 years, and yields an incremental cost-effectiveness ratio of $480/YLS. In urban settings, biannual POC-CD4 is more expensive and less effective than viral load. Compared to biannual LAB-CD4, viral load improves life expectancy by 0.6 years, reduces time on failed ART by 1.0 year, and is cost-effective ($440/YLS). In rural settings, annual POC-CD4 improves clinical outcomes and is cost-effective compared to CLIN. In urban settings, viral load has the greatest clinical benefit and is cost-effective compared to biannual POC-CD4 or LAB-CD4. Tailoring ART monitoring strategies to specific settings with different available resources can improve clinical outcomes while remaining economically efficient.

The role of baseflow in dissolved solids delivery to streams in the Upper Colorado River Basin

NASA Astrophysics Data System (ADS)

Rumsey, C.; Miller, M. P.; Schwarz, G. E.; Susong, D.

2017-12-01

Salinity has a major effect on water users in the Colorado River Basin, estimated to cause almost $300 million per year in economic damages. The Colorado River Basin Salinity Control Program implements and manages projects to reduce salinity (dissolved solids) loads, investing millions of dollars per year in irrigation upgrades, canal projects, and other mitigation strategies. To inform and improve mitigation efforts, there is a need to better understand sources of salinity to streams and how salinity has changed over time. This study explores salinity in baseflow, or groundwater discharge to streams, to assess whether groundwater is a significant contributor of dissolved solids to streams in the Upper Colorado River Basin (UCRB). Chemical hydrograph separation was used to estimate long-term mean annual baseflow discharge and baseflow dissolved solids loads at stream gages (n=69) across the UCRB. On average, it is estimated that 89% of dissolved solids loads originate from the baseflow fraction of streamflow. Additionally, a statistical trend analysis using weighted regressions on time, discharge, and season was used to evaluate changes in baseflow dissolved solids loads in streams with data from 1987 to 2011 (n=29). About two-thirds (62%) of these streams showed statistically significant decreasing trends in baseflow dissolved solids loads. At the two most downstream sites, Green River at Green River, UT and Colorado River at Cisco, UT, baseflow dissolved solids loads decreased by a combined 780,000 metric tons, which is approximately 65% of the estimated basin-scale decrease in total dissolved solids loads in the UCRB attributed to salinity control efforts. Results indicate that groundwater discharged to streams, and therefore subsurface transport processes, play a large role in delivering dissolved solids to streams in the UCRB. Decreasing trends in baseflow dissolved solids loads suggest that salinity mitigation projects, changes in land use, and/or climate are decreasing salinity in groundwater transported to streams.

Biomechanical evaluation of fracture fixation constructs using a variable-angle locked periprosthetic femur plate system.

PubMed

Hoffmann, Martin F; Burgers, Travis A; Mason, James J; Williams, Bart O; Sietsema, Debra L; Jones, Clifford B

2014-07-01

In the United States there are more than 230,000 total hip replacements annually, and periprosthetic femoral fractures occur in 0.1-4.5% of those patients. The majority of these fractures occur at the tip of the stem (Vancouver type B1). The purpose of this study was to compare the biomechanically stability and strength of three fixation constructs and identify the most desirable construct. Fifteen medium adult synthetic femurs were implanted with a hip prosthesis and were osteotomized in an oblique plane at the level of the implant tip to simulate a Vancouver type B1 periprosthetic fracture. Fractures were fixed with a non-contact bridging periprosthetic proximal femur plate (Zimmer Inc., Warsaw, IN). Three proximal fixation methods were used: Group 1, bicortical screws; Group 2, unicortical screws and one cerclage cable; and Group 3, three cerclage cables. Distally, all groups had bicortical screws. Biomechanical testing was performed using an axial-torsional testing machine in three different loading modalities (axial compression, lateral bending, and torsional/sagittal bending), next in axial cyclic loading to 10,000 cycles, again in the three loading modalities, and finally to failure in torsional/sagittal bending. Group 1 had significantly greater load to failure and was significantly stiffer in torsional/sagittal bending than Groups 2 and 3. After cyclic loading, Group 2 had significantly greater axial stiffness than Groups 1 and 3. There was no difference between the three groups in lateral bending stiffness. The average energy absorbed during cyclic loading was significantly lower in Group 2 than in Groups 1 and 3. Bicortical screw placement achieved the highest load to failure and the highest torsional/sagittal bending stiffness. Additional unicortical screws improved axial stiffness when using cable fixation. Lateral bending was not influenced by differences in proximal fixation. To treat periprosthetic fractures, bicortical screw placement should be attempted to maximize load to failure and torsional/sagittal bending stiffness. Copyright © 2014 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, L.L.; Hooper, M.

This report summarizes the activities and results for the second testing phase (Phase 2) of an Innovative Clean Coal Technology (ICCT) demonstration of advanced tangentially fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. All three levels of Asea Brown Boveri Combustion Engineering Service`s (ABB CE`s) Low-NO{sub x} Concentric Firing System (LNCFS) are being demonstrated during this project. The primary goal of this project is to demonstrate the NO{sub x} emissions characteristics of these technologies when operated under normal load dispatched conditions. The equipment is being tested at Gulf Power Company`s Plant Lansing Smith Unitmore » 2 in Lynn Haven, Florida. The long-term NO{sub x} emission trends were documented while the unit was operating under normal load dispatch conditions with the LNCFS Level II equipment. Fifty-five days of long-term data were collected. The data included the effects of mill patterns, unit load, mill outages, weather, fuel variability, and load swings. Test results indicated full-load (180 MW) NO{sub x} emissions of 0.39 lb/MBtu, which is about equal to the short-term test results. At 110 MW, long-term NO{sub x} emissions increased to 0.42 lb/MBtu, which are slightly higher than the short-term data. At 75 MW, NO{sub x} emissions were 0.51 lb/MBtu, which is significantly higher than the short-term data. The annual and 30-day average achievable NOx emissions were determined to be 0.41 and 0.45 lb/MBtu, respectively, for long-term testing load scenarios. NO{sub x} emissions were reduced by a maximum of 40 percent when compared to the baseline data collected in the previous phase. The long-term NO{sub x} reduction at full load (180 MW) was 37 percent while NO{sub x} reduction at low load was minimal.« less

Short-term response of the solid Earth to cryosphere fluctuations and the earthquake cycle in south-central Alaska

NASA Astrophysics Data System (ADS)

Sauber, J. M.; Freymueller, J. T.; Han, S. C.; Davis, J. L.; Ruppert, N. A.

2016-12-01

In southern Alaska surface deformation and gravimetric change are associated with the seismic cycle as well as a strong seasonal cycle of snow accumulation and melt and a variable rate of glacier mass wastage. Numerical modeling of the solid Earth response to cryosphere change on a variety of temporal and spatial scales plays a critical role in supporting the interpretation of time-variable gravity and other geodetic data. In this study we calculate the surface displacements and stresses associated with variable spatial and temporal cryospheric loading and unloading in south-central coastal Alaska. A challenging aspect of estimating the response of the solid Earth to short-term (months to 102 years) regional cryospheric fluctuations is choosing the rock mechanics constitutive laws appropriate to this region. Here we report calculated differences in the predicted surface displacements and stresses during the GRACE time period (2002 to present). Broad-scale, GRACE-derived estimates of cryospheric mass change, along with independent snow melt onset/refreeze timing, snow depth and annual glacier wastage estimates from a variety of methods, were used to approximate the magnitude and timing of cryospheric load changes. We used the CIG finite element code PyLith to enable input of spatially complex surface loads. An as example of our evaluation of the influence of variable short-term surface loads, we calculated and contrasted the predicted surface displacements and stresses for a cooler than average and higher precipitation water year (WY12) versus a warmer than average year (WY05). Our calculation of these comparative stresses is motivated by our earlier empirical evaluation of the influence of short-term cryospheric fluctuations on the background seismic rate between 1988-2006 (Sauber and Ruppert, 2008). During the warmer than average years between 2002-2006 we found a stronger seasonal dependency in the frequency of small tectonic events in the Icy Bay region relative to cooler years. To date, we have focused our 3-D modeling on changes in the thickness of the primarily elastic layer and we also varied the Maxwell viscoelastic relaxation times for the lower crust and upper mantle. We anticipate exploring the influence of transient rheologies and testing alternate 3-D rheological structures.

Sulfur deposition simulations over China, Japan, and Korea: a model intercomparison study for abating sulfur emission.

PubMed

Kim, Cheol-Hee; Chang, Lim-Seok; Meng, Fan; Kajino, Mizuo; Ueda, Hiromasa; Zhang, Yuanhang; Son, Hye-Young; Lee, Jong-Jae; He, Youjiang; Xu, Jun; Sato, Keiichi; Sakurai, Tatsuya; Han, Zhiwei; Duan, Lei; Kim, Jeong-Soo; Lee, Suk-Jo; Song, Chang-Keun; Ban, Soo-Jin; Shim, Shang-Gyoo; Sunwoo, Young; Lee, Tae-Young

2012-11-01

In response to increasing trends in sulfur deposition in Northeast Asia, three countries in the region (China, Japan, and Korea) agreed to devise abatement strategies. The concepts of critical loads and source-receptor (S-R) relationships provide guidance for formulating such strategies. Based on the Long-range Transboundary Air Pollutants in Northeast Asia (LTP) project, this study analyzes sulfur deposition data in order to optimize acidic loads over the three countries. The three groups involved in this study carried out a full year (2002) of sulfur deposition modeling over the geographic region spanning the three countries, using three air quality models: MM5-CMAQ, MM5-RAQM, and RAMS-CADM, employed by Chinese, Japanese, and Korean modeling groups, respectively. Each model employed its own meteorological numerical model and model parameters. Only the emission rates for SO(2) and NO(x) obtained from the LTP project were the common parameter used in the three models. Three models revealed some bias from dry to wet deposition, particularly the latter because of the bias in annual precipitation. This finding points to the need for further sensitivity tests of the wet removal rates in association with underlying cloud-precipitation physics and parameterizations. Despite this bias, the annual total (dry plus wet) sulfur deposition predicted by the models were surprisingly very similar. The ensemble average annual total deposition was 7,203.6 ± 370 kt S with a minimal mean fractional error (MFE) of 8.95 ± 5.24 % and a pattern correlation (PC) of 0.89-0.93 between the models. This exercise revealed that despite rather poor error scores in comparison with observations, these consistent total deposition values across the three models, based on LTP group's input data assumptions, suggest a plausible S-R relationship that can be applied to the next task of designing cost-effective emission abatement strategies.

Climate, soil water storage, and the average annual water balance

USGS Publications Warehouse

Milly, P.C.D.

1994-01-01

This paper describes the development and testing of the hypothesis that the long-term water balance is determined only by the local interaction of fluctuating water supply (precipitation) and demand (potential evapotranspiration), mediated by water storage in the soil. Adoption of this hypothesis, together with idealized representations of relevant input variabilities in time and space, yields a simple model of the water balance of a finite area having a uniform climate. The partitioning of average annual precipitation into evapotranspiration and runoff depends on seven dimensionless numbers: the ratio of average annual potential evapotranspiration to average annual precipitation (index of dryness); the ratio of the spatial average plant-available water-holding capacity of the soil to the annual average precipitation amount; the mean number of precipitation events per year; the shape parameter of the gamma distribution describing spatial variability of storage capacity; and simple measures of the seasonality of mean precipitation intensity, storm arrival rate, and potential evapotranspiration. The hypothesis is tested in an application of the model to the United States east of the Rocky Mountains, with no calibration. Study area averages of runoff and evapotranspiration, based on observations, are 263 mm and 728 mm, respectively; the model yields corresponding estimates of 250 mm and 741 mm, respectively, and explains 88% of the geographical variance of observed runoff within the study region. The differences between modeled and observed runoff can be explained by uncertainties in the model inputs and in the observed runoff. In the humid (index of dryness <1) parts of the study area, the dominant factor producing runoff is the excess of annual precipitation over annual potential evapotranspiration, but runoff caused by variability of supply and demand over time is also significant; in the arid (index of dryness >1) parts, all of the runoff is caused by variability of forcing over time. Contributions to model runoff attributable to small-scale spatial variability of storage capacity are insignificant throughout the study area. The consistency of the model with observational data is supportive of the supply-demand-storage hypothesis, which neglects infiltration excess runoff and other finite-permeability effects on the soil water balance.

Uncertainty in nutrient loads from tile drained landscapes: Effect of sampling frequency, calculation algorithm, and compositing strategies

USDA-ARS?s Scientific Manuscript database

Accurate estimates of annual nutrient loads are required to evaluate trends in water quality following changes in land use or management and to calibrate and validate water quality models. While much emphasis has been placed on understanding the uncertainty of watershed-scale nutrient load estimates...

Module failure isolation circuit for paralleled inverters. [preventing system failure during power conditioning for spacecraft applications

NASA Technical Reports Server (NTRS)

Nagano, S. (Inventor)

1979-01-01

A module failure isolation circuit is described which senses and averages the collector current of each paralled inverter power transistor and compares the collector current of each power transistor the average collector current of all power transistors to determine when the sensed collector current of a power transistor in any one inverter falls below a predetermined ratio of the average collector current. The module associated with any transistor that fails to maintain a current level above the predetermined radio of the average collector current is then shut off. A separate circuit detects when there is no load, or a light load, to inhibit operation of the isolation circuit during no load or light load conditions.

Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed

USGS Publications Warehouse

Brakebill, John W.; Preston, Stephen D.

1999-01-01

Digital data sets were compiled by the U. S. Geological Survey (USGS) and used as input for a collection of Spatially Referenced Regressions On Watershed attributes for the Chesapeake Bay region. These regressions relate streamwater loads to nutrient sources and the factors that affect the transport of these nutrients throughout the watershed. A digital segmented network based on watershed boundaries serves as the primary foundation for spatially referencing total nitrogen and total phosphorus source and land-surface characteristic data sets within a Geographic Information System. Digital data sets of atmospheric wet deposition of nitrate, point-source discharge locations, land cover, and agricultural sources such as fertilizer and manure were created and compiled from numerous sources and represent nitrogen and phosphorus inputs. Some land-surface characteristics representing factors that affect the transport of nutrients include land use, land cover, average annual precipitation and temperature, slope, and soil permeability. Nutrient input and land-surface characteristic data sets merged with the segmented watershed network provide the spatial detail by watershed segment required by the models. Nutrient stream loads were estimated for total nitrogen, total phosphorus, nitrate/nitrite, amonium, phosphate, and total suspended soilds at as many as 109 sites within the Chesapeake Bay watershed. The total nitrogen and total phosphorus load estimates are the dependent variables for the regressions and were used for model calibration. Other nutrient-load estimates may be used for calibration in future applications of the models.

Water-quality assessment of the Frank Lyon, Jr., nursery pond releases into Lake Maumelle, Arkansas, 1991-1996

USGS Publications Warehouse

Green, William Reed

1998-01-01

Releases of the Frank Lyon, Jr., Nursery Pond into Lake Maumelle were monitored during 1991 through 1996 to assess the impact that the releases have on the water quality of Lake Maumelle. Results indicated that the water-quality impact of the nursery pond release into Lake Maumelle is variable, and appears to be related to the volume of the nursery pond at release and the amount of fertilizer applied within the nursery pond earlier in the year. In 1991 through 1994 and in 1996, nursery pond release loads for nutrients (except for dissolved nitrite plus nitrate nitrogen), total and dissolved organic carbon, iron, and manganese were greater than what would be expected in the annual area load from that basin. In 1995, only ammonium nitrate was appliec to the nursery pond. As a result, the 1995 phosphorus load was lower than in other years, and was less than what would be expected in the annual areal load. Nutrient enrichment, on average, in Lake Maumelle from the nursery pond release resulted in what would be equivalent to an 8 percent increase in concentration of total phosphorus, 50 percent increase in dissolved orthophosphorus, 0.1 percent increase in dissolved nitrite plus nitrate nitrogen, 2.5 percent increase in total ammonia plus organic nitrogen, and 5.7 percent increase in dissolved ammonia nitrogen, assuming that the nutrient load was conservative and evenly distributed throughout the water body. Evidence of elevated turbidity, nutrient, and chlorphyll a concentrations in the epilimnetic water outside the receiving embayment were apparent for as long as 3 weeks after the 1995 and 1996 releases. In general, highest values were found at the site located where the receiving embayment meets the open water of Lake Maumelle. Much of the released material in the nursery pond originated in the cooler, anoxic hypolimnetic water. The initial release water was seen to plunge beneath the warmer water existing in the receiving embayment and was transported into the open water of Lake Maumelle, under the thermocline. The quantity of water and mass of constituents transported into the open water under the thermocline is unknown and probably remained isolated from the surface water until fall turnover.

Systems Performance Analyses of Alaska Wind-Diesel Projects; St. Paul, Alaska (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baring-Gould, I.

2009-04-01

This fact sheet summarizes a systems performance analysis of the wind-diesel project in St. Paul, Alaska. Data provided for this project include load data, average wind turbine output, average diesel plant output, dump (controlling) load, average net capacity factor, average net wind penetration, estimated fuel savings, and wind system availability.

Estimates of nitrogen loads entering Long Island Sound from ground water and streams on Long Island, New York, 1985–96

USGS Publications Warehouse

Scorca, Michael P.; Monti, Jack

2001-01-01

Fresh ground water that discharges from the northern part of Long Island's aquifer system to Long Island Sound contains elevated concentrations of nitrogen from agricultural fertilizer, domestic waste and fertilizer, and precipitation. The nitrogen contributes to algal blooms, which consume oxygen as the algae die and decompose. The resulting low dissolved oxygen concentrations (hypoxia) adversely affect plant and animal populations in Long Island Sound.The four major streams on the north shore of Long Island that have long-term discharge and water-quality records were selected for analysis of geographic, long-term, and seasonal trends in nitrogen concentration. Nitrogen concentrations generally decrease eastward among three Nassau County streams, then increase again at the easternmost stream, Nissequogue River in Suffolk County. A long-term (1970-96) increase in total nitrogen concentrations in the Nissequogue River also is evident. Seasonal fluctuations in nitrogen concentrations in all four streams reflect chemical reactions and microbial activity in the stream system, so total nitrogen concentrations in the three easternmost streams generally were lowest during summer and highest in winter, whereas those in the westernmost stream (Glen Cove Creek) were highest during summer and lowest in winter.The nitrogen loads discharged to Long Island Sound from each of the four streams for each year during 1985-96 were calculated from the annual mean total nitrogen concentration and the annual mean discharge. Nissequogue River's annual mean discharges were 3 to 6 times larger than those of Glen Cove and Mill Neck Creeks, and produced the largest annual loads of nitrogen--65 to 149 ton/yr (59,000 to 135,000 kg/yr). Cold Spring Brook had the lowest annual mean discharges and annual mean total nitrogen concentrations of the four streams; its annual mean nitrogen load ranged from 1.2 to 2.8 ton/yr (1,100 to 2,500 kg/yr).The nitrogen load carried to Long Island Sound by shallow ground water from the north shore of Long Island was calculated from simulated shallow-aquifer discharges from Nassau and Suffolk Counties (9,200 and 21,400 Mgal/yr or 34,800,000 and 81,100,000 m3/yr, respectively) and median total nitrogen concentrations at selected wells (2.2 and 4.3 milligrams per liter as N, respectively). The resultant nitrogen load was 84 ton/yr (76,500 kg/yr) for Nassau County and 384 ton/yr (349,000 kg/yr) for Suffolk County.The nitrogen load carried to Long Island Sound by deep ground water from the north shore was calculated from simulated deep-aquifer discharges from Nassau and Suffolk counties (13,200 and 47,300 Mgal/yr or 50,000,000 and 179,000,000 m3/yr, respectively). The median nitrogen concentrations of deep ground water for the two counties were 1.62 and 1.34 mg/L as N, respectively. The resultant nitrogen load from deep-aquifer discharge was 89 ton/yr (81,000 kg/yr) for Nassau County and 265 ton/yr (240,000 kg/yr) for Suffolk County.Nitrogen loads entering Long Island Sound from the shallow aquifer underlying three areas of differing land use along the north shore--a sewered residential area in Nassau County, an unsewered residential area in Suffolk County, and an agricultural area in Suffolk County--were evaluated. The agricultural area contains no major streams and, therefore, produces very little surface runoff to Long Island Sound and substantially greater shallow-aquifer discharge than in the sewered and unsewered areas. Ground water in the agricultural area also had the highest median nitrogen concentration (9.9 mg/L as N) of the three land-use areas and discharged the largest estimated nitrogen load to Long Island Sound--152 ton/yr (138,000 kg/yr), which represents about 40 percent of the estimated total nitrogen load from Suffolk County. Ground water in the sewered area had the lowest nitrogen concentration (1.9 mg/L as N) and discharged the smallest nitrogen load to Long Island Sound--7.28 ton/yr (6,600 kg/yr). The analysis indicates that land use on the north shore of Long Island can greatly affect the nitrogen concentration of water in the shallow aquifer and the resultant nitrogen load discharged to Long Island Sound from ground water.

AVERAGE ANNUAL SOLAR UV DOSE OF THE CONTINENTAL US CITIZEN

EPA Science Inventory

The average annual solar UV dose of US citizens is not known, but is required for relative risk assessments of skin cancer from UV-emitting devices. We solved this problem using a novel approach. The EPA's "National Human Activity Pattern Survey" recorded the daily ou...

14 CFR Appendix A to Part 187 - Methodology for Computation of Fees for Certification Services Performed Outside the United States

Code of Federal Regulations, 2013 CFR

2013-01-01

... hours of a U.S. Federal Government employee. This result in the hourly government paid cost of an... average annual leave hours and 1,800 average annual hours available for work for computer manpower...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 29 2010-07-01 2010-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2013-07-01 2013-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 29 2010-07-01 2010-07-01 false New source performance standards. 464...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2014-07-01 2014-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2013-07-01 2013-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2011-07-01 2011-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 29 2010-07-01 2010-07-01 false New source performance standards. 464...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2013-07-01 2013-07-01 false New source performance standards. 464...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2012-07-01 2012-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2014-07-01 2014-07-01 false New source performance standards. 464...

40 CFR 464.44 - New source performance standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2011-07-01 2011-07-01 false New source performance standards. 464...

40 CFR 464.24 - New source performance standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2012-07-01 2012-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2014-07-01 2014-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 30 2011-07-01 2011-07-01 false New source performance standards. 464...

40 CFR 464.14 - New source performance standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., total phenols, oil and grease, and TSS. For non-continuous dischargers, annual average mass standards.... Concentration standards and annual average mass standards shall only apply to non-continuous dischargers. (a... 40 Protection of Environment 31 2012-07-01 2012-07-01 false New source performance standards. 464...

Comparison of Selected EIA-782 Data With Other Data Sources

EIA Publications

2012-01-01

This article compares annual average prices reported from the EIA-782 survey series for residential No. 2 distillate, on-highway diesel fuel, retail regular motor gasoline, refiner No. 2 fuel oil for resale, refiner No. 2 diesel fuel for resale, refiner regular motor gasoline for resale, and refiner kerosene-type jet fuel for resale with annual average prices reported by other sources. In terms of volume, it compares EIA-782C Prime Supplier annual volumes for motor gasoline (all grades), distillate fuel oil, kerosene-type jet fuel and residual fuel oil with annual volumes from other sources.

Characterization of the electrical output of flat-plate photovoltaic arrays

NASA Technical Reports Server (NTRS)

Gonzalez, C. C.; Hill, G. M.; Ross, R. G., Jr.

1982-01-01

The electric output of flat-plate photovoltaic arrays changes constantly, due primarily to changes in cell temperature and irradiance level. As a result, array loads such as direct-current to alternating-current power conditioners must be able to accommodate widely varying input levels, while maintaining operation at or near the array maximum power point.The results of an extensive computer simulation study that was used to define the parameters necessary for the systematic design of array/power-conditioner interfaces are presented as normalized ratios of power-conditioner parameters to array parameters, to make the results universally applicable to a wide variety of system sizes, sites, and operating modes. The advantages of maximum power tracking and a technique for computing average annual power-conditioner efficiency are discussed.

Teratogens: a public health issue – a Brazilian overview

PubMed Central

Mazzu-Nascimento, Thiago; Melo, Débora Gusmão; Morbioli, Giorgio Gianini; Carrilho, Emanuel; Vianna, Fernanda Sales Luiz; da Silva, André Anjos; Schuler-Faccini, Lavinia

2017-01-01

Abstract Congenital anomalies are already the second cause of infant mortality in Brazil, as in many other middle-income countries in Latin America. Birth defects are a result of both genetic and environmental factors, but a multifactorial etiology has been more frequently observed. Here, we address the environmental causes of birth defects – or teratogens – as a public health issue and present their mechanisms of action, categories and their respective maternal-fetal deleterious effects. We also present a survey from 2008 to 2013 of Brazilian cases involving congenital anomalies (annual average of 20,205), fetal deaths (annual average of 1,530), infant hospitalizations (annual average of 82,452), number of deaths of hospitalized infants (annual average of 2,175), and the average cost of hospitalizations (annual cost of $7,758). Moreover, we report on Brazilian cases of teratogenesis due to the recent Zika virus infection, and to the use of misoprostol, thalidomide, alcohol and illicit drugs. Special attention has been given to the Zika virus infection, now proven to be responsible for the microcephaly outbreak in Brazil, with 8,039 cases under investigation (from October 2015 to June 2016). From those cases, 1,616 were confirmed and 324 deaths occurred due to microcephaly complications or alterations on the central nervous system. Congenital anomalies impact life quality and raise costs in specialized care, justifying the classification of teratogens as a public health issue. PMID:28534929