Surface-Water Nutrient Conditions and Sources in the United States Pacific Northwest1

PubMed Central

Wise, Daniel R; Johnson, Henry M

2011-01-01

Abstract The SPAtially Referenced Regressions On Watershed attributes (SPARROW) model was used to perform an assessment of surface-water nutrient conditions and to identify important nutrient sources in watersheds of the Pacific Northwest region of the United States (U.S.) for the year 2002. Our models included variables representing nutrient sources as well as landscape characteristics that affect nutrient delivery to streams. Annual nutrient yields were higher in watersheds on the wetter, west side of the Cascade Range compared to watersheds on the drier, east side. High nutrient enrichment (relative to the U.S. Environmental Protection Agency's recommended nutrient criteria) was estimated in watersheds throughout the region. Forest land was generally the largest source of total nitrogen stream load and geologic material was generally the largest source of total phosphorus stream load generated within the 12,039 modeled watersheds. These results reflected the prevalence of these two natural sources and the low input from other nutrient sources across the region. However, the combined input from agriculture, point sources, and developed land, rather than natural nutrient sources, was responsible for most of the nutrient load discharged from many of the largest watersheds. Our results provided an understanding of the regional patterns in surface-water nutrient conditions and should be useful to environmental managers in future water-quality planning efforts. PMID:22457584

Feasibility of Estimating Relative Nutrient Contributions of Agriculture and Forests Using MODIS Time Series

NASA Technical Reports Server (NTRS)

Ross, Kenton W.; Gasser, Gerald; Spiering, Bruce

2010-01-01

Around the Gulf of Mexico, high-input crops in several regions make a significant contribution to nutrient loading of small to medium estuaries and to the near-shore Gulf. Some crops cultivated near the coast include sorghum in Texas, rice in Texas and Louisiana, sugarcane in Florida and Louisiana, citrus orchards in Florida, pecan orchards in Mississippi and Alabama, and heavy sod and ornamental production around Mobile and Tampa Bay. In addition to crops, management of timberlands in proximity to the coasts also plays a role in nutrient loading. In the summer of 2008, a feasibility project is planned to explore the use of NASA data to enhance the spatial and temporal resolution of near-coast nutrient source information available to the coastal community. The purpose of this project is to demonstrate the viability of nutrient source information products applicable to small to medium watersheds surrounding the Gulf of Mexico. Conceptually, these products are intended to complement estuarine nutrient monitoring.

Feasibility of Estimating Relative Nutrient Contributions of Agriculture using MODIS Time Series

NASA Technical Reports Server (NTRS)

Ross, Kenton W.; Gasser, Gerald; Spiering, Bruce

2008-01-01

Around the Gulf of Mexico, high-input crops in several regions make a significant contribution to nutrient loading of small to medium estuaries and to the near-shore Gulf. Some crops cultivated near the coast include sorghum in Texas, rice in Texas and Louisiana, sugarcane in Florida and Louisiana, citrus orchards in Florida, pecan orchards in Mississippi and Alabama, and heavy sod and ornamental production around Mobile and Tampa Bay. In addition to crops, management of timberlands in proximity to the coasts also plays a role in nutrient loading. In the summer of 2008, a feasibility project is planned to explore the use of NASA data to enhance the spatial and temporal resolution of near-coast nutrient source information available to the coastal community. The purpose of this project is to demonstrate the viability of nutrient source information products applicable to small to medium watersheds surrounding the Gulf of Mexico. Conceptually, these products are intended to complement estuarine nutrient monitoring.

TERRESTRIAL AND MARINE SOURCES OF NUTRIENTS TO AN OREGON COASTAL RIVER

EPA Science Inventory

In the Pacific Northwest of North America, anadromous fish can transport significant quantities of nutrients and energy from the ocean to the watersheds where they return, reproduce and die. In addition, the widespread distribution of N2-fixing alders (Alnus spp.) can influence ...

Nutrient concentrations in coarse and fine woody debris of Populus tremuloides Michx.-dominated forests, northern Minnesota, USA

USGS Publications Warehouse

Klockow, Paul A.; D'Amato, Anthony W.; Bradford, John B.; Fraver, Shawn

2014-01-01

Contemporary forest harvesting practices, specifically harvesting woody biomass as a source of bioenergy feedstock, may remove more woody debris from a site than conventional harvesting. Woody debris, particularly smaller diameter woody debris, plays a key role in maintaining ecosystem nutrient stores following disturbance. Understanding nutrient concentrations within woody debris is necessary for assessing the long-term nutrient balance consequences of altered woody debris retention, particularly in forests slated for use as bioenergy feedstocks. Nutrient concentrations in downed woody debris of various sizes, decay classes, and species were characterized within one such forest type, Populus tremuloides Michx.-dominated forests of northern Minnesota, USA. Nutrient concentrations differed significantly between size and decay classes and generally increased as decay progressed. Fine woody debris (≤ 7.5 cm diameter) had higher nutrient concentrations than coarse woody debris (> 7.5 cm diameter) for all nutrients examined except Na and Mn, and nutrient concentrations varied among species. Concentrations of N, Mn, Al, Fe, and Zn in coarse woody debris increased between one and three orders of magnitude, while K decreased by an order of magnitude with progressing decay. The variations in nutrient concentrations observed here underscore the complexity of woody debris nutrient stores in forested ecosystems and suggest that retaining fine woody debris at harvest may provide a potentially important source of nutrients following intensive removals of bioenergy feedstocks.

Study on shrimp waste water and vermicompost as a nutrient source for bell peppers

USDA-ARS?s Scientific Manuscript database

The aquaculture industry generates significant nutrient-rich wastewater that is released into streams and rivers causing environmental concern. The objective of this controlled environment study was to evaluate the effect of waste shrimp water (SW), vermicompost (VC), at rates of 10%, 20%, 40%, and ...

Nutrient and phytoplankton analysis of a Mediterranean coastal area.

PubMed

Sebastiá, M T; Rodilla, M

2013-01-01

Identifying and quantifying the key anthropogenic nutrient input sources are essential to adopting management measures that can target input for maximum effect in controlling the phytoplankton biomass. In this study, three systems characterized by distinctive main nutrient sources were sampled along a Mediterranean coast transect. These sources were groundwater discharge in the Ahuir area, the Serpis river discharge in the Venecia area, and a submarine wastewater outfall 1,900 m from the coast. The study area includes factors considered important in determining a coastal area as a sensitive area: it has significant nutrient sources, tourism is a major source of income in the region, and it includes an area of high water residence time (Venecia area) which is affected by the harbor facilities and by wastewater discharges. We found that in the Ahuir and the submarine wastewater outfall areas, the effects of freshwater inputs were reduced because of a greater water exchange with the oligotrophic Mediterranean waters. On the other hand, in the Venecia area, the highest levels of nutrient concentration and phytoplankton biomass were attributed to the greatest water residence time. In this enclosed area, harmful dinoflagellates were detected (Alexandrium sp. and Dinophysis caudata). If the planned enlargement of the Gandia Harbor proceeds, it may increase the vulnerability of this system and provide the proper conditions of confinement for the dinoflagellate blooms' development. Management measures should first target phosphorus inputs as this is the most potential-limiting nutrient in the Venecia area and comes from a point source that is easier to control. Finally, we recommend that harbor environmental management plans include regular monitoring of water quality in adjacent waters to identify adverse phytoplankton community changes.

Sources and Transport of Nutrients, Organic Carbon, and Chlorophyll-a in the San Joaquin River Upstream of Vernalis, California, during Summer and Fall, 2000 and 2001

USGS Publications Warehouse

Kratzer, Charles R.; Dileanis, Peter D.; Zamora, Celia; Silva, Steven R.; Kendall, Carol; Bergamaschi, Brian A.; Dahlgren, Randy A.

2004-01-01

Oxidizable materials from the San Joaquin River upstream of Vernalis can contribute to low dissolved oxygen episodes in the Stockton Deep Water Ship Channel that can inhibit salmon migration in the fall. The U.S. Geological Survey collected and analyzed samples at four San Joaquin River sites in July through October 2000 and June through November 2001, and at eight tributary sites in 2001. The data from these sites were supplemented with data from samples collected and analyzed by the University of California at Davis at three San Joaquin River sites and eight tributary sites as part of a separate study. Streamflows in the San Joaquin River were slightly above the long-term average in 2000 and slightly below average in 2001. Nitrate loads at Vernalis in 2000 were above the long-term average, whereas loads in 2001 were close to average. Total nitrogen loads in 2000 were slightly above average, whereas loads in 2001 were slightly below average. Total phosphorus loads in 2000 and 2001 were well below average. These nutrient loads correspond with the flow-adjusted concentration trends--nitrate concentrations significantly increased since 1972 (p 0.05). Loading rates of nutrients and dissolved organic carbon increased in the San Joaquin River in the fall with the release of wetland drainage into Mud Slough and with increased reservoir releases on the Merced River. During August 2000 and September 2001, the chlorophyll-a loading rates and concentrations in the San Joaquin River declined and remained low during the rest of the sampling period. The most significant tributary sources of nutrients were the Tuolumne River, Harding Drain, and Mud Slough. The most significant tributary sources of dissolved organic carbon were Salt Slough, Mud Slough, and the Tuolumne and Stanislaus Rivers. Compared with nutrients and dissolved organic carbon, the tributaries were minor sources of chlorophyll-a, suggesting that most of the chlorophyll-a was produced in the San Joaquin River rather than its tributaries. On the basis of the carbon-to-nitrogen ratios and the d13C of particulate organic matter in the San Joaquin River and tributaries, the particulate organic matter in the river was mostly phytoplankton. On the basis of the d15N values of the particulate organic matter, and of total dissolved nitrogen and nitrate, the nitrate in the San Joaquin River probably was a significant nutrient source for the phytoplankton. The range of d15N and d18O values of nitrate in the San Joaquin River and tributaries suggest that animal waste or sewage was a significant source of nitrate in the river at the time the samples were collected.

Nutrient Mass Balance for the Mobile River Basin in Alabama, Georgia, and Mississippi

NASA Astrophysics Data System (ADS)

Harned, D. A.; Harvill, J. S.; McMahon, G.

2001-12-01

The source and fate of nutrients in the Mobile River drainage basin are important water-quality concerns in Alabama, Georgia, and Mississippi. Land cover in the basin is 74 percent forested, 16 percent agricultural, 2.5 percent developed, and 4 percent wetland. A nutrient mass balance calculated for 18 watersheds in the Mobile River Basin indicates that agricultural non-point nitrogen and phosphorus sources and urban non-point nitrogen sources are the most important factors associated with nutrients in the streams. Nitrogen and phosphorus inputs from atmospheric deposition, crop fertilizer, biological nitrogen fixation, animal waste, and point sources were estimated for each of the 18 drainage basins. Total basin nitrogen inputs ranged from 27 to 93 percent from atmospheric deposition (56 percent mean), 4 to 45 percent from crop fertilizer (25 percent mean), <0.01 to 31 percent from biological nitrogen fixation (8 percent mean), 2 to 14 percent from animal waste (8 percent mean), and 0.2 to 11 percent from point sources (3 percent mean). Total basin phosphorus inputs ranged from 10 to 39 percent from atmospheric deposition (26 percent mean), 7 to 51 percent from crop fertilizer (28 percent mean), 20 to 64 percent from animal waste (41 percent mean), and 0.2 to 11 percent from point sources (3 percent mean). Nutrient outputs for the watersheds were estimated by calculating instream loads and estimating nutrient uptake, or withdrawal, by crops. The difference between the total basin inputs and outputs represents nutrients that are retained or processed within the basin while moving from the point of use to the stream, or in the stream. Nitrogen output, as a percentage of the total basin nitrogen inputs, ranged from 19 to 79 percent for instream loads (35 percent mean) and from 0.01 to 32 percent for crop harvest (10 percent mean). From 53 to 87 percent (75 percent mean) of nitrogen inputs were retained within the 18 basins. Phosphorus output ranged from 9 to 29 percent for instream loads (18 percent mean) and from 0.01 to 23 percent for crop harvest (7 percent mean). The basins retained from 60 to 87 percent (74 percent mean) of phosphorous inputs. Correlation of basin nutrient output loads and concentrations with the basin inputs and correlation of output loads and concentrations with basin land use were tested using the Spearman rank test. The correlation analysis indicated that higher nitrogen concentrations in the streams are associated with urban areas and higher loads are associated with agriculture; high phosphorus output loads and concentrations are associated with agriculture. Higher nutrient loads in agricultural basins are partly an effect of basin size-- larger basins generate larger nutrient loads. Nutrient loads and concentrations showed no significant correlation to point-source inputs. Nitrogen loads were significantly (p<0.05, correlation coefficient >0.5) higher in basins with greater cropland areas. Nitrogen concentrations also increased as residential, commercial, and total urban areas increased. Phosphorus loads were positively correlated with animal-waste inputs, pasture, and total agricultural land. Phosphorus concentrations were highest in basins with the greatest amounts of row-crop agriculture.

Investigation of utilization of the algal biomass residue after oil extraction to lower the total production cost of biodiesel.

PubMed

Gao, Min-Tian; Shimamura, Takashi; Ishida, Nobuhiro; Takahashi, Haruo

2012-09-01

In this study, component analysis of a novel biodiesel-producing alga, Pseudochoricystis ellipsoidea, was performed. The component analysis results indicated that proteins and amino acids are abundant in P. ellipsoidea while the sugar content is relatively low. Rather than its use as a carbon source, the use of the algal biomass residue after oil extraction as a nutrient source provided a new way for lowering the total production cost of biodiesel. In both lactic acid and ethanol fermentations, the use of the residue instead of high-cost nutrient yeast extract allowed a significant saving, showing the promise of the algal biomass residue for use as a fermentation nutrient source. Copyright © 2012 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Trends in energy intake among Korean adults, 1998-2015: Results from the Korea National Health and Nutrition Examination Survey.

PubMed

Yun, Sungha; Kim, Hyun Ja; Oh, Kyungwon

2017-04-01

Assessing changes in energy intake and dietary sources is important to understand trends in the prevalence of obesity. Thus, we examined trends in energy intake and its nutrient and food sources in Korean adults from 1998 through 2015. This study included 70,769 subjects aged ≥ 19 years who completed a nutrition survey. Subject data were obtained from the 1998, 2001, 2005, 2007-2009, 2010-2012, and 2013-2015 Korea National Health and Nutrition Examination Surveys. Dietary intake was assessed by a 1-day 24-hour recall method. In men, the daily energy intake significantly increased from 2,196 kcal in 1998 to 2,489 kcal in 2013-2015 ( P for trend < 0.0001). However, the daily energy intake among women did not change significantly over the same period ( P for trend = 0.5772). The percentages of energy intake from animal foods (e.g., meat and milk) and beverages increased during the study period in both men and women. However, the percentage of energy intake from plant foods decreased due to a marked decrease in the intake of white rice. Changes in food sources of energy intake led to changes in the nutrient sources of energy intake; for example, the increase of energy intake from fat and decrease of energy intake from carbohydrate. This study suggests that since 1998, energy intake has increased among Korean adult men, but not among women. However, the composition of food and nutrient sources of energy intake has changed in both men and women. Energy intake and its nutrient and food sources should continue to be monitored regularly in the Korean adult population.

Nutrient Dynamics of Estuarine Invertebrates Are Shaped by Feeding Guild Rather than Seasonal River Flow

PubMed Central

Ortega-Cisneros, Kelly; Scharler, Ursula M.

2015-01-01

This study aimed to determine the variability of carbon and nitrogen elemental content, stoichiometry and diet proportions of invertebrates in two sub-tropical estuaries in South Africa experiencing seasonal changes in rainfall and river inflow. The elemental ratios and stable isotopes of abiotic sources, zooplankton and macrozoobenthos taxa were analyzed over a dry/wet seasonal cycle. Nutrient content (C, N) and stoichiometry of suspended particulate matter exhibited significant spatio-temporal variations in both estuaries, which were explained by the variability in river inflow. Sediment particulate matter (%C, %N and C:N) was also influenced by the variability in river flow but to a lesser extent. The nutrient content and ratios of the analyzed invertebrates did not significantly vary among seasons with the exception of the copepod Pseudodiaptomus spp. (C:N) and the tanaid Apseudes digitalis (%N, C:N). These changes did not track the seasonal variations of the suspended or sediment particulate matter. Our results suggest that invertebrates managed to maintain their stoichiometry independent of the seasonality in river flow. A significant variability in nitrogen content among estuarine invertebrates was recorded, with highest % N recorded from predators and lowest %N from detritivores. Due to the otherwise general lack of seasonal differences in elemental content and stoichiometry, feeding guild was a major factor shaping the nutrient dynamics of the estuarine invertebrates. The nutrient richer suspended particulate matter was the preferred food source over sediment particulate matter for most invertebrate consumers in many, but not all seasons. The most distinct preference for suspended POM as a food source was apparent from the temporarily open/closed system after the estuary had breached, highlighting the importance of river flow as a driver of invertebrate nutrient dynamics under extreme events conditions. Moreover, our data showed that estuarine invertebrates concentrated C and N between 10–100 fold from trophic level I (POM) to trophic level II (detritivores/deposit feeders) and thus highlighted their importance not only as links to higher trophic level organisms in the food web, but also as providers of a stoichiometrically homeostatic food source for such consumers. As climate change scenarios for the east coast of South Africa predict increased rainfall as a higher number of rainy days and days with higher rainfall, our results suggest that future changes in rainfall and river inflow will have measurable effects on the nutrient content and stoichiometry of food sources and possibly also in estuarine consumers. PMID:26352433

Nutrient Dynamics of Estuarine Invertebrates Are Shaped by Feeding Guild Rather than Seasonal River Flow.

PubMed

Ortega-Cisneros, Kelly; Scharler, Ursula M

2015-01-01

This study aimed to determine the variability of carbon and nitrogen elemental content, stoichiometry and diet proportions of invertebrates in two sub-tropical estuaries in South Africa experiencing seasonal changes in rainfall and river inflow. The elemental ratios and stable isotopes of abiotic sources, zooplankton and macrozoobenthos taxa were analyzed over a dry/wet seasonal cycle. Nutrient content (C, N) and stoichiometry of suspended particulate matter exhibited significant spatio-temporal variations in both estuaries, which were explained by the variability in river inflow. Sediment particulate matter (%C, %N and C:N) was also influenced by the variability in river flow but to a lesser extent. The nutrient content and ratios of the analyzed invertebrates did not significantly vary among seasons with the exception of the copepod Pseudodiaptomus spp. (C:N) and the tanaid Apseudes digitalis (%N, C:N). These changes did not track the seasonal variations of the suspended or sediment particulate matter. Our results suggest that invertebrates managed to maintain their stoichiometry independent of the seasonality in river flow. A significant variability in nitrogen content among estuarine invertebrates was recorded, with highest % N recorded from predators and lowest %N from detritivores. Due to the otherwise general lack of seasonal differences in elemental content and stoichiometry, feeding guild was a major factor shaping the nutrient dynamics of the estuarine invertebrates. The nutrient richer suspended particulate matter was the preferred food source over sediment particulate matter for most invertebrate consumers in many, but not all seasons. The most distinct preference for suspended POM as a food source was apparent from the temporarily open/closed system after the estuary had breached, highlighting the importance of river flow as a driver of invertebrate nutrient dynamics under extreme events conditions. Moreover, our data showed that estuarine invertebrates concentrated C and N between 10-100 fold from trophic level I (POM) to trophic level II (detritivores/deposit feeders) and thus highlighted their importance not only as links to higher trophic level organisms in the food web, but also as providers of a stoichiometrically homeostatic food source for such consumers. As climate change scenarios for the east coast of South Africa predict increased rainfall as a higher number of rainy days and days with higher rainfall, our results suggest that future changes in rainfall and river inflow will have measurable effects on the nutrient content and stoichiometry of food sources and possibly also in estuarine consumers.

Impact of Submarine Groundwater Discharge on Marine Water Quality and Reef Biota of Maui

PubMed Central

Bishop, James M.

2016-01-01

Generally unseen and infrequently measured, submarine groundwater discharge (SGD) can transport potentially large loads of nutrients and other land-based contaminants to coastal ecosystems. To examine this linkage we employed algal bioassays, benthic community analysis, and geochemical methods to examine water quality and community parameters of nearshore reefs adjacent to a variety of potential, land-based nutrient sources on Maui. Three common reef algae, Acanthophora spicifera, Hypnea musciformis, and Ulva spp. were collected and/or deployed at six locations with SGD. Algal tissue nitrogen (N) parameters (δ15N, N %, and C:N) were compared with nutrient and δ15N-nitrate values of coastal groundwater and nearshore surface water at all locations. Benthic community composition was estimated for ten 10-m transects per location. Reefs adjacent to sugarcane farms had the greatest abundance of macroalgae, low species diversity, and the highest concentrations of N in algal tissues, coastal groundwater, and marine surface waters compared to locations with low anthropogenic impact. Based on δ15N values of algal tissues, we estimate ca. 0.31 km2 of Kahului Bay is impacted by effluent injected underground at the Kahului Wastewater Reclamation Facility (WRF); this region is barren of corals and almost entirely dominated by colonial zoanthids. Significant correlations among parameters of algal tissue N with adjacent surface and coastal groundwater N indicate that these bioassays provided a useful measure of nutrient source and loading. A conceptual model that uses Ulva spp. tissue δ15N and N % to identify potential N source(s) and relative N loading is proposed for Hawaiʻi. These results indicate that SGD can be a significant transport pathway for land-based nutrients with important biogeochemical and ecological implications in tropical, oceanic islands. PMID:27812171

Impact of Submarine Groundwater Discharge on Marine Water Quality and Reef Biota of Maui.

PubMed

Amato, Daniel W; Bishop, James M; Glenn, Craig R; Dulai, Henrietta; Smith, Celia M

2016-01-01

Generally unseen and infrequently measured, submarine groundwater discharge (SGD) can transport potentially large loads of nutrients and other land-based contaminants to coastal ecosystems. To examine this linkage we employed algal bioassays, benthic community analysis, and geochemical methods to examine water quality and community parameters of nearshore reefs adjacent to a variety of potential, land-based nutrient sources on Maui. Three common reef algae, Acanthophora spicifera, Hypnea musciformis, and Ulva spp. were collected and/or deployed at six locations with SGD. Algal tissue nitrogen (N) parameters (δ15N, N %, and C:N) were compared with nutrient and δ15N-nitrate values of coastal groundwater and nearshore surface water at all locations. Benthic community composition was estimated for ten 10-m transects per location. Reefs adjacent to sugarcane farms had the greatest abundance of macroalgae, low species diversity, and the highest concentrations of N in algal tissues, coastal groundwater, and marine surface waters compared to locations with low anthropogenic impact. Based on δ15N values of algal tissues, we estimate ca. 0.31 km2 of Kahului Bay is impacted by effluent injected underground at the Kahului Wastewater Reclamation Facility (WRF); this region is barren of corals and almost entirely dominated by colonial zoanthids. Significant correlations among parameters of algal tissue N with adjacent surface and coastal groundwater N indicate that these bioassays provided a useful measure of nutrient source and loading. A conceptual model that uses Ulva spp. tissue δ15N and N % to identify potential N source(s) and relative N loading is proposed for Hawai'i. These results indicate that SGD can be a significant transport pathway for land-based nutrients with important biogeochemical and ecological implications in tropical, oceanic islands.

Effect of nutrient enrichment on the source and composition of sediment organic carbon in tropical seagrass beds in the South China Sea.

PubMed

Liu, Songlin; Jiang, Zhijian; Zhang, Jingping; Wu, Yunchao; Lian, Zhonglian; Huang, Xiaoping

2016-09-15

To assess the effect of nutrient enrichment on the source and composition of sediment organic carbon (SOC) beneath Thalassia hemprichii and Enhalus acoroides in tropical seagrass beds, Xincun Bay, South China Sea, intertidal sediment, primary producers, and seawater samples were collected. No significant differences on sediment δ(13)C, SOC, and microbial biomass carbon (MBC) were observed between T. hemprichii and E. acoroides. SOC was mainly of autochthonous origin, while the contribution of seagrass to SOC was less than that of suspended particulate organic matter, macroalgae and epiphytes. High nutrient concentrations contributed substantially to SOC of seagrass, macroalgae, and epiphytes. The SOC, MBC, and MBC/SOC ratio in the nearest transect to fish farming were the highest. This suggested a more labile composition of SOC and shorter turnover times in higher nutrient regions. Therefore, the research indicates that nutrient enrichment could enhance plant-derived contributions to SOC and microbial use efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of biomass burning on nutrient deposition to the global ocean

NASA Astrophysics Data System (ADS)

Kanakidou, Maria; Myriokefalitakis, Stelios; Daskalakis, Nikos; Mihalopoulos, Nikolaos; Nenes, Athanasios

2017-04-01

Atmospheric deposition of trace constituents, both of natural and anthropogenic origin, can act as a nutrient source into the open ocean and affect marine ecosystem functioning and subsequently the exchange of CO2 between the atmosphere and the global ocean. Dust is known as a major source of nutrients (Fe and P) into the atmosphere, but only a fraction of these nutrients is released in soluble form that can be assimilated by the ecosystems. Dust is also known to enhance N deposition by interacting with anthropogenic pollutants and neutralisation of part of the acidity of the atmosphere by crustal alkaline species. These nutrients have also primary anthropogenic sources including combustion emissions. The global atmospheric N [1], Fe [2] and P [3] cycles have been parameterized in the global 3-D chemical transport model TM4-ECPL, accounting for inorganic and organic forms of these nutrients, for all natural and anthropogenic sources of these nutrients including biomass burning, as well as for the link between the soluble forms of Fe and P atmospheric deposition and atmospheric acidity. The impact of atmospheric acidity on nutrient solubility has been parameterised based on experimental findings and the model results have been evaluated by extensive comparison with available observations. In the present study we isolate the significant impact of biomass burning emissions on these nutrients deposition by comparing global simulations that consider or neglect biomass burning emissions. The investigated impact integrates changes in the emissions of the nutrients as well as in atmospheric oxidants and acidity and thus in atmospheric processing and secondary sources of these nutrients. The results are presented and thoroughly discussed. References [1] Kanakidou M, S. Myriokefalitakis, N. Daskalakis, G. Fanourgakis, A. Nenes, A. Baker, K. Tsigaridis, N. Mihalopoulos, Past, Present and Future Atmospheric Nitrogen Deposition, Journal of the Atmospheric Sciences (JAS-D-15-0278) Vol 73, 2039-2047, 2016. [2] Myriokefalitakis,S., Daskalakis,N., Mihalopoulos,N., Baker, A.R., Nenes, A., and Kanakidou,M.: Changes in dissolved iron deposition to the oceans driven by human activity: a 3-D global modelling study, Biogeosciences, 12, 3973-3992, 2015. [3] Myriokefalitakis S., Nenes A., Baker A.R., Mihalopoulos N., Kanakidou M.: Bioavailable atmospheric phosphorous supply to the global ocean: a 3-D global modelling study, Biogeosciences, 13, 6519-6543, 2016.

Effects of salt pond restoration on benthic flux: Sediment as a source of nutrients to the water column

USGS Publications Warehouse

Topping, Brent R.; Kuwabara, James S.; Carter, James L.; Garrettt, Krista K.; Mruz, Eric; Piotter, Sarah; Takekawa, John Y.

2016-01-01

Understanding nutrient flux between the benthos and the overlying water (benthic flux) is critical to restoration of water quality and biological resources because it can represent a major source of nutrients to the water column. Extensive water management commenced in the San Francisco Bay, Beginning around 1850, San Francisco Bay wetlands were converted to salt ponds and mined extensively for more than a century. Long-term (decadal) salt pond restoration efforts began in 2003. A patented device for sampling porewater at varying depths, to calculate the gradient, was employed between 2010 and 2012. Within the former ponds, the benthic flux of soluble reactive phosphorus and that of dissolved ammonia were consistently positive (i.e., moving out of the sediment into the water column). The lack of measurable nitrate or nitrite concentration gradients across the sediment-water interface suggested negligible fluxes for dissolved nitrate and nitrite. The dominance of ammonia in the porewater indicated anoxic sediment conditions, even at only 1 cm depth, which is consistent with the observed, elevated sediment oxygen demand. Nearby openestuary sediments showed much lower benthic flux values for nutrients than the salt ponds under resortation. Allochthonous solute transport provides a nutrient advective flux for comparison to benthic flux. For ammonia, averaged for all sites and dates, benthic flux was about 80,000 kg/year, well above the advective flux range of −50 to 1500 kg/year, with much of the variability depending on the tidal cycle. By contrast, the average benthic flux of soluble reactive phosphorus was about 12,000 kg/year, of significant magnitude, but less than the advective flux range of 21,500 to 30,000 kg/year. These benthic flux estimates, based on solute diffusion across the sediment-water interface, reveal a significant nutrient source to the water column of the pond which stimulates algal blooms (often autotrophic). This benthic source may be augmented further by bioturbation, bioirrigation and episodic sediment resuspension events.

Analyzing Variability in Landscape Nutrient Loading Using Spatially-Explicit Maps in the Great Lakes Basin

NASA Astrophysics Data System (ADS)

Hamlin, Q. F.; Kendall, A. D.; Martin, S. L.; Whitenack, H. D.; Roush, J. A.; Hannah, B. A.; Hyndman, D. W.

2017-12-01

Excessive loading of nitrogen and phosphorous to the landscape has caused biologically and economically damaging eutrophication and harmful algal blooms in the Great Lakes Basin (GLB) and across the world. We mapped source-specific loads of nitrogen and phosphorous to the landscape using broadly available data across the GLB. SENSMap (Spatially Explicit Nutrient Source Map) is a 30m resolution snapshot of nutrient loads ca. 2010. We use these maps to study variable nutrient loading and provide this information to watershed managers through NOAA's GLB Tipping Points Planner. SENSMap individually maps nutrient point sources and six non-point sources: 1) atmospheric deposition, 2) septic tanks, 3) non-agricultural chemical fertilizer, 4) agricultural chemical fertilizer, 5) manure, and 6) nitrogen fixation from legumes. To model source-specific loads at high resolution, SENSMap synthesizes a wide range of remotely sensed, surveyed, and tabular data. Using these spatially explicit nutrient loading maps, we can better calibrate local land use-based water quality models and provide insight to watershed managers on how to focus nutrient reduction strategies. Here we examine differences in dominant nutrient sources across the GLB, and how those sources vary by land use. SENSMap's high resolution, source-specific approach offers a different lens to understand nutrient loading than traditional semi-distributed or land use based models.

Nutrient transitions are a source of persisters in Escherichia coli biofilms.

PubMed

Amato, Stephanie M; Brynildsen, Mark P

2014-01-01

Chronic and recurrent infections have been attributed to persisters in biofilms, and despite this importance, the mechanisms of persister formation in biofilms remain unclear. The plethora of biofilm characteristics that could give rise to persisters, including slower growth, quorum signaling, oxidative stress, and nutrient heterogeneity, have complicated efforts to delineate formation pathways that generate persisters during biofilm development. Here we sought to specifically determine whether nutrient transitions, which are a common metabolic stress encountered within surface-attached communities, stimulate persister formation in biofilms and if so, to then identify the pathway. To accomplish this, we established an experimental methodology where nutrient availability to biofilm cells could be controlled exogenously, and then used that method to discover that diauxic carbon source transitions stimulated persister formation in Escherichia coli biofilms. Previously, we found that carbon source transitions stimulate persister formation in planktonic E. coli cultures, through a pathway that involved ppGpp and nucleoid-associated proteins, and therefore, tested the functionality of that pathway in biofilms. Biofilm persister formation was also found to be dependent on ppGpp and nucleoid-associated proteins, but the importance of specific proteins and enzymes between biofilm and planktonic lifestyles was significantly different. Data presented here support the increasingly appreciated role of ppGpp as a central mediator of bacterial persistence and demonstrate that nutrient transitions can be a source of persisters in biofilms.

An investigation of submarine groundwater-borne nutrient fluxes to the west Florida shelf and recurrent harmful algal blooms

USGS Publications Warehouse

Smith, Christopher G.; Swarzenski, Peter W.

2012-01-01

A cross-shelf, water-column mass balance of radon-222 (222Rn) provided estimates of submarine groundwater discharge (SGD), which were then used to quantify benthic nutrient fluxes. Surface water and groundwater were collected along a shore-normal transect that extended from Tampa Bay, Florida, across the Pinellas County peninsula, to the 10-m isobath in the Gulf of Mexico. Samples were analyzed for 222Rn and radium-223,224,226 (223,224,226Ra) activities as well as inorganic and organic nutrients. Cross-shore gradients of 222Rn and 223,224,226Ra activities indicate a nearshore source for these isotopes, which mixes with water characterized by low activities offshore. Radon-based SGD rates vary between 2.5 and 15 cm d-1 proximal to the shoreline and decrease offshore. The source of SGD is largely shallow exchange between surface and pore waters, although deeper groundwater cycling may also be important. Enrichment of total dissolved nitrogen and soluble reactive phosphorus in pore water combined with SGD rates results in specific nutrient fluxes comparable to or greater than estuarine fluxes from Tampa Bay. The significance of these fluxes to nearshore blooms of Karenia brevis is highlighted by comparison with prescribed nutrient demands for bloom maintenance and growth. Whereas our flux estimates do not indicate SGD and benthic fluxes as the dominant nutrient source to the harmful algal blooms, SGD-derived loads do narrow the deficit between documented nutrient supplies and bloom demands.

Food crop production, nutrient availability, and nutrient intakes in Bangladesh: exploring the agriculture-nutrition nexus with the 2010 Household Income and Expenditure Survey.

PubMed

Fiedler, John L

2014-12-01

Systematic collection of national agricultural data has been neglected in many low- and middle-income countries for the past 20 years. Commonly conducted nationally representative household surveys collect substantial quantities of highly underutilized food crop production data. To demonstrate the potential usefulness of commonly available household survey databases for analyzing the agriculture-nutrition nexus. Using household data from the 2010 Bangladesh Household Income and Expenditure Survey, the role and significance of crop selection, area planted, yield, nutrient production, and the disposition of 34 food crops in affecting the adequacy of farming households' nutrient availability and nutrient intake status are explored. The adequacy of each farming household's available energy, vitamin A, calcium, iron, and zinc and households' apparent intakes and intake adequacies are estimated. Each household's total apparent nutrient intake adequacies are estimated, taking into account the amount of each crop that households consume from their own production, together with food purchased or obtained from other sources. Even though rice contains relatively small amounts of micronutrients, has relatively low nutrient density, and is a relatively poor source of nutrients compared with what other crops can produce on a given tract of land, because so much rice is produced in Bangladesh, it is the source of 90% of the total available energy, 85% of the zinc, 67% of the calcium, and 55% of the iron produced by the agricultural sector. The domination of agriculture and diet by rice is a major constraint to improving nutrition in Bangladesh. Simple examples of how minor changes in the five most common cropping patterns could improve farming households' nutritional status are provided. Household surveys' agricultural modules can provide a useful tool for better understanding national nutrient production realities and possibilities.

Couplings of watersheds and coastal waters: Sources and consequences of nutrient enrichment in Waquoit Bay, Massachusetts

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

Valiela, I.; Foreman, K.; LaMontagne, M.

1992-12-01

Human activities on coastal watersheds provide the major sources of nutrients entering shallow coastal ecosystems. Nutrient loadings from watersheds alter structure and function of receiving aquatic ecosystems. To investigate this coupling of land to marine systems, a series of subwatersheds of Waquoit Bay differing in degree of urbanization and with widely different nutrient loading rates was studied. The subwatersheds differ in septic tanks numbers and forest acreage. Ground water is the major mechanism that transports nutrients to coastal waters. Some attenuation of nutrient concentrations within the aquifer or at the sediment-water interface, but significant increases in the nutrient content ofmore » groundwater arriving at the shore's edge are in urbanized areas. The groundwater flows through the sediment-water boundary, and sufficient groundwater-borne nutrients (nitrogen in particular) traverse the sediment-water boundary to cause significant changes in the aquatic ecosystem. These loading-dependent alterations include increased nutrients in water, greater primary production by phytoplankton, and increased macroalgal biomass and growth. The increased macroalgal biomass dominates the bay ecosystem through second- or third-order effects such as alterations of nutrient status of water columns and increasing frequency of anoxic events. The increases in seaweeds have decreased the areas covered by eelgrass habitats. The change in habitat type, plus the increased frequency of anoxic events, change the composition of the benthic fauna. The importance of bottom-up control in shallow coastal food webs is evident. The coupling of land to sea by groundwater-borne nutrient transport is mediated by a complex series of steps, making it unlikely to find a one-to-one relation between land use and conditions in the aquatic ecosystem. Appropriate models may provide a way to deal with the complexities of the coupling. 22 refs., 14 figs., 5 tabs.« less

Blending water- and nutrient-source wastewaters for cost-effective cultivation of high lipid content microalgal species Micractinium inermum NLP-F014.

PubMed

Park, Seonghwan; Kim, Jeongmi; Yoon, Youngjin; Park, Younghyun; Lee, Taeho

2015-12-01

The possibility of utilizing blended wastewaters from different streams was investigated for cost-efficient microalgal cultivation. The influent of a domestic wastewater treatment plant and the liquid fertilizer from a swine wastewater treatment plant were selected as water- and nutrient-source wastewaters, respectively. The growth of Micractinium inermum NLP-F014 in the blended wastewater medium without any pretreatment was comparable to that in Bold's Basal Medium. The optimum blending ratio of 5-15% (vv(-1)) facilitated biomass production up to 5.7 g-dry cell weight (DCW) L(-1), and the maximum biomass productivity (1.03 g-DCWL(-1)d(-1)) was achieved after three days of cultivation. Nutrient depletion induced lipid accumulation in the cell up to 39.1% (ww(-1)) and the maximum lipid productivity was 0.19 g-FAMEL(-1)d(-1). These results suggest that blending water- and nutrient-source wastewaters at a proper ratio without pretreatment can significantly cut costs in microalgae cultivation for biodiesel production. Copyright © 2015 Elsevier Ltd. All rights reserved.

A smart market for nutrient credit trading to incentivize wetland construction

NASA Astrophysics Data System (ADS)

Raffensperger, John F.; Prabodanie, R. A. Ranga; Kostel, Jill A.

2017-03-01

Nutrient trading and constructed wetlands are widely discussed solutions to reduce nutrient pollution. Nutrient markets usually include agricultural nonpoint sources and municipal and industrial point sources, but these markets rarely include investors who construct wetlands to sell nutrient reduction credits. We propose a new market design for trading nutrient credits, with both point source and non-point source traders, explicitly incorporating the option of landowners to build nutrient removal wetlands. The proposed trading program is designed as a smart market with centralized clearing, done with an optimization. The market design addresses the varying impacts of runoff over space and time, and the lumpiness of wetland investments. We simulated the market for the Big Bureau Creek watershed in north-central Illinois. We found that the proposed smart market would incentivize wetland construction by assuring reasonable payments for the ecosystem services provided. The proposed market mechanism selects wetland locations strategically taking into account both the cost and nutrient removal efficiencies. The centralized market produces locational prices that would incentivize farmers to reduce nutrients, which is voluntary. As we illustrate, wetland builders' participation in nutrient trading would enable the point sources and environmental organizations to buy low cost nutrient credits.

NUTRIENT FLUX AT THE SEDIMENT-WATER INTERFACE IN ESCAMBIA BAY, FL, A NORTHERN GULF OF MEXICO ESTUARY INVITED SEMINAR

EPA Science Inventory

(Abstract). Presented at the University of Texas Marine Science Institute, 30 April 2001, Port Aransas, TX. 1 p. (ERL,GB R841).

Nutrient flux at the sediment-water interface is an integral component of estuarine dynamics, and the benthos may represent a significant source ...

The distribution of nutrients, dissolved oxygen and chlorophyll a in the upper Gulf of Nicoya, Costa Rica, a tropical estuary.

PubMed

Palter, Jaime; Coto, Sandra León; Ballestero, Daniel

2007-06-01

In the Gulf of Nicoya on the Pacific Coast of Costa Rica, nutrient rich equatorial subsurface water (ESW) is upwelled in much of the lower gulf. These offshore waters are often regarded as the major source of nutrients to the gulf. However, for most of the year, the ESW has little influence on the nutrient content of the upper gulf, which has a distinct character from the lower gulf. The upper gulf, extending 40 km north of the restriction between Puntarenas Peninsula and San Lucas Island, is bordered primarily by mangrove swamps, is less than 20 m deep, and is less saline than the lower gulf. We surveyed the upper gulf for dissolved inorganic nitrogen, phosphate, silicate, dissolved oxygen, and chlorophyll in November 2000, January and July 2001. All nutrients are more concentrated in the upper gulf during the rainy and transitional seasons than the dry season, significantly so for phosphate and silicate. Throughout the year, nutrients tend to be much more concentrated in the less saline water of the upper gulf. This trend indicates that discharge from the Tempisque River predominantly controls spatial and temporal nutrient variability in the upper gulf. However, nutrient rich ESW, upwelled offshore and mixed to form a mid-temperature intermediate water, may enter the inner gulf to provide an important secondary source of nutrients during the dry season.

Effects of Land Use Land Cover (LULC) and Climate on Simulation of Phosphorus loading in the Southeast United States Region

NASA Astrophysics Data System (ADS)

Jima, T. G.; Roberts, A.

2013-12-01

Quality of coastal and freshwater resources in the Southeastern United States is threatened due to Eutrophication as a result of excessive nutrients, and phosphorus is acknowledged as one of the major limiting nutrients. In areas with much non-point source (NPS) pollution, land use land cover and climate have been found to have significant impact on water quality. Landscape metrics applied in catchment and riparian stream based nutrient export models are known to significantly improve nutrient prediction. The regional SPARROW (Spatially Referenced Regression On Watershed attributes), which predicts Total Phosphorus has been developed by the Southeastern United States regions USGS, as part of the National Water Quality Assessment (NAWQA) program and the model accuracy was found to be 67%. However, landscape composition and configuration metrics which play a significant role in the source, transport and delivery of the nutrient have not been incorporated in the model. Including these matrices in the models parameterization will improve the models accuracy and improve decision making process for mitigating and managing NPS phosphorus in the region. The National Land Cover Data 2001 raster data will be used (since the base line is 2002) for the region (with 8321 watersheds ) with fragstats 4.1 and ArcGIS Desktop 10.1 for the analysis of landscape matrices, buffers and creating map layers. The result will be imported to the Southeast SPARROW model and will be analyzed. Resulting statistical significance and model accuracy will be assessed and predictions for those areas with no water quality monitoring station will be made.

Watershed delineation and nitrogen source analysis for Bayou Chico, an urban watershed in northwest Florida

EPA Science Inventory

Nutrient pollution in stormwater runoff from urbanized areas contributes to water quality degradation in streams and receiving waterbodies. Agriculture, population growth, and industrial activities are significant sources of nitrogen inputs for surface waters. Increased nitrogen ...

Eutrophication of Buttermilk Bay, a cape cod coastal embayment: Concentrations of nutrients and watershed nutrient budgets

NASA Astrophysics Data System (ADS)

Valiela, Ivan; Costa, Joseph E.

1988-07-01

Nutrient concentrations in Buttermilk Bay, a coastal embayment on the northern end of Buzzards Bay, MA, are higher in the nearshore where salinities are lower. This pattern suggests that freshwater sources may contribute significantly to nutrient inputs into Buttermilk Bay. To evaluate the relative importance of the various sources we estimated inputs of nutrients by each major source into the watershed and into the bay itself. Septic systems contributed about 40% of the nitrogen and phosphorus entering the watershed, with precipitation and fertilizer use adding the remainder. Groundwater transported over 85% of the nitrogen and 75% of the phosphorus entering the bay. Most nutrients entering the watershed failed to reach the bay; uptake by forests, soils, denitrification, and adsorption intercepted two-thirds of the nitrogen and nine-tenths of the phosphorus that entered the watershed. The nutrients that did reach the bay most likely originated from subsoil injections into groundwater by septic tanks, plus some leaching of fertilizers. Buttermilk Bay water has relatively low nutrient concentrations, probably because of uptake of nutrients by macrophytes and because of relatively rapid tidal flushing. Annual budgets of nutrients entering the watershed showed a low nitrogen-to-phosphorus ratio of 6, but passage of nutrients through the watershed raised N/P to 23, probably because of adsorption of PO4 during transit. The N/P ratio of water that leaves the watershed and presumably enters the bay is probably high enough to maintain active growth of nitrogenlimited coastal producers. There is a seasonal shift in N/P in the water column of Buttermilk Bay. N/P exceeded the 16∶1 Redfield ratio during midwinter; the remainder of the year N/P fell below 16∶1. This suggests that annual budgets do not provide sufficiently detailed data with which to interpret nutrient-limitation of producers. Further, some idea of water turnover is also needed to evaluate impact of loading rates. Urbanization of watersheds seems to increase loadings to nearshore environments, and to shift the nutrient loadings delivered to coastal waters to relatively high N-to-P ratios, potentially stimulating growth of nitrogen-limited primary producers.

Contributions to the Nutrient Toolbox: Identifying Drivers, Nutrient Sources, and Attribution of Exceedances

EPA Science Inventory

Nutrients are a leading cause of impairments in the United States, and as a result tools are needed to identify drivers of nutrients and response variables (such as chlorophyll a), nutrient sources, and identify causes of exceedances of water quality thresholds. This presentatio...

Groundwater-derived nutrient inputs to the Upper Gulf of Thailand

NASA Astrophysics Data System (ADS)

Burnett, William C.; Wattayakorn, Gullaya; Taniguchi, Makoto; Dulaiova, Henrieta; Sojisuporn, Pramot; Rungsupa, Sompop; Ishitobi, Tomotoshi

2007-01-01

We report here the first direct measurements of nutrient fluxes via groundwater discharge into the Upper Gulf of Thailand. Nutrient and standard oceanographic surveys were conducted during the wet and dry seasons along the Chao Phraya River, Estuary and out into the Upper Gulf of Thailand. Additional measurements in selected near-shore regions of the Gulf included manual and automatic seepage meter deployments, as well as nutrient evaluations of seepage and coastal waters. The river transects characterized the distribution of biogeochemical parameters in this highly contaminated urban environment. Seepage flux measurements together with nutrient analyses of seepage fluids were used to estimate nutrient fluxes via groundwater pathways for comparison to riverine fluxes. Our findings show that disseminated seepage of nutrient-rich mostly saline groundwater into the Upper Gulf of Thailand is significant. Estimated fluxes of dissolved inorganic nitrogen (DIN) supplied via groundwater discharge were 40-50% of that delivered by the Chao Phraya River, inorganic phosphate was 60-70%, and silica was 15-40%. Dissolved organic nitrogen (DON) and phosphorus (DOP) groundwater fluxes were also high at 30-40% and 30-130% of the river inputs, respectively. These observations are especially impressive since the comparison is being made to the river that is the largest source of fresh water into the Gulf of Thailand and flows directly through the megacity of Bangkok with high nutrient loadings from industrial and domestic sources.

The quality of our Nation's waters-Nutrients in the Nation's streams and groundwater, 1992-2004

USGS Publications Warehouse

Dubrovsky, N.M.; Burow, K.R.; Clark, G.M.; Gronberg, J.M.; Hamilton, P.A.; Hitt, K.J.; Mueller, D.K.; Munn, M.D.; Nolan, B.T.; Puckett, L.J.; Rupert, M.G.; Short, T.M.; Spahr, N.E.; Sprague, L.A.; Wilber, W.G.

2010-01-01

National Findings and Their Implications Although the use of artificial fertilizer has supported increasing food production to meet the needs of a growing population, increases in nutrient loadings from agricultural and, to a lesser extent, urban sources have resulted in nutrient concentrations in many streams and parts of aquifers that exceed standards for protection of human health and (or) aquatic life, often by large margins. Do NAWQA findings substantiate national concerns for aquatic and human health? National Water-Quality Assessment (NAWQA) findings indicate that nutrient concentrations in streams and groundwater in basins with significant agricultural or urban development are substantially greater than naturally occurring or ?background? levels. For example, median concentrations of total nitrogen and phosphorus in agricultural streams are about 6 times greater than background levels. Findings also indicate that concentrations in streams routinely were 2 to 10 times greater than regional nutrient criteria recommended by the U.S. Environmental Protection Agency (USEPA) to protect aquatic life. Such large differences in magnitude suggest that significant reductions in sources of nutrients, as well as greater use of land management strategies to reduce the transport of nutrients to streams, are needed to meet recommended criteria for streams draining areas with significant agricultural and urban development. Nitrate concentrations above the Federal drinking-water standard-or Maximum Contaminant Level (MCL)-of 10 milligrams per liter (mg/L, as nit-ogen) are relatively uncommon in samples from streams used for drinking water or from relatively deep aquifers; the MCL is exceeded, however, in more than 20 percent of shallow (less than 100 feet below the water table) domestic wells in agricultural areas. This finding raises concerns for human health in rural agricultural areas where shallow groundwater is used for domestic supply and may warn of future contamination of deeper groundwater pumped from public-supply wells. Are levels of nutrients in water increasing or decreasing? A decadal assessment of trends in concentrations of nitrogen and phosphorus from about 1993 to 2003 shows minimal changes in those concentrations in the majority of studied streams across the Nation, and more upward than downward trends in concentrations at sites with changes. These findings underscore the need for reductions in nutrient inputs or management strategies that would reduce transport of nutrients to streams. Upward trends were evident among all land uses, including those only minimally affected by agricultural and (or) urban development, which suggests that additional protection of some of our Nation's most pristine streams warrants consideration. The median of nitrate concentrations in groundwater from 495 wells also increased significantly from 3.2 to 3.4 mg/L (6 percent) during about the same period, and the proportion of wells with concentrations of nitrate greater than the MCL increased from 16 to 21 percent. Nitrate concentrations in water in deep aquifers are likely to increase during the next decade as shallow groundwater with elevated concentrations moves downward. The potential for future contamination of the deep aquifers requires attention because these aquifers commonly are used for public water supply, and because restoration of groundwater is costly and difficult. Long-term and consistent monitoring of nutrients, improved accounting of nutrient sources, and improved tracking and modeling of climatic and landscape changes will be essential for distinguishing trends in nutrient concentrations, understanding the causes of those trends, and accurately tracking the effectiveness of strategies implemented to manage nutrients.

The quality of our Nation's waters-Nutrients in the Nation's streams and groundwater, 1992-2004

USGS Publications Warehouse

Dubrovsky, Neil M.; Burow, Karen R.; Clark, Gregory M.; Gronberg, JoAnn M.; Hamilton, Pixie A.; Hitt, Kerie J.; Mueller, David K.; Munn, Mark D.; Nolan, Bernard T.; Puckett, Larry J.; Rupert, Michael G.; Short, Terry M.; Spahr, Norman E.; Sprague, Lori A.; Wilber, William G.

2010-01-01

National Findings and Their ImplicationsAlthough the use of artificial fertilizer has supported increasing food production to meet the needs of a growing population, increases in nutrient loadings from agricultural and, to a lesser extent, urban sources have resulted in nutrient concentrations in many streams and parts of aquifers that exceed standards for protection of human health and (or) aquatic life, often by large margins.Do NAWQA findings substantiate national concerns for aquatic and human health?National Water-Quality Assessment (NAWQA) findings indicate that nutrient concentrations in streams and groundwater in basins with significant agricultural or urban development are substantially greater than naturally occurring or “background” levels. For example, median concentrations of total nitrogen and phosphorus in agricultural streams are about 6 times greater than background levels. Findings also indicate that concentrations in streams routinely were 2 to 10 times greater than regional nutrient criteria recommended by the U.S. Environmental Protection Agency (USEPA) to protect aquatic life. Such large differences in magnitude suggest that significant reductions in sources of nutrients, as well as greater use of land management strategies to reduce the transport of nutrients to streams, are needed to meet recommended criteria for streams draining areas with significant agricultural and urban development.Nitrate concentrations above the Federal drinking-water standard—or Maximum Contaminant Level (MCL)—of 10 milligrams per liter (mg/L, as nitrogen) are relatively uncommon in samples from streams used for drinking water or from relatively deep aquifers; the MCL is exceeded, however, in more than 20 percent of shallow (less than 100 feet below the water table) domestic wells in agricultural areas. This finding raises concerns for human health in rural agricultural areas where shallow groundwater is used for domestic supply and may warn of future contamination of deeper groundwater pumped from public‑supply wells.Are levels of nutrients in water increasing or decreasing?A decadal assessment of trends in concentrations of nitrogen and phosphorus from about 1993 to 2003 shows minimal changes in those concentrations in the majority of studied streams across the Nation, and more upward than downward trends in concentrations at sites with changes. These findings underscore the need for reductions in nutrient inputs or management strategies that would reduce transport of nutrients to streams. Upward trends were evident among all land uses, including those only minimally affected by agricultural and (or) urban development, which suggests that additional protection of some of our Nation’s most pristine streams warrants consideration.The median of nitrate concentrations in groundwater from 495 wells also increased significantly from 3.2 to 3.4 mg/L (6 percent) during about the same period, and the proportion of wells with concentrations of nitrate greater than the MCL increased from 16 to 21 percent. Nitrate concentrations in water in deep aquifers are likely to increase during the next decade as shallow groundwater with elevated concentrations moves downward. The potential for future contamination of the deep aquifers requires attention because these aquifers commonly are used for public water supply, and because restoration of groundwater is costly and difficult.Long-term and consistent monitoring of nutrients, improved accounting of nutrient sources, and improved tracking and modeling of climatic and landscape changes will be essential for distinguishing trends in nutrient concentrations, understanding the causes of those trends, and accurately tracking the effectiveness of strategies implemented to manage nutrients.

Stream restoration and sewers impact sources and fluxes of water, carbon, and nutrients in urban watersheds

NASA Astrophysics Data System (ADS)

Pennino, Michael J.; Kaushal, Sujay S.; Mayer, Paul M.; Utz, Ryan M.; Cooper, Curtis A.

2016-08-01

An improved understanding of sources and timing of water, carbon, and nutrient fluxes associated with urban infrastructure and stream restoration is critical for guiding effective watershed management globally. We investigated how sources, fluxes, and flowpaths of water, carbon (C), nitrogen (N), and phosphorus (P) shift in response to differences in urban stream restoration and sewer infrastructure. We compared an urban restored stream with two urban degraded streams draining varying levels of urban development and one stream with upland stormwater management systems over a 3-year period. We found that there was significantly decreased peak discharge in response to precipitation events following stream restoration. Similarly, we found that the restored stream showed significantly lower (p < 0.05) monthly peak runoff (9.4 ± 1.0 mm day-1) compared with two urban degraded streams (ranging from 44.9 ± 4.5 to 55.4 ± 5.8 mm day-1) draining higher impervious surface cover, and the stream-draining stormwater management systems and less impervious surface cover in its watershed (13.2 ± 1.9 mm day-1). The restored stream exported most carbon, nitrogen, and phosphorus at relatively lower streamflow than the two more urban catchments, which exported most carbon and nutrients at higher streamflow. Annual exports of total carbon (6.6 ± 0.5 kg ha-1 yr-1), total nitrogen (4.5 ± 0.3 kg ha-1 yr-1), and total phosphorus (161 ± 15 kg ha-1 yr-1) were significantly lower in the restored stream compared to both urban degraded streams (p < 0.05), but statistically similar to the stream draining stormwater management systems, for N exports. However, nitrate isotope data suggested that 55 ± 1 % of the nitrate in the urban restored stream was derived from leaky sanitary sewers (during baseflow), statistically similar to the urban degraded streams. These isotopic results as well as additional tracers, including fluoride (added to drinking water) and iodide (contained in dietary salt), suggested that groundwater contamination was a major source of urban nutrient fluxes, which has been less considered compared to upland sources. Overall, leaking sewer pipes are a problem globally and our results suggest that combining stream restoration with restoration of aging sewer pipes can be critical to more effectively minimizing urban nonpoint nutrient sources. The sources, fluxes, and flowpaths of groundwater should be prioritized in management efforts to improve stream restoration by locating hydrologic hot spots where stream restoration is most likely to succeed.

Modeling Nutrient Loading to Watersheds in the Great Lakes Basin: A Detailed Source Model at the Regional Scale

NASA Astrophysics Data System (ADS)

Luscz, E.; Kendall, A. D.; Martin, S. L.; Hyndman, D. W.

2011-12-01

Watershed nutrient loading models are important tools used to address issues including eutrophication, harmful algal blooms, and decreases in aquatic species diversity. Such approaches have been developed to assess the level and source of nutrient loading across a wide range of scales, yet there is typically a tradeoff between the scale of the model and the level of detail regarding the individual sources of nutrients. To avoid this tradeoff, we developed a detailed source nutrient loading model for every watershed in Michigan's lower peninsula. Sources considered include atmospheric deposition, septic tanks, waste water treatment plants, combined sewer overflows, animal waste from confined animal feeding operations and pastured animals, as well as fertilizer from agricultural, residential, and commercial sources and industrial effluents . Each source is related to readily-available GIS inputs that may vary through time. This loading model was used to assess the importance of sources and landscape factors in nutrient loading rates to watersheds, and how these have changed in recent decades. The results showed the value of detailed source inputs, revealing regional trends while still providing insight to the existence of variability at smaller scales.

Efficacies of designer biochars in improving biomass and nutrient uptake of winter wheat grown in a hard setting subsoil layer.

PubMed

Sigua, G C; Novak, J M; Watts, D W; Johnson, M G; Spokas, K

2016-01-01

In the Coastal Plains region of the United States, the hard setting subsoil layer of Norfolk soils results in low water holding capacity and nutrient retention, which often limits root development. In this region, the Norfolk soils are under intensive crop production that further depletes nutrients and reduces organic carbon (C). Incorporation of pyrolyzed organic residues or "biochars" can provide an alternative recalcitrant C source. However, biochar quality and effect can be inconsistent and different biochars react differently in soils. We hypothesized that addition of different designer biochars will have variable effects on biomass and nutrient uptake of winter wheat. The objective of this study was to investigate the effects of designer biochars on biomass productivity and nutrient uptake of winter wheat (Triticum aestivum L.) in a Norfolk's hard setting subsoil layer. Biochars were added to Norfolk's hard setting subsoil layer at the rate of 40 Mg ha(-1). The different sources of biochars were: plant-based (pine chips, PC); animal-based (poultry litter, PL); 50:50 blend (50% PC:50% PL); 80:20 blend (80% PC:20% PL); and hardwood (HW). Aboveground and belowground biomass and nutrient uptake of winter wheat varied significantly (p⩽0.0001) with the different designer biochar applications. The greatest increase in the belowground biomass of winter wheat over the control was from 80:20 blend of PC:PL (81%) followed by HW (76%), PC (59%) and 50:50 blend of PC:PL (9%). However, application of PL resulted in significant reduction of belowground biomass by about 82% when compared to the control plants. The average uptake of P, K, Ca, Mg, Na, Al, Fe, Cu and Zn in both the aboveground and belowground biomass of winter wheat varied remarkably with biochar treatments. Overall, our results showed promising significance for the treatment of a Norfolk's hard setting subsoil layer since designer biochars did improve both aboveground/belowground biomass and nutrient uptake of winter wheat. Published by Elsevier Ltd.

Nutrient exports from watersheds with varying septic system densities in the North Carolina Piedmont.

PubMed

Iverson, G; Humphrey, C P; O'Driscoll, M A; Sanderford, C; Jernigan, J; Serozi, B

2018-04-01

Septic systems (SSs) have been shown to be a significant source of nitrogen and phosphorus to nutrient-sensitive coastal surface and groundwaters. However, few published studies have quantified the effects of SSs on nutrient inputs to water supply watersheds in the Piedmont region of the USA. This region consists of rolling hills at the surface underlain by clayey soils. There are nearly 1 million SSs in this region, which accounts for approximately 50% of all SSs in North Carolina. The goal of this study was to determine if significant differences in nutrient concentrations and exports exist between Piedmont watersheds with different densities of SSs. Water quality was assessed in watersheds with SSs (n = 11) and a sewer and a forested watershed, which were designated as controls. Stream flow and environmental readings were recorded and water samples were collected from the watersheds from January 2015-December 2016. Additional samples were collected from sand filter watersheds in April 2015-March 2016 to compare to septic and control watersheds. Samples were analyzed for total dissolved nitrogen (TDN) and orthophosphate (PO 4 -P). Results indicated that watersheds served by a high-density (HD) of SSs (4.9 kg-N yr -1 ha -1 ; 0.2 kg-P yr -1 ha -1 ) exported more than double the median masses of TDN and PO 4 -P, respectively, relative to low-density (1.0 kg-N yr -1 ha -1 ; <0.1 kg-P yr -1 ha -1 ) and control watersheds (1.4 kg-N yr -1 ha -1 ; <0.1 kg-P yr -1 ha -1 ) during baseflow. Isotopic analysis indicated that wastewater was the most likely source of nitrate-N in HD watersheds. In all other watersheds, isotopic results suggested non-wastewater sources as the dominant nitrate-N provider. These findings indicated that SS density was a significant factor in the delivery of septic-derived nutrients to these nutrient-sensitive, water supply watersheds of the North Carolina Piedmont. Copyright © 2018 Elsevier Ltd. All rights reserved.

Soil carbon fractions under maize-wheat system: effect of tillage and nutrient management.

PubMed

Sandeep, S; Manjaiah, K M; Pal, Sharmistha; Singh, A K

2016-01-01

Soil organic carbon plays a major role in sustaining agroecosystems and maintaining environmental quality as it acts as a major source and sink of atmospheric carbon. The present study aims to assess the impact of agricultural management practices on soil organic carbon pools in a maize-wheat cropping system of Indo-Gangetic Plains, India. Soil samples from a split plot design with two tillage systems (bed planting and conventional tillage) and six nutrient treatments (T1 = control, T2 = 120 kg urea-N ha(-1), T3 = T2 (25 % N substituted by FYM), T4 = T2 (25 % N substituted by sewage sludge), T5 = T2 + crop residue, T6 = 100 % organic source (50 % FYM + 25 % biofertilizer + 25 % crop residue) were used for determining the organic carbon pools. Results show that there was a significant improvement in Walkley and Black carbon in soil under integrated and organic nutrient management treatments. KMnO4-oxidizable carbon content of soil varied from 0.63 to 1.50 g kg(-1) in soils and was found to be a better indicator for monitoring the impact of agricultural management practices on quality of soil organic carbon than microbial biomass carbon. Tillage and its interaction were found to significantly influence only those soil organic carbon fractions closely associated with aggregate stability viz, labile polysaccharides and glomalin. The highest amount of C4-derived carbon was found to be in plots receiving recommended doses of N as urea (29 %) followed by control plots (25 %). The carbon management index ranged between 82 to 195 and was better in integrated nutrient sources than ones receiving recommended doses of nutrients through mineral fertilizers alone.

Submarine groundwater discharge as an important nutrient source influencing nutrient structure in coastal water of Daya Bay, China

NASA Astrophysics Data System (ADS)

Wang, Xuejing; Li, Hailong; Zheng, Chunmiao; Yang, Jinzhong; Zhang, Yan; Zhang, Meng; Qi, Zhanhui; Xiao, Kai; Zhang, Xiaolang

2018-03-01

As an important nutrient source for coastal waters, submarine groundwater discharge (SGD) has long been largely ignored in Daya Bay, China. In this study, we estimate the fluxes of SGD and associated nutrients into this region using a 224Ra mass balance model and assess the contribution/importance of nutrients by SGD, benthic sediments, local rivers, and atmospheric deposition. The results of 224Ra mass balance show that the estimated SGD ranges from (2.76 ± 1.43) × 106 m3/d to (1.03 ± 0.53) × 107 m3/d with an average of (6.32 ± 2.42) × 106 m3/d, about 16 times the total discharge rate of local rivers. The nutrient loading from SGD is estimated to be (1.05-1.99) × 105 mol/d for NO3-N, (4.04-12.16) × 103 mol/d for DIP, and (3.54-11.35) × 105 mol/d for Si. Among these considered nutrient sources, we find that SGD is the primary source for Si and NO3-N, contributing 68% and 42% of all considered sources, respectively. The atmospheric NO3-N flux is comparable to that from SGD. The local rivers are the most important source for DIP, contributing 75% of all considered sources. SGD with high N:P ratio (NO3-N/DIP) of 37.0 delivers not only a large quantity of nutrients, but also changes nutrient structure in coastal water. Based on a DIP budget, primary productivity is evaluated to be 54-73 mg C/m2 d, in which SGD accounts for approximately 30% of total production. This study indicates that SGD is a key source of nutrients to coastal waters and may cause an obvious change of primary production and nutrient structure in Daya Bay.

Research to Inform Nutrient Thresholds and Prioritization of ...

EPA Pesticide Factsheets

The information in this presentation focuses on SSWR's 4.02 project, which will advance the science needed to inform decisions to prioritize watersheds and nutrient sources for nutrient management and define appropriate nutrient levels for the nation’s waters, two important elements of EPA’s framework for managing nutrient pollution. The information in this presentation focuses on SSWR's 4.02 project, which will advance the science needed to inform decisions to prioritize watersheds and nutrient sources for nutrient management and define appropriate nutrient levels for the nation’s waters, two important elements of EPA’s framework for managing nutrient pollution.

Impacts of urban wastewater discharge on seagrass meadows ( Zostera noltii)

NASA Astrophysics Data System (ADS)

Cabaço, Susana; Machás, Raquel; Vieira, Vasco; Santos, Rui

2008-06-01

The abiotic disturbance of urban wastewater discharge and its effects in the population structure, plant morphology, leaf nutrient content, epiphyte load and macroalgae abundance of Zostera noltii meadows were investigated in Ria Formosa coastal lagoon, southern Portugal using both univariate and multivariate analysis. Four sites were assessed, on a seasonal basis, along a gradient from a major Waste Water Treatment Works (WWTW) discharge to a main navigation channel. The wastewater discharge caused an evident environmental disturbance through the nutrient enrichment of the water and sediment, particularly of ammonium. Zostera noltii of the sites closest to the nutrient source showed higher leaf N content, clearly reflecting the nitrogen load. The anthropogenic nutrient enrichment resulted in higher biomass, and higher leaf and internode length, except for the meadow closest to the wastewater discharge (270 m). The high ammonium concentration (158-663 μM) in the water at this site resulted in the decrease of biomass, and both the leaf and internode length, suggesting a toxic effect on Z. noltii. The higher abundance of macroalgae and epiphytes found in the meadow closest to the nutrient source may also affect the species negatively. Shoot density was higher at the nutrient-undisturbed site. Two of the three abiotic processes revealed by Principal Component Analysis were clearly related to the WWTW discharge, a contrast between water column salinity and nutrient concentration and a sediment contrast between both porewater nutrients and temperature and redox potential. A multiple regression analysis showed that these abiotic processes had a significant effect on the biomass-density dynamics of meadows and on the overall size of Z. noltii plants, respectively. Results show that the wastewater discharge is an important source of environmental disturbance and nutrients availability in Ria Formosa lagoon affecting the population structure, morphology and N content of Z. noltii. This impact is spatially restricted to areas up to 600 m distant from the WWTW discharge, probably due to the high water renewal of the lagoon.

Complete nutrient content of four species of commercially available feeder insects fed enhanced diets during growth.

PubMed

Finke, Mark D

2015-11-01

Commercially raised feeder insects used to feed captive insectivores are a good source of many nutrients but are deficient in several key nutrients. Current methods used to supplement insects include dusting and gut-loading. Here, we report on the nutrient composition of four species of commercially raised feeder insects fed a special diet to enhance their nutrient content. Crickets, mealworms, superworms, and waxworms were analyzed for moisture, crude protein, fat, ash, acid detergent fiber, total dietary fiber, minerals, amino acids, fatty acids, vitamins, taurine, carotenoids, inositol, and cholesterol. All four species contained enhanced levels of vitamin E and omega 3 fatty acids when compared to previously published data for these species. Crickets, superworms, and mealworms contained β-carotene although using standard conversion factors only crickets and superworms would likely contain sufficient vitamin A activity for most species of insectivores. Waxworms did not contain any detectable β-carotene but did contain zeaxanthin which they likely converted from dietary β-carotene. All four species contained significant amounts of both inositol and cholesterol. Like previous reports all insects were a poor source of calcium and only superworms contained vitamin D above the limit of detection. When compared to the nutrient requirements as established by the NRC for growing rats or poultry, these species were good sources of most other nutrients although the high fat and low moisture content of both waxworms and superworms means when corrected for energy density these two species were deficient in more nutrients than crickets or mealworms. These data show the value of modifying the diet of commercially available insects as they are growing to enhance their nutrient content. They also suggest that for most insectivores properly supplemented lower fat insects such as crickets, or smaller mealworms should form the bulk of the diet. © 2015 The Authors. Zoo Biology published by Wiley Periodicals, Inc.

Wastewater treatment plant effluent introduces recoverable shifts in microbial community composition in urban streams

NASA Astrophysics Data System (ADS)

Ledford, S. H.; Price, J. R.; Ryan, M. O.; Toran, L.; Sales, C. M.

2017-12-01

New technologies are allowing for intense scrutiny of the impact of land use on microbial communities in stream networks. We used a combination of analytical chemistry, real-time polymerase chain reaction (qPCR) and targeted amplicon sequencing for a preliminary study on the impact of wastewater treatment plant effluent discharge on urban streams. Samples were collected on two dates above and below treatment plants on the Wissahickon Creek, and its tributary, Sandy Run, in Montgomery County, PA, USA. As expected, effluent was observed to be a significant source of nutrients and human and non-specific fecal associated taxa. There was an observed increase in the alpha diversity at locations immediately below effluent outflows, which contributed many taxa involved in wastewater treatment processes and nutrient cycling to the stream's microbial community. Unexpectedly, modeling of microbial community shifts along the stream was not controlled by concentrations of measured nutrients. Furthermore, partial recovery, in the form of decreasing abundances of bacteria and nutrients associated with wastewater treatment plant processes, nutrient cycling bacteria, and taxa associated with fecal and sewage sources, was observed between effluent sources. Antecedent moisture conditions impacted overall microbial community diversity, with higher diversity occurring after rainfall. These findings hint at resilience in stream microbial communities to recover from wastewater treatment plant effluent and are vital to understanding the impacts of urbanization on microbial stream communities.

Ultrasonic waste activated sludge disintegration for recovering multiple nutrients for biofuel production.

PubMed

Xie, Guo-Jun; Liu, Bing-Feng; Wang, Qilin; Ding, Jie; Ren, Nan-Qi

2016-04-15

Waste activated sludge is a valuable resource containing multiple nutrients, but is currently treated and disposed of as an important source of pollution. In this work, waste activated sludge after ultrasound pretreatment was reused as multiple nutrients for biofuel production. The nutrients trapped in sludge floc were transferred into liquid medium by ultrasonic disintegration during first 30 min, while further increase of pretreatment time only resulted in slight increase of nutrients release. Hydrogen production by Ethanoligenens harbinense B49 from glucose significantly increased with the concentration of ultrasonic sludge, and reached maximum yield of 1.97 mol H2/mol glucose at sludge concentration of 7.75 g volatile suspended solids/l. Without addition of any other chemicals, waste molasses rich in carbohydrate was efficiently turned into hydrogen with yield of 189.34 ml H2/g total sugar by E. harbinense B49 using ultrasonic sludge as nutrients. The results also showed that hydrogen production using pretreated sludge as multiple nutrients was higher than those using standard nutrients. Acetic acid produced by E. harbinense B49 together with the residual nutrients in the liquid medium were further converted into hydrogen (271.36 ml H2/g total sugar) by Rhodopseudomonas faecalis RLD-53 through photo fermentation, while ethanol was the sole end product with yield of 220.26 mg/g total sugar. Thus, pretreated sludge was an efficient nutrients source for biofuel production, which could replace the standard nutrients. This research provided a novel strategy to achieve environmental friendly sludge disposal and simultaneous efficient biofuel recovery from organic waste. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ethnic disparities among food sources of energy and nutrients of public health concern and nutrients to limit in adults in the United States: NHANES 2003-2006.

PubMed

O'Neil, Carol E; Nicklas, Theresa A; Keast, Debra R; Fulgoni, Victor L

2014-01-01

Identification of current food sources of energy and nutrients among US non-Hispanic whites (NHW), non-Hispanic blacks (NHB), and Mexican American (MA) adults is needed to help with public health efforts in implementing culturally sensitive and feasible dietary recommendations. The objective of this study was to determine the food sources of energy and nutrients to limit [saturated fatty acids (SFA), added sugars, and sodium] and nutrients of public health concern (dietary fiber, vitamin D, calcium, and potassium) by NHW, NHB, and MA adults. This was a cross-sectional analysis of a nationally representative sample of NWH (n=4,811), NHB (2,062), and MA (n=1,950) adults 19+ years. The 2003-2006 NHANES 24-h recall (Day 1) dietary intake data were analyzed. An updated USDA Dietary Source Nutrient Database was developed using current food composition databases. Food grouping included ingredients from disaggregated mixtures. Mean energy and nutrient intakes from food sources were sample-weighted. Percentages of total dietary intake contributed from food sources were ranked. Multiple differences in intake among ethnic groups were seen for energy and all nutrients examined. For example, energy intake was higher in MA as compared to NHB; SFA, added sugars, and sodium intakes were higher in NHW than NHB; dietary fiber was highest in MA and lowest in NHB; vitamin D was highest in NHW; calcium was lowest in NHB; and potassium was higher in NHW as compared to NHB. Food sources of these nutrients also varied. Identification of intake of nutrients to limit and of public health concern can help health professionals implement appropriate dietary recommendations and plan interventions that are ethnically appropriate.

Spatial hydrological flow processes, water quality, sediment and vegetation community distributions in a natural floodplain fen - implication for the Flood Pulse Concept

NASA Astrophysics Data System (ADS)

Keizer, Floris; Schot, Paul; Wassen, Martin; Kardel, Ignacy; Okruszko, Tomasz

2017-04-01

We studied spatial patterns in inundation water quality, sediment and vegetation distribution in a floodplain fen in Poland to map interacting peatland hydrological processes. Using PCA and K-means cluster analysis, we identified four water types, related to river water inundation, discharge of clean and polluted groundwater, and precipitation and snowmelt dilution. Spatially, these hydrochemical water types are related to known water sources in the floodplain and occupy distinctive zones. River water is found along the river, clean and polluted groundwater at the valley margins and groundwater diluted with precipitation and snowmelt water in the central part of the floodplain. This implies that, despite the floodplain being completely inundated, nutrient input from river flooding occurs only in a relatively narrow zone next to the river. Our findings question the relevance of the edge of inundation, as presented in the Flood Pulse Concept, as delineating the zone of input and turnover of nutrients. Secondly, we studied rich-fen and freshwater vegetation community distributions in relation to the presented inundation water quality types. We successfully determined inundation water quality preference for 14 out of 17 studied rich-fen and freshwater communities in the floodplain. Spatial patterns in preference show vegetation with attributed river water preference to occur close to the river channel, with increasing distance to the river followed by communities with no preference, diluted groundwater preference in the central part, and clean and polluted groundwater preference at the valley margins. In inundation water, nutrients are known to be transported mainly as attached to sediment, besides in dissolved state. This means that in the zone where sediment deposition occurs, nutrient input can be a relevant contribution to the nutrient input of the floodplain. We found a significant decrease in sediment-attached nutrient deposition with distance from the river. Sediment-attached nutrients correlated better to aboveground standing biomass than dissolved nutrients. These findings further reduce the spatial zone where significant nutrient input is influenced by transport from the river, compared to the zone influenced by dissolved nutrients. Our findings indicate the need for a revision of the Flood Pulse Concept for temperate river with multiple water sources, as peatland hydrological processes significantly influence spatial floodplain vegetation distribution.

Food acquisition habits, nutrient intakes, and anthropometric data of Havasupai adults.

PubMed

Vaughan, L A; Benyshek, D C; Martin, J F

1997-11-01

To describe the dietary patterns, anthropometric data, and food sources of Havasupai adults (> or = 18 years old) and determine the effect of age and gender. Dietary intakes (one 24-hour recall), anthropometric measures (body mass index [BMI], waist-to-hip ratio [WHR]) and demographic data, including sites of food purchases, were obtained. Food sources of selected nutrients were calculated from diet recalls. 92 adults (60 women, 32 men) from the Havasupai Reservation, Supai, Ariz. Descriptive statistics were generated for demographic data. Nutrient intakes, BMI, and WHR were compared across gender and age groups ("Younger" [18 to 59 years old] vs "older" [> or = 60 years old]) by one-way analysis of variance. Two-tailed t tests identified significant differences in selected food practices by age group. Diets were moderately high in fat (35% of energy), saturated fat (12%), and sugar (14%); intakes of zinc, calcium, vitamin A, vitamin B-6, and folate were frequently inadequate (less than two thirds of the Recommended Dietary Allowance). Of the 92 subjects, 76 (83%) were obese (BMI > or = 27). Fifty-four of the 60 women (90%) and 24 of the 32 men (75%) exhibited abdominal obesity (no age effect). Thirty-nine of the subjects (42%) consumed at least one food item purchased off the reservation on the day of the recall; the remaining 53 subjects (58%) consumed only food purchased or acquired on the reservation. Older Havasupai were significantly more dependent on the tribal store and other village food sources than were younger adults. Food sources of key nutrients did not differ by age or gender. The dietary patterns of isolated populations may be shaped by the unique limitations of their food sources as well as by factors such as age and gender. Individual and community-wide efforts to improve nutrient intakes and food patterns must recognize these geographic limitations. For populations such as the Havasupai, cooperative marketing and health promotion efforts between tribal officials, health care providers, and managers of the cafe and tribal store could improve the availability and consumption of a wider range of health-promoting foods.

The Effects of Different External Carbon Sources on Nitrous Oxide Emissions during Denitrification in Biological Nutrient Removal Processes

NASA Astrophysics Data System (ADS)

Hu, Xiang; Zhang, Jing; Hou, Hongxun

2018-01-01

The aim of this study was to investigate the effects of two different external carbon sources (acetate and ethanol) on the nitrous oxide (N2O) emissions during denitrification in biological nutrient removal processes. Results showed that external carbon source significantly influenced N2O emissions during the denitrification process. When acetate served as the external carbon source, 0.49 mg N/L and 0.85 mg N/L of N2O was produced during the denitrificaiton processes in anoxic and anaerobic/anoxic experiments, giving a ratio of N2O-N production to TN removal of 2.37% and 4.96%, respectively. Compared with acetate, the amount of N2O production is negligible when ethanol used as external carbon addition. This suggested that ethanol is a potential alternative external carbon source for acetate from the point of view of N2O emissions.

The Anthropogenic Effects of Hydrocarbon Inputs to Coastal Seas: Are There Potential Biogeochemical Impacts?

NASA Astrophysics Data System (ADS)

Anderson, M. R.; Rivkin, R. B.

2016-02-01

Petroleum hydrocarbon discharges related to fossil fuel exploitation have the potential to alter microbial processes in the upper ocean. While the ecotoxicological effects of such inputs are commonly evaluated, the potential for eutrophication from the constituent organic and inorganic nutrients has been largely ignored. Hydrocarbons from natural seeps and anthropogenic sources represent a measurable source of organic carbon for surface waters. The most recent (1989-1997) estimate of average world-wide input of hydrocarbons to the sea is 1.250 x 1012 g/yr ≈ 1.0 x 1012g C/year. Produced water from offshore platforms is the largest waste stream from oil and gas exploitation and contributes significant quantities of inorganic nutrients such as N, P and Fe. In coastal areas where such inputs are a significant source of these nutrients, model studies show the potential to shift production toward smaller cells and net heterotrophy. The consequences of these nutrient sources for coastal systems and semi enclosed seas are complex and difficult to predict, because (1) there is a lack of comprehensive data on inputs and in situ concentrations and (2) the is no conceptual or quantitative framework to consider their effects on ocean biogeochemical processes. Here we use examples from the North Sea (produced water discharges 1% total riverine input and NH4 3% of the annual riverine nitrogen load), the South China Sea (total petroleum hydrocarbons = 10-1750 μg/l in offshore waters), and the Gulf of Mexico (seeps = 76-106 x 109 gC/yr, Macondo blowout 545 x 109 gC) to demonstrate how hydrocarbon and produced water inputs can influence basin scale biogeochemical and ecosystem processes and to propose a framework to consider these effects on larger scales.

New insights into carbon acquisition and exchanges within the coral–dinoflagellate symbiosis under NH4+ and NO3− supply

PubMed Central

Ezzat, Leïla; Maguer, Jean-François; Grover, Renaud; Ferrier-Pagès, Christine

2015-01-01

Anthropogenic nutrient enrichment affects the biogeochemical cycles and nutrient stoichiometry of coastal ecosystems and is often associated with coral reef decline. However, the mechanisms by which dissolved inorganic nutrients, and especially nitrogen forms (ammonium versus nitrate) can disturb the association between corals and their symbiotic algae are subject to controversial debate. Here, we investigated the coral response to varying N : P ratios, with nitrate or ammonium as a nitrogen source. We showed significant differences in the carbon acquisition by the symbionts and its allocation within the symbiosis according to nutrient abundance, type and stoichiometry. In particular, under low phosphate concentration (0.05 µM), a 3 µM nitrate enrichment induced a significant decrease in carbon fixation rate and low values of carbon translocation, compared with control conditions (N : P = 0.5 : 0.05), while these processes were significantly enhanced when nitrate was replaced by ammonium. A combined enrichment in ammonium and phosphorus (N : P = 3 : 1) induced a shift in nutrient allocation to the symbionts, at the detriment of the host. Altogether, these results shed light into the effect of nutrient enrichment on reef corals. More broadly, they improve our understanding of the consequences of nutrient loading on reef ecosystems, which is urgently required to refine risk management strategies. PMID:26203006

21 CFR 101.54 - Nutrient content claims for “good source,” “high,” “more,” and “high potency.”

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Nutrient content claims for âgood source,â âhigh,â âmore,â and âhigh potency.â 101.54 Section 101.54 Food and Drugs FOOD AND DRUG ADMINISTRATION... Requirements for Nutrient Content Claims § 101.54 Nutrient content claims for “good source,” “high,” “more...

21 CFR 101.54 - Nutrient content claims for “good source,” “high,” “more,” and “high potency.”

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Nutrient content claims for âgood source,â âhigh,â âmore,â and âhigh potency.â 101.54 Section 101.54 Food and Drugs FOOD AND DRUG ADMINISTRATION... Requirements for Nutrient Content Claims § 101.54 Nutrient content claims for “good source,” “high,” “more...

21 CFR 101.54 - Nutrient content claims for “good source,” “high,” “more,” and “high potency.”

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Nutrient content claims for âgood source,â âhigh,â âmore,â and âhigh potency.â 101.54 Section 101.54 Food and Drugs FOOD AND DRUG ADMINISTRATION... Requirements for Nutrient Content Claims § 101.54 Nutrient content claims for “good source,” “high,” “more...

Evaluation of agricultural best-management practices in the Conestoga River headwaters, Pennsylvania; effects of nutrient management on water quality in the Little Conestoga Creek headwaters, 1983-89

USGS Publications Warehouse

Koerkle, E.H.; Fishel, D.K.; Brown, M.J.; Kostelnik, K.M.

1996-01-01

Water quality in the headwaters of the Little Conestoga Creek, Lancaster County, Pa., was investigated from April 1986 through September 1989 to determine possible effects of agricultural nutrient management on water quality. Nutrient management, an agricultural Best-Management Practice, was promoted in the 5.8-square-mile watershed by the U.S. Department of Agriculture Rural Clean Water Program. Nonpoint-source- agricultural contamination was evident in surface water and ground water in the watershed; the greatest contamination was in areas underlain by carbonate rock and with intensive row-crop and animal production. Initial implementation of nutrient management covered about 30 percent of applicable land and was concentrated in the Nutrient-Management Subbasin. By 1989, nutrient management covered about 45 percent of the entire Small Watershed, about 85 percent of the Nutrient- Management Subbasin, and less than 10 percent of the Nonnutrient-Management Subbasin. The number of farms implementing nutrient management increased from 14 in 1986 to 25 by 1989. Nutrient applications to cropland in the Nutrient- Management Subbasin decreased by an average of 35 percent after implementation. Comparison of base- flow surface-water quality from before and after implementation suggests that nutrient management was effective in slowing or reversing increases in concentrations of dissolved nitrate plus nitrite in the Nutrient-Management Subbasin. Although not statistically significant, the Mann-Whitney step-trend coefficient for the Nutrient-Management Subbasin was 0.8 milligram per liter, whereas trend coefficients for the Nonnutrient-Management Subbasin and the Small Watershed were 0.4 and 1.4 milligrams per liter, respectively, for the period of study. Analysis of covariance comparison of concurrent concentrations from the two sub- basins showed a significant decrease in concen- trations from the Nutrient-Management Subbasin compared to the Nonnutrient-Management Subbasin. The small, positive effect of nutrient management on base-flow water quality should be interpreted with caution. Lack of statistical significance for most tests, short-term variation in climate and agricultural activities, unknown ground-water flow rates, and insufficient agricultural-activity data for farms outside of the Nutrient-Management Subbasin were potential problems. A regression model relating nutrient applications to concen- trations of dissolved nitrate plus nitrite showed no significant explanatory relation.

Nitrogen speciation and phosphorus fractionation dynamics in a lowland Chalk catchment.

PubMed

Yates, C A; Johnes, P J

2013-02-01

A detailed analysis of temporal and spatial trends in nitrogen (N) speciation and phosphorus (P) fractionation in the Wylye, a lowland Chalk sub-catchment of the Hampshire Avon, UK is presented, identifying the sources contributing to nutrient enrichment, and temporal variability in the fractionation of nutrients in transit from headwaters to lower reaches of the river. Samples were collected weekly from ten monitoring stations with daily sampling at three further sites over one year, and monthly inorganic N and total reactive P (TRP) concentrations at three of the ten weekly monitoring stations over a ten year period are also presented. The data indicate significant daily and seasonal variation in nutrient fractionation in the water column, resulting from plant uptake of dissolved organic and inorganic nutrient fractions in the summer months, increased delivery of both N and P from diffuse sources in the autumn to winter period and during high flow events, and lack of dilution of point source discharges to the Wylye from septic tank, small package Sewage Treatment Works (STW) and urban Waste Water Treatment Works (WwTW) during the summer low flow period. Weekly data show that contributing source areas vary along the river with headwater N and P strongly influenced by diffuse inorganic N and particulate P fluxes, and SRP and organic-rich point source contributions from STW and WwTW having a greater influence in the lower reaches. Long-term data show a decrease in TRP concentrations at all three monitoring stations, with the most pronounced decrease occurring downstream from Warminster WwTW, following the introduction of P stripping at the works in 2001. Inorganic N demonstrates no statistically significant change over the ten year period of record in the rural headwaters, but an increase in the lower reaches downstream from the WwTW which may be due to urban expansion in the lower catchment. Copyright © 2012 Elsevier B.V. All rights reserved.

Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense.

PubMed

Townsend, D W; McGillicuddy, D J; Thomas, M A; Rebuck, N R

2014-05-01

We report here the results of ten oceanographic survey cruises carried out in the Gulf of Maine - Georges Bank region of the Northwest Atlantic during the late spring to summer period in 2007, 2008 and 2010, for which we examine and characterize relationships among dissolved inorganic nutrient fields, water mass dynamics and cell densities of the toxic dinoflagellate Alexandrium fundyense . Nutrients are supplied to continental shelf waters of the Gulf of Maine - Georges Bank region by inflows of deep offshore water masses; once in the Gulf they are transported with the residual circulation and mix with surface waters, both in the Gulf and on the Bank. Those fluxes of offshore water masses and their nutrient loads are the major source of nutrients for phytoplankton production in the region, including annual blooms of A. fundyense in the Gulf and on Georges Bank. This much is already known. We suggest here that the locations and magnitude of A. fundyense blooms are controlled in part by variable nutrient fluxes to the interior Gulf of Maine from offshore, and, those interior Gulf of Maine waters are, in turn, the main nutrient source to Georges Bank, which are brought onto the Bank by tidal pumping on the Northern Flank. We present evidence that nitrate is the initial form of nitrogenous nutrient for A. fundyense blooms, but it is quickly depleted to limiting concentrations of less than 0.5 μM, at which time continued growth and maintenance of the population is likely fueled by recycled ammonium. We also show that phosphate may be the limiting nutrient over much of Georges Bank in summer, allowing recycled ammonium concentrations to increase. Our temperature-salinity analyses reveal spatial and temporal (seasonal and interannual) variability in the relative proportions of two deep source waters that enter the Gulf of Maine at depth through the Northeast Channel: Warm Slope Water (WSW) and Labrador Slope Water (LSW). Those two source waters are known to vary in their nutrient loads, with nitrate concentrations about 50% higher in WSW than LSW, for example, and as such the proportions of these two water masses to one another are important determinants of the overall nutrient loads in the interior Gulf. In addition to these deep slope water fluxes, we show evidence here of episodic fluxes of relatively fresh and low-nutrient shelf waters from the Nova Scotian Shelf, which enter the Gulf in pulses at depths between the surface and approximately 150 m, displacing deep slope waters, and consequently they significantly dilute the Gulf's interior waters, reducing nutrient concentrations and, in turn, affect the magnitude of A. fundyense blooms.

Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense

PubMed Central

Townsend, D.W.; McGillicuddy, D.J.; Thomas, M.A.; Rebuck, N.R.

2015-01-01

We report here the results of ten oceanographic survey cruises carried out in the Gulf of Maine - Georges Bank region of the Northwest Atlantic during the late spring to summer period in 2007, 2008 and 2010, for which we examine and characterize relationships among dissolved inorganic nutrient fields, water mass dynamics and cell densities of the toxic dinoflagellate Alexandrium fundyense. Nutrients are supplied to continental shelf waters of the Gulf of Maine - Georges Bank region by inflows of deep offshore water masses; once in the Gulf they are transported with the residual circulation and mix with surface waters, both in the Gulf and on the Bank. Those fluxes of offshore water masses and their nutrient loads are the major source of nutrients for phytoplankton production in the region, including annual blooms of A. fundyense in the Gulf and on Georges Bank. This much is already known. We suggest here that the locations and magnitude of A. fundyense blooms are controlled in part by variable nutrient fluxes to the interior Gulf of Maine from offshore, and, those interior Gulf of Maine waters are, in turn, the main nutrient source to Georges Bank, which are brought onto the Bank by tidal pumping on the Northern Flank. We present evidence that nitrate is the initial form of nitrogenous nutrient for A. fundyense blooms, but it is quickly depleted to limiting concentrations of less than 0.5 μM, at which time continued growth and maintenance of the population is likely fueled by recycled ammonium. We also show that phosphate may be the limiting nutrient over much of Georges Bank in summer, allowing recycled ammonium concentrations to increase. Our temperature-salinity analyses reveal spatial and temporal (seasonal and interannual) variability in the relative proportions of two deep source waters that enter the Gulf of Maine at depth through the Northeast Channel: Warm Slope Water (WSW) and Labrador Slope Water (LSW). Those two source waters are known to vary in their nutrient loads, with nitrate concentrations about 50% higher in WSW than LSW, for example, and as such the proportions of these two water masses to one another are important determinants of the overall nutrient loads in the interior Gulf. In addition to these deep slope water fluxes, we show evidence here of episodic fluxes of relatively fresh and low-nutrient shelf waters from the Nova Scotian Shelf, which enter the Gulf in pulses at depths between the surface and approximately 150 m, displacing deep slope waters, and consequently they significantly dilute the Gulf's interior waters, reducing nutrient concentrations and, in turn, affect the magnitude of A. fundyense blooms. PMID:26028824

Food sources of energy and nutrients in Finnish girls and boys 6-8 years of age - the PANIC study.

PubMed

Eloranta, Aino-Maija; Venäläinen, Taisa; Soininen, Sonja; Jalkanen, Henna; Kiiskinen, Sanna; Schwab, Ursula; Lakka, Timo A; Lindi, Virpi

2016-01-01

Data on food sources of nutrients are needed to improve strategies to enhance nutrient intake among girls and boys in Western countries. To identify major food sources of energy, energy nutrients, dietary fibre, and micronutrients, and to study gender differences in these food sources among children. We assessed food consumption and nutrient intake using 4-day food records in a population sample of Finnish girls ( n =213) and boys ( n =217) aged 6-8 years from the Physical Activity and Nutrition in Children Study. We calculated the percentual contribution of 55 food groups for energy and nutrient intake using the population proportion method. Low-fibre grain products, skimmed milk, and high-fibre bread provided almost 23% of total energy intake. Skimmed milk was the top source of protein (18% of total intake), vitamin D (32%), potassium (20%), calcium (39%), magnesium (17%), and zinc (16%). Vegetable oils (15%) and high-fat vegetable oil-based spreads (14%) were the top sources of polyunsaturated fat. High-fibre bread was the top source of fibre (27%) and iron (12%). Non-root vegetables were the top source of folate (14%) and vitamin C (22%). Sugar-sweetened beverages provided 21% of sucrose intake. Pork was a more important source of protein and sausage was a more important source of total fat and monounsaturated fat in boys than in girls. Vegetable oils provided a higher proportion of unsaturated fat and vitamin E among boys, whereas high-fat vegetable oil-based spreads provided a higher proportion of these nutrients among girls. Commonly recommended foods, such as skimmed milk, high-fibre grain products, vegetables, vegetable oil, and vegetable oil-based spreads, were important sources of several nutrients, whereas sugar-sweetened beverages provided the majority of sucrose intake among children. This knowledge can be used in improving health among children by dietary interventions, nutrition education, and health policy decision making.

Food sources of energy and nutrients in Finnish girls and boys 6–8 years of age – the PANIC study

PubMed Central

Eloranta, Aino-Maija; Venäläinen, Taisa; Soininen, Sonja; Jalkanen, Henna; Kiiskinen, Sanna; Schwab, Ursula; Lakka, Timo A.; Lindi, Virpi

2016-01-01

Background Data on food sources of nutrients are needed to improve strategies to enhance nutrient intake among girls and boys in Western countries. Objective To identify major food sources of energy, energy nutrients, dietary fibre, and micronutrients, and to study gender differences in these food sources among children. Design We assessed food consumption and nutrient intake using 4-day food records in a population sample of Finnish girls (n=213) and boys (n=217) aged 6–8 years from the Physical Activity and Nutrition in Children Study. We calculated the percentual contribution of 55 food groups for energy and nutrient intake using the population proportion method. Results Low-fibre grain products, skimmed milk, and high-fibre bread provided almost 23% of total energy intake. Skimmed milk was the top source of protein (18% of total intake), vitamin D (32%), potassium (20%), calcium (39%), magnesium (17%), and zinc (16%). Vegetable oils (15%) and high-fat vegetable oil–based spreads (14%) were the top sources of polyunsaturated fat. High-fibre bread was the top source of fibre (27%) and iron (12%). Non-root vegetables were the top source of folate (14%) and vitamin C (22%). Sugar-sweetened beverages provided 21% of sucrose intake. Pork was a more important source of protein and sausage was a more important source of total fat and monounsaturated fat in boys than in girls. Vegetable oils provided a higher proportion of unsaturated fat and vitamin E among boys, whereas high-fat vegetable oil–based spreads provided a higher proportion of these nutrients among girls. Conclusion Commonly recommended foods, such as skimmed milk, high-fibre grain products, vegetables, vegetable oil, and vegetable oil–based spreads, were important sources of several nutrients, whereas sugar-sweetened beverages provided the majority of sucrose intake among children. This knowledge can be used in improving health among children by dietary interventions, nutrition education, and health policy decision making. PMID:27702428

Estimation of nutrient discharge from the Yangtze River to the East China Sea and the identification of nutrient sources.

PubMed

Tong, Yindong; Bu, Xiaoge; Chen, Junyue; Zhou, Feng; Chen, Long; Liu, Maodian; Tan, Xin; Yu, Tao; Zhang, Wei; Mi, Zhaorong; Ma, Lekuan; Wang, Xuejun; Ni, Jing

2017-01-05

Based on a time-series dataset and the mass balance method, the contributions of various sources to the nutrient discharges from the Yangtze River to the East China Sea are identified. The results indicate that the nutrient concentrations vary considerably among different sections of the Yangtze River. Non-point sources are an important source of nutrients to the Yangtze River, contributing about 36% and 63% of the nitrogen and phosphorus discharged into the East China Sea, respectively. Nutrient inputs from non-point sources vary among the sections of the Yangtze River, and the contributions of non-point sources increase from upstream to downstream. Considering the rice growing patterns in the Yangtze River Basin, the synchrony of rice tillering and the wet seasons might be an important cause of the high nutrient discharge from the non-point sources. Based on our calculations, a reduction of 0.99Tg per year in total nitrogen discharges from the Yangtze River would be needed to limit the occurrences of harmful algal blooms in the East China Sea to 15 times per year. The extensive construction of sewage treatment plants in urban areas may have only a limited effect on reducing the occurrences of harmful algal blooms in the future. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of the SPARROW model to assess surface-water nutrient conditions and sources in the United States Pacific Northwest

USGS Publications Warehouse

Wise, Daniel R.; Johnson, Henry M.

2013-01-01

The watershed model SPARROW (Spatially Referenced Regressions on Watershed attributes) was used to estimate mean annual surface-water nutrient conditions (total nitrogen and total phosphorus) and to identify important nutrient sources in catchments of the Pacific Northwest region of the United States for 2002. Model-estimated nutrient yields were generally higher in catchments on the wetter, western side of the Cascade Range than in catchments on the drier, eastern side. The largest source of locally generated total nitrogen stream load in most catchments was runoff from forestland, whereas the largest source of locally generated total phosphorus stream load in most catchments was either geologic material or livestock manure (primarily from grazing livestock). However, the highest total nitrogen and total phosphorus yields were predicted in the relatively small number of catchments where urban sources were the largest contributor to local stream load. Two examples are presented that show how SPARROW results can be applied to large rivers—the relative contribution of different nutrient sources to the total nitrogen load in the Willamette River and the total phosphorus load in the Snake River. The results from this study provided an understanding of the regional patterns in surface-water nutrient conditions and should be useful to researchers and water-quality managers performing local nutrient assessments.

CADDIS Volume 2. Sources, Stressors and Responses: Nutrients

EPA Pesticide Factsheets

Introduction to the nutrients module, when to list nutrients as a candidate cause, ways to measure nutrients, simple and detailed conceptual diagrams for nutrients, nutrients module references and literature reviews.

Hydrology and water quality of forested lands in eastern North Carolina

Treesearch

G.M. Chescheir; M.E. Lebo; D.M. Amatya; J. Hughes; J.W. Gilliam; R.W. Skaggs; R.B. Herrmann

2003-01-01

Nonpoint sources of nutrients (NPS) are a widespread source of surface water pollution throu&out the United States. Characterizing the sources of this NPS nutrient loading is challenging due to variation in land management practices, physioyaphic setting, site conditions such as soil type, and climatic variation. For nutrients, there is the added challenge of...

Nutrient load summaries for major lakes and estuaries of the Eastern United States, 2002

USGS Publications Warehouse

Moorman, Michelle C.; Hoos, Anne B.; Bricker, Suzanne B.; Moore, Richard B.; García, Ana María; Ator, Scott W.

2014-01-01

Nutrient enrichment of lakes and estuaries across the Nation is widespread. Nutrient enrichment can stimulate excessive plant and algal growth and cause a number of undesirable effects that impair aquatic life and recreational activities and can also result in economic effects. Understanding the amount of nutrients entering lakes and estuaries, the physical characteristics affecting the nutrient processing within these receiving waterbodies, and the natural and manmade sources of nutrients is fundamental to the development of effective nutrient reduction strategies. To improve this understanding, sources and stream transport of nutrients to 255 major lakes and 64 estuaries in the Eastern United States were estimated using Spatially Referenced Regression on Watershed attributes (SPARROW) nutrient models.

Increased fluxes of shelf-derived materials to the central Arctic Ocean

PubMed Central

Kipp, Lauren E.; Charette, Matthew A.; Moore, Willard S.; Henderson, Paul B.; Rigor, Ignatius G.

2018-01-01

Rising temperatures in the Arctic Ocean region are responsible for changes such as reduced ice cover, permafrost thawing, and increased river discharge, which, together, alter nutrient and carbon cycles over the vast Arctic continental shelf. We show that the concentration of radium-228, sourced to seawater through sediment-water exchange processes, has increased substantially in surface waters of the central Arctic Ocean over the past decade. A mass balance model for 228Ra suggests that this increase is due to an intensification of shelf-derived material inputs to the central basin, a source that would also carry elevated concentrations of dissolved organic carbon and nutrients. Therefore, we suggest that significant changes in the nutrient, carbon, and trace metal balances of the Arctic Ocean are underway, with the potential to affect biological productivity and species assemblages in Arctic surface waters. PMID:29326980

Nutrient patterns and their food sources in an International Study Setting: report from the EPIC study.

PubMed

Moskal, Aurelie; Pisa, Pedro T; Ferrari, Pietro; Byrnes, Graham; Freisling, Heinz; Boutron-Ruault, Marie-Christine; Cadeau, Claire; Nailler, Laura; Wendt, Andrea; Kühn, Tilman; Boeing, Heiner; Buijsse, Brian; Tjønneland, Anne; Halkjær, Jytte; Dahm, Christina C; Chiuve, Stephanie E; Quirós, Jose R; Buckland, Genevieve; Molina-Montes, Esther; Amiano, Pilar; Huerta Castaño, José M; Gurrea, Aurelio Barricarte; Khaw, Kay-Tee; Lentjes, Marleen A; Key, Timothy J; Romaguera, Dora; Vergnaud, Anne-Claire; Trichopoulou, Antonia; Bamia, Christina; Orfanos, Philippos; Palli, Domenico; Pala, Valeria; Tumino, Rosario; Sacerdote, Carlotta; de Magistris, Maria Santucci; Bueno-de-Mesquita, H Bas; Ocké, Marga C; Beulens, Joline W J; Ericson, Ulrika; Drake, Isabel; Nilsson, Lena M; Winkvist, Anna; Weiderpass, Elisabete; Hjartåker, Anette; Riboli, Elio; Slimani, Nadia

2014-01-01

Compared to food patterns, nutrient patterns have been rarely used particularly at international level. We studied, in the context of a multi-center study with heterogeneous data, the methodological challenges regarding pattern analyses. We identified nutrient patterns from food frequency questionnaires (FFQ) in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study and used 24-hour dietary recall (24-HDR) data to validate and describe the nutrient patterns and their related food sources. Associations between lifestyle factors and the nutrient patterns were also examined. Principal component analysis (PCA) was applied on 23 nutrients derived from country-specific FFQ combining data from all EPIC centers (N = 477,312). Harmonized 24-HDRs available for a representative sample of the EPIC populations (N = 34,436) provided accurate mean group estimates of nutrients and foods by quintiles of pattern scores, presented graphically. An overall PCA combining all data captured a good proportion of the variance explained in each EPIC center. Four nutrient patterns were identified explaining 67% of the total variance: Principle component (PC) 1 was characterized by a high contribution of nutrients from plant food sources and a low contribution of nutrients from animal food sources; PC2 by a high contribution of micro-nutrients and proteins; PC3 was characterized by polyunsaturated fatty acids and vitamin D; PC4 was characterized by calcium, proteins, riboflavin, and phosphorus. The nutrients with high loadings on a particular pattern as derived from country-specific FFQ also showed high deviations in their mean EPIC intakes by quintiles of pattern scores when estimated from 24-HDR. Center and energy intake explained most of the variability in pattern scores. The use of 24-HDR enabled internal validation and facilitated the interpretation of the nutrient patterns derived from FFQs in term of food sources. These outcomes open research opportunities and perspectives of using nutrient patterns in future studies particularly at international level.

Food sources of energy and nutrients among adults in the US: NHANES 2003–2006.

PubMed

O'Neil, Carol E; Keast, Debra R; Fulgoni, Victor L; Nicklas, Theresa A

2012-12-19

Identification of current food sources of energy and nutrients among US adults is needed to help with public health efforts to implement feasible and appropriate dietary recommendations. To determine the food sources of energy and 26 nutrients consumed by US adults the 2003-2006 National Health and Nutrition Examination Survey (NHANES) 24-h recall (Day 1) dietary intake data from a nationally representative sample of adults 19+ years of age (y) (n = 9490) were analyzed. An updated USDA Dietary Source Nutrient Database was developed for NHANES 2003-2006 using current food composition databases. Food grouping included ingredients from disaggregated mixtures. Mean energy and nutrient intakes from food sources were sample-weighted. Percentages of total dietary intake contributed from food sources were ranked. The highest ranked sources of energy and nutrients among adults more than 19 years old were: energy - yeast bread/rolls (7.2%) and cake/cookies/quick bread/pastry/pie (7.2%); protein-poultry (14.4%) and beef (14.0%); total fat - other fats and oils (9.8%); saturated fatty acids - cheese (16.5%) and beef (9.1%); carbohydrate - soft drinks/soda (11.4%) and yeast breads/rolls (10.9%); dietary fiber - yeast breads/rolls (10.9%) and fruit (10.2%); calcium - milk (22.5%) and cheese (21.6%); vitamin D - milk (45.1%) and fish/shellfish (14.4%); and potassium - milk (9.6%) and coffee/tea/other non-alcoholic beverages (8.4%). Knowledge of primary food sources of energy and nutrients can help health professionals design effective strategies to reduce excess energy consumed by US adults and increase the nutrient adequacy of their diets.

Food Sources of Energy and Nutrients among Adults in the US: NHANES 2003–2006

PubMed Central

O’Neil, Carol E.; Keast, Debra R.; Fulgoni, Victor L.; Nicklas, Theresa A.

2012-01-01

Identification of current food sources of energy and nutrients among US adults is needed to help with public health efforts to implement feasible and appropriate dietary recommendations. To determine the food sources of energy and 26 nutrients consumed by US adults the 2003–2006 National Health and Nutrition Examination Survey (NHANES) 24-h recall (Day 1) dietary intake data from a nationally representative sample of adults 19+ years of age (y) (n = 9490) were analyzed. An updated USDA Dietary Source Nutrient Database was developed for NHANES 2003–2006 using current food composition databases. Food grouping included ingredients from disaggregated mixtures. Mean energy and nutrient intakes from food sources were sample-weighted. Percentages of total dietary intake contributed from food sources were ranked. The highest ranked sources of energy and nutrients among adults more than 19 years old were: energy—yeast bread/rolls (7.2%) and cake/cookies/quick bread/pastry/pie (7.2%); protein—poultry (14.4%) and beef (14.0%); total fat—other fats and oils (9.8%); saturated fatty acids—cheese (16.5%) and beef (9.1%); carbohydrate—soft drinks/soda (11.4%) and yeast breads/rolls (10.9%); dietary fiber—yeast breads/rolls (10.9%) and fruit (10.2%); calcium—milk (22.5%) and cheese (21.6%); vitamin D—milk (45.1%) and fish/shellfish (14.4%); and potassium—milk (9.6%) and coffee/tea/other non-alcoholic beverages (8.4%). Knowledge of primary food sources of energy and nutrients can help health professionals design effective strategies to reduce excess energy consumed by US adults and increase the nutrient adequacy of their diets. PMID:23363999

Stakeholder co-development of farm level nutrient management software

NASA Astrophysics Data System (ADS)

Buckley, Cathal; Mechan, Sarah; Macken-Walsh, Aine; Heanue, Kevin

2013-04-01

Over the last number of decades intensification in the use nitrogen (N) and phosphorus (P) in agricultural production has lead to excessive accumulations of these nutrients in soils, groundwaters and surface water bodies (Sutton et al., 2011). According to the European Environment Agency (2012) despite some progress diffuse pollution from agriculture is still significant in more than 40% of Europe's water bodies in rivers and coastal waters, and in one third of the water bodies in lakes and transitional waters. Recently it was estimated that approximately 29% of monitored river channel length is polluted to some degree across the Republic of Ireland. Agricultural sources were suspected in 47 per cent of cases (EPA, 2012). Farm level management practices to reduce nutrient transfers from agricultural land to watercourses can be divided into source reduction and source interception approaches (Ribaudo et al., 2001). Source interception approaches involve capturing nutrients post mobilisation through policy instruments such as riparian buffer zones or wetlands. Conversely, the source reduction approach is preventative in nature and promotes strict management of nutrient at farm and field level to reduce risk of mobilisation in the first instance. This has the potential to deliver a double dividend of reduced nutrient loss to the wider ecosystem while maximising economic return to agricultural production at the field and farm levels. Adoption and use of nutrient management plans among farmers is far from the norm. This research engages key farmer and extension stakeholders to explore how current nutrient management planning software and outputs should be developed to make it more user friendly and usable in a practical way. An open innovation technology co-development approach was adopted to investigate what is demanded by the end users - farm advisors and farmers. Open innovation is a knowledge management strategy that uses the input of stakeholders to improve internal innovation processes. Open innovation incorporates processes such as 'user-led' (farmer and advisor) innovation and the 'co-development' (by technologists and users) of a technology. This strategy is increasingly used by a variety of organisations across sectors to try to ensure that the use of their outputs (products/services/technologies) is optimised by their target customers/clients, by incorporating user insights into the development of outputs. This research use the open innovation co-development framework through farmer and farm advisor focus group sessions to inform the development of a desirable software package for nutrient management planners (farm advisors) and desirable output formats for the end user (farmers). References Sutton, M., Oenema, O., Erisman, J. W., Leip, A., Grinsven, H. & Winiwarter, W. 2011. Too much of a good thing. Nature, 472, 159.161. European Environment Agency, 2012. European waters — assessment of status and pressures. Environmental Protection Agency, 2012. Ireland's Environment: An assessment 2012. Ribaudo, M.O., Heimlich, R., Claassen, R., Peters, M., 2001. Least-cost management of nonpoint source pollution: source reduction versus interception strategies for controlling nitrogen loss in the Mississippi Basin. Ecological Economics, 37, 183-197.

CADDIS Volume 2. Sources, Stressors and Responses: Nutrients - Simple Conceptual Diagram

EPA Pesticide Factsheets

Introduction to the nutrients module, when to list nutrients as a candidate cause, ways to measure nutrients, simple and detailed conceptual diagrams for nutrients, nutrients module references and literature reviews.

A 3D parameterization of iron atmospheric deposition to the global ocean

NASA Astrophysics Data System (ADS)

Myriokefalitakis, Stelios; Krol, Maarten C.; van Noije, Twan P. C.; Le Sager, Philippe

2017-04-01

Atmospheric deposition of trace constituents, both of natural and anthropogenic origin, can act as a nutrient source into the open ocean and affect marine ecosystem functioning and subsequently the exchange of CO2 between the atmosphere and the global ocean. Dust is known as a major source of nutrients to the global ocean, but only a fraction of these nutrients is released in soluble form that can be assimilated by the ecosystems. Iron (Fe) is a key micronutrient that significantly modulates gross primary production in High-Nutrient-Low-Chlorophyll (HNLC) oceans, where macronutrients like nitrate are abundant but primary production is limited by Fe scarcity. The global atmospheric Fe cycle is here parameterized in the state-of-the-art global Earth System Model EC-Earth. The model takes into account the primary emissions of both insoluble and soluble Fe, associated with dusts and combustion processes. The impact of atmospheric acidity on mineral solubility is parameterized based on updated experimental and theoretical findings, and model results are evaluated against available observations. The link between the soluble Fe atmospheric deposition and anthropogenic sources is also investigated. Overall, the response of the chemical composition of nutrient containing aerosols to atmospheric composition changes is demonstrated and quantified. This work has been financed by the Marie-Curie H2020-MSCA-IF-2015 grant (ID 705652) ODEON (Online DEposition over OceaNs: Modeling the effect of air pollution on ocean bio-geochemistry in an Earth System Model).

Deoiledjatropha seed cake is a useful nutrient for pullulan production.

PubMed

Choudhury, Anirban Roy; Sharma, Nishat; Prasad, G S

2012-03-30

Ever increasing demand for fossil fuels is a major factor for rapid depletion of these non-renewable energy resources, which has enhanced the interest of finding out alternative sources of energy. In recent years jatropha seed oil has been used extensively for production of bio-diesel and has shown significant potential to replace petroleum fuels at least partially. De-oiled jatropha seed cake (DOJSC) which comprises of approximately 55 to 65% of the biomass is a byproduct of bio-diesel industry. DOJSC contains toxic components like phorbol esters which restricts its utilization as animal feed. Thus along with the enhancement of biodiesel production from jatropha, there is an associated problem of handling this toxic byproduct. Utilization of DOJSC as a feed stock for production of biochemicals may be an attractive solution to the problem.Pullulan is an industrially important polysaccharide with several potential applications in food, pharmaceuticals and cosmetic industries. However, the major bottleneck for commercial utilization of pullulan is its high cost. A cost effective process for pullulan production may be developed using DOJSC as sole nutrient source which will in turn also help in utilization of the byproduct of bio-diesel industry. In the present study, DOJSC has been used as a nutrient for production of pullulan, in place of conventional nutrients like yeast extract and peptone. Process optimization was done in shake flasks, and under optimized conditions (8% DOJSC, 15% dextrose, 28°C temperature, 200 rpm, 5% inoculum, 6.0 pH) 83.98 g/L pullulan was obtained. The process was further validated in a 5 L laboratory scale fermenter. This is the first report of using DOJSC as nutrient for production of an exopolysaccharide. Successful use of DOJSC as nutrient will help in finding significant application of this toxic byproduct of biodiesel industry. This in turn also have a significant impact on cost reduction and may lead to development of a cost effective green technology for pullulan production.

Deoiledjatropha seed cake is a useful nutrient for pullulan production

PubMed Central

2012-01-01

Background Ever increasing demand for fossil fuels is a major factor for rapid depletion of these non-renewable energy resources, which has enhanced the interest of finding out alternative sources of energy. In recent years jatropha seed oil has been used extensively for production of bio-diesel and has shown significant potential to replace petroleum fuels at least partially. De-oiled jatropha seed cake (DOJSC) which comprises of approximately 55 to 65% of the biomass is a byproduct of bio-diesel industry. DOJSC contains toxic components like phorbol esters which restricts its utilization as animal feed. Thus along with the enhancement of biodiesel production from jatropha, there is an associated problem of handling this toxic byproduct. Utilization of DOJSC as a feed stock for production of biochemicals may be an attractive solution to the problem. Pullulan is an industrially important polysaccharide with several potential applications in food, pharmaceuticals and cosmetic industries. However, the major bottleneck for commercial utilization of pullulan is its high cost. A cost effective process for pullulan production may be developed using DOJSC as sole nutrient source which will in turn also help in utilization of the byproduct of bio-diesel industry. Results In the present study, DOJSC has been used as a nutrient for production of pullulan, in place of conventional nutrients like yeast extract and peptone. Process optimization was done in shake flasks, and under optimized conditions (8% DOJSC, 15% dextrose, 28°C temperature, 200 rpm, 5% inoculum, 6.0 pH) 83.98 g/L pullulan was obtained. The process was further validated in a 5 L laboratory scale fermenter. Conclusion This is the first report of using DOJSC as nutrient for production of an exopolysaccharide. Successful use of DOJSC as nutrient will help in finding significant application of this toxic byproduct of biodiesel industry. This in turn also have a significant impact on cost reduction and may lead to development of a cost effective green technology for pullulan production. PMID:22462652

Reduced nutrient pollution in a rural stream following septic tank upgrade and installation of runoff retention measures.

PubMed

Ockenden, M C; Quinton, J N; Favaretto, N; Deasy, C; Surridge, B

2014-07-01

Surface water quality in the UK and much of Western Europe has improved in recent decades, in response to better point source controls and the regulation of fertilizer, manure and slurry use. However, diffuse sources of pollution, such as leaching or runoff of nutrients from agricultural fields, and micro-point sources including farmyards, manure heaps and septic tank sewerage systems, particularly systems without soil adsorption beds, are now hypothesised to contribute a significant proportion of the nutrients delivered to surface watercourses. Tackling such sources in an integrated manner is vital, if improvements in freshwater quality are to continue. In this research, we consider the combined effect of constructing small field wetlands and improving a septic tank system on stream water quality within an agricultural catchment in Cumbria, UK. Water quality in the ditch-wetland system was monitored by manual sampling at fortnightly intervals (April-October 2011 and February-October 2012), with the septic tank improvement taking place in February 2012. Reductions in nutrient concentrations were observed through the catchment, by up to 60% when considering total phosphorus (TP) entering and leaving a wetland with a long residence time. Average fluxes of TP, soluble reactive phosphorus (SRP) and ammonium-N (NH4-N) at the head of the ditch system in 2011 (before septic tank improvement) compared to 2012 (after septic tank improvement) were reduced by 28%, 9% and 37% respectively. However, TP concentration data continue to show a clear dilution with increasing flow, indicating that the system remained point source dominated even after the septic tank improvement.

Impact of Climate Variability and Landscape Patterns on Water Budget and Nutrient Loads in a Peri-urban Watershed: A Coupled Analysis Using Process-based Hydrological Model and Landscape Indices.

PubMed

Li, Chongwei; Zhang, Yajuan; Kharel, Gehendra; Zou, Chris B

2018-06-01

Nutrient discharge into peri-urban streams and reservoirs constitutes a significant pressure on environmental management, but quantitative assessment of non-point source pollution under climate variability in fast changing peri-urban watersheds is challenging. Soil and Water Assessment Tool (SWAT) was used to simulate water budget and nutrient loads for landscape patterns representing a 30-year progression of urbanization in a peri-urban watershed near Tianjin metropolis, China. A suite of landscape pattern indices was related to nitrogen (N) and phosphorous (P) loads under dry and wet climate using CANOCO redundancy analysis. The calibrated SWAT model was adequate to simulate runoff and nutrient loads for this peri-urban watershed, with Nash-Sutcliffe coefficient (NSE) and coefficient of determination (R 2 ) > 0.70 and percentage bias (PBIAS) between -7 and +18 for calibration and validation periods. With the progression of urbanization, forest remained the main "sink" landscape while cultivated and urban lands remained the main "source" landscapes with the role of orchard and grassland being uncertain and changing with time. Compared to 1984, the landscape use pattern in 2013 increased nutrient discharge by 10%. Nutrient loads modelled under wet climate were 3-4 times higher than that under dry climate for the same landscape pattern. Results indicate that climate change could impose a far greater impact on runoff and nutrient discharge in a peri-urban watershed than landscape pattern change.

Impact of Climate Variability and Landscape Patterns on Water Budget and Nutrient Loads in a Peri-urban Watershed: A Coupled Analysis Using Process-based Hydrological Model and Landscape Indices

NASA Astrophysics Data System (ADS)

Li, Chongwei; Zhang, Yajuan; Kharel, Gehendra; Zou, Chris B.

2018-06-01

Nutrient discharge into peri-urban streams and reservoirs constitutes a significant pressure on environmental management, but quantitative assessment of non-point source pollution under climate variability in fast changing peri-urban watersheds is challenging. Soil and Water Assessment Tool (SWAT) was used to simulate water budget and nutrient loads for landscape patterns representing a 30-year progression of urbanization in a peri-urban watershed near Tianjin metropolis, China. A suite of landscape pattern indices was related to nitrogen (N) and phosphorous (P) loads under dry and wet climate using CANOCO redundancy analysis. The calibrated SWAT model was adequate to simulate runoff and nutrient loads for this peri-urban watershed, with Nash-Sutcliffe coefficient (NSE) and coefficient of determination ( R 2) > 0.70 and percentage bias (PBIAS) between -7 and +18 for calibration and validation periods. With the progression of urbanization, forest remained the main "sink" landscape while cultivated and urban lands remained the main "source" landscapes with the role of orchard and grassland being uncertain and changing with time. Compared to 1984, the landscape use pattern in 2013 increased nutrient discharge by 10%. Nutrient loads modelled under wet climate were 3-4 times higher than that under dry climate for the same landscape pattern. Results indicate that climate change could impose a far greater impact on runoff and nutrient discharge in a peri-urban watershed than landscape pattern change.

Evidence of chronic anthropogenic nutrient within coastal lagoon reefs adjacent to urban and tourism centers, Kenya: A stable isotope approach.

PubMed

Mwaura, Jelvas; Umezawa, Yu; Nakamura, Takashi; Kamau, Joseph

2017-06-30

The source of anthropogenic nutrient and its spatial extent in three fringing reefs with differing human population gradients in Kenya were investigated using stable isotope approaches. Nutrient concentrations and nitrate-δ 15 N in seepage water indicated that population density and tourism contributed greatly to the extent of nutrient loading to adjacent reefs. Although water-column nutrient analyses did not show any significant difference among the reefs, higher δ 15 N and N contents in macrophytes showed terrestrial nutrients affected primary producers in onshore areas in Nyali and Bamburi reefs, but were mitigated by offshore water intrusion especially at Nyali. On the offshore reef flat, where the same species of macroalgae were not available, complementary use of δ 15 N in sedimentary organic matter suggested inputs of nutrients originated from the urban city of Mombasa. If population increases in the future, nutrient conditions in the shallower reef, Vipingo, may be dramatically degraded due to lower water exchange ratio. Copyright © 2017 Elsevier Ltd. All rights reserved.

Using Soluble Reactive Phosphorus and Ammonia to Identify Point Source Discharge from Large Livestock Facilities

NASA Astrophysics Data System (ADS)

Borrello, M. C.; Scribner, M.; Chessin, K.

2013-12-01

A growing body of research draws attention to the negative environmental impacts on surface water from large livestock facilities. These impacts are mostly in the form of excessive nutrient loading resulting in significantly decreased oxygen levels. Over-application of animal waste on fields as well as direct discharge into surface water from facilities themselves has been identified as the main contributor to the development of hypoxic zones in Lake Erie, Chesapeake Bay and the Gulf of Mexico. Some regulators claim enforcement of water quality laws is problematic because of the nature and pervasiveness of non-point source impacts. Any direct discharge by a facility is a violation of permits governed by the Clean Water Act, unless the facility has special dispensation for discharge. Previous research by the principal author and others has shown runoff and underdrain transport are the main mechanisms by which nutrients enter surface water. This study utilized previous work to determine if the effects of non-point source discharge can be distinguished from direct (point-source) discharge using simple nutrient analysis and dissolved oxygen (DO) parameters. Nutrient and DO parameters were measured from three sites: 1. A stream adjacent to a field receiving manure, upstream of a large livestock facility with a history of direct discharge, 2. The same stream downstream of the facility and 3. A stream in an area relatively unimpacted by large-scale agriculture (control site). Results show that calculating a simple Pearson correlation coefficient (r) of soluble reactive phosphorus (SRP) and ammonia over time as well as temperature and DO, distinguishes non-point source from point source discharge into surface water. The r value for SRP and ammonia for the upstream site was 0.01 while the r value for the downstream site was 0.92. The control site had an r value of 0.20. Likewise, r values were calculated on temperature and DO for each site. High negative correlations between temperature and DO are indicative of a relatively unimpacted stream. Results from this study are commensurate with nutrient correlations and are: r = -0.97 for the upstream site, r = -0.21 for the downstream site and r = -0.89 for the control site. Results from every site tested were statistically significant (p ≤ 0.05). These results support previous studies and demonstrate that the simple analytical techniques mentioned provide an effective means for regulatory agencies and community groups to monitor and identify point source discharge from large livestock facilities.

Defense Coastal/Estuarine Research Program (DCERP) Strategic Plan

DTIC Science & Technology

2007-09-01

atmospheric deposition. The source apportionment of nutrients from atmospheric deposition (especially nitrogen) to estuarine waters derived from direct...migrating wildlife, and nutrient release from soil weathering, atmospheric deposition represents the only source of new nutrients into the... apportionment to properly assess the contributions of off-site and on-site emission sources to regional levels of PM2.5. In preparing this DCERP Strategic

CADDIS Volume 2. Sources, Stressors and Responses: Nutrients - Detailed Conceptual Diagram (N)

EPA Pesticide Factsheets

Introduction to the nutrients module, when to list nutrients as a candidate cause, ways to measure nutrients, simple and detailed conceptual diagrams for nutrients, nutrients module references and literature reviews.

CADDIS Volume 2. Sources, Stressors and Responses: Nutrients - Detailed Conceptual Diagram (P)

EPA Pesticide Factsheets

Introduction to the nutrients module, when to list nutrients as a candidate cause, ways to measure nutrients, simple and detailed conceptual diagrams for nutrients, nutrients module references and literature reviews.

Antioxidant Activities, Metabolic Profiling, Proximate Analysis, Mineral Nutrient Composition of Salvadora persica Fruit Unravel a Potential Functional Food and a Natural Source of Pharmaceuticals.

PubMed

Kumari, Asha; Parida, Asish K; Rangani, Jaykumar; Panda, Ashok

2017-01-01

Salvadora persica is a medicinally important plant mainly used in oral hygiene. However, little attention has been given towards the nutritional prominence of this plant. This study encloses the proximate and mineral nutrient contents, amino acid composition, metabolite profiling and antioxidant potential of S. persica fruit. The ripen fruit contained substantial amount of sugars, mineral nutrients, carotenoids, polyphenols and flavonoids. The metabolic profiling of the fruit extract by GC-MS revealed a total of 22 metabolites comprising of sugars, sugar alcohols, organic acids, organic base, and aromatic silica compound. The identified metabolites have been previously reported to have potential antioxidant, antimicrobial, anti-hyperglycemic, and antitumor properties. The GC-MS analysis indicated high glucose and glucopyranose (247.62 and 42.90 mg g -1 FW respectively) contents in fruit of S. persica . The fruit extract demonstrated a significantly higher antioxidant and ROS scavenging properties along with high contents of mineral nutrients and essential amino acids. HPLC analysis revealed presence of essential and non-essential amino acid required for healthy body metabolism. The cysteine was found to be in highest amount (733.69 mg 100 g -1 DW) among all amino acids quantified. Specifically, compared to similar medicinal plants, previously reported as a source of non-conventional food and with some of the commercially important fruits, S. persica fruit appears to be a potential source of essential mineral nutrients, amino acids, vitamins (ascorbic acid and carotenoid) and pharmaceutically important metabolites contributing towards fulfilling the recommended daily requirement of these for a healthy human being. This is the first report establishing importance of S. persica fruit as nutraceuticals. The data presented here proposed that fruit of S. persica may be used as functional food or reinvigorating ingredient for processed food to reduce deficiency of nutrients among the vulnerable population group. The phytochemicals identified from S. persica fruit may be used as natural source for pharmaceutical preparations.

Antioxidant Activities, Metabolic Profiling, Proximate Analysis, Mineral Nutrient Composition of Salvadora persica Fruit Unravel a Potential Functional Food and a Natural Source of Pharmaceuticals

PubMed Central

Kumari, Asha; Parida, Asish K.; Rangani, Jaykumar; Panda, Ashok

2017-01-01

Salvadora persica is a medicinally important plant mainly used in oral hygiene. However, little attention has been given towards the nutritional prominence of this plant. This study encloses the proximate and mineral nutrient contents, amino acid composition, metabolite profiling and antioxidant potential of S. persica fruit. The ripen fruit contained substantial amount of sugars, mineral nutrients, carotenoids, polyphenols and flavonoids. The metabolic profiling of the fruit extract by GC-MS revealed a total of 22 metabolites comprising of sugars, sugar alcohols, organic acids, organic base, and aromatic silica compound. The identified metabolites have been previously reported to have potential antioxidant, antimicrobial, anti-hyperglycemic, and antitumor properties. The GC-MS analysis indicated high glucose and glucopyranose (247.62 and 42.90 mg g-1 FW respectively) contents in fruit of S. persica. The fruit extract demonstrated a significantly higher antioxidant and ROS scavenging properties along with high contents of mineral nutrients and essential amino acids. HPLC analysis revealed presence of essential and non-essential amino acid required for healthy body metabolism. The cysteine was found to be in highest amount (733.69 mg 100 g-1 DW) among all amino acids quantified. Specifically, compared to similar medicinal plants, previously reported as a source of non-conventional food and with some of the commercially important fruits, S. persica fruit appears to be a potential source of essential mineral nutrients, amino acids, vitamins (ascorbic acid and carotenoid) and pharmaceutically important metabolites contributing towards fulfilling the recommended daily requirement of these for a healthy human being. This is the first report establishing importance of S. persica fruit as nutraceuticals. The data presented here proposed that fruit of S. persica may be used as functional food or reinvigorating ingredient for processed food to reduce deficiency of nutrients among the vulnerable population group. The phytochemicals identified from S. persica fruit may be used as natural source for pharmaceutical preparations. PMID:28261096

Nutrient Sourcing of Ten Plant Species in the Southwest U.S. using Strontium Isotopes: Effects of Rooting Depth, Bedrock Type, and Landscape Age

NASA Astrophysics Data System (ADS)

Reynolds, A. C.; Quade, J.; Betancourt, J. L.

2007-12-01

For decades, researchers have been examining chronosequences in Hawaii to quantify mineral weathering rates and tropical plant nutrient pools. Within El Malpais National Park, New Mexico, well-dated basalt flows allow for comparison of the Hawaiian data to a semi-arid ecosystem. We measured 87Sr/86Sr ratios in cellulose and bedrock to gauge tree, shrub, & grass (Pinus ponderosa, Pinus edulis, Juniperus monosperma, Juniperus scopulorum, Populus tremuloides, Chrysothamus nauseosus, Fallugia paradoxa, Rhus trilobata, Bouteloua gracilis, and Xanthoparmelia lineola (Berry) Hale) dependence on atmospheric dust as a nutrient source. Sampling sites varied by bedrock type (limestone, sandstone, granite, cinder and basalt) and by age (Quaternary to Precambrian) providing a wide and discrete range of 87Sr/86Sr ratios. Thus, we can pinpoint the roles landscape age (3 ka to greater than 200 ka) and bedrock recalcitrance play in mineral weathering versus eolian dust influence. This study suggests that dust dominates the nutrient cycle on younger landscapes (3 ka), shows a mixture of mineral weathering-dust inputs by 9 ka, and is rock-dominated by 120 ka. Rates of soil nutrient depletion vary in older, non-basalt landscapes (>250 ka), depending on the type the parent bedrock. For example, landscapes on Precambrian gneiss and Paleozoic limestone still show significant mineral contributions while the quartz-rich, carbonate-cemented Zuni Sandstone is almost completely eolian-dominated. Cellulose 87Sr/86Sr variation by plant species at a single site allows us to monitor plant rooting depths and interspecies competition for vital nutrients. Within semiarid ecosystems, nutrient concentrations exhibit both vertical and lateral heterogeneity. The reasons for this variation include vertical and lateral heterogeneity in soil moisture and foliar trapping of nutrient-rich dust followed by incorporation of the throughfall into the underlying soil. This study shows that throughfall does play a significant role for certain species (e.g. J. monosperma) but not for others. A species' ability to trap dust and its overall rooting depths both influence its nutrient intake.

Strontium source and depth of uptake shifts with substrate age in semiarid ecosystems

NASA Astrophysics Data System (ADS)

Coble, Ashley A.; Hart, Stephen C.; Ketterer, Michael E.; Newman, Gregory S.; Kowler, Andrew L.

2015-06-01

Without exogenous rock-derived nutrient sources, terrestrial ecosystems may eventually regress or reach a terminal steady state, but the degree to which exogenous nutrient sources buffer or slow to a theoretical terminal steady state remains unclear. We used strontium isotope ratios (87Sr/86Sr) as a tracer and measured 87Sr/86Sr values in aeolian dust, soils, and vegetation across a well-constrained 3 Myr semiarid substrate age gradient to determine (1) whether the contribution of atmospheric sources of rock-derived nutrients to soil and vegetation pools varied with substrate age and (2) to determine if the depth of uptake varied with substrate age. We found that aeolian-derived nutrients became increasingly important, contributing as much as 71% to plant-available soil pools and tree (Pinus edulis) growth during the latter stages of ecosystem development in a semiarid climate. The depth of nutrient uptake increased on older substrates, demonstrating that trees in arid regions can acquire nutrients from greater depths as ecosystem development progresses presumably in response to nutrient depletion in the more weathered surface soils. Our results demonstrate that global and regional aeolian transport of nutrients to local ecosystems is a vital process for ecosystem development in arid regions. Furthermore, these aeolian nutrient inputs contribute to deep soil nutrient pools, which become increasingly important for maintaining plant productivity over long time scales.

Food sources of energy and nutrients among children in the United States: National Health and Nutrition Examination Survey 2003–2006.

PubMed

Keast, Debra R; Fulgoni, Victor L; Nicklas, Theresa A; O'Neil, Carol E

2013-01-22

Recent detailed analyses of data on dietary sources of energy and nutrients in US children are lacking. The objective of this study was to identify food sources of energy and 28 nutrients for children in the United States. Analyses of food sources were conducted using a single 24-h recall collected from children 2 to 18 years old (n = 7332) in the 2003-2006 National Health and Nutrition Examination Survey. Sources of nutrients contained in foods were determined using nutrient composition databases. Food grouping included ingredients from disaggregated mixtures. Mean energy and nutrient intakes from the total diet and from each food group were adjusted for the sample design using appropriate weights. Percentages of the total dietary intake that food sources contributed were tabulated by rank order. The two top ranked food/food group sources of energy and nutrients were: energy - milk (7% of energy) and cake/cookies/quick bread/pastry/pie (7%); protein - milk (13.2%) and poultry (12.8%); total carbohydrate - soft drinks/soda (10.5%) and yeast bread/rolls (9.1%); total sugars - soft drinks/soda (19.2%) and yeast breads and rolls (12.7%); added sugars - soft drinks/soda (29.7%) and candy/sugar/sugary foods (18.6%); dietary fiber - fruit (10.4%) and yeast bread/rolls (10.3%); total fat - cheese (9.3%) and crackers/popcorn/pretzels/chips (8.4%); saturated fatty acids - cheese (16.3%) and milk (13.3%); cholesterol - eggs (24.2%) and poultry (13.2%); vitamin D - milk (60.4%) and milk drinks (8.3%); calcium - milk (33.2%) and cheese (19.4%); potassium - milk (18.8%) and fruit juice (8.0%); and sodium - salt (18.5%) and yeast bread and rolls (8.4%). Results suggest that many foods/food groupings consumed by children were energy dense, nutrient poor. Awareness of dietary sources of energy and nutrients can help health professionals design effective strategies to reduce energy consumption and increase the nutrient density of children's diets.

Food Sources of Energy and Nutrients among Children in the United States: National Health and Nutrition Examination Survey 2003–2006

PubMed Central

Keast, Debra R.; Fulgoni III, Victor L.; Nicklas, Theresa A.; O’Neil, Carol E.

2013-01-01

Background: Recent detailed analyses of data on dietary sources of energy and nutrients in US children are lacking. The objective of this study was to identify food sources of energy and 28 nutrients for children in the United States. Methods: Analyses of food sources were conducted using a single 24-h recall collected from children 2 to 18 years old (n = 7332) in the 2003–2006 National Health and Nutrition Examination Survey. Sources of nutrients contained in foods were determined using nutrient composition databases. Food grouping included ingredients from disaggregated mixtures. Mean energy and nutrient intakes from the total diet and from each food group were adjusted for the sample design using appropriate weights. Percentages of the total dietary intake that food sources contributed were tabulated by rank order. Results: The two top ranked food/food group sources of energy and nutrients were: energy—milk (7% of energy) and cake/cookies/quick bread/pastry/pie (7%); protein—milk (13.2%) and poultry (12.8%); total carbohydrate—soft drinks/soda (10.5%) and yeast bread/rolls (9.1%); total sugars—soft drinks/soda (19.2%) and yeast breads and rolls (12.7%); added sugars—soft drinks/soda (29.7%) and candy/sugar/sugary foods (18.6%); dietary fiber—fruit (10.4%) and yeast bread/rolls (10.3%); total fat—cheese (9.3%) and crackers/popcorn/pretzels/chips (8.4%); saturated fatty acids—cheese (16.3%) and milk (13.3%); cholesterol—eggs (24.2%) and poultry (13.2%); vitamin D—milk (60.4%) and milk drinks (8.3%); calcium—milk (33.2%) and cheese (19.4%); potassium—milk (18.8%) and fruit juice (8.0%); and sodium—salt (18.5%) and yeast bread and rolls (8.4%). Conclusions: Results suggest that many foods/food groupings consumed by children were energy dense, nutrient poor. Awareness of dietary sources of energy and nutrients can help health professionals design effective strategies to reduce energy consumption and increase the nutrient density of children’s diets. PMID:23340318

County-level estimates of nutrient inputs to the landsurface of the conterminous United States, 1982-2001

USGS Publications Warehouse

Ruddy, Barbara C.; Lorenz, David L.; Mueller, David K.

2006-01-01

Nutrient input data for fertilizer use, livestock manure, and atmospheric deposition from various sources were estimated and allocated to counties in the conterminous United States for the years 1982 through 2001. These nationally consistent nutrient input data are needed by the National Water-Quality Assessment Program for investigations of stream- and ground-water quality. For nitrogen, the largest source was farm fertilizer; for phosphorus, the largest sources were farm fertilizer and livestock manure. Nutrient inputs from fertilizer use in nonfarm areas, while locally important, were an order of magnitude smaller than inputs from other sources. Nutrient inputs from all sources increased between 1987 and 1997, but the relative proportions of nutrients from each source were constant. Farm-fertilizer inputs were highest in the upper Midwest, along eastern coastal areas, and in irrigated areas of the West. Nonfarm-fertilizer use was similar in major metropolitan areas throughout the Nation, but was more extensive in the more populated Eastern and Central States and in California. Areas of greater manure inputs were located throughout the South-central and Southeastern States and in scattered areas of the West. Nitrogen deposition from the atmosphere generally increased from west to east and is related to the location of major sources and the effects of precipitation and prevailing winds. These nutrient-loading data at the county level are expected to be the fundamental basis for national and regional assessments of water quality for the National Water-Quality Assessment Program and other large-scale programs.

Environmental Analysis of U.S. Navy Submarine Solid Waste Discharges. Report of Findings

DTIC Science & Technology

1997-05-01

compared to background organic matter. All of this indicates that the material will not be a significant source of nutrients in the water column or the...influents ( Wastewater Chemistry Laboratory, 1994) or in discharge effluent not subjected to primary treatment (Pyewipe, 1992-1994). The amount of...be found in the shallow waters of the Mediterranean Sea. Under cold (4°q, non- nutrient limiting conditions, such as those that might be found in the

Watershed-Scale Cover Crops Reduce Nutrient Export From Agricultural Landscapes.

NASA Astrophysics Data System (ADS)

Tank, J. L.; Hanrahan, B.; Christopher, S. F.; Trentman, M. T.; Royer, T. V.; Prior, K.

2016-12-01

The Midwestern US has undergone extensive land use change as forest, wetlands, and prairies have been converted to agroecosystems. Today, excess fertilizer nutrients from farm fields enter Midwestern agricultural streams, which degrades both local and downstream water quality, resulting in algal blooms and subsequent hypoxic "dead zones" far from the nutrient source. We are quantifying the benefits of watershed-scale conservation practices that may reduce nutrient runoff from adjacent farm fields. Specifically, research is lacking on whether the planting of winter cover crops in watersheds currently dominated by row-crop agriculture can significantly reduce nutrient inputs to adjacent streams. Since 2013, farmers have planted cover crops on 70% of croppable acres in the Shatto Ditch Watershed (IN), and "saturation level" implementation of this conservation practice has been sustained for 3 years. Every 14 days, we have quantified nutrient loss from fields by sampling nutrient fluxes from multiple subsurface tile drains and longitudinally along the stream channel throughout the watershed. Cover crops improved stream water quality by reducing dissolved inorganic nutrients exported downstream; nitrate-N and DRP concentrations and fluxes were significantly lower in tiles draining fields with cover crops compared to those without. Annual watershed nutrient export also decreased, and reductions in N and P loss ( 30-40%) exceeded what we expected based on only a 6-10% reduction in runoff due to increased watershed water holding capacity. We are also exploring the processes responsible for increased nutrient retention, where they are occurring (terrestrial vs. aquatic) and when (baseflow vs. storms). For example, whole-stream metabolism also responded to cover crop planting, showing reduced variation in primary production and respiration in years after watershed-scale planting of cover crops. In summary, widespread land cover change, through cover crop planting, can significantly reduce annual watershed-scale nutrient export. Moreover, successful outcomes highlighted through demonstration projects may facilitate widespread adoption, making them powerful agents of change for advancing conservation success.

Nitrogen and phosphorus exports from high rainfall zone cropping in Australia: issues and opportunities for research.

PubMed

Mathers, Nicole J; Nash, David M; Gangaiya, Philomena

2007-01-01

Cropping is one of the many industries contributing to the excessive loading of nitrogen (N) and phosphorus (P) to rivers and lakes in Australia. Nitrogen and P exports from cropping systems have not been systematically investigated to the same extent as those from other agricultural sectors, such as dairy pastures. Therefore, this review relies heavily on information derived from agronomy and other fundamental studies on soil-nutrient interactions to determine the potential for nutrient export from high rainfall zone (HRZ) cropping. There is a great deal of variation in environmental and management strategies across cropping in the HRZ, which suggests that nutrient exports could occur under a range of scenarios. The potential for exports is therefore discussed within a conceptual framework of nutrient sources, mechanisms for mobilization, and transport pathways in HRZ cropping. Transport refers to nutrient movement by flowing water after it has been mobilized, and export refers to the transfer of nutrients from one landscape compartment (e.g., a soil) to another (e.g., a stream or lake). The transport of nutrients from HRZ cropping can occur through surface and/or subsurface pathways depending on factors such as landform and infiltration and nutrient sorption characteristics of the soil profile. Surface pathways are likely to be more significant for phosphorus. For N, subsurface movement is likely to be as significant as surface movement because nitrates are generally not bound by most soils. Information about mechanisms of nutrient mobilization is essential for developing management strategies to control nutrient exports from HRZ cropping.

Plant Biomass Leaching for Nutrient Recovery in Closed Loop Systems Project

NASA Technical Reports Server (NTRS)

Zeitlin, Nancy P.; Wheeler, Raymond (Compiler); Lunn, Griffin

2015-01-01

Plants will be important for food and O2 production during long term human habitation in space. Recycling of nutrients (e.g., from waste materials) could reduce the resupply costs of fertilizers for growing these plants. Work at NASA's Kennedy Space Center has shown that ion exchange resins can extract fertilizer (plant essential nutrients) from human waste water, after which the residual brine could be treated with electrodialysis to recover more water and produce high value chemicals (e.g., acids and bases). In habitats with significant plant production, inedible biomass becomes a major source of solid waste. To "close the loop" we also need to recover useful nutrients and fertilizer from inedible biomass. We are investigating different approaches to retrieve nutrients from inedible plant biomass, including physical leaching with water, processing the biomass in bioreactors, changing the pH of leaching processing, and/or conducting multiple leaches of biomass residues.

Sewage input reduces the consumption of Rhizophora mangle propagules by crabs in a subtropical mangrove system.

PubMed

Boehm, Frederike Ricarda; Sandrini-Neto, Leonardo; Moens, Tom; da Cunha Lana, Paulo

2016-12-01

Mangrove forests are highly productive and play a major role in global carbon cycling. Their carbon accumulation can be influenced through the consumption of nutrient-poor leaves and propagules by herbivore crabs. Anthropogenic nutrient input from sewage contamination is widespread in these often naturally nutrient-limited ecosystems. We hypothesised that sewage-mediated nutrient input to mangrove stands of Paranaguá Bay (southern Brazil), would alter the nutrient sources available for crabs, e.g. through microphytobenthos increase, and that this would reflect in their feeding behaviour. We predicted that propagules of Rhizophora mangle in contaminated stands would experience lower grazing pressure from their two main local consumers (Ucides cordatus and Goniopsis cruentata). We compared herbivory rates on R. mangle propagules in sewage contaminated and uncontaminated mangrove stands. We found that herbivory rates were significantly lower in contaminated than uncontaminated forests, but this pattern could not be clearly attributed to increased nutrient availability. Copyright © 2016 Elsevier Ltd. All rights reserved.

Digital data used to relate nutrient inputs to water quality in the Chesapeake Bay watershed, version 3.0

USGS Publications Warehouse

Brakebill, John W.; Preston, Stephen D.

2004-01-01

Chesapeake Bay restoration efforts are focused on improving water quality, living resources, and ecological habitats by 2010. One aspect of the water-quality restoration is the refinement of strategies designed to implement nutrient-reduction practices within the Bay watershed. These strategies are being refined and implemented by resource managers of the Chesapeake Bay Program (CBP), a partnership comprised of various Federal, State, and local agencies that includes jurisdictions within Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia, and the District of Columbia. The U.S. Geological Survey (USGS), an active member of the CBP, provides necessary water-quality information for these Chesapeake Bay nutrient-reduction strategy revisions and evaluations. The formulation and revision of effective nutrient-reduction strategies requires detailed scientific information and an analytical understanding of the sources, transport, and delivery of nutrients to the Chesapeake Bay. The USGS is supporting these strategies by providing scientific information to resource managers that can help them evaluate and understand these processes. One statistical model available to resource managers is a collection of SPAtially Referenced Regressions On Watershed (SPARROW) attributes, which uses a nonlinear regression approach to spatially relate nutrient sources and watershed characteristics to nutrient loads of streams throughout the Chesapeake Bay watershed. Developed by the USGS, information generated by SPARROW can help resource managers determine the geographical distribution and relative contribution of nutrient sources and the factors that affect their transport to the Bay. Nutrient source information representing the late 1990s time period was obtained from several agencies and used to create and compile digital spatial datasets of total nitrogen and total phosphorus contributions that served as input sources to the SPARROW models. These data represent atmospheric deposition, point-source locations, land-use, land-cover, and agricultural sources such as commercial fertilizer and manure applications. Watershed-characteristics datasets representing factors that affect the transport of nutrients also were compiled from previous applications of the SPARROW models in the Chesapeake Bay watershed. Datasets include average-annual precipitation and temperature, slope, soil permeability, and hydrogeomorphic regions. Nutrient-input and watershed-characteristics datasets representing conditions during the late 1990s were merged with a connected network of stream reaches and watersheds to provide the spatial detail required by SPARROW. Stream-nutrient load estimates for 125 sampling sites (87 for total nitrogen and 103 for total phosphorus) served as the dependent variables for the regressions, and were used to calibrate models of total nitrogen and total phosphorus depicting late 1990s conditions in the Chesapeake Bay watershed. Spatial data generated for the models can be used to identify the location of nutrient sources, while the models' nutrient estimates can be used to evaluate stream-nutrient load contributed locally by each source evaluated, the amount of local load generated that is transported to the Bay, and the factors that affect the nutrient transport. Applying the SPARROW methodology to late 1990s information completes three time periods (late 1980s, early 1990s, and late 1990s) of viable data that resource managers can use to evaluate the water-quality conditions within the Bay watershed in order to refine restoration goals and nutrient-reduction strategies.

ROLE OF OCEANIC AND RIVERINE SOURCES IN NUTRIENT AND PHYTOPLANKTON DYNAMICS IN YAQUINA BAY, OREGON

EPA Science Inventory

There is evidence that coastal ecosystems are experiencing environmental problems due to excess nutrients. The numerous sources, forms, and pathways of nutrients make it difficult to determine the effect of increases in anthropogenic loading. This is particularly evident in Pac...

Aerosols in atmospheric chemistry and biogeochemical cycles of nutrients

NASA Astrophysics Data System (ADS)

Kanakidou, Maria; Myriokefalitakis, Stelios; Tsigaridis, Kostas

2018-06-01

Atmospheric aerosols have complex and variable compositions and properties. While scientific interest is centered on the health and climatic effects of atmospheric aerosols, insufficient attention is given to their involvement in multiphase chemistry that alters their contribution as carriers of nutrients in ecosystems. However, there is experimental proof that the nutrient equilibria of both land and marine ecosystems have been disturbed during the Anthropocene period. This review study first summarizes our current understanding of aerosol chemical processing in the atmosphere as relevant to biogeochemical cycles. Then it binds together results of recent modeling studies based on laboratory and field experiments, focusing on the organic and dust components of aerosols that account for multiphase chemistry, aerosol ageing in the atmosphere, nutrient (N, P, Fe) emissions, atmospheric transport, transformation and deposition. The human-driven contribution to atmospheric deposition of these nutrients, derived by global simulations using past and future anthropogenic emissions of pollutants, is put into perspective with regard to potential changes in nutrient limitations and biodiversity. Atmospheric deposition of nutrients has been suggested to result in human-induced ecosystem limitations with regard to specific nutrients. Such modifications favor the development of certain species against others and affect the overall functioning of ecosystems. Organic forms of nutrients are found to contribute to the atmospheric deposition of the nutrients N, P and Fe by 20%–40%, 35%–45% and 7%–18%, respectively. These have the potential to be key components of the biogeochemical cycles since there is initial proof of their bioavailability to ecosystems. Bioaerosols have been found to make a significant contribution to atmospheric sources of N and P, indicating potentially significant interactions between terrestrial and marine ecosystems. These results deserve further experimental and modeling studies to reduce uncertainties and understand the feedbacks induced by atmospheric deposition of nutrients to ecosystems.

Benthic nutrient sources to hypereutrophic upper Klamath Lake, Oregon, USA.

PubMed

Kuwabara, James S; Topping, Brent R; Lynch, Dennis D; Carter, James L; Essaid, Hedeff I

2009-03-01

Three collecting trips were coordinated in April, May, and August 2006 to sample the water column and benthos of hypereutrophic Upper Klamath Lake (OR, USA) through the annual cyanophyte bloom of Aphanizomenon flos-aquae. A pore-water profiler was designed and fabricated to obtain the first high-resolution (centimeter-scale) estimates of the vertical concentration gradients of macro- and micronutrients for diffusive-flux determinations. A consistently positive benthic flux for soluble reactive phosphorus (SRP) was observed with solute release from the sediment, ranging between 0.4 and 6.1 mg/m(2)/d. The mass flux over an approximate 200-km(2) lake area was comparable in magnitude to riverine inputs. An additional concern related to fish toxicity was identified when dissolved ammonium also displayed consistently positive benthic fluxes of 4 to 134 mg/m(2)/d, again comparable to riverine inputs. Although phosphorus was a logical initial choice by water quality managers for the limiting nutrient when nitrogen-fixing cyanophytes dominate, initial trace-element results from the lake and major inflowing tributaries suggested that the role of iron limitation on primary productivity should be investigated. Dissolved iron became depleted in the lake water column during the course of the algal bloom, while dissolved ammonium and SRP increased. Elevated macroinvertebrate densities, at least of the order of 10(4) individuals/m(2), suggested that the diffusive-flux estimates may be significantly enhanced by bioturbation. In addition, heat-flux modeling indicated that groundwater advection of nutrients could also significantly contribute to internal nutrient loading. Accurate environmental assessments of lentic systems and reasonable expectations for point-source management require quantitative consideration of internal solute sources.

Benthic nutrient sources to hypereutrophic Upper Klamath Lake, Oregon, USA

USGS Publications Warehouse

Kuwabara, J.S.; Topping, B.R.; Lynch, D.D.; Carter, J.L.; Essaid, H.I.

2009-01-01

Three collecting trips were coordinated in April, May, and August 2006 to sample the water column and benthos of hypereutrophic Upper Klamath Lake (OR, USA) through the annual cyanophyte bloom of Aphanizomenon flos-aquae. A porewater profiler was designed and fabricated to obtain the first high-resolution (centimeter-scale) estimates of the vertical, concentration gradients of macro- and micronutrients for diffusive-flux determinations. A consistently positive benthic flux for soluble reactive phosphorus (SRP) was observed with solute release from the sediment, ranging between 0.4 and 6.1 mg/m2/d. The mass flux over an approximate 200-km2 lake area was comparable in magnitude to riverine inputs. An additional concern, related to fish toxicity was identified when dissolved ammonium also displayed consistently positive benthic fluxes of 4 to 134 mg/m2/d, again, comparable to riverine inputs. Although phosphorus was a logical initial choice by water quality managers for the limiting nutrient when nitrogen-fixing cyanophytes dominate, initial trace-element results from the lake and major inflowing tributaries suggested that the role of iron limitation on primary productivity should be investigated. Dissolved iron became depleted in the lake water column during the course of the algal bloom, while dissolved ammonium and SRP increased. Elevated macroinvertebrate densities, at least of the order of 104 individuals/m2, suggested, that the diffusive-flux estimates may be significantly enhanced, by bioturbation. In addition, heat-flux modeling indicated that groundwater advection of nutrients could also significantly contribute to internal nutrient loading. Accurate environmental assessments of lentic systems and reasonable expectations for point-source management require quantitative consideration of internal solute sources ?? 2009 SETAC.

Nutrient Budgets Calculated in Floodwaters Using a Whole-Ecosystem Experimental Manipulation

NASA Astrophysics Data System (ADS)

Talbot, C. J.; Paterson, M. J.; Xenopoulos, M. A.

2017-12-01

Flooding provides pathways for nutrients to move into surface waters and alter nutrient concentrations, therefore influencing downstream ecosystems and increasing events of eutrophication. Nutrient enrichment will likely affect water quality, primary production, and overall ecosystem function. Quantifying nutrient movement post-flood will help evaluate the risks or advantages that flooding will have on ecosystem processes. Here we constructed nutrient budgets using data collected as part of the Flooded Upland Dynamics Experiment (FLUDEX) at the Experimental Lakes Area (ELA) in northwestern Ontario. Three experimental reservoirs with varying amounts of stored carbon were created by flooding forested land from May through September annually from 1999 to 2003. Organic matter became a significant source of nutrients under flooded conditions and elevated reservoir total nitrogen (TN) and total phosphorus (TP) concentrations within one week of flooding. The highest TN (2.6 mg L-1) and TP (579 µg L-1) concentrations throughout the entire flooding experiment occurred in the medium carbon reservoir within the first two weeks of flooding in 1999. TN and TP fluxes were positive in all years of flooding. TP fluxes decreased after each flooding season therefore, TP production may be less problematic in floodplains subject to frequent repeated flooding. However, TN fluxes remained large even after repeated flooding. Therefore, flooding, whether naturally occurring or from anthropogenic flow alteration, may be responsible for producing significant amounts of nitrogen and phosphorus in aquatic ecosystems.

Increased nutrient concentrations in Lake Erie tributaries influenced by greenhouse agriculture.

PubMed

Maguire, Timothy J; Wellen, Christopher; Stammler, Katie L; Mundle, Scott O C

2018-08-15

Greenhouse production of vegetables is a growing global trade. While greenhouses are typically captured under regulations aimed at farmland, they may also function as a point source of effluent. In this study, the cumulative impacts greenhouse effluents have on riverine macronutrient and trace metal concentrations were examined. Water samples were collected Bi-weekly for five years from 14 rivers in agriculturally dominated watersheds in southwestern Ontario. Nine of the watersheds contained greenhouses with their boundaries. Greenhouse influenced rivers had significantly higher concentrations of macronutrients (nitrogen, phosphorus, and potassium) and trace metals (copper, molybdenum, and zinc). Concentrations within greenhouse influenced rivers appeared to decrease over the 5-year study while concentrations within non-greenhouse influenced river remained constant. The different temporal pattern between river types was attributed to increased precipitation during the study period. Increases in precipitation diluted concentrations in greenhouse influenced rivers; however, non-influenced river runoff proportionally increased nutrient mobility and flow, stabilizing the observed concentrations of non-point sources. Understanding the dynamic nature of environmental releases of point and non-point sources of nutrients and trace metals in mixed agricultural systems using riverine water chemistry is complicated by changes in climatic conditions, highlighting the need for long-term monitoring of nutrients, river flows and weather data in assessing these agricultural sectors. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Submarine groundwater discharge as a major source of nutrients to the Mediterranean Sea

PubMed Central

Garcia-Orellana, Jordi; Masqué, Pere; Feldman, Mor; Weinstein, Yishai

2015-01-01

The Mediterranean Sea (MS) is a semienclosed basin that is considered one of the most oligotrophic seas in the world. In such an environment, inputs of allochthonous nutrients and micronutrients play an important role in sustaining primary productivity. Atmospheric deposition and riverine runoff have been traditionally considered the main external sources of nutrients to the MS, whereas the role of submarine groundwater discharge (SGD) has been largely ignored. However, given the large Mediterranean shore length relative to its surface area, SGD may be a major conveyor of dissolved compounds to the MS. Here, we used a 228Ra mass balance to demonstrate that the total SGD contributes up to (0.3–4.8)⋅1012 m3⋅y−1 to the MS, which appears to be equal or larger by a factor of 16 to the riverine discharge. SGD is also a major source of dissolved inorganic nutrients to the MS, with median annual fluxes of 190⋅109, 0.7⋅109, and 110⋅109 mol for nitrogen, phosphorous, and silica, respectively, which are comparable to riverine and atmospheric inputs. This corroborates the profound implications that SGD may have for the biogeochemical cycles of the MS. Inputs of other dissolved compounds (e.g., iron, carbon) via SGD could also be significant and should be investigated. PMID:25775554

Submarine groundwater discharge as a major source of nutrients to the Mediterranean Sea.

PubMed

Rodellas, Valentí; Garcia-Orellana, Jordi; Masqué, Pere; Feldman, Mor; Weinstein, Yishai

2015-03-31

The Mediterranean Sea (MS) is a semienclosed basin that is considered one of the most oligotrophic seas in the world. In such an environment, inputs of allochthonous nutrients and micronutrients play an important role in sustaining primary productivity. Atmospheric deposition and riverine runoff have been traditionally considered the main external sources of nutrients to the MS, whereas the role of submarine groundwater discharge (SGD) has been largely ignored. However, given the large Mediterranean shore length relative to its surface area, SGD may be a major conveyor of dissolved compounds to the MS. Here, we used a (228)Ra mass balance to demonstrate that the total SGD contributes up to (0.3-4.8)⋅10(12) m(3) ⋅ y(-1) to the MS, which appears to be equal or larger by a factor of 16 to the riverine discharge. SGD is also a major source of dissolved inorganic nutrients to the MS, with median annual fluxes of 190⋅10(9), 0.7⋅10(9), and 110⋅10(9) mol for nitrogen, phosphorous, and silica, respectively, which are comparable to riverine and atmospheric inputs. This corroborates the profound implications that SGD may have for the biogeochemical cycles of the MS. Inputs of other dissolved compounds (e.g., iron, carbon) via SGD could also be significant and should be investigated.

Carbon footprint of urban source separation for nutrient recovery.

PubMed

Kjerstadius, H; Bernstad Saraiva, A; Spångberg, J; Davidsson, Å

2017-07-15

Source separation systems for the management of domestic wastewater and food waste has been suggested as more sustainable sanitation systems for urban areas. The present study used an attributional life cycle assessment to investigate the carbon footprint and potential for nutrient recovery of two sanitation systems for a hypothetical urban area in Southern Sweden. The systems represented a typical Swedish conventional system and a possible source separation system with increased nutrient recovery. The assessment included the management chain from household collection, transport, treatment and final return of nutrients to agriculture or disposal of the residuals. The results for carbon footprint and nutrient recovery (phosphorus and nitrogen) concluded that the source separation system could increase nutrient recovery (0.30-0.38 kg P capita -1 year -1 and 3.10-3.28 kg N capita -1 year -1 ), while decreasing the carbon footprint (-24 to -58 kg CO 2 -eq. capita -1 year -1 ), compared to the conventional system. The nutrient recovery was increased by the use of struvite precipitation and ammonium stripping at the wastewater treatment plant. The carbon footprint decreased, mainly due to the increased biogas production, increased replacement of mineral fertilizer in agriculture and less emissions of nitrous oxide from wastewater treatment. In conclusion, the study showed that source separation systems could potentially be used to increase nutrient recovery from urban areas, while decreasing the climate impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

Iron and nutrient content of wind-erodible sediment in the ephemeral river valleys of Namibia

NASA Astrophysics Data System (ADS)

Dansie, A. P.; Wiggs, G. F. S.; Thomas, D. S. G.

2017-08-01

Research concerning the global distribution of aeolian dust sources has principally focussed on salt/clay pan and desiccated lacustrine emission areas. In southern Africa such sources are identified as Etosha Pan in northern Namibia and Makgadikgadi Pans in northern Botswana. Dust emitting from ephemeral river valleys, however, has been largely overlooked. Rivers are known nutrient transport pathways and the flooding regimes of ephemeral river valleys frequently replenish stores of fine sediment which, on drying, can become susceptible to aeolian erosion. Such airborne sediment may be nutrient rich and thus be significant for the fertilisation of marine waters once deposited. This study investigates the dust source sediments from three ephemeral river valleys in Namibia in terms of their particle size distribution and their concentrations of bioavailable N, P and Fe. We compare the nutrient content of these sediments from the ephemeral river valleys to those collected from Etosha and Makgadikgadi Pans and consider their relative ocean fertilising potential. Our results show that the ephemeral river valleys contain fine grained sediment similar in physical character to Etosha and Makgadikgadi Pans yet they have up to 43 times greater concentrations of bioavailable iron and enriched N and P macronutrients that are each important for ocean fertilisation. The known dust-emitting river valleys of Namibia may therefore be contributing a greater fertilisation role in the adjacent marine system than previously considered, and not-yet investigated. Given this finding a re-assessment of the potential role of ephemeral river valleys in providing nutrient-rich sediment into the aeolian and marine systems in other dryland areas is necessary.

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.

Contribution of Wastewater Treatment Plant Effluents to Nutrient Dynamics in Aquatic Systems: A Review

NASA Astrophysics Data System (ADS)

Carey, Richard O.; Migliaccio, Kati W.

2009-08-01

Excessive nutrient loading (considering nitrogen and phosphorus) is a major ongoing threat to water quality and here we review the impact of nutrient discharges from wastewater treatment plants (WWTPs) to United States (U.S.) freshwater systems. While urban and agricultural land uses are significant nonpoint nutrient contributors, effluent from point sources such as WWTPs can overwhelm receiving waters, effectively dominating hydrological characteristics and regulating instream nutrient processes. Population growth, increased wastewater volumes, and sustainability of critical water resources have all been key factors influencing the extent of wastewater treatment. Reducing nutrient concentrations in wastewater is an important aspect of water quality management because excessive nutrient concentrations often prevent water bodies from meeting designated uses. WWTPs employ numerous physical, chemical, and biological methods to improve effluent water quality but nutrient removal requires advanced treatment and infrastructure that may be economically prohibitive. Therefore, effluent nutrient concentrations vary depending on the particular processes used to treat influent wastewater. Increasingly stringent regulations regarding nutrient concentrations in discharged effluent, along with greater freshwater demand in populous areas, have led to the development of extensive water recycling programs within many U.S. regions. Reuse programs provide an opportunity to reduce or eliminate direct nutrient discharges to receiving waters while allowing for the beneficial use of reclaimed water. However, nutrients in reclaimed water can still be a concern for reuse applications, such as agricultural and landscape irrigation.

Energy trade-offs between intensive biomass utilization, site productivity loss, and ameliorative treatments in loblolly pine plantations

Treesearch

D. Andrew Scott; Thomas J. Dean

2006-01-01

Loblolly pine plantations are the most important source of forest products in the US and the slash remaining after conventional harvest represents a significant potential source of bioenergy. However, slash removal in intensive harvests might, under some circumstances, reduce site productivity by reducing soil organic matter and associated nutrients. Two complimentary...

Effects of nutrient load on microbial activities within a seagrass-dominated ecosystem: Implications of changes in seagrass blue carbon.

PubMed

Liu, Songlin; Jiang, Zhijian; Wu, Yunchao; Zhang, Jingping; Arbi, Iman; Ye, Feng; Huang, Xiaoping; Macreadie, Peter Ian

2017-04-15

Nutrient loading is a leading cause of global seagrass decline, triggering shifts from seagrass- to macroalgal-dominance. Within seagrass meadows of Xincun Bay (South China Sea), we found that nutrient loading (due to fish farming) increased sediment microbial biomass and extracellular enzyme activity associated with carbon cycling (polyphenol oxidase, invertase and cellulase), with a corresponding decrease in percent sediment organic carbon (SOC), suggesting that nutrients primed microorganism and stimulated SOC remineralization. Surpisingly, however, the relative contribution of seagrass-derived carbon to bacteria (δ 13 C bacteria ) increased with nutrient loading, despite popular theory being that microbes switch to consuming macroalgae which are assumed to provide a more labile carbon source. Organic carbon sources of fungi were unaffected by nutrient loading. Overall, this study suggests that nutrient loading changes the relative contribution of seagrass and algal sources to SOC pools, boosting sediment microbial biomass and extracellular enzyme activity, thereby possibly changing seagrass blue carbon. Copyright © 2017 Elsevier Ltd. All rights reserved.

9 CFR 317.354 - Nutrient content claims for “good source,” “high,” and “more.”

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Nutrient content claims for âgood... Nutrition Labeling § 317.354 Nutrient content claims for “good source,” “high,” and “more.” (a) General... nutrient content claims in § 317.313; and (3) The product for which the claim is made is labeled in...

9 CFR 381.454 - Nutrient content claims for “good source,” “high,” and “more.”

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Nutrient content claims for âgood... Nutrition Labeling § 381.454 Nutrient content claims for “good source,” “high,” and “more.” (a) General... nutrient content claims in § 381.413; and (3) The product for which the claim is made is labeled in...

Growth impacts of Saharan dust, mineral nutrients, and CO2 on a planktonic herbivore in southern Mediterranean lakes.

PubMed

Villar-Argaiz, Manuel; Cabrerizo, Marco J; González-Olalla, Juan Manuel; Valiñas, Macarena S; Rajic, Sanja; Carrillo, Presentación

2018-05-17

Rising levels of CO 2 can boost plant biomass but reduce its quality as a food source for herbivores. However, significant uncertainties remain as to the degree to which the effect is modulated by other environmental factors and the underlying processes causing these responses in nature. To address these questions, we carried out CO 2 -manipulation experiments using natural seston from three lakes under nutrient-enriched conditions (mimicking eutrophication and atmospheric dust-input processes) as a food source for the planktonic Daphnia pulicaria. Contrary to expectations, there were no single effects of rising CO 2 on herbivorous growth. Instead, synergistic CO 2  × nutrient interactions indicated that CO 2 did not support higher zooplankton growth rates unless supplemented with dust or inorganic nutrients (nitrogen, N; phosphorus, P) in two of three studied lakes. The overall positive correlation between zooplankton growth and seston carbon (C), but not seston C:P, suggested that this was a food quantity-mediated response. In addition, we found that this correlation improved when the data were grouped according to the nutrient treatments, and that the response was largest for dust. The synergistic CO 2  × nutrient effects reported here imply that the effects of rising CO 2 levels on herbivorous growth may be strongly influenced by eutrophication processes and the increase in dust deposition predicted for the Mediterranean region. Copyright © 2018 Elsevier B.V. All rights reserved.

Greenland's glacial fjords and their role in regional biogeochemical dynamics.

NASA Astrophysics Data System (ADS)

Crosby, J.; Arndt, S.

2017-12-01

Greenland's coastal fjords serve as important pathways that connect the Greenland Ice Sheet (GrIS) and the surrounding oceans. They export seasonal glacial meltwater whilst being significant sites of primary production. These fjords are home to some of the most productive ecosystems in the world and possess high socio-economic value via fisheries. A growing number of studies have proposed the GrIS as an underappreciated yet significant source of nutrients to surrounding oceans. Acting as both transfer routes and sinks for glacial nutrient export, fjords have the potential to act as significant biogeochemical processors, yet remain underexplored. Critically, an understanding of the quantitative contribution of fjords to carbon and nutrient budgets is lacking, with large uncertainties associated with limited availability of field data and the lack of robust upscaling approaches. To close this knowledge gap we developed a coupled 2D physical-biogeochemical model of the Godthåbsfjord system, a sub-Arctic sill fjord in southwest Greenland, to quantitatively assess the impact of nutrients exported from the GrIS on fjord primary productivity and biogeochemical dynamics. Glacial meltwater is found to be a key driver of fjord-scale circulation patterns, whilst tracer simulations reveal the relative nutrient contributions from meltwater-driven upwelling and meltwater export from the GrIS. Hydrodynamic circulation patterns and freshwater transit times are explored to provide a first understanding of the glacier-fjord-ocean continuum, demonstrating the complex pattern of carbon and nutrient cycling at this critical land-ocean interface.

Nitrogen regulation of transpiration controls mass-flow acquisition of nutrients.

PubMed

Matimati, Ignatious; Verboom, G Anthony; Cramer, Michael D

2014-01-01

Transpiration may enhance mass-flow of nutrients to roots, especially in low-nutrient soils or where the root system is not extensively developed. Previous work suggested that nitrogen (N) may regulate mass-flow of nutrients. Experiments were conducted to determine whether N regulates water fluxes, and whether this regulation has a functional role in controlling the mass-flow of nutrients to roots. Phaseolus vulgaris were grown in troughs designed to create an N availability gradient by restricting roots from intercepting a slow-release N source, which was placed at one of six distances behind a 25 μm mesh from which nutrients could move by diffusion or mass-flow (termed 'mass-flow' treatment). Control plants had the N source supplied directly to their root zone so that N was available through interception, mass-flow, and diffusion (termed 'interception' treatment). 'Mass-flow' plants closest to the N source exhibited 2.9-fold higher transpiration (E), 2.6-fold higher stomatal conductance (gs), 1.2-fold higher intercellular [CO2] (Ci), and 3.4-fold lower water use efficiency than 'interception' plants, despite comparable values of photosynthetic rate (A). E, gs, and Ci first increased and then decreased with increasing distance from the N source to values even lower than those of 'interception' plants. 'Mass-flow' plants accumulated phosphorus and potassium, and had maximum concentrations at 10mm from the N source. Overall, N availability regulated transpiration-driven mass-flow of nutrients from substrate zones that were inaccessible to roots. Thus when water is available, mass-flow may partially substitute for root density in providing access to nutrients without incurring the costs of root extension, although the efficacy of mass-flow also depends on soil nutrient retention and hydraulic properties.

Nitrogen regulation of transpiration controls mass-flow acquisition of nutrients

PubMed Central

Matimati, Ignatious

2014-01-01

Transpiration may enhance mass-flow of nutrients to roots, especially in low-nutrient soils or where the root system is not extensively developed. Previous work suggested that nitrogen (N) may regulate mass-flow of nutrients. Experiments were conducted to determine whether N regulates water fluxes, and whether this regulation has a functional role in controlling the mass-flow of nutrients to roots. Phaseolus vulgaris were grown in troughs designed to create an N availability gradient by restricting roots from intercepting a slow-release N source, which was placed at one of six distances behind a 25 μm mesh from which nutrients could move by diffusion or mass-flow (termed ‘mass-flow’ treatment). Control plants had the N source supplied directly to their root zone so that N was available through interception, mass-flow, and diffusion (termed ‘interception’ treatment). ‘Mass-flow’ plants closest to the N source exhibited 2.9-fold higher transpiration (E), 2.6-fold higher stomatal conductance (g s), 1.2-fold higher intercellular [CO2] (C i), and 3.4-fold lower water use efficiency than ‘interception’ plants, despite comparable values of photosynthetic rate (A). E, g s, and C i first increased and then decreased with increasing distance from the N source to values even lower than those of ‘interception’ plants. ‘Mass-flow’ plants accumulated phosphorus and potassium, and had maximum concentrations at 10mm from the N source. Overall, N availability regulated transpiration-driven mass-flow of nutrients from substrate zones that were inaccessible to roots. Thus when water is available, mass-flow may partially substitute for root density in providing access to nutrients without incurring the costs of root extension, although the efficacy of mass-flow also depends on soil nutrient retention and hydraulic properties. PMID:24231035

The effect of nitrogen loading on a brackish estuarine faunal community: A stable isotope approach

USGS Publications Warehouse

Keats, R.A.; Osher, L.J.; Neckles, H.A.

2004-01-01

Coastal ecosystems worldwide face increased nutrient enrichment from shoreline and watershed development and atmospheric pollution. We investigated the response of the faunal community of a small microtidal estuary dominated by Ruppia maritima (widgeon grass) in Maine, United States, to increased nitrogen loading using an in situ mesocosm enrichment experiment. Community response was characterized by assessing quantitative shifts in macroin-vertebrate community composition and identifying changes in food web structure using stable carbon and nitrogen isotope ratios of producers and consumers. The community was dominated by brackish water invertebrates including midge larvae, oligochaetes, damselfly larvae, amphipods, and ostracods. Experimental nutrient additions resulted in significantly lower densities of herbivorous chironomids and predatory damselflies and greater densities of deposit feeding oligochaetes. Grazing midge larvae (Chironomidae: Dicrotendipes, Cricotopus) consumed epiphytic algae under both natural and enriched conditions. Deposit feeding Chironomus was dependent on allochthonous sources of detritus under natural conditions and exhibited a shift to autochthonous sources of detritus under enriched conditions. Predatory Enallagma primarily consumed grazing chironomids under all but the highest loading conditions. Experimental nutrient loading resulted in an increase in generalist deposit feeders dependent on autochthonous sources of detritus.

Nutrient sources and transport in the Missouri River Basin, with emphasis on the effects of irrigation and reservoirs

USGS Publications Warehouse

Brown, J.B.; Sprague, L.A.; Dupree, J.A.

2011-01-01

SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were used to relate instream nutrient loads to sources and factors influencing the transport of nutrients in the Missouri River Basin. Agricultural inputs from fertilizer and manure were the largest nutrient sources throughout a large part of the basin, although atmospheric and urban inputs were important sources in some areas. Sediment mobilized from stream channels was a source of phosphorus in medium and larger streams. Irrigation on agricultural land was estimated to decrease the nitrogen load reaching the Mississippi River by as much as 17%, likely as a result of increased anoxia and denitrification in the soil zone. Approximately 16% of the nitrogen load and 33% of the phosphorus load that would have otherwise reached the Mississippi River was retained in reservoirs and lakes throughout the basin. Nearly half of the total attenuation occurred in the eight largest water bodies. Unlike the other major tributary basins, nearly the entire instream nutrient load leaving the outlet of the Platte and Kansas River subbasins reached the Mississippi River. Most of the larger reservoirs and lakes in the Platte River subbasin are upstream of the major sources, whereas in the Kansas River subbasin, most of the source inputs are in the southeast part of the subbasin where characteristics of the area and proximity to the Missouri River facilitate delivery of nutrients to the Mississippi River.

Nutrient Sources and Transport in the Missouri River Basin, with Emphasis on the Effects of Irrigation and Reservoirs1

PubMed Central

Brown, Juliane B; Sprague, Lori A; Dupree, Jean A

2011-01-01

Abstract SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were used to relate instream nutrient loads to sources and factors influencing the transport of nutrients in the Missouri River Basin. Agricultural inputs from fertilizer and manure were the largest nutrient sources throughout a large part of the basin, although atmospheric and urban inputs were important sources in some areas. Sediment mobilized from stream channels was a source of phosphorus in medium and larger streams. Irrigation on agricultural land was estimated to decrease the nitrogen load reaching the Mississippi River by as much as 17%, likely as a result of increased anoxia and denitrification in the soil zone. Approximately 16% of the nitrogen load and 33% of the phosphorus load that would have otherwise reached the Mississippi River was retained in reservoirs and lakes throughout the basin. Nearly half of the total attenuation occurred in the eight largest water bodies. Unlike the other major tributary basins, nearly the entire instream nutrient load leaving the outlet of the Platte and Kansas River subbasins reached the Mississippi River. Most of the larger reservoirs and lakes in the Platte River subbasin are upstream of the major sources, whereas in the Kansas River subbasin, most of the source inputs are in the southeast part of the subbasin where characteristics of the area and proximity to the Missouri River facilitate delivery of nutrients to the Mississippi River. PMID:22457581

Integrating Spatial Land Use Analysis and Mathematical Material Flow Analysis for Nutrient Management: A Case Study of the Bang Pakong River Basin in Thailand

NASA Astrophysics Data System (ADS)

Kupkanchanakul, Wallapa; Kwonpongsagoon, Suphaphat; Bader, Hans-Peter; Scheidegger, Ruth

2015-05-01

Rivers in developing and emerging countries often lack good water quality. Tools to assess the water quality in rivers, including identification of possible sources of pollution, are therefore of increasing importance. The aim of this study is to apply mathematical material flow and spatial land use analyses to identify and geographically locate the main nitrogen and phosphorus sources and processes in Bang Pakong Basin (BPB). Potential measures to mitigate the nitrogen and phosphorus loads to the water system can then be efficiently evaluated. The combination of these two methods reveals the overall nutrient load as well as local "hot spots." This allows possible mitigation measures to be discussed with regard to their spatial location. This approach goes beyond previous work in which mathematical material flow analysis was shown to be a useful tool to investigate sources of nutrients regardless of their location. The results show that the main sources contributing nutrients to waterways are aquaculture, such as shrimp, tilapia, catfish, and sea bass farming, as well as rice paddies along the main river. Additional sources contributing nutrients to this basin are field crops, livestock, aquaculture, households, and industry. High levels of nutrient inflows come from feeds and fertilizers through aquaculture and rice cultivation. The excess nutrients run into the waterways by direct discharge from aquaculture and runoff processes from rice paddies. Scenario analysis shows that management practices for aquaculture, rice, pig, and poultry farming are key drivers for reducing nutrients in the BPB.

Integrating spatial land use analysis and mathematical material flow analysis for nutrient management: a case study of the Bang Pakong River Basin in Thailand.

PubMed

Kupkanchanakul, Wallapa; Kwonpongsagoon, Suphaphat; Bader, Hans-Peter; Scheidegger, Ruth

2015-05-01

Rivers in developing and emerging countries often lack good water quality. Tools to assess the water quality in rivers, including identification of possible sources of pollution, are therefore of increasing importance. The aim of this study is to apply mathematical material flow and spatial land use analyses to identify and geographically locate the main nitrogen and phosphorus sources and processes in Bang Pakong Basin (BPB). Potential measures to mitigate the nitrogen and phosphorus loads to the water system can then be efficiently evaluated. The combination of these two methods reveals the overall nutrient load as well as local "hot spots." This allows possible mitigation measures to be discussed with regard to their spatial location. This approach goes beyond previous work in which mathematical material flow analysis was shown to be a useful tool to investigate sources of nutrients regardless of their location. The results show that the main sources contributing nutrients to waterways are aquaculture, such as shrimp, tilapia, catfish, and sea bass farming, as well as rice paddies along the main river. Additional sources contributing nutrients to this basin are field crops, livestock, aquaculture, households, and industry. High levels of nutrient inflows come from feeds and fertilizers through aquaculture and rice cultivation. The excess nutrients run into the waterways by direct discharge from aquaculture and runoff processes from rice paddies. Scenario analysis shows that management practices for aquaculture, rice, pig, and poultry farming are key drivers for reducing nutrients in the BPB.

Patterns and processes of nutrient transfers from land to water: a catchment approach to evaluate Good Agricultural Practice in Ireland

NASA Astrophysics Data System (ADS)

Mellander, P.-E.; Melland, A. R.; Shortle, G.; Wall, D.; Mechan, S.; Buckley, C.; Fealy, R.; Jordan, P.

2009-04-01

Eutrophication of fresh, transitional and coastal waters by excessive nutrient inputs is one of the most widespread water quality problems in developed countries. Sources of nutrient nitrogen (N) and phosphorus (P) can come from a multiplicity of sources and be dependent on numerous hydrological controls from catchments with both urban and agricultural landuses. Aquatic impacts are widely reported as a result of excessive nutrient transfers from land to water and include changes in ecological integrity and loss of amenity. In the European Union, the Water Framework Directive (WFD) and associated Directives are the key structures with which member states must develop national and often trans-national polices to deal with issues of water resources management. The linked Nitrates Directive is particularly concerned with integrating sustainable agriculture and good water quality objectives and is written into national polices. In Ireland this policy is the Nitrates Directive National Action Programme (NAP), Statutory Instruction 378, Good Agricultural Practise regulation, and amongst other things, sets targets and limits on the use of organic and inorganic fertilisers, soil fertility and slurry/fertiliser spreading and cultivation times. To evaluate the effectiveness of this policy, Teagasc, the Irish Agriculture and Food Development Authority, is undertaking a catchment scale audit on sources, sinks, and changes in nutrient use and export over several years. The Agricultural Catchments Programme is based on a science-stakeholder-management partnership to generate knowledge and specifically to protect water quality from nitrogen and phosphorus transfers within the constraints of the requirements of modern Irish agricultural practises. Eight catchments of 5-12 km2 have been selected for the programme to represent a range of agricultural intensities and vulnerabilities to nitrogen and phosphorus loss including catchments that are situated on permeable and impermeable grassland soils; areas where arable production represents a significant landuse; and catchments on productive and unproductive aquifers. The catchments were identified using a GIS-based multicriteria decision analysis with objective criteria that included landuse data (including agricultural and settlement statistics) combined with soils and geology data to evaluate the risk of P and N loss. Shortlisted catchments were then finalised using practical criteria based on the potential for hydrometry and hydrochemistry research. In each catchment, a conceptual model approach is being used to hypothesize the sources, seasonal mobilisation and pathways of nutrients and water through the soil/subsoil system and transfer into surface and ground water systems to stratify each catchment experimental design. Knowledge of the nutrient management of each catchment farm and resulting soil fertility will be used to monitor the sources of agricultural N and P. Environmental soil nutrient tests will provide baselines and checks on the potential for mobilisation. Areas of high soil fertility that are coincident with high surface or sub-surface hydrological connectivity will be monitored for subsequent nutrient transfer. Other potential nutrient source loads within the catchments, such as rural waste-water treatment plants and domestic septic systems, will be factored in as non-agricultural sources. Similarly, the potential for farmyard transfers will also be assessed. The net balance of nutrient transfer at the catchment outlets will be monitored using a high resolution method that is coincident with hydrometric measurements to ensure that there is a full understanding of the inter-dependence between point and diffuse nutrient transfers and hydrodynamics. This source to transfer approach is highly appropriate and a move towards inductive understanding of nutrient use and export in river catchments - the scale at which policies for water resources management will be assessed under the WFD. The data are also highly conducive to constraining catchment scale, distributed models for predicting chemical transfers in runoff. As the Programme is aiming to integrate the often perceived contentious objectives of water quality management with those of sustainable agriculture, farm economics will also be monitored at the same time and an assessment made of farmer attitudes. An advisory programme is also a major component and dedicated farm advisors will ensure that farmers are fully appraised of obligations and opportunities in the National Action Programme.

NONPOINT SOURCES AND WATER QUALITY TRADING

EPA Science Inventory

Management of nonpoint sources (NPS) of nutrients may reduce discharge levels more cost effectively than can additional controls on point sources (PS); water quality trading (WQT), where a PS buys nutrient or sediment reductions from an NPS, may be an alternative means for the PS...

Factors affecting stream nutrient loads: A synthesis of regional SPARROW model results for the continental United States

USGS Publications Warehouse

Preston, Stephen D.; Alexander, Richard B.; Schwarz, Gregory E.; Crawford, Charles G.

2011-01-01

We compared the results of 12 recently calibrated regional SPARROW (SPAtially Referenced Regressions On Watershed attributes) models covering most of the continental United States to evaluate the consistency and regional differences in factors affecting stream nutrient loads. The models - 6 for total nitrogen and 6 for total phosphorus - all provide similar levels of prediction accuracy, but those for major river basins in the eastern half of the country were somewhat more accurate. The models simulate long-term mean annual stream nutrient loads as a function of a wide range of known sources and climatic (precipitation, temperature), landscape (e.g., soils, geology), and aquatic factors affecting nutrient fate and transport. The results confirm the dominant effects of urban and agricultural sources on stream nutrient loads nationally and regionally, but reveal considerable spatial variability in the specific types of sources that control water quality. These include regional differences in the relative importance of different types of urban (municipal and industrial point vs. diffuse urban runoff) and agriculture (crop cultivation vs. animal waste) sources, as well as the effects of atmospheric deposition, mining, and background (e.g., soil phosphorus) sources on stream nutrients. Overall, we found that the SPARROW model results provide a consistent set of information for identifying the major sources and environmental factors affecting nutrient fate and transport in United States watersheds at regional and subregional scales. ?? 2011 American Water Resources Association. This article is a U.S. Government work and is in the public domain in the USA.

Metal and Nutrient Distribution and Fractionation in Managed Urban Watersheds Across the US Southwest

NASA Astrophysics Data System (ADS)

Papelis, C.; Williams, A. C.; Boettcher, T. M.

2008-12-01

Metals, metalloids, and nutrients are common contaminants of concern in arid and semi-arid watersheds in the Southwestern U.S. Because of the dramatic population growth in this part of the U.S., the potential for contamination of urban watersheds has also increased over the last few decades. Streams in urban watersheds receive storm water, urban runoff, shallow groundwater, and treated wastewater, among other sources. In addition, urban watersheds are often heavily managed to mitigate flood events and sediment- related impacts. Sediment transport can have a profound effect on the water quality of affected bodies of water. However, differences in geology, hydrogeology, and land use may have dramatic effects on the distribution of nutrients and metals in different urban watersheds. To test these effects, aqueous and sediment samples were collected above and below erosion control and other structures along two heavily managed urban watersheds, namely the Las Vegas Wash in the Las Vegas Valley Watershed, Nevada, and the Rio Salado (Salt River) in the Phoenix Metropolitan Area, Arizona. The construction of such control structures has the potential to alter the distribution of metals and metalloids in bodies of water used by wildlife. In this study, all sediments were characterized by particle size distribution, specific surface area, mineralogical composition, and scanning electron microscopy. The results of total arsenic, boron, and phosphorus extractions will be discussed, as a function of sediment characteristics. Significant differences exist between the two U.S. Southwest watersheds studied, including land use, water sources, sediment characteristics, nutrient and metal distribution, and overall system complexity. These differences lead to significant variations in metalloid and nutrient distributions in the two watersheds. Differences and similarities in the two systems will be explained as a function of sediment characteristics and watershed properties.

A Catchment Systems Engineering (CSE) approach to managing intensively farmed land

NASA Astrophysics Data System (ADS)

Jonczyk, Jennine; Quinn, Paul; Barber, Nicholas; Wilkinson, Mark; ODonnell, Greg

2014-05-01

Rural land management practices can have a significant impact on the hydrological and nutrient dynamics within a catchment which can dramatically alter the way it processes water, exacerbating nutrient losses from the system. A collaborative and holistic approach for managing potential conflicts between land management activity for food production alongside the aspiration to achieve good water quality and the need to make space for water can ensure the long-term sustainability of our agricultural catchments. Catchment System Engineering (CSE) is an interventionist approach to altering the catchment scale runoff regime through the manipulation of hydrological flow pathways throughout the catchment. By targeting hydrological flow pathways at source, such as overland flow, field drain and ditch function, a significant component of the runoff generation can be managed, greatly reducing erosive soil losses. Coupled with management of farm nutrients at source many runoff attenuation features or measures can be co-located to achieve benefits for water quality. Examples of community-led mitigation measures using the CSE approach will be presented from two catchments in Northumberland, Northern England, that demonstrate the generic framework for identification of multipurpose features that slow, store and filter runoff at strategic locations in the landscape. Measures include within-field barriers, edge of field traps and within-field sediment filters and sediment traps which demonstrate how sediment can be trapped locally (including silt and clay fractions) and be recovered for use back on the land. Deliverables from this CSE approach includes the reduction of downstream flood risk and capturing of sediment and associated nutrients. The CSE approach allows for a more natural flood and nutrient management approach which helps to restore vital catchment functions to re-establish a healthy catchment system.

Developing unique tracers to distinguish nutrient contributions from agriculture and wastewater sources in the Choptank River and Anacostia River watersheds

USDA-ARS?s Scientific Manuscript database

Eutrophication is a major problem for the Chesapeake Bay ecosystem. The efficacy of the restoration efforts implemented is restricted by the inability to differentiate nutrient sources. This study assessed the use of stable tracers in order to discriminate between urban and agricultural nutrient sou...

A 100-year sedimentary record of natural and anthropogenic impacts on a shallow eutrophic lake, Lake Chaohu, China.

PubMed

Zan, Fengyu; Huo, Shouliang; Xi, Beidou; Zhu, Chaowei; Liao, Haiqing; Zhang, Jingtian; Yeager, Kevin M

2012-03-01

In this study, the sediment profiles of total organic carbon, total nitrogen, C/N ratios, total phosphorus, N/P ratios, C/P ratios, particle sizes, and stable carbon and nitrogen isotopes (δ(13)C and δ(15)N) were used to investigate natural and anthropogenic impacts on Lake Chaohu over the past 100 years. Before 1960, Lake Chaohu experienced low productivity and a relatively steady and low nutrient input. The increasing concentration and fluxes of total organic carbon, total nitrogen, total phosphorus, together with changes in the δ(13)C and δ(15)N of organic material in the sediment cores, suggested that the anthropogenic effects on trophic status first started because of an increase in nutrient input caused by a population increase in the drainage area. With the construction of the Chaohu Dam, an increase in the utilization of fertilizer and the population growth which occurred since 1960, stable depositional conditions and increasing nutrient input resulted in a dominantly algae-derived organic matter source and high productivity. Nutrient input increased most significantly around 1980 following the rapidly growing population, with concomitant urbanization, industrial and agricultural development. This study also revealed that the concentration and distribution of nutrients varied between different areas of sediment within Lake Chaohu because of the influence of different drainage basins and pollution sources. This journal is © The Royal Society of Chemistry 2012

Regulation of Hydrolytic Enzyme Activity in Aquatic Microbial Communities Hosted by Carnivorous Pitcher Plants.

PubMed

Young, Erica B; Sielicki, Jessica; Grothjan, Jacob J

2018-04-20

Carnivorous pitcher plants Sarracenia purpurea host diverse eukaryotic and bacterial communities which aid in insect prey digestion, but little is known about the functional processes mediated by the microbial communities. This study aimed to connect pitcher community diversity with functional nutrient transformation processes, identifying bacterial taxa, and measuring regulation of hydrolytic enzyme activity in response to prey and alternative nutrient sources. Genetic analysis identified diverse bacterial taxa known to produce hydrolytic enzyme activities. Chitinase, protease, and phosphatase activities were measured using fluorometric assays. Enzyme activity in field pitchers was positively correlated with bacterial abundance, and activity was suppressed by antibiotics suggesting predominantly bacterial sources of chitinase and protease activity. Fungi, algae, and rotifers observed could also contribute enzyme activity, but fresh insect prey released minimal chitinase activity. Activity of chitinase and proteases was upregulated in response to insect additions, and phosphatase activity was suppressed by phosphate additions. Particulate organic P in prey was broken down, appearing as increasing dissolved organic and inorganic P pools within 14 days. Chitinase and protease were not significantly suppressed by availability of dissolved organic substrates, though organic C and N stimulated bacterial growth, resulting in elevated enzyme activity. This comprehensive field and experimental study show that pitcher plant microbial communities dynamically regulate hydrolytic enzyme activity, to digest prey nutrients to simpler forms, mediating biogeochemical nutrient transformations and release of nutrients for microbial and host plant uptake.

Impacts of transportation infrastructure on storm water and surfaces waters in Chittenden County, Vermont, USA.

DOT National Transportation Integrated Search

2014-06-01

Transportation infrastructure is a major source of stormwater runoff that can alter hydrology and : contribute significant loading of nutrients, sediment, and other pollutants to surface waters. These : increased loads can contribute to impairment of...

Coastal nutrification and coral health at Porto Seguro reefs, Brazil

NASA Astrophysics Data System (ADS)

Costa, O.; Attrill, M.; Nimmo, M.

2003-04-01

Human activities have substantially increased the natural flux of nutrients to coastal systems worldwide. In Brazilian reefs, all major stresses (sedimentation, overfishing, tourism-related activities and nutrification) are human induced. To assess nutrification levels in Brazilian coastal reefs, measurements of the distribution patterns of nutrients and chlorophyll concentrations were conducted in three nearshore and offshore reefs with distinct nutrient inputs along the south coast of Bahia State. Seawater and porewater samples were analysed for soluble reactive phosphorus, total oxidised nitrogen and reactive silica. Benthic surveys were performed at all sites to investigate the relationships between benthic community composition and nutrient and chlorophyll concentrations. Sampling was undertaken in dry and rainy seasons. Results of both seawater and porewater nutrient measurements revealed the occurrence of consistent spatial and temporal patterns. An inshore-offshore gradient reflects the occurrence of land-based point sources, with significant amount of nutrients being delivered by human activities on the coast (untreated sewage and groundwater seepage). Another spatial gradient is related to distance from a localized source of pollution (an urban settlement without sewerage treatment) with two nearshore reefs presenting distinct nutrient and chlorophyll concentrations. Seasonal variations suggest that submarine groundwater discharge (SGD) is the primary source of nutrients for the coastal reefs during rainy season. The data also suggests that the SGD effect is not restricted to nearshore reefs, and may be an important factor controlling the differences between landward and seaward sides on the offshore reef. Benthic community assessment revealed that turf alga is the dominant group in all studied reefs and that zoanthids are the organisms most adapted to take advantage of nutrient increase in coastal areas. At nearshore reefs, there was a negative correlation between zoanthids and algal abundance and a positive correlation with the amount of available space for settlement. On the offshore reef, correlation of algal cover with both zoanthids and available space were negative, suggesting that hard substrate may be the primary limiting factor for algal settlement and growth in the nearshore reefs. Highly variable physical disturbances (like wave energy and low tide exposure) between landward and seaward reef sides appear to be the factors controlling algal distribution in the offshore reef. Highly spatial variability in coral cover ultimately reflects the patchy distribution of stony corals over the reefs.

Modelling the temporal and spatial distribution of ecological variables in Beibu Gulf

NASA Astrophysics Data System (ADS)

Pan, H.; Huang, L.; Yang, S.; Shi, D.; Pan, W.

2017-12-01

Beibu Gulf is an important semi-enclosed gulf located in northern South China Sea. It is rich in natural resources and its coastal rim is undergoing a rapid economic growth in recent years. Study on the spatial and temporal distribution of ecological variables by the influence of physical and biological processes in Beibu Gulf can provide the theoretical basis for the utilization of resources and environmental protection. Based on the MEC three-dimensional hydrodynamic model, a nutrient-phytoplankton-zooplankton-detritus (NPZD) model was applied to simulate the distribution of ecological variables in Beibu Gulf. The result shows that the ecosystem in Beibu Gulf is significantly influenced by dynamic conditions. In autumn and winter, great amount of nutrient-rich water from western Guangdong coastal area passes through Qiongzhou Strait and flows into Beibu Gulf, with about 108.3×103 t of inorganic nitrogen and 3.7×103 t of phosphate annually, leading to phytoplankton bloom. In summer, most of the nutrients come from rivers so high concentrations of nutrients and chlorophyll-a appear on estuaries. The annual net nutrient inputs from South China Sea into Beibu Gulf are 66.6×103 t for inorganic nitrogen and 4.6×103 t for phosphate. Phytoplankton plays an important role in nutrients' refreshment: a) Absorption by the process of photosynthesis is the biggest nutrient sink. b) Cellular release from dead phytoplankton is the biggest source in inorganic budget, making up for 33.4% of nitrogen consumed by photosynthesis while the process of respiration is the biggest source in phosphate budget, making up for 32.4% of phosphorus consumed by photosynthesis. c) Mineralization from detritus is also a considerable supplement of inorganic nutrients. Overall, biological process has more influence than physical process on the nutrient cycle budget in Beibu Gulf. The comparison of the result with remote sensing and in-situ data indicates that the model is able to simulate the biogeochemical characteristics in Beibu Gulf.

Dark Septate Endophytic Fungi Help Tomato to Acquire Nutrients from Ground Plant Material

PubMed Central

Vergara, Carlos; Araujo, Karla E. C.; Urquiaga, Segundo; Schultz, Nivaldo; Balieiro, Fabiano de Carvalho; Medeiros, Peter S.; Santos, Leandro A.; Xavier, Gustavo R.; Zilli, Jerri E.

2017-01-01

Dark septate endophytic (DSE) fungi are facultative biotrophs that associate with hundreds of plant species, contributing to their growth. These fungi may therefore aid in the search for sustainable agricultural practices. However, several ecological functions of DSE fungi need further clarification. The present study investigated the effects of DSE fungi inoculation on nutrient recovery efficiency, nutrient accumulation, and growth of tomato plants fertilized with organic and inorganic N sources. Two experiments were carried out under greenhouse conditions in a randomized blocks design, with five replicates of tomato seedlings grown in pots filled with non-sterile sandy soil. Tomato seedlings (cv. Santa Clara I-5300) inoculated with DSE fungi (isolates A101, A104, and A105) and without DSE fungi (control) were transplanted to pots filled with 12 kg of soil which had previously received finely ground plant material [Canavalia ensiformis (L.)] that was shoot enriched with 0.7 atom % 15N (organic N source experiment) or ammonium sulfate-15N enriched with 1 atom % 15N (mineral N source experiment). Growth indicators, nutrient content, amount of nitrogen (N) in the plant derived from ammonium sulfate-15N or C. ensiformis-15N, and recovery efficiency of 15N, P, and K by plants were quantified 50 days after transplanting. The treatment inoculated with DSE fungi and supplied with an organic N source showed significantly higher recovery efficiency of 15N, P, and K. In addition, the 15N, N, P, K, Ca, Mg, Fe, Mn, and Zn content, plant height, leaf number, leaf area (only for the A104 inoculation), and shoot dry matter increased. In contrast, the only positive effects observed in the presence of an inorganic N source were fertilizer-K recovery efficiency, content of K, and leaf area when inoculated with the fungus A104. Inoculation with A101, A104, and A105 promoted the growth of tomato using organic N source (finely ground C. ensiformis-15N plant material). PMID:29312163

New insights into impacts of anthropogenic nutrients on urban ecosystem processes on the Southern California coastal shelf: Introduction and synthesis

NASA Astrophysics Data System (ADS)

Howard, Meredith D. A.; Kudela, Raphael M.; McLaughlin, Karen

2017-02-01

Anthropogenic nutrient inputs are one of the most important factors contributing to eutrophication of coastal waters. Coastal upwelling regions are naturally highly variable, exhibiting faster flushing and lower retention times than estuarine systems. As such, these regions are considered more resilient to anthropogenic influences than other coastal waters. Recent studies have shown our perception of the sustainability of these systems may be flawed and that anthropogenic nutrients can have an impact at local and regional spatial scales within these larger upwelling ecosystems. Maintenance of an outfall pipe discharging wastewater effluent to the Southern California Bight (SCB) provided an opportunity to study effects of anthropogenic nutrient inputs on a near-shore coastal ecosystem. The diversion of wastewater effluent from a primary, offshore outfall to a secondary, near-shore outfall set up a large-scale, in situ experiment allowing researchers to track the fate of wastewater plumes as they were "turned off" in one area and "turned on" in another. In this introduction to a special issue, we synthesize results of one such wastewater diversion conducted by the Orange County Sanitation District (OCSD) during fall 2012. Anthropogenic nitrogen (N) from point-source discharges altered biogeochemical cycling and the community composition of bacteria and phytoplankton. Nitrification of ammonium to nitrate in wastewater effluent close to outfalls constituted a significant source of N utilized by the biological community that should be considered in quantifying "new" production. The microbial-loop component of the plankton community played a significant role, exemplified by a large response of heterotrophic bacteria to wastewater effluent that resulted in nutrient immobilization within the bacterial food web. This response, combined with the photosynthetic inhibition of phytoplankton due to disinfection byproducts, suppressed phytoplankton responses. Our findings have ramifications for future studies and regulatory monitoring, emphasizing the need to consider chemical and biological responses to wastewater effluent in assessing effects of anthropogenic nutrient inputs on urbanized coastal ecosystems.

Trends in the nutrient enrichment of U.S. rivers during the late 20th century and their relation to changes in probable stream trophic conditions

USGS Publications Warehouse

Alexander, R.B.; Smith, R.A.

2006-01-01

We estimated trends in concentrations of total phosphorus (TP) and total nitrogen (TN) and the related change in the probabilities of trophic conditions from 1975 to 1994 at 250 nationally representative riverine monitoring locations in the U.S. with drainage areas larger than about 1,000 km2. Statistically significant (p < 0.05) declines were detected in TP and TN concentrations at 44% and 37% of the monitoring sites, and significant increases were detected at 3% and 9% of the sites, respectively. We used a statistical model to assess changes in the probable trophic-state classification of the sites after adjusting for climate-related variability in nutrient concentrations. The probabilistic assessment accounts for current knowledge of the trophic response of streams to nutrient enrichment, based on a recently proposed definition of "eutrophic," "mesotrophic," and "oligotrophic" conditions in relation to total nutrient concentrations. Based on these trophic definitions, we found that the trophic state improved at 25% of the monitoring sites and worsened at fewer than 5% of the sites; about 70% of the sites were unchanged. Improvements in trophic-state related to declines in TP were more common in predominantly forested and shrub-grassland watersheds, whereas the trophic state of predominantly agricultural sites was unchanged. Despite the declines in TP concentrations at many sites, about 50% of all monitoring sites, and more than 60% of the sites in predominantly agricultural and urban watersheds, were classified as eutrophic in 1994 based on TP concentrations. Contemporaneous reductions in major nutrient sources to streams, related to wastewater treatment upgrades, phosphate detergent bans, and declines in some agricultural sources, may have contributed to the declines in riverine nutrient concentrations and associated improvements in trophic conditions. ?? 2006, by the American Society of Limnology and Oceanography, Inc.

Research to Inform Nutrient Thresholds and Prioritization of Watersheds for Nutrient Management

EPA Science Inventory

The information in this presentation focuses on SSWR's 4.02 project, which will advance the science needed to inform decisions to prioritize watersheds and nutrient sources for nutrient management and define appropriate nutrient levels for the nation’s waters, two importan...

Water-quality assessment of the Albemarle-Pamlico drainage basin, North Carolina and Virginia; characterization of suspended sediment, nutrients, and pesticides

USGS Publications Warehouse

Harned, Douglas; McMahon, Gerard; Spruill, T.B.; Woodside, M.D.

1995-01-01

The 28,000-square-mile Albemarle-Pamlico drainage basin includes the Roanoke, Dan, Chowan Tar, and Neuse Rivers. The basin extends through four physiographic provinces in North Carolina and Virginia-Valley and Ridge, Blue Ridge, Piedmont and Coastal Plain. The spatial and temporal trends in ground-water and riverine water quality in the study area were characterized by using readily available data sources The primary data sources that were used included the U.S. Geological Survey's National Water Data Storage and Retrieval System (WATSTORE) database, the U.S. Environmental Protection Agency's Storage and Retrieval System (STORET) database, and results of a few investigations of pesticide occurrence. The principal water-quality constituents examined were suspended sediment, nutrients, and pesticides. The data examined generally spanned the period from 1950 to 1993. The only significant trends in suspended sediment were detected at three Chowan River tributary sites which showed long-term decreases. Suspended- and total-solids concentrations have decreased throughout the Albemarle-Pamlico drainage basin. The decreases are probably a result of (1) construction of new lakes and ponds in the basin, which trap solids, (2) improved agricultural soil management, and (3) improved wastewater treatment. Nutrient point sources are much less than nonpoint nutrient sources at the eight NASQAN basins examined for nutrient loads. The greatest nitrogen inputs are associated with crop fertilizer and biological nitrogen fixation by soybeans and peanuts, whereas atmospheric and animal-related nitrogen inputs are comparable in magnitude. The largest phosphorus inputs are associated with animal wastes. The most commonly detected pesticides in surface water in the STORET database were atrazine and aldrin.Intensive organonitrogen herbicide sampling of Chicod Creek in 1992 showed seasonal variations in pesticide concentration. The most commonly detected herbicides were atrazine, alachlor, metolachlor, prometon, and metribuzin. No relation between streamflow and pesticide concentration was evident.

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.

Soil nutrient availability and reproductive effort drive patterns in nutrient resorption in Pentachlethra macroloba

Treesearch

K. L. Tully; Tana Wood; A. M. Schwantes; D. Lawrence

2013-01-01

The removal of nutrients from senescing tissues, nutrient resorption, is a key strategy for conserving nutrients in plants. However, our understanding of what drives patterns of nutrient resorption in tropical trees is limited. We examined the effects of nutrient sources (stand-level and tree-level soil fertility) and sinks (reproductive effort) on nitrogen (N) and...

What's Upstream? GIS's critical role in developing nutrient ...

EPA Pesticide Factsheets

Eutrophication due to excess levels of nitrogen and phosphorus can seriously impair ecological function in estuaries. Protective criteria for nutrients are difficult to establish because the source can vary spatially and seasonally, originate either from the watershed or the ocean, and be natural or anthropogenic. GIS tools and processes can help in developing nutrient criteria by establishing reference conditions representative of natural background nutrient levels. Along the Oregon Coast in the Pacific Northwest, the primary source of nutrients in the wet season (November-April) is generally riverine. We delineated and extracted explicit spatial data from watersheds upstream of riverine water quality monitoring stations for parametric comparison to recorded nutrient levels. The SPARROW model (Wise and Johnson, 2011) was used to estimate relative contributions of nutrient sources at each station. Both raster and vector spatial data were used and include land use / land cover, demography, geology, terrain, precipitation and forest type. The relationships of nutrients to spatial data were then explored as an approach to establishing the reference expectation. The abstract introduces Geographic Information Systems (GIS) tools and processes employed for research conducted under the Safe and Sustainable Water Resources (SSWR) Task 2.3A, entitled “Nutrient Management for Sustainability of Aquatic Ecosystems.” One of the goals of the EPA Office of Water is to

Utilization of the water soluable fraction of wheat straw as a plant nutrient source

NASA Technical Reports Server (NTRS)

Mackowiak, C. L.; Garland, J. L.

1990-01-01

Recovery of water soluble, inorganic nutrients from the inedible portion of wheat was found to be an effective means of recycling nutrients within hydroponic systems. Through aqueous extraction (leaching), 60 percent of the total inorganic nutrient weight was removed from wheat straw and roots, although the recovery of individual nutrients varied. Leaching also removed about 20 percent of the total organic carbon from the biomass. In terms of dry weight, the leachate was comprised of approximately 60 percent organic and 40 percent inorganic compounds. Direct use of wheat straw leachate in static hydroponic systems had an inhibitory effect on wheat growth, both in the presence and absence of microorganisms. Biological treatment of leachate either with a mixed microbial community or the oyster mushroom Pleurotus ostreatus L., prior to use in hydroponic solutions, significantly reduced both the organic content and the inhibitory effects of the leachate. The inhibitory effects of unprocessed leachate appear to be a result of rapidly acting phytotoxic compounds that are detoxified by microbial activity. Leaching holds considerable promise as a method for nutrient recycling in a Controlled Ecological Life Support System (CELSS).

Sources of nitrogen and phosphorus emissions to Irish rivers: estimates from the Source Load Apportionment Model (SLAM)

NASA Astrophysics Data System (ADS)

Mockler, Eva; Deakin, Jenny; Archbold, Marie; Daly, Donal; Bruen, Michael

2017-04-01

More than half of the river and lake water bodies in Europe are at less than good ecological status or potential, and diffuse pollution from agriculture remains a major, but not the only, cause of this poor performance. In Ireland, it is evident that agri-environmental policy and land management practices have, in many areas, reduced nutrient emissions to water, mitigating the potential impact on water quality. However, additional measures may be required in order to further decouple the relationship between agricultural productivity and emissions to water, which is of vital importance given the on-going agricultural intensification in Ireland. Catchment management can be greatly supported by modelling, which can reduce the resources required to analyse large amounts of information and can enable investigations and measures to be targeted. The Source Load Apportionment Model (SLAM) framework was developed to support catchment management in Ireland by characterising the contributions from various sources of phosphorus (P) and nitrogen (N) emissions to water. The SLAM integrates multiple national spatial datasets relating to nutrient emissions to surface water, including land use and physical characteristics of the sub-catchments to predict emissions from point (wastewater, industry discharges and septic tank systems) and diffuse sources (agriculture, forestry, peatlands, etc.). The annual nutrient emissions predicted by the SLAM were assessed against nutrient monitoring data for 16 major river catchments covering 50% of the area of Ireland. At national scale, results indicate that the total average annual emissions to surface water in Ireland are over 2,700 t yr-1 of P and 80,000 t yr-1 of N. The SLAM results include the proportional contributions from individual sources at a range of scales from sub-catchment to national, and show that the main sources of P are from wastewater and agriculture, with wide variations across the country related to local anthropogenic pressures and the hydrogeological setting. Agriculture is the main source of N emissions to water across all regions of Ireland. The SLAM results have been incorporated into an Integrated Catchment Management process and used in conjunction with monitoring data and local knowledge during the characterisation of all Irish water bodies by the Environmental Protection Agency. This demonstrates the successful integration of research into catchment management to inform the identification of (i) the sources of nutrients at regional and local scales and (ii) the potential significant pressures and appropriate mitigation measures.

Mucin acts as a nutrient source and a signal for the differential expression of genes coding for cellular processes and virulence factors in Acinetobacter baumannii

PubMed Central

Ohneck, Emily J.; Arivett, Brock A.; Fiester, Steven E.; Wood, Cecily R.; Metz, Maeva L.; Simeone, Gabriella M.

2018-01-01

The capacity of Acinetobacter baumannii to persist and cause infections depends on its interaction with abiotic and biotic surfaces, including those found on medical devices and host mucosal surfaces. However, the extracellular stimuli affecting these interactions are poorly understood. Based on our previous observations, we hypothesized that mucin, a glycoprotein secreted by lung epithelial cells, particularly during respiratory infections, significantly alters A. baumannii’s physiology and its interaction with the surrounding environment. Biofilm, virulence and growth assays showed that mucin enhances the interaction of A. baumannii ATCC 19606T with abiotic and biotic surfaces and its cytolytic activity against epithelial cells while serving as a nutrient source. The global effect of mucin on the physiology and virulence of this pathogen is supported by RNA-Seq data showing that its presence in a low nutrient medium results in the differential transcription of 427 predicted protein-coding genes. The reduced expression of ion acquisition genes and the increased transcription of genes coding for energy production together with the detection of mucin degradation indicate that this host glycoprotein is a nutrient source. The increased expression of genes coding for adherence and biofilm biogenesis on abiotic and biotic surfaces, the degradation of phenylacetic acid and the production of an active type VI secretion system further supports the role mucin plays in virulence. Taken together, our observations indicate that A. baumannii recognizes mucin as an environmental signal, which triggers a response cascade that allows this pathogen to acquire critical nutrients and promotes host-pathogen interactions that play a role in the pathogenesis of bacterial infections. PMID:29309434

Nitrogen enrichment and speciation in a coral reef lagoon driven by groundwater inputs of bird guano

NASA Astrophysics Data System (ADS)

McMahon, Ashly; Santos, Isaac R.

2017-09-01

While the influence of river inputs on coral reef biogeochemistry has been investigated, there is limited information on nutrient fluxes related to submarine groundwater discharge (SGD). Here, we investigate whether significant saline groundwater-derived nutrient inputs from bird guano drive coral reef photosynthesis and calcification off Heron Island (Great Barrier Reef, Australia). We used multiple experimental approaches including groundwater sampling, beach face transects, and detailed time series observations to assess the dynamics and speciation of groundwater nutrients as they travel across the island and discharge into the coral reef lagoon. Nitrogen speciation shifted from nitrate-dominated groundwater (>90% of total dissolved nitrogen) to a coral reef lagoon dominated by dissolved organic nitrogen (DON; ˜86%). There was a minimum input of nitrate of 2.1 mmol m-2 d-1 into the lagoon from tidally driven submarine groundwater discharge estimated from a radon mass balance model. An independent approach based on the enrichment of dissolved nutrients during isolation at low tide implied nitrate fluxes of 5.4 mmol m-2 d-1. A correlation was observed between nitrate and daytime net ecosystem production and calcification. We suggest that groundwater nutrients derived from bird guano may offer a significant addition to oligotrophic coral reef lagoons and fuel ecosystem productivity and the coastal carbon cycle near Heron Island. The large input of groundwater nutrients in Heron Island may serve as a natural ecological analogue to other coral reefs subject to large nutrient inputs from anthropogenic sources.

A GIS-based Upscaling Estimation of Nutrient Runoff Losses from Rice Paddy Fields to a Regional Level.

PubMed

Sun, Xiaoxiao; Liang, Xinqiang; Zhang, Feng; Fu, Chaodong

2016-11-01

Nutrient runoff losses from cropping fields can lead to nonpoint source pollution; however, the level of nutrient export is difficult to evaluate, particularly at the regional scale. This study aimed to establish a novel yet simple approach for estimating total nitrogen (TN) and total phosphorus (TP) runoff losses from regional paddy fields. In this approach, temporal changes of nutrient concentrations in floodwater were coupled with runoff-processing functions in rice ( L.) fields to calculate nutrient runoff losses for three site-specific field experiments. Validation experiments verified the accuracy of this method. The geographic information system technique was used to upscale and visualize the TN and TP runoff losses from field to regional scales. The results indicated that nutrient runoff losses had significant spatio-temporal variation characteristics during rice seasons, which were positively related to fertilizer rate and precipitation. The average runoff losses over five study seasons were 20.21 kg N ha for TN and 0.76 kg P ha for TP. Scenario analysis showed that TN and TP losses dropped by 7.64 and 3.0%, respectively, for each 10% reduction of fertilizer input. For alternate wetting and drying water management, the corresponding reduction ratio was 24.7 and 14.0% respectively. Our results suggest that, although both water and fertilizer management can mitigate nutrient runoff losses, the former is significantly more effective. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

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.

Cross-shelf transport of sub-thermocline nitrate by the internal tide and rapid (3-6 h) incorporation by an inshore macroalga

NASA Astrophysics Data System (ADS)

Ladah, Lydia B.; Filonov, Anatoliy; Lavín, Miguel F.; Leichter, James J.; Zertuche-González, José A.; Pérez-Mayorga, Diana M.

2012-07-01

During summer in shallow waters off Baja California, Mexico, the internal tide is a dominant thermal feature of the water column. However, its importance for sub-thermocline nutrient provision to benthic macroalgae is unknown. In order to determine if internal motions provide nutrients to macroalgae in summer, Ulva lactuca was outplanted at inshore stations for short (3 and 6 h) intervals, at the surface, 5 and 10 m depth, and tissue nitrogen content was measured before and after each deployment. Concurrently temperature, currents, and nutrients were measured using moored thermistors, current profilers, CTDs, Niskin bottles, and an in-situ UV absorbance nitrate sensor (ISUS). Discrete pulses of cool, nutrient-rich water were horizontally displaced at least 4 km on the shelf and shoaled more than 20 m depth at the semidiurnal frequency, resulting in more than a 10-fold change in the concentration of nitrate. Inshore, tissue nitrogen of Ulva outplants increased significantly during longer exposures to this cool water. At this site, the semidiurnal signal dominates water column temperature fluctuations from April to November, with summer showing the greatest cooling (up to 5 °C) in a one-hour period. We estimated that 11% of the days of a year show internal waves that would cause a significant change in nutrient availability to macroalgae at 5 m depth. This study supports the hypothesis that nitrate can reach and be rapidly incorporated by inshore macroalgae such as Ulva through transport forced by the internal tide, and that even very short (<1 h) nutrient pulses in nature are reflected in macroalgal tissue. We propose that at this site, the internal tide provides a significant, yet understudied, high frequency nutrient source to inshore primary producers, particularly in summer.

Regional assessments of the Nation's water quality—Improved understanding of stream nutrient sources through enhanced modeling capabilities

USGS Publications Warehouse

Preston, Stephen D.; Alexander, Richard B.; Woodside, Michael D.

2011-01-01

The U.S. Geological Survey (USGS) recently completed assessments of stream nutrients in six major regions extending over much of the conterminous United States. SPARROW (SPAtially Referenced Regressions On Watershed attributes) models were developed for each region to explain spatial patterns in monitored stream nutrient loads in relation to human activities and natural resources and processes. The model information, reported by stream reach and catchment, provides contrasting views of the spatial patterns of nutrient source contributions, including those from urban (wastewater effluent and diffuse runoff from developed land), agricultural (farm fertilizers and animal manure), and specific background sources (atmospheric nitrogen deposition, soil phosphorus, forest nitrogen fixation, and channel erosion).

Nutrient sensing modulates malaria parasite virulence

PubMed Central

Mancio-Silva, Liliana; Slavic, Ksenija; Grilo Ruivo, Margarida T.; Grosso, Ana Rita; Modrzynska, Katarzyna K.; Vera, Iset Medina; Sales-Dias, Joana; Gomes, Ana Rita; MacPherson, Cameron Ross; Crozet, Pierre; Adamo, Mattia; Baena-Gonzalez, Elena; Tewari, Rita; Llinás, Manuel; Billker, Oliver; Mota, Maria M.

2017-01-01

The lifestyle of intracellular pathogens, such as malaria parasites, is intimately connected to that of their host(s), primarily for nutrient supply. Nutrients act not only as primary sources of energy but also as regulators of gene expression, metabolism and growth, through various signaling networks that confer to cells the ability to sense and adapt to varying environmental conditions1,2. Canonical nutrient-sensing pathways are presumably absent in the causing agent of malaria Plasmodium3–5, thus raising the question of whether these parasites possess the capacity to sense and cope with host nutrient fluctuations. Here, we show that Plasmodium blood-stage parasites actively respond to host dietary calorie alterations through a rearrangement of their transcriptome accompanied by a significant adjustment of their multiplication rate. A kinome analysis combined with chemical and genetic approaches identified KIN as a critical regulator that mediates sensing of nutrients and controls a transcriptional response to the host nutritional status. KIN shares homology to SNF1/AMPKα and yeast complementation studies suggest functional conservation of an ancient cellular energy sensing pathway. Overall, these findings reveal a key parasite nutrient-sensing mechanism that is critical to modulate parasite replication and virulence. PMID:28678779

NutrientNet: An Internet-Based Approach to Teaching Market-Based Policy for Environmental Management

ERIC Educational Resources Information Center

Nguyen, To N.; Woodward, Richard T.

2009-01-01

NutrientNet is an Internet-based environment in which a class can simulate a market-based approach for improving water quality. In NutrientNet, each student receives a role as either a point source or a nonpoint source polluter, and then the participants are allowed to trade water quality credits to cost-effectively reduce pollution in a…

Soil nutrients, bacteria populations, and veterinary pharmaceuticals across a backgrounding beef feedlot

USDA-ARS?s Scientific Manuscript database

Beef cattle backgrounding feedlot systems that grow out weaned calves for feedlot finishing can become potential diffuse sources of environmentally significant contaminants. Better understanding of these contaminants and their distribution will aid in development of effective contaminant management...

Effect of phosphorous concentrations on sedimentary distributions and isotopic composition of algal lipid biomarkers in lakes from central Switzerland

NASA Astrophysics Data System (ADS)

Ladd, N.; Dubois, N.; Schubert, C. J.

2015-12-01

Lakes in the Swiss central plateau experienced increasing anthropogenic phosphorous loading throughout much of the 20th century. Since the 1980s concerted remediation efforts on the part of the Swiss government have significantly reduced P concentrations in most lakes and reversed previous eutrophication. However, P concentrations remain elevated above their preindustrial levels in many sites. High quality monitoring of lake nutrient levels since the 1950s, along with several lakes of wide-ranging P concentrations in close proximity, make central Switzerland an ideal location for studying the ways in which nutrient loading affects the organic composition of lacustrine sediments. Results of such studies can be used to develop proxies of eutrophication in sites where fewer historical data exist, and to reconstruct historical P concentrations in local lakes from the time before record keeping began. We analyzed the distributions of algal lipid biomarkers from surface sediment and sediment traps collected in the spring of 2015 from ten lakes with variable P concentrations in central Switzerland. Sedimentary lipid distributions from these lakes confirm that biomarkers associated with algal and cyanobacterial sources are more abundant in the sediment of lakes with greater P loading. The dry sedimentary concentrations of biomarkers such as brassicasterol (primarily diatom source) and diplopterol (cyanobacteria source), as well as the less source specific short-chain n-alkanols, linearly increase from 0.3 - 1.9 μg/g as total phosphorous in the upper water column increases by 1 μg/L over a range of 7 - 50 μg/L. We also present preliminary hydrogen isotope data from these biomarkers. Hydrogen isotopes of algal lipids primarily reflect the source water in which the algae grew, and this relationship has been developed as a paleohydrologic proxy. However, laboratory cultures of marine algae demonstrate that they discriminate more against 2H under nutrient replete conditions. We present the first field assessment of how nutrient availability influences 2H fractionation in freshwater algae, and demonstrate how such measurements can be used to infer past information about anthropogenic nutrient loading.

Contamination of organic nutrient sources with potentially toxic elements, antibiotics and pathogen microorganisms in relation to P fertilizer potential and treatment options for the production of sustainable fertilizers: A review.

PubMed

Bloem, E; Albihn, A; Elving, J; Hermann, L; Lehmann, L; Sarvi, M; Schaaf, T; Schick, J; Turtola, E; Ylivainio, K

2017-12-31

Organic nutrient sources such as farmyard manure, sewage sludge, their biogas digestates or other animal by-products can be valuable fertilizers delivering organic matter to the soil. Currently, especially phosphorus (P) is in the focus of research since it is an essential plant nutrient with finite resources, estimated to last only for some more decades. Efficient utilization of organic P sources in agriculture will help to preserve P resources and thereby has the potential to close nutrient cycles and prevent unwanted P-losses to the environment, one of the major causes for eutrophication of water bodies. Unfortunately, organic P sources usually contain also various detrimental substances, such as potentially toxic elements or organic contaminants like pharmaceuticals as well as pathogenic microorganisms. Additionally, the utilization of some of these substrates such as sewage sludge or animal by-products is legally limited in agriculture because of the potential risk to contaminate sites with potentially toxic elements and organic contaminants. Thus, to close nutrient cycles it is important to develop solutions for the responsible use of organic nutrient sources. The aim of this review is to give an overview of the contamination of the most important organic nutrient sources with potentially toxic elements, antibiotics (as one important organic contaminant) and pathogenic microorganisms. Changes in manure and sewage sludge management as well as the increasing trend to use such substrates in biogas plants will be discussed with respect to potential risks posed to soils and water bodies. Some examples for abatement options by which contamination can be reduced to produce P fertilizers with high amounts of plant available P forms are presented. Copyright © 2017 Elsevier B.V. All rights reserved.

Interacting Physical and Biological Processes Affecting Nutrient Transport Through Human Dominated Landscapes

NASA Astrophysics Data System (ADS)

Finlay, J. C.

2015-12-01

Human activities increasingly dominate biogeochemical cycles of limiting nutrients on Earth. Urban and agricultural landscapes represent the largest sources of excess nutrients that drive water quality degradation. The physical structure of both urban and agricultural watersheds has been extensively modified, and these changes have large impacts on water and nutrient transport. Despite strong physical controls over nutrient transport in human dominated landscapes, biological processes play important roles in determining the fates of both nitrogen and phosphorus. This talk uses examples from research in urban and agricultural watersheds in the Midwestern USA to illustrate interactions of physical and biological controls over nutrient cycles that have shifted nitrogen (N) and phosphorus (P) sources and cycling in unexpected ways in response to management changes. In urban watersheds, efforts to improve water quality have been hindered by legacy sources of phosphorus added to storm water through transport to drainage systems by vegetation. Similarly, reductions in field erosion in agricultural watersheds have not led to major reductions in phosphorus transport, because of continued release of biological sources of P. Where management of phosphorus has been most effective in reducing eutrophication of lakes, decreases in N removal processes have led to long term increases in N concentration and transport. Together, these examples show important roles for biological processes affecting nutrient movement in highly modified landscapes. Consideration of the downstream physical and biological responses of management changes are thus critical toward identification of actions that will most effectively reduce excess nutrients watersheds and coastal zones.

Stream restoration and sewers impact sources and fluxes of water,carbon, and nutrients in urban watersheds

EPA Science Inventory

An improved understanding of sources and timing of water and nutrient fluxes associated with urban stream restoration is critical for guiding effective watershed management. We investigated how sources, fluxes, and flowpaths of water, carbon (C), nitrogen (N), and phosphorus (P)...

Combination of plant and insect eggs as food sources facilitates ovarian development in an omnivorous bug Apolygus lucorum (Hemiptera: Miridae).

PubMed

Yuan, Wei; Li, Wenjing; Li, Yunhe; Wu, Kongming G

2013-06-01

Diet nutrient is considered as an important regulatory factor for reproduction of insects. To understand the effect of different food sources on the reproductive physiology of Apolygus lucorum (Meyer-Dür), the ovarian development in adult females was investigated when they were fed on green beans (Gb), combination of green beans Phaseolus vulgaris L and Helicoverpa armigera eggs (GbHe), or H. armigera eggs (He). A female of A. lucorum has two ovaries, and each ovary contained seven yellowish ovarioles. Females fed on Gb or GbHe had larger ovaries and the ovarioles contained larger numbers of oocytes compared with those fed on He. Females in GeHe treatment has significantly higher number of follicles per ovary throughout the whole adult period compared with those in Gb or He treatment. Furthermore, the length of the best developed ovariole was affected by the diet type. The females fed on GbHe had the most developed ovarioles, with significantly longer ovarioles than those fed on Gb or He. A method was described to quantitatively score the degree of ovarian development in the current study. Similarly, the ovarian development scores were significantly higher for females in GbHe treatment than those in other two diet treatments. The ovarian development significantly delayed for females fed on He. Our results demonstrate that A. lucorum, as an omnivorous insect species, can acquire nutrients from both plant and animal origin food sources, and the combination of plants and animal food sources can significantly facilitate the ovary development of its females.

Scale and legacy controls on catchment nutrient export regimes

NASA Astrophysics Data System (ADS)

Howden, N. J. K.; Burt, T.; Worrall, F.

2017-12-01

Nutrient dynamics in river catchments are complex: water and chemical fluxes are highly variable in low-order streams, but this variability declines as fluxes move through higher-order reaches. This poses a major challenge for process understanding as much effort is focussed on long-term monitoring of the main river channel (a high-order reach), and therefore the data available to support process understanding are predominantly derived from sites where much of the transient response of nutrient export is masked by the effect of averaging over both space and time. This may be further exacerbated at all scales by the accumulation of legacy nutrient sources in soils, aquifers and pore waters, where historical activities have led to nutrient accumulation where the catchment system is transport limited. Therefore it is of particular interest to investigate how the variability of nutrient export changes both with catchment scale (from low to high-order catchment streams) and with the presence of legacy sources, such that the context of infrequent monitoring on high-order streams can be better understood. This is not only a question of characterising nutrient export regimes per se, but also developing a more thorough understanding of how the concepts of scale and legacy may modify the statistical characteristics of observed responses across scales in both space and time. In this paper, we use synthetic data series and develop a model approach to consider how space and timescales combine with impacts of legacy sources to influence observed variability in catchment export. We find that: increasing space and timescales tend to reduce the observed variance in nutrient exports, due to an increase in travel times and greater mixing, and therefore averaging, of sources; increasing the influence of legacy sources inflates the variance, with the level of inflation dictated by the residence time of the respective sources.

Are edible insects more or less 'healthy' than commonly consumed meats? A comparison using two nutrient profiling models developed to combat over- and undernutrition.

PubMed

Payne, C L R; Scarborough, P; Rayner, M; Nonaka, K

2016-03-01

Insects have been the subject of recent attention as a potentially environmentally sustainable and nutritious alternative to traditional protein sources. The purpose of this paper is to test the hypothesis that insects are nutritionally preferable to meat, using two evaluative tools that are designed to combat over- and under-nutrition. We selected 183 datalines of publicly available data on the nutrient composition of raw cuts and offal of three commonly consumed meats (beef, pork and chicken), and six commercially available insect species, for energy and 12 relevant nutrients. We applied two nutrient profiling tools to this data: The Ofcom model, which is used in the United Kingdom, and the Nutrient Value Score (NVS), which has been used in East Africa. We compared the median nutrient profile scores of different insect species and meat types using non-parametric tests and applied Bonferroni adjustments to assess for statistical significance in differences. Insect nutritional composition showed high diversity between species. According to the Ofcom model, no insects were significantly 'healthier' than meat products. The NVS assigned crickets, palm weevil larvae and mealworm a significantly healthier score than beef (P<0.001) and chicken (P<0.001). No insects were statistically less healthy than meat. Insect nutritional composition is highly diverse in comparison with commonly consumed meats. The food category 'insects' contains some foods that could potentially exacerbate diet-related public health problems related to over-nutrition, but may be effective in combating under-nutrition.

Examining diapirs as a nutrient source for plants in a High Arctic polar desert.

NASA Astrophysics Data System (ADS)

Hardy, Sarah; Siciliano, Steven

2014-05-01

Polar deserts cover a quarter of ice-free land in the Canadian Arctic, yet little is known about the key ecological processes that take place. This understudied ecosystem is becoming increasingly vulnerable to climate change and growth of the natural resource industry. In polar deserts, below ground soil masses called diapirs occur in some patterned ground features such as frost boils. Diapirs are formed above permafrost soil where increases in moisture and temperature stimulate biological activity when thawing occurs to create an organic rich, Bhy horizon. Vascular plants are scarce (< 5% cover) and nutrients for survival are likely supplied by diapirs but this interaction is poorly understood. To determine if diapirs are an important nutrient source, nitrogen and phosphorous were traced from the diapir Bhy to vascular plants using δ15N and δ18O stable isotope signatures. Recent developments have shown that the oxygen isotopes of orthophosphate (18OP) can be used to trace plant-available phosphorous. At a polar desert site at Alexandra Fjord, Canada, diapir (n=12) and non-diapir (n=12) frost boils were identified in 12 blocks with a field-portable vis-NIR (visible and near infrared spectrometer) device. Soil cores and Salix arctica plant tissue were collected from each frost boil for stable isotope analysis. The δ15N of Salix arctica plant tissue (n=144) shows a significant relationship between block location and diapir presence (p=0.003). There was a consistent pattern in average δ15N in plant tissue parts with increasing concentration from leaf, stem to root in all frost boils. There was no significant difference in total plant δ15N between diapir and non-diapir frost boils but δ15N in soil cores will be measured to determine if these signatures are attributed to the Bhy horizon or biological nitrogen fixation. These results highlight the potential for stable isotopes to be used as a nutrient tracer in polar desert ecosystems and further analysis of phosphorous stable isotopes will provide a clearer picture of the role of diapirs as a nutrient source.

Food Sources of Energy and Nutrients in Infants, Toddlers, and Young Children from the Mexican National Health and Nutrition Survey 2012

PubMed Central

Denney, Liya; Afeiche, Myriam C.; Eldridge, Alison L.; Villalpando-Carrión, Salvador

2017-01-01

Food sources of nutrients in Mexican children are not well known. To fill the knowledge gap, dietary intake was assessed in 2057 children using a 24-h dietary recall. All reported foods and beverages were assigned to one of 76 food groups. Percent contribution of each food group to nutrient intake was estimated for four age groups: 0–5.9, 6–11.9, 12–23.9, and 24–47.9 months. Breast milk, infant formula, and cow’s milk were the top sources of energy and nutrients, especially in younger groups. Among infants aged 6–11.9 months, the top food sources of energy included soups and stews, cookies, fruit, tortillas, eggs and egg dishes, and traditional beverages. The same foods plus sweetened breads, dried beans, and sandwiches and tortas were consumed as the top sources of energy among toddlers and young children. Milk, soups, and stews were the top contributors for all nutrients and tortillas, eggs, and egg dishes were among the top contributors for iron and zinc. This study showed that low nutrient-dense cookies, sweetened breads, and traditional beverages were among the core foods consumed early in life in Mexico. This compromises the intake of more nutritious foods such as vegetables and fortified cereals and increases the risk of obesity. PMID:28505084

Food Sources of Energy and Nutrients in Infants, Toddlers, and Young Children from the Mexican National Health and Nutrition Survey 2012.

PubMed

Denney, Liya; Afeiche, Myriam C; Eldridge, Alison L; Villalpando-Carrión, Salvador

2017-05-13

Food sources of nutrients in Mexican children are not well known. To fill the knowledge gap, dietary intake was assessed in 2057 children using a 24-hour dietary recall. All reported foods and beverages were assigned to one of 76 food groups. Percent contribution of each food group to nutrient intake was estimated for four age groups: 0-5.9, 6-11.9, 12-23.9, and 24-47.9 months. Breast milk, infant formula, and cow's milk were the top sources of energy and nutrients, especially in younger groups. Among infants aged 6-11.9 months, the top food sources of energy included soups and stews, cookies, fruit, tortillas, eggs and egg dishes, and traditional beverages. The same foods plus sweetened breads, dried beans, and sandwiches and tortas were consumed as the top sources of energy among toddlers and young children. Milk, soups, and stews were the top contributors for all nutrients and tortillas, eggs, and egg dishes were among the top contributors for iron and zinc. This study showed that low nutrient-dense cookies, sweetened breads, and traditional beverages were among the core foods consumed early in life in Mexico. This compromises the intake of more nutritious foods such as vegetables and fortified cereals and increases the risk of obesity.

Biomass burning: A significant source of nutrients for Andean rainforests

NASA Astrophysics Data System (ADS)

Fabian, P. F.; Rollenbeck, R.; University Of Marburg, Germany

2010-12-01

Regular rain and fogwater sampling in the Podocarpus National Park,on the humid eastern slopes of the Ecuadorian Andes,has been carried out since 2002.The samples,accumulated over about 1-week intervals,were analysed for pH,conductivity,and major ions (K+, Na+, NH4+, Ca2+, Mg2+, Cl-, SO4 2-, NO3-, PO4 3- ).Annual deposition rates of these ions which, due to poor acidic soils with low mineralization rates,constitute the dominant nutrient supply to the mountaineous rainforests, and major ion sources could be determined using back trajectories,along with satellite data. While most of the Na, Cl, and K as well as Ca and Mg input was found to originate from natural oceanic and desert dust sources,respectively (P.Fabian et al.,Adv.Geosci.22,85-94, 2009), NO3, NH4, and about 90% of SO4 (about 10 % is from active volcanoes) are almost entirely due to anthropogenic sources,most likely biomass burning. Industrial and transportation emissions and other pollutants,however,act in a similar way as the precursors produced by biomass burning.For quantifying the impacts of biomass burning vs. those of anthropogenic sources other than biomass burning we used recently established emission inventories,along with simplified model calculations on back trajectories.First results yielding significant contributions of biomass burning will be discussed.

New England SPARROW Water-Quality Modeling to Assist with the Development of Total Maximum Daily Loads in the Connecticut River Basin

NASA Astrophysics Data System (ADS)

Moore, R. B.; Robinson, K. W.; Simcox, A. C.; Johnston, C. M.

2002-05-01

The U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency (USEPA) and the New England Interstate Water Pollution Control Commission (NEWIPCC), is currently preparing a water-quality model, called SPARROW, to assist in the regional total maximum daily load (TMDL) studies in New England. A model is required to provide estimates of nutrient loads and confidence intervals at unmonitored stream reaches. SPARROW (Spatially Referenced Regressions on Watershed Attributes) is a spatially detailed, statistical model that uses regression equations to relate total phosphorus and nitrogen (nutrient) stream loads to pollution sources and watershed characteristics. These statistical relations are then used to predict nutrient loads in unmonitored streams. The New England SPARROW model is based on a hydrologic network of 42,000 stream reaches and associated watersheds. Point source data are derived from USEPA's Permit Compliance System (PCS). Information about nonpoint sources is derived from data such as fertilizer use, livestock wastes, and atmospheric deposition. Watershed characteristics include land use, streamflow, time-of-travel, stream density, percent wetlands, slope of the land surface, and soil permeability. Preliminary SPARROW results are expected in Spring 2002. The New England SPARROW model is proposed for use in the TMDL determination for nutrients in the Connecticut River Basin, upstream of Connecticut. The model will be used to estimate nitrogen loads from each of the upstream states to Long Island Sound. It will provide estimates and confidence intervals of phosphorus and nitrogen loads, area-weighted yields of nutrients by watershed, sources of nutrients, and the downstream movement of nutrients. This information will be used to (1) understand ranges in nutrient levels in surface waters, (2) identify the environmental factors that affect nutrient levels in streams, (3) evaluate monitoring efforts for better determination of nutrient loads, and (4) evaluate management options for reducing nutrient loads to achieve water-quality goals.

Global Modeling Study of the Bioavailable Atmospheric Iron Supply to the Global Ocean

NASA Astrophysics Data System (ADS)

Myriokefalitakis, S.; Krol, M. C.; van Noije, T.; Le Sager, P.

2017-12-01

Atmospheric deposition of trace constituents acts as a nutrient source to the open ocean and affect marine ecosystem. Dust is known as a major source of nutrients to the global ocean, but only a fraction of these nutrients is released in a bioavailable form that can be assimilated by the marine biota. Iron (Fe) is a key micronutrient that significantly modulates gross primary production in the High-Nutrient-Low-Chlorophyll (HNLC) oceans, where macronutrients like nitrate are abundant, but primary production is limited by Fe scarcity. The global atmospheric Fe cycle is here parameterized in the state-of-the-art global Earth System Model EC-Earth. The model takes into account the primary emissions of both insoluble and soluble Fe forms, associated with mineral dust and combustion aerosols. The impact of atmospheric acidity and organic ligands on mineral dissolution processes, is parameterized based on updated experimental and theoretical findings. Model results are also evaluated against available observations. Overall, the link between the labile Fe atmospheric deposition and atmospheric composition changes is here demonstrated and quantified. This work has been financed by the Marie-Curie H2020-MSCA-IF-2015 grant (ID 705652) ODEON (Online DEposition over OceaNs; modeling the effect of air pollution on ocean bio-geochemistry in an Earth System Model).

Medical Hydrogeology of Asian Deltas: Status of Groundwater Toxicants and Nutrients, and Implications for Human Health

PubMed Central

Hoque, Mohammad A.; Butler, Adrian P.

2015-01-01

Drinking water, a fluid primarily for human hydration, is also a source of mineral nutrients. Groundwater, a drinking water source for more than 70% of inhabitants living in Asian deltas, has received much attention because of its naturally occurring arsenic, but the linkage of arsenic toxicity with other water constituents has not been studied. In addition, although nutrients are generally provided by food, in under developed rural settings, where people subsist on low nutrient diets, drinking-water-nutrients may supply quantities vital to human health thereby preventing diseases. Here, we show, using augmented datasets from three Asian deltas (Bengal, Mekong, and Red River), that the chemical content of groundwater is such that in some areas individuals obtain up to 50% or more of the recommended daily intake (RDI) of some nutrients (e.g., calcium, magnesium, iron) from just two litres of drinking water. We also show some indications of a spatial association of groundwater nutrients and health outcome using demographic health data from Bangladesh. We therefore suggest that an understanding of the association of non-communicable disease and poor nutrition cannot be developed, particularly in areas with high levels of dissolved solids in water sources, without considering the contribution of drinking water to nutrient and mineral supply. PMID:26712780

The stocks and flows of nitrogen, phosphorus and potassium across a 30-year time series for agriculture in Huantai county, China.

PubMed

Bellarby, Jessica; Surridge, Ben W J; Haygarth, Philip M; Liu, Kun; Siciliano, Giuseppina; Smith, Laurence; Rahn, Clive; Meng, Fanqiao

2018-04-01

In order to improve the efficiency of nutrient use whilst also meeting projected changes in the demand for food within China, new nutrient management frameworks comprised of policy, practice and the means of delivering change are required. These frameworks should be underpinned by systemic analyses of the stocks and flows of nutrients within agricultural production. In this paper, a 30-year time series of the stocks and flows of nitrogen (N), phosphorus (P) and potassium (K) are reported for Huantai county, an exemplar area of intensive agricultural production in the North China Plain. Substance flow analyses were constructed for the major crop systems in the county across the period 1983-2014. On average across all production systems between 2010 and 2014, total annual nutrient inputs to agricultural land in Huantai county remained high at 18.1kt N, 2.7kt P and 7.8kt K (696kg N ha -1 ; 104kgP ha -1 ; 300kgK ha -1 ). Whilst the application of inorganic fertiliser dominated these inputs, crop residues, atmospheric deposition and livestock manure represented significant, yet largely unrecognised, sources of nutrients, depending on the individual production system and the period of time. Whilst nutrient use efficiency (NUE) increased for N and P between 1983 and 2014, future improvements in NUE will require better alignment of nutrient inputs and crop demand. This is particularly true for high-value fruit and vegetable production, in which appropriate recognition of nutrient supply from sources such as manure and from soil reserves will be required to enhance NUE. Aligned with the structural organisation of the public agricultural extension service at county-scale in China, our analyses highlight key areas for the development of future agricultural policy and farm advice in order to rebalance the management of natural resources from a focus on production and growth towards the aims of efficiency and sustainability. Copyright © 2017 Elsevier B.V. All rights reserved.

Bioremediating Oil Spills in Nutrient Poor Ocean Waters Using Fertilized Clay Mineral Flakes: Some Experimental Constraints

PubMed Central

Warr, Laurence N.; Friese, André; Schwarz, Florian; Schauer, Frieder; Portier, Ralph J.; Basirico, Laura M.; Olson, Gregory M.

2013-01-01

Much oil spill research has focused on fertilizing hydrocarbon oxidising bacteria, but a primary limitation is the rapid dilution of additives in open waters. A new technique is presented for bioremediation by adding nutrient amendments to the oil spill using thin filmed minerals comprised largely of Fullers Earth clay. Together with adsorbed N and P fertilizers, filming additives, and organoclay, clay flakes can be engineered to float on seawater, attach to the oil, and slowly release contained nutrients. Our laboratory experiments of microbial activity on weathered source oil from the Deepwater Horizon spill in the Gulf of Mexico show fertilized clay treatment significantly enhanced bacterial respiration and consumption of alkanes compared to untreated oil-in-water conditions and reacted faster than straight fertilization. Whereas a major portion (up to 98%) of the alkane content was removed during the 1 month period of experimentation by fertilized clay flake interaction; the reduced concentration of polyaromatic hydrocarbons was not significantly different from the non-clay bearing samples. Such clay flake treatment could offer a way to more effectively apply the fertilizer to the spill in open nutrient poor waters and thus significantly reduce the extent and duration of marine oil spills, but this method is not expected to impact hydrocarbon toxicity. PMID:23864952

Bioremediating oil spills in nutrient poor ocean waters using fertilized clay mineral flakes: some experimental constraints.

PubMed

Warr, Laurence N; Friese, André; Schwarz, Florian; Schauer, Frieder; Portier, Ralph J; Basirico, Laura M; Olson, Gregory M

2013-01-01

Much oil spill research has focused on fertilizing hydrocarbon oxidising bacteria, but a primary limitation is the rapid dilution of additives in open waters. A new technique is presented for bioremediation by adding nutrient amendments to the oil spill using thin filmed minerals comprised largely of Fullers Earth clay. Together with adsorbed N and P fertilizers, filming additives, and organoclay, clay flakes can be engineered to float on seawater, attach to the oil, and slowly release contained nutrients. Our laboratory experiments of microbial activity on weathered source oil from the Deepwater Horizon spill in the Gulf of Mexico show fertilized clay treatment significantly enhanced bacterial respiration and consumption of alkanes compared to untreated oil-in-water conditions and reacted faster than straight fertilization. Whereas a major portion (up to 98%) of the alkane content was removed during the 1 month period of experimentation by fertilized clay flake interaction; the reduced concentration of polyaromatic hydrocarbons was not significantly different from the non-clay bearing samples. Such clay flake treatment could offer a way to more effectively apply the fertilizer to the spill in open nutrient poor waters and thus significantly reduce the extent and duration of marine oil spills, but this method is not expected to impact hydrocarbon toxicity.

A 3D parameterization of nutrients atmospheric deposition to the global ocean

NASA Astrophysics Data System (ADS)

Myriokefalitakis, S.; Nenes, A.; Baker, A. R.; Mihalopoulos, N.; Kanakidou, M.

2016-12-01

Atmospheric deposition of trace constituents, both of natural and anthropogenic origin, can act as a nutrient source into the open ocean and affect marine ecosystem functioning and subsequently the exchange of CO2 between the atmosphere and the global ocean. Dust is known as a major source of nutrients (such as iron and phosphorus) to the global ocean, but only a fraction of these nutrients is released in soluble form that can be assimilated by the ecosystems. The global atmospheric iron (Fe) and phosphorus (P) cycles are here parameterized in a global 3-D chemical transport model. Both primary emissions of total and soluble Fe and P associated with dust and combustion processes are taken into account. The impact of atmospheric acidity on nutrient solubility is parameterised based on experimental findings and model results are evaluated by comparison with available observations. The effect of air-quality changes on soluble nutrient deposition is studied by performing sensitivity simulations using preindustrial, present and future emission scenarios. The link between the soluble Fe and P atmospheric deposition and anthropogenic sources is also investigated. Overall, the response of the chemical composition of nutrient-containing aerosols to environmental changes is demonstrated and quantified.

Watershed delineation and nitrogen source analysis for Bayou ...

EPA Pesticide Factsheets

Nutrient pollution in stormwater runoff from urbanized areas contributes to water quality degradation in streams and receiving waterbodies. Agriculture, population growth, and industrial activities are significant sources of nitrogen inputs for surface waters. Increased nitrogen loading stimulates eutrophication through algal blooms, which leads to an overall decrease in drinking water and aquatic habitat quality. Bayou Chico, a highly urbanized watershed in the Pensacola Bay system in northwest Florida, is a nutrient-impaired waterbody under management to reduce bacteria and nutrient loadings, in accordance with the Florida Department of Environmental Protection’s (FDEP) Basin Management Action Plan. Best management practices and green infrastructure (GI) throughout Bayou Chico help reduce nitrogen inputs by retaining and filtering water. GI can function as a nitrogen sink by sorption or infiltration into soils, sequestration into plant material, and denitrification through microbial processes. However, a better understanding of the efficiency of these systems is needed to better inform management practices on future nitrogen reduction. This project will address two issues relating to the presence of nitrogen in the Bayou Chico watershed: 1) the identification of specific nitrogen sources within urbanized areas, and 2) the potential rates of nitrogen removal and sequestration from GI and nitrogen transport throughout the bayou. To accomplish these goals, nitr

Modeling of land use and reservoir effects on nonpoint source pollution in a highly agricultural basin

USGS Publications Warehouse

Wu, Yiping; Liu, Shu-Guang

2012-01-01

Nonpoint source (NPS) pollution is tightly linked to land use activities that determine the sources and magnitudes of pollutant loadings to stream water. The pollutant loads may also be alleviated within reservoirs because of the physical interception resulting from changed hydrological regimes and other biochemical processes. It is important but challenging to assess the NPS pollution processes with human effects due to the measurement limitations. The objective of this study is to evaluate the effects of human activities such as land uses and reservoir operation on the hydrological and NPS pollution processes in a highly agricultural area-the Iowa River Basin-using the Soil and Water Assessment Tool (SWAT). The evaluation of model performance at multiple sites reveals that SWAT can consistently simulate the daily streamflow, and monthly/annual sediment and nutrient loads (nitrate nitrogen and mineral phosphorus) in the basin. We also used the calibrated model to estimate the trap efficiencies of sediment (~78%) and nutrients (~30%) in the Coralville Reservoir within the basin. These non-negligible effects emphasize the significance of incorporating the sediment and nutrient removal mechanisms into watershed system studies. The spatial quantification of the critical NPS pollution loads can help identify hot-spot areas that are likely locations for the best management practices.

Modeling of land use and reservoir effects on nonpoint source pollution in a highly agricultural basin.

PubMed

Wu, Yiping; Liu, Shuguang

2012-09-01

Nonpoint source (NPS) pollution is tightly linked to land use activities that determine the sources and magnitudes of pollutant loadings to stream water. The pollutant loads may also be alleviated within reservoirs because of the physical interception resulting from changed hydrological regimes and other biochemical processes. It is important but challenging to assess the NPS pollution processes with human effects due to the measurement limitations. The objective of this study is to evaluate the effects of human activities such as land uses and reservoir operation on the hydrological and NPS pollution processes in a highly agricultural area-the Iowa River Basin-using the Soil and Water Assessment Tool (SWAT). The evaluation of model performance at multiple sites reveals that SWAT can consistently simulate the daily streamflow, and monthly/annual sediment and nutrient loads (nitrate nitrogen and mineral phosphorus) in the basin. We also used the calibrated model to estimate the trap efficiencies of sediment (∼78%) and nutrients (∼30%) in the Coralville Reservoir within the basin. These non-negligible effects emphasize the significance of incorporating the sediment and nutrient removal mechanisms into watershed system studies. The spatial quantification of the critical NPS pollution loads can help identify hot-spot areas that are likely locations for the best management practices.

Patterns of organic acids exuded by pioneering fungi from a glacier forefield are affected by carbohydrate sources

NASA Astrophysics Data System (ADS)

Brunner, Ivano; Goren, Asena; Schlumpf, Alessandro

2014-01-01

Bare soils in the area of retreating glaciers are ideal environments to study the role of microorganisms in the early soil formation and in processes of mineral weathering. The aim of our study was to investigate whether the source of carbohydrate would influence the patterns of organic acids exuded by fungal species. Three pioneering fungus species, isolated from fine granitic sediments in front of the Damma glacier from the central Swiss Alps, have previously been found to have the capability to exude organic acids and dissolve granite powder. In batch experiments, various carbohydrates, including glucose, cellulose, pectin, pollen, and cell remnants of cyanobacteria, fungi, and algae, were applied as carbohydrate sources and the patterns of exuded organic acids recorded. The results showed that two fungi, the zygomycete fungus Mucor hiemalis and the ascomycete fungus Penicillium chrysogenum, released a significantly higher amount of organic acids in dependence on specific carbohydrate sources. Pollen and algae as carbohydrate sources triggered significantly the exudation of malate in M. hiemalis, and pollen and cellulose that of oxalate in P. chrysogenum. We conclude that the occurrence of complex carbohydrate sources in nutrient-deficient deglaciated soils may positively influence the exudation of organic acids of fungi. In particular, pollen and remnants of other microorganisms can trigger the exudation of organic acids of fungi in order to promote the weathering of minerals and to make nutrients available that would otherwise be trapped in that cryospheric environment.

Impact of seasonality on the nutrient concentrations in Gautami-Godavari Estuarine Mangrove Complex, Andhra Pradesh, India.

PubMed

Rao, Karuna; Priya, Namrata; Ramanathan, A L

2018-04-01

Spatiotemporal variations of dissolved nutrients were studied along Gautami-Godavari mangrove ecosystem to delineate their sources and fate. Average values of nitrate (NO 3 - ), dissolved silica (DSi) and phosphate (PO 4 3- ) is 2.09 mg/l, 12.7 mg/l and 0.16 mg/l in wet season and 0.47 mg/l, 6.96 mg/l and 0.29 mg/l in dry season respectively. In wet season river discharge has significant influence on NO 3 - and DSi. In dry season, NO 3 - and PO 4 3- are controlled by groundwater discharge, benthic exchange and various in situ processes owing to sediment redox condition. Mixing model shows net addition of phosphate in Coringa mangroves (95%) and Lower estuary (13%) and net removal of nitrate (24.79%) in Coringa mangrove and in estuary (58.9%). Thus present mangrove acts as net source for phosphate and net sink for nitrate and DSi. Nutrient ratio shows seasonal switching between potential Phosphorus and Nitrogen limitation in wet and dry season respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

Daily consumption of foods and nutrients from institutional and home sources among young children attending two contrasting day-care centers in Guatemala City.

PubMed

Vossenaar, M; Jaramillo, P M; Soto-Méndez, M-J; Panday, B; Hamelinck, V; Bermúdez, O I; Doak, C M; Mathias, P; Solomons, N W

2012-12-01

Adequate nutrition is critical to child development and institutions such as day-care centers could potentially complement children's diets to achieve optimal daily intakes. The aim of the study was to describe the full-day diet of children, examining and contrasting the relative contribution of home-derived versus institutional energy and nutrient sources. The present comparison should be considered in the domain of a case-study format. The diets of 33, 3-6 y old children attending low-income day-care centers serving either 3 or a single meal were examined. The home-diet was assessed by means of 3 non-consecutive 24-hr recalls. Estimated energy and nutrient intakes at the centers and at home were assessed and related to Recommended Nutrient Intakes (RNI). Nutrient densities, critical densities and main sources of nutrients were computed. We observed that in children attending the day-care center serving three meals, home-foods contributed less than half the daily energy (47.7%) and between 29.9% and 53.5% of daily nutrients. In children receiving only lunch outside the home, energy contribution from the home was 83.9% and 304 kcal lower than for children receiving 3 meals. Furthermore, between 59.0% and 94.8% of daily nutrients were provided at home. Daily energy, nutrient intakes and nutrient densities were well above the nutrient requirements for this age group, and particularly high for vitamin A. The overall dietary variety was superior in the situation of greater contribution of home fare, but overall the nutrient density and adequacy of the aggregate intakes did not differ in any important manner.

Nutrient pressures and ecological responses to nutrient loading reductions in Danish streams, lakes and coastal waters

NASA Astrophysics Data System (ADS)

Kronvang, Brian; Jeppesen, Erik; Conley, Daniel J.; Søndergaard, Martin; Larsen, Søren E.; Ovesen, Niels B.; Carstensen, Jacob

2005-03-01

The Danish National Aquatic Monitoring and Assessment Programme (NOVA) was launched in 1988 following the adoption of the first Danish Action Plan on the Aquatic Environment in 1987 with the aim to reduce by 50% the nitrogen (N) loading and by 80% the phosphorus (P) loading to the aquatic environment. The 14 years of experience gathered from NOVA have shown that discharges of total N (TN) and P (TP) from point sources to the Danish Aquatic Environment have been reduced by 69% (N) and 82% (P) during the period 1989 2002. Consequently, the P concentration has decreased markedly in most Danish lakes and estuaries. Considerable changes in agricultural practice have resulted in a reduction of the net N-surplus from 136 to 88 kg N ha-1 yr-1 (41%) and the net P-surplus from 19 to 11 kg P ha-1 yr-1 (42%) during the period 1985 2002. Despite these efforts Danish agriculture is today the major source of both N (>80%) and P (>50%) in Danish streams, lakes and coastal waters. A non-parametric statistical trend analysis of TN concentrations in streams draining dominantly agricultural catchments has shown a significant (p<0.05) downward trend in 48 streams with the downward trend being stronger in loamy compared to sandy catchments, and more pronounced with increasing dominance of agricultural exploitation in the catchments. In contrast, a statistical trend analysis of TP concentrations in streams draining agricultural catchments did not reveal any significant trends. The large reduction in nutrient loading from point and non-point sources has in general improved the ecological conditions of Danish lakes in the form of increased summer Secchi depth, decreased chlorophyll a and reduced phytoplankton biomass. Major changes have also occurred in the fish communities in lakes, with positive cascading effects on water quality. In Danish estuaries and coastal waters only a few significant improvements in the ecological quality have been observed, although it is expected that the observed reduced nutrient concentrations are likely to improve the ecological quality of estuaries and coastal waters in Denmark in the long term.

Woodchip bioreactors effectively treat aquaculture effluent

USDA-ARS?s Scientific Manuscript database

Nutrients, in particular nitrogen and phosphorus, can create eutrophication problems in any watershed. Preventing water quality impairment requires controlling nutrients from both point-source and non-point source discharges. Woodchip bioreactors are one relatively new approach that can be utilized ...

Effect of elevated [CO2 ] on yield, intra-plant nutrient dynamics, and grain quality of rice cultivars in Eastern India.

PubMed

Jena, Usha Rani; Swain, Dillip Kumar; Hazra, K K; Maity, Mrinal K

2018-05-16

Climate models predict an increase in global temperature in response to a doubling of atmospheric [CO 2 ] that may impact future rice production and quality. In this study, the effect of elevated [CO 2 ] on yield, nutrient acquisition and utilization, and grain quality of rice genotypes was investigated in subtropical climate of eastern India (Kharagpur). Three environments (open field, ambient, and elevated [CO 2 ]) were tested using four rice cultivars of eastern India. Under elevated [CO 2 ] (25% higher), yield of high yielding cultivars (HYCs) viz. IR 36, Swarna, and Swarna sub1 was significantly reduced (11-13%), whereas the yield increased (6-9%) for Badshabhog, a low-yielding aromatic cultivar. Elevated [CO 2 ] significantly enhanced K uptake (14-21%), but did not influence the uptake of total N and P. The nutrient harvest index and use efficiency values in HYCs were reduced under elevated [CO 2 ] indicating that nutrients translocation from source to sink (grain) was significantly reduced. An increase in alkali spreading value (10%) and reduction in grain protein (2-3%) and iron (5-6%) was also observed upon [CO 2 ] elevation. The study highlights the importance of nutrient management (increasing N rate for HYCs) and selective breeding of tolerant cultivar in minimizing the adverse effect of elevated [CO 2 ] on rice yield and quality. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Influence of fresh water, nutrients and DOC in two submarine-groundwater-fed estuaries on the west of Ireland.

PubMed

Smith, Aisling M; Cave, Rachel R

2012-11-01

Coastal fresh water sources, which discharge to the sea are expected to be directly influenced by climate change (e.g. increased frequency of extreme weather events). Sea-level rise and changes in rainfall patterns, changes in demand for drinking water and contamination caused by population and land use change, will also have an impact. Coastal waters with submarine groundwater discharge are of particular interest as this fresh water source is very poorly quantified. Two adjacent bays which host shellfish aquaculture sites along the coast of Co. Galway in the west of Ireland have been studied to establish the influence of fresh water inputs on nutrients and dissolved organic carbon (DOC) in each bay. Neither bay has riverine input and both are underlain by the karst limestone of the Burren and are susceptible to submarine groundwater discharge. Water and suspended matter samples were collected half hourly over 13 h tidal cycles over several seasons. Water samples were analysed for nutrients and DOC, while suspended matter was analysed for organic/inorganic content. Temperature and salinity measurements were recorded during each tidal station by SBE 37 MicroCAT conductivity/temperature sensors. Long-term mooring data were used to track freshwater input for Kinvara and Aughinish Bays and compare it with rainfall data. Results show that Kinvara Bay is much more heavily influenced by fresh water input than Aughinish Bay, and this is a strong source of fixed nitrogen to Kinvara Bay. Only during flood events is there a significant input of inorganic nitrogen from fresh water to Aughinish Bay, such as in late November 2009. Fresh water input does not appear to be a significant source of dissolved inorganic phosphate (DIP) to either bay, but is a source of DOC to both bays. C:N ratios of DOC/DON show a clear distinction between marine and terrestrially derived dissolved organic material. Copyright © 2012. Published by Elsevier B.V.

Gourds: Bitter, Bottle, Wax, Snake, Sponge and Ridge

USDA-ARS?s Scientific Manuscript database

Minor cucurbits include bitter gourd, bottle gourd, wax gourd, snake gourd, and sponge and ridge gourd, which are significant dietary sources of nutrients such as vitamin A and C, iron and calcium. These cucurbits are cultivated and marketed by smallholder farmers and remain important components of ...

Time series models of decadal trends in the harmful algal species Karlodinium veneficum in Chesapeake Bay.

PubMed

Lin, Chih-Hsien Michelle; Lyubchich, Vyacheslav; Glibert, Patricia M

2018-03-01

The harmful dinoflagellate, Karlodnium veneficum, has been implicated in fish-kill and other toxic, harmful algal bloom (HAB) events in waters worldwide. Blooms of K. veneficum are known to be related to coastal nutrient enrichment but the relationship is complex because this HAB taxon relies not only on dissolved nutrients but also particulate prey, both of which have also changed over time. Here, applying cross-correlations of climate-related physical factors, nutrients and prey, with abundance of K. veneficum over a 10-year (2002-2011) period, a synthesis of the interactive effects of multiple factors on this species was developed for Chesapeake Bay, where blooms of the HAB have been increasing. Significant upward trends in the time series of K. veneficum were observed in the mesohaline stations of the Bay, but not in oligohaline tributary stations. For the mesohaline regions, riverine sources of nutrients with seasonal lags, together with particulate prey with zero lag, explained 15%-46% of the variation in the K. veneficum time series. For the oligohaline regions, nutrients and particulate prey generally showed significant decreasing trends with time, likely a reflection of nutrient reduction efforts. A conceptual model of mid-Bay blooms is presented, in which K. veneficum, derived from the oceanic end member of the Bay, may experience enhanced growth if it encounters prey originating from the tributaries with different patterns of nutrient loading and which are enriched in nitrogen. For all correlation models developed herein, prey abundance was a primary factor in predicting K. veneficum abundance. Copyright © 2018 Elsevier B.V. All rights reserved.

Variable nutrient stoichiometry (carbon:nitrogen:phosphorus) across trophic levels determines community and ecosystem properties in an oligotrophic mangrove system.

PubMed

Scharler, U M; Ulanowicz, R E; Fogel, M L; Wooller, M J; Jacobson-Meyers, M E; Lovelock, C E; Feller, I C; Frischer, M; Lee, R; McKee, K; Romero, I C; Schmit, J P; Shearer, C

2015-11-01

Our study investigated the carbon:nitrogen:phosphorus (C:N:P) stoichiometry of mangrove island of the Mesoamerican Barrier Reef (Twin Cays, Belize). The C:N:P of abiotic and biotic components of this oligotrophic ecosystem was measured and served to build networks of nutrient flows for three distinct mangrove forest zones (tall seaward fringing forest, inland dwarf forests and a transitional zone). Between forest zones, the stoichiometry of primary producers, heterotrophs and abiotic components did not change significantly, but there was a significant difference in C:N:P, and C, N, and P biomass, between the functional groups mangrove trees, other primary producers, heterotrophs, and abiotic components. C:N:P decreased with increasing trophic level. Nutrient recycling in the food webs was highest for P, and high transfer efficiencies between trophic levels of P and N also indicated an overall shortage of these nutrients when compared to C. Heterotrophs were sometimes, but not always, limited by the same nutrient as the primary producers. Mangrove trees and the primary tree consumers were P limited, whereas the invertebrates consuming leaf litter and detritus were N limited. Most compartments were limited by P or N (not by C), and the relative depletion rate of food sources was fastest for P. P transfers thus constituted a bottleneck of nutrient transfer on Twin Cays. This is the first comprehensive ecosystem study of nutrient transfers in a mangrove ecosystem, illustrating some mechanisms (e.g. recycling rates, transfer efficiencies) which oligotrophic systems use in order to build up biomass and food webs spanning various trophic levels.

Variable nutrient stoichiometry (carbon:nitrogen:phosphorus) across trophic levels determines community and ecosystem properties in an oligotrophic mangrove system

USGS Publications Warehouse

Scharler, U.M.; Ulanowicz, Robert E.; Fogel, M.L.; Wooller, M.J.; Jacobson-Meyers, M.E.; Lovelock, C.E.; Feller, I.C.; Frischer, M.; Lee, R.; Mckee, Karen L.; Romero, I.C.; Schmit, J.P.; Shearer, C.

2015-01-01

Our study investigated the carbon:nitrogen:phosphorus (C:N:P) stoichiometry of mangrove island of the Mesoamerican Barrier Reef (Twin Cays, Belize). The C:N:P of abiotic and biotic components of this oligotrophic ecosystem was measured and served to build networks of nutrient flows for three distinct mangrove forest zones (tall seaward fringing forest, inland dwarf forests and a transitional zone). Between forest zones, the stoichiometry of primary producers, heterotrophs and abiotic components did not change significantly, but there was a significant difference in C:N:P, and C, N, and P biomass, between the functional groups mangrove trees, other primary producers, heterotrophs, and abiotic components. C:N:P decreased with increasing trophic level. Nutrient recycling in the food webs was highest for P, and high transfer efficiencies between trophic levels of P and N also indicated an overall shortage of these nutrients when compared to C. Heterotrophs were sometimes, but not always, limited by the same nutrient as the primary producers. Mangrove trees and the primary tree consumers were P limited, whereas the invertebrates consuming leaf litter and detritus were N limited. Most compartments were limited by P or N (not by C), and the relative depletion rate of food sources was fastest for P. P transfers thus constituted a bottleneck of nutrient transfer on Twin Cays. This is the first comprehensive ecosystem study of nutrient transfers in a mangrove ecosystem, illustrating some mechanisms (e.g. recycling rates, transfer efficiencies) which oligotrophic systems use in order to build up biomass and food webs spanning various trophic levels.

Physico-chemical factors influencing spore germination in cyanobacterium Fischerella muscicola.

PubMed

Mishra, Biranchi N; Kaushik, Manish S; Abraham, Gerard; Singh, Pawan K

2018-06-19

Spore (akinete) formation in the heterocystous and branched filamentous cyanobacterium Fischerella muscicola involves a significant increase in cell size and formation of several endospores in each of the cells. In present study, the physico-chemical factors (pH, light sources, nutrient deficiency, nitrogen sources, carbon sources, and growth hormones) affecting the germination of spores of F. muscicola were examined. Increase in spore germination frequency was detected above pH 8 with maximum germination (46.04%) recorded at pH 9, whereas a significant decrease in germination was observed at pH 6 when compared to control (pH 7.6). Spore germination was not observed at pH 5. Among light sources germination frequency followed the following order, that is, red light (39.9%) > white light (33.8%) > yellow light (3.4%) > green light (1.3%) whereas germination did not take place in dark and blue light. Ammonium chloride (NH 4 Cl) supported maximum (99.5%) germination frequency followed by calcium nitrate (Ca(NO 3 ) 2 ), potassium nitrate (KNO 3 ), and minimum germination was observed in urea. Nutrient (phosphorus, calcium, and magnesium) deficiency significantly enhanced the germination frequency with maximum increase in magnesium (Mg) deficient condition. Further, supplementation of carbon sources (glucose, fructose, and sodium acetate) and growth hormones (IAA and GA) also enhanced the germination frequency in this cyanobacterium. Therefore, it may be concluded that, those factors supporting higher germination frequency could be considered for successful production and use of this cyanobacterium in biofertilizer and other algal production technologies. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dietary intakes vary with age among Eskimo adults of Northwest Alaska in the GOCADAN study, 2000-2003.

PubMed

Nobmann, Elizabeth D; Ponce, Rafael; Mattil, Claudia; Devereux, Richard; Dyke, Bennett; Ebbesson, Sven O E; Laston, Sandra; MacCluer, Jean; Robbins, David; Romenesko, Terry; Ruotolo, Giacomo; Wenger, Charlotte R; Howard, Barbara V

2005-04-01

Dietary factors influence the development of cardiovascular disease (CVD). The diet of Alaskan Eskimos differs from that of other populations. We surveyed Eskimo adults in Northwest Alaska to document their usual dietary intakes, differences based on gender and age, and sources of selected nutrients, and to generate appropriate dietary advice to reduce CVD. Interviewers surveyed 850 men and women 17-92 y old, using a quantitative food-frequency instrument. We observed many significant (chi(2) analysis P < 0.05) differences in nutrient intakes among 3 age-groups. Energy intake from carbohydrate was negatively related to participant age-group (P < or = 0.01). Energy intake from all fats (P < 0.001) and polyunsaturated fat (P < or = 0.01) was positively related to age-group among both men and women in contrast to other studies in which age differences were either not observed or decreased with age. Native foods were major sources of monounsaturated and polyunsaturated fats, including 56% of (n-3) fatty acids primarily from seal oil and salmon. However, Native foods contributed significantly less to the diets of young adults than to those of elders, especially among women. Store-bought foods were the main sources of energy, carbohydrate, fat, saturated fat, and fiber for all adults. Based on their nutrient density and potential to inhibit CVD, continued consumption of traditional foods is recommended. Variations in intake by age may portend changing eating patterns that will influence CVD as participants age. These data will contribute to understanding dietary risk factors for cardiovascular disease in this population.

Identification of Geologic and Anthropogenic Sources of Phosphorus to Streams in California and Portions of Adjacent States, U.S.A., Using SPARROW Modeling

NASA Astrophysics Data System (ADS)

Domagalski, J. L.

2013-12-01

The SPARROW (Spatially Referenced Regressions On Watershed Attributes) model allows for the simulation of nutrient transport at un-gauged catchments on a regional scale. The model was used to understand natural and anthropogenic factors affecting phosphorus transport in developed, undeveloped, and mixed watersheds. The SPARROW model is a statistical tool that allows for mass balance calculation of constituent sources, transport, and aquatic decay based upon a calibration of a subset of stream networks, where concentrations and discharge have been measured. Calibration is accomplished using potential sources for a given year and may include fertilizer, geological background (based on bed-sediment samples and aggregated with geochemical map units), point source discharge, and land use categories. NHD Plus version 2 was used to model the hydrologic system. Land to water transport variables tested were precipitation, permeability, soil type, tile drains, and irrigation. For this study area, point sources, cultivated land, and geological background are significant phosphorus sources to streams. Precipitation and clay content of soil are significant land to water transport variables and various stream sizes show significance with respect to aquatic decay. Specific rock types result in different levels of phosphorus loading and watershed yield. Some important geological sources are volcanic rocks (andesite and basalt), granodiorite, glacial deposits, and Mesozoic to Cenozoic marine deposits. Marine sediments vary in their phosphorus content, but are responsible for some of the highest natural phosphorus yields, especially along the Central and Southern California coast. The Miocene Monterey Formation was found to be an especially important local source in southern California. In contrast, mixed metamorphic and igneous assemblages such as argillites, peridotite, and shales of the Trinity Mountains of northern California result in some of the lowest phosphorus yields. The agriculturally productive Central Valley of California has a low amount of background phosphorus in spite of inputs from streams draining upland areas. Many years of intensive agriculture may be responsible for the decrease of soil phosphorus in that area. Watersheds with significant background sources of phosphorus and large amounts of cultivated land had some of the highest per hectare yields. Seven different stream systems important for water management, or to describe transport processes, were investigated in detail for downstream changes in sources and loads. For example, the Klamath River (Oregon and California) has intensive agriculture and andesite-derived phosphorus in the upper reach. The proportion of agricultural-derived phosphorus decreases as the river flows into California before discharge to the ocean. The river flows through at least three different types of geological background sources from high to intermediate to very low. Knowledge of the role of natural sources in developed watersheds is critical for developing nutrient management strategies and these model results will have applicability for the establishment of realistic nutrient criteria.

[Study on nutrient and salinity in soil covered with different vegetations in Shuangtaizi estuarine wetlands].

PubMed

Song, Xiao-Lin; Lü, Xian-Guo; Zhang, Zhong-Sheng; Chen, Zhi-Ke; Liu, Zheng-Mao

2011-09-01

Nutrient elements and salinity in soil covered by different vegetations including Phragmites australis (Clay.) Trin., Typha orientalis Presl., Puccinellia distans Parl, and Suaeda salsa in Shuangtaizi estuarine wetlands were investigated to study their distribution characteristics and to reveal the nutrient element variation during the vegetation succession processes. Results indicated that total potassium, total phosphorus and salinity were different significantly in soil between different plant communities while available phosphorus, total nitrogen, available nitrogen, available potassium, total sulfur, iron and soil organic carbon were different insignificantly. Correlation analysis suggested that soil organic carbon were related significantly to total nitrogen, available phosphorus, available potassium, which implied that decomposition of plant litter might be the mail source of soil nitrogen and available nutrient. Salinity was significantly related to total phosphorus and iron in soil. In Shuangtaizi estuarine wetland soil, ratios of carbon to nitrogen (R(C/N)) was in the range of 12.21-26.33 and the average value was 18.21, which was higher than 12.0. It indicated that soil organic carbon in Shuangtaizi estuarine mainly came from land but not ocean and plants contributed the most of soil organic matters. There was no significant difference in R(C/N) between soil from the four plant communities (F = 1.890, p = 0.151). R(C/N) was related significantly to sol salinity (r = 0.346 3, p = 0.035 8) and was increasing with soil salinity.

Stream restoration and sanitary infrastructure alter sources and fluxes of water, carbon, and nutrients in urban watersheds

NASA Astrophysics Data System (ADS)

Pennino, M. J.; Kaushal, S. S.; Mayer, P. M.; Utz, R. M.; Cooper, C. A.

2015-12-01

An improved understanding of sources and timing of water and nutrient fluxes associated with urban stream restoration is critical for guiding effective watershed management. We investigated how sources, fluxes, and flowpaths of water, carbon (C), nitrogen (N), and phosphorus (P) shift in response to differences in stream restoration and sanitary infrastructure. We compared a restored stream with 3 unrestored streams draining urban development and stormwater management over a 3 year period. We found that there was significantly decreased peak discharge in response to precipitation events following stream restoration. Similarly, we found that the restored stream showed significantly lower monthly peak runoff (9.4 ± 1.0 mm d-1) compared with two urban unrestored streams (ranging from 44.9 ± 4.5 to 55.4 ± 5.8 mm d-1) draining higher impervious surface cover. Peak runoff in the restored stream was more similar to a less developed stream draining extensive stormwater management (13.2 ± 1.9 mm d-1). Interestingly, the restored stream exported most carbon, nitrogen, and phosphorus loads at relatively lower streamflow than the 2 more urban streams, which exported most of their loads at higher and less frequent streamflow. Annual exports of total carbon (6.6 ± 0.5 kg ha-1 yr-1), total nitrogen (4.5 ± 0.3 kg ha-1 yr-1), and total phosphorus (161 ± 15 g ha-1 yr-1) were significantly lower in the restored stream compared to both urban unrestored streams (p < 0.05) and similar to the stream draining stormwater management. Although stream restoration appeared to potentially influence hydrology to some degree, nitrate isotope data suggested that 55 ± 1 % of the nitrate in the restored stream was derived from leaky sanitary sewers (during baseflow), similar to the unrestored streams. Longitudinal synoptic surveys of water and nitrate isotopes along all 4 watersheds suggested the importance of urban groundwater contamination from leaky piped infrastructure. Urban groundwater contamination was also suggested by additional tracer measurements including fluoride (added to drinking water) and iodide (contained in dietary salt). Our results suggest that integrating stream restoration with restoration of aging sanitary infrastructure can be critical to more effectively minimize watershed nutrient export. Given that both stream restoration and sanitary pipe repairs both involve extensive channel manipulation, they can be considered simultaneously in management strategies. In addition, ground water can be a major source of nutrient fluxes in urban watersheds, which has been less considered compared with upland sources and storm drains. Goundwater sources, fluxes, and flowpath should also be targeted in efforts to improve stream restoration strategies and prioritize hydrologic "hot spots" along watersheds where stream restoration is most likely to succeed.

Coupling of the spatial-temporal distributions of nutrients and physical conditions in the southern Yellow Sea

NASA Astrophysics Data System (ADS)

Wei, Qin-Sheng; Yu, Zhi-Gang; Wang, Bao-Dong; Fu, Ming-Zhu; Xia, Chang-Shui; Liu, Lu; Ge, Ren-Feng; Wang, Hui-Wu; Zhan, Run

2016-04-01

This study investigated the coupling of the spatial-temporal variations in nutrient distributions and physical conditions in the southern Yellow Sea (SYS) using data compiled from annual-cycle surveys conducted in 2006-2007 as well as satellite-derived sea-surface temperature (SST) images. The influence of physical dynamics on the distribution and transport of nutrients varied spatially and seasonally in the SYS. The Changjiang Diluted Water (CDW) plume (in summertime), the Subei Coastal Water (SCW) (year-round), and the Lubei Coastal Current (LCC) (in wintertime) served as important sources of nutrients in the inshore area in a dynamic environment. The saline Taiwan Warm Current (TWC) might transport nutrients to the northeast region of the Changjiang Estuary in the summer, and this nutrient source began to increase from spring to summer and decrease when autumn arrived. Three types of nutrient fronts, i.e., estuarine, offshore, and coastal, were identified. A circular nutrient front caused by cross-shelf transport of SCW in the southeast shelf bank area in the winter and spring was observed. The southeastward flow of western coastal cold water in the SYS might be an important conduit for cross-shelf nutrient exchange between the SYS and the East China Sea (ECS). The tongue-shaped low-nutrient region in the western study area in the wintertime was driven by the interaction of the southward Yellow Sea Western Coastal Current (YSWCC) and the biological activity. The vertically variable SCM (subsurface Chl-a maximum) in the central SYS was controlled by coupled physical-chemical processes that involved stratification and associated nutricline. The average nutrient fluxes into the euphotic zone due to upwelling near the frontal zone of the Yellow Sea Cold Water Mass (YSCWM) in the summer are estimated here for the first time: 1.4 ± 0.9 × 103 μmol/m2/d, 0.1 ± 0.1 × 103 μmol/m2/d, and 2.0 ± 1.3 × 103 μmol/m2/d for DIN, PO4-P, and SiO3-Si, respectively. The depletion of nutrients in the central SYS and the upwelled transport in the boundary of the YSCWM resulted in a spatial transfer of the high Chl-a zone, varying generally from the central SYS to the boundary of the YSCWM from spring to summer, and the nutrient flux associated with this upwelling could contribute significantly to local primary production. This study deepens our understanding of the mechanisms influencing the distribution and transport of nutrients in the SYS.

Assessment of macrophyte, heavy metal, and nutrient concentrations in the water of the Nairobi River, Kenya.

PubMed

Njuguna, Samwel Maina; Yan, Xue; Gituru, Robert Wahiti; Wang, Qingfeng; Wang, Jun

2017-08-16

Nairobi River tributaries are the main source of the Athi River. The Athi River basin is the fourth largest and important drainage system in Kenya covering 650 km and with a drainage area of 70,000 km 2 . Its water is used downstream by about four million people not only for irrigation but also for domestic purposes. However, its industrial, raw sewer, and agricultural pollution is alarming. In order to understand distribution and concentration of heavy metals and nutrients in the water of Nairobi River, 28 water samples were collected in the rainy season (October) of 2015 and dry season (June) of 2016. Cd, Cu, Cr, Zn, As, Pb, Fe, Ni, Mn, NO 3 - , and TP were analyzed. Only Cr, Pb, Fe, and Mn had concentrations exceeding the WHO permissible limit for drinking water. Out of the 28 sites examined in the study, one site had Pb exceeding the WHO recommended level. Similarly, three sites exceeded the same level for Cr. Only three sites were within the WHO permissible limits for drinking water for Mn while just four sites were within USEPA limit for Fe. Industrial effluent, domestic sewerage, agricultural activities, and solid waste were the main sources of pollution. Significant spatial variation of both heavy metals and nutrients concentration was observed and emanated from point source pollution. Eleven out of 31 macrophytes species that were identified along the river and its tributaries are effective heavy metal and nutrient bioaccumulators and may be used in phytoremediation.

Metal and nutrient dynamics on an aged intensive green roof.

PubMed

Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

2014-01-01

Runoff and rainfall quality was compared between an aged intensive green roof and an adjacent conventional roof surface. Nutrient concentrations in the runoff were generally below Environmental Quality Standard (EQS) values and the green roof exhibited NO3(-) retention. Cu, Pb and Zn concentrations were in excess of EQS values for the protection of surface water. Green roof runoff was also significantly higher in Fe and Pb than on the bare roof and in rainfall. Input-output fluxes revealed the green roof to be a potential source of Pb. High concentrations of Pb within the green roof soil and bare roof dusts provide a potential source of Pb in runoff. The origin of the Pb is likely from historic urban atmospheric deposition. Aged green roofs may therefore act as a source of legacy metal pollution. This needs to be considered when constructing green roofs with the aim of improving pollution remediation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Historical δ15N records of Saccharina specimens from oligotrophic waters of Japan Sea (Hokkaido)

PubMed Central

Kuribayashi, Takanori; Abe, Tsuyoshi; Montani, Shigeru

2017-01-01

Historically Saccharina spp. beds occurred along the west coast of Hokkaido, an oligotrophic area, and were commercially exploited. Currently extensive commercial Saccharina spp. beds do not form due to nutrient limitations. Here, we postulate that nutrients assimilated by paleo-Saccharina spp. beds may have been derived from spawning herrings (Clupea pallasii) acting as organisms that formed a vector from their feeding grounds (Okhotsk Sea and Pacific Ocean) to their spawning area (west coast of Hokkaido, Japan Sea). To test this hypothesis we examined stable nitrogen isotope ratios (δ15N) of 100– to 135–year-old Saccharina specimens preserved at the Herbarium (Hokkaido University Museum). δ15N values of the paleo-Saccharina specimens collected from this region were in the range of 10‰, which is significantly higher than the current 3–7‰ in freshly sampled Saccharina spp. This high δ15N indicates that spawning herring (Clupea pallasii) had potentially been a significant source of dissolved inorganic nitrogen (DIN) absorbed by Saccharina, acting as an organism forming a vector for transporting nutrients from eutrophic to oligotrophic coastal ecosystems. Our findings support the hypothesis of so-called “herring-derived nutrients.” PMID:28704453

A spatial and seasonal assessment of river water chemistry across North West England.

PubMed

Rothwell, J J; Dise, N B; Taylor, K G; Allott, T E H; Scholefield, P; Davies, H; Neal, C

2010-01-15

This paper presents information on the spatial and seasonal patterns of river water chemistry at approximately 800 sites in North West England based on data from the Environment Agency regional monitoring programme. Within a GIS framework, the linkages between average water chemistry (pH, sulphate, base cations, nutrients and metals) catchment characteristics (topography, land cover, soil hydrology, base flow index and geology), rainfall, deposition chemistry and geo-spatial information on discharge consents (point sources) are examined. Water quality maps reveal that there is a clear distinction between the uplands and lowlands. Upland waters are acidic and have low concentrations of base cations, explained by background geological sources and land cover. Localised high concentrations of metals occur in areas of the Cumbrian Fells which are subjected to mining effluent inputs. Nutrient concentrations are low in the uplands with the exception sites receiving effluent inputs from rural point sources. In the lowlands, both past and present human activities have a major impact on river water chemistry, especially in the urban and industrial heartlands of Greater Manchester, south Lancashire and Merseyside. Over 40% of the sites have average orthophosphate concentrations >0.1mg-Pl(-1). Results suggest that the dominant control on orthophosphate concentrations is point source contributions from sewage effluent inputs. Diffuse agricultural sources are also important, although this influence is masked by the impact of point sources. Average nitrate concentrations are linked to the coverage of arable land, although sewage effluent inputs have a significant effect on nitrate concentrations. Metal concentrations in the lowlands are linked to diffuse and point sources. The study demonstrates that point sources, as well as diffuse sources, need to be considered when targeting measures for the effective reduction in river nutrient concentrations. This issue is clearly important with regards to the European Union Water Framework Directive, eutrophication and river water quality. Copyright 2009 Elsevier B.V. All rights reserved.

Spatial distribution and assessment of nutrient pollution in Lake Toba using 2D-multi layers hydrodynamic model and DPSIR framework

NASA Astrophysics Data System (ADS)

Sunaryani, A.; Harsono, E.; Rustini, H. A.; Nomosatryo, S.

2018-02-01

Lake Toba is the largest lake in Indonesia utilized as a source of life-support for drinking and clean water, energy sources, aquaculture and tourism. Nowadays the water quality in Lake Toba has decreased due to the presence of excessive nutrient (nitrogen: N and phosphorus: P). This study aims to describe the spatial distribution of nutrient pollution and to develop a decision support tool for the identification and evaluation of nutrient pollution control in Lake Toba. Spatial distribution method was conducted by 2D-multi layers hydrodynamic model, while DPSIR Framework is used as a tool for the assessment. The results showed that the concentration of nutrient was low and tended to increase along the water depth, but nutrient concentration in aquaculture zones was very high and the trophic state index has reached eutrophic state. The principal anthropogenic driving forces were population growth and the development of aquaculture, livestock, agriculture, and tourism. The main environmental pressures showed that aquaculture and livestock waste are the most important nutrient sources (93% of N and 87% of P loads). State analysis showed that high nutrient concentration and increased algal growth lead to oxygen depletion. The impacts of these conditions were massive fish kills, loss of amenities and tourism value, also decreased usability of clean water supply. This study can be a useful information for decision-makers to evaluate nutrient pollution control. Nutrient pollution issue in Lake Toba requires the attention of local government and public society to maintain its sustainability.

Atmospheric Transport of Nutrient Matter during a Red Tide Event

NASA Astrophysics Data System (ADS)

Tian, R.; Weng, H.; Lin, Q.

2017-12-01

Harmful algal blooms (HABs) resulting from an explosive increase in algae population have become a global problem in coastal marine environment. During 3rd -8th, May of 2006, large-scale, mixed prorocentrum dentatum stein and skeletonema costatum bloom developed in those water off the coast of Zhejiang province (Zhoushan city and Liuheng Island) of China. Using Global Nested Air Quality Prediction Modeling System (GNAQPMS), we find an atmospheric transport of considerable nutrient matter (nitrate, ammonium, Fe (Ⅱ)) to East China Sea (ECS) before the red tide event. It be inferred that the atmospheric transport of nutrient matter is a significant source of nutrient matter in the water of East China Sea whose hydrological setting is dominated by oligotrophic Taiwan Warm Current in spring. Such atmospheric transport of nutrient matter is likely a cause factor of red tide in the coast of East China Sea, especially during dust event. The study provides new information for discovering the occurring mechanism of the red tides in ECS and the essential parameters for the red tide research.

The nutrient value of Imbrasia belina Lepidoptera: Saturnidae (madora).

PubMed

Onigbinde, A O; Adamolekun, B

1998-05-01

To determine the pattern of consumption of Imbrasia belina (madora) and other edible insects and also compare the nutrient values of madora larvae and two of its variants (Anaphe venata and Cirina forda) to those of some conventional sources of protein. University of Zimbabwe. 100 workers who admitted to a history of entomophagy. Popularity score of madora compared with those of other edible insects and approximate compositions of nutrients in the larvae compared with standard proteins. Most respondents (65%) were introduced to entomophagy by their parents. Termites were the most frequently consumed, followed by madora. More respondents ate insects because of their perceived nutritional value than because of their relative availability. There was no association of entomophagy with significant side effects. The protein, fat and mineral contents of the larvae were superior to those of beef and chicken. There were no major differences in the nutrient composition of the three Lepidoptera variants. The high nutrient value and low cost of these larvae make them an important protein supplement, especially for people in the low income group.

Hydrologic and nutrient response of groundwater to flooding of cranberry farms in southeastern Massachusetts, USA

USDA-ARS?s Scientific Manuscript database

Seasonal flooding of cranberry farms is essential for long-term sustainability of cranberry production in southeastern Massachusetts, with roughly 90% of growers flooding for fall harvesting and winter protection. Although considered a significant source of recharge to the regional unconfined aquif...

Effect of topographic characteristics on compound topographic index for identification of gully channel initiation locations

USDA-ARS?s Scientific Manuscript database

Sediment loads from gully erosion can be a significant sediment source within watershed resulting in major contributions to water quality problems, reduction of crop productivity by removal of nutrient rich top soil, and damaging downstream ecosystems. Areas containing a high probability of forming ...

A free new dietary supplement label database for dietitians

USDA-ARS?s Scientific Manuscript database

Over half of US adults consume dietary supplements (DS). Some of the approximately 50,000 products on the market provide significant sources of nutrients or other bioactive constituents. It is important for dietitians to have information about them. In keeping with their missions, the Office of Di...

Nutrient sequestration in Aquitaine lakes (SW France) limits nutrient flux to the coastal zone

NASA Astrophysics Data System (ADS)

Buquet, Damien; Anschutz, Pierre; Charbonnier, Céline; Rapin, Anne; Sinays, Rémy; Canredon, Axel; Bujan, Stéphane; Poirier, Dominique

2017-12-01

Oligotrophic coastal zones are disappearing from increased nutrient loading. The quantity of nutrients reaching the coast is determined not only by their original source (e.g. fertilizers used in agriculture, waste water discharges) and the land use, but also by the pathways through which nutrients are cycled from the source to the river mouth. In particular, lakes sequester nutrients and, hence, reduce downstream transfer of nutrients to coastal environments. Here, we quantify the impact of Aquitaine great lakes on the fluxes of dissolved macro-nutrients (N, P, Si) to the Bay of Biscay. For that, we have measured nutrient concentrations and fluxes in 2014 upstream and downstream lakes of Lacanau and Carcans-Hourtin, which belongs to the catchment of the Arcachon Bay, which is the largest coastal lagoon of the Bay of Biscay French coast. Data were compared to values obtained from the Leyre river, the main freshwater and nutrient source for the lagoon. Results show that processes in lakes greatly limit nutrient flux to the lagoon compared to fluxes from Leyre river, although the watershed is similar in terms of land cover. In lakes, phosphorus and silicon are trapped for long term in the sediment, silicon as amorphous biogenic silica and phosphorus as organic P and P associated with Fe-oxides. Nitrogen that enters lakes mostly as nitrate is used for primary production. N is mineralized in the sediment; a fraction diffuses as ammonium. N2 production through benthic denitrification extracts only 10% of dissolved inorganic nitrogen from the aquatic system. The main part is sequestered in organic-rich sediment that accumulates below 5 m depth in both lakes.

Design of a Nutrient Reclamation System for the Cultivation of Microalgae for Biofuel Production and Other Industrial Applications

NASA Astrophysics Data System (ADS)

Sandefur, Heather Nicole

Microalgal biomass has been identified as a promising feedstock for a number of industrial applications, including the synthesis of new pharmaceutical and biofuel products. However, there are several economic limitations associated with the scale up of existing algal production processes. Critical economic studies of algae-based industrial processes highlight the high cost of supplying essential nutrients to microalgae cultures. With microalgae cells having relatively high nitrogen contents (4 to 8%), the N fertilizer cost in industrial-scale production is significant. In addition, the disposal of the large volumes of cell residuals that are generated during product extraction stages can pose other economic challenges. While waste streams can provide a concentrated source of nutrients, concerns about the presence of biological contaminants and the expense of heat treatment pose challenges to processes that use wastewater as a nutrient source in microalgae cultures. The goal of this study was to evaluate the potential application of ultrafiltration technology to aid in the utilization of agricultural wastewater in the cultivation of a high-value microalgae strain. An ultrafiltration system was used to remove inorganic solids and biological contaminants from wastewater taken from a swine farm in Savoy, Arkansas. The permeate from the system was then used as the nutrient source for the cultivation of the marine microalgae Porphyridium cruentum. During the ultrafiltration system operation, little membrane fouling was observed, and permeate fluxes remained relatively constant during both short-term and long-term tests. The complete rejection of E. coli and coliforms from the wastewater was also observed, in addition to a 75% reduction in total solids, including inorganic materials. The processed permeate was shown to have very high concentrations of total nitrogen (695.6 mg L-1) and total phosphorus (69.1 mg L-1 ). In addition, the growth of P. cruentum was analyzed in a medium containing swine waste permeate, and was compared to P. cruentum growth in a control medium. A higher biomass productivity, lipid productivity, and lipid content were observed in the microalgae cultivated in the swine waste medium compared to that of the control medium. These results suggest that, through the use of ultrafiltration technology as an alternative to traditional heat treatment, agricultural wastewaters could be effectively utilized as a nutrient source for microalgae cultivation.

THE ASSOCIATION OF LAND USE/LAND COVER AND NUTRIENT LEVELS IN MARYLAND STREAMS

EPA Science Inventory

Anthropogenic nonpoint sources of nutrients are known to cause accelerated eutrophication of estuaries. The Chesapeake Bay is one of the world's largest estuaries exhibiting the eutrophication problem caused by pollution from various land use activities. The sources contributing ...

21 CFR 101.54 - Nutrient content claims for “good source,” “high,” “more,” and “high potency.”

Code of Federal Regulations, 2011 CFR

2011-04-01

... antioxidant activity; that is, when there exists scientific evidence that, following absorption from the... of the nutrients with recognized antioxidant activity. The list of nutrients shall appear in letters... the term “antioxidant.” A nutrient content claim that characterizes the level of antioxidant nutrients...

21 CFR 101.54 - Nutrient content claims for “good source,” “high,” “more,” and “high potency.”

Code of Federal Regulations, 2010 CFR

2010-04-01

... antioxidant activity; that is, when there exists scientific evidence that, following absorption from the... of the nutrients with recognized antioxidant activity. The list of nutrients shall appear in letters... the term “antioxidant.” A nutrient content claim that characterizes the level of antioxidant nutrients...

Habitat-specific nutrient removal and release in Oregon salt marshes

EPA Science Inventory

Wetlands can be sources, sinks and transformers of nutrients, although it is their role in nutrient removal that is valued as a water purification ecosystem service. In order to quantify that service for any wetland, it is important to understand the drivers of nutrient removal w...

Nutrients in the Nation?s streams and groundwater: National Findings and Implications

USGS Publications Warehouse

Dubrovsky, Neil M.; Hamilton, Pixie A.

2010-01-01

A comprehensive national analysis of the distribution and trends of nutrient concentrations in streams and groundwater from 1992 through 2004 is provided by the National Water-Quality Assessment (NAWQA) Program of the United States Geological Survey (USGS). Findings describe the distribution and causes of varying nutrient concentrations in streams and groundwater throughout the Nation and examine the primary sources that contribute to elevated concentrations. Results show that excessive nutrient enrichment is a widespread cause of ecological degradation in streams and that nitrate contamination of groundwater used for drinking water, particularly shallow domestic wells in agricultural areas, is a continuing human-health concern. Finally, despite major Federal, State and local nonpoint-source nutrient control efforts for streams and watersheds across the Nation, USGS trend analyses for 1993?2003 suggest limited national progress to reduce the impacts of nonpoint sources of nutrients during this period. Instead, concentrations have remained the same or increased in many streams and aquifers across the Nation, and continue to pose risks to aquatic life and human health. This Fact Sheet highlights selected national findings and their implications, and serves as a companion product to the complete analysis reported in the USGS Circular titled ?The Quality of Our Nation?s Waters?Nutrients in the Nation?s Streams and Groundwater, 1992?2004.?

Potential for nutrient recovery and biogas production from blackwater, food waste and greywater in urban source control systems.

PubMed

Kjerstadius, H; Haghighatafshar, S; Davidsson, Å

2015-01-01

In the last decades, the focus on waste and wastewater treatment systems has shifted towards increased recovery of energy and nutrients. Separation of urban food waste (FW) and domestic wastewaters using source control systems could aid this increase; however, their effect on overall sustainability is unknown. To obtain indicators for sustainability assessments, five urban systems for collection, transport, treatment and nutrient recovery from blackwater, greywater and FW were investigated using data from implementations in Sweden or northern Europe. The systems were evaluated against their potential for biogas production and nutrient recovery by the use of mass balances for organic material, nutrients and metals over the system components. The resulting indicators are presented in units suitable for use in future sustainability studies or life-cycle assessment of urban waste and wastewater systems. The indicators show that source control systems have the potential to increase biogas production by more than 70% compared with a conventional system and give a high recovery of phosphorus and nitrogen as biofertilizer. The total potential increase in gross energy equivalence for source control systems was 20-100%; the greatest increase shown is for vacuum-based systems.

Field drains as a route of rapid nutrient export from agricultural land receiving biosolids.

PubMed

Heathwaite, A L; Burke, S P; Bolton, L

2006-07-15

We report research on the environmental risk of incidental nutrient transfers from land to water for biosolids amended soils. We show that subsurface (drainflow) pathways of P transport may result in significant concentrations, up to 10 mg total P l(-1), in the drainage network of an arable catchment when a P source (recent biosolids application) coincides with a significant and active transport pathway (rainfall event). However, the high P concentrations were short-lived, with drainage ditch total P concentrations returning to pre-storm concentrations within a few days of the storm event. In the case of the drainflow concentrations reported here, the results are unusual in that they describe an 'incidental event' for a groundwater catchment where such events might normally be expected to be rare owing to the capacity of the hydrological system to attenuate nutrient fluxes for highly adsorbed elements such as P. Consequently, there is a potential risk of P transfers to shallow groundwater systems. We suggest that the findings are not specific to biosolids-alone, which is a highly regulated industry, but that similar results may be anticipated had livestock waste or mineral fertilizer been applied, although the magnitude of losses may differ. The risk appears to be more one of timing and the availability of a rapid transport pathway than of P source.

Effect of bacterial root symbiosis and urea as source of nitrogen on performance of soybean plants grown hydroponically for Bioregenerative Life Support Systems (BLSSs)

PubMed Central

Paradiso, Roberta; Buonomo, Roberta; Dixon, Mike A.; Barbieri, Giancarlo; De Pascale, Stefania

2015-01-01

Soybean is traditionally grown in soil, where root symbiosis with Bradyrhizobium japonicum can supply nitrogen (N), by means of bacterial fixation of atmospheric N2. Nitrogen fertilizers inhibit N-fixing bacteria. However, urea is profitably used in soybean cultivation in soil, where urease enzymes of telluric microbes catalyze the hydrolysis to ammonium, which has a lighter inhibitory effect compared to nitrate. Previous researches demonstrated that soybean can be grown hydroponically with recirculating complete nitrate-based nutrient solutions. In Space, urea derived from crew urine could be used as N source, with positive effects in resource procurement and waste recycling. However, whether the plants are able to use urea as the sole source of N and its effect on root symbiosis with B. japonicum is still unclear in hydroponics. We compared the effect of two N sources, nitrate and urea, on plant growth and physiology, and seed yield and quality of soybean grown in closed-loop Nutrient Film Technique (NFT) in growth chamber, with or without inoculation with B. japonicum. Urea limited plant growth and seed yield compared to nitrate by determining nutrient deficiency, due to its low utilization efficiency in the early developmental stages, and reduced nutrients uptake (K, Ca, and Mg) throughout the whole growing cycle. Root inoculation with B. japonicum did not improve plant performance, regardless of the N source. Specifically, nodulation increased under fertigation with urea compared to nitrate, but this effect did not result in higher leaf N content and better biomass and seed production. Urea was not suitable as sole N source for soybean in closed-loop NFT. However, the ability to use urea increased from young to adult plants, suggesting the possibility to apply it during reproductive phase or in combination with nitrate in earlier developmental stages. Root symbiosis did not contribute significantly to N nutrition and did not enhance the plant ability to use urea, possibly because of ineffective infection process and nodule functioning in hydroponics. PMID:26579144

Nitrogen Flux in Watersheds: The Role of Soil Distributions and Climate in Nitrogen Flux to the Coastal Ecosystems

NASA Astrophysics Data System (ADS)

Showers, W. J.; Reyes, M. M.; Genna, B. J.

2009-12-01

Quantifying the flux of nitrate from different landscape sources in watersheds is important to understand the increased flux of nitrogen to coastal ecosystems. Recent technological advances in chemical sensor networks has demonstrated that chemical variability in aquatic environments are chronically under-sampled, and that many nutrient monitoring programs with monthly or daily sampling rates are inadequate to characterize the dominate seasonal, daily or semi-diurnal fluxes in watersheds. The RiverNet program has measured the nitrate flux in the Neuse River Basin, NC on a 15 minute interval over the past eight years. Significant diurnal variation has been observed in nitrate concentrations during high and low flow periods associated with waste water treatment plants in urban watersheds that are not present in agricultural watersheds. Discharge and N flux in the basin also has significant inter-annual variations associated with El Nino oscillations modified by the North Atlantic oscillation. Positive JMA and NAO indexes are associated with increased groundwater levels, nutrient fluxes, and estuary fish kills. To understand how climate oscillation affect discharge and nutrient fluxes, we have monitored runoff/drainages and groundwater inputs adjacent to a large waste application field over the past 4 years, and used the nitrate inputs as a tracer. Surface water run off is well correlated to precipitation patterns and is the largest nutrient flux into the river. Groundwater inputs are variable spatially and temporally, and are controlled by geology and groundwater levels. Hydric soil spatial distributions are an excellent predictor of nutrient transport across landscapes, and is related to the distribution of biogeochemical “hotspots” The isotopic composition of oxygen and nitrogen in dissolved nitrate indicate that sources change with discharge state, and that atmospherically deposited nitrogen is only important to river fluxes in forested and urban watersheds. These results also indicate that the contribution of wastewater treatment plants from urban watersheds has been greatly under-estimated in current models. Prediction of future changes in discharge and nutrient flux by the modeling of climate oscillations has important implications for water resources policy and drought management for public policy and utility managers.

Dynamics of submarine groundwater discharge and associated fluxes of dissolved nutrients, carbon, and trace gases to the coastal zone (Okatee River estuary, South Carolina)

USGS Publications Warehouse

Porubsky, W.P.; Weston, N.B.; Moore, W.S.; Ruppel, C.; Joye, S.B.

2014-01-01

Multiple techniques, including thermal infrared aerial remote sensing, geophysical and geological data, geochemical characterization and radium isotopes, were used to evaluate the role of groundwater as a source of dissolved nutrients, carbon, and trace gases to the Okatee River estuary, South Carolina. Thermal infrared aerial remote sensing surveys illustrated the presence of multiple submarine groundwater discharge sites in Okatee headwaters. Significant relationships were observed between groundwater geochemical constituents and 226Ra activity in groundwater with higher 226Ra activity correlated to higher concentrations of organics, dissolved inorganic carbon, nutrients, and trace gases to the Okatee system. A system-level radium mass balance confirmed a substantial submarine groundwater discharge contribution of these constituents to the Okatee River. Diffusive benthic flux measurements and potential denitrification rate assays tracked the fate of constituents in creek bank sediments. Diffusive benthic fluxes were substantially lower than calculated radium-based submarine groundwater discharge inputs, showing that advection of groundwater-derived nutrients dominated fluxes in the system. While a considerable potential for denitrification in tidal creek bank sediments was noted, in situ denitrification rates were nitrate-limited, making intertidal sediments an inefficient nitrogen sink in this system. Groundwater geochemical data indicated significant differences in groundwater chemical composition and radium activity ratios between the eastern and western sides of the river; these likely arose from the distinct hydrological regimes observed in each area. Groundwater from the western side of the Okatee headwaters was characterized by higher concentrations of dissolved organic and inorganic carbon, dissolved organic nitrogen, inorganic nutrients and reduced metabolites and trace gases, i.e. methane and nitrous oxide, than groundwater from the eastern side. Differences in microbial sulfate reduction, organic matter supply, and/or groundwater residence time likely contributed to this pattern. The contrasting features of the east and west sub-marsh zones highlight the need for multiple techniques for characterization of submarine groundwater discharge sources and the impact of biogeochemical processes on the delivery of nutrients and carbon to coastal areas via submarine groundwater discharge.

Food waste as nutrient source in heterotrophic microalgae cultivation.

PubMed

Pleissner, Daniel; Lam, Wan Chi; Sun, Zheng; Lin, Carol Sze Ki

2013-06-01

Glucose, free amino nitrogen (FAN), and phosphate were recovered from food waste by fungal hydrolysis using Aspergillus awamori and Aspergillus oryzae. Using 100g food waste (dry weight), 31.9 g glucose, 0.28 g FAN, and 0.38 g phosphate were recovered after 24h of hydrolysis. The pure hydrolysate has then been used as culture medium and nutrient source for the two heterotrophic microalgae Schizochytrium mangrovei and Chlorella pyrenoidosa, S. mangrovei and C. pyrenoidosa grew well on the complex food waste hydrolysate by utilizing the nutrients recovered. At the end of fermentation 10-20 g biomass were produced rich in carbohydrates, lipids, proteins, and saturated and polyunsaturated fatty acids. Results of this study revealed the potential of food waste hydrolysate as culture medium and nutrient source in microalgae cultivation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Dynamics of Inorganic Nutrients in Intertidal Sediments: Porewater, Exchangeable, and Intracellular Pools

PubMed Central

Garcia-Robledo, Emilio; Bohorquez, Julio; Corzo, Alfonso; Jimenez-Arias, Juan L.; Papaspyrou, Sokratis

2016-01-01

The study of inorganic nutrients dynamics in shallow sediments usually focuses on two main pools: porewater (PW) nutrients and exchangeable (EX) ammonium and phosphate. Recently, it has been found that microphytobenthos (MPB) and other microorganisms can accumulate large amounts of nutrients intracellularly (IC), highlighting the biogeochemical importance of this nutrient pool. Storing nutrients could support the growth of autotrophs when nutrients are not available, and could also provide alternative electron acceptors for dissimilatory processes such as nitrate reduction. Here, we studied the magnitude and relative importance of these three nutrient pools (PW, IC, and EX) and their relation to chlorophylls (used as a proxy for MPB abundance) and organic matter (OM) contents in an intertidal mudflat of Cadiz Bay (Spain). MPB was localized in the first 4 mm of the sediment and showed a clear seasonal pattern; highest chlorophylls content was found during autumn and lowest during spring-summer. The temporal and spatial distribution of nutrients pools and MPB were largely correlated. Ammonium was higher in the IC and EX fractions, representing on average 59 and 37% of the total ammonium pool, respectively. Similarly, phosphate in the IC and EX fractions accounted on average for 40 and 31% of the total phosphate pool, respectively. Nitrate in the PW was low, suggesting low nitrification activity and rapid consumption. Nitrate accumulated in the IC pool during periods of moderate MPB abundance, being up to 66% of the total nitrate pool, whereas it decreased when chlorophyll concentration peaked likely due to a high nitrogen demand. EX-Nitrate accounted for the largest fraction of total sediment nitrate, 66% on average. The distribution of EX-Nitrate was significantly correlated with chlorophyll and OM, which probably indicates a relation of this pool to an increased availability of sites for ionic adsorption. This EX-Nitrate pool could represent an alternative nitrate source with significant concentrations available to the microbial community, deeper in the sediment below the oxic layer. PMID:27303370

Ecosystem responses to long-term nutrient management in an urban estuary: Tampa Bay, Florida, USA

NASA Astrophysics Data System (ADS)

Greening, H.; Janicki, A.; Sherwood, E. T.; Pribble, R.; Johansson, J. O. R.

2014-12-01

In subtropical Tampa Bay, Florida, USA, we evaluated restoration trajectories before and after nutrient management strategies were implemented using long-term trends in nutrient loading, water quality, primary production, and seagrass extent. Following citizen demands for action, reduction in wastewater nutrient loading of approximately 90% in the late 1970s lowered external total nitrogen (TN) loading by more than 50% within three years. Continuing nutrient management actions from public and private sectors were associated with a steadily declining TN load rate and with concomitant reduction in chlorophyll-a concentrations and ambient nutrient concentrations since the mid-1980s, despite an increase of more than 1 M people living within the Tampa Bay metropolitan area. Water quality (chlorophyll-a concentration, water clarity as indicated by Secchi disk depth, total nitrogen concentration and dissolved oxygen) and seagrass coverage are approaching conditions observed in the 1950s, before the large increases in human population in the watershed. Following recovery from an extreme weather event in 1997-1998, water clarity increased significantly and seagrass is expanding at a rate significantly different than before the event, suggesting a feedback mechanism as observed in other systems. Key elements supporting the nutrient management strategy and concomitant ecosystem recovery in Tampa Bay include: 1) active community involvement, including agreement about quantifiable restoration goals; 2) regulatory and voluntary reduction in nutrient loadings from point, atmospheric, and nonpoint sources; 3) long-term water quality and seagrass extent monitoring; and 4) a commitment from public and private sectors to work together to attain restoration goals. A shift from a turbid, phytoplankton-based system to a clear water, seagrass-based system that began in the 1980s following comprehensive nutrient loading reductions has resulted in a present-day Tampa Bay which looks and functions much like it did in the relatively pre-disturbance 1950s period.

Dynamics of Inorganic Nutrients in Intertidal Sediments: Porewater, Exchangeable, and Intracellular Pools.

PubMed

Garcia-Robledo, Emilio; Bohorquez, Julio; Corzo, Alfonso; Jimenez-Arias, Juan L; Papaspyrou, Sokratis

2016-01-01

The study of inorganic nutrients dynamics in shallow sediments usually focuses on two main pools: porewater (PW) nutrients and exchangeable (EX) ammonium and phosphate. Recently, it has been found that microphytobenthos (MPB) and other microorganisms can accumulate large amounts of nutrients intracellularly (IC), highlighting the biogeochemical importance of this nutrient pool. Storing nutrients could support the growth of autotrophs when nutrients are not available, and could also provide alternative electron acceptors for dissimilatory processes such as nitrate reduction. Here, we studied the magnitude and relative importance of these three nutrient pools (PW, IC, and EX) and their relation to chlorophylls (used as a proxy for MPB abundance) and organic matter (OM) contents in an intertidal mudflat of Cadiz Bay (Spain). MPB was localized in the first 4 mm of the sediment and showed a clear seasonal pattern; highest chlorophylls content was found during autumn and lowest during spring-summer. The temporal and spatial distribution of nutrients pools and MPB were largely correlated. Ammonium was higher in the IC and EX fractions, representing on average 59 and 37% of the total ammonium pool, respectively. Similarly, phosphate in the IC and EX fractions accounted on average for 40 and 31% of the total phosphate pool, respectively. Nitrate in the PW was low, suggesting low nitrification activity and rapid consumption. Nitrate accumulated in the IC pool during periods of moderate MPB abundance, being up to 66% of the total nitrate pool, whereas it decreased when chlorophyll concentration peaked likely due to a high nitrogen demand. EX-Nitrate accounted for the largest fraction of total sediment nitrate, 66% on average. The distribution of EX-Nitrate was significantly correlated with chlorophyll and OM, which probably indicates a relation of this pool to an increased availability of sites for ionic adsorption. This EX-Nitrate pool could represent an alternative nitrate source with significant concentrations available to the microbial community, deeper in the sediment below the oxic layer.

Human waste: An underestimated source of nutrient pollution in coastal seas of Bangladesh, India and Pakistan.

PubMed

Amin, Md Nurul; Kroeze, Carolien; Strokal, Maryna

2017-05-15

Many people practice open defecation in south Asia. As a result, lot of human waste containing nutrients such as nitrogen (N) and phosphorus (P) enter rivers. Rivers transport these nutrients to coastal waters, resulting in marine pollution. This source of nutrient pollution is, however, ignored in many nutrient models. We quantify nutrient export by large rivers to coastal seas of Bangladesh, India and Pakistan, and the associated eutrophication potential in 2000 and 2050. Our new estimates for N and P inputs from human waste are one to two orders of magnitude higher than earlier model calculations. This leads to higher river export of nutrients to coastal seas, increasing the risk of coastal eutrophication potential (ICEP). The newly calculated future ICEP, for instance, Godavori river is 3 times higher than according to earlier studies. Our modeling approach is simple and transparent and can easily be applied to other data-poor basins. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nutrient cycles in agricultural systems at sub-catchment scale within the UK and China

NASA Astrophysics Data System (ADS)

Bellarby, Jessica; Surridge, Ben; Haygarth, Philip M.; Lai, Xin; Zhang, Guilong; Song, Xiaolong; Zhou, Jianbin; Meng, Fanqiao; Shen, Jianbo; Rahn, Clive; Smith, Laurence; Burke, Sean

2015-04-01

Diffuse water pollution from agriculture (DWPA) represents a significant challenge in both the UK and China. The UK has developed policies and practices which seek to mitigate DWPA, yet the risks and adverse impacts of DWPA remain widespread. In contrast, China's past priorities have largely focussed on food security, with an emphasis on increasing food production through high fertiliser application rates with little attention being paid to enhanced nutrient export from land to water and to air. This has contributed to severe environmental problems which are only now beginning to be recognised and addressed. We have prepared nutrient balances (phosphorus and nitrogen) in contrasting agricultural production systems at sub-catchment scale within China and the UK. These draw from a variety of sources ranging from general yearly statistics collected by the respective government to farm surveys. Our aim is to use the resulting nutrient balances to underpin the sharing of knowledge and innovation to mitigate DWPA in both nations. In the UK, the case studies focus on the three Demonstration Test Catchment locations, covering a range of livestock and arable production systems across England. Here, the high frequency monitoring of phosphorus river loads enables the cross-validation of the simple nutrient budget approaches applied in this study. In China, our case studies span kiwi orchard, fruit and vegetable solar greenhouse systems, double cropped rice-wheat and wheat-maize production systems. Substantial differences in nutrient stocks and flows exist between individual production systems both across and within the two countries. These differences will be expressed along the source-mobilisation-delivery-impact continuum that underpins our budgets for both phosphorus and nitrogen. We will present the phosphorus cycles of some case studies and highlight their challenges and relevance at sub-catchment scale. Based on our nutrient budgets, general recommendations can be formulated to mitigate DWPA from farm to policy levels.

Nitrogen Eutrophication on the Colorado Plateau: Using Biological Indicators to Detect Nutrient Enrichment in the Grand Canyon Region

NASA Astrophysics Data System (ADS)

Kenkel, J. A.; Johnson, N.; Hultine, K. R.; Sesnie, S.; Sisk, T.

2012-12-01

Human activities have more than doubled the availability of biologically reactive forms of nitrogen (N) since the industrial and agricultural revolutions. Though N is an important plant nutrient, increased deposition initiates a cascade of deleterious effects including ecosystem acidification, biodiversity loss, and increased smog and haze. Atmospheric pollution continues to threaten the air quality of the 16 Class 1 Wilderness areas on the Colorado Plateau, including Grand Canyon National Park (GCNP). However, the ecological impacts of N deposition in these historically N-limited, nutrient sensitive arid regions, are little- known. Here, we report baseline atmospheric and terrestrial responses to anthropogenic N deposition derived from vehicular exhaust in GCNP and long-range deposition from a local coal-fired power plant, the Navajo Generating Station (NGS). We used passive air samplers, natural abundance δ15N stable isotope analysis, and nutrient analysis to observe N patterns in air, soils, and pinyon pine (Pinus edulis) foliage. In GCNP, samples were collected from ten sites over an eight-month period in areas of projected low to high vehicular N deposition (i.e. distance from primary roadways). On the Paria Plateau, northeast of GCNP and in close proximity to the NGS, samples were collected along a distance gradient from the NGS, across the Plateau. In both study areas, atmospheric deposition, as well as soil and pine- needle nutrient concentrations show significant negative relationships with increased distance from N-source (p<0.05). In heavily trafficked sites of GCNP, atmospheric nitrogen oxides (NOx) were 65% lower at 30m compared to the roadside. Likewise, on the Paria, NOx were 54% lower at 50km compared to 25km from NGS (p<0.01; R2 =0.87, for GCNP and the Paria, respectively). In GCNP, soil δ15N, and pinyon needle δ15N decrease significantly 30m from the roadside (18%, F= 4.07, p<0.05; 40%, F=4.34, p<0.05). On the Paria Plateau, soil δ15N, C:N ratios, and pinyon specific needle area (cm2/g) correlate with decreasing N deposition with distance from NGS (R2 = 0.15; 0.33; 0.17, respectively). Nutrient metrics from selected bioindicators suggest that studied ecosystems closer to N-source display early signs of N saturation. These results will inform programs to develop regulations that target specific sources and depositional loads of N deposition, and support efforts to protect biodiversity and air quality standards for the southwestern U.S.

Sources of nitrogen and phosphorus emissions to Irish rivers and coastal waters: Estimates from a nutrient load apportionment framework.

PubMed

Mockler, Eva M; Deakin, Jenny; Archbold, Marie; Gill, Laurence; Daly, Donal; Bruen, Michael

2017-12-01

More than half of surface water bodies in Europe are at less than good ecological status according to Water Framework Directive assessments, and diffuse pollution from agriculture remains a major, but not the only, cause of this poor performance. Agri-environmental policy and land management practices have, in many areas, reduced nutrient emissions to water. However, additional measures may be required in Ireland to further decouple the relationship between agricultural productivity and emissions to water, which is of vital importance given on-going agricultural intensification. The Source Load Apportionment Model (SLAM) framework characterises sources of phosphorus (P) and nitrogen (N) emissions to water at a range of scales from sub-catchment to national. The SLAM synthesises land use and physical characteristics to predict emissions from point (wastewater, industry discharges and septic tank systems) and diffuse sources (agriculture, forestry, etc.). The predicted annual nutrient emissions were assessed against monitoring data for 16 major river catchments covering 50% of the area of Ireland. At national scale, results indicate that total average annual emissions to surface water in Ireland are over 2700tyr -1 of P and 82,000tyr -1 of N. The proportional contributions from individual sources show that the main sources of P are from municipal wastewater treatment plants and agriculture, with wide variations across the country related to local anthropogenic pressures and the hydrogeological setting. Agriculture is the main source of N emissions to water across all regions of Ireland. These policy-relevant results synthesised large amounts of information in order to identify the dominant sources of nutrients at regional and local scales, contributing to the national nutrient risk assessment of Irish water bodies. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Comparison of Habitat-Specific Nutrient Removal and Release in Pacific NW Salt Marshes at Multiple Spatial Scales

EPA Science Inventory

Wetlands can be sources, sinks and transformers of nutrients, although it is their role in nutrient removal that is valued as a water purification ecosystem service. In order to quantify that service for any wetland, it is important to understand the drivers of nutrient removal w...

Fluvial fluxes of water, suspended particulate matter, and nutrients and potential impacts on tropical coastal water Biogeochemistry: Oahu, Hawai'i

USGS Publications Warehouse

Hoover, D.J.; MacKenzie, F.T.

2009-01-01

Baseflow and storm runoff fluxes of water, suspended particulate matter (SPM), and nutrients (N and P) were assessed in conservation, urban, and agricultural streams discharging to coastal waters around the tropical island of Oahu, Hawai'i. Despite unusually low storm frequency and intensity during the study, storms accounted for 8-77% (median 30%) of discharge, 57-99% (median 93%) of SPM fluxes, 11-79% (median 36%) of dissolved nutrient fluxes and 52-99% (median 85%) of particulate nutrient fluxes to coastal waters. Fluvial nutrient concentrations varied with hydrologic conditions and land use; land use also affected water and particulate fluxes at some sites. Reactive dissolved N:P ratios typically were ???16 (the 'Redfield ratio' for marine phytoplankton), indicating that inputs could support new production by coastal phytoplankton, but uptake of dissolved nutrients is probably inefficient due to rapid dilution and export of fluvial dissolved inputs. Particulate N and P fluxes were similar to or larger than dissolved fluxes at all sites (median 49% of total nitrogen, range 22-82%; median 69% of total phosphorus, range 49-93%). Impacts of particulate nutrients on coastal ecosystems will depend on how efficiently SPM is retained in nearshore areas, and on the timing and degree of transformation to reactive dissolved forms. Nevertheless, the magnitude of particulate nutrient fluxes suggests that they represent a significant nutrient source for many coastal ecosystems over relatively long time scales (weeks-years), and that reductions in particulate nutrient loading actually may have negative impacts on some coastal ecosystems.

Seasonal variation in nutrient retention during inundation of a short-hydroperiod floodplain

USGS Publications Warehouse

Noe, G.B.; Hupp, C.R.

2007-01-01

Floodplains are generally considered to be important locations for nutrient retention or inorganic-to-organic nutrient conversions in riverine ecosystems. However, little is known about nutrient processing in short-hydroperiod floodplains or seasonal variation in floodplain nutrient retention. Therefore, we quantified the net uptake, release or transformation of nitrogen (N), phosphorus (P) and suspended sediment species during brief periods (1-2 days) of overbank flooding through a 250-m floodplain flowpath on the fourth-order Mattawoman Creek, Maryland U.S.A. Sampling occurred during a winter, two spring and a summer flood in this largely forested watershed with low nutrient and sediment loading. Concentrations of NO3- increased significantly in surface water flowing over the floodplain in three of the four floods, suggesting the floodplain was a source of NO3-. The upper portion of the floodplain flowpath consistently exported NH4+, most likely due to the hyporheic: flushing of floodplain soil NH4+, which was then likely nitrified to NO3- in floodwaters. The floodplain was a sink for particulate organic P (POP) during two floods and particulate organic N and inorganic suspended sediment (ISS) during one flood. Large releases of all dissolved inorganic N and P species occurred following a snowmelt and subsequent cold winter flood. Although there was little consistency in most patterns of nutrient processing among the different floods, this floodplain, characterized by brief inundation, low residence time and low nutrient loading, behaved oppositely from the conceptual model for most floodplains in that it generally exported inorganic nutrients and imported organic nutrients.

Stanley Corrsin Award Talk: Fluid Mechanics of Fungi and Slime

NASA Astrophysics Data System (ADS)

Brenner, Michael

2013-11-01

There are interesting fluid mechanics problems everywhere, even in the most lowly and hidden corners of forest floors. Here I discuss some questions we have been working on in recent years involving fungi and slime. A critical issue for the ecology of fungi and slime is nutrient availability: nutrient sources are highly heterogeneous, and strategies are necessary to find food when it runs out. In the fungal phylum Ascomycota, spore dispersal is the primary mechanism for finding new food sources. The defining feature of this phylum is the ascus, a fluid filled sac from which spores are ejected, through a build up in osmotic pressure. We outline the (largely fluid mechanical) design constraints on this ejection strategy, and demonstrate how it provides strong constraints for the diverse morphologies of spores and asci found in nature. The core of the argument revisits a classical problem in elastohydrodynamic lubrication from a different perspective. A completely different strategy for finding new nutrient is found by slime molds and fungi that stretch out - as a single organism- over enormous areas (up to hectares) over forest floors. As a model problem we study the slime mold Physarum polycephalum, which forages with a large network of connected tubes on the forest floors. Localized regions in the network find nutrient sources and then pump the nutrients throughout the entire organism. We discuss fluid mechanical mechanisms for coordinating this transport, which generalize peristalsis to pumping in a heterogeneous network. We give a preliminary discussion to how physarum can detect a nutrient source and pump the nutrient throughout the organism.

Delivery and Establishing Slow Release Carbon Source to the Hanford Vadose Zone Using Colloidal Silica Suspension Injection and Subsequent Gelation - Laboratory Study

NASA Astrophysics Data System (ADS)

Zhong, L.; Lee, M. H.; Lee, B.; Yang, S.

2016-12-01

Delivery of nutrient to and establish a slow release carbon source in the vadose zone and capillary fringe zone is essential for setting up of a long-lasting bioremediation of contaminations in those zones. Conventional solution-based injection and infiltration approaches are facing challenges to achieve the delivery and remedial goals. Aqueous silica suspensions undergo a delayed gelation process under favorite geochemical conditions. The delay in gelation provides a time window for the injection of the suspension into the subsurface; and the gelation of the amendment-silica suspension enables the amendment-laden gel to stay in the target zone and slowly release the constituents for contaminant remediation. This approach can potentially be applied to deliver bio-nutrients to the vadose zone and capillary fringe zone for enhanced bioremediation and achieve remedial goals. This research was conducted to demonstrate delayed gelation of colloidal silica suspensions when carbon sources were added and to prove the gelation occurs in sediments under vadose conditions. Sodium lactate, vegetable oil, ethanol, and molasses were tested as the examples of carbon source (or nutrient) amendments. The rheological properties of the silica suspensions during the gelation were characterized. The influence of silica, salinity, nutrient concentrations, and the type of nutrients was studied. The kinetics of nutrient release from silica-nutrient gel was quantified using molasses as the example, and the influence of suspension gelation time was evaluated. The injection behavior of the suspensions was investigated by monitoring their viscosity changes and the injection pressures when the suspensions were delivered into sediment columns.

Soluble dust as source of nutrients to the oceans and the role of humans

NASA Astrophysics Data System (ADS)

Tsigaridis, K.; Kanakidou, M.; Myriokefalitakis, S.; Nikolaou, P.; Daskalakis, N.; Theodosi, C.; Nenes, A.; Mihalopoulos, N.

2014-12-01

Atmospheric deposition of trace constituents, both of natural and anthropogenic origin, can act as a nutrient source into the open ocean and affect marine ecosystem functioning and subsequently the exchange of CO2 between the atmosphere and the global ocean. Dust is known as a major source of nutrients (Fe and P) into the atmosphere, but only a fraction of these nutrients is released in soluble form that can be assimilated by the ecosystems. Dust is also known to enhance N deposition by interacting with anthropogenic pollutants and neutralisation of part of the acidity of the atmosphere by crustal alkaline species. The link between the soluble iron (Fe) and phosphorus (P) atmospheric deposition and atmospheric acidity, as well as anthropogenic sources, is investigated. The global atmospheric Fe, P and N cycle are parameterized in the global 3-D chemical transport model TM4-ECPL. Both primary emissions of total and soluble Fe and P associated with dust and combustion processes are taken into account, as well as inorganic and organic N emissions. The impact of atmospheric acidity on nutrient solubility is parameterised based on experimental findings. The model results are evaluated by comparison with available observations. The impact of air-quality changes on soluble nutrient deposition is studied by performing sensitivity simulations using preindustrial, present and future emission scenarios. The response of the chemical composition of nutrient-containing aerosols to environmental changes is demonstrated and quantified. This work has been supported by ARISTEIA - PANOPLY grant co-financed by European Union (ESF) and Greek national funds NSRF.

Effect of high fibre diets formulated with different fibrous ingredients on performance, nutrient digestibility and faecal microbiota of weaned piglets.

PubMed

Yu, Cangyou; Zhang, Shihai; Yang, Qing; Peng, Qian; Zhu, Jinlong; Zeng, Xiangfang; Qiao, Shiyan

2016-08-01

The aim of the experiment on 180 weaned piglets (8.9 kg body weight) was to investigate the influence of high fibre diets formulated with different fibrous ingredients on performance, nutrient digestibility, diarrhoea incidence and numbers of faecal microbiota. The dietary treatments included a Control diet and five high fibre diets formulated with different fibre sources including wheat bran, soybean hulls, naked oat hulls, palm kernel expeller and bamboo fibre. The high fibre diets averaged 14.6% neutral detergent fibre with different non-starch polysaccharides (NSP) components and were fed ad libitum for 28 d. Faecal samples were collected during the last 3 d of the experiment and the apparent total tract digestibility of nutrients and fibre components were determined. Pigs fed the Control and wheat bran diets had a higher (p ≤ 0.05) average daily gain (ADG) than pigs fed the palm kernel expeller and bamboo meal diets. The reduced ADG for pigs appeared to be related to reductions in the digestibility of gross energy and dry matter, respectively. The feed-to-gain ratio was significantly higher (p ≤ 0.05) for pigs fed the fibre diets. The digestibility of NSP components was different among the treatments. The diarrhoea incidence was not affected by treatments. The abundance of faecal bifidobacteria was significantly higher (p ≤ 0.05) for pigs fed the wheat bran diet than for pigs fed the bamboo meal diet. It was concluded that the diets formulated with different fibre sources when fed to weaned piglets have different effects on pig performance, nutrient digestibility and numbers of faecal microbiota. The wheat bran diet rich in arabinoxylans enabled a better performance than the other tested diets with fibre addition.

BEST MANAGEMENT PRACTICES FOR THE CONTROL OF NUTRIENTS FROM URBAN NONPOINT SOURCES

EPA Science Inventory

While the costs and benefits associated with the point source control of nutrients are relatively well defined, considerable uncertainties remain in the efficiency and long-term costs associated with the best management practices (BMPs) used to redcuce loads from nonpoint and dif...

The Ins and Outs of USDA Nutrient Composition

USDA-ARS?s Scientific Manuscript database

The USDA National Nutrient Database for Standard Reference (SR) is the major source of food composition data in the United States, providing the foundation for most food composition databases in the public and private sectors. Sources of data used in SR include analytical studies, food manufacturer...

Enhancement of microbial 2,4,6-trinitrotoluene transformation with increased toxicity by exogenous nutrient amendment.

PubMed

Liang, Shih-Hsiung; Hsu, Duen-Wei; Lin, Chia-Ying; Kao, Chih-Ming; Huang, Da-Ji; Chien, Chih-Ching; Chen, Ssu-Ching; Tsai, Isheng Jason; Chen, Chien-Cheng

2017-04-01

In this study, the bacterial strain Citrobacter youngae strain E4 was isolated from 2,4,6-trinitrotoluene (TNT)-contaminated soil and used to assess the capacity of TNT transformation with/without exogenous nutrient amendments. C. youngae E4 poorly degraded TNT without an exogenous amino nitrogen source, whereas the addition of an amino nitrogen source considerably increased the efficacy of TNT transformation in a dose-dependent manner. The enhanced TNT transformation of C. youngae E4 was mediated by increased cell growth and up-regulation of TNT nitroreductases, including NemA, NfsA and NfsB. This result indicates that the increase in TNT transformation by C. youngae E4 via nitrogen nutrient stimulation is a cometabolism process. Consistently, TNT transformation was effectively enhanced when C. youngae E4 was subjected to a TNT-contaminated soil slurry in the presence of an exogenous amino nitrogen amendment. Thus, effective enhancement of TNT transformation via the coordinated inoculation of the nutrient-responsive C. youngae E4 and an exogenous nitrogen amendment might be applicable for the remediation of TNT-contaminated soil. Although the TNT transformation was significantly enhanced by C. youngae E4 in concert with biostimulation, the 96-h LC50 value of the TNT transformation product mixture on the aquatic invertebrate Tigriopus japonicas was higher than the LC50 value of TNT alone. Our results suggest that exogenous nutrient amendment can enhance microbial TNT transformation; however, additional detoxification processes may be needed due to the increased toxicity after reduced TNT transformation. Copyright © 2016 Elsevier Inc. All rights reserved.

Nutrient use by three geographic sources of eastern cottonwood

Treesearch

B. G. Blackmon; James B. Baker; D. T. Cooper

1979-01-01

Three geographic sources (Louisiana, Mississippi, and southern Illinois) of 11-year-old eastern cottonwood (Populus deltoides Bartr.) growing in Mississippi, U.S.A., were studied for differences in biomass and nutrient accumulation. The three sources produced about the same biomass (70-80 t/ha (1 short ton = 2000 lb. = 0.907 t; 1 long ton = 2240 lb. = 1.016 t», but the...

Foliar Spray with Vermiwash Modifies the Arbuscular Mycorrhizal Dependency and Nutrient Stoichiometry of Bhut Jolokia (Capsicum assamicum)

PubMed Central

Gupta, Rajeev; Veer, Vijay; Singh, Lokendra; Kalita, Mohan C.

2014-01-01

Vermiwash (VW), a liquid extract obtained from vermicomposting beds, is used as an organic fertilizer for crop plants. The current study investigated the effect of a vermiwash foliar spray on the response of bhut jolokia (Capsicum assamicum) exposed to two different arbuscular mycorrhizal fungi (AMF: Rhizophagus irregularis, RI and G. mosseae, GM) in acidic soil under naturally ventilated greenhouse conditions. The VW spray significantly influenced the growth of plants receiving the dual treatment of AMF+VW. Plant growth was more prominent in the GM+VW treatment group than that in the RI+VW treatment group. The plant-AMF interactions in relation to growth and nutrient requirements were also significantly influenced by the application of VW. Interestingly, the VW treatment appeared to contribute more N to plants when compared to that under the AMF treatment, which led to changes in the C:N:P stoichiometry in plant shoots. Furthermore, the increased potassium dependency, as observed in the case of the dual treatments, suggests the significance of such treatments for improving crop conditions under salt stress. Overall, our study shows that the VW foliar spray modifies the response of a crop to inoculations of different AMF with regard to growth and nutrient utilization, which has implications for the selection of an efficient combination of nutrient source for improving crop growth. PMID:24651577

Carbon and nitrogen stable isotope analysis of three types of oyster tissue in an impacted estuary

NASA Astrophysics Data System (ADS)

Piola, Richard F.; Moore, Stephanie K.; Suthers, Iain M.

2006-01-01

The stable isotope ratios of carbon ( δ13C) and nitrogen ( δ15N) of the muscle, ctenidia and viscera of the Sydney rock oyster, Saccostrea glomerata, showed the dilution and assimilation of tertiary treated sewage along an estuarine gradient. The enriched 15N values of oyster ctenidia and viscera from within 50 m of the sewage outfall indicated the use of 15N-enriched tertiary treated sewage effluent (16 ± 2.3‰) as a nutrient source. The effect of sewage nitrogen on oyster δ15N was localised, with oysters 5 km upstream and downstream of the outfall not significantly enriched. Viscera δ15N was most sensitive to sewage nutrients and δ13C significantly defined an ocean-to-estuarine gradient. High variance in isotope ratios of viscera compromised its use as an indicator of anthropogenic nutrients, and this also reduced the utility of whole-body stable isotope ratios. Ctenidia was the most useful indicator tissue of sewage discharge at the scale of this study, being consistently and significantly enriched in δ15N close to the sewage outfall and δ13C clearly defined an estuarine gradient with less internal variability than viscera. Muscle δ15N was least sensitive to sewage effluent and showed the least variability, making it more suited to investigations of anthropogenic nutrient enrichment over larger spatio-temporal scales.

Hydrological and biogeochemical variation of stemflow from live, stressed, and dead codominant deciduous canopy trees

NASA Astrophysics Data System (ADS)

Frost, E. E.; Levia, D. F.

2011-12-01

Stemflow, a critical localized point source of both water and nutrients in forested ecosystems, was examined as a function of species and mortality in a mid-Atlantic deciduous forest. Thirty trees across two species, Fagus grandifolia [American beech] and Liriodendron tulipifera [yellow poplar], and three mortality classes, live, stressed, and dead, were sampled and analyzed on an event basis for one year. Significant interspecific differences in volume and nutrient content of stemflow were found that were attributable to differences in canopy structure between the species. Funneling ratios across all three mortality classes were significantly different for F. grandifolia and between dead and live/stressed classes for L. tulipifera. Stemflow volumes from the dead trees of both species were a fraction of that from live and stressed trees. This was attributable to increased relative water storage capacities, canopy crown position, and the lack of surface area contributing to stemflow generation in upper canopy. Concentrations of nutrients in stemflow from dead trees were significantly higher than those found in both live and stressed stems for most nutrients analyzed. Enrichment ratios from dead stems were generally lower given the reduced volumes observed. Given the multi-decadal impact of standing dead trees in forest ecosystems and the uncertainty of changes in morality patterns in forests, additional research is warranted to further quantify the hydrobiochemical impact of stemflow from dying stems over their entire lifecycle.

Certain Grain Foods Can Be Meaningful Contributors to Nutrient Density in the Diets of U.S. Children and Adolescents: Data from the National Health and Nutrition Examination Survey, 2009-2012.

PubMed

Papanikolaou, Yanni; Fulgoni, Victor L

2017-02-20

Grain foods may play an important role in delivering nutrients to the diet of children and adolescents. The present study determined grain food sources of energy/nutrients in U.S. children and adolescents using data from the National Health and Nutrition Examination Survey, 2009-2012. Analyses of grain food sources were conducted using a 24-h recall in participants 2-18 years old ( N = 6109). Sources of nutrients contained in grain foods were determined using U.S. Department of Agriculture nutrient composition databases and excluded mixed dishes. Mean energy and nutrient intakes from the total diet and from various grain foods were adjusted for the sample design using appropriate weights. All grains provided 14% ± 0.2% kcal/day (263 ± 5 kcal/day), 22.5% ± 0.3% (3 ± 0.1 g/day) dietary fiber, 39.3% ± 0.5% (238 ± 7 dietary folate equivalents (DFE)/day) folate and 34.9% ± 0.5% (5.6 ± 0.1 mg/day) iron in the total diet in children and adolescents. The current analyses showed that certain grain foods, in particular breads, rolls and tortillas, ready-to-eat cereals and quick breads and bread products, are meaningful contributors of folate, iron, thiamin, niacin and dietary fiber, a nutrient of public health concern as outlined by the 2015-2020 Dietary Guidelines for Americans. Thus, specific grain foods contribute to nutrient density and have the potential to increase the consumption of several under-consumed nutrients in children and adolescents.

Water Quality Protection from Nutrient Pollution: Case ...

EPA Pesticide Factsheets

Water bodies and coastal areas around the world are threatened by increases in upstream sediment and nutrient loads, which influence drinking water sources, aquatic species, and other ecologic functions and services of streams, lakes, and coastal water bodies. For example, increased nutrient fluxes from the Mississippi River Basin have been linked to increased occurrences of seasonal hypoxia in northern Gulf of Mexico. Lake Erie is another example where in the summer of 2014 nutrients, nutrients, particularly phosphorus, washed from fertilized farms, cattle feedlots, and leaky septic systems; caused a severe algae bloom, much of it poisonous; and resulted in the loss of drinking water for a half-million residents. Our current management strategies for point and non-point source nutrient loadings need to be improved to protect and meet the expected increased future demands of water for consumption, recreation, and ecological integrity. This presentation introduces management practices being implemented and their effectiveness in reducing nutrient loss from agricultural fields, a case analysis of nutrient pollution of the Grand Lake St. Marys and possible remedies, and ongoing work on watershed modeling to improve our understanding on nutrient loss and water quality. Presented at the 3rd International Conference on Water Resource and Environment.

Comparison of Different Methods for Separation of Haploid Embryo Induced through Irradiated Pollen and Their Economic Analysis in Melon (Cucumis melo var. inodorus)

PubMed Central

Baktemur, Gökhan; Taşkın, Hatıra; Büyükalaca, Saadet

2013-01-01

Irradiated pollen technique is the most successful haploidization technique within Cucurbitaceae. After harvesting of fruits pollinated with irradiated pollen, classical method called as “inspecting the seeds one by one” is used to find haploid embryos in the seeds. In this study, different methods were used to extract the embryos more easily, quickly, economically, and effectively. “Inspecting the seeds one by one” was used as control treatment. Other four methods tested were “sowing seeds direct nutrient media,” “inspecting seeds in the light source,” “floating seeds on liquid media,” and “floating seeds on liquid media after surface sterilization.” Y2 and Y3 melon genotypes selected from the third backcross population of Yuva were used as plant material. Results of this study show that there is no statistically significant difference among methods “inspecting the seeds one by one,” “sowing seeds direct CP nutrient media,” and “inspecting seeds in the light source,” although the average number of embryos per fruit is slightly different. No embryo production was obtained from liquid culture because of infection. When considered together with labor costs and time required for embryo rescue, the best methods were “sowing seeds directly in the CP nutrient media“ and ”inspecting seeds in the light source.” PMID:23818825

Application of the ReNuMa model in the Sha He river watershed: tools for watershed environmental management.

PubMed

Sha, Jian; Liu, Min; Wang, Dong; Swaney, Dennis P; Wang, Yuqiu

2013-07-30

Models and related analytical methods are critical tools for use in modern watershed management. A modeling approach for quantifying the source apportionment of dissolved nitrogen (DN) and associated tools for examining the sensitivity and uncertainty of the model estimates were assessed for the Sha He River (SHR) watershed in China. The Regional Nutrient Management model (ReNuMa) was used to infer the primary sources of DN in the SHR watershed. This model is based on the Generalized Watershed Loading Functions (GWLF) and the Net Anthropogenic Nutrient Input (NANI) framework, modified to improve the characterization of subsurface hydrology and septic system loads. Hydrochemical processes of the SHR watershed, including streamflow, DN load fluxes, and corresponding DN concentration responses, were simulated following calibrations against observations of streamflow and DN fluxes. Uncertainty analyses were conducted with a Monte Carlo analysis to vary model parameters for assessing the associated variations in model outputs. The model performed accurately at the watershed scale and provided estimates of monthly streamflows and nutrient loads as well as DN source apportionments. The simulations identified the dominant contribution of agricultural land use and significant monthly variations. These results provide valuable support for science-based watershed management decisions and indicate the utility of ReNuMa for such applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

The phosphorus problem

USDA-ARS?s Scientific Manuscript database

Knowing your nutrients is the key to sustainable farming. Organic sources of crop nutrients or biofertilizers are essential for farming but excess nutrients are damaging for many natural ecosystems and, as such, knowledge and strategies to ensure their judicious use are crucial. Current analytical...

Effects of agricultural biodiversity and seasonal rain on dietary adequacy and household food security in rural areas of Kenya.

PubMed

M'Kaibi, Florence K; Steyn, Nelia P; Ochola, Sophie; Du Plessis, Lisanne

2015-04-25

Kenya has a high prevalence of underweight and stunting in children. It is believed that both agricultural biodiversity and seasonal rainfall influences household food security and dietary intake. In the present study we aimed to study the effects of agricultural biodiversity and seasonal rains on dietary adequacy and household food security of preschool Kenyan children, and to identify significant relationships between these variables. Two cross-sectional studies were undertaken in resource-poor households in rural Kenya approximately 6 months apart. Interviews were done with mothers/caregivers to collect data from randomly selected households (N = 525). A repeated 24-hour recall was used to calculate dietary intake in each phase while household food security was measured using the Household Food Insecurity Access Scale (HFIAS). A nutrient adequacy ratio (NAR) was calculated for each nutrient as the percent of the nutrient meeting the recommended nutrient intake (RNI) for that nutrient. A mean adequacy ratio (MAR) was calculated as the mean of the NARs. Agricultural biodiversity was calculated for each household by counting the number of different crops and animals eaten either from domestic sources or from the wild. Dietary intake was low with the majority of households not meeting the RNIs for many nutrients. However intake of energy (p < 0.001), protein (p < 0.01), iron (p < 0.01), zinc (p < 0.05), calcium (p < 0.05), and folate (p < 0.01) improved significantly from the dry to the rainy season. Household food security also increased significantly (p < 0.001) from the dry (13.1 SD 6.91) to the rainy season (10.9 SD 7.42). Agricultural biodiversity was low with a total of 26 items; 23 domesticated and 3 from the natural habitat. Agricultural biodiversity was positively and significantly related to all NARs (Spearman, p < 0.05) and MAR (Spearman, p < 0.001) indicating a significant positive relationship between agricultural biodiversity of the household with dietary adequacy of the child's diet. Important significant relationships were found in this study: between agricultural biodiversity and dietary adequacy; between agricultural biodiversity and household food security and between dietary adequacy and household food security. Furthermore, the effect of seasonality on household food security and nutrient intake was illustrated.

Monitoring Stream Nutrient Concentration Trends in a Mixed-Land-Use Watershed

NASA Astrophysics Data System (ADS)

Zeiger, S. J.; Hubbart, J. A.

2014-12-01

Mixed-land use watersheds are often a complex patchwork of forested, agricultural, and urban land-uses where differential land-use mediated non-point source pollution can significantly impact water quality. Stream nitrogen and phosphorus concentrations serve as important variables for quantifying land use effects on non-point source pollution in receiving waters and relative impacts on aquatic biota. The Hinkson Creek Watershed (HCW) is a representative mixed land use urbanizing catchment (231 km2) located in central Missouri, USA. A nested-scale experimental watershed study including five permanent hydroclimate stations was established in 2009 to provide quantitative understanding of multiple land use impacts on nutrient loading. Spectrophotometric analysis was used to quantify total inorganic nitrogen (TIN) and total phosphorus (TP as PO4) regimes. Results (2010 - 2013) indicate average nitrate (NO3-) concentration (mg/l) range of 0.28 to 0.46 mg/l, nitrite (NO2-) range of 0.02 to 0.03 mg/l, ammonia (NH3) ranged from 0.04 to 0.08 mg/l, and TP range of 0.26 to 0.39 mg/l. With n=858, NO3-, NO2-, NH3, and TP concentrations were significantly (CI=95%, p=0.00) higher in the subbasin with the greatest percent cumulative agricultural land use (57%). NH3 and TP concentrations were significantly (CI=95%, p=0.00) higher (with the exception of the agricultural subbasin) in the subbasin with the greatest percent cumulative urban land use (26%). Results from multiple regression analyses showed percent cumulative agricultural and urban land uses accounted for 85% and 96% of the explained variance in TIN loading (CI=95%, p=0.08) and TP loading (CI=95%, p=0.02), respectively, between gauging sites. These results improve understanding of agricultural and urban land use impacts on nutrient concentrations in mixed use watersheds of the Midwest and have implications for nutrient reduction programs in the Mississippi River Basin and hypoxia reductions in the Gulf of Mexico, USA.

Decomposition of Phragmites australis rhizomes in artificial land-water transitional zones (ALWTZs) and management implications

NASA Astrophysics Data System (ADS)

Han, Zhen; Cui, Baoshan; Zhang, Yongtao

2015-09-01

Rhizomes are essential organs for growth and expansion of Phragmites australis. They function as an important source of organic matter and as a nutrient source, especially in the artificial land-water transitional zones (ALWTZs) of shallow lakes. In this study, decomposition experiments on 1- to 6-year-old P. australis rhizomes were conducted in the ALWTZ of Lake Baiyangdian to evaluate the contribution of the rhizomes to organic matter accumulation and nutrient release. Mass loss and changes in nutrient content were measured after 3, 7, 15, 30, 60, 90, 120, and 180 days. The decomposition process was modeled with a composite exponential model. The Pearson correlation analysis was used to analyze the relationships between mass loss and litter quality factors. A multiple stepwise regression model was utilized to determine the dominant factors that affect mass loss. Results showed that the decomposition rates in water were significantly higher than those in soil for 1- to 6-year-old rhizomes. However, the sequence of decomposition rates was identical in both water and soil. Significant relationships between mass loss and litter quality factors were observed at a later stage, and P-related factors proved to have a more significant impact than N-related factors on mass loss. According to multiple stepwise models, the C/P ratio was found to be the dominant factor affecting the mass loss in water, and the C/N and C/P ratios were the main factors affecting the mass loss in soil. The combined effects of harvesting, ditch broadening, and control of water depth should be considered for lake administrators.

COUPLING BETWEEN THE COASTAL OCEAN AND YAQUINA BAY, OREGON: THE IMPORTANCE OF OCEANIC INPUTS RELATIVE TO OTHER NITROGEN SOURCES

EPA Science Inventory

Understanding of the role of oceanic input in nutrient loadings is important for understanding nutrient and phytoplankton dynamics in estuaries adjacent to coastal upwelling regions as well as determining the natural background conditions. We examined the nitrogen sources to Yaqu...

Farmed Fish: A source of lipid soluble nutrients

USDA-ARS?s Scientific Manuscript database

The consumption of seafood (fish, molluscs, crustaceans) is associated with a number of positive health outcomes as a result of nutrient content (e,g, protein, n3 fatty acids, vitamin D). Aquacultural “farmed” sources of marine and freshwater seafood total nearly 50% of total seafood production. Gi...

Effects Of Nutrient Source And Supply On Crude Oil Biodegradation In Continuous-Flow Beach Microcosms

EPA Science Inventory

Ammonium and nitrate were used as nitrogen sources to support microbial biodegradation of crude oil in continuous-flow beach microcosms to determine whether either nutrient was more effective in open systems, such as intertidal shorelines. No differences in the rate or the exten...

Nutrient acquisition strategies of mammalian cells.

PubMed

Palm, Wilhelm; Thompson, Craig B

2017-06-07

Mammalian cells are surrounded by diverse nutrients, such as glucose, amino acids, various macromolecules and micronutrients, which they can import through transmembrane transporters and endolysosomal pathways. By using different nutrient sources, cells gain metabolic flexibility to survive periods of starvation. Quiescent cells take up sufficient nutrients to sustain homeostasis. However, proliferating cells depend on growth-factor-induced increases in nutrient uptake to support biomass formation. Here, we review cellular nutrient acquisition strategies and their regulation by growth factors and cell-intrinsic nutrient sensors. We also discuss how oncogenes and tumour suppressors promote nutrient uptake and thereby support the survival and growth of cancer cells.

Nitrate, ascorbic acid, mineral and antioxidant activities of Cosmos caudatus in response to organic and mineral-based fertilizer rates.

PubMed

Hassan, Siti Aishah; Mijin, Salumiah; Yusoff, Umi Kalsom; Ding, Phebe; Wahab, Puteri Edaroyati Megat

2012-06-28

The source and quantity of nutrients available to plants can affect the quality of leafy herbs. A study was conducted to compare quality of Cosmos caudatus in response to rates of organic and mineral-based fertilizers. Organic based fertilizer GOBI (8% N:8% P₂O₅:8% K₂O) and inorganic fertilizer (15% N, 15% P₂O₅, 15% K₂O) were evaluated based on N element rates at 0, 30, 60, 90, 120 kg h⁻¹. Application of organic based fertilizer reduced nitrate, improved vitamin C, antioxidant activity as well as nitrogen and calcium nutrients content. Antioxidant activity and chlorophyll content were significantly higher with increased fertilizer application. Fertilization appeared to enhance vitamin C content, however for the maximum ascorbic acid content, regardless of fertilizer sources, plants did not require high amounts of fertilizer.

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

Hettiarachchi, Ganga M.; Donner, Erica; Doelsch, Emmanuel

To understand the biogeochemistry of nutrients and contaminants in environmental media, their speciation and behavior under different conditions and at multiple scales must be determined. Synchrotron radiation-based X-ray techniques allow scientists to elucidate the underlying mechanisms responsible for nutrient and contaminant mobility, bioavailability, and behavior. The continuous improvement of synchrotron light sources and X-ray beamlines around the world has led to a profound transformation in the field of environmental biogeochemistry and, subsequently, to significant scientific breakthroughs. Following this introductory paper, this special collection includes 10 papers that either present targeted reviews of recent advancements in spectroscopic methods that are applicablemore » to environmental biogeochemistry or describe original research studies conducted on complex environmental samples that have been significantly enhanced by incorporating synchrotron radiation-based X-ray technique(s). We believe that the current focus on improving the speciation of ultra-dilute elements in environmental media through the ongoing optimization of synchrotron technologies (e.g., brighter light sources, improved monochromators, more efficient detectors) will help to significantly push back the frontiers of environmental biogeochemistry research. As many of the relevant techniques produce extremely large datasets, we also identify ongoing improvements in data processing and analysis (e.g., software improvements and harmonization of analytical methods) as a significant requirement for environmental biogeochemists to maximize the information that can be gained using these powerful tools.« less

A comparison of drainage basin nutrient inputs with instream nutrient loads for seven rivers in Georgia and Florida, 1986-90

USGS Publications Warehouse

Asbury, C.E.; Oaksford, E.T.

1997-01-01

Instream nutrient loads of the Altamaha, Suwannee, St. Johns, Satilla, Ogeechee, Withlacoochee, and Ochlockonee River Basins were computed and compared with nutrient inputs for each basin for the period 1986-90. Nutrient constituents that were considered included nitrate, ammonia, organic nitrogen, and total phosphorus. Sources of nutrients considered for this analysis included atmospheric deposition, fertilizer, animal waste, wastewater-treatment plant discharge, and septic discharge. The mean nitrogen input ranged from 2,400 kilograms per year per square kilometer (kg/yr)km2 in the Withlacoochee River Basin to 5,470 (kg/yr)km2 in the Altamaha River Basin. The Satilla and Ochlockonee River Basins also had large amounts of nitrogen input per unit area, totaling 5,430 and 4,920 (kg/yr)km2, respectively.Fertilizer or animal waste, as sources of nitrogen, predominated in all basins. Atmospheric deposition contributed less than one-fourth of the mean total nitrogen input to all basins and was consistently the third largest input in all but the Ogeechee River Basin, where it was the second largest.The mean total phosphorus input ranged from 331 (kg/yr)km2 in the Withlacoochee River Basin to 1,380 (kg/yr)km2 in both the Altamaha and Satilla River Basins. The Ochlockonee River Basin had a phosphorus input of 1,140 (kg/yr)km2.Per unit area, the Suwannee River discharged the highest instream mean total nitrogen and phosphorus loads and also discharged higher instream nitrate loads per unit area than the other six rivers. Phosphorus loads in stream discharge were highest in the Suwannee and Ochlockonee Rivers.The ratio of nutrient outputs to inputs for the seven studied rivers ranged from 4.2 to 14.9 percent, with the St. Johns (14.9 percent) and Suwannee (12.1 percent) Rivers having significantly higher percentages than those from the other basins. The output/input percentages for mean total phosphorus ranged from 1.0 to 7.0 percent, with the St. Johns (6.2 percent) and Suwannee (7.0 percent) Rivers exporting the highest percentage of phosphorus.Although instream nutrient loads constitute only one of the various pathways nutrients may take in leaving a river basin, only a relatively small part of nutrient input to the basin leaves the basin in stream discharge for the major coastal rivers examined in this study. The actual amount of nutrient transported in a river basin depends on the ways in which nutrients are physically handled, geographically distributed, and chemically assimilated within a river basin.

Cation Uptake and Allocation by Red Pine Seedlings under Cation-Nutrient Stress in a Column Growth Experiment

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

Shi, Zhenqing; Balogh-Brunstad, Zsuzsanna; Grant, Michael R.

Background and Aims Plant nutrient uptake is affected by environmental stress, but how plants respond to cation-nutrient stress is poorly understood. We assessed the impact of varying degrees of cation-nutrient limitation on cation uptake in an experimental plant-mineral system. Methods Column experiments, with red pine (Pinus resinosa Ait.) seedlings growing in sand/mineral mixtures, were conducted for up to nine months under a range of Ca- and K-limited conditions. The Ca and K were supplied from both minerals and nutrient solutions with varying Ca and K concentrations. Results Cation nutrient stress had little impact on carbon allocation after nine months ofmore » plant growth and K was the limiting nutrient for biomass production. The Ca/Sr and K/Rb ratio results allowed independent estimation of dissolution incongruency and discrimination against Sr and Rb during cation uptake processes. The fraction of K in biomass from biotite increased with decreasing K supply from nutrient solutions. The mineral anorthite was consistently the major source of Ca, regardless of nutrient treatment. Conclusions Red pine seedlings exploited more mineral K in response to more severe K deficiency. This did not occur for Ca. Plant discrimination factors must be carefully considered to accurately identify nutrient sources using cation tracers.« less

Inputs and internal cycling of nitrogen to a causeway influenced, hypersaline lake, Great Salt Lake, Utah, USA

USGS Publications Warehouse

Naftz, David L.

2017-01-01

Nitrogen inputs to Great Salt Lake (GSL), located in the western USA, were quantified relative to the resident nitrogen mass in order to better determine numeric nutrient criteria that may be considered at some point in the future. Total dissolved nitrogen inputs from four surface-water sources entering GSL were modeled during the 5-year study period (2010–2014) and ranged from 1.90 × 106 to 5.56 × 106 kg/year. The railroad causeway breach was a significant conduit for the export of dissolved nitrogen from Gilbert to Gunnison Bay, and in 2011 and 2012, net losses of total nitrogen mass from Gilbert Bay via the Causeway breach were 9.59 × 105 and 1.51 × 106 kg. Atmospheric deposition (wet + dry) was a significant source of nitrogen to Gilbert Bay, exceeding the dissolved nitrogen load contributed via the Farmington Bay causeway surface-water input by >100,000 kg during 2 years of the study. Closure of two railroad causeway culverts in 2012 and 2013 likely initiated a decreasing trend in the volume of the higher density Deep Brine Layer and associated declines in total dissolved nitrogen mass contained in this layer. The large dissolved nitrogen pool in Gilbert Bay relative to the amount of nitrogen contributed by surface-water inflow sources is consistent with the terminal nature of GSL and the predominance of internal nutrient cycling. The opening of the new railroad causeway breach in 2016 will likely facilitate more efficient bidirectional flow between Gilbert and Gunnison Bays, resulting in potentially substantial changes in nutrient pools within GSL.

The carbon storage regulator (Csr) system exerts a nutrient-specific control over central metabolism in Escherichia coli strain Nissle 1917.

PubMed

Revelles, Olga; Millard, Pierre; Nougayrède, Jean-Philippe; Dobrindt, Ulrich; Oswald, Eric; Létisse, Fabien; Portais, Jean-Charles

2013-01-01

The role of the post-transcriptional carbon storage regulator (Csr) system in nutrient utilization and in the control of the central metabolism in E. coli reference commensal strain Nissle 1917 was investigated. Analysis of the growth capabilities of mutants altered for various components of the Csr system (csrA51, csrB, csrC and csrD mutations) showed that only the protein CsrA - the key component of the system - exerts a marked role in carbon nutrition. Attenuation of CsrA activity in the csrA51 mutant affects the growth efficiency on a broad range of physiologically relevant carbon sources, including compounds utilized by the Entner-Doudoroff (ED) pathway. Detailed investigations of the metabolomes and fluxomes of mutants and wild-type cells grown on carbon sources representative of glycolysis and of the ED pathway (glucose and gluconate, respectively), revealed significant re-adjusting of central carbon metabolism for both compounds in the csrA51 mutant. However, the metabolic re-adjusting observed on gluconate was strikingly different from that observed on glucose, indicating a nutrient-specific control of metabolism by the Csr system.

The Carbon Storage Regulator (Csr) System Exerts a Nutrient-Specific Control over Central Metabolism in Escherichia coli Strain Nissle 1917

PubMed Central

Nougayrède, Jean-Philippe; Dobrindt, Ulrich; Oswald, Eric; Létisse, Fabien; Portais, Jean-Charles

2013-01-01

The role of the post-transcriptional carbon storage regulator (Csr) system in nutrient utilization and in the control of the central metabolism in E. coli reference commensal strain Nissle 1917 was investigated. Analysis of the growth capabilities of mutants altered for various components of the Csr system (csrA51, csrB, csrC and csrD mutations) showed that only the protein CsrA - the key component of the system - exerts a marked role in carbon nutrition. Attenuation of CsrA activity in the csrA51 mutant affects the growth efficiency on a broad range of physiologically relevant carbon sources, including compounds utilized by the Entner-Doudoroff (ED) pathway. Detailed investigations of the metabolomes and fluxomes of mutants and wild-type cells grown on carbon sources representative of glycolysis and of the ED pathway (glucose and gluconate, respectively), revealed significant re-adjusting of central carbon metabolism for both compounds in the csrA51 mutant. However, the metabolic re-adjusting observed on gluconate was strikingly different from that observed on glucose, indicating a nutrient-specific control of metabolism by the Csr system. PMID:23840455

Scenario analysis of the impacts of socioeconomic development on phosphorous export and loading from the Dongting Lake watershed, China.

PubMed

Hou, Ying; Chen, Weiping; Liao, Yuehua; Luo, Yueping

2017-12-01

Socioeconomic development in lake watersheds is closely related with lake nutrient pollution. As the second largest freshwater lake in China, the Dongting Lake has been experiencing an increase in nutrient loading and a growing risk of eutrophication. This study aimed to reveal the likely impacts of the socioeconomic development of the Dongting Lake watershed on the phosphorous pollution in the lake. We estimated the contributions from different sources and sub-watersheds to the total phosphorous (TP) export and loading from the Dongting Lake watershed under two most likely socioeconomic development scenarios. Moreover, we predicted the likely permissible and actual TP loadings to the Dongting Lake. Under both two scenarios, three secondary sub-watersheds-the upper and lower reaches of the Xiang River watershed and the Dongting Lake Area-are expected to dominate the contribution to the TP export from the Dongting Lake watershed in 2020. Three primary sub-watersheds-the Dongting Lake Area, the Xiang River, and the Yuan River watersheds-are predicted to be the major contributors to the TP loading from the entire watershed. The two scenarios are expected to have a slight difference in TP export and lake TP loading. Livestock husbandry is expected to be the predominant anthropogenic TP source in each of the sub-watersheds under both scenarios. Compared to 2010, permissible TP loading is not expected to increase but actual TP loading is predicted to grow significantly in 2020. Our study provides methodologies to identify the key sources and regions of lake nutrient loading from watersheds with complex socioeconomic context, and to reveal the potential influences of socioeconomic development on nutrient pollution in lake watersheds.

Solving Nutrient Loading in the Great Lakes: An Integrative, Interdisciplinary and Ambidextrous Approach

NASA Astrophysics Data System (ADS)

Borrello, M. C.; Keeton, T.; Foley, T.; Frost, A.; Green, N.; Isler, J.

2014-12-01

Environmental impacts from industrialized agriculture have been studied extensively over the past two decades. Degradation of surface water occurs, primarily as a result of nutrient loading, causing algal blooms in streams and lakes. Discovery of the toxin microcystin in Lake Erie, a drinking water source for some municipalities, has been associated with agricultural runoff and created a new awareness in the general public. This study used data gathered over ten years by local residents, high school students and undergraduates on surface water around the Lower Peninsula of Michigan to test a simple correlation of nutrients (soluble reactive phosphorus and nitrogen ammonia) along with the presence of specific antibiotics and antibiotic resistance to identify dominant sources of nutrient loading in the Lake Huron Watershed. Data gathering came from multiple sources and were processed by faculty and students at an undergraduate, liberal arts institution. College students from various disciplines worked with community members and municipalities in an effort to describe the problem. Students proposed solutions which by-passed relatively inactive regulatory agencies to create an integrative, interactive resolution that involved a surprisingly wide extent of the community. Addressing cultural norms beginning with those most affected by a degraded environment has reaped some success in changing behavior and moving towards a sustainable solution. The research conducted and supervised by undergraduate students has significance in the broader, professional area of geochemistry, environmental health and sustainable agriculture. That fact plays an important role in how the students see themselves in the process and what motivated them to: 1. Choose to participate in the research in the first place, 2. Reach out to the broader community (scientific and regional) to carry out their research and 3. Pursue solutions beyond the classroom and summer research experience.

Comparison of Habitat-Specific Nutrient Removal and Release in Pacific NW Salt Marshes at Multiple Spatial Scales - CERF

EPA Science Inventory

Wetlands can be sources, sinks and transformers of nutrients, although it is their role in nutrient removal that is valued as a water purification ecosystem service. In order to quantify that service for any wetland, it is important to understand the drivers of nutrient removal w...

Comparison of Nutrient Drivers and Response Metrics in Oregon Estuaries

EPA Science Inventory

With the goal of assessing sensitivity to nutrient enrichment, we present a cross-estuary comparison of nutrient sources, levels, and biological responses (phytoplankton and macroalgae) for thirteen Oregon estuaries. Nitrogen levels in the upstream portions of the estuaries are ...

Nutrients and Narragansett Bay

EPA Science Inventory

Narragansett Bay has been heavily fertilized by anthropogenic nutrients for almost 120 years. This presentation discusses the first introductions of human sources of nutrients to the Bay, via sewage and urban runoff, in the late 1890s through to the recent reductions in sewage ef...

Marine nutrient contributions to tidal creeks in Virginia: spawning marine fish as nutrient vectors to freshwater ecosystems

NASA Astrophysics Data System (ADS)

Macavoy, S. E.; Garman, G. C.

2006-12-01

Coastal freshwater streams are typically viewed as conduits for the transport of sediment and nutrients to the coasts. Some coastal streams however experience seasonal migrations of anadromous fish returning to the freshwater to spawn. The fish may be vectors for the delivery of marine nutrients to nutrient poor freshwater in the form of excreted waste and post-spawning carcasses. Nutrients derived from marine sources are 13C, 15N and 34S enriched relative to nutrients in freshwater. Here we examine sediment, particulate organic matter (POM), invertebrates and fish in two tidal freshwater tributaries of the James River USA. The d15N of POM became elevated (from 3.8 to 6.5%), coincident with the arrival of anadromous river herring (Alosa sp), indicating a pulse of marine nitrogen. However, the elevated 15N was not observed in sediment samples or among invertebrates, which did not experience a seasonal isotopic shift (there were significant differences however among the guilds of invertebrate). Anadromous Alosa aestivalis captured within the tidal freshwater were 13C and 34S enriched (-19.3 and 17.2%, respectively) relative to resident freshwater fishes (-26.4 and 3.6% respectively) captured within 2 weeks of the Alosa. Although it is likely that marine derived nitrogen was detected in the tidal freshwater, it was not in sufficient abundance to change the isotope signature of most ecosystem components.

Identification of marine-derived lipids in juvenile coho salmon and aquatic insects through fatty acid analysis

USGS Publications Warehouse

Heintz, Ron A.; Wipfli, Mark S.; Hudson, John P.

2010-01-01

The energetic benefits enjoyed by consumers in streams with salmon runs depend on how those benefits are accrued. Adult Pacific salmon Oncorhynchus spp. deliver significant amounts of nutrients (i.e., nitrogen and phosphorus) and carbon to streams when they spawn and die; these nutrient additions can have demonstrable effects on primary production in streams. Consumption of carcass tissues or eggs provides for direct energy subsidies to consumers and may have significant effects on their condition. In this study, comparisons of juvenile coho salmon O. kisutch and aquatic insects exposed to terrestrial and marine energy sources demonstrated that direct consumption of marine-derived lipids had a significant effect on the lipid reserves of consumers. Direct consumption of marine-derived tissues was verified through fatty acid analysis. Selected aquatic insects and juvenile coho salmon were reared for 6 weeks in experimental streams supplied with terrestrial or marine energy sources. Chironomid midges, nemourid stoneflies, and juvenile coho salmon exposed to the marine energy source altered their fatty acid compositions by incorporating the long-chain polyunsaturated fatty acids that are characteristic of marine fish. The fatty acid composition of baetid mayflies was unaffected. The direct movement of specific fatty markers indicated that direct consumption of marine-derived tissues led to increased energy reserves (triacylglycerols) in consumers. Similar results were obtained for juvenile coho salmon sampled from natural streams before and after the arrival of adult salmon runs. These data indicate that marine-derived lipids from anadromous fish runs are an important source of reserve lipids for consumers that overwinter in streams.

Relation of watershed setting and stream nutrient yields at selected sites in central and eastern North Carolina, 1997-2008

USGS Publications Warehouse

Harden, Stephen L.; Cuffney, Thomas F.; Terziotti, Silvia; Kolb, Katharine R.

2013-01-01

Data collected between 1997 and 2008 at 48 stream sites were used to characterize relations between watershed settings and stream nutrient yields throughout central and eastern North Carolina. The focus of the investigation was to identify environmental variables in watersheds that influence nutrient export for supporting the development and prioritization of management strategies for restoring nutrient-impaired streams. Nutrient concentration data and streamflow data compiled for the 1997 to 2008 study period were used to compute stream yields of nitrate, total nitrogen (N), and total phosphorus (P) for each study site. Compiled environmental data (including variables for land cover, hydrologic soil groups, base-flow index, streams, wastewater treatment facilities, and concentrated animal feeding operations) were used to characterize the watershed settings for the study sites. Data for the environmental variables were analyzed in combination with the stream nutrient yields to explore relations based on watershed characteristics and to evaluate whether particular variables were useful indicators of watersheds having relatively higher or lower potential for exporting nutrients. Data evaluations included an examination of median annual nutrient yields based on a watershed land-use classification scheme developed as part of the study. An initial examination of the data indicated that the highest median annual nutrient yields occurred at both agricultural and urban sites, especially for urban sites having large percentages of point-source flow contributions to the streams. The results of statistical testing identified significant differences in annual nutrient yields when sites were analyzed on the basis of watershed land-use category. When statistical differences in median annual yields were noted, the results for nitrate, total N, and total P were similar in that highly urbanized watersheds (greater than 30 percent developed land use) and (or) watersheds with greater than 10 percent point-source flow contributions to streamflow had higher yields relative to undeveloped watersheds (having less than 10 and 15 percent developed and agricultural land uses, respectively) and watersheds with relatively low agricultural land use (between 15 and 30 percent). The statistical tests further indicated that the median annual yields for total P were statistically higher for watersheds with high agricultural land use (greater than 30 percent) compared to the undeveloped watersheds and watersheds with low agricultural land use. The total P yields also were higher for watersheds with low urban land use (between 10 and 30 percent developed land) compared to the undeveloped watersheds. The study data indicate that grouping and examining stream nutrient yields based on the land-use classifications used in this report can be useful for characterizing relations between watershed settings and nutrient yields in streams located throughout central and eastern North Carolina. Compiled study data also were analyzed with four regression tree models as a means of determining which watershed environmental variables or combination of variables result in basins that are likely to have high or low nutrient yields. The regression tree analyses indicated that some of the environmental variables examined in this study were useful for predicting yields of nitrate, total N, and total P. When the median annual nutrient yields for all 48 sites were evaluated as a group (Model 1), annual point-source flow yields had the greatest influence on nitrate and total N yields observed in streams, and annual streamflow yields had the greatest influence on yields of total P. The Model 1 results indicated that watersheds with higher annual point-source flow yields had higher annual yields of nitrate and total N, and watersheds with higher annual streamflow yields had higher annual yields of total P. When sites with high point-source flows (greater than 10 percent of total streamflow) were excluded from the regression tree analyses (Models 2–4), the percentage of forested land in the watersheds was identified as the primary environmental variable influencing stream yields for both total N and total P. Models 2, 3 and 4 did not identify any watershed environmental variables that could adequately explain the observed variability in the nitrate yields among the set of sites examined by each of these models. The results for Models 2, 3, and 4 indicated that watersheds with higher percentages of forested land had lower annual total N and total P yields compared to watersheds with lower percentages of forested land, which had higher median annual total N and total P yields. Additional environmental variables determined to further influence the stream nutrient yields included median annual percentage of point-source flow contributions to the streams, variables of land cover (percentage of forested land, agricultural land, and (or) forested land plus wetlands) in the watershed and (or) in the stream buffer, and drainage area. The regression tree models can serve as a tool for relating differences in select watershed attributes to differences in stream yields of nitrate, total N, and total P, which can provide beneficial information for improving nutrient management in streams throughout North Carolina and for reducing nutrient loads to coastal waters.

Groundwater nutrient concentrations near an incised midwestern stream: Effects of floodplain lithology and land management

USGS Publications Warehouse

Schilling, K.E.; Jacobson, P.

2008-01-01

It has been recognized that subsurface lithology plays an important role in controlling nutrient cycling and transport in riparian zones. In Iowa and adjacent states, the majority of alluvium preserved in small and moderate sized valleys consists of Holocene-age organic-rich, and fine-grained loam. In this paper, we describe and evaluate spatial and temporal patterns of lithology and groundwater nutrient concentrations at a riparian well transect across Walnut Creek at the Neal Smith National Wildlife Refuge in Jasper County, Iowa. Land treatment on one side of the stream reduced the grass cover to bare ground and allowed assessment of the effects of land management on nutrient concentrations. Results indicated that groundwater in Holocene alluvium is very nutrient rich with background concentrations of nitrogen, phosphorus and dissolved organic carbon that exceed many environmentally sensitive criteria. Average concentrations of ammonium exceeded 1 mg/l in several wells under grass cover whereas nitrate concentrations exceeded 20 mg/l in wells under bare ground. Phosphate concentrations ranged from 0.1 to 1.3 mg/l and DOC concentrations exceeded 5 mg/l in many wells. Denitrification, channel incision, land management and geologic age of alluvium were found to contribute to variable nutrient loading patterns at the site. Study results indicated that riparian zones of incised streams downcutting through nutrient-rich Holocene alluvium can potentially be a significant source of nutrient loadings to streams. ?? 2008 Springer Science+Business Media B.V.

Nutrient mass balance and trends, Mobile River Basin, Alabama, Georgia, and Mississippi

USGS Publications Warehouse

Harned, D.A.; Atkins, J.B.; Harvill, J.S.

2004-01-01

A nutrient mass balance - accounting for nutrient inputs from atmospheric deposition, fertilizer, crop nitrogen fixation, and point source effluents; and nutrient outputs, including crop harvest and storage - was calculated for 18 subbasins in the Mobile River Basin, and trends (1970 to 1997) were evaluated as part of the U.S. Geological Survey National Water Quality Assessment (NAWQA) Program. Agricultural nonpoint nitrogen and phosphorus sources and urban nonpoint nitrogen sources are the most important factors associated with nutrients in this system. More than 30 percent of nitrogen yield in two basins and phosphorus yield in eight basins can be attributed to urban point source nutrient inputs. The total nitrogen yield (1.3 tons per square mile per year) for the Tombigbee River, which drains a greater percentage of agricultural (row crop) land use, was larger than the total nitrogen yield (0.99 tons per square mile per year) for the Alabama River. Decreasing trends of total nitrogen concentrations in the Tombigbee and Alabama Rivers indicate that a reduction occurred from 1975 to 1997 in the nitrogen contributions to Mobile Bay from the Mobile River. Nitrogen concentrations also decreased (1980 to 1995) in the Black Warrior River, one of the major tributaries to the Tombigbee River. Total phosphorus concentrations increased from 1970 to 1996 at three urban influenced sites on the Etowah River in Georgia. Multiple regression analysis indicates a distinct association between water quality in the streams of the Mobile River drainage basin and agricultural activities in the basin.

Nutrient processes at the stream-lake interface for a channelized versus unmodified stream mouth

USGS Publications Warehouse

Niswonger, Richard G.; Naranjo, Ramon C.; Smith, David; Constantz, James E.; Allander, Kip K.; Rosenberry, Donald O.; Neilson, Bethany; Rosen, Michael R.; Stonestrom, David A.

2017-01-01

Inorganic forms of nitrogen and phosphorous impact freshwater lakes by stimulating primary production and affecting water quality and ecosystem health. Communities around the world are motivated to sustain and restore freshwater resources and are interested in processes controlling nutrient inputs. We studied the environment where streams flow into lakes, referred to as the stream-lake interface (SLI), for a channelized and unmodified stream outlet. Channelization is done to protect infrastructure or recreational beach areas. We collected hydraulic and nutrient data for surface water and shallow groundwater in two SLIs to develop conceptual models that describe characteristics that are representative of these hydrologic features. Water, heat, and solute transport models were used to evaluate hydrologic conceptualizations and estimate mean residence times of water in the sediment. A nutrient mass balance model is developed to estimate net rates of adsorption and desorption, mineralization, and nitrification along subsurface flow paths. Results indicate that SLIs are dynamic sources of nutrients to lakes and that the common practice of channelizing the stream at the SLI decreases nutrient concentrations in pore water discharging along the lakeshore. This is in contrast to the unmodified SLI that forms a barrier beach that disconnects the stream from the lake and results in higher nutrient concentrations in pore water discharging to the lake. These results are significant because nutrient delivery through pore water seepage at the lakebed from the natural SLI contributes to nearshore algal communities and produces elevated concentrations of inorganic nutrients in the benthic zone where attached algae grow.

Modeling nutrient retention at the watershed scale: Does small stream research apply to the whole river network?

NASA Astrophysics Data System (ADS)

Aguilera, Rosana; Marcé, Rafael; Sabater, Sergi

2013-06-01

are conveyed from terrestrial and upstream sources through drainage networks. Streams and rivers contribute to regulate the material exported downstream by means of transformation, storage, and removal of nutrients. It has been recently suggested that the efficiency of process rates relative to available nutrient concentration in streams eventually declines, following an efficiency loss (EL) dynamics. However, most of these predictions are based at the reach scale in pristine streams, failing to describe the role of entire river networks. Models provide the means to study nutrient cycling from the stream network perspective via upscaling to the watershed the key mechanisms occurring at the reach scale. We applied a hybrid process-based and statistical model (SPARROW, Spatially Referenced Regression on Watershed Attributes) as a heuristic approach to describe in-stream nutrient processes in a highly impaired, high stream order watershed (the Llobregat River Basin, NE Spain). The in-stream decay specifications of the model were modified to include a partial saturation effect in uptake efficiency (expressed as a power law) and better capture biological nutrient retention in river systems under high anthropogenic stress. The stream decay coefficients were statistically significant in both nitrate and phosphate models, indicating the potential role of in-stream processing in limiting nutrient export. However, the EL concept did not reliably describe the patterns of nutrient uptake efficiency for the concentration gradient and streamflow values found in the Llobregat River basin, posing in doubt its complete applicability to explain nutrient retention processes in stream networks comprising highly impaired rivers.

Subterranean Groundwater Nutrient Input to Coastal Oceans and Coral Reef Sustainability

NASA Astrophysics Data System (ADS)

Paytan, A.; Street, J. H.

2003-12-01

Coral reefs are often referred to as the tropical rain forests of the oceans because of their high productivity and biodiversity. Recent observations in coral reefs worldwide have shown clear degradation in water quality and coral reef health and diversity. The implications of this are severe, including tremendous economic losses mostly though fishing and tourism. Nutrient loading has been implicated as one possible cause for the ecosystem decline. A previously unappreciated potential source of nutrient loading is submarine ground water discharge (SGW). Ground water in many cases has high nutrient content from sewage pollution and fertilizer application for agriculture and landscaping. To better understand the effect of this potential source of nutrient input and degrading water quality, we are exploring the contribution of SGW to the nutrient levels in coral reefs. A key to this approach is determining the amount and source of SGW that flows into the coast as well as its nutrient concentrations. The SGW flux and associated input of chemical dissolved load (nutrient, DOC, trace elements and other contaminants) is quantified using naturally occurring Ra isotopes. Radium isotopes have been shown to be excellent tracers for SGW inputs into estuaries and coastal areas (Moore, 1996; Hussain et al., 1999; Kerst et al., 2000). Measurements of Ra activity within the coral reef, the lagoons and the open waters adjacent to the reef provide valuable information regarding the input of Ra as well as nutrients and possibly pollutant from groundwater discharge. Through this analysis the effect of SGD on the delicate carbon and nutrient balance of the fragile coral reef ecosystem could be evaluated. In addition to quantifying the contribution of freshwater to the nutrient mass balance in the reef, information regarding the length of time a water parcel has remained in the near-shore region over the reef can be estimated using the Ra isotope quartet.

The nutritional adequacy of a limited vegan diet for a Controlled Ecological Life-Support System.

PubMed

Saha, P R; Trumbo, P R

1996-01-01

Purdue University, as well as the Johnson and Kennedy Space Centers and NASA Ames Research Center, are investigating approximately 5-10 plants that will be grown hydroponically to provide not only the energy and nutrients, but also the oxygen for humans habitating in Mars and lunar bases. The growth and nutritional status of rats fed either a control diet (adequate in all macro- and micronutrients) or a strict vegetarian diet consisting of 5 (vegan-5) or 10 (vegan-10) candidate crop species were investigated. In addition, vegan-10 diets were supplemented with mineral and/or vitamin mix at a level similar to the control diets to assess the effect of supplementation on nutrient status. The assessment of inedible plant material as an alternative food source was also investigated. Results of this study demonstrated that consumption of the vegan-10 diet significantly improved weight gain of rats compared to that for rats fed the vegan-5 diet. Mineral supplementation, at a level present in the control diet, to the vegan-10 diet improved growth and nutrient status, but growth was significantly lower compared to the control-fed rats. Inclusion of inedible plant material, high in ash content, improved some indices of nutrient status, without improving growth.

The nutritional adequacy of a limited vegan diet for a Controlled Ecological Life-Support System

NASA Technical Reports Server (NTRS)

Saha, P. R.; Trumbo, P. R.; Mitchell, C. A. (Principal Investigator)

1996-01-01

Purdue University, as well as the Johnson and Kennedy Space Centers and NASA Ames Research Center, are investigating approximately 5-10 plants that will be grown hydroponically to provide not only the energy and nutrients, but also the oxygen for humans habitating in Mars and lunar bases. The growth and nutritional status of rats fed either a control diet (adequate in all macro- and micronutrients) or a strict vegetarian diet consisting of 5 (vegan-5) or 10 (vegan-10) candidate crop species were investigated. In addition, vegan-10 diets were supplemented with mineral and/or vitamin mix at a level similar to the control diets to assess the effect of supplementation on nutrient status. The assessment of inedible plant material as an alternative food source was also investigated. Results of this study demonstrated that consumption of the vegan-10 diet significantly improved weight gain of rats compared to that for rats fed the vegan-5 diet. Mineral supplementation, at a level present in the control diet, to the vegan-10 diet improved growth and nutrient status, but growth was significantly lower compared to the control-fed rats. Inclusion of inedible plant material, high in ash content, improved some indices of nutrient status, without improving growth.

The nutritional adequacy of a limited vegan diet for a controlled ecological life-support system

NASA Astrophysics Data System (ADS)

Saha, P. R.; Trumbo, P. R.

Purdue University, as well as the Johnson and Kennedy Space Centers and NASA Ames Research Center, are investigating approximately 5-10 plants that will be grown hydroponically to provide not only the energy and nutrients, but also the oxygen for humans habitating in Mars and lunar bases. The growth and nutritional status of rats fed either a control diet (adequate in all macro- and micronutrients) or a strict vegetarian diet consisting of 5 (vegan-5) or 10 (vegan-10) candidate crop species were investigated. In addition, vegan-10 diets were supplemented with mineral and/or vitamin mix at a level similar to the control diets to assess the effect of supplementation on nutrient status. The assessment of inedible plant material as an alternative food source was also investigated. Results of this study demonstrated that consumption of the vegan-10 diet significantly improved weight gain of rats compared to that for rats fed the vegan-5 diet. Mineral supplementation, at a level present in the control diet, to the vegan-10 diet improved growth and nutrient status, but growth was significantly lower compared to the control-fed rats. Inclusion of inedible plant material, high in ash content, improved some indices of nutrient status, without improving growth.

A hydrologic network supporting spatially referenced regression modeling in the Chesapeake Bay watershed

USGS Publications Warehouse

Brakebill, J.W.; Preston, S.D.

2003-01-01

The U.S. Geological Survey has developed a methodology for statistically relating nutrient sources and land-surface characteristics to nutrient loads of streams. The methodology is referred to as SPAtially Referenced Regressions On Watershed attributes (SPARROW), and relates measured stream nutrient loads to nutrient sources using nonlinear statistical regression models. A spatially detailed digital hydrologic network of stream reaches, stream-reach characteristics such as mean streamflow, water velocity, reach length, and travel time, and their associated watersheds supports the regression models. This network serves as the primary framework for spatially referencing potential nutrient source information such as atmospheric deposition, septic systems, point-sources, land use, land cover, and agricultural sources and land-surface characteristics such as land use, land cover, average-annual precipitation and temperature, slope, and soil permeability. In the Chesapeake Bay watershed that covers parts of Delaware, Maryland, Pennsylvania, New York, Virginia, West Virginia, and Washington D.C., SPARROW was used to generate models estimating loads of total nitrogen and total phosphorus representing 1987 and 1992 land-surface conditions. The 1987 models used a hydrologic network derived from an enhanced version of the U.S. Environmental Protection Agency's digital River Reach File, and course resolution Digital Elevation Models (DEMs). A new hydrologic network was created to support the 1992 models by generating stream reaches representing surface-water pathways defined by flow direction and flow accumulation algorithms from higher resolution DEMs. On a reach-by-reach basis, stream reach characteristics essential to the modeling were transferred to the newly generated pathways or reaches from the enhanced River Reach File used to support the 1987 models. To complete the new network, watersheds for each reach were generated using the direction of surface-water flow derived from the DEMs. This network improves upon existing digital stream data by increasing the level of spatial detail and providing consistency between the reach locations and topography. The hydrologic network also aids in illustrating the spatial patterns of predicted nutrient loads and sources contributed locally to each stream, and the percentages of nutrient load that reach Chesapeake Bay.

Hindcasting of nutrient loadings from its catchment on a highly valuable coastal lagoon: the example of the Fleet, Dorset, UK, 1866–2004

PubMed Central

Weber, Geraint J; O'Sullivan, Patrick E; Brassley, Paul

2006-01-01

Background Nutrient loadings from its catchment upon The Fleet, a highly valuable coastal lagoon in Southern England, were hindcast for the period AD 1866–2004, using a catchment model, export coefficients, and historical data on land use changes, livestock numbers, and human population. Agriculture was the main nutrient source throughout, other inputs representing minor contributions. Permanent pasture was historically the main land use, with temporary grassland and cereals increasing during the mid-20th century. Sheep, the main 19th century livestock, were replaced by cattle during the 1930s. Results Total nitrogen loadings rose from ca 41 t yr-1 during the late 19th century to 49–54 t yr-1 for the mid-20th, increasing to 98 t yr-1 by 1986. Current values are ca 77 t yr-1. Total phosphorus loads increased from ca 0.75 t yr-1 for the late 19th century to ca 1.6 t yr-1 for the mid-20th, reached ca 2.2 t yr-1 in 1986, and are now ca 1.5 t yr-1. Loadings rose most rapidly between 1946 and 1988, owing to increased use of inorganic fertilisers, and rising sheep and cattle numbers. Livestock were the main nutrient source throughout, but inputs from inorganic fertilisers increased after 1946, peaking in 1986. Sewage treatment works and other sources contribute little nitrogen, but ca 35% of total phosphorus. Abbotsbury Swannery, an ancient Mute Swan community, provides ca 0.5% of total nitrogen, and ca 5% of total phosphorus inputs. Conclusion The Fleet has been grossly overloaded with nitrogen since 1866, climaxing during the 1980s. Total phosphorus inputs lay below 'permissible' limits until the 1980s, exceeding them in inner, less tidal parts of the lagoon, during the 1940s. Loadings on Abbotsbury Bay exceeded 'permissible' limits by the 1860s, becoming 'dangerous' during the mid-20th century. Phosphorus stripping at point sources will not significantly reduce loadings to all parts of the lagoon. Installation of 5 m buffer strips throughout the catchment and shoreline will marginally affect nitrogen loadings, but will reduce phosphorus inputs to the West Fleet below 'permissible' limits. Only a combination of measures will significantly affect Abbotsbury Bay, where, without effluent diversion, loadings will remain beyond 'permissible'. PMID:17196108

Shifting the Arctic Carbon Balance: Effects of a Long-Term Fertilization Experiment and Anomalously Warm Temperatures on Net Ecosystem Exchange in the Alaskan Tundra

NASA Astrophysics Data System (ADS)

Ludwig, S.; Natali, S.; Rastetter, E. B.; Shaver, G. R.; Graham, L. M.; Jastrow, J. D.

2017-12-01

The arctic is warming at an accelerated rate relative to the globe. Among the predicted consequences of warming temperatures in the arctic are increased gross primary productivity (GPP), ecosystem respiration (ER), and nutrient availability. The net effect of these changes on the carbon (C) cycle and resulting C balance and feedback to climate change remain unclear. Historically the Arctic has been a C sink, but evidence from recent years suggests some regions in the Arctic are becoming C sources. To predict the role of the Arctic in global C cycling, the mechanisms affecting arctic C balances need to be better resolved. We measured net ecosystem exchange (NEE) in a long-term, multi-level, fertilization experiment at Toolik Lake, AK during an anomalously warm summer. We modeled NEE, ER, and GPP using a Bayesian network model. The best-fit model included Q10 temperature functions and linear fertilization functions for both ER and GPP. ER was more strongly affected by temperature and GPP was driven more by fertilization level. As a result, fertilization increased the C sink capacity, but only at moderate and low temperatures. At high temperatures (>28 °C) the NEE modeled for the highest level of fertilization was not significantly different from zero. In contrast, at ambient nutrient levels modeled NEE was significantly below zero (net uptake) until 35 °C, when it becomes neutral. Regardless of the level of fertilization, NEE never decreased with warming. Temperature in low ranges (5-15°C) had no net effect on NEE, whereas NEE began to increase exponentially with temperature after a threshold of 15°C until becoming a net source to the atmosphere at 37°C. Our results indicate that the C sink strength of tundra ecosystems can be increased with small increases in nutrient availability, but that large increase in nutrient availability can switch tundra ecosystems into C sources under warm conditions. Warming temperatures in tundra ecosystems will only decrease C sink strength, and the continued increase in days with anomalously high summer temperatures could lead to the Arctic tundra becoming a source of C and a positive feed back to climate change.

EFFECTS OF AMMONIUM AND NITRATE ON NUTRIENT UPTAKE AND ACTIVITY OF NITROGEN ASSIMILATING ENZYMES IN WESTERN HEMLOCK

EPA Science Inventory

Western hemlock seedlings were grown in nutrient solutions with ammonium, nitrate or ammonium plus nitrate as nitrogen sources. he objectives were to examine (1) possible selectivity for ammonium or nitrate as an N source, (2) the maintenance of charge balance during ammonium and...

Using Stable Isotopes to Assess Connectivity: the Importance of Oceanic and Watershed Nitrogen Sources for Estuarine Primary Producers

EPA Science Inventory

Estuaries located at the interface of terrestrial and oceanic ecosystems receive nutrients from both ecosystems. Stable isotopes of primary producers and consumers are often used as an indicator of nutrient sources. We assembled natural abundance nitrogen stable isotope (δ15N) d...

Water infiltration and surface soil structural properties as influenced by animal traffic in the Southern Piedmont USA

USDA-ARS?s Scientific Manuscript database

Surface-soil structural condition in long-term perennial pastures is expected to be modified by how forage is (a) harvested through haying or grazing and (b) stimulated through source of nutrient application. We determined the effects of harvest management and nutrient source on macropore filling, ...

Certain Grain Foods Can Be Meaningful Contributors to Nutrient Density in the Diets of U.S. Children and Adolescents: Data from the National Health and Nutrition Examination Survey, 2009–2012

PubMed Central

Papanikolaou, Yanni; Fulgoni, Victor L.

2017-01-01

Grain foods may play an important role in delivering nutrients to the diet of children and adolescents. The present study determined grain food sources of energy/nutrients in U.S. children and adolescents using data from the National Health and Nutrition Examination Survey, 2009–2012. Analyses of grain food sources were conducted using a 24-h recall in participants 2–18 years old (N = 6109). Sources of nutrients contained in grain foods were determined using U.S. Department of Agriculture nutrient composition databases and excluded mixed dishes. Mean energy and nutrient intakes from the total diet and from various grain foods were adjusted for the sample design using appropriate weights. All grains provided 14% ± 0.2% kcal/day (263 ± 5 kcal/day), 22.5% ± 0.3% (3 ± 0.1 g/day) dietary fiber, 39.3% ± 0.5% (238 ± 7 dietary folate equivalents (DFE)/day) folate and 34.9% ± 0.5% (5.6 ± 0.1 mg/day) iron in the total diet in children and adolescents. The current analyses showed that certain grain foods, in particular breads, rolls and tortillas, ready-to-eat cereals and quick breads and bread products, are meaningful contributors of folate, iron, thiamin, niacin and dietary fiber, a nutrient of public health concern as outlined by the 2015–2020 Dietary Guidelines for Americans. Thus, specific grain foods contribute to nutrient density and have the potential to increase the consumption of several under-consumed nutrients in children and adolescents. PMID:28230731

Azolla pinnata growth performance in different water sources.

PubMed

Nordiah, B; Harah, Z Muta; Sidik, B Japar; Hazma, W N Wan

2012-07-01

Azolla pinnata R.Br. growth performance experiments in different water sources were conducted from May until July 2011 at Aquaculture Research Station, Puchong, Malaysia. Four types of water sources (waste water, drain water, paddy field water and distilled water) each with different nutrient contents were used to grow and evaluate the growth performance of A. pinnata. Four water sources with different nutrient contents; waste, drain, paddy and distilled water as control were used to evaluate the growth performance of A. pinnata. Generally, irrespective of the types of water sources there were increased in plant biomass from the initial biomass (e.g., after the first week; lowest 25.2% in distilled water to highest 133.3% in drain water) and the corresponding daily growth rate (3.61% in distilled water to 19.04% in drain water). The increased in biomass although fluctuated with time was consistently higher in drain water compared to increased in biomass for other water sources. Of the four water sources, drain water with relatively higher nitrate concentration (0.035 +/- 0.003 mg L(-l)) and nitrite (0.044 +/- 0.005 mg L(-1)) and with the available phosphate (0.032 +/- 0.006 mg L(-1)) initially provided the most favourable conditions for Azolla growth and propagation. Based on BVSTEP analysis (PRIMER v5), the results indicated that a combination of more than one nutrient or multiple nutrient contents explained the observed increased in biomass of A. pinnata grown in the different water sources.

Insect-based protein: future promising protein source for fish cultured

NASA Astrophysics Data System (ADS)

Nugroho, R. A.; Nur, F. M.

2018-04-01

As one of the vital component feed used in fisheries, fishmeal (FM) is generally added to the fish diet to enhance fish growth, digestive performance and absorption of nutrients. This addition contributes significantly to the variable production cost in the aquaculture industry. Expanded production of carnivorous species requiring high protein, high-energy feeds will further tax global fish meal. Thus, research based on the low-cost budget for feed operating cost should be strategized to assist aquaculturists in enhancing fish productivity. Moreover, suitable alternative feed ingredients will have to be utilized to provide the essential nutrients and energy needed to fuel the growth of aquaculture production. To this effect, the use of insect-based protein sources to replace FM that often scarce, expensive, limited availability, and leads to high fish production costs is alternative ways and has been gaining momentum. Currently, Insects have been proposed as one of the potential future protein sources of protein because of the production of insects is highly sustainable. Farming insects is characterized by higher food conversion efficiencies, lower environmental impact, and higher potential to be grown on waste streams.

[Effects of plateau zokor disturbance and restoration years on soil nutrients and microbial functional diversity in alpine meadow].

PubMed

Hu, Lei; Ade, Lu-ji; Zi, Hong-biao; Wang, Chang-ting

2015-09-01

To explore the dynamic process of restoration succession in degraded alpine meadow that had been disturbed by plateau zokors in the eastern Tibetan Plateau, we examined soil nutrients and microbial functional diversity using conventional laboratory analysis and the Biolog-ECO microplate method. Our study showed that: 1) The zokors disturbance significantly reduced soil organic matter, total nitrogen, available nitrogen and phosphorus contents, but had no significant effects on soil total phosphorus and potassium contents; 2) Soil microbial carbon utilization efficiency, values of Shannon, Pielou and McIntosh indexes increased with alpine meadow restoration years; 3) Principal component analysis (PCA) showed that carbohydrates and amino acids were the main carbon sources for maintaining soil microbial community; 4) Redundancy analysis ( RDA) indicated that soil pH, soil organic matter, total nitrogen, available nitrogen, and total potassium were the main factors influencing the metabolic rate of soil microbial community and microbial functional diversity. In summary, variations in soil microbial functional diversity at different recovery stages reflected the microbial response to aboveground vegetation, soil microbial composition and soil nutrients.

Nutrition Source Book.

ERIC Educational Resources Information Center

National Dairy Council, Rosemont, IL.

This booklet presents a nutrient approach to teaching nutrition. It contains basic nutrition information along with suggestions for translating this information to fulfill the needs of families and individuals. Topics discussed are: (1) a nutrient approach to teaching nutrition; (2) functions of nutrients; (3) how food handling affects nutrient…

Seasonal sediment and nutrients transport patterns

USDA-ARS?s Scientific Manuscript database

It is essential to understand sediment and nutrient sources and their spatial and temporal patterns in order to design effective mitigation strategies. However, long-term data sets to determine sediment and nutrient loadings are scarce and expensive to collect. The goal of this study was to determin...

Nutrient bioassimilation capacity of aquacultured oysters: quantification of an ecosystem service.

PubMed

Higgins, Colleen B; Stephenson, Kurt; Brown, Bonnie L

2011-01-01

Like many coastal zones and estuaries, the Chesapeake Bay has been severely degraded by cultural eutrophication. Rising implementation costs and difficulty achieving nutrient reduction goals associated with point and nonpoint sources suggests that approaches supplemental to source reductions may prove useful in the future. Enhanced oyster aquaculture has been suggested as one potential policy initiative to help rid the Bay waters of excess nutrients via harvest of bioassimilated nutrients. To assess this potential, total nitrogen (TN), total phosphorous (TP), and total carbon (TC) content were measured in oyster tissue and shell at two floating-raft cultivation sites in the Chesapeake Bay. Models were developed based on the common market measurement of total length (TL) for aquacultured oysters, which was strongly correlated to the TN (R2 = 0.76), TP (R2 = 0.78), and TC (R2 = 0.76) content per oyster tissue and shell. These models provide resource managers with a tool to quantify net nutrient removal. Based on model estimates, 10(6) harvest-sized oysters (76 mm TL) remove 132 kg TN, 19 kg TP, and 3823 kg TC. In terms of nutrients removed per unit area, oyster harvest is an effective means of nutrient removal compared with other nonpoint source reduction strategies. At a density of 286 oysters m(-2), assuming no mortality, harvest size nutrient removal rates can be as high as 378 kg TN ha(-1), 54 kg TP ha(-1), and 10,934 kg TC ha(-1) for 76-mm oysters. Removing 1 t N from the Bay would require harvesting 7.7 million 76-mm TL cultivated oysters.

Persistence of rock-derived nutrients in the wet tropical forests of La Selva, Costa Rica.

PubMed

Porder, Stephen; Clark, Deborah A; Vitousek, Peter M

2006-03-01

We used strontium isotopes and analysis of foliar and soil nutrients to test whether erosion can rejuvenate the supply of rock-derived nutrients in the lowland tropical rain forest of La Selva, Costa Rica. We expected that these nutrients would be depleted from soils on stable surfaces, a result of over one million years of weathering in situ. In fact, trees and palms in all landscape positions derive a relatively high percentage (> or =40%) of their strontium from bedrock, rather than atmospheric, sources. The fraction that is rock-derived increases on slopes, but with no detectable effect on plant macronutrient concentrations. These results differ from those in a similar ecosystem on Kauai, Hawaii, where plants on uneroded surfaces derive almost all of their foliar Sr from atmospheric, rather than bedrock, sources. The results from La Selva challenge the assumption that tropical Oxisols in general have low nutrient inputs from bedrock, and support the hypothesis that erosion can increase the supply of these nutrients in lower landscape positions.

Diet and Asthma: Vitamins and Methyl Donors

PubMed Central

Han, Yueh-Ying; Blatter, Josh; Brehm, John M.; Forno, Erick; Litonjua, Augusto A; Celedón, Juan C.

2014-01-01

SUMMARY Dietary changes may partly explain the high burden of asthma in industrialized nations. Experimental studies have motivated a significant number of observational studies of the relation between vitamins (A, C, D, and E) or nutrients acting as methyl donors (folate, vitamin B12, and choline) and asthma. Because observational studies are susceptible to several sources of bias, well-conducted randomized controlled trials (RCTs) remain the “gold standard” to determine whether a vitamin or nutrient has an effect on asthma. Evidence from observational studies and/or relatively few RCTs most strongly justify ongoing and future RCTs of: 1) vitamin D to prevent or treat asthma, 2) choline supplementation as adjuvant treatment for asthma, and 3) vitamin E to prevent the detrimental effects of air pollution in subjects with asthma. At this time, there is insufficient evidence to recommend supplementation with any vitamin or nutrient acting as a methyl donor to prevent or treat asthma. PMID:24461761

Rainfall,bulk deposition of nutrients and their seasonal variation in two tropical lowland and montane forests in Borneo

NASA Astrophysics Data System (ADS)

Gomyo, M.; Kuraji, K.; Kitayama, K.; Suzuki, M.

2008-12-01

The Borneo Island, the third largest in the world, is experiencing rapid and extensive changes driven by population growth and economic expansion. This change has induced the tropical forest conversion to other land uses for subsistence cultivations, large-scale mono crop plantations and the irreversible loss of forest biodiversity. In this paper, we examine rainwater chemistry observed at two different national parks in Malaysian Borneo for 12 months. We present annual bulk nutrient input flux and its seasonality, and the results are compared with data obtained at a number of other locations in the tropics. The possible source of the atmospheric nutrients and factors determining the differences of the two sites in Borneo is discussed. Nutrient fluxes in rainfall were measured two times every week in natural tropical montane rain forest in Mount Kinabalu National Park (MK) and natural tropical lowland rain forest in Lambir Hills National Park (LH) in Malaysian Borneo. Annual rainfall in MK and LH were 3,232 and 2,978 mm yr-1 respectively. Three-month rainfall during the northeast monsoon season in LH was 1.6 times greater than that in MK, whereas the 3- month rainfall during the southwest monsoon season in MK was 2.8 times greater than that in LH. The difference of volume-weighed mean ion concentration of nutrients of rainwater between MK and LH is not significant except Mg and Ca. The correlation coefficient between Na and Cl concentration is greater in LH than in MK suggesting that the rainwater chemistry was affected by mainly marine origin in LH both marine and terrestrial origin in MK. From the comparison of annual flux of nutrients in MK and LH with the other sites in the other tropical sites, it was noted that the Na and Cl flux in LH, which is only 13.7 km from the coast, is relatively low compared with the other sites located less than 20 km from the coast. Classification of nutrients was done by cluster analysis of 3-month nutrient flux in MK and LH and the results support the hypothesis of the different origin of nutrients between MK an LH. The source of high Mg and SO4-S flux in LH might be the outcrops of bedrock along the roads which contains high Mg and SO4-S.

Effects of different forms of white lupin (Lupinus albus) grain supplementation on feed intake, digestibility, growth performance and carcass characteristics of Washera sheep fed Rhodes grass (Chloris gayana) hay-based diets.

PubMed

Tefera, Gebru; Tegegne, Firew; Mekuriaw, Yeshambel; Melaku, Solomon; Tsunekawa, Atsushi

2015-12-01

Protein is the major limiting nutrient in feeding ruminants especially in dryland areas. Thus, looking for locally available protein sources such as white lupin (Lupinus albus) grain is commendable. The objective of this experiment was to determine effects of supplementation of different forms of white lupin grain (WLG) on feed and nutrient intake, digestibility, growth and carcass characteristics. Twenty-five yearling male Washera sheep with initial body weight (BW) of 16.26 ± 1.41 kg (mean ± SD) were used. Animals were blocked into five based on their initial BW and were randomly assigned to one of the following five dietary treatments: Rhodes grass (Chloris gayana) hay (RGH) alone (T1) or supplemented with 300 g (on dry matter (DM) basis) raw WLG (T2) or raw soaked and dehulled WLG (T3) or roasted WLG (T4) or raw soaked WLG (T5). Supplementation with WLG significantly improved total DM and nutrient intake (P < 0.001), nutrient digestibility (P < 0.01), and average daily gain (ADG) and feed conversion efficiency (FCE) (P < 0.001). Carcass quality parameters were significantly (P < 0.001) higher for supplemented sheep. However, the difference in carcass quality parameters among supplemented groups was not significant (P > 0.05). It is concluded that roasting white lupin grain can lead to a better feed and nutrient intake and consequently better carcass quality. White lupin grain can be recommended not only for maintenance but also for optimum performance of ruminants.

Diversity and Activity of Diazotrophs in Great Barrier Reef Surface Waters.

PubMed

Messer, Lauren F; Brown, Mark V; Furnas, Miles J; Carney, Richard L; McKinnon, A D; Seymour, Justin R

2017-01-01

Discrepancies between bioavailable nitrogen (N) concentrations and phytoplankton growth rates in the oligotrophic waters of the Great Barrier Reef (GBR) suggest that undetermined N sources must play a significant role in supporting primary productivity. One such source could be biological dinitrogen (N 2 ) fixation through the activity of "diazotrophic" bacterioplankton. Here, we investigated N 2 fixation and diazotroph community composition over 10° S of latitude within GBR surface waters. Qualitative N 2 fixation rates were found to be variable across the GBR but were relatively high in coastal, inner and outer GBR waters, reaching 68 nmol L -1 d -1 . Diazotroph assemblages, identified by amplicon sequencing of the nifH gene, were dominated by the cyanobacterium Trichodesmium erythraeum , γ-proteobacteria from the Gamma A clade, and δ-proteobacterial phylotypes related to sulfate-reducing genera. However, diazotroph communities exhibited significant spatial heterogeneity, correlated with shifts in dissolved inorganic nutrient concentrations. Specifically, heterotrophic diazotrophs generally increased in relative abundance with increasing concentrations of phosphate and N, while Trichodesmium was proportionally more abundant when concentrations of these nutrients were low. This study provides the first in-depth characterization of diazotroph community composition and N 2 fixation dynamics within the oligotrophic, N-limited surface waters of the GBR. Our observations highlight the need to re-evaluate N cycling dynamics within oligotrophic coral reef systems, to include diverse N 2 fixing assemblages as a potentially significant source of dissolved N within the water column.

Fog and Phosphorous:Mist Connections?

NASA Astrophysics Data System (ADS)

Weathers, K. C.; Caraco, N. F.; Ewing, H. A.

2005-12-01

Fog (or cloud) is an important vector for delivering water, nutrients and pollutants to many coastal and montane ecosystems worldwide. Previous research has demonstrated that elements and ions whose sources are thought to be atmospheric, such as nitrogen and sulfur, can be deposited in substantial quantities via fog water deposition. However, the ecologically-important nutrient, phosphorous (P), is thought to derive primarily from guano or terrestrial sources; it has not been demonstrated to be deposited in significant quantities via rain water, for example. Here we suggest that phosphorous may be quite prevalent in fog water and that the atmospheric deposition of phosphorous to the forest floor is significant. Phosphate appears to be either immobilized or utilized in the forest floor. We examine the concentrations of phosphorous in fog water from several ecosystems in the Americas and the spatial patterns of P movement in a fog-dominated, redwood forest in Sonoma County, CA. Phosphate concentrations were surprisingly high, ranging from 0.002 to 2.9 mg/L, in fog samples from near-coast and montane ecosystems. Phosphate in fog water appears to be derived from a crustal source as demonstrated by the strong relationship between phosphorous concentrations in fog and K:Na ratios. Fog water phosphorous inputs to the forest floor were observed to decline exponentially and vary significantly from edge to interior in a redwood forest. Phosphate via fog deposition can be detected in shallow soil zones but not at greater depths, and only at the forest edge, during the summer fog season.

EFFECT OF NITROGEN SOURCE ON THE GROWTH AND TOXICITY OF THREE POTENTIALLY HARMFUL DINOFLAGELLATES

EPA Science Inventory

Increases in population and agriculture in coastal areas can result in increased nutrient inputs and alterations in the ratios of organic to inorganic nutrients in coastal waters. Such changes in coastal nutrient regimes can affect phytoplankton community structure by creating c...

The third National Food Consumption Survey, INRAN-SCAI 2005-06: major dietary sources of nutrients in Italy.

PubMed

Sette, Stefania; Le Donne, Cinzia; Piccinelli, Raffaela; Mistura, Lorenza; Ferrari, Marika; Leclercq, Catherine

2013-12-01

To promote healthy food consumption patterns, information is required on the contribution of food groups to total nutrient intake. The objective of this paper is to identify the main dietary sources of nutrients in the diet of the population in Italy. Data collected through individual food records within the INRAN-SCAI 2005-06 survey were required. The final sample included 3323 subjects aged 0.1-97.7 years. The percentage contributed by each food category to the intake of energy, dietary fibre and of 26 nutrients was calculated. Above 3 years of age, the main contributors to macro- and micro-nutrient intakes were similar among the various age-sex groupings with few exceptions. These data might be used to develop specific strategies for Italy in order to increase the intake of dietary fibre and to decrease that of total fats and of sugars in the population.

Gustatory and metabolic perception of nutrient stress in Drosophila.

PubMed

Linford, Nancy J; Ro, Jennifer; Chung, Brian Y; Pletcher, Scott D

2015-02-24

Sleep loss is an adaptive response to nutrient deprivation that alters behavior to maximize the chances of feeding before imminent death. Organisms must maintain systems for detecting the quality of the food source to resume healthy levels of sleep when the stress is alleviated. We determined that gustatory perception of sweetness is both necessary and sufficient to suppress starvation-induced sleep loss when animals encounter nutrient-poor food sources. We further find that blocking specific dopaminergic neurons phenocopies the absence of gustatory stimulation, suggesting a specific role for these neurons in transducing taste information to sleep centers in the brain. Finally, we show that gustatory perception is required for survival, specifically in a low nutrient environment. Overall, these results demonstrate an important role for gustatory perception when environmental food availability approaches zero and illustrate the interplay between sensory and metabolic perception of nutrient availability in regulating behavioral state.

Estimates of long-term mean-annual nutrient loads considered for use in SPARROW models of the Midcontinental region of Canada and the United States, 2002 base year

USGS Publications Warehouse

Saad, David A.; Benoy, Glenn A.; Robertson, Dale M.

2018-05-11

Streamflow and nutrient concentration data needed to compute nitrogen and phosphorus loads were compiled from Federal, State, Provincial, and local agency databases and also from selected university databases. The nitrogen and phosphorus loads are necessary inputs to Spatially Referenced Regressions on Watershed Attributes (SPARROW) models. SPARROW models are a way to estimate the distribution, sources, and transport of nutrients in streams throughout the Midcontinental region of Canada and the United States. After screening the data, approximately 1,500 sites sampled by 34 agencies were identified as having suitable data for calculating the long-term mean-annual nutrient loads required for SPARROW model calibration. These final sites represent a wide range in watershed sizes, types of nutrient sources, and land-use and watershed characteristics in the Midcontinental region of Canada and the United States.

Quantification of Shallow Groundwater Nutrient Dynamics in Septic Areas

Treesearch

Ying Ouyang; Jia-En Zhang

2012-01-01

Of all groundwater pollution sources, septic systems are the second largest source of groundwater nitrate contamination in USA. This study investigated shallow groundwater (SGW) nutrient dynamics in septic areas at the northern part of the Lower St. Johns River Basin, Florida, USA. Thirty-five SGW-monitoring wells, located at nine different urban areas served by septic...

Water and nutrient budgets for Vancouver Lake, Vancouver, Washington, October 2010-October 2012

USGS Publications Warehouse

Sheibley, Rich W.; Foreman, James R.; Marshall, Cameron A.; Welch, Wendy B.

2014-01-01

Vancouver Lake, a large shallow lake in Clark County, near Vancouver, Washington, has been undergoing water-quality problems for decades. Recently, the biggest concern for the lake are the almost annual harmful cyanobacteria blooms that cause the lake to close for recreation for several weeks each summer. Despite decades of interest in improving the water quality of the lake, fundamental information on the timing and amount of water and nutrients entering and exiting the lake is lacking. In 2010, the U.S. Geological Survey conducted a 2-year field study to quantify water flows and nutrient loads in order to develop water and nutrient budgets for the lake. This report presents monthly and annual water and nutrient budgets from October 2010–October 2012 to identify major sources and sinks of nutrients. Lake River, a tidally influenced tributary to the lake, flows into and out of the lake almost daily and composed the greatest proportion of both the water and nutrient budgets for the lake, often at orders of magnitude greater than any other source. From the water budget, we identified precipitation, evaporation and groundwater inflow as minor components of the lake hydrologic cycle, each contributing 1 percent or less to the total water budget. Nutrient budgets were compiled monthly and annually for total nitrogen, total phosphorus, and orthophosphate; and, nitrogen loads were generally an order of magnitude greater than phosphorus loads across all sources. For total nitrogen, flow from Lake River at Felida, Washington, made up 88 percent of all inputs into the lake. For total phosphorus and orthophosphate, Lake River at Felida flowing into the lake was 91 and 76 percent of total inputs, respectively. Nutrient loads from precipitation and groundwater inflow were 1 percent or less of the total budgets. Nutrient inputs from Burnt Bridge Creek and Flushing Channel composed 12 percent of the total nitrogen budget, 8 percent of the total phosphorus budget, and 21 percent of the orthophosphate budget. We identified several data gaps and areas for future research, which include the need for better understanding nutrient inputs to the lake from sediment resuspension and better quantification of indirect nutrient inputs to the lake from Salmon Creek.

Variation in nutrient-acquisition patterns by mycorrhizal fungi of rare and common orchids explains diversification in a global biodiversity hotspot.

PubMed

Nurfadilah, Siti; Swarts, Nigel D; Dixon, Kingsley W; Lambers, Hans; Merritt, David J

2013-06-01

Many terrestrial orchids have an obligate requirement for mycorrhizal associations to provide nutritional support from germination to establishment. This study will investigate the ability of orchid mycorrhizal fungi (OMF) to utilize a variety of nutrient sources in the nutrient-impoverished (low organic) soils of the Southwest Australian Floristic Region (SWAFR) in order to effectively compete, survive and sustain the orchid host. Mycorrhizal fungi representing key OMF genera were isolated from three common and widespread species: Pterostylis recurva, Caladenia flava and Diuris corymbosa, and one rare and restricted species: Drakaea elastica. The accessibility of specific nutrients was assessed by comparing growth including dry biomass of OMF in vitro on basal CN MMN liquid media. Each of the OMF accessed and effectively utilized a wide variety of nutrient compounds, including carbon (C) sources, inorganic and organic nitrogen (N) and inorganic and organic phosphorus (P). The nutrient compounds utilized varied between the genera of OMF, most notably sources of N. These results suggest that OMF can differentiate between niches (micro-niche specialization) in a constrained, highly resource-limited environment such as the SWAFR. Phosphorus is the most limited macronutrient in SWAFR soils and the ability to access phytate by OMF indicates a characterizing functional capacity of OMF from the SWAFR. Furthermore, compared with OMF isolated from the rare D. elastica, OMF associating with the common P. recurva produced far greater biomass over a wider variety of nutritional sources. This suggests a broader tolerance for habitat variation providing more opportunities for the common orchid for recruitment and establishment at a site.

Nitrogen cycling in canopy soils of tropical montane forests responds rapidly to indirect N and P fertilization.

PubMed

Matson, Amanda L; Corre, Marife D; Veldkamp, Edzo

2014-12-01

Although the canopy can play an important role in forest nutrient cycles, canopy-based processes are often overlooked in studies on nutrient deposition. In areas of nitrogen (N) and phosphorus (P) deposition, canopy soils may retain a significant proportion of atmospheric inputs, and also receive indirect enrichment through root uptake followed by throughfall or recycling of plant litter in the canopy. We measured net and gross rates of N cycling in canopy soils of tropical montane forests along an elevation gradient and assessed indirect effects of elevated nutrient inputs to the forest floor. Net N cycling rates were measured using the buried bag method. Gross N cycling rates were measured using (15) N pool dilution techniques. Measurements took place in the field, in the wet and dry season, using intact cores of canopy soil from three elevations (1000, 2000 and 3000 m). The forest floor had been fertilized biannually with moderate amounts of N and P for 4 years; treatments included control, N, P, and N + P. In control plots, gross rates of NH4 (+) transformations decreased with increasing elevation; gross rates of NO3 (-) transformations did not exhibit a clear elevation trend, but were significantly affected by season. Nutrient-addition effects were different at each elevation, but combined N + P generally increased N cycling rates at all elevations. Results showed that canopy soils could be a significant N source for epiphytes as well as contributing up to 23% of total (canopy + forest floor) mineral N production in our forests. In contrast to theories that canopy soils are decoupled from nutrient cycling in forest floor soil, N cycling in our canopy soils was sensitive to slight changes in forest floor nutrient availability. Long-term atmospheric N and P deposition may lead to increased N cycling, but also increased mineral N losses from the canopy soil system. © 2014 John Wiley & Sons Ltd.

Food Sources of Total Energy and Nutrients among U.S. Infants and Toddlers: National Health and Nutrition Examination Survey 2005-2012.

PubMed

Grimes, Carley A; Szymlek-Gay, Ewa A; Campbell, Karen J; Nicklas, Theresa A

2015-08-14

Understanding the dietary intakes of infants and toddlers is important because early life nutrition influences future health outcomes. The aim of this study was to determine the dietary sources of total energy and 16 nutrients in a nationally representative sample of U.S. infants and toddlers aged 0-24 months. Data from the 2005-2012 National Health and Nutrition Examination Survey were analyzed. Dietary intake was assessed in 2740 subjects using one 24-h dietary recall. The population proportion was used to determine the contribution of foods and beverages to nutrient intakes. Overall infant formulas and baby foods were the leading sources of total energy and nutrients in infants aged 0-11.9 months. In toddlers, the diversity of food groups contributing to nutrient intakes was much greater. Important sources of total energy included milk, 100% juice and grain based mixed dishes. A number of foods of low nutritional quality also contributed to energy intakes including sweet bakery products, sugar-sweetened beverages and savory snacks. Overall non-flavored milks and ready-to-eat cereals were the most important contributors to micronutrient intakes. In conclusion this information can be used to guide parents regarding appropriate food selection as well as inform targeted dietary strategies within public health initiatives to improve the diets of infants and toddlers.

Sources and Delivery of Nutrients to the Northwestern Gulf of Mexico from Streams in the South-Central United States1

PubMed Central

Rebich, Richard A; Houston, Natalie A; Mize, Scott V; Pearson, Daniel K; Ging, Patricia B; Evan Hornig, C

2011-01-01

Abstract SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were developed to estimate nutrient inputs [total nitrogen (TN) and total phosphorus (TP)] to the northwestern part of the Gulf of Mexico from streams in the South-Central United States (U.S.). This area included drainages of the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf hydrologic regions. The models were standardized to reflect nutrient sources and stream conditions during 2002. Model predictions of nutrient loads (mass per time) and yields (mass per area per time) generally were greatest in streams in the eastern part of the region and along reaches near the Texas and Louisiana shoreline. The Mississippi River and Atchafalaya River watersheds, which drain nearly two-thirds of the conterminous U.S., delivered the largest nutrient loads to the Gulf of Mexico, as expected. However, the three largest delivered TN yields were from the Trinity River/Galveston Bay, Calcasieu River, and Aransas River watersheds, while the three largest delivered TP yields were from the Calcasieu River, Mermentau River, and Trinity River/Galveston Bay watersheds. Model output indicated that the three largest sources of nitrogen from the region were atmospheric deposition (42%), commercial fertilizer (20%), and livestock manure (unconfined, 17%). The three largest sources of phosphorus were commercial fertilizer (28%), urban runoff (23%), and livestock manure (confined and unconfined, 23%). PMID:22457582

The nutrient content of US household food purchases by store types

PubMed Central

Stern, Dalia; Ng, Shu Wen; Popkin, Barry M

2015-01-01

Introduction Little is known about where households shop for packaged foods, what foods and beverages they purchase, and the nutrient content of these purchases. The objectives are to describe volume trends and nutrient content (food groups and nutrient profiles) of household packaged foods purchases (PFP) by store-type. Methods Cross-sectional analysis of US households’ food purchases (Nielsen Homescan) from 2000 to 2012 (n=652,023 household-year observations) with survey weights used for national representativeness. Household PFP trends (% volume) by store-type, household purchases of key food and beverage groups based on caloric contribution by store-type, and mean caloric and nutrient densities (sugars, saturated fat and sodium) of household PFP by store-type are analyzed. Data were collected from 2000–2012. Analyses were conducted in 2014–2015. Results The proportion of total volume of household PFP significantly increased from 2000 to 2012 for mass-merchandisers (13.1 to 23.9%), convenience-stores (3.6 to 5.9%) and warehouse-club (6.2 to 9.8%), and significantly decreased for grocery-chains (58.5 to 46.3%) and non-chain grocerys (10.3 to 5.2%). Top common sources of calories (%) from household PFP by food/beverage group include: savory snacks, grain-based desserts and regular soft-drinks. The energy, total sugar, sodium and saturated fat densities of household PFP from mass-merchandisers, warehouse-club and convenience-stores were higher, compared to grocery-stores. Conclusions PFP from stores with poorer nutrient density (more energy, total sugar, sodium and saturated fat-dense), such as warehouse-club, mass-merchandisers and convenience-stores are growing, representing a potential US public health concern. PMID:26437868

Organic Matter Remineralization Predominates Phosphorus Cycling in the Mid-Bay Sediments in the Chesapeake Bay

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

Sunendra, Joshi R.; Kukkadapu, Ravi K.; Burdige, David J.

2015-05-19

The Chesapeake Bay, the largest and most productive estuary in the US, suffers from varying degrees of water quality issues fueled by both point and non–point source nutrient sources. Restoration of the bay is complicated by the multitude of nutrient sources, their variable inputs and hydrological conditions, and complex interacting factors including climate forcing. These complexities not only restrict formulation of effective restoration plans but also open up debates on accountability issues with nutrient loading. A detailed understanding of sediment phosphorus (P) dynamics enables one to identify the exchange of dissolved constituents across the sediment- water interface and aid tomore » better constrain mechanisms and processes controlling the coupling between the sediments and the overlying waters. Here we used phosphate oxygen isotope ratios (δ18Op) in concert with sediment chemistry, XRD, and Mössbauer spectroscopy on the sediment retrieved from an organic rich, sulfidic site in the meso-haline portion of the mid-bay to identify sources and pathway of sedimentary P cycling and to infer potential feedback effect on bottom water hypoxia and surface water eutrophication. Isotope data indicate that the regeneration of inorganic P from organic matter degradation (remineralization) is the predominant, if not sole, pathway for authigenic P precipitation in the mid-bay sediments. We interpret that the excess inorganic P generated by remineralization should have overwhelmed any bottom-water and/or pore-water P derived from other sources or biogeochemical processes and exceeded saturation with respect to authigenic P precipitation. It is the first research that identifies the predominance of remineralization pathway against remobilization (coupled Fe-P cycling) pathway in the Chesapeake Bay. Therefore, these results are expected to have significant implications for the current understanding of P cycling and benthic-pelagic coupling in the bay, particularly on the source and pathway of P that sustains hypoxia and supports phytoplankton growth in the surface water.« less

Nutrient starvation leading to triglyceride accumulation activates the Entner Doudoroff pathway in Rhodococcus jostii RHA1.

PubMed

Juarez, Antonio; Villa, Juan A; Lanza, Val F; Lázaro, Beatriz; de la Cruz, Fernando; Alvarez, Héctor M; Moncalián, Gabriel

2017-02-27

Rhodococcus jostii RHA1 and other actinobacteria accumulate triglycerides (TAG) under nutrient starvation. This property has an important biotechnological potential in the production of sustainable oils. To gain insight into the metabolic pathways involved in TAG accumulation, we analysed the transcriptome of R jostii RHA1 under nutrient-limiting conditions. We correlate these physiological conditions with significant changes in cell physiology. The main consequence was a global switch from catabolic to anabolic pathways. Interestingly, the Entner-Doudoroff (ED) pathway was upregulated in detriment of the glycolysis or pentose phosphate pathways. ED induction was independent of the carbon source (either gluconate or glucose). Some of the diacylglycerol acyltransferase genes involved in the last step of the Kennedy pathway were also upregulated. A common feature of the promoter region of most upregulated genes was the presence of a consensus binding sequence for the cAMP-dependent CRP regulator. This is the first experimental observation of an ED shift under nutrient starvation conditions. Knowledge of this switch could help in the design of metabolomic approaches to optimize carbon derivation for single cell oil production.

Controls of event-based nutrient transport within nested headwater agricultural watersheds of the western Lake Erie basin

NASA Astrophysics Data System (ADS)

Williams, Mark R.; Livingston, Stanley J.; Penn, Chad J.; Smith, Douglas R.; King, Kevin W.; Huang, Chi-hua

2018-04-01

Understanding the processes controlling nutrient delivery in headwater agricultural watersheds is essential for predicting and mitigating eutrophication and harmful algal blooms in receiving surface waters. The objective of this study was to elucidate nutrient transport pathways and examine key components driving nutrient delivery processes during storm events in four nested agricultural watersheds (298-19,341 ha) in the western Lake Erie basin with poorly drained soils and an extensive artificial drainage network typical of the Midwestern U.S. Concentration-discharge hysteresis patterns of nitrate-nitrogen (NO3-N), dissolved reactive phosphorus (DRP), and particulate phosphorus (PP) occurring during 47 storm events over a 6 year period (2004-2009) were evaluated. An assessment of the factors producing nutrient hysteresis was completed following a factor analysis on a suite of measured environmental variables representing the fluvial and wider watershed conditions prior to, and during the monitored storm events. Results showed the artificial drainage network (i.e., surface tile inlets and subsurface tile drains) in these watersheds was the primary flow pathway for nutrient delivery to streams, but nutrient behavior and export during storm events was regulated by the flow paths to and the intensity of the drainage network, the availability of nutrients, and the relative contributions of upland and in-stream nutrient sources. Potential sources and flow pathways for transport varied among NO3-N, PP, and DRP with results underscoring the challenge of mitigating nutrient loss in these watersheds. Conservation practices addressing both nutrient management and hydrologic connectivity will likely be required to decrease nutrient loss in artificially drained landscapes.

The Importance of Animal Source Foods for Nutrient Sufficiency in the Developing World: The Zambia Scenario.

PubMed

Zhang, Zhiying; Goldsmith, Peter D; Winter-Nelson, Alex

2016-05-05

There have been successful interventions fortifying staple foods to mobilize micronutrients as well as agricultural efforts to raise yields of staple foods to increase food availability. Zambia serves as an interesting case study because since 1961 there has been a notable decline in the availability of animal source foods (ASFs) and pulses and a significant increase in the supply of cassava and vegetable oils. The shift in food availability was partly attributed to the agricultural success in high-yielding and drought-resistant varieties that made cassava and oil crops more affordable and readily available. In this research, we explore another policy strategy that involves ASF as a mechanism to help remedy micronutrient inadequacies in a population. A scenario modeling analysis compares the changes in the nutrient profile of the Zambian diet through adding either staple plant source foods (PSFs) or ASFs. The scenarios under study involve the addition of (1) 18 fl oz of whole cow's milk; (2) 60 g of beef, 30 g of chicken, and 5 g of beef liver; (3) milk plus meat; or (4) 83 g of maize flour, 123 g of cassava, and other staple PSF, that is, isocaloric to the "milk + meat" group. The findings alert program planners and policy makers to the value of increasing the availability, accessibility, and utilization of ASF to simultaneously address multiple nutrient deficiencies, as well as the nutrition challenges that remain when expanding the availability of plant-based staples. © The Author(s) 2016.

MODEL SIMULATION STUDIES OF SCALE-DEPENDENT GAIN IN STREAM NUTRIENT ASSIMILATIVE CAPACITY RESULTING FROM IMPROVING NUTRIENT RETENTION METRICS

EPA Science Inventory

Considering the difficulty in measuring restoration success for nonpoint source pollutants, nutrient assimilative capacity (NAS) offers an attractive systems-based metric. Here NAS was defined using an impulse-response model of nitrate fate and transport. Eleven parameters were e...

ESTUARINE-OCEAN EXCHANGE IN A NORTH PACIFIC ESTUARY: COMPARISON OF STEADY STATE AND DYNAMIC MODELS

EPA Science Inventory

Nutrient levels in coastal waters must be accurately assessed to determine the nutrient effects of increasing populations on coastal ecosystems. To accomplish this goal, in-field data with sufficient temporal resolution are required to define nutrient sources and sinks, and to ul...

Predicting Nitrogen in Streams : A Comparison of Two Estimates of Fertilizer Application

EPA Science Inventory

Decision makers frequently rely on water and air quality models to develop nutrient management strategies. Obviously, the results of these models (e.g., SWAT, SPARROW, CMAQ) are only as good as the nutrient source input data and recently the Nutrient Innovations Task Group has ca...

ESTIMATING NITROGEN AND TIDAL EXCHANGE IN A NORTH PACIFIC ESTUARY WITH EPA'S VISUAL PLUMES PDSW MODEL

EPA Science Inventory

Accurate assessments of nutrient levels in coastal waters are required to determine the nutrient effects of increasing population pressure on coastal ecosystems. To accomplish this goal, in-field data with sufficient temporal resolution are required to define nutrient sources an...

ESTIMATING NITROGEN AND TIDAL EXCHANGE IN A NORTH PACIFIC ESTUARY WITH EPA'S VISUAL PLUMES PDSW MODEL

EPA Science Inventory

Accurate assessments of nutrient levels in coastal waters are required to determine the nutrient effects of increasing population pressure on coastal ecosystems. To accomplish this goal, in-field data with sufficient temporal resolution are required to define nutrient sources and...

Assessing edge-of-field nutrient runoff from agricultural lands in the United States: How clean is clean enough?

USDA-ARS?s Scientific Manuscript database

Excess nutrients from numerous sources (e.g., agricultural and urban runoff, treatment plant discharge, streambank erosion) continue to adversely impact water resources in spite of improved treatment technologies and management practices. In fact, determination of cause(s) of accelerated nutrient e...

Nutrient Removal in Wastewater Treatment

ERIC Educational Resources Information Center

Shah, Kanti L.

1973-01-01

Discusses the sources and effects of nutrients in wastewater, and the methods of their removal in wastewater treatment. In order to conserve water resources and eliminate the cost of nutrient removal, treated effluent should be used wherever possible for irrigation, since it contains all the ingredients for proper plant growth. (JR)

Investigation of Colored Dissolved Organic Matter (CDOM) Optical Properties, Nutrients, and Salinity in Coastal Florida: Springshed to Estuaries

NASA Astrophysics Data System (ADS)

Arellano, Ana Rosa

Optical parameters measured via absorption spectroscopy and high-resolution fluorescence spectroscopy were used to characterize dissolved organic matter (DOM) in the springshed of Kings Bay, a spring-fed estuary located on Florida's Springs Coast. Over the past 40 years, springs supplying groundwater to Kings Bay have shown an increase in nitrate concentration. The overall goal of this project was to fingerprint wells and spring sites with elevated nitrogen concentrations using CDOM optical properties and establish relationships between nutrient and optical parameters. Samples were obtained from various sites: springs, Kings Bay surface (KBS), wells, coastal waters in and at the mouth of Crystal River (Coast) and lakes and rivers (LNR), during dry and wet seasons. The relationships between the environmental parameters and traditional optical parameters which provide insight into source characteristics were analyzed. Excitation emission matrix spectroscopy (EEMS) provided information about the concentration and chemical nature of organic matter in the study area. CDOM optical properties combined with salinity clearly separated the sources of fixed nitrogen in the Bay. Northern springs with elevated dissolved inorganic nitrogen (DIN) concentration had lower salinities and showed a presence of protein peaks. CDOM concentration was negatively correlated with total nitrogen (TN) and DIN, which suggests that these are subjected to anthropogenic influences. Humic peaks dominated the composition of the southern springs. CDOM concentrations were much higher than in the northern springs and there was a positive correlation between CDOM and both TN and DIN. These findings suggest that the fixed nitrogen in the southern springs is naturally occurring organic matter and the low concentrations may partially be a result of subsurface mixing of saltwater and freshwater in the aquifer. Thus, hypothesis testing showed that there was a significant difference between northern and southern springs Hypothesis testing also showed that there is a significant and unexpected positive relationship between CDOM and salinity studying Kings Bay, which is due to the low CDOM concentration in the springs discharging fresh water. This unique dataset also determined that the intercept of the mixing line was significantly different form zero. This indicates that CDOM is present and detectable at very low concentrations. Parallel Factor Analysis (PARAFAC) was used to evaluate CDOM composition from excitation emission matrix spectra (EEMs) and five components were identified: two humic, two marine humic, and one protein-like. The marine-like components, peak M, were produced in the marine environment and in meteoric groundwater. The study found a unique groundwater marker for coastal regions. Northern Kings Bay sites were characterized by a protein-like component, which has been associated with wastewater. Additional optical and environmental parameters were used in discriminate analysis, which successfully identified the CDOM markers for both natural and anthropogenic sources of nutrients in the environment. It is vital to improve the analysis of water, nutrients, and carbon from groundwater discharge into the coastal zone. Elevated DIN concentrations in groundwater are a widespread problem in Florida and over the past 30 years many spring waters have shown an increase in DIN concentrations. Nutrient discharge into delicate coastal areas can lead to ecological concerns. Investigating CDOM and nutrient distribution together can be a beneficial tool that can help differentiate sources from riverine/lacustrine, estuarine, marine, groundwater, and sewage impacted categories.

Transcriptomic response of the red tide dinoflagellate, Karenia brevis, to nitrogen and phosphorus depletion and addition.

PubMed

Morey, Jeanine S; Monroe, Emily A; Kinney, Amanda L; Beal, Marion; Johnson, Jillian G; Hitchcock, Gary L; Van Dolah, Frances M

2011-07-05

The role of coastal nutrient sources in the persistence of Karenia brevis red tides in coastal waters of Florida is a contentious issue that warrants investigation into the regulation of nutrient responses in this dinoflagellate. In other phytoplankton studied, nutrient status is reflected by the expression levels of N- and P-responsive gene transcripts. In dinoflagellates, however, many processes are regulated post-transcriptionally. All nuclear encoded gene transcripts studied to date possess a 5' trans-spliced leader (SL) sequence suggestive, based on the trypanosome model, of post-transcriptional regulation. The current study therefore sought to determine if the transcriptome of K. brevis is responsive to nitrogen and phosphorus and is informative of nutrient status. Microarray analysis of N-depleted K. brevis cultures revealed an increase in the expression of transcripts involved in N-assimilation (nitrate and ammonium transporters, glutamine synthetases) relative to nutrient replete cells. In contrast, a transcriptional signal of P-starvation was not apparent despite evidence of P-starvation based on their rapid growth response to P-addition. To study transcriptome responses to nutrient addition, the limiting nutrient was added to depleted cells and changes in global gene expression were assessed over the first 48 hours following nutrient addition. Both N- and P-addition resulted in significant changes in approximately 4% of genes on the microarray, using a significance cutoff of 1.7-fold and p ≤ 10-4. By far, the earliest responding genes were dominated in both nutrient treatments by pentatricopeptide repeat (PPR) proteins, which increased in expression up to 3-fold by 1 h following nutrient addition. PPR proteins are nuclear encoded proteins involved in chloroplast and mitochondria RNA processing. Correspondingly, other functions enriched in response to both nutrients were photosystem and ribosomal genes. Microarray analysis provided transcriptomic evidence for N- but not P-limitation in K. brevis. Transcriptomic responses to the addition of either N or P suggest a concerted program leading to the reactivation of chloroplast functions. Even the earliest responding PPR protein transcripts possess a 5' SL sequence that suggests post-transcriptional control. Given the current state of knowledge of dinoflagellate gene regulation, it is currently unclear how these rapid changes in such transcript levels are achieved.

Effects of rehydration nutrients on H2S metabolism and formation of volatile sulfur compounds by the wine yeast VL3.

PubMed

Winter, Gal; Henschke, Paul A; Higgins, Vincent J; Ugliano, Maurizio; Curtin, Chris D

2011-11-02

In winemaking, nutrient supplementation is a common practice for optimising fermentation and producing quality wine. Nutritionally suboptimal grape juices are often enriched with nutrients in order to manipulate the production of yeast aroma compounds. Nutrients are also added to active dry yeast (ADY) rehydration media to enhance subsequent fermentation performance. In this study we demonstrate that nutrient supplementation at rehydration also has a significant effect on the formation of volatile sulfur compounds during wine fermentations. The concentration of the 'fruity' aroma compounds, the polyfunctional thiols 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (3MHA), was increased while the concentration of the 'rotten egg' aroma compound, hydrogen sulfide (H2S), was decreased. Nutrient supplementation of the rehydration media also changed the kinetics of H2S production during fermentation by advancing onset of H2S production. Microarray analysis revealed that this was not due to expression changes within the sulfate assimilation pathway, which is known to be a major contributor to H2S production. To gain insight into possible mechanisms responsible for this effect, a component of the rehydration nutrient mix, the tri-peptide glutathione (GSH) was added at rehydration and studied for its subsequent effects on H2S formation. GSH was found to be taken up during rehydration and to act as a source for H2S during the following fermentation. These findings represent a potential approach for managing sulfur aroma production through the use of rehydration nutrients.

Development and Application of Regression Models for Estimating Nutrient Concentrations in Streams of the Conterminous United States, 1992-2001

USGS Publications Warehouse

Spahr, Norman E.; Mueller, David K.; Wolock, David M.; Hitt, Kerie J.; Gronberg, JoAnn M.

2010-01-01

Data collected for the U.S. Geological Survey National Water-Quality Assessment program from 1992-2001 were used to investigate the relations between nutrient concentrations and nutrient sources, hydrology, and basin characteristics. Regression models were developed to estimate annual flow-weighted concentrations of total nitrogen and total phosphorus using explanatory variables derived from currently available national ancillary data. Different total-nitrogen regression models were used for agricultural (25 percent or more of basin area classified as agricultural land use) and nonagricultural basins. Atmospheric, fertilizer, and manure inputs of nitrogen, percent sand in soil, subsurface drainage, overland flow, mean annual precipitation, and percent undeveloped area were significant variables in the agricultural basin total nitrogen model. Significant explanatory variables in the nonagricultural total nitrogen model were total nonpoint-source nitrogen input (sum of nitrogen from manure, fertilizer, and atmospheric deposition), population density, mean annual runoff, and percent base flow. The concentrations of nutrients derived from regression (CONDOR) models were applied to drainage basins associated with the U.S. Environmental Protection Agency (USEPA) River Reach File (RF1) to predict flow-weighted mean annual total nitrogen concentrations for the conterminous United States. The majority of stream miles in the Nation have predicted concentrations less than 5 milligrams per liter. Concentrations greater than 5 milligrams per liter were predicted for a broad area extending from Ohio to eastern Nebraska, areas spatially associated with greater application of fertilizer and manure. Probabilities that mean annual total-nitrogen concentrations exceed the USEPA regional nutrient criteria were determined by incorporating model prediction uncertainty. In all nutrient regions where criteria have been established, there is at least a 50 percent probability of exceeding the criteria in more than half of the stream miles. Dividing calibration sites into agricultural and nonagricultural groups did not improve the explanatory capability for total phosphorus models. The group of explanatory variables that yielded the lowest model error for mean annual total phosphorus concentrations includes phosphorus input from manure, population density, amounts of range land and forest land, percent sand in soil, and percent base flow. However, the large unexplained variability and associated model error precluded the use of the total phosphorus model for nationwide extrapolations.

Predicting nutrient responses to mitigation at catchment to national scale: the UK research platform (Invited)

NASA Astrophysics Data System (ADS)

Johnes, P.

2013-12-01

Nutrient enrichment of waters from land-based and atmospheric sources presents a significant management challenge, requiring effective stakeholder engagement and policy development, properly underpinned by robust scientific evidence. The challenge is complex, raising significant questions about the specific sources, apportionment and pathways that determine nutrient enrichment and the key priorities for effective management and policy intervention. This paper presents outputs from 4 major UK research programmes: the Defra Demonstration Test Catchments programme (DTC), the Environment Agency's Catchment Sensitive Farming monitoring and evaluation programme (CSF), Natural Resources Wales Welsh Catchment Initiative (WCI) and the NERC Environmental Virtual Observatory programme (EVOp). Funded to meet this challenge, they are delivering new understanding of the rates and sources of pollutant fluxes from land to water, their impacts on ecosystem goods and services, and likely trends under future climate and land use change from field to national scale. DTC, a 12m investment by the UK Government, has set up long-term, high resolution research platforms equipped with novel telemetered sensor networks to monitor stream ecosystem responses to on-farm mitigation measures at a representative scale for catchment management. Ecosystem structural and functional responses and bulk hydrochemistry are also being monitored using standard protocols. CSF has set up long-term, enhanced monitoring in 8 priority catchments, with monthly monitoring in a further 72 English catchments and 6 Welsh priority catchments, to identify shifts in pollutant flux to waters resulting from mitigation measures in priority areas and farming sectors. CSF and WCI have contributed to >50 million of targeted farm improvements to date, representing a significant shift in farming practice. Each programme has generated detailed evidence on stream ecosystem responses to targeted mitigation. However, to provide effective underpinning for policy the major challenge has been to upscale this knowledge beyond these data-rich systems and identify the dominant contributing areas and priorities for management intervention to control nutrient flux and ecological impacts in data-poor systems which are located downstream from existing monitoring infrastructure or are in unmonitored catchments in remote locations. EVOp has directly addressed this challenge, developing a cloud computing enabled National Biogeochemical Modelling Framework to support ensemble modelling, knowledge capture and transfer from DTC, CSF, WCI and data-rich research catchments. This platform provides opportunities for further development of national biogeochemical modelling capability, allowing upscaled predictions from plot to catchment and national scale, enabling knowledge transfer from data-rich to data-poor areas. This paper presents initial findings from these research platforms, identifying the key priorities for action emerging from our national scale scenario analysis, and future research directions to further improve understanding, prediction and management capability in nutrient enriched waters and their catchments under changing climate and land use.

Reliability and Validity of Food Frequency Questionnaire and Nutrient Biomarkers in Elders With and Without Mild Cognitive Impairment

PubMed Central

Bowman, Gene L.; Shannon, Jackilen; Ho, Emily; Traber, Maret G.; Frei, Balz; Oken, Barry S.; Kaye, Jeffery A.; Quinn, Joseph F.

2010-01-01

Introduction There is great interest in nutritional strategies for the prevention of age-related cognitive decline, yet the best methods for nutritional assessment in populations at risk for dementia are still evolving. Our study objective was to test the reliability and validity of two common nutritional assessments (plasma nutrient biomarkers and Food Frequency Questionnaire) in people at risk for dementia. Methods Thirty-eight elders, half with amnestic -Mild Cognitive Impairment and half with intact cognition were recruited. Nutritional assessments were collected together at baseline and again at 1 month. Intraclass and Pearson correlation coefficients quantified reliability and validity. Results Twenty-six nutrients were examined and reliability was very good or better for 77% (20/26, ICC ≥ .75) of the plasma nutrient biomarkers and for 88% of the FFQ estimates. Twelve of the plasma nutrient estimates were as reliable as the commonly measured plasma cholesterol (ICC=.92). FFQ and plasma long-chain fatty acids (docosahexaenoic acid, r =.39, eicosapentaenoic acid, r = .39) and carotenoids (α-carotene, r =.49; lutein + zeaxanthin, r = .48; β-carotene, r = .43; β-cryptoxanthin, r = .41) were correlated, but no other FFQ estimates correlated with respective nutrient biomarkers. Correlations between FFQ and plasma fatty acids and carotenoids were significantly stronger after removing subjects with MCI. Conclusion The reliability and validity of plasma and FFQ nutrient estimates vary according to the nutrient of interest. Memory deficit attenuates FFQ estimate validity and inflates FFQ estimate reliability. Many plasma nutrient biomarkers have very good reliability over 1-month regardless of memory state. This method can circumvent sources of error seen in other less direct methods of nutritional assessment. PMID:20856100

Effect of ground corn cobs as a fiber source in total mixed ration on feed intake, milk yield and milk composition in tropical lactating crossbred Holstein cows.

PubMed

Wachirapakorn, Chalong; Pilachai, Krung; Wanapat, Metha; Pakdee, Pawadee; Cherdthong, Anusorn

2016-12-01

The aim of this study was to evaluate the effect of ground corn cobs (GCC) as a sole fiber source in total mixed ration (TMR) on feed intake, milk yield and milk composition in tropical lactating crossbred Holstein cows. Four multiparous crossbreds Holstein Friesian dairy cows with an initial body weight (BW) of 415.5 ± 26.20 kg were used in a 4 × 4 Latin square design. The dietary treatments of TMR contained a roughage-to-concentrate ratio of 40:60. The roughage source was used at different ratios of GCC to rice straw (RS) at 100:0, 82.5:17.5, 67.5:32.5, and 50:50 for TMR1 to TMR4, respectively. The results revealed significant improvements in intake of dry matter, protein, neutral detergent fiber (NDF) and metabolizable energy (ME) for TMR1 and TMR2 ( P  < 0.05), while the digestibility of nutrients was not altered by the treatments ( P  ≥ 0.05). Ground corn cobs was used for up to 100% of the total roughage without affecting milk production. Moreover, ruminal pH, temperature, ammonia-nitrogen (NH 3 -N) and volatile fatty acid (VFA) concentrations were not impacted by the treatments ( P  > 0.05). However, milk yield was significantly different among the GCC:RS ratios ( P  < 0.05) and was the highest in TMR1 and TMR2 (13.1 kg/d), while the milk compositions were not changed ( P  > 0.05). The results imply that using GCC as a whole roughage source significantly improved nutrients intake and milk yield in dairy cows raised in tropical areas.

Temporal variability in domestic point source discharges and their associated impact on receiving waters.

PubMed

Richards, Samia; Withers, Paul J A; Paterson, Eric; McRoberts, Colin W; Stutter, Marc

2016-11-15

Discharges from the widely distributed small point sources of pollutants such as septic tanks contribute to microbial and nutrient loading of streams and can pose risks to human health and stream ecology, especially during periods of ecological sensitivity. Here we present the first comprehensive data on the compositional variability of septic tank effluents (STE) as a potential source of water pollution during different seasons and the associated links to their influence on stream waters. To determine STE parameters and nutrient variations, the biological and physicochemical properties of effluents sampled quarterly from 12 septic tank systems were investigated with concurrent analyses of upstream and downstream receiving waters. The study revealed that during the warmer dryer months of spring and summer, effluents were similar in composition, as were the colder wetter months of autumn and winter. However, spring/summer effluents differed significantly (P<0.05) from autumn/winter for concentrations of biological oxygen demand (BOD), arsenic, barium (Ba), cobalt, chromium, manganese, strontium (Sr), titanium, tungsten (W) and zinc (Zn). With the exception of BOD, Ba and Sr which were greater in summer and spring, the concentrations of these parameters were greater in winter. Receiving stream waters also showed significant seasonal variation (P≤0.05) in alkalinity, BOD, dissolved organic carbon, sulphate, sulphur, lithium, W, Zn and Escherichiacoli abundance. There was a clear significant influence of STE on downstream waters relative to upstream from the source (P<0.05) for total suspended solids, total particulate P and N, ammonium-N, coliforms and E. coli. The findings of this study found seasonal variation in STE and place effluent discharges as a factor affecting adjacent stream quality and call for appropriate measures to reduce or redirect STE discharges away from water courses. Copyright © 2016 Elsevier B.V. All rights reserved.

Sources and transport of algae and nutrients in a Californian river in a semi-arid climate

USGS Publications Warehouse

Ohte, N.; Dahlgren, R.A.; Silva, S.R.; Kendall, C.; Kratzer, C.R.; Doctor, D.H.

2007-01-01

1. To elucidate factors contributing to dissolved oxygen (DO) depletion in the Stockton Deep Water Ship Channel in the lower San Joaquin River, spatial and temporal changes in algae and nutrient concentrations were investigated in relation to flow regime under the semiarid climate conditions. 2. Chlorophyll-a (chl-a) concentration and loads indicated that most algal biomass was generated by in-stream growth in the main stem of the river. The addition of algae from tributaries and drains was small (c.15% of total chl-a load), even though high concentrations of chl-a were measured in some source waters. 3. Nitrate and soluble-reactive phosphorus (SRP) were available in excess as a nutrient source for algae. Although nitrate and SRP from upstream tributaries contributed (16.9% of total nitrate load and 10.8% of total SRP load), nutrients derived from agriculture and other sources in the middle and lower river reaches were mostly responsible (20.2% for nitrate and 48.0% for SRP) for maintaining high nitrate and SRP concentrations in the main stem. 4. A reduction in nutrient discharge would attenuate the algal blooms that accelerate DO depletion in the Stockton Deep Water Ship Channel. The N : P ratio, in the main stem suggests that SRP reduction would be a more viable option for algae reduction than nitrogen reduction. 5. Very high algal growth rates in the main stem suggest that reducing the algal seed source in upstream areas would also be an effective strategy. ?? 2007 Blackwell Publishing Ltd.

Modelling of point and diffuse pollution: application of the Moneris model in the Ipojuca river basin, Pernambuco State, Brazil.

PubMed

de Lima Barros, Alessandra Maciel; do Carmo Sobral, Maria; Gunkel, Günter

2013-01-01

Emissions of pollutants and nutrients are causing several problems in aquatic ecosystems, and in general an excess of nutrients, specifically nitrogen and phosphorus, is responsible for the eutrophication process in water bodies. In most developed countries, more attention is given to diffuse pollution because problems with point pollution have already been solved. In many non-developed countries basic data for point and diffuse pollution are not available. The focus of the presented studies is to quantify nutrient emissions from point and diffuse sources in the Ipojuca river basin, Pernambuco State, Brazil, using the Moneris model (Modelling Nutrient Emissions in River Systems). This model has been developed in Germany and has already been implemented in more than 600 river basins. The model is mainly based on river flow, water quality and geographical information system data. According to the Moneris model results, untreated domestic sewage is the major source of nutrients in the Ipojuca river basin. The Moneris model has shown itself to be a useful tool that allows the identification and quantification of point and diffuse nutrient sources, thus enabling the adoption of measures to reduce them. The Moneris model, conducted for the first time in a tropical river basin with intermittent flow, can be used as a reference for implementation in other watersheds.

Nutrient inputs into the Gulf of Finland: Trends and water protection targets

NASA Astrophysics Data System (ADS)

Knuuttila, Seppo; Räike, Antti; Ekholm, Petri; Kondratyev, Sergey

2017-07-01

The catchment area of the Gulf of Finland (GOF) is nearly 14 times larger than the sea area and is home to 12 million people. The GOF is thus heavily polluted by nutrients, and eutrophication is one of the major environmental concerns. The aim of this study was to estimate trends in the nutrient input and to evaluate whether current water protection targets (national, EU, HELCOM) will be achieved. We used both national and international (HELCOM) databases to evaluate nutrient inputs from the surrounding three countries (Estonia, Finland and Russia). The average nitrogen (N) input into the GOF was 112,000 t y- 1 for the period 2009-2013, with rivers responsible for 79%, direct point sources accounting for 10% and deposition for 11% of the input. Phosphorus (P) input was 4270 t y- 1, of which rivers were responsible for 88% and point sources for 12%. The largest proportions (61% for N and 73% for P) of the inputs came from Russia, despite the specific areal inputs (input divided by land area) being smaller than in Estonia and Finland. The changes in nutrient inputs into the GOF are largely due to the changes in Russian inputs, and in particular changes in the nutrient fluxes of the River Neva. The latest available flow-normalised data showed that N export decreased slightly from 1994 to 2010, while flow-normalised P export had clearly decreased by 2010. The P input ending up in the GOF as a whole has decreased significantly over the past 10 years as a result of the re-construction of wastewater treatment infrastructure in St Petersburg and following control of a P leak at the Phosphorit factory in 2012. This measure also explains the steep decrease in riverine P export during recent years. Further reduction of inputs to meet the ambitious nutrient reduction goals of HELCOM and of WFD seems to be a challenge for Finland and Estonia in particular. Russia appears to have already reached approximately 90% of the BSAP's reduction target, with fulfilment of the remainder of the P target appearing a fairly realistic aim as well.

Using Nd and Sr isotopes to trace dust and volcanic inputs to soils on French Guadeloupe Island

NASA Astrophysics Data System (ADS)

Guo, J.; Pereyra, Y.; Ma, L.; Gaillardet, J.; Sak, P. B.; Bouchez, J.

2017-12-01

Soil is at the central part of the Critical Zone for its important roles in sustaining ecosystems and agriculture. At French Guadeloupe, a tropical humid volcanic island, previous studies have shown that the mineral nutrient elements such as K, Na, Ca, and Mg are highly depleted in the surface soil. And mineral nutrients introduced by dusts are an important mineral nutrient source for vegetation growth in this area. It is important to understand and quantify the sources of the mineral dust added to surface soils. Nd isotope ratios, due to their distinct signatures between two unique end-members in soils for this area: the young volcanic areas like Guadeloupe and the dust source region from the old continental shields like Sahara Desert, can be a robust tracer to understand this critical process. Nevertheless, Sr isotope ratios can trace the inputs of marine aerosols. Here we present a new Nd isotope study on Guadeloupe soil depth profiles, combined with previous Sr isotope data, to fingerprint the sources of dust and volcanic inputs into soils. Soil samples from three surface profiles (0 - 1000cm deep) at different locations of the Guadeloupe Island were systematically analyzed. The results show distinct depth variations for Nd isotope signature along profiles. For all profiles, deep soils are relatively consisted with bedrock value (ɛNd: 5.05). But in surface soils (0-600cm), unlike Sr isotope ratios that are significantly modified by marine aerosol input, Nd isotope ratios show similar decrease (to ɛNd:-10) and frequent fluctuations toward the surface, suggesting dust is the dominant source of Nd in these soils. This conclusion is further supported by REE and other trace element data. Thus, with a simplified two end-member model, Sahara dust contributes the Nd percentages in soils varying from 10.7% at the deepest profiles to 69.5% on surface, showing a significant amount of Nd on the surface soil came from dust source. The deep soil profiles are also characterized by the presence of Nd isotope spikes with negative values, suggesting dust signatures at depth. Such a feature could be related to the presence of a paleo-soil surface at the spike depth that was buried by later volcanic eruption. Both Nd and Sr isotopes hence show dust and volcanic inputs are important factors for soil developments on French Guadeloupe Island.

Design, implementation, and initial results from a water-quality monitoring network for Atlanta, Georgia, USA

USGS Publications Warehouse

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

2005-01-01

In cooperation with the City of Atlanta, Georgia, the US Geological Survey has designed and implemented a water-quantity and quality monitoring network that measures a variety of biological and chemical constituents in water and suspended sediment. The network consists of 20 long-term monitoring sites and is intended to assess water-quality trends in response to planned infrastructural improvements. Initial results from the network indicate that nonpoint-source contributions may be more significant than point-source contributions for selected sediment associated trace elements and nutrients. There also are indications of short-term discontinuous point-source contributions of these same constituents during baseflow.

Meeting Expanding Needs to Collect Food Intake Specificity: The Nutrition Data System for Research (NDS-R)

NASA Technical Reports Server (NTRS)

VanHeel, Nancy; Pettit, Janet; Rice, Barbara; Smith, Scott M.

2003-01-01

Food and nutrient databases are populated with data obtained from a variety of sources including USDA Reference Tables, scientific journals, food manufacturers and foreign food tables. The food and nutrient database maintained by the Nutrition Coordinating Center (NCC) at the University of Minnesota is continually updated with current nutrient data and continues to be expanded with additional nutrient fields to meet diverse research endeavors. Data are strictly evaluated for reliability and relevance before incorporation into the database; however, the values are obtained from various sources and food samples rather than from direct chemical analysis of specific foods. Precise nutrient values for specific foods are essential to the nutrition program at the National Aeronautics and Space Administration (NASA). Specific foods to be included in the menus of astronauts are chemically analyzed at the Johnson Space Center for selected nutrients. A request from NASA for a method to enter the chemically analyzed nutrient values for these space flight food items into the Nutrition Data System for Research (NDS-R) software resulted in modification of the database and interview system for use by NASA, with further modification to extend the method for related uses by more typical research studies.

Developement of watershed and reference loads for a TMDL in Charleston Harbor System, SC.

Treesearch

Silong Lu; Devenra Amatya; Jamie Miller

2005-01-01

It is essential to determine point and non-point source loads and their distribution for development of a dissolved oxygen (DO) Total Maximum Daily Load (TMDL). A series of models were developed to assess sources of oxygen-demand loadings in Charleston Harbor, South Carolina. These oxygen-demand loadings included nutrients and BOD. Stream flow and nutrient...

Natural selection for costly nutrient recycling in simulated microbial metacommunities.

PubMed

Boyle, Richard A; Williams, Hywel T P; Lenton, Timothy M

2012-11-07

Recycling of essential nutrients occurs at scales from microbial communities to global biogeochemical cycles, often in association with ecological interactions in which two or more species utilise each others' metabolic by-products. However, recycling loops may be unstable; sequences of reactions leading to net recycling may be parasitised by side-reactions causing nutrient loss, while some reactions in any closed recycling loop are likely to be costly to participants. Here we examine the stability of nutrient recycling loops in an individual-based ecosystem model based on microbial functional types that differ in their metabolism. A supplied nutrient is utilised by a "source" functional type, generating a secondary nutrient that is subsequently used by two other types-a "mutualist" that regenerates the initial nutrient at a growth rate cost, and a "parasite" that produces a refractory waste product but does not incur any additional cost. The three functional types are distributed across a metacommunity in which separate patches are linked by a stochastic diffusive migration process. Regions of high mutualist abundance feature high levels of nutrient recycling and increased local population density leading to greater export of individuals, allowing the source-mutualist recycling loop to spread across the system. Individual-level selection favouring parasites is balanced by patch-level selection for high productivity, indirectly favouring mutualists due to the synergistic productivity benefits of the recycling loop they support. This suggests that multi-level selection may promote nutrient cycling and thereby help to explain the apparent ubiquity and stability of nutrient recycling in nature.

Forecasting future phosphorus export to the Laurentian Great Lakes from land-derived nutrient inputs

NASA Astrophysics Data System (ADS)

LaBeau, M. B.; Robertson, D. M.; Mayer, A. S.; Pijanowski, B. C.

2011-12-01

Anthropogenic use of the land through agricultural and urban activities has significantly increased phosphorus loading to rivers that flow to the Great Lakes. Phosphorus (P) is a critical element in the eutrophication of the freshwater ecosystems, most notably the Great Lakes. To better understand factors influencing phosphorus delivery to aquatic systems and thus their potential harmful effects to lake ecosystems, models that predict P export should incorporate account for changing changes in anthropogenic activities. Land-derived P from high yielding sources, such as agriculture and urban areas, affect eutrophication at various scales (e.g. specific bays to all of Lake Erie). SPARROW (SPAtially Referenced Regression On Watershed attributes) is a spatially explicit watershed model that has been used to understand linkages between land-derived sources and nutrient transport to the Great Lakes. The Great Lakes region is expected to experience a doubling of urbanized areas along with a ten percent increase in agricultural use over the next 40 years, which is likely to increase P loading. To determine how these changes will impact P loading, SPARROW have been developed that relate changes in land use to changes in nutrient sources, including relationships between row crop acreage and fertilizer intensity and urban land use and point source intensity. We used land use projections from the Land Transformation Model, a, spatially explicit, neural-net based land change model. Land use patterns from current to 2040 were used as input into HydroSPARROW, a forecasting tool that enables SPARROW to simulate the effects of various land-use and climate scenarios. Consequently, this work is focusing on understanding the effects of how specific agriculture and urbanization activities affect P loading in the watersheds of the Laurentian Great Lakes to potentially find strategies to reduce the extent and severity of future eutrophication.

Assimilation of organic and inorganic nutrients by Erica root fungi from the fynbos ecosystem.

PubMed

Bizabani, Christine; Dames, Joanna Felicity

2016-03-01

Erica dominate the fynbos ecosystem, which is characterized by acidic soils that are rich in organic matter. The ericaceae associate with ericoid mycorrhizal (ERM) fungi for survival. In this study fungal biomass accumulation in vitro was used to determine nutrient utilisation of various inorganic and organic substrates. This is an initial step towards establishment of the ecological roles of typical ERM fungi and other root fungi associated with Erica plants, with regard to host nutrition. Meliniomyces sp., Acremonium implicatum, Leohumicola sp., Cryptosporiopsis erica, Oidiodendron maius and an unidentified Helotiales fungus were selected from fungi previously isolated and identified from Erica roots. Sole nitrogen sources ammonium, nitrate, arginine and Bovine Serum Albumin (BSA) were tested. Meliniomyces and Leohumicola species were able to utilise BSA effectively. Phosphorus nutrition was tested using orthophosphate, sodium inositol hexaphosphate and DNA. Most isolates preferred orthophosphate. Meliniomyces sp. and A. implicatum were able to accumulate significant biomass using DNA. Carbon utilisation was tested using glucose, cellobiose, carboxymethylcellulose, pectin and tannic acid substrates. All fungal isolates produced high biomass on glucose and cellobiose. The ability to utilize organic nutrient sources in culture, illustrates their potential role of these fungi in host nutrition in the fynbos ecosystem. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Instream Attenuation of Nitrogen and Phosphorus in Non-Point Source Dominated Streams: Hydrologic and Biogeochemical Controls

NASA Astrophysics Data System (ADS)

Bray, E. N.; Chen, X.; Keller, A. A.

2010-12-01

Non-point source inputs of total nitrogen (TN) and total phosphorus (TP) in rivers are the leading causes of water quality degradation in the United States (Turner and Rabalais, 2003; Broussard and Turner, 2009). Yet it remains a challenge to adequately quantify the relative role and influence of physical hydrological processes versus biogeochemical processes on the attenuation of TN and TP for individual river reaches. A watershed-scale study of instream dynamics and attenuation of TN and TP in northeastern U.S. headwater streams demonstrates that physical and hydrological processes exert greater control over nutrient removal than biogeochemical processes. To explore these interactions under various attenuation scenarios, we developed the watershed-scale model (WARMF) for 97 catchments to simulate watershed processes, hydrology, and diffuse source loads of nutrients. We simulated a hypothetical nutrient release at a rate of 1 kg/d of TN (50% as ammonium and 50% as nitrate) and TP (100% as phosphate) to predict response lengths of downstream catchments. Resulting attenuation factors are presented as the change in mean load at a given location, normalized to the change in the catchment in which the load is applied. Results indicate that for most catchments, the TN and TP load increase is attenuated from the stream within a few tens of kilometers. Fifty percent attenuation occurs across length scales ranging from a few hundreds of meters to kilometers if the load is introduced in the headwaters, indicating the most rapid nutrient removal occurs in the smallest headwater streams but generally decreases with distance downstream. There are some differences in the attenuation factors for TN and TP, although the pattern of attenuation is the same. Sensitivity analyses highlight five hydrological parameters of paramount importance to concentrations of N and P, namely precipitation, evaporation coefficients (magnitude and skewness), soil layer thickness, soil saturated moisture and soil hydraulic conductivity. These model parameters have a significant effect on the concentrations of nutrients, with TN exhibiting greater sensitivity. Further, attenuation results suggest that stream depth, flow regime, and density of agriculture in small headwater streams are potentially important controls to nutrient uptake and removal; i.e. during periods of low flow, dilution is reduced, attenuation length increases, and removal processes may be dominated by settling as opposed to biogeochemistry. Instream attenuation and model results can be used to assess 1) the scale and nature of best management practices which must be adopted to result in nutrient reductions, 2) the downstream distance at which load reductions will be effective, and 3) the hydrological characteristics of the river network which exert considerable influence on attenuation lengths and nutrient removal.

Effect of enhanced homestead food production and aquaculture on dietary intakes of women and children in rural Cambodia: A cluster randomized controlled trial.

PubMed

Verbowski, Vashti; Talukder, Zaman; Hou, Kroeun; Sok Hoing, Ly; Michaux, Kristina; Anderson, Victoria; Gibson, Rosalind; Li, Kathy H; Lynd, Larry D; McLean, Judy; Green, Tim J; Barr, Susan I

2018-01-05

The Cambodian diet is low in nutrient-dense animal-source foods. Enhanced homestead food production (EHFP) and aquaculture, which increase availability of nutrient-dense foods, are promising interventions to improve dietary intake. This study examined the effect of EHFP with or without aquaculture on dietary intake and prevalence of inadequate intake of select nutrients among women and children living in rural Cambodia, compared to controls. In a registered, cluster randomized controlled trial in Prey Veng, Cambodia, 10 households in each of 90 villages (n = 900) were randomized by village to receive EHFP, EHFP plus aquaculture, or control. After 22-month intervention, 24-hr dietary recalls (24HRs) were collected from mothers aged 18-50 years (n = 429) and their children aged 6 months-7 years (n = 421), reported by their mothers. Usual intake distributions (generated using 24HRs and repeat 24HRs on a subsample) were used to estimate prevalence of inadequate intake. Compared to controls, women in the EHFP group had significantly higher zinc (+1.0 mg/d) and Vitamin A (+139 retinol activity equivalents/d) intakes, and women in the EHFP plus aquaculture group had significantly higher iron (+2.7 mg/d), Vitamin A (+191 retinol activity equivalents/d), and riboflavin (+0.17 mg/d) intakes. Women in the EHFP plus aquaculture group also had significantly lower prevalence of inadequate iron (-7%, at 10% bioavailability), Vitamin A (-19%), and riboflavin (-17%) intakes, compared to controls. No significant differences in intakes or nutrient adequacy were observed among children or between EHFP and EHFP plus aquaculture groups. The biological importance of the small differences in nutrient intakes among women remains to be established. © 2018 John Wiley & Sons Ltd.

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

Impact of irrigation scheduling on pore water nitrate and phosphate in coastal plains soils with corn production

USDA-ARS?s Scientific Manuscript database

Agriculture is one of the most important sources of nutrient contamination, mainly inorganic nitrogen (N) fertilization of intensive crops, such as corn (Zea mays L). Proper irrigation and nutrient management can reduce nutrient leaching while maintaining crop yield, which is critical in enhancing t...

Crop nutrient recovery from applied fish coproducts

USDA-ARS?s Scientific Manuscript database

The Alaska fishing industry produces over 1,000,000 metric tons of fish byproducts annually, and most of them are not used. Most food in Alaska is imported. Fish byproducts are rich in plant essential nutrients and can be used as nutrient sources for crop production. The objective of the study was t...

Nutrient cycling in an agroforestry alley cropping system receiving poultry litter or nitrogen fertilizer

USDA-ARS?s Scientific Manuscript database

Optimal utilization of animal manures as a plant nutrient source should also prevent adverse impacts on water quality. The objective of this study was to evaluate long-term poultry litter and N fertilizer application on nutrient cycling following establishment of an alley cropping system with easter...

LONG-TERM CHANGES IN WATERSHED NUTRIENT INPUTS AND RIVERINE EXPORTS IN THE NEUSE RIVER, NORTH CAROLINA. (U915590)

EPA Science Inventory

We compared patterns of historical watershed nutrient inputs with in-river nutrient loads for the Neuse River, NC. Basin-wide sources of both nitrogen and phosphorus have increased substantially during the past century, marked by a sharp increase in the last 10 years resulting...

Sources of nutrients to nearshore areas of a eutrophic estuary: Implications for nutrient-enhanced acidification in Puget Sound

EPA Science Inventory

Ocean acidification has recently been highlighted as a major stressor for coastal organisms. Further work is needed to assess the role of anthropogenic nutrient additions in eutrophied systems on local biological processes, and how this interacts with CO2emission-driven acidific...

DEVELOPING NUTRIENT CRIETERIA FOR ESTUARIES WITH VARIABLE OCEAN INPUTS: AN EXAMPLE FROM THE PACIFIC NORTHWEST

EPA Science Inventory

Estuaries in the Pacific Northwest have major intraannual and within estuary variation in sources and magnitudes of nutrient inputs. To develop an approach for setting nutrient criteria for these systems, we conducted a case study for Yaquina Bay, OR based on a synthesis of resea...

Nutrient Loss in Runoff from Turf: Effect on Surface Water Quality

USDA-ARS?s Scientific Manuscript database

Excess nutrients in surface waters may result in enhanced algal blooms and plant growth that can lead to eutrophication and a decline in water quality. The applicatin of fertilizer to golf courses may be a source of nutrients to surface waters. Runoff studies were conducted to measure applied nitrog...

Iron deficiency-induced changes in growth reveal differences in nutrient partitioning between two ecotypes of Medicago truncatula

USDA-ARS?s Scientific Manuscript database

Enhancing the nutritional quality of crops is of international importance, and multiple methods have been utilized to increase the nutrient content of legume seeds. Because nutrients mobilized from source leaves to growing reproductive sink tissues greatly contribute to the final composition of the ...

Improved Hypoxia Modeling for Nutrient Control Decisions in the Gulf of Mexico

NASA Technical Reports Server (NTRS)

Habib, Shaid; Pickering, Ken; Tzortziou, Maria; Maninio, Antonio; Policelli, Fritz

2010-01-01

As required by the Harmful Algal Bloom and Hypoxia Research Control Act of 1998, the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force issued the 2001 Gulf Hypoxia Action Plan (updated in 2008). In response to the Gulf Hypoxia Action Plan of 2001 (updated in 2008), the EPA Gulf of Mexico Hypoxia Modeling and Monitoring Project has established a detailed model for the Mississippi-Attchafalaya River Basin which provides a capability to forecast the multi-source nutrient loading to the Gulf and the subsequent bio-geochemical processes leading to hypoxic conditions and subsequent effects on Gulf habitats and fisheries. The primary purpose of the EPA model is to characterize the impacts of nutrient management actions, or proposed actions on the spatial and temporal characteristics of the Gulf hypoxic zone. The model is expected to play a significant role in determining best practices and improved strategies for incentivizing nutrient reduction strategies, including installation of on-farm structures to reduce sediment and nutrient runoff, use of cover crops and other agricultural practices, restoration of wetlands and riparian buffers, improved waste water treatment and decreased industrial nitrogen emissions. These decisions are currently made in a fragmented way by federal, state, and local agencies, using a variety of small scale models and limited data. During the past three years, EPA has collected an enormous amount of in-situ data to be used in the model. We believe that the use of NASA satellite data products in the model and for long term validation of the model has the potential to significantly increase the accuracy and therefore the utility of the model for the decision making described above. This proposal addresses the Gulf of Mexico Alliance (GOMA) priority issue of reductions in nutrient inputs to coastal ecosystem. It further directly relates to water quality for healthy beaches and shellfish beds and wetland and coastal conservation restoration.

Influence of Acacia trees on soil nutrient levels in arid lands

NASA Astrophysics Data System (ADS)

De Boever, Maarten; Gabriels, Donald; Ouessar, Mohamed; Cornelis, Wim

2014-05-01

The potential of scattered trees as keystone structures in restoring degraded environments is gaining importance. Scattered trees have strong influence on their abiotic environment, mainly causing changes in microclimate, water budget and soil properties. They often function as 'nursing trees', facilitating the recruitment of other plants. Acacia raddiana is such a keystone species which persists on the edge of the Sahara desert. The study was conducted in a forest-steppe ecosystem in central Tunisia where several reforestation campaigns with Acacia took place. To indentify the impact of those trees on soil nutrients, changes in nutrient levels under scattered trees of three age stages were examined for the upper soil layer (0-10 cm) at five microsites with increasing distance from the trunk. In addition, changes in soil nutrient levels with depth underneath and outside the canopy were determined for the 0-30 cm soil layer. Higher concentrations of organic matter (OM) were found along the gradient from underneath to outside the canopy for large trees compared to medium and small trees, especially at microsites close to the trunk. Levels of soluble K, electrical conductivity (EC), available P, OM, total C and N decreased whereas pH and levels of soluble Mg increased with increasing distance from tree. Levels of soluble Ca and Na remained unchanged along the gradient. At the microsite closest to the trunk a significant decrease in levels of soluble K, EC, OM, available P, total C and N, while a significant increase in pH was found with increasing depth. The concentration of other nutrients remained unchanged or declined not differently underneath compared to outside the canopy with increasing depth. Differences in nutrient levels were largely driven by greater inputs of organic matter under trees. Hence, Acacia trees can affect the productivity and reproduction of understory species with the latter in term an important source of organic matter. This positive feedback mechanism is of crucial importance for soil nutrient conservation and the restoration of degraded arid environments.

[Pollution distribution and potential ecological risk assessment of heavy metals in sediments from the different eastern dredging regions of Lake Taihu].

PubMed

Mao, Zhi-Gang; Gu, Xiao-Hong; Lu, Xiao-Ming; Zeng, Qing-Fei; Gu, Xian-Kun; Li, Xu-Guang

2014-01-01

In order to investigate the distribution characteristics of nutrients and heavy metals in sediments from different eastern dredging regions of Lake Taihu, the surface and core sediment samples at 5 sites (in East Taihu Lake and Xukou Bay) were collected in 2012. Contents of nutrients (TOC, TN and TP) and heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) in the sediments were measured and the pollution degrees of heavy metals were evaluated with the potential ecological risk method. The results showed that the heavy metal contents in Xukou Bay were generally higher than those in East Taihu Lake, whereas the nutrients contents showed the reverse trend. There were significant differences between the phytoplankton-dominated and culture lake regions. The concentrations of both nutrients and heavy metals decreased with increasing profile depth. Moreover, the contents of nutrients and heavy metals in the sediments of all dredged areas were lower than those in the un-dredged areas, suggesting that dredging may be a useful approach for decreasing nutrients and heavy metals loading in sediments, but its effectiveness decreased with time. Significant positive correlations were found among different heavy metals and nutrients, indicating that they were from the same pollution source. The Hakanson potential ecological risk index was applied for assessing the status of sediment heavy metal enrichment and the result indicated that sediment dredging could reduce the extent of potential ecological risk. The risk index in different sites followed the order: X1 > D1 > D3 > X2 > D2, while the risk index in site X1 of Xukou Bay was higher than that in site D1 of East Taihu Lake. And the comprehensive ecological risk grades in sites X1 and D1 were in the moderate range, while the sites D2, D3 and X2 were low.

Parasite infection alters nitrogen cycling at the ecosystem scale.

PubMed

Mischler, John; Johnson, Pieter T J; McKenzie, Valerie J; Townsend, Alan R

2016-05-01

Despite growing evidence that parasites often alter nutrient flows through their hosts and can comprise a substantial amount of biomass in many systems, whether endemic parasites influence ecosystem nutrient cycling, and which nutrient pathways may be important, remains conjectural. A framework to evaluate how endemic parasites alter nutrient cycling across varied ecosystems requires an understanding of the following: (i) parasite effects on host nutrient excretion; (ii) ecosystem nutrient limitation; (iii) effects of parasite abundance, host density, host functional role and host excretion rate on nutrient flows; and (iv) how this infection-induced nutrient flux compares to other pools and fluxes. Pathogens that significantly increase the availability of a limiting nutrient within an ecosystem should produce a measurable ecosystem-scale response. Here, we combined field-derived estimates of trematode parasite infections in aquatic snails with measurements of snail excretion and tissue stoichiometry to show that parasites are capable of altering nutrient excretion in their intermediate host snails (dominant grazers). We integrated laboratory measurements of host nitrogen excretion with field-based estimates of infection in an ecosystem model and compared these fluxes to other pools and fluxes of nitrogen as measured in the field. Eighteen nitrogen-limited ponds were examined to determine whether infection had a measurable effect on ecosystem-scale nitrogen cycling. Because of their low nitrogen content and high demand for host carbon, parasites accelerated the rate at which infected hosts excreted nitrogen to the water column in a dose-response manner, thereby shifting nutrient stoichiometry and availability at the ecosystem scale. Infection-enhanced fluxes of dissolved inorganic nitrogen were similar to other commonly important environmental sources of bioavailable nitrogen to the system. Additional field measurements within nitrogen-limited ponds indicated that nitrogen flux rates from the periphyton to the water column in high-snail density/high-infection ponds were up to 50% higher than low-infection ponds. By altering host nutrient assimilation/excretion flexibility, parasites could play a widespread, but currently unrecognized, role in ecosystem nutrient cycling, especially when parasite and host abundances are high and hosts play a central role in ecosystem nutrient cycling. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Guava Waste to Sustain Guava (Psidium guajava) Agroecosystem: Nutrient "Balance" Concepts.

PubMed

Souza, Henrique A; Parent, Serge-Étienne; Rozane, Danilo E; Amorim, Daniel A; Modesto, Viviane C; Natale, William; Parent, Leon E

2016-01-01

The Brazilian guava processing industry generates 5.5 M Mg guava waste year(-1) that could be recycled sustainably in guava agro-ecosystems as slow-release fertilizer. Our objectives were to elaborate nutrient budgets and to diagnose soil, foliar, and fruit nutrient balances in guava orchards fertilized with guava waste. We hypothesized that (1) guava waste are balanced fertilizer sources that can sustain crop yield and soil nutrient stocks, and (2) guava agroecosystems remain productive within narrow ranges of nutrient balances. A 6-year experiment was conducted in 8-year old guava orchard applying 0-9-18-27-36 Mg ha(-1) guava waste (dry mass basis) and the locally recommended mineral fertilization. Nutrient budgets were compiled as balance sheets. Foliar and fruit nutrient balances were computed as isometric log ratios to avoid data redundancy or resonance due to nutrient interactions and the closure to measurement unit. The N, P, and several other nutrients were applied in excess of crop removal while K was in deficit whatever the guava waste treatment. The foliar diagnostic accuracy reached 93% using isometric log ratios and knn classification, generating reliable foliar nutrient and concentration ranges at high yield level. The plant mined the soil K reserves without any significant effect on fruit yield and foliar nutrient balances involving K. High guava productivity can be reached at lower soil test K and P values than thought before. Parsimonious dosage of fresh guava waste should be supplemented with mineral K fertilizers to recycle guava waste sustainably in guava agroecosystems. Brazilian growers can benefit from this research by lowering soil test P and K threshold values to avoid over-fertilization and using fresh guava waste supplemented with mineral fertilizers, especially K. Because yield was negatively correlated with fruit acidity and Brix index, balanced plant nutrition and fertilization diagnosis will have to consider not only fruit yield targets but also fruit quality to meet requirements for guava processing.

Guava Waste to Sustain Guava (Psidium guajava) Agroecosystem: Nutrient “Balance” Concepts

PubMed Central

Souza, Henrique A.; Parent, Serge-Étienne; Rozane, Danilo E.; Amorim, Daniel A.; Modesto, Viviane C.; Natale, William; Parent, Leon E.

2016-01-01

The Brazilian guava processing industry generates 5.5 M Mg guava waste year−1 that could be recycled sustainably in guava agro-ecosystems as slow-release fertilizer. Our objectives were to elaborate nutrient budgets and to diagnose soil, foliar, and fruit nutrient balances in guava orchards fertilized with guava waste. We hypothesized that (1) guava waste are balanced fertilizer sources that can sustain crop yield and soil nutrient stocks, and (2) guava agroecosystems remain productive within narrow ranges of nutrient balances. A 6-year experiment was conducted in 8-year old guava orchard applying 0–9–18–27–36 Mg ha−1 guava waste (dry mass basis) and the locally recommended mineral fertilization. Nutrient budgets were compiled as balance sheets. Foliar and fruit nutrient balances were computed as isometric log ratios to avoid data redundancy or resonance due to nutrient interactions and the closure to measurement unit. The N, P, and several other nutrients were applied in excess of crop removal while K was in deficit whatever the guava waste treatment. The foliar diagnostic accuracy reached 93% using isometric log ratios and knn classification, generating reliable foliar nutrient and concentration ranges at high yield level. The plant mined the soil K reserves without any significant effect on fruit yield and foliar nutrient balances involving K. High guava productivity can be reached at lower soil test K and P values than thought before. Parsimonious dosage of fresh guava waste should be supplemented with mineral K fertilizers to recycle guava waste sustainably in guava agroecosystems. Brazilian growers can benefit from this research by lowering soil test P and K threshold values to avoid over-fertilization and using fresh guava waste supplemented with mineral fertilizers, especially K. Because yield was negatively correlated with fruit acidity and Brix index, balanced plant nutrition and fertilization diagnosis will have to consider not only fruit yield targets but also fruit quality to meet requirements for guava processing. PMID:27621735

Effect of nutrition education intervention based on Pender's Health Promotion Model in improving the frequency and nutrient intake of breakfast consumption among female Iranian students.

PubMed

Dehdari, Tahereh; Rahimi, Tahereh; Aryaeian, Naheed; Gohari, Mahmood Reza

2014-03-01

To determine the effectiveness of nutrition education intervention based on Pender's Health Promotion Model in improving the frequency and nutrient intake of breakfast consumption among female Iranian students. The quasi-experimental study based on Pender's Health Promotion Model was conducted during April-June 2011. Information (data) was collected by self-administered questionnaire. In addition, a 3 d breakfast record was analysed. P < 0·05 was considered significant. Two middle schools in average-income areas of Qom, Iran. One hundred female middle-school students. There was a significant reduction in immediate competing demands and preferences, perceived barriers and negative activity-related affect constructs in the experimental group after education compared with the control group. In addition, perceived benefit, perceived self-efficacy, positive activity-related affect, interpersonal influences, situational influences, commitment to a plan of action, frequency and intakes of macronutrients and most micronutrients of breakfast consumption were also significantly higher in the experimental group compared with the control group after the nutrition education intervention. Constructs of Pender's Health Promotion Model provide a suitable source for designing strategies and content of a nutrition education intervention for improving the frequency and nutrient intake of breakfast consumption among female students.

Nitrate losses, nutrients and heavy metal accumulation from substrates assembled for urban soils reconstruction.

PubMed

Civeira, G; Lavado, R S

2008-09-01

Urban soils may suffer mild to severe degradation as a result of physical and chemical alterations. To reconstruct these soils, a new upper horizon must be created, usually through the application of organic matter, one source of which is biosolids. Different soil mixtures were evaluated with regard to loss of nitrates in percolates and the uptake and incorporation of nutrients and heavy metals into plant tissues. The experiment was conducted in trays; treatments were mixtures of biosolids and a coarse material (e.g., sand or pine wood sawdust), combined in different proportions. Randomized trays were seeded with a mix of tall fescue (Festuca arundinacea L.) and perennial ryegrass (Lolium perenne L.). Plant biomass was quantified. Nitrates in percolates were measured, as were nutrients and heavy metals in mixtures and plant tissues. Plants accumulated substantially more N, and biomass was 40% higher, in the treatments with higher levels of biosolids. The same treatments released more nitrogen and resulted in higher percolate nitrate levels. Plants had normal concentrations of all nutrients, except nitrogen, which was low. Heavy metal concentrations were not significantly different among treatments. Based on the analysis of these data, the proportion of biosolids appears to be the most important factor affecting the quality of reconstructed soil and the rate of improvement. The type of coarse material used did not significantly affect the outcome.

Evaluating changes in water quality with respect to nonpoint source nutrient management strategies in the Chesapeake Bay Watershed

NASA Astrophysics Data System (ADS)

Keisman, J.; Sekellick, A.; Blomquist, J.; Devereux, O. H.; Hively, W. D.; Johnston, M.; Moyer, D.; Sweeney, J.

2014-12-01

Chesapeake Bay is a eutrophic ecosystem with periodic hypoxia and anoxia, algal blooms, diminished submerged aquatic vegetation, and degraded stocks of marine life. Knowledge of the effectiveness of actions taken across the watershed to reduce nitrogen (N) and phosphorus (P) loads to the bay (i.e. "best management practices" or BMPs) is essential to its restoration. While nutrient inputs from point sources (e.g. wastewater treatment plants and other industrial and municipal operations) are tracked, inputs from nonpoint sources, including atmospheric deposition, farms, lawns, septic systems, and stormwater, are difficult to measure. Estimating reductions in nonpoint source inputs attributable to BMPs requires compilation and comparison of data on water quality, climate, land use, point source discharges, and BMP implementation. To explore the relation of changes in nonpoint source inputs and BMP implementation to changes in water quality, a subset of small watersheds (those containing at least 10 years of water quality monitoring data) within the Chesapeake Watershed were selected for study. For these watersheds, data were compiled on geomorphology, demographics, land use, point source discharges, atmospheric deposition, and agricultural practices such as livestock populations, crop acres, and manure and fertilizer application. In addition, data on BMP implementation for 1985-2012 were provided by the Environmental Protection Agency Chesapeake Bay Program Office (CBPO) and the U.S. Department of Agriculture. A spatially referenced nonlinear regression model (SPARROW) provided estimates attributing N and P loads associated with receiving waters to different nutrient sources. A recently developed multiple regression technique ("Weighted Regressions on Time, Discharge and Season" or WRTDS) provided an enhanced understanding of long-term trends in N and P loads and concentrations. A suite of deterministic models developed by the CBPO was used to estimate expected nutrient load reductions attributable to BMPs. Further quantification of the relation of land-based nutrient sources and BMPs to water quality in the bay and its tributaries must account for inconsistency in BMP data over time and uncertainty regarding BMP locations and effectiveness.

Assessing possible visitor-use impacts on water quality in Yosemite National Park, California

USGS Publications Warehouse

Clow, David W.; Peavler, Rachael S.; Roche, Jim; Panorska, Anna K.; Thomas, James M.; Smith, Steve

2011-01-01

There is concern that visitor-use associated activities, such as bathing, dish washing, wastewater production, and stock animal use near lakes and streams, could cause degradation of water quality in Yosemite National Park. A study was conducted during 2004–2007 to assess patterns in nutrient and Escherichia coli (E. coli) concentrations in the Merced and Tuolumne Rivers and characterize natural background concentrations of nutrients in the park. Results indicated that nutrient and E. coli concentrations were low, even compared to other undeveloped sites in the United States. A multiple linear regression approach was used to model natural background concentrations of nutrients, with basin characteristics as explanatory variables. Modeled nitrogen concentrations increased with elevation, and modeled phosphorus concentrations increased with basin size. Observed concentrations (±uncertainty) were compared to modeled concentrations (±uncertainty) to identify sites that might be impacted by point sources of nutrients, as indicated by large model residuals. Statistically significant differences in observed and modeled concentrations were observed at only a few locations, indicating that most sites were representative of natural background conditions. The empirical modeling approach used in this study can be used to estimate natural background conditions at any point along a study reach in areas minimally impacted by development, and may be useful for setting water-quality standards in many national parks.

Sources and loads of nutrients in the South Platte River, Colorado and Nebraska, 1994-95

USGS Publications Warehouse

Litke, D.W.

1996-01-01

The South Platte River Basin was one of 20 river basins selected in 1991 for investigation as part of the U.S. Geological Survey's National Water- Quality Assessment (NAWQA) Program. Nationwide, nutrients have been identified as one of the primary nationwide water-quality concerns and are of particular interest in the South Platte River Basin where nutrient concentrations are large compared to concentrations in other NAWQA river basins. This report presents estimates of the magnitude of nutrient-source inputs to the South Platte River Basin, describes nutrient concen- trations and loads in the South Platte River during different seasons, and presents comparisons of nutrient inputs to instream nutrient loads. Annual nutrient inputs to the basin were estimated to be 306,000 tons of nitrogen and 41,000 tons of phosphorus. The principal nutrient sources were wastewater-treatment plants, fertilizer and manure applications, and atmospheric deposition. To characterize nutrient concentrations and loads in the South Platte River during different seasons, five nutrient synoptic samplings were conducted during 1994 and 1995. Upstream from Denver, Colorado, during April 1994 and January 1995, total nitrogen concentrations were less than 2 milligrams per liter (mg/L), and total phosphorus concentrations were less than 0.2 mg/L. The water in the river at this point was derived mostly from forested land in the mountains west of Denver. Total nutrient concentrations increased through the Denver metropolitan area, and concentration peaks occurred just downstream from each of Denver's largest wastewater-treatment plants with maximum concentrations of 13.6 mg/L total nitrogen and 2.4 mg/L total phosphorus. Nutrient concen- concentrations generally decreased downstream from Denver. Upstream from Denver during April 1994 and January 1995, total nitrogen loads were less than 1,000 pounds per day (lb/d), and total phosphorus loads were less than 125 lb/d. Total nutrient loads increased through the Denver metropolitan area, and load peaks occurred just downstream from each of Denver's largest wastewater-treatment plants, with a maximum load of 14,000 lb/d total nitrogen and 2,300 lb/d total phosphorus. In April 1994, nutrient loads generally decreased from Henderson, Colorado, to North Platte, Nebraska. In January 1995, however, nutrient loads increased from Henderson to Kersey, Colorado (maximum loads of 31,000 lb/d total nitrogen and 3,000 lb/d total phosphorus), and then decreased from Kersey to North Platte. Seasonal nutrient loads primarily were dependent on streamflow. Total nitrogen loads were largest in June 1994 and January 1995 when streamflows also were largest. During June, streamflow was large, but nitrogen concentrations were small, which indicated that snowmelt runoff diluted the available supply of nitrogen. Total phosphorus loads were largest in June, when streamflow and phosphorus concentrations were large, which indicated an additional source of phosphorus during snowmelt runoff. Streamflow along the South Platte River was smallest in April and August 1994, and nutrient loads also were smallest during these months. The downstream pattern for nutrient loads did not vary much by season. Loads were large at Henderson, decreased between Henderson and Kersey, and usually were largest at Kersey. The magnitude of the decrease in loads between Henderson and Kersey varied between synoptics and was dependent on the amount of water removed by irrigation ditches. Nutrient loads leaving the basin were very small compared to the estimated total nutrient inputs to the basin. Streamflow balances indicated that the South Platte River is a gaining river throughout much of its length; streamflow-balance residuals were as large as 15 cubic feet per second per mile. Nutrient-load balances indicated that increases in river nitrate loads were, in some places, due to nitrification and, elsewhere, were due to the influx of nitrate-enriched ground water to

Folate

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... on food sources of folate: U.S. Department of Agriculture's (USDA) National Nutrient Database Nutrient List for folate ( ...

Selenium

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... on food sources of selenium: U.S. Department of Agriculture's (USDA) National Nutrient Database Nutrient List for selenium ( ...

Calcium

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... on food sources of calcium: U.S. Department of Agriculture's (USDA) National Nutrient Database Nutrient List for calcium ( ...

Iron

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... on food sources of iron: U.S. Department of Agriculture's (USDA) National Nutrient Database Nutrient List for Iron ( ...

Magnesium

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... on food sources of magnesium: U.S. Department of Agriculture's (USDA) National Nutrient Database Nutrient List for magnesium ( ...

Are Seagrass effective Sentinels of Ecosystem Health in Port Phillip Bay, Australia?

NASA Astrophysics Data System (ADS)

Lee, R. S.; Cook, P. L. M.; Jenkins, G.; Nayar, S.; Hirst, A.; Keough, M. J.; Smith, T.; Ferguson, A.; Gay, J.; Longmore, A. R.; Macreadie, P.; Sherman, C.; Ross, J.; York, P.

2016-02-01

Seagrasses are an important part of many coastal systems, but are also under threat in many areas, as a result of a wide range of human activities, including habitat loss and changes to water quality. Due to these sensitivities seagrass are often selected as sentinels of change for coastal marine ecosystems, but could these sensitivities be too complex and varied to provide a clear or reliable measure of change? A recent three year study focused on the resilience of Zostera seagrasses in Port Phillip Bay, Southern Australia, where these ecosystem "engineers", have a dramatic influence on biodiversity and ecosystem function. This large temperate embayment experiences extreme climatic variability, significant loading from urbanized catchments and inflows from the largest sewage treatment facility in Australia, making it a challenging case study for assessing seagrass as a suitable ecosystem metric. Studies on the influence of nutrients, light and sediments using modelling, chemical analyses and field experiments assessed characteristics of Zostera habitat within the bay. Nutrients could be obtained directly in dissolved form from the water column, or sediment, or as atmospheric nitrogen fixed by bacteria associated with the root/rhizome system. Isotopic nutrients were traced to a variety of sources including river inflows, sewage discharges, groundwater, the open ocean, the atmosphere and indirectly via phytoplankton and detritus. Broad-scale seagrass coverage is often depth limited by light, however for regions of significant wave exposure deeper beds existed adjacent to less favorable shallows. Ephemeral beds in more exposed regions showed the greatest potential for responding to change. For these beds, resilience was dependent on bed architecture, connectivity to indirect nutrient sources, and genetic interactions with seagrass communities around the bay. While observed changes in seagrass cover may be a symptomatic trigger of ecosystem health, much as high blood pressure is to the human body, this study has shown that an understanding of the relative threats, system connectivity and co-dependencies of the more vulnerable communities can provide the most accurate account of ecosystem health.

The Fertile Grounds Initiative: A new way to close nutrient flows at regional level resulting in better agricultural productivity and less environmental losses

NASA Astrophysics Data System (ADS)

van Beek, Christy; van Duivenbooden, Niek; Noij, Gert-Jan

2014-05-01

The threat of declining soil fertility levels is well known. Yet, and despite numerous efforts, we seem incapable of changing the current situation of sink areas in developed countries and depletion areas in developing countries. With negative consequences (i.e. loss in productive capacity and loss in environmental quality) in both areas. Moreover, due to globalization and urbanization nutrient flows become increasingly disconnected. Soil nutrient depletion cannot simply be compensated for with mineral fertilisers, for the following reasons: • mineral fertilisers are often not affordable for smallholders and fertiliser subsidy systems are not always successful • mineral fertilisers do not contain organic matter and therefore do not halt the degradation of the soil • mineral fertilisers work best in combination with organic sources of nutrients (compost, farm yard manure, etc.) • To halt soil degradation an integrated approach is needed, including reducing losses of nutrients and organic matter from soils at risk. Presently, more actors are getting involved in reallocation of nutrients, especially in the energy and waste sector. Time has come for a new approach to bring together demands and supplies for nutrients. We therefore present the Fertile Grounds Initiative: a broker for nutrient supply and demand in the region. The Fertile Grounds Initiative is based on the findings that: • Organic ánd mineral nutrients are required for increased and sustainable production; • Nutrients have a value and should be treated as such; • Due to globalization and urbanization nutrient flows are ever more polarized between depletion and concentration areas; • The demand for energy poses new threats and opportunities for nutrient management. In the Fertile Grounds Initiative nutrient suppliers from the energy sector, waste management, fertilizer companies, etc. and demands for nutrients from farmers are brought together in a dynamic platform. This platform acts as a nutrient bank and integrates different sources of nutrients into high quality crop nutrition products. A capacity building programme ensures proper application of the nutrients and optimal use of on-farm nutrients. To further shape our ideas of the Fertile Grounds Initiative you are cordially invited to become involved.

Interactions of corn meal or molasses with a soybean-sunflower meal mix or flaxseed meal on production, milk fatty acids composition, and nutrient utilization in dairy cows fed grass hay-based diets

USDA-ARS?s Scientific Manuscript database

We investigated the interactions of molasses or corn meal [nonstructural carbohydrate (NSC) sources] with flaxseed meal or a soybean-sunflower meal protein mix [rumen-degradable protein (RDP) sources] on animal production, milk fatty acids profile, and nutrient utilization in organic Jersey cows fed...

Modeling nutrient sources, transport and management strategies in a coastal watershed, Southeast China.

PubMed

Zhou, Pei; Huang, Jinliang; Hong, Huasheng

2018-01-01

Integrated watershed management requires an analytical model capable of revealing the full range of impacts that would be caused by the uses and developments in the watershed. The SPAtially Referenced Regressions On Watershed Attributes (SPARROW) model was developed in this study to provide empirical estimates of the sources, transport of total nitrogen (TN) and total phosphorus (TP) and to develop nutrient management strategies in the Jiulong River Watershed, southeast China that has enormous influence on the region's ecological safety. We calibrated the model using data related to daily streamflow, monthly TN and TP concentrations in 2014 at 30 locations. The model produced R 2 values for TN with 0.95 and TP with 0.94. It was found that for the entire watershed, TN came from fertilizer application (43%), livestock breeding (39%) and sewage discharge (18%), while TP came from livestock breeding (46%), fertilizer application (46%), and industrial discharge (8%). Fifty-eight percent of the TN and 80% of the TP in upstream reaches are delivered to the outlets of North and West rivers. A scenario analysis with SPARROW was coupled to develop suitable management strategies. Results revealed that controlling nutrient sources was effective in improving water quality. Normally sharp reduction in nutrient sources is not operational feasible. Hence, it is recommended that preventing nutrient on land from entering into the river as a suitable strategy in watershed management. Copyright © 2017 Elsevier B.V. All rights reserved.

Production of ethanol from a mixture of waste paper and kitchen waste via a process of successive liquefaction, presaccharification, and simultaneous saccharification and fermentation.

PubMed

Nishimura, Hiroto; Tan, Li; Kira, Noriko; Tomiyama, Shigeo; Yamada, Kazuo; Sun, Zhao-Yong; Tang, Yue-Qin; Morimura, Shigeru; Kida, Kenji

2017-09-01

Efficient ethanol production from waste paper requires the addition of expensive nutrients. To reduce the production cost of ethanol from waste paper, a study on how to produce ethanol efficiently by adding kitchen waste (potentially as a carbon source, nutrient source, and acidity regulator) to waste paper was performed and a process of successive liquefaction, presaccharification, and simultaneous saccharification and fermentation (L+PSSF) was developed. The individual saccharification performances of waste paper and kitchen waste were not influenced by their mixture. Liquefaction of kitchen waste at 90°C prior to presaccharification and simultaneous saccharification and fermentation (PSSF) was essential for efficient ethanol fermentation. Ethanol at concentrations of 46.6 or 43.6g/l was obtained at the laboratory scale after fermentation for 96h, even without pH adjustment and/or the addition of extra nutrients. Similarly, ethanol at a concentration of 45.5g/l was obtained at the pilot scale after fermentation for 48h. The ethanol concentration of L+PSSF of the mixture of waste paper and kitchen waste was comparable to that of PSSF of waste paper with added nutrients (yeast extract and peptone) and pH adjustment using H 2 SO 4 , indicating that kitchen waste is not only a carbon source but also an excellent nutrient source and acidity regulator for fermentation of the mixture of waste paper and kitchen waste. Copyright © 2017. Published by Elsevier Ltd.

Sources and Delivery of Nutrients to the Northwestern Gulf of Mexico from Streams in the South-Central United States

USGS Publications Warehouse

Rebich, R.A.; Houston, N.A.; Mize, S.V.; Pearson, D.K.; Ging, P.B.; Evan, Hornig C.

2011-01-01

SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were developed to estimate nutrient inputs [total nitrogen (TN) and total phosphorus (TP)] to the northwestern part of the Gulf of Mexico from streams in the South-Central United States (U.S.). This area included drainages of the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf hydrologic regions. The models were standardized to reflect nutrient sources and stream conditions during 2002. Model predictions of nutrient loads (mass per time) and yields (mass per area per time) generally were greatest in streams in the eastern part of the region and along reaches near the Texas and Louisiana shoreline. The Mississippi River and Atchafalaya River watersheds, which drain nearly two-thirds of the conterminous U.S., delivered the largest nutrient loads to the Gulf of Mexico, as expected. However, the three largest delivered TN yields were from the Trinity River/Galveston Bay, Calcasieu River, and Aransas River watersheds, while the three largest delivered TP yields were from the Calcasieu River, Mermentau River, and Trinity River/Galveston Bay watersheds. Model output indicated that the three largest sources of nitrogen from the region were atmospheric deposition (42%), commercial fertilizer (20%), and livestock manure (unconfined, 17%). The three largest sources of phosphorus were commercial fertilizer (28%), urban runoff (23%), and livestock manure (confined and unconfined, 23%). ?? 2011 American Water Resources Association. This article is a U.S. Government work and is in the public domain in the USA.

The potential of freshwater macroalgae as a biofuels feedstock and the influence of nutrient availability on freshwater macroalgal biomass production

NASA Astrophysics Data System (ADS)

Yun, Jin-Ho

Extensive efforts have been made to evaluate the potential of microalgae as a biofuel feedstock during the past 4-5 decades. However, filamentous freshwater macroalgae have numerous characteristics that favor their potential use as an alternative algal feedstock for biofuels production. Freshwater macroalgae exhibit high rates of areal productivity, and their tendency to form dense floating mats on the water surface imply significant reductions in harvesting and dewater costs compared to microalgae. In Chapter 1, I reviewed the published literature on the elemental composition and energy content of five genera of freshwater macroalgae. This review suggested that freshwater macroalgae compare favorably with traditional bio-based energy sources, including terrestrial residues, wood, and coal. In addition, I performed a semi-continuous culture experiment using the common Chlorophyte genus Oedogonium to investigate whether nutrient availability can influence its higher heating value (HHV), productivity, and proximate analysis. The experimental study suggested that the most nutrient-limited growth conditions resulted in a significant increase in the HHV of the Oedogonium biomass (14.4 MJ/kg to 16.1 MJ/kg). Although there was no significant difference in productivity between the treatments, the average dry weight productivity of Oedogonium (3.37 g/m2/day) was found to be much higher than is achievable with common terrestrial plant crops. Although filamentous freshwater macroalgae, therefore, have significant potential as a renewable source of bioenergy, the ultimate success of freshwater macroalgae as a biofuel feedstock will depend upon the ability to produce biomass at the commercial-scale in a cost-effective and sustainable manner. Aquatic ecology can play an important role to achieve the scale-up of algal crop production by informing the supply rates of nutrients to the cultivation systems, and by helping to create adaptive production systems that are resilient to environmental change. In Chapter 2, I performed a review and an analysis of data from the published literature on the large-cultivation of freshwater macroalgae. This study revealed that the large-scale cultivation of freshwater macroalgae is feasible at relatively low cost using currently available technologies such as the Algal Turf Scrubber system (ATS). In addition, graphical analyses of published data obtained from ATS systems of varying sizes in operation worldwide revealed that both macroalgal biomass productivity and nutrient removal rates are hyperbolically related to the areal loading rates of both total nitrogen and total phosphorus. An assessment of the limited existing literature on carbon dioxide amendments suggested that the effectiveness and need for CO2 supplementation of macroalgal production systems like the ATS has not yet been conclusively demonstrated. Overall, this thesis demonstrates that filamentous freshwater macroalgae have great potential as a feedstock for both liquid and solid fuels, especially if nutrient-rich wastewater can be used as the supply of water and mineral nutrients. In addition, this thesis highlights the importance of studying the algal cultivation conditions that influence trade-offs between nutrient loading, biomass productivity, and biomass energy content. In particular, the hyperbolic relationship between algal biomass productivity and the areal loading rates of both total nitrogen and total phosphorus should provide critical insight when considering the production costs of macroalgal biomass at the commercial-scale.

Zinc

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... on food sources of zinc: U.S. Department of Agriculture's (USDA’s) National Nutrient Database Nutrient List for zinc ( ...

Vitamin E

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... food sources of vitamin E: U.S. Department of Agriculture's (USDA's) National Nutrient Database Nutrient List for vitamin ...

Vitamin C

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... food sources of vitamin C: U.S. Department of Agriculture's (USDA's) National Nutrient Database Nutrient List for vitamin ...

Vitamin D

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... food sources of vitamin D: U.S. Department of Agriculture's (USDA's) National Nutrient Database Nutrient List for vitamin ...

Vitamin A

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... food sources of vitamin A: U.S. Department of Agriculture's (USDA's) National Nutrient Database Nutrient List for vitamin ...

Nutrients and clam contamination by Escherichia coli in a meso-tidal coastal lagoon: Seasonal variation in counter cycle to external sources.

PubMed

Botelho, Maria João; Soares, Florbela; Matias, Domitília; Vale, Carlos

2015-07-15

The clam Ruditapes decussatus was transplanted from a natural recruitment area of Ria Formosa to three sites, surveyed for nutrients in water and sediments. Specimens were sampled monthly for determination of Escherichia coli, condition index and gonadal index. Higher nutrient values in low tide reflect drainage, anthropogenic sources or sediment regeneration, emphasising the importance of water mixing in the entire lagoon driven by the tide. Despite the increase of effluent discharges in summer due to tourism, nutrient concentrations and E. coli in clams were lower in warmer periods. The bactericide effect of temperature and solar radiation was better defined in clams from the inlet channel site than from sites closer to urban effluents. High temperature in summer and torrential freshwater inputs to Ria Formosa may anticipate climate change scenarios for south Europe. Seasonal variation of nutrients and clam contamination may thus point to possible alterations in coastal lagoons and their ecosystem services. Copyright © 2015. Published by Elsevier Ltd.

Temporal and spatial distributions of nutrients under the influence of human activities in Sishili Bay, northern Yellow Sea of China.

PubMed

Wang, Yujue; Liu, Dongyan; Dong, Zhijun; Di, Baoping; Shen, Xuhong

2012-12-01

The temporal and spatial distributions of dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON), soluble reactive phosphorus (SRP) and dissolved reactive silica (DRSi) together with chlorophyll-a, temperature and salinity were analyzed monthly from December 2008 to March 2010 at four zones in Sishili Bay located in the northern Yellow Sea. The nutrient distribution was impacted by seasonal factors (biotic factors, temperature and wet deposition), physical factors (water exchange) and anthropogenic loadings. The seasonal variations of nutrients were mainly determined by the seasonal factors and the spatial distribution of nutrients was mainly related to water exchange. Anthropogenic loadings for DIN, SRP and DRSi were mainly from point sources, but for DON, non-point sources were also important. Nutrient limitation has changed from DIN in 1997 to SRP and DRSi in 2010, and this has resulted in changes in the dominant red tide species from diatom to dinoflagellates. Copyright © 2012 Elsevier Ltd. All rights reserved.

Investigation of Carbon, Nutrients, and Groundwater Inputs in Coastal Florida Using Colored Dissolved Organic Matter

NASA Astrophysics Data System (ADS)

Arellano, A. R.; Coble, P. G.; Conmy, R. N.; Marine Spectrochemistry Group

2010-12-01

Very few studies of the exchange of water between aquifers and the ocean have been conducted along the Florida coast. Progression of residential and agricultural development in coastal areas is leading to increased nutrients from fertilizers and wastewaters to groundwater. A portion of these nutrients ultimately is released to coastal surface waters. Groundwater mining has increased salt water intrusions in coastal aquifers which may further enhance nutrient fluxes to coastal surface waters. Nutrient concentration in coastal groundwater is sometimes higher than those in river water, counterbalancing for the lower mass flux of groundwater relative to surface waters. Nutrient and carbon inputs through groundwater in certain areas may play an important role in cycling and primary productivity in the coastal ocean. King’s Bay is a spring-fed watershed and manatee sanctuary located on the West Florida Shelf. Over the past 25 years, springs supplying groundwater to King’s Bay have shown a three-fold increase in nitrate concentration and increased invasion of nuisance algae. It has been challenging to track sources of both nutrients and other water quality parameters because there are multiple water supplies to King’s Bay. The goal of this project is to improve the estimate of water, nutrients, and carbon from groundwater discharge into the coastal zone. This paper will present preliminary results of high resolution fluorescence spectroscopy analyses of the various source water types in the King's Bay watershed, including deep and shallow aquifers, wells, springs, and surface water sources. Samples were obtained from various sites--5 springs, 27 wells, 12 surface, and 9 lakes and rivers-- within the King’s Bay area during one dry season. Lakes and rivers had the highest fluorescence intensities and showed similar composition, with the most red-shifted emission maxima. Second highest concentration was seen in some of the wells which had wide range in both composition and intensities. King’s Bay surface sites appear to be a mixture of surface water and spring water based on both composition and concentration. Springs samples were all similar in composition, with concentrations in middle range found in well samples. These results will be discussed in reference to determination of source of water, carbon, and nutrients to the springs.

Nutrient removal by prairie filter strips in agricultural landscapes

Treesearch

X. Zhou; M.J. Helmers; H. Asbjornsen; R. Kolka; M.D. Tomer; R.M. Cruse

2014-01-01

Nitrogen (N) and phosphorus (P) from agricultural landscapes have been identified as primary sources of excess nutrients in aquatic systems. The main objective of this study was to evaluate the effectiveness of prairie filter strips (PFS) in removing nutrients from cropland runoff in 12 small watersheds in central Iowa. Four treatments with PFS of different spatial...

Fungal nutrient allocation in common mycorrhizal networks is regulated by the carbon source strength of individual host plants

USDA-ARS?s Scientific Manuscript database

• The common mycorrhizal networks (CMN) of arbuscular mycorrhizal (AM) fungi in the soil provide multiple host plants with nutrients, but the mechanisms by which the nutrient transport to individual host plants within one CMN is controlled, are currently unknown. • We followed by radioactive and st...

Effects of processing methods on nutrient and antinutrient composition of yellow yam (Dioscorea cayenensis) products.

PubMed

Adepoju, Oladejo Thomas; Boyejo, Oluwatosin; Adeniji, Paulina Olufunke

2018-01-01

There is dearth of documented information on nutrient retention of Dioscorea cayenensis products. This study was carried out to evaluate effects of processing methods on nutrient and antinutrient retention of yellow yam products. Fresh Dioscorea cayenensis tubers were purchased from Bodija market in Ibadan, peeled, cut into small pieces, divided into nine portions. One portion was treated as raw sample, and others processed into local delicacies. All nine samples were analysed for proximate, mineral, vitamin and antinutrient composition using AOAC methods. Data were analysed using ANOVA at p=0.05. Raw yam contained 66.79g moisture, 2.62g crude protein, 0.27g lipid, 0.17g fibre, 0.63g ash, 29.69g carbohydrates, 262.30mg potassium, 61.53mg magnesium, 0.79mg iron, 0.39mg zinc, and yielded 108.26kcal energy with insignificant vitamin content/100g edible portion. Processing significantly improved macronutrients and energy content with significant reduction in all antinutrients of products (p<0.05). The yam products can serve as staple source of energy to consumers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nitrogen isotope and mass balance approach in the Elbe Estuary

NASA Astrophysics Data System (ADS)

Sanders, Tina; Wankel, Scott D.; Dähnke, Kirstin

2017-04-01

The supply of bioavailable nitrogen is crucial to primary production in the world's oceans. Especially in estuaries, which act as a nutrient filter for coastal waters, microbial nitrogen turnover and removal has a particular significance. Nitrification as well as other nitrogen-based processes changes the natural abundance of the stable isotope, which can be used as proxies for sources and sinks as well as for process identification. The eutrophic Elbe estuary in northern Germany is loaded with fertilizer-derived nitrogen, but management efforts have started to reduce this load effectively. However, an internal nitrate source in turn gained in importance and the estuary changed from a sink to a source of dissolved inorganic nitrogen: Nitrification is responsible for significant estuarine nutrient regeneration, especially in the Hamburg Port. In our study, we aimed to quantify sources and sinks of nitrogen based on a mass and stable isotope budget in the Elbe estuary. A model was developed reproduce internal N-cycling and associated isotope changes. For that approach we measured dissolved inorganic nitrogen (DIN), particulate nitrogen and their stable isotopes in a case study in July 2013. We found an almost closed mass balance of nitrogen, with only low lost or gains which we attribute to sediment resuspension. The isotope values of different DIN components and the model approach both support a high fractionation of up to -25‰ during nitrification. However, the nitrogen balance and nitrogen stable isotopes suggest that most important processes are remineralization of organic matter to ammonium and further on the oxidation to nitrate. Denitrification and nitrate assimilation play a subordinate role in the Elbe Estuary.

Using mushroom farm and anaerobic digestion wastewaters as supplemental fertilizer sources for growing container nursery stock in a closed system.

PubMed

Chong, C; Purvis, P; Lumis, G; Holbein, B E; Voroney, R P; Zhou, H; Liu, H-W; Alam, M Z

2008-04-01

Wastewaters from farm and composting operations are often rich in select nutrients that potentially can be reutilized in crop production. Liners of silverleaf dogwood (Cornus alba L. 'Argenteo-marginata'), common ninebark [Physocarpus opulifolius (L.) Maxim.], and Anthony Waterer spirea (Spiraeaxbumalda Burvénich 'Anthony Waterer') were grown in 6L containers filled with a bark-based commercial mix. Plants were fertigated daily via a computer-controlled multi-fertilizer injector with three recirculated fertilizer treatments: (1) a stock (control) solution with complete macro- and micro-nutrients, electrical conductivity (EC) 2.2 dS m(-1); (2) wastewater from a mushroom farm; and (3) process wastewater from anaerobic digestion of municipal solid waste. The wastewaters used in both treatments 2 and 3 were diluted with tap water, and the computer was programmed to amend, dispense and recirculate nutrients based on the same target EC as in treatment 1. For comparison, there was a traditional controlled-release fertilizer treatment [Nutryon 17-5-12 (17N-2P-10K) plus micro-nutrients topdressed at a rate of 39 g/plant, nutrients not recirculated]. All three species responded similarly to the three recirculated fertilizer treatments. Growth with the recirculated treatments was similar and significantly higher than that obtained with controlled-release fertilizer. Throughout the study, the EC measured in wastewater-derived nutrient solutions, and also in the container substrate, were similar or close to those of the control treatment, although there were small to large differences among individual major nutrients. There was no sign of nutrient deficiency or toxicity symptoms to the plants. Small to moderate excesses in concentrations of SO(4), Na, and/or Cl were physiologically tolerable to the species.

Effects of pulsed nutrient inputs on phytoplankton assemblage structure and blooms in an enclosed coastal area

NASA Astrophysics Data System (ADS)

Spatharis, Sofie; Tsirtsis, George; Danielidis, Daniel B.; Chi, Thang Do; Mouillot, David

2007-07-01

The response of phytoplankton assemblage structure to terrestrial nutrient inputs was examined for the Gulf of Kalloni in the Northern Aegean Sea, a productive semi-enclosed coastal marine ecosystem. The study was focused on a typical annual cycle, and emphasis was placed on the comparative analysis between blooms developing after significant nutrient inputs from the watershed, and naturally occurring blooms. Baseline information was collected on a monthly basis from a network of stations located in the oligotrophic open sea and the interior and more productive part of the embayment. Intensive sampling was also carried out along a gradient in the vicinity of a river which was the most important source of freshwater and nutrient input for the Gulf. Phytoplankton assemblage structure was analyzed from 188 samples using diversity indices (Shannon and Average Taxonomic Distinctness), multivariate plotting methods (NMDS), multivariate statistics (PERMANOVA), and canonical correspondence analysis (CCA). Three characteristic assemblages were recognized: (1) an autumn assemblage developed under nutrient depleted conditions, having low diversity due to the dominance of two small diatoms, (2) a winter bloom of the potentially toxic species Pseudo-nitzschia calliantha occurring immediately after a nutrient peak and characterized by very low diversity, and (3) a naturally occurring early summer bloom of centric diatoms with relatively high diversity. The results of the study support the view that moderate nutrient inputs may have a beneficial effect on the functioning of coastal ecosystems, stimulating the taxonomic diversity through the growth of different taxonomic groups and taxa. On the other hand, a sudden pulse of high nutrient concentrations may greatly affect the natural succession of organisms, have a negative effect on the diversity through the dominance of a single species, and can increase the possibility of a harmful algal bloom development.

Potassium

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture’s MyPlate . Where can I find out more about ... on food sources of potassium: U.S. Department of Agriculture’s (USDA) National Nutrient Database Nutrient List for potassium ( ...

Vitamin B6

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... food sources of vitamin B6: U.S. Department of Agriculture's (USDA's) National Nutrient Database Nutrient List for vitamin ...

Vitamin B12

MedlinePlus

... Guidelines for Americans and the U.S. Department of Agriculture's MyPlate . Where can I find out more about ... food sources of vitamin B12: U.S. Department of Agriculture's (USDA's) National Nutrient Database Nutrient List for vitamin ...

Selected nutrients and pesticides in streams of the eastern Iowa basins, 1970-95

USGS Publications Warehouse

Schnoebelen, Douglas J.; Becher, Kent D.; Bobier, Matthew W.; Wilton, Thomas

1999-01-01

 The statistical analysis of the nutrient data typically indicated a strong positive correlation of nitrate with streamflow. Total phosphorus concentrations with streamflow showed greater variability than nitrate, perhaps reflecting the greater potential of transport of phosphorus on sediment rather than in the dissolved phase as with nitrate. Ammonia and ammonia plus organic nitrogen showed no correlation with streamflow or a weak positive correlation. Seasonal variations and the relations of nutrients and pesticides to streamflow generally corresponded with nonpoint‑source loadings, although possible point sources for nutrients were indicated by the data at selected monitoring sites. Statistical trend tests for concentrations and loads were computed for nitrate, ammonia, and total phosphorus. Trend analysis indicated decreases for ammonia and total phosphorus concentrations at several sites and increases for nitrate concentrations at other sites in the study unit.

Human Geophagia, Calabash Chalk and Undongo: Mineral Element Nutritional Implications

PubMed Central

Abrahams, Peter W.; Davies, Theo C.; Solomon, Abiye O.; Trow, Amanda J.; Wragg, Joanna

2013-01-01

The prime aim of our work is to report and comment on the bioaccessible concentrations – i.e., the soluble content of chemical elements in the gastrointestinal environment that is available for absorption – of a number of essential mineral nutrients and potentially harmful elements (PHEs) associated with the deliberate ingestion of African geophagical materials, namely Calabash chalk and Undongo. The pseudo-total concentrations of 13 mineral nutrients/PHEs were quantified following a nitric-perchloric acid digestion of nine different Calabash chalk samples, and bioaccessible contents of eight of these chemical elements were determined in simulated saliva/gastric and intestinal solutions obtained via use of the Fed ORganic Estimation human Simulation Test (FOREhST) in vitro procedure. The Calabash chalk pseudo-total content of the chemical elements is often below what may be regarded as average for soils/shales, and no concentration is excessively high. The in vitro leachate solutions had concentrations that were often lower than those of the blanks used in our experimental procedure, indicative of effective adsorption: lead, a PHE about which concern has been previously raised in connection with the consumption of Calabash chalk, was one such chemical element where this was evident. However, some concentrations in the leachate solutions are suggestive that Calabash chalk can be a source of chemical elements to humans in bioaccessible form, although generally the materials appear to be only a modest supplier: this applies even to iron, a mineral nutrient that has often been linked to the benefits of geophagia in previous academic literature. Our investigations indicate that at the reported rates of ingestion, Calabash chalk on the whole is not an important source of mineral nutrients or PHEs to humans. Similarly, although Undongo contains elevated pseudo-total concentrations of chromium and nickel, this soil is not a significant source to humans for any of the bioaccessible elements investigated. PMID:23308189

Wool-waste as organic nutrient source for container-grown plants

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

Zheljazkov, Valtcho D.; Stratton, Glenn W.; Pincock, James

A container experiment was conducted to test the hypothesis that uncomposted wool wastes could be used as nutrient source and growth medium constituent for container-grown plants. The treatments were: (1) rate of wool-waste application (0 or unamended control, 20, 40, 80, and 120 g of wool per 8-in. pot), (2) growth medium constituents [(2.1) wool plus perlite, (2.2) wool plus peat, and (2.3) wool plus peat plus perlite], and (3) plant species (basil and Swiss chard). A single addition of 20, 40, 80, or 120 g of wool-waste to Swiss chard (Beta vulgaris L.) and basil (Ocimum basilicum L.) inmore » pots with growth medium provided four harvests of Swiss chard and five harvests of basil. Total basil yield from the five harvests was 1.6-5 times greater than the total yield from the unamended control, while total Swiss chard yield from the four harvests was 2-5 times greater relative to the respective unamended control. The addition of wool-waste to the growth medium increased Swiss chard and basil tissue N, and NO{sub 3}-N and NH{sub 4}-N in growth medium relative to the unamended control. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) microanalysis of wool fibers sampled at the end of the experiments indicated various levels of decomposition, with some fibers retaining their original surface structure. Furthermore, most of the wool fibers' surfaces contained significant concentrations of S and much less N, P, or K. SEM/EDX revealed that some plant roots grow directly on wool-waste fibers suggesting either (1) root directional growth towards sites with greater nutrient concentration and/or (2) a possible role for roots or root exudates in wool decomposition. Results from this study suggest that uncomposted wool wastes can be used as soil amendment, growth medium constituent, and nutrient source for container-grown plants.« less

Human geophagia, calabash chalk and undongo: mineral element nutritional implications.

PubMed

Abrahams, Peter W; Davies, Theo C; Solomon, Abiye O; Trow, Amanda J; Wragg, Joanna

2013-01-01

The prime aim of our work is to report and comment on the bioaccessible concentrations - i.e., the soluble content of chemical elements in the gastrointestinal environment that is available for absorption - of a number of essential mineral nutrients and potentially harmful elements (PHEs) associated with the deliberate ingestion of African geophagical materials, namely Calabash chalk and Undongo. The pseudo-total concentrations of 13 mineral nutrients/PHEs were quantified following a nitric-perchloric acid digestion of nine different Calabash chalk samples, and bioaccessible contents of eight of these chemical elements were determined in simulated saliva/gastric and intestinal solutions obtained via use of the Fed ORganic Estimation human Simulation Test (FOREhST) in vitro procedure. The Calabash chalk pseudo-total content of the chemical elements is often below what may be regarded as average for soils/shales, and no concentration is excessively high. The in vitro leachate solutions had concentrations that were often lower than those of the blanks used in our experimental procedure, indicative of effective adsorption: lead, a PHE about which concern has been previously raised in connection with the consumption of Calabash chalk, was one such chemical element where this was evident. However, some concentrations in the leachate solutions are suggestive that Calabash chalk can be a source of chemical elements to humans in bioaccessible form, although generally the materials appear to be only a modest supplier: this applies even to iron, a mineral nutrient that has often been linked to the benefits of geophagia in previous academic literature. Our investigations indicate that at the reported rates of ingestion, Calabash chalk on the whole is not an important source of mineral nutrients or PHEs to humans. Similarly, although Undongo contains elevated pseudo-total concentrations of chromium and nickel, this soil is not a significant source to humans for any of the bioaccessible elements investigated.

Recapturing nutrients from dairy waste using biochar

NASA Astrophysics Data System (ADS)

Sarkhot, D.; Ghezzehei, T. A.; Berhe, A. A.

2009-12-01

Biochar or biomass derived black carbon is known to be highly resistant to decomposition with half-life periods ranging from hundreds of years to millennia. It is also reported to enhance soil productivity due to high nutrient retention and favorable effects on soil pH, water retention capacity as well as microbial population. Brazilian Terra Preta soils have shown the potential of biochar for long-term carbon sequestration capacity and productivity of soil and many researchers have now focused on utilizing this phenomenon to create fertile, carbon-rich soils, called Terra Preta Nova. Although the highly adsorptive nature of biochar is well characterized, the potential for using biochar in environmental cleanup efforts is relatively unexplored. Dairy waste is a source of significant water pollution because it introduces excess nutrients such as phosphates and nitrates into the soil and water system. Since many soils have limited capacity to retain nitrate and phosphate, especially for long periods of time, the utility of dairy waste manure to enhance soil fertility and nutrient availability to plants is limited. Here, we present results from a project that we started to determine the potential of biochar to recover the excess nutrients from dairy flushed manure. In this initial study, a commercially available biochar amendment was ground and used in a batch sorption experiment with the dairy flushed manure from a local dairy in Merced, California. Four manure dilutions viz. 10, 25, 50 and 100%, and three shaking times, viz. 1, 12 and 24 hours were used for this study. We then calculated the amount of ammonia, nitrate and phosphate adsorbed by the biochar using differences in nutrient concentrations before and after the sorption experiment. Biochar showed significant capacity of adsorbing these nutrients, suggesting a potential for controlling the dairy pollution. The resulting enriched biochar can potentially act as a slow release fertilizer and enhance soil productivity as well as increasing the long-term carbon sequestration potential of soils. We are currently initiating further research to determine the desorption potenial of the biochar sorbed nutrients in soil.

Growth of mono- and mixed cultures of Nannochloropsis salina and Phaeodactylum tricornutum on struvite as a nutrient source

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

Davis, Ryan W.; Siccardi, Anthony J.; Huysman, Nathan D.

In this paper, the suitability of crude and purified struvite (MgNH 4PO 4), a major precipitate in wastewater streams, was investigated for renewable replacement of conventional nitrogen and phosphate resources for cultivation of microalgae. Bovine effluent wastewater stone, the source of crude struvite, was characterized for soluble N/P, trace metals, and biochemical components and compared to the purified mineral. Cultivation trials using struvite as a major nutrient source were conducted using two microalgae production strains, Nannochloropsis salina and Phaeodactylum tricornutum, in both lab and outdoor pilot-scale raceways in a variety of seasonal conditions. Both crude and purified struvite-based media weremore » found to result in biomass productivities at least as high as established media formulations (maximum outdoor co-culture yield ~20 ± 4 g AFDW/m 2/day). Finally, analysis of nutrient uptake by the alga suggest that struvite provides increased nutrient utilization efficiency, and that crude struvite satisfies the trace metals requirement and results in increased pigment productivity for both microalgae strains.« less

Nutrient loading and selected water-quality and biological characteristics of Dickinson Bayou near Houston, Texas, 1995-97

USGS Publications Warehouse

East, Jeffery W.; Paul, Edna M.; Porter, Stephen D.

1998-01-01

Algal samples were collected at seven stations and were analyzed for periphyton identification and enumeration, and chlorophyll a and chlorophyll b concentrations. The large relative abundance of soil algae at stations in the middle of the watershed likely indicates the cumulative effects on water quality of agricultural nonpoint sources. Farther downstream near the State Highway 3 bridge, and downstream of three major tributary inflows, the increase in abundance of soil algae to a larger-than-expected level might reflect water-quality influences from predominantly urban nonpoint sources in the drainage basins of the three major tributary inflows. Nutrient concentrations do not appear to limit algal production in the upper (non-tidal) reach of Dickinson Bayou; but nutrient concentrations could have been limiting benthicalgal production in the lower (tidal) reach of the bayou during the time of the synoptic survey. If nitrogen is the limiting resource for algal productivity in the tidal reach of Dickinson Bayou, eutrophication of the system could be (at least partially) mitigated if nonpoint-source nutrient loads into the Bayou were reduced. 

Source-separated urine opens golden opportunities for microbial electrochemical technologies.

PubMed

Ledezma, Pablo; Kuntke, Philipp; Buisman, Cees J N; Keller, Jürg; Freguia, Stefano

2015-04-01

The food security of a booming global population demands a continuous and sustainable supply of fertilisers. Their current once-through use [especially of the macronutrients nitrogen (N), phosphorus (P), and potassium (K)] requires a paradigm shift towards recovery and reuse. In the case of source-separated urine, efficient recovery could supply 20% of current macronutrient usage and remove 50-80% of nutrients present in wastewater. However, suitable technology options are needed to allow nutrients to be separated from urine close to the source. Thus far none of the proposed solutions has been widely implemented due to intrinsic limitations. Microbial electrochemical technologies (METs) have proved to be technically and economically viable for N recovery from urine, opening the path for novel decentralised systems focused on nutrient recovery and reuse. Copyright © 2015 Elsevier Ltd. All rights reserved.

Carbon Cycle in South China Sea: Flux, Controls and Global Implications

NASA Astrophysics Data System (ADS)

Dai, M.; Cao, Z.; Yang, W.; Guo, X.; Yin, Z.; Gan, J.

2016-12-01

The contemporary coastal ocean is generally seen as a significant CO2 sink of 0.2-0.4 Pg C/yr at the global scale. However, mechanistic understanding of the coastal ocean carbon cycle remains limited, leading to the unanswered question of why some coastal systems are sources while others are sinks of atmospheric CO2. As the largest marginal sea of Northern Pacific, the South China Sea (SCS) is a mini-ocean with wide shelves in both its southern and northern parts. Its northern shelf, which receives significant land inputs from the Pearl River, a world major river, can be categorized as a River-Dominated Margin (RioMar) during peak discharges, and is characterized as a CO2 sink to the atmosphere. The SCS basin is identified as an Ocean-Dominated Margin (OceMar) and a CO2 source. OceMar is characterized by exchange with the open ocean via a two-dimensional (at least) process, i.e., the horizontal intrusion of open ocean water and subsequent vertical mixing and upwelling. Depending on the different ratios of dissolved inorganic carbon (DIC) and nutrients from the source waters into the continental margins, the relative consumption or removal bwtween DIC and nutrients, when being transported into the euphotic zones where biogeochemical processes take over, determines the CO2 fluxes. Thus, excess DIC relative to nutrients existing in the upper layer will lead to CO2 degassing. The CO2 fluxes in both RioMars and OceMars can be quantified using a semi-analytical diagnostic approach by coupling the physical dynamics and biogeochemical processes. We extended our mechanistic studies in the SCS to other OceMars including the Caribbean Sea, the Arabian Sea, and the upwelling system off the Oregon-California coast, and RioMars including the East China Sea and Amazon River plume to demonstrate the global implications of our SCS carbon studies.

Common Prairie feeds with different soluble and insoluble fractions used for CPM diet formulation in dairy cattle: impact of carbohydrate-protein matrix structure on protein and other primary nutrient digestion.

PubMed

Peng, Quanhui; Wang, Zhisheng; Zhang, Xuewei; Yu, Peiqiang

2014-01-01

An experiment was conducted to investigate the relationship of carbohydrates molecular spectral characteristics to rumen degradability of primary nutrients in Prairie feeds in dairy cattle. In total, 12 different types of feeds were selected, each type of feed was from three different source with total 37 samples. Six types of them were energy-sourced feeds and the others were protein-sourced feeds. The carbohydrates molecular spectral intensity of various functional groups were collected using Fourier transform infrared attenuated total reflectance (ATR-FT/IR) spectroscopy. In the in situ study, the results showed that the rumen digestibility and digestible fractions of primary nutrients (DM, OM, NCP, and CP) were significantly different (P<0.05) among the feeds. The spectral bands features were significantly different (P<0.05) among the feeds. Spectral intensities of A_Cell, H_1415 and H_1370 were weakly positively correlated with in situ rumen digestibility and digestible fractions of DM, OM and NCP. Spectral intensities of H_1150, H_1015, A_1, and A_3 were weakly negatively associated with in situ rumen degradation of CP. Spectral intensities of A_1240 and H_1240, mainly associated with cellulosic compounds, were correlated with rumen CP degradation. The multiple regression analysis demonstrated that the spectral intensities of A_3 and H_1415 played the most important role and could be used as a potential tool to predict rumen protein degradation of feeds in dairy cattle. In conclusion, this study showed that the carbohydrates as a whole have an effect on protein rumen degradation, rather than cellulose alone, indicating carbohydrate-protein matrix structure impact protein utilization in dairy cattle. The non-invasive molecular spectral technique (ATR-FT/IR) could be used as a rapid potential tool to predict rumen protein degradation of feedstuffs by using molecular spectral bands intensities in carbohydrate fingerprint region. Copyright © 2013 Elsevier B.V. All rights reserved.

Vulnerability of Coral Reefs to Bioerosion From Land-Based Sources of Pollution

NASA Astrophysics Data System (ADS)

Prouty, Nancy G.; Cohen, Anne; Yates, Kimberly K.; Storlazzi, Curt D.; Swarzenski, Peter W.; White, Darla

2017-12-01

Ocean acidification (OA), the gradual decline in ocean pH and [CO32-] caused by rising levels of atmospheric CO2, poses a significant threat to coral reef ecosystems, depressing rates of calcium carbonate (CaCO3) production, and enhancing rates of bioerosion and dissolution. As ocean pH and [CO32-] decline globally, there is increasing emphasis on managing local stressors that can exacerbate the vulnerability of coral reefs to the effects of OA. We show that sustained, nutrient rich, lower pH submarine groundwater discharging onto nearshore coral reefs off west Maui lowers the pH of seawater and exposes corals to nitrate concentrations 50 times higher than ambient. Rates of coral calcification are substantially decreased, and rates of bioerosion are orders of magnitude higher than those observed in coral cores collected in the Pacific under equivalent low pH conditions but living in oligotrophic waters. Heavier coral nitrogen isotope (δ15N) values pinpoint not only site-specific eutrophication, but also a sewage nitrogen source enriched in 15N. Our results show that eutrophication of reef seawater by land-based sources of pollution can magnify the effects of OA through nutrient driven-bioerosion. These conditions could contribute to the collapse of coastal coral reef ecosystems sooner than current projections predict based only on ocean acidification.