Science.gov

Sample records for limited water annual

  1. [Plant growth with limited water]. [Annual report, December 15, 1992--December 14, 1993

    SciTech Connect

    Not Available

    1993-12-01

    We used a soybean seedling system to explore the mechanism of growth limitation by water deficiency (low {Psi}{sub W}). Our prior work had show that (low {Psi}{sub W} inhibited plant growth initially because of a physical limitation to water uptake that appeared to result from a decrease in the {Psi}{sub W} gradient feeding water to the enlarging cells. The gradient was shown to originate from cell wall yielding and was altered primarily at the vascular tissue. In the present grant, we reported the detailed shape of the gradient. We also found that growth could mobilize water from mature tissues in the complete absence of external water using the gradient in {Psi}{sub W}. Growth was maintained by this mobilization. After growth has been inhibited a few hours, metabolic changes occur and a 28kD protein accumulates in the wall fraction of the growth-affected cells. In the present grant, we showed that the mRNA for the protein accumulated in a tissue-specific manner similar to that of the protein, and the accumulation was correlated with the growth response. Other investigators working independently with an acid phosphatase found a deduced amino acid sequence similar to that for the 28kD protein we had published. Biochemical tests showed that the 28kD protein and a related 3lkD protein expressed acid phosphatase activity. We found that the acid phosphatase Of the 28kD protein was in the cell walls of intact plants (in addition to being in the cytoplasm). Current work focuses on the role of this protein. Efforts were made to reverse the growth inhibition at low {Phi}{sub W} by treating growing tissues with low pH buffer, but the protons apparently failed to penetrate the cuticle.

  2. The effect of limited availability of N or water on C allocation to fine roots and annual fine root turnover in Alnus incana and Salix viminalis.

    PubMed

    Rytter, Rose-Marie

    2013-09-01

    The effect of limited nitrogen (N) or water availability on fine root growth and turnover was examined in two deciduous species, Alnus incana L. and Salix viminalis L., grown under three different regimes: (i) supply of N and water in amounts which would not hamper growth, (ii) limited N supply and (iii) limited water supply. Plants were grown outdoors during three seasons in covered and buried lysimeters placed in a stand structure and filled with quartz sand. Computer-controlled irrigation and fertilization were supplied through drip tubes. Production and turnover of fine roots were estimated by combining minirhizotron observations and core sampling, or by sequential core sampling. Annual turnover rates of fine roots <1 mm (5-6 year(-1)) and 1-2 mm (0.9-2.8 year(-1)) were not affected by changes in N or water availability. Fine root production (<1 mm) differed between Alnus and Salix, and between treatments in Salix; i.e., absolute length and biomass production increased in the order: water limited < unlimited < N limited. Few treatment effects were detected for fine roots 1-2 mm. Proportionally more C was allocated to fine roots (≤2 mm) in N or water-limited Salix; 2.7 and 2.3 times the allocation to fine roots in the unlimited regime, respectively. Estimated input to soil organic carbon increased by ca. 20% at N limitation in Salix. However, future studies on fine root decomposition under various environmental conditions are required. Fine root growth responses to N or water limitation were less pronounced in Alnus, thus indicating species differences caused by N-fixing capacity and slower initial growth in Alnus, or higher fine root plasticity in Salix. A similar seasonal growth pattern across species and treatments suggested the influence of outer stimuli, such as temperature and light.

  3. USGS Annual Water Data Reports

    SciTech Connect

    2012-04-01

    Water resources data are published annually for use by engineers, scientists, managers, educators, and the general public. These archival products supplement direct access to current and historical water data provided by the National Water Information System (NWIS). Beginning with Water Year 2006, annual water data reports are available as individual electronic Site Data Sheets for the entire Nation for retrieval, download, and localized printing on demand. National distribution includes tabular and map interfaces for search, query, display and download of data. Data provided include extreme and mean discharge rates.

  4. Drinking Water Program 1992 annual report

    SciTech Connect

    Andersen, B.D.; Peterson-Wright, L.J.

    1993-08-01

    EG&G Idaho, Inc., initiated a monitoring program for drinking water in 1988 for the US Department of Energy at the Idaho National Engineering Laboratory. EG&G Idaho structured this monitoring program to ensure that they exceeded the minimum regulatory requirements for monitoring drinking water. This program involves tracking the bacteriological, chemical, and radiological parameters that are required for a {open_quotes}community water system{close_quotes} (maximum requirements). This annual report describes the drinking water monitoring activities conducted at the 17 EG&G Idaho operated production wells and 11 distribution systems. It also contains all of the drinking water parameters that were detected and the regulatory limits that were exceeded during 1992. In addition, ground water quality is discussed as it relates to contaminants identified at the wellhead for EG&G Idaho production wells.

  5. 20 CFR 404.1047 - Annual wage limitation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....1047 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS AND DISABILITY... wage limitation. Payments made by an employer to you as an employee in a calendar year that are more than the annual wage limitation are not wages. The annual wage limitation is: Calendar year...

  6. 39 CFR 3010.21 - Calculation of annual limitation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Calculation of annual limitation. 3010.21 Section 3010.21 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL REGULATION OF RATES FOR MARKET DOMINANT PRODUCTS Rules for Applying the Price Cap § 3010.21 Calculation of annual limitation. (a) The...

  7. Modeling Limited Foresight in Water Management Systems

    NASA Astrophysics Data System (ADS)

    Howitt, R.

    2005-12-01

    The inability to forecast future water supplies means that their management inevitably occurs under situations of limited foresight. Three modeling problems arise, first what type of objective function is a manager with limited foresight optimizing? Second how can we measure these objectives? Third can objective functions that incorporate uncertainty be integrated within the structure of optimizing water management models? The paper reviews the concepts of relative risk aversion and intertemporal substitution that underlie stochastic dynamic preference functions. Some initial results from the estimation of such functions for four different dam operations in northern California are presented and discussed. It appears that the path of previous water decisions and states influences the decision-makers willingness to trade off water supplies between periods. A compromise modeling approach that incorporates carry-over value functions under limited foresight within a broader net work optimal water management model is developed. The approach uses annual carry-over value functions derived from small dimension stochastic dynamic programs embedded within a larger dimension water allocation network. The disaggregation of the carry-over value functions to the broader network is extended using the space rule concept. Initial results suggest that the solution of such annual nonlinear network optimizations is comparable to, or faster than, the solution of linear network problems over long time series.

  8. (Plant growth with limited water)

    SciTech Connect

    Not Available

    1991-01-01

    The work supported by DOE in the last year built on our earlier findings that stem growth in soybean subjected to limited water is inhibited first by a physical limitation followed in a few hours by metabolic changes that reduce the extensibility of the cell walls. With time, there is modest recovery in extensibility and a 28kD protein accumulates in the walls of the growth-affected cells. A 31kD protein that was 80% similar in amino acid sequence also was present but did not accumulate in the walls of the stem cells. Explorations of the mRNA for these proteins showed that the mRNA for the 28kD protein increased in the shoot in response to water deprivation but the mRNA for the 31kD protein did not accumulate. In contrast, the roots continued to grow and the mRNA for the 31kD protein accumulated but the mRNA for the 28kD protein was undetectable. We also explored how growth occurs in the absence of an external water supply. We found that, under these conditions, internal water is mobilized from surrounding nongrowing or slowly growing tissues and is used by rapidly growing cells. We showed that a low water potential is normally present in the enlarging tissues and is the likely force that extracts water from the surrounding tissues. We found that it involved a gradient in water potential that extended from the xylem to the outlying cells in the enlarging region and was not observed in the slowly growing basal tissue of the stems of the same plant. The gradient was measured directly with single cell determinations of turgor and osmotic potential in intact plants. The gradient may explain instances of growth inhibition with limited water when there is no change in the turgor of the enlarging cells. 17 refs.

  9. 50 CFR 622.496 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Annual catch limits (ACLs), annual catch.... Virgin Islands § 622.496 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). See § 622.12 for applicable ACLs and AMs....

  10. 50 CFR 622.457 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Annual catch limits (ACLs), annual catch.... Virgin Islands § 622.457 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). See § 622.12 for applicable ACLs and AMs....

  11. 50 CFR 622.439 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Annual catch limits (ACLs), annual catch.... Virgin Islands § 622.439 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). See § 622.12 for applicable ACLs and AMs....

  12. 50 CFR 622.439 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Annual catch limits (ACLs), annual catch.... Virgin Islands § 622.439 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). See § 622.12 for applicable ACLs and AMs....

  13. 50 CFR 622.58 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). 622.58 Section 622.58 Wildlife and Fisheries FISHERY... Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). (a) Royal...

  14. 50 CFR 622.251 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). 622.251 Section 622.251 Wildlife and Fisheries FISHERY... § 622.251 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs)....

  15. 50 CFR 622.193 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Annual catch limits (ACLs), annual catch... Region § 622.193 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures... commercial ACLs, in round weight, are 284,680 lb (129,129 kg) for 2012, 315,920 lb (143,299 kg) for 2013,...

  16. 50 CFR 622.251 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). 622.251 Section 622.251 Wildlife and Fisheries FISHERY... § 622.251 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs)....

  17. 50 CFR 622.457 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Annual catch limits (ACLs), annual catch.... Virgin Islands § 622.457 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). See § 622.12 for applicable ACLs and AMs....

  18. 50 CFR 622.41 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Annual catch limits (ACLs), annual catch....41 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). (a... sector for the remainder of that fishing year. (3) The stock complex ACLs for Other SWG, in gutted...

  19. 50 CFR 622.388 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). 622.388 Section 622.388 Wildlife and Fisheries FISHERY... Mexico and South Atlantic) § 622.388 Annual catch limits (ACLs), annual catch targets (ACTs),...

  20. 50 CFR 622.388 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). 622.388 Section 622.388 Wildlife and Fisheries FISHERY... Mexico and South Atlantic) § 622.388 Annual catch limits (ACLs), annual catch targets (ACTs),...

  1. 50 CFR 622.496 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Annual catch limits (ACLs), annual catch.... Virgin Islands § 622.496 Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). See § 622.12 for applicable ACLs and AMs....

  2. 50 CFR 622.58 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). 622.58 Section 622.58 Wildlife and Fisheries FISHERY... Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs). (a) Royal...

  3. New Stochastic Annual Limits on Intake for Selected Radionuclides

    SciTech Connect

    Carbaugh, Eugene H.

    2009-08-24

    Annual limits on intake (ALI) have historically been tabulated by the International Commission on Radiological Protection (e.g., ICRP 1979, 1961) and also by the Environmental Protection Agency (EPA 1988). These compilations have been rendered obsolete by more recent ICRP dosimetry methods, and, rather than provide new ALIs, the ICRP has opted instead to provide committed dose coefficients from which an ALI can be determined by a user for a specific set of conditions. The U.S. Department of Energy historically has referenced compilations of ALIs and has defined their method of calculation in its radiation protection regulation (10 CFDR 835), but has never provided a specific compilation. Under June 2007 amendments to 10 CFR 835, ALIs can be calculated by dividing an appropriate dose limit, either 5-rem (0.05 Sv) effective dose or 50 rem (0.5 Sv) equivalent dose to an individual organ or tissue, by an appropriate committed dose coefficient. When based on effective dose, the ALI is often referred to as a stochastic annual limit on intake (SALI), and when based on the individual organ or tissue equivalent limit, it has often been called a deterministic annual limit on intake (DALI).

  4. (Plant growth with limited water)

    SciTech Connect

    Not Available

    1992-01-01

    When water is in short supply, soybean stem growth is inhibited by a physical limitation followed in a few hours by metabolic changes that reduce the extensibility of the cell walls. The extensibility then becomes the main limitation. With time, there is a modest recovery in extensibility along with an accumulation of a 28kD protein in the walls of the growth-affected cells. A 3lkD protein that was 80% similar in amino acid sequence also was present but did not accumulate in the walls of the stem cells. In the stem, growth was inhibited and the mRNA for the 28kD protein increased in response to water deprivation but the mRNA for the 3 1 kD protein did not. The roots continued to grow and the mRNA for the 28kD protein did not accumulate but the mRNA for the 3lkD protein did. Thus, there was a tissuespecific response of gene expression that correlated with the contrasting growth response to low water potential in the same seedlings. Further work using immunogold labeling, fluorescence labeling, and western blotting gave evidence that the 28kD protein is located in the cell wall as well as several compartments in the cytoplasm. Preliminary experiments indicate that the 28kD protein is a phosphatase.

  5. 26 CFR 1.401(a)(17)-1 - Limitation on annual compensation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 5 2014-04-01 2014-04-01 false Limitation on annual compensation. 1.401(a)(17.... § 1.401(a)(17)-1 Limitation on annual compensation. (a) Compensation limit requirement—(1) In general... an annual compensation limit for each employee under a qualified plan. This limit applies to...

  6. 50 CFR 648.53 - Acceptable biological catch (ABC), annual catch limits (ACL), annual catch targets (ACT), DAS...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... catch limits (ACL), annual catch targets (ACT), DAS allocations, and individual fishing quotas (IFQ... limits (ACL), annual catch targets (ACT), DAS allocations, and individual fishing quotas (IFQ). (a... limited access scallop fishery shall be allocated 94.5 percent of the ACL specified in paragraph (a)(1)...

  7. Least limiting water range of soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The least limiting water range (LLWR) has been developed as an index of the soil structural quality. The LLWR was defined as the region bounded by the upper and lower soil water content over which water, oxygen, and mechanical resistance become major limitations for root growth. Thus, it combines th...

  8. 5 CFR 630.908 - Limitations on donation of annual leave.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Limitations on donation of annual leave... REGULATIONS ABSENCE AND LEAVE Voluntary Leave Transfer Program § 630.908 Limitations on donation of annual... amount of annual leave he or she would be entitled to accrue during the leave year in which the...

  9. Photosynthetic water splitting: 1987 annual report

    SciTech Connect

    Greenbaum, E.

    1988-01-01

    This document is an annual report of photosynthetic water splitting for the production of hydrogen and oxygen. Unicellular green algae are capable of evolving molecular hydrogen in the presence of carbon dioxide. Controlling factors that determine hydrogen evolution are either temperature or light intensity. Also, mutants of the green alga Chlamydomonas are capable of evolving hydrogen in the presence of carbon dioxide. The significance of these discoveries is that the presence of carbon dioxide (or bicarbonate) is a key factor in determining the activity of the Photosystem II water splitting complex. Second, a new advance in oxygen sensor technology has been made that, for the first time, allows the absolute measurement of photosynthetically evolved oxygen from a single colony of microalgae growing on a solidified agar medium. The key aspect of this electrochemical sensor is the utilization of ultra-pure potassium hydroxide as the electrolyte and a recognition of the role that electrolyte impurities play in contributing to base line noise. 9 refs., 8 figs., 2 tabs.

  10. 78 FR 48075 - Western Pacific Fisheries; 2013 Annual Catch Limits and Accountability Measures; Correcting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-07

    ... Catch Limits and Accountability Measures; Correcting Amendment AGENCY: National Marine Fisheries Service... limit specifications for western Pacific fisheries that were published in the Federal Register on March... Pacific Fishery Management Council (Council) recommended annual catch limits for western Pacific...

  11. Water limits to closing yield gaps

    NASA Astrophysics Data System (ADS)

    Davis, Kyle Frankel; Rulli, Maria Cristina; Garrassino, Francesco; Chiarelli, Davide; Seveso, Antonio; D'Odorico, Paolo

    2017-01-01

    Agricultural intensification is often seen as a suitable approach to meet the growing demand for agricultural products and improve food security. It typically entails the use of fertilizers, new cultivars, irrigation, and other modern technology. In regions of the world affected by seasonal or chronic water scarcity, yield gap closure is strongly dependent on irrigation (blue water). Global yield gap assessments have often ignored whether the water required to close the yield gap is locally available. Here we perform a gridded global analysis (10 km resolution) of the blue water consumption that is needed annually to close the yield gap worldwide and evaluate the associated pressure on renewable freshwater resources. We find that, to close the yield gap, human appropriation of freshwater resources for irrigation would have to increase at least by 146%. Most study countries would experience at least a doubling in blue water requirement, with 71% of the additional blue water being required by only four crops - maize, rice, soybeans, and wheat. Further, in some countries (e.g., Algeria, Morocco, Syria, Tunisia, and Yemen) the total volume of blue water required for yield gap closure would exceed sustainable levels of freshwater consumption (i.e., 40% of total renewable surface and groundwater resources).

  12. 39 CFR 3010.22 - Calculation of less than annual limitation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Calculation of less than annual limitation. 3010... MARKET DOMINANT PRODUCTS Rules for Applying the Price Cap § 3010.22 Calculation of less than annual limitation. (a) If a notice of rate adjustment is filed less than 1 year after the last Type 1-A or Type...

  13. 50 CFR 648.230 - Spiny dogfish Annual Catch Limits (ACLs).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Spiny dogfish Annual Catch Limits (ACLs... Management Measures for the Spiny Dogfish Fishery § 648.230 Spiny dogfish Annual Catch Limits (ACLs). (a) The... make recommendations to the Councils for changes in measures intended to ensure ACLs are not...

  14. 50 CFR 648.230 - Spiny dogfish Annual Catch Limits (ACLs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Spiny dogfish Annual Catch Limits (ACLs... Management Measures for the Spiny Dogfish Fishery § 648.230 Spiny dogfish Annual Catch Limits (ACLs). (a) The... make recommendations to the Councils for changes in measures intended to ensure ACLs are not...

  15. 50 CFR 648.230 - Spiny dogfish Annual Catch Limits (ACLs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Spiny dogfish Annual Catch Limits (ACLs... Management Measures for the Spiny Dogfish Fishery § 648.230 Spiny dogfish Annual Catch Limits (ACLs). (a) The... make recommendations to the Councils for changes in measures intended to ensure ACLs are not...

  16. 76 FR 8293 - Natural Gas Pipelines; Project Cost and Annual Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-14

    ... Energy Regulatory Commission 18 CFR Part 157 Natural Gas Pipelines; Project Cost and Annual Limits...) computes and publishes the project cost and annual limits for natural gas pipelines blanket construction... practice and procedure, Natural Gas, Reporting and recordkeeping requirements. Jeff C. Wright,...

  17. 78 FR 8389 - Natural Gas Pipelines; Project Cost and Annual Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ... Energy Regulatory Commission 18 CFR Part 157 Natural Gas Pipelines; Project Cost and Annual Limits AGENCY... publishes the project cost and annual limits for natural gas pipelines blanket construction certificates for... CFR Part 157 Administrative practice and procedure, Natural Gas, Reporting and...

  18. 77 FR 8724 - Natural Gas Pipelines; Project Cost and Annual Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... Energy Regulatory Commission 18 CFR Part 157 Natural Gas Pipelines; Project Cost and Annual Limits... (OEP) computes and publishes the project cost and annual limits for natural gas pipelines blanket..., Natural gas, Reporting and recordkeeping requirements. Jeff C. Wright, Director, Office of Energy...

  19. 75 FR 8245 - Natural Gas Pipelines; Project Cost and Annual Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ... Energy Regulatory Commission 18 CFR Part 157 Natural Gas Pipelines; Project Cost and Annual Limits...) computes and publishes the project cost and annual limits for natural gas pipelines blanket construction... Part 157 Administrative practice and procedure, Natural gas, Reporting and recordkeeping...

  20. 50 CFR 648.120 - Scup Annual Catch Limit (ACL).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... shall recommend to the MAFMC separate ACLs for the commercial and recreational scup fisheries, the sum... and recreational fishing sector ACLs will be established consistent with the allocation guidelines... recreational sector ACLs may be established on an annual basis for up to 3 years at a time, dependent...

  1. 50 CFR 648.290 - Tilefish Annual Catch Limit (ACL).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... detailed review of fishery performance relative to the sector ACLs at least every 5 years. (1) If the ACL... recommendations to the MAFMC for changes in measures intended to ensure ACLs are not as frequently exceeded. (2...) Performance reviews shall not substitute for annual reviews that occur to ascertain if prior year ACLs...

  2. 50 CFR 648.120 - Scup Annual Catch Limit (ACL).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... shall recommend to the MAFMC separate ACLs for the commercial and recreational scup fisheries, the sum... and recreational fishing sector ACLs will be established consistent with the allocation guidelines... recreational sector ACLs may be established on an annual basis for up to 3 years at a time, dependent...

  3. 50 CFR 648.290 - Tilefish Annual Catch Limit (ACL).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... detailed review of fishery performance relative to the sector ACLs at least every 5 years. (1) If the ACL... recommendations to the MAFMC for changes in measures intended to ensure ACLs are not as frequently exceeded. (2...) Performance reviews shall not substitute for annual reviews that occur to ascertain if prior year ACLs...

  4. 50 CFR 648.290 - Tilefish Annual Catch Limit (ACL).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... detailed review of fishery performance relative to the sector ACLs at least every 5 years. (1) If the ACL... recommendations to the MAFMC for changes in measures intended to ensure ACLs are not as frequently exceeded. (2...) Performance reviews shall not substitute for annual reviews that occur to ascertain if prior year ACLs...

  5. 50 CFR 648.120 - Scup Annual Catch Limit (ACL).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... shall recommend to the MAFMC separate ACLs for the commercial and recreational scup fisheries, the sum... and recreational fishing sector ACLs will be established consistent with the allocation guidelines... recreational sector ACLs may be established on an annual basis for up to 3 years at a time, dependent...

  6. Thermal-hydraulic limitations on water-cooled limiters

    SciTech Connect

    Cha, Y.S.; Misra, B.

    1984-08-01

    An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on current design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under asymmetrically heated conditions. Since the data presented herein concern primarily thermal protection, the final design should consider other factors such as thermal stresses, temperature limits, and fatigue.

  7. Efficiency limits for photoelectrochemical water-splitting

    PubMed Central

    Fountaine, Katherine T.; Lewerenz, Hans Joachim; Atwater, Harry A.

    2016-01-01

    Theoretical limiting efficiencies have a critical role in determining technological viability and expectations for device prototypes, as evidenced by the photovoltaics community's focus on detailed balance. However, due to their multicomponent nature, photoelectrochemical devices do not have an equivalent analogue to detailed balance, and reported theoretical efficiency limits vary depending on the assumptions made. Here we introduce a unified framework for photoelectrochemical device performance through which all previous limiting efficiencies can be understood and contextualized. Ideal and experimentally realistic limiting efficiencies are presented, and then generalized using five representative parameters—semiconductor absorption fraction, external radiative efficiency, series resistance, shunt resistance and catalytic exchange current density—to account for imperfect light absorption, charge transport and catalysis. Finally, we discuss the origin of deviations between the limits discussed herein and reported water-splitting efficiencies. This analysis provides insight into the primary factors that determine device performance and a powerful handle to improve device efficiency. PMID:27910847

  8. Efficiency limits for photoelectrochemical water-splitting

    NASA Astrophysics Data System (ADS)

    Fountaine, Katherine T.; Lewerenz, Hans Joachim; Atwater, Harry A.

    2016-12-01

    Theoretical limiting efficiencies have a critical role in determining technological viability and expectations for device prototypes, as evidenced by the photovoltaics community's focus on detailed balance. However, due to their multicomponent nature, photoelectrochemical devices do not have an equivalent analogue to detailed balance, and reported theoretical efficiency limits vary depending on the assumptions made. Here we introduce a unified framework for photoelectrochemical device performance through which all previous limiting efficiencies can be understood and contextualized. Ideal and experimentally realistic limiting efficiencies are presented, and then generalized using five representative parameters--semiconductor absorption fraction, external radiative efficiency, series resistance, shunt resistance and catalytic exchange current density--to account for imperfect light absorption, charge transport and catalysis. Finally, we discuss the origin of deviations between the limits discussed herein and reported water-splitting efficiencies. This analysis provides insight into the primary factors that determine device performance and a powerful handle to improve device efficiency.

  9. Water Budget, 1983-1985 Annual Report.

    SciTech Connect

    Maher, Mark

    1986-10-01

    This report encompasses the first three years (1983, 1984, and 1985) of operation. It includes: (1) background and history of the development of the Water Budget concept including a discussion of Water Budget manager positions; (2) implementation of the Water Budget since its formulation by the Council in 1983; (3) a discussion of the research and monitoring funded by BPA; and (4) a discussion of Section 304 of the Council's Program.

  10. Water Science and Technology Board Annual Report 2001-2002

    SciTech Connect

    2002-10-01

    This annual report marks the twentieth anniversary of the Water Science and Technology Board (WSTB) (1982-2002). The WSTB oversees studies of water issues. The principal products of studies are written reports. These reports cover a wide range of water resources issues of national concern. The following three recently issued reports illustrate the scope of the WSTB's studies: Envisioning the Agenda for Water Resources Research in the Twenty-first Century. The Missouri River Ecosystem: Exploring the Prospects for Recovery, and Assessing the TMDL Approach to Water Quality Management. The WSTB generally meets three times each year where discussions are held on ongoing projects, strategic planning, and developing new initiatives. The meetings also foster communication within the water resources community. The annual report includes a discussion on current studies, completed studies 2001-2002, and future plans, as well as a listing of published reports (1983-2002).

  11. 76 FR 53847 - New International Commission on Radiological Protection; Recommendations on the Annual Dose Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-30

    ... REIRS database (NUREG-0713, ``Occupational Radiation Exposure at Commercial Nuclear Power Reactors and... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY... Annual Dose Limit to the Lens of the Eye AGENCY: Nuclear Regulatory Commission. ACTION: Request...

  12. Ground Water Technical Support Center (GWTSC) Annual ...

    EPA Pesticide Factsheets

    The Ground Water Technical Support Center (GWTSC) is part of the Ground Water and Ecosystems Restoration Division (GWERD), which is based in the Robert S. Kerr Environmental Research Center in Ada, Oklahoma. The GWERD is a research division of U.S. EPA’s National Risk Management Research Laboratory (NRMRL). The GWTSC is one of an interlinked group of specialized Technical Support Centersthat were established under the Technical Support Project (TSP). The GWTSC provides technical support on issues related to groundwater. Specifically, the GWTSC provides technical support to U.S. EPA and State regulators for issues and problems related to:1. subsurface contamination (contaminants in ground water, soils and sediments),2. cross-media transfer (movement of contaminants from the subsurface to other media such as surface water or air), and3. restoration of impacted ecosystems.The GWTSC works with Remedial Project Managers (RPMs) and other decision makers to solve specific problems at Superfund, RCRA (Resource Conservation and Recovery Act), Brownfields sites, and ecosystem restoration sites. The Ground Water Technical Support Center (GWTSC) is part of the Ground Water and Ecosystems Restoration Division (GWERD), which is based in the Robert S. Kerr Environmental Research Center in Ada, Oklahoma. The GWERD is a research division of U.S. EPA’s National Risk Management Research Laboratory (NRMRL). The GWTSC is one of an interlinked group of specialized Technical Suppo

  13. 76 FR 10387 - Annual Indexing of Basic Statutory Mortgage Limits for Multifamily Housing Programs

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-24

    ... URBAN DEVELOPMENT Annual Indexing of Basic Statutory Mortgage Limits for Multifamily Housing Programs... Mortgage Limits for Multifamily Housing Programs for Calendar Year 2011. DATES: Effective Date: January 1... Dollar Amounts for Calendar Year 2011 are shown below: Basic Statutory Mortgage Limits for Calendar...

  14. Excess growing-season water limits lowland black spruce productivity

    NASA Astrophysics Data System (ADS)

    Dymond, S.; Kolka, R. K.; Bolstad, P. V.; Gill, K.; Curzon, M.; D'Amato, A. W.

    2015-12-01

    The annual growth of many tree species is limited by water availability, with growth increasing as water becomes less scarce. In lowland bogs of northern Minnesota, however, black spruce (Picea mariana) is often exposed to excess water via high water table elevations. These trees grow in thick deposits of organic mucky peat and often have shallow rooting systems to avoid the complete submersion of roots in water. While it is generally believed that black spruce decrease growth rates with rising water table elevations, this hypothesis has not been tested in situ. We used a unique, 50-year record of daily bog water table elevations at the Marcell Experimental Forest (MEF) in northern Minnesota to investigate the relationship between climate and black spruce productivity. Nine 1/20th ha circular plots were established in five different bogs and tree height, diameter-at-breast-height (DBH), and crown class were recorded. Additionally, two perpendicular cores were collected on all trees greater than 10 cm diameter-at-breast-height. Tree cores were sanded, mounted, cross-dated, and de-trended according to standard dendrochronological procedures. Ring width measurements were correlated with precipitation, temperature, and water table elevation using package BootRes in R to determine the climatic variables most associated with stand level productivity. Across the different plots, we found that early growing season water table elevation (May and June) was negatively correlated with both individual and stand-level black spruce growth (p < 0.01), while growth was positively correlated with March temperatures (p < 0.01). No significant relationships existed between black spruce growth and monthly precipitation. If summer water table elevations in these peatland ecosystems rise as is anticipated with more extreme precipitation events due to climate change, we could see an overall decrease in the stand level productivity of black spruce.

  15. The 16th James L. Waters Annual Symposium: Electrochemistry

    NASA Astrophysics Data System (ADS)

    Michael, Adrian C.

    2007-04-01

    The 16th Annual James L. Waters Symposium focused on electrochemistry, with emphasis on methods involving the flow of current. The speakers in this year's symposium are uniquely qualified to review the history of electroanalytical chemistry starting with Heyrovsky's initial studies and culminating with the present state of the art. Each has contributed significantly to the scientific, technical, and commercial development of the field.

  16. Mapping mean annual water yield and other hydrological variables for Alberta, Canada, 1971-2000

    NASA Astrophysics Data System (ADS)

    Mueller, M.; Kienzle, S. W.

    2011-12-01

    In Alberta, Canada, as in many other regions in the world, water is a limiting factor to population growth, economic development and environmental protection. The methods presented here were developed under a broader research project aimed to provide a water resources inventory for the province of Alberta. For 287 sub-watersheds, mean annual water yield, runoff coefficients, and actual evapotranspiration were computed from streamflow records and high resolution precipitation maps (PRISM) for the period 1971-2000. The analysis of the mean annual water yield is based on the association between the 287 gauged watershed areas and the respective streamflow production. Runoff coefficients were computed based on a spatial overlay of watershed boundaries and precipitation. Actual evapotranspiration was then computed by subtracting the mean annual water yield from the mean annual precipitation. Figure 1 shows a low resolution map example. The resulting maps are also available on the internet for 3 x 4' printouts and can be found by searching for "Alberta water yield". For 16 major watersheds in Alberta, the percent contribution of each sub-watershed is also listed.

  17. [Plant growth with limited water]. Performance report

    SciTech Connect

    Not Available

    1992-10-01

    When water is in short supply, soybean stem growth is inhibited by a physical limitation followed in a few hours by metabolic changes that reduce the extensibility of the cell walls. The extensibility then becomes the main limitation. With time, there is a modest recovery in extensibility along with an accumulation of a 28kD protein in the walls of the growth-affected cells. A 3lkD protein that was 80% similar in amino acid sequence also was present but did not accumulate in the walls of the stem cells. In the stem, growth was inhibited and the mRNA for the 28kD protein increased in response to water deprivation but the mRNA for the 3 1 kD protein did not. The roots continued to grow and the mRNA for the 28kD protein did not accumulate but the mRNA for the 3lkD protein did. Thus, there was a tissuespecific response of gene expression that correlated with the contrasting growth response to low water potential in the same seedlings. Further work using immunogold labeling, fluorescence labeling, and western blotting gave evidence that the 28kD protein is located in the cell wall as well as several compartments in the cytoplasm. Preliminary experiments indicate that the 28kD protein is a phosphatase.

  18. Water Science and Technology Board annual report 1988

    SciTech Connect

    Not Available

    1989-01-01

    This annual report of the Water Science and Technology Board (WSTB) summarizes the activities of the Board and its subgroups during 1988, its sixth year of existence. Included are descriptions of current and recently completed projects, new activities scheduled to begin in 1989, and plans for the future. The report also includes information on Board and committee memberships, program operational features, and reports produced during the past several years. This annual report is intended to provide an introduction to the WSTB and summary of its program for the year.

  19. Shift of annual water balance in the Budyko space for catchments with groundwater-dependent evapotranspiration

    NASA Astrophysics Data System (ADS)

    Wang, Xu-Sheng; Zhou, Yangxiao

    2016-09-01

    The Budyko framework represents the general relationship between the evapotranspiration ratio (F) and the aridity index (φ) for the mean annual steady-state water balance at the catchment scale. It is interesting to investigate whether this standard F - φ space can also be applied to capture the shift of annual water balance in catchments with varying dryness. Previous studies have made significant progress in incorporating the storage effect into the Budyko framework for the non-steady conditions, whereas the role of groundwater-dependent evapotranspiration was not investigated. This study investigates how groundwater-dependent evapotranspiration causes the shift of the annual water balance in the standard Budyko space. A widely used monthly hydrological model, the ABCD model, is modified to incorporate groundwater-dependent evapotranspiration into the zone with a shallow water table and delayed groundwater recharge into the zone with a deep water table. This model is applied in six catchments in the Erdos Plateau, China, to estimate the actual annual evapotranspiration. Results show that the variations in the annual F value with the aridity index do not satisfy the standard Budyko formulas. The shift of the annual water balance in the standard Budyko space is a combination of the Budyko-type response in the deep groundwater zone and the quasi-energy limited condition in the shallow groundwater zone. Excess evapotranspiration (F > 1) could occur in dry years, which is contributed by the significant supply of groundwater for evapotranspiration. Use of groundwater for irrigation can increase the frequency of the F > 1 cases.

  20. 29 CFR 2590.715-2711 - No lifetime or annual limits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... insurance coverage, may not establish any lifetime limit on the dollar amount of benefits for any individual... not establish any annual limit on the dollar amount of benefits for any individual. (ii) Exception for health flexible spending arrangements. A health flexible spending arrangement (as defined in section...

  1. 5 CFR 630.302 - Maximum annual leave accumulation-forty-five day limitation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-five day limitation. 630.302 Section 630.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT...—forty-five day limitation. (a) The effective date on which an employee (otherwise eligible thereunder... employee's accumulated and accrued annual leave is 30 days or less, he may carry forward the...

  2. 5 CFR 630.302 - Maximum annual leave accumulation-forty-five day limitation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...-five day limitation. 630.302 Section 630.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT...—forty-five day limitation. (a) The effective date on which an employee (otherwise eligible thereunder... employee's accumulated and accrued annual leave is 30 days or less, he may carry forward the...

  3. 5 CFR 630.302 - Maximum annual leave accumulation-forty-five day limitation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...-five day limitation. 630.302 Section 630.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT...—forty-five day limitation. (a) The effective date on which an employee (otherwise eligible thereunder... employee's accumulated and accrued annual leave is 30 days or less, he may carry forward the...

  4. 5 CFR 630.302 - Maximum annual leave accumulation-forty-five day limitation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...-five day limitation. 630.302 Section 630.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT...—forty-five day limitation. (a) The effective date on which an employee (otherwise eligible thereunder... employee's accumulated and accrued annual leave is 30 days or less, he may carry forward the...

  5. Water Science and Technology Board annual report 1989

    SciTech Connect

    Not Available

    1990-01-01

    This report summarizes the activities of the Water Science and Technology Board (WSTB) and its subgroups during 1989, it seventh year of existence. It describes current and recently completed projects, new activities scheduled to begin in 1990, and plans for the future. The report also includes information on Board and committee memberships, program operational features, and reports produced during the past several years. This annual report is an introduction to the WSTB and its program for the year. 4 figs.

  6. ANNUAL WATER BUDGETS FOR A FORESTED SINKHOLE WETLAND

    SciTech Connect

    Hill, Dr. Andrew Jason; Neary, Vincent S

    2012-01-01

    Annual water budgets spanning two years, 2004 and 2005, are constructed for a sinkhole wetland in the Tennessee Highland Rim following conversion of 13 % of its watershed to impervious surfaces. The effect of watershed development on the hydrology of the study wetland was significant. Surface runoff was the dominant input, with a contribution of 61.4 % of the total. An average of 18.9 % of gross precipitation was intercepted by the canopy and evaporated. Seepage from the surface water body to the local groundwater system accounted for 83.1 % of the total outflow. Deep recharge varied from 43.2 % (2004) to 12.1 % (2005) of total outflow. Overall, evapotranspiration accounted for 72.4 % of the total losses, with an average of 65.7 % lost from soil profile storage. The annual water budgets indicate that deep recharge is a significant hydrologic function performed by isolated sinkhole wetlands, or karst pans, on the Tennessee Highland Rim. Continued hydrologic monitoring of sinkhole wetlands are needed to evaluate hydrologic function and response to anthropogenic impacts. The regression technique developed to estimate surface runoff entering the wetland is shown to provide reasonable annual runoff estimates, but further testing is needed.

  7. 78 FR 23288 - Proposed Information Collection: State Water Resources Research Institute Program; Annual...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-18

    ... application for an allotment grant and provides an annual report on its activities under the grant. The State... submit the annual application; and 80 hours (total) per grantee to complete the annual reports. Annual... Geological Survey Proposed Information Collection: State Water Resources Research Institute Program;...

  8. 50 CFR 622.280 - Annual catch limits (ACLs) and accountability measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... MEXICO, AND SOUTH ATLANTIC Dolphin and Wahoo Fishery Off the Atlantic States § 622.280 Annual catch limits (ACLs) and accountability measures (AMs). (a) Atlantic dolphin—(1) Commercial sector. If commercial landings for Atlantic dolphin, as estimated by the SRD, reach or are projected to reach...

  9. 50 CFR 622.49 - Annual catch limits (ACLs) and accountability measures (AMs).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Annual catch limits (ACLs) and accountability measures (AMs). 622.49 Section 622.49 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE CARIBBEAN, GULF, AND SOUTH ATLANTIC Management Measures...

  10. 50 CFR 622.280 - Annual catch limits (ACLs) and accountability measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... MEXICO, AND SOUTH ATLANTIC Dolphin and Wahoo Fishery Off the Atlantic States § 622.280 Annual catch limits (ACLs) and accountability measures (AMs). (a) Atlantic dolphin—(1) Commercial sector. (i) If commercial landings for Atlantic dolphin, as estimated by the SRD, reach or are projected to reach...

  11. 75 FR 5800 - Annual Indexing of Basic Statutory Mortgage Limits for Multifamily Housing Programs

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-04

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT Annual Indexing of Basic Statutory Mortgage Limits for Multifamily Housing Programs AGENCY: Office of the Assistant Secretary for Housing--Federal Housing Commissioner, HUD. ACTION:...

  12. 12 CFR 1026.55 - Limitations on increasing annual percentage rates, fees, and charges.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 9 2014-01-01 2014-01-01 false Limitations on increasing annual percentage... disclosures required by paragraph (b)(1)(i) of this section are provided pursuant to § 1026.9(c), the card... to that category of transactions prior to provision of the notice; and (C) The card issuer must...

  13. 40 CFR Appendix A to Part 72 - Methodology for Annualization of Emissions Limits

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Methodology for Annualization of Emissions Limits A Appendix A to Part 72 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Pt. 72, App. A Appendix A to Part 72—Methodology...

  14. 40 CFR Appendix A to Part 72 - Methodology for Annualization of Emissions Limits

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Methodology for Annualization of Emissions Limits A Appendix A to Part 72 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Pt. 72, App. A Appendix A to Part 72—Methodology...

  15. Reduced pollinator service and elevated pollen limitation at the geographic range limit of an annual plant.

    PubMed

    Moeller, David A; Geber, Monica A; Eckhart, Vincent M; Tiffin, Peter

    2012-05-01

    Mutualisms are well known to influence individual fitness and the population dynamics of partner species, but little is known about whether they influence species distributions and the location of geographic range limits. Here, we examine the contribution of plant-pollinator interactions to the geographic range limit of the California endemic plant Clarkia xantiana ssp. xantiana. We show that pollinator availability declined from the center to the margin of the geographic range consistently across four years of study. This decline in pollinator availability was caused to a greater extent by variation in the abundance of generalist rather than specialist bee pollinators. Climate data suggest that patterns of precipitation in the current and previous year drove variation in bee abundance because of its effects on cues for bee emergence in the current year and the abundance of floral resources in the previous year. Experimental floral manipulations showed that marginal populations had greater outcross pollen limitation of reproduction, in parallel with the decline in pollinator abundance. Although plants are self-compatible, we found no evidence that autonomous selfing contributes to reproduction, and thus no evidence that it alleviates outcross pollen limitation in marginal populations. Furthermore, we found no association between the distance to the range edge and selfing rate, as estimated from sequence and microsatellite variation, indicating that the mating system has not evolved in response to the pollination environment at the range periphery. Overall, our results suggest that dependence on pollinators for reproduction may be an important constraint limiting range expansion in this system.

  16. 29 CFR 2520.104-44 - Limited exemption and alternative method of compliance for annual reporting by unfunded plans and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... annual reporting by unfunded plans and by certain insured plans. 2520.104-44 Section 2520.104-44 Labor... Limited exemption and alternative method of compliance for annual reporting by unfunded plans and by... this section is not required to comply with the annual reporting requirements described in paragraph...

  17. 78 FR 57378 - Proposed Information Collection Request; Comment Request; Annual Public Water System Compliance...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-18

    ... AGENCY Proposed Information Collection Request; Comment Request; Annual Public Water System Compliance... Protection Agency is planning to submit an information collection request (ICR), ``Annual Public Water System... available to the public, and submit to the Administrator of EPA, an annual report of violations of...

  18. Optimal root profiles in water-limited ecosystems

    NASA Astrophysics Data System (ADS)

    Rudd, Keith; Albertson, John D.; Ferrari, Silvia

    2014-09-01

    The vertical distribution of roots in the soil is of central importance to the mass and energy exchange between the land and the atmosphere. It has been demonstrated that the vertical root profiles which maximize transpiration in numerical experiments reflect well the characteristics of root profiles observed in nature for water-limited ecosystems. Previous research has demonstrated how the optimal vertical root profile depends on both the mean annual precipitation (MAP) and the soil texture. Recently, in the climate literature, it has been suggested Chou et al. (2012) [5] that increased greenhouse forcing in the tropics can lead to a simultaneous decrease in the frequency and increase in the intensity of precipitation. In this paper we demonstrate how such a change in the statistical structure of rainfall, even with no change to MAP, requires deeper root distributions to maintain optimal water use. These results raise interesting questions for future studies of nutrient dynamics, the cost of additional below ground carbon allocation, and inter plant functional type competition.

  19. Annual cycle and destruction of Eighteen Degree Water

    NASA Astrophysics Data System (ADS)

    Billheimer, Sam; Talley, Lynne D.

    2016-09-01

    Eighteen Degree Water (EDW), the subtropical mode water of the western North Atlantic, is a voluminous, weakly stratified upper ocean water mass that acts as a subsurface reservoir of heat, nutrients, and CO2. This thick layer persists throughout the year, but nearly half of its volume is dispersed or mixed away, diffusing its properties into the thermocline, from the time it outcrops in winter until it is renewed the following year. CTD observations from Argo profiling floats and acoustically tracked, isothermally bound profiling floats are used to quantify EDW destruction rates and investigate the relevant processes responsible for the large annual cycle of EDW. EDW destruction occurs primarily at the top of the EDW layer, with the highest EDW destruction rates occurring during early summer. Slower, steadier EDW destruction is observed in early winter. EDW destruction is dominated by 1-D vertical diffusion, while mesoscale, along-isopycnal stirring is also significant, explaining approximately 1/3 of the total annual EDW destruction. Destruction via along-isopycnal processes is more prevalent near the Gulf Stream than in the southern Sargasso Sea, due to higher potential vorticity gradients and enhanced mesoscale activity.

  20. Water Science and Technology Board annual report 1987

    SciTech Connect

    Not Available

    1988-01-01

    In 1982, the National Research Council chose to recognize the importance of water resource issues by establishing the Water Science and Technology Board (WSTB). During the five years since its first meeting in November 1982, the WSTB has grown and matured. The WSTB has met 14 times to provide guidance and plan activities. Under the WSTB's direction, committees of experts have conducted approximately 30 studies on a broad array of topics, from dam safety to irrigation-induced water quality problems to ground water protection strategies. Studies have ranged in scope from the oversight of specific agency projects and programs to broader scientific reviews, such as a disciplinary assessment of the hydrologic sciences initiated in 1987. In all cases, studies have the general theme of ultimately improving the scientific and technological bases of programs of water management and environmental quality. This fifth annual report of the WSTB summarizes the Board's accomplishments during 1987, its current activities, and its plans for the future. The report also includes information on Board and committee memberships, program organizations, and the reports produced. The report should provide the reader with a basic understanding of the WSTB's interests, achievements, and capabilities. The WSTB welcomes inquiries and suggestions concerning its activities and will provide more detailed information on any aspects of its work to those interested.

  1. Limiting invasive species in ballast water

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2011-06-01

    Ballast water is often intentionally loaded onto cargo ships and other vessels to provide weight necessary for safe maneuvering. However, this practice can unintentionally transport exotic organisms to parts of the world where populations of these organisms can establish themselves in new habitats as invasive and environmentally and economically disruptive species. Each year, an estimated 196 million metric tons of ballast water are discharged into U.S. coastal waters and the Great Lakes alone from an average of more than 90,000 visits of commercial ships greater than 300 metric tons, according to a 2 June report by the U.S. National Research Council (NRC) of the National Academies.

  2. Bioenergy Sorghum Crop Model Predicts VPD-Limited Transpiration Traits Enhance Biomass Yield in Water-Limited Environments

    PubMed Central

    Truong, Sandra K.; McCormick, Ryan F.; Mullet, John E.

    2017-01-01

    Bioenergy sorghum is targeted for production in water-limited annual cropland therefore traits that improve plant water capture, water use efficiency, and resilience to water deficit are necessary to maximize productivity. A crop modeling framework, APSIM, was adapted to predict the growth and biomass yield of energy sorghum and to identify potentially useful traits for crop improvement. APSIM simulations of energy sorghum development and biomass accumulation replicated results from field experiments across multiple years, patterns of rainfall, and irrigation schemes. Modeling showed that energy sorghum's long duration of vegetative growth increased water capture and biomass yield by ~30% compared to short season crops in a water-limited production region. Additionally, APSIM was extended to enable modeling of VPD-limited transpiration traits that reduce crop water use under high vapor pressure deficits (VPDs). The response of transpiration rate to increasing VPD was modeled as a linear response until a VPD threshold was reached, at which the slope of the response decreases, representing a range of responses to VPD observed in sorghum germplasm. Simulation results indicated that the VPD-limited transpiration trait is most beneficial in hot and dry regions of production where crops are exposed to extended periods without rainfall during the season or to a terminal drought. In these environments, slower but more efficient transpiration increases biomass yield and prevents or delays the exhaustion of soil water and onset of leaf senescence. The VPD-limited transpiration responses observed in sorghum germplasm increased biomass accumulation by 20% in years with lower summer rainfall, and the ability to drastically reduce transpiration under high VPD conditions could increase biomass by 6% on average across all years. This work indicates that the productivity and resilience of bioenergy sorghum grown in water-limited environments could be further enhanced by development

  3. Bioenergy Sorghum Crop Model Predicts VPD-Limited Transpiration Traits Enhance Biomass Yield in Water-Limited Environments.

    PubMed

    Truong, Sandra K; McCormick, Ryan F; Mullet, John E

    2017-01-01

    Bioenergy sorghum is targeted for production in water-limited annual cropland therefore traits that improve plant water capture, water use efficiency, and resilience to water deficit are necessary to maximize productivity. A crop modeling framework, APSIM, was adapted to predict the growth and biomass yield of energy sorghum and to identify potentially useful traits for crop improvement. APSIM simulations of energy sorghum development and biomass accumulation replicated results from field experiments across multiple years, patterns of rainfall, and irrigation schemes. Modeling showed that energy sorghum's long duration of vegetative growth increased water capture and biomass yield by ~30% compared to short season crops in a water-limited production region. Additionally, APSIM was extended to enable modeling of VPD-limited transpiration traits that reduce crop water use under high vapor pressure deficits (VPDs). The response of transpiration rate to increasing VPD was modeled as a linear response until a VPD threshold was reached, at which the slope of the response decreases, representing a range of responses to VPD observed in sorghum germplasm. Simulation results indicated that the VPD-limited transpiration trait is most beneficial in hot and dry regions of production where crops are exposed to extended periods without rainfall during the season or to a terminal drought. In these environments, slower but more efficient transpiration increases biomass yield and prevents or delays the exhaustion of soil water and onset of leaf senescence. The VPD-limited transpiration responses observed in sorghum germplasm increased biomass accumulation by 20% in years with lower summer rainfall, and the ability to drastically reduce transpiration under high VPD conditions could increase biomass by 6% on average across all years. This work indicates that the productivity and resilience of bioenergy sorghum grown in water-limited environments could be further enhanced by development

  4. Water chemistry, seepage investigation, streamflow, reservoir storage, and annual availability of water for the San Juan-Chama Project, northern New Mexico, 1942-2010

    USGS Publications Warehouse

    McKean, Sarah E.; Anderholm, Scott K.

    2014-01-01

    at Azotea Tunnel Outlet occurred from May through June, with a median duration of slightly longer than a month. Years with higher maximum daily streamflow generally are associated with higher annual streamflow than years with lower maximum daily streamflow. The amount of water that can be diverted for the SJCP is controlled by the availability of streamflow and is limited by several factors including legal limits for diversion, limits from the SJCP infrastructure including the size of the diversion dams and tunnels, the capacity of Heron Reservoir, and operational constraints that limit when water can be diverted. The average annual streamflow at Azotea Tunnel Outlet was 94,710 acre-feet, and the annual streamflow at Azotea Tunnel Outlet was approximately 75 percent of the annual streamflow available for the SJCP. The average annual percentage of available streamflow not diverted for the SJCP was 14 percent because of structural limitations of the capacity of infrastructure, 1 percent because of limitations of the reservoir storage capacity, and 29 percent because of the limitations from operations. For most years, the annual available streamflow not diverted for unknown reasons exceeded the sum of the water not diverted because of structural, capacity, and operational limitations.

  5. On the use of a water balance to evaluate inter-annual terrestrial ET variability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurately measuring inter-annual variability in terrestrial evapotranspiration (ET) is a major challenge for efforts to detect inter-annual variability in the hydrologic cycle. Based on comparisons with annual ET values derived from a terrestrial water balance analysis, past research has cast doubt...

  6. Contrasting precipitation seasonality influences evapotranspiration dynamics in water-limited shrublands

    NASA Astrophysics Data System (ADS)

    Villarreal, Samuel; Vargas, Rodrigo; Yepez, Enrico A.; Acosta, Jose S.; Castro, Angel; Escoto-Rodriguez, Martin; Lopez, Eulogio; Martínez-Osuna, Juan; Rodriguez, Julio C.; Smith, Stephen V.; Vivoni, Enrique R.; Watts, Christopher J.

    2016-02-01

    Water-limited ecosystems occupy nearly 30% of the Earth, but arguably, the controls on their ecosystem processes remain largely uncertain. We analyzed six site years of eddy covariance measurements of evapotranspiration (ET) from 2008 to 2010 at two water-limited shrublands: one dominated by winter precipitation (WP site) and another dominated by summer precipitation (SP site), but with similar solar radiation patterns in the Northern Hemisphere. We determined how physical forcing factors (i.e., net radiation (Rn), soil water content (SWC), air temperature (Ta), and vapor pressure deficit (VPD)) influence annual and seasonal variability of ET. Mean annual ET at SP site was 455 ± 91 mm yr-1, was mainly influenced by SWC during the dry season, by Rn during the wet season, and was highly sensitive to changes in annual precipitation (P). Mean annual ET at WP site was 363 ± 52 mm yr-1, had less interannual variability, but multiple variables (i.e., SWC, Ta, VPD, and Rn) were needed to explain ET among years and seasons. Wavelet coherence analysis showed that ET at SP site has a consistent temporal coherency with Ta and P, but this was not the case for ET at WP site. Our results support the paradigm that SWC is the main control of ET in water-limited ecosystems when radiation and temperature are not the limiting factors. In contrast, when P and SWC are decoupled from available energy (i.e., radiation and temperature), then ET is controlled by an interaction of multiple variables. Our results bring attention to the need for better understanding how climate and soil dynamics influence ET across these globally distributed ecosystems.

  7. Limited irrigation research and infrared thermometry for detecting water stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA-ARS Limited Irrigation Research Farm, located outside of Greeley Colorado, is an experiment evaluating management perspectives of limited irrigation water. An overview of the farm systems is shown, including drip irrigation systems, water budgeting, and experimental design, as well as preli...

  8. 78 FR 62331 - Fisheries of the Northeastern United States; Atlantic Herring Fishery; Sub-Annual Catch Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-17

    ... Northeastern United States; Atlantic Herring Fishery; Sub-Annual Catch Limit (ACL) Harvested for Management...), optimum yield, domestic harvest and processing, U.S. at-sea processing, border transfer, and sub-ACLs for each management area. The 2013 Domestic Annual Harvest is 107,800 metric tons (mt); the 2013...

  9. 78 FR 63406 - Fisheries of the Northeastern United States; Atlantic Herring Fishery; Sub-Annual Catch Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... Northeastern United States; Atlantic Herring Fishery; Sub-Annual Catch Limit (ACL) Harvested for Management..., and sub-ACLs for each management area. The 2013 Domestic Annual Harvest is 107,800 metric tons (mt); the 2013 sub-ACL allocated to Area 3 is 42,000 mt, and 0 mt of the sub-ACL is set aside for...

  10. The dynamic of annual carbon allocation to wood in European forests is consistent with a combined source-sink limitation of growth: implications for modelling

    NASA Astrophysics Data System (ADS)

    Guillemot, J.; Martin-StPaul, N. K.; Dufrêne, E.; François, C.; Soudani, K.; Ourcival, J. M.; Delpierre, N.

    2015-02-01

    The extent to which forest growth is limited by carbon (C) supply (source control) or by cambial activity (sink control) will condition the response of trees to global changes. However, the physiological processes responsible for the limitation of forest growth are still under debate. The aim of this study is to evaluate the key drivers of the annual carbon allocation to wood along large soil and climate regional gradients in five tree species representative of the main European forest biomes (Fagus sylvatica, Quercus petraea, Quercus ilex, Quercus robur and Picea abies). Combining field measurements and process-based simulations at 49 sites (931 site-years), we assessed the stand biomass growth dependences at both inter-site and inter-annual scales. Specifically, the relative influence of forest C balance (source control), direct environmental control (water and temperature controls of sink activity) and allocation adjustments related to age, past climate conditions, competition intensity and soil nutrient availability on growth were quantified. The inter-site variability in stand C allocation to wood was predominantly driven by an age-related decline. The direct control of temperature or water stress on sink activity (i.e. independently from their effects on C supply) exerted a strong influence on the annual stand woody growth in all the species considered, including deciduous temperate species. The lagged effect of the past environment conditions was a significant driver of the annual C allocation to wood. Carbon supply appeared to strongly limit growth only in deciduous temperate species. We provide an evaluation of the spatio-temporal dynamics of annual carbon allocation to wood in European forests. Our study supports the premise that European forest growth is under a complex control including both source and sink limitations. The relative influences of the different growth drivers strongly vary across years and spatial ecological gradients. We suggest a

  11. The dynamic of the annual carbon allocation to wood in European tree species is consistent with a combined source-sink limitation of growth: implications for modelling

    NASA Astrophysics Data System (ADS)

    Guillemot, J.; Martin-StPaul, N. K.; Dufrene, E.; Francois, C.; Soudani, K.; Ourcival, J. M.; Delpierre, N.

    2015-05-01

    The extent to which wood growth is limited by carbon (C) supply (i.e. source control) or by cambial activity (i.e. sink control) will strongly determine the responses of trees to global changes. Nevertheless, the physiological processes that are responsible for limiting forest growth are still a matter of debate. The aim of this study was to evaluate the key determinants of the annual C allocation to wood along large soil and climate regional gradients over France. The study was conducted for five tree species representative of the main European forest biomes (Fagus sylvatica, Quercus petraea, Quercus ilex, Quercus robur and Picea abies). The drivers of stand biomass growth were assessed on both inter-site and inter-annual scales. Our data set comprised field measurements performed at 49 sites (931 site-years) that included biometric measurements and a variety of stand characteristics (e.g. soil water holding capacity, leaf area index). It was complemented with process-based simulations when possible explanatory variables could not be directly measured (e.g. annual and seasonal tree C balance, bioclimatic water stress indices). Specifically, the relative influences of tree C balance (source control), direct environmental control (water and temperature controls of sink activity) and allocation adjustments related to age, past climate conditions, competition intensity and soil nutrient availability on growth were quantified. The inter-site variability in the stand C allocation to wood was predominantly driven by age-related decline. The direct effects of temperature and water stress on sink activity (i.e. effects independent from their effects on the C supply) exerted a strong influence on the annual stand wood growth in all of the species considered, including deciduous temperate species. The lagged effect of the past environmental conditions (e.g. the previous year's water stress and low C uptake) significantly affected the annual C allocation to wood. The C supply

  12. Options for complying with water quality-based metal limitations

    SciTech Connect

    Thibodeau, J.

    1996-12-31

    During the past six years, most states have promulgated water quality regulations which contain numerical aquatic life standards for heavy metals. In addition, the Environmental Protection Agency (EPA) promulgated national water quality standards in 1992 which also include numerical aquatic life criteria for heavy metals. Numerous wastewater discharge permits have been issued by the states and EPA to industrial facilities which include low microgram per liter heavy metal limitations. In many instances, the limitations are below detection limits or treatability limits using state-of-the-art analytical methods or treatment technologies. This paper will discuss options for conducting studies, including the use of water-effect ratios, metal partitioning coefficients, and recalculation procedures to develop site-specific metals criteria and higher permit limitations. The installation of expensive metal treatment systems to remove trace metals may be avoided if higher permit limits are indicated by the site-specific studies. 11 refs.

  13. Peak water limits to freshwater withdrawal and use.

    PubMed

    Gleick, Peter H; Palaniappan, Meena

    2010-06-22

    Freshwater resources are fundamental for maintaining human health, agricultural production, economic activity as well as critical ecosystem functions. As populations and economies grow, new constraints on water resources are appearing, raising questions about limits to water availability. Such resource questions are not new. The specter of "peak oil"--a peaking and then decline in oil production--has long been predicted and debated. We present here a detailed assessment and definition of three concepts of "peak water": peak renewable water, peak nonrenewable water, and peak ecological water. These concepts can help hydrologists, water managers, policy makers, and the public understand and manage different water systems more effectively and sustainably. Peak renewable water applies where flow constraints limit total water availability over time. Peak nonrenewable water is observable in groundwater systems where production rates substantially exceed natural recharge rates and where overpumping or contamination leads to a peak of production followed by a decline, similar to more traditional peak-oil curves. Peak "ecological" water is defined as the point beyond which the total costs of ecological disruptions and damages exceed the total value provided by human use of that water. Despite uncertainties in quantifying many of these costs and benefits in consistent ways, more and more watersheds appear to have already passed the point of peak water. Applying these concepts can help shift the way freshwater resources are managed toward more productive, equitable, efficient, and sustainable use.

  14. Peak water limits to freshwater withdrawal and use

    PubMed Central

    Gleick, Peter H.; Palaniappan, Meena

    2010-01-01

    Freshwater resources are fundamental for maintaining human health, agricultural production, economic activity as well as critical ecosystem functions. As populations and economies grow, new constraints on water resources are appearing, raising questions about limits to water availability. Such resource questions are not new. The specter of “peak oil”—a peaking and then decline in oil production—has long been predicted and debated. We present here a detailed assessment and definition of three concepts of “peak water”: peak renewable water, peak nonrenewable water, and peak ecological water. These concepts can help hydrologists, water managers, policy makers, and the public understand and manage different water systems more effectively and sustainably. Peak renewable water applies where flow constraints limit total water availability over time. Peak nonrenewable water is observable in groundwater systems where production rates substantially exceed natural recharge rates and where overpumping or contamination leads to a peak of production followed by a decline, similar to more traditional peak-oil curves. Peak “ecological” water is defined as the point beyond which the total costs of ecological disruptions and damages exceed the total value provided by human use of that water. Despite uncertainties in quantifying many of these costs and benefits in consistent ways, more and more watersheds appear to have already passed the point of peak water. Applying these concepts can help shift the way freshwater resources are managed toward more productive, equitable, efficient, and sustainable use. PMID:20498082

  15. Links Between Flood Frequency and Annual Water Balance Behaviors: A Basis for Similarity and Regionalization

    SciTech Connect

    Guo, Jiali; Li, Hongyi; Leung, Lai-Yung R.; Guo, Shenglian; Liu, Pan; Sivapalan, Murugesu

    2014-03-28

    This paper presents the results of a data based comparative study of several hundred catchments across continental United States belonging to the MOPEX dataset, which systematically explored the connection between the flood frequency curve and measures of mean annual water balance. Two different measures of mean annual water balance are used: (i) a climatic aridity index, AI, which is a measure of the competition between water and energy availability at the annual scale; and, (ii) baseflow index, BFI, the ratio of slow runoff to total runoff also at the annual time scale, reflecting the role of geology, soils, topography and vegetation. The data analyses showed that the aridity index, AI, has a first order control on both the mean and Cv of annual maximum floods. While mean annual flood decreases with increasing aridity, Cv increases with increasing aridity. BFI appeared to be a second order control on the magnitude and shape of the flood frequency curve. Higher BFI, meaning more subsurface flow and less surface flow leads to a decrease of mean annual flood whereas lower BFI leads to accumulation of soil moisture and increased flood magnitudes that arise from many events acting together. The results presented in this paper provide innovative means to delineate homogeneous regions within which the flood frequency curves can be assumed to be functionally similar. At another level, understanding the connection between annual water balance and flood frequency will be another building block towards developing comprehensive understanding of catchment runoff behavior in a holistic way.

  16. 50 CFR 648.53 - Acceptable biological catch (ABC), annual catch limits (ACL), annual catch targets (ACT), DAS...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... divided as sub-ACLs between limited access vessels, limited access vessels that are fishing under a LAGC... adjustment. (i) The limited access fishery sub-ACLs for fishing years 2014 and 2015 are: (A) 2014: 18,885 mt...). (i) The ACLs for fishing years 2014 and 2015 for LAGC IFQ vessels without a limited access...

  17. 50 CFR 648.53 - Acceptable biological catch (ABC), annual catch limits (ACL), annual catch targets (ACT), DAS...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... divided as sub-ACLs between limited access vessels, limited access vessels that are fishing under a LAGC... adjustment. (i) The limited access fishery sub-ACLs for fishing years 2013 and 2014 are: (A) 2013: 19,093 mt... paragraph (a). (i) The ACLs for fishing years 2013 and 2014 for LAGC IFQ vessels without a limited...

  18. Effects of rainfall seasonality and soil moisture capacity on mean annual water balance for Australian catchments

    USGS Publications Warehouse

    Potter, N.J.; Zhang, L.; Milly, P.C.D.; McMahon, T.A.; Jakeman, A.J.

    2005-01-01

    An important factor controlling catchment-scale water balance is the seasonal variation of climate. The aim of this study is to investigate the effect of the seasonal distributions of water and energy, and their interactions with the soil moisture store, on mean annual water balance in Australia at catchment scales using a stochastic model of soil moisture balance with seasonally varying forcing. The rainfall regime at 262 catchments around Australia was modeled as a Poisson process with the mean storm arrival rate and the mean storm depth varying throughout the year as cosine curves with annual periods. The soil moisture dynamics were represented by use of a single, finite water store having infinite infiltration capacity, and the potential evapotranspiration rate was modeled as an annual cosine curve. The mean annual water budget was calculated numerically using a Monte Carlo simulation. The model predicted that for a given level of climatic aridity the ratio of mean annual evapotranspiration to rainfall was larger where the potential evapotranspiration and rainfall were in phase, that is, in summer-dominant rainfall catchments, than where they were out of phase. The observed mean annual evapotranspiration ratios have opposite results. As a result, estimates of mean annual evapotranspiration from the model compared poorly with observational data. Because the inclusion of seasonally varying forcing alone was not sufficient to explain variability in the mean annual water balance, other catchment properties may play a role. Further analysis showed that the water balance was highly sensitive to the catchment-scale soil moisture capacity. Calibrations of this parameter indicated that infiltration-excess runoff might be an important process, especially for the summer-dominant rainfall catchments; most similar studies have shown that modeling of infiltration-excess runoff is not required at the mean annual timescale. Copyright 2005 by the American Geophysical Union.

  19. Limits of state activity in the interstate water market

    SciTech Connect

    Rodgers, A.B.

    1986-01-01

    In an effort to ensure future water supplies, many western states are becoming participants in the market for water. As market participants, states gain a proprietary interest in their water resources which more effectively secures their right to the water than mere regulation or claims of ownership under the public trust doctrine. As the author points out, however, the constitution imposes numerous limitations on state water market activity. The privileges and immunities clause, the commerce clause, the property clause, as well as the equal protection clause of the fourteenth amendment, all influence the manner in which states may behave. Most significantly, the author explains, these clauses prevent states from using their power as water market participants as a disguise for economic protectionism.

  20. 50 CFR 648.53 - Acceptable biological catch (ABC), annual catch limits (ACL), annual catch targets (ACT), DAS...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... divided as sub-ACLs between limited access vessels, limited access vessels that are fishing under a... limited access fishery sub-ACLs for fishing years 2011 through 2013 are: (A) 2011: 24,954 mt. (B) 2012: 26... catch, observer set-aside, and research set-aside, as specified in this paragraph (a). The LAGC ACLs...

  1. Assessment of Crop Water Requirement Methods for Annual Agricultural Water Allocation Planning

    NASA Astrophysics Data System (ADS)

    Aghdasi, F.; Sharifi, M. A.; van der Tol, C.

    2010-05-01

    The potential use of remote sensing in water resource and in particular in irrigation management has been widely acknowledged. However, in reality, operational applications of remote sensing in irrigation management are few. In this study, the applicability of the main available remote sensing based techniques of irrigation management is evaluated in a pilot area in Iran. The evaluated techniques include so called Crop Water Requirement "CWR" methods for the planning of annual water allocation in irrigated agriculture. A total of 40 years of historical weather data were classified into wet, normal, and dry years using a Standardised Precipitation Index (SPI). For each of these three classes the average CWR was calculated. Next, by applying Markov Chain Process to the time series of precipitation, the expected CWR for the forthcoming planning year was estimated. Using proper interpolation techniques the expected CWR at each station was converted to CWR map of the area, which was then used for annual water allocation planning. To estimate the crop water requirement, methods developed for the DEMETER project (DEMonstration of Earth observation Technologies in Routine irrigation advisory services) and Surface Energy Balance System "SEBS" algorithm were used, and their results were compared with conventional methods, including FAO-56 and lysimeter data amongst others. Use was made of both ASTER and MODIS images to determine crop water requirement at local and regional scales. Four methods of estimating crop coefficients were used: DEMETER Kc-NDVI, DEMETER Kc-analytical, FAO-56 and SEBS algorithm. Results showed that DEMETER (analytical approach) and FAO methods with lowest RMSE are more suitable methods for determination of crop coefficient than SEBS, which gives actual rather than potential evapotranspiration. The use of ASTER and MODIS images did not result in significantly different crop coefficients in the pilot area for the DEMETER analytical approach (α=0

  2. Constraining Annual Water Balance Estimates with Basin-Scale Observations from the Airborne Snow Observatory during the Current Californian Drought

    NASA Astrophysics Data System (ADS)

    Bormann, K.; Painter, T. H.; Marks, D. G.; Hedrick, A. R.; Deems, J. S.; Patterson, V.; McGurk, B. J.

    2015-12-01

    One of the great unknowns in mountain hydrology is how much water is stored within a seasonal snowpack at the basin scale. Quantifying mountain water resources is critical for assisting with water resource management, but has proven elusive due to high spatial and temporal variability of mountain snow cover, complex terrain, accessibility constraints and limited in-situ networks. The Airborne Snow Observatory (ASO, aso.jpl.nasa.gov) uses coupled airborne LiDAR and spectrometer instruments for high resolution snow depth retrievals which are used to derive unprecedented basin-wide estimates of snow water mass (snow water equivalent, SWE). ASO has been operational over key basins in the Sierra Nevada Mountains in California since 2013. Each operational year has been very dry, with precipitation in 2013 at 75% of average, 2014 at 50% of average and 2015 - the lowest snow year on record for the region. With vastly improved estimates of the snowpack water content from ASO, we can now for the first time conduct observation-based mass balance accounting of surface water in snow-dominated basins, and reconcile these estimates with observed reservoir inflows. In this study we use ASO SWE data to constrain mass balance accounting of basin annual water storages to quantify the water contained within the snowpack above the Hetch Hetchy water supply reservoir (Tuolumne River basin, California). The analysis compares and contrasts annual snow water volumes from observed reservoir inflows, snow water volume estimates from ASO, a physically based model that simulates the snowpack from meteorological inputs and a semi-distributed hydrological model. The study provides invaluable insight to the overall volume of water contained within a seasonal snowpack during a severe drought and how these quantities are simulated in our modelling systems. We envisage that this research will be of great interest to snowpack modellers, hydrologists, dam operators and water managers worldwide.

  3. DOE Annual Progress Report: Water Needs and Constraints for Hydrogen Pathways

    SciTech Connect

    Simon, A; Daily, W

    2009-07-02

    Water is a critical feedstock in the production of hydrogen. In fact, water and many of the energy transformations upon which society depends are inextricably linked. Approximately 39% of freshwater withdrawals are used for cooling of power plants, and another 8% are used in industry and mining (including oil and gas extraction and refining). Major changes in the energy infrastructure (as envisioned in a transformation to a hydrogen economy) will necessarily result in changes to the water infrastructure. Depending on the manner in which a hydrogen economy evolves, these changes could be large or small, detrimental or benign. Water is used as a chemical feedstock for hydrogen production and as a coolant for the production process. Process and cooling water must meet minimum quality specifications (limits on mineral and organic contaminants) at both the inlet to the process and at the point of discharge. If these specifications are not met, then the water must be treated, which involves extra expenditure on equipment and energy. There are multiple options for water treatment and cooling systems, each of which has a different profile of equipment cost and operational requirements. The engineering decisions that are made when building out the hydrogen infrastructure will play an important role in the cost of producing hydrogen, and those decisions will be influenced by the regional and national policies that help to manage water resources. In order to evaluate the impacts of water on hydrogen production and of a hydrogen economy on water resources, this project takes a narrowly-scoped lifecycle analysis approach. We begin with a process model of hydrogen production and calculate the process water, cooling, electricity and energy feedstock demands. We expand beyond the production process itself by analyzing the details of the cooling system and water treatment system. At a regional scale, we also consider the water use associated with the electricity and fuel that feed

  4. Extreme rainfall events can alter inter-annual biomass responses to water and N enrichment

    NASA Astrophysics Data System (ADS)

    Kong, D. L.; Lü, X. T.; Jiang, L. L.; Wu, H. F.; Miao, Y.; Kardol, P.

    2013-12-01

    Water availability has profound effects on plant growth and productivity in temperate and semiarid grasslands. However, it remains unclear how variation of inter-annual precipitation by extreme rainfall events will alter the aboveground and belowground responses of plants, and how these responses may be contingent on N availability. In this study, we examined the interactive effects of inter-annual precipitation variation and N addition on aboveground and live fine root biomass of a semiarid grassland in northern China for two consecutive years (2007 and 2008). Inter-annual variation in precipitation resulting mainly from the occurrence of extreme rainfall events in 2008 significantly affected above- and belowground plant biomass responses to water addition. In addition, variation of inter-annual precipitation by this extreme rainfall event suppressed plant responses to nitrogen addition and reduced the interaction effects between water and nitrogen addition. These effects of inter-annual precipitation fluctuation could be attributed to the negative influence of the extreme rainfall event on soil N and water availability, ultimately reducing plant rainfall use efficiency and nitrogen use efficiency. In conclusion, our results suggest ecosystem responses to water and N enrichment could be altered by inter-annual variation of precipitation regime caused by the naturally occurring extreme rainfall events.

  5. Alfalfa response to irrigation from limited water supplies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A five-year field study (2007-2011) of irrigated alfalfa production with a limited water supply was conducted in southwest Kansas with two years of above-average precipitation, one year of average precipitation, and two years of below-average precipitation. The irrigation treatments were designed to...

  6. Annual estimates of water and solute export from 42 tributaries to the Yukon River

    USGS Publications Warehouse

    Frederick Zanden,; Suzanne P. Anderson,; Striegl, Robert G.

    2012-01-01

    Annual export of 11 major and trace solutes for the Yukon River is found to be accurately determined based on summing 42 tributary contributions. These findings provide the first published estimates of tributary specific distribution of solutes within the Yukon River basin. First, we show that annual discharge of the Yukon River can be computed by summing calculated annual discharges from 42 tributaries. Annual discharge for the tributaries is calculated from the basin area and average annual precipitation over that area using a previously published regional regression equation. Based on tributary inputs, we estimate an average annual discharge for the Yukon River of 210 km3 year–1. This value is within 1% of the average measured annual discharge at the U.S. Geological Survey gaging station near the river terminus at Pilot Station, AK, for water years 2001 through 2005. Next, annual loads for 11 solutes are determined by combining annual discharge with point measurements of solute concentrations in tributary river water. Based on the sum of solutes in tributary water, we find that the Yukon River discharges approximately 33 million metric tons of dissolved solids each year at Pilot Station. Discharged solutes are dominated by cations calcium and magnesium (5.65 × 109 and 1.42 × 109 g year–1) and anions bicarbonate and sulphate (17.3 × 109 and 5.40 × 109 g year–1). These loads compare well with loads calculated independently at the three continuous gaging stations along the Yukon River. These findings show how annual solute yields vary throughout a major subarctic river basin and that accurate estimates of total river export can be determined from calculated tributary contributions.

  7. Climate change impact on the annual water balance in the northwest Florida coastal

    NASA Astrophysics Data System (ADS)

    Alizad, K.; Wang, D.; Alimohammadi, N.; Hagen, S. C.

    2012-12-01

    As the largest tributary to the Apalachicola River, the Chipola River originates in southern Alabama, flows through Florida Panhandle and ended to Gulf of Mexico. The Chipola watershed is located in an intermediate climate environment with aridity index around one. Watershed provides habitat for a number of threatened and endangered animal and plant species. However, climate change affects hydrologic cycle of Chipola River watershed at various temporal and spatial scales. Studying the effects of climate variations is of great importance for water and environmental management purposes in this catchment. This research is mainly focuses on assessing climate change impact on the partitioning pattern of rainfall from mean annual to inter-annual and to seasonal scales. At the mean annual scale, rainfall is partitioned into runoff and evaporation assuming negligible water storage changes. Mean annual runoff is controlled by both mean annual precipitation and potential evaporation. Changes in long term mean runoff caused by variations of long term mean precipitation and potential evaporation will be evaluated based on Budyko hypothesis. At the annual scale, rainfall is partitioned into runoff, evaporation, and storage change. Inter-annual variability of runoff and evaporation are mainly affected by the changes of mean annual climate variables as well as their inter-annual variability. In order to model and evaluate each component of water balance at the annual scale, parsimonious but reliable models, are developed. Budyko hypothesis on the existing balance between available water and energy supply is reconsidered and redefined for the sub-annual time scale and reconstructed accordingly in order to accurately model seasonal hydrologic balance of the catchment. Models are built in the seasonal time frame with a focus on the role of storage change in water cycle. Then for Chipola catchment, models are parameterized based on a sufficient time span of historical data and the

  8. Has water limited our imagination for aridland biogeochemistry?

    PubMed

    Austin, Amy T

    2011-05-01

    The classic ecological paradigm for deserts, that all processes are controlled by water availability, has limited our imagination for exploring other controls on the cycling of carbon and nutrients in aridland ecosystems. This review of recent studies identifies alternative mechanisms that challenge the idea that all soil processes in aridlands are proximately water-limited, and highlights the significance of photodegradation of aboveground litter and the overriding importance of spatial heterogeneity as a modulator of biotic responses to water availability. Aridlands currently occupy >30% of the terrestrial land surface and are expanding. It is therefore critical to incorporate these previously unappreciated mechanisms in our understanding of aridland biogeochemistry to mitigate the effects of desertification and global change.

  9. 77 FR 10977 - Fisheries of the Northeastern United States; Atlantic Herring Fishery; Sub-Annual Catch Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-24

    ... Northeastern United States; Atlantic Herring Fishery; Sub-Annual Catch Limit (ACL) Harvested for Management... January 1, 2013, when the 2013 sub-ACL for Area 1B becomes available, except when transiting as described in this notice. This action is based on the determination that the revised Atlantic herring...

  10. 77 FR 42192 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Comprehensive Annual Catch Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-18

    ... Amendment specified, in part, annual catch limits (ACLs) and accountability measures (AMs) for species in... Comprehensive ACL Amendment to revise the commercial and recreational sector ACLs for wreckfish and requested... ACLs for species in its FMPs at a level that may not exceed the fishing level recommendation of...

  11. 78 FR 59626 - Main Hawaiian Islands Deep 7 Bottomfish Annual Catch Limits and Accountability Measures for 2013-14

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-27

    ... Bottomfish Annual Catch Limits and Accountability Measures for 2013-14 AGENCY: National Marine Fisheries... of the Fishery Ecosystem Plan for the Hawaiian Archipelago are available from the Western Pacific..., taking into account the associated risk of overfishing. The MHI bottomfish fishing year started...

  12. Annual water-resources review, White Sands Missile Range: 1971

    USGS Publications Warehouse

    Cruz, R.R.

    1972-01-01

    This report presents water-resource information that was collected at White Sands Missile Range during 1971 and early 1972 by personnel of the U.S. Geological Survey, Water Resources Division. Data on ground-water pumpage and resulting water-level fluctuation, chemical quality, percipitation, and surface-water runoff are summarized in the report. The data were obtained as a result of the continuing water-resources basic-data collection program sponsored by the Facilities Engineering Directorate, White Sands Missile Range.

  13. Revegetation in China’s Loess Plateau is approaching sustainable water resource limits

    NASA Astrophysics Data System (ADS)

    Feng, Xiaoming; Fu, Bojie; Piao, Shilong; Wang, Shuai; Ciais, Philippe; Zeng, Zhenzhong; Lü, Yihe; Zeng, Yuan; Li, Yue; Jiang, Xiaohui; Wu, Bingfang

    2016-11-01

    Revegetation of degraded ecosystems provides opportunities for carbon sequestration and bioenergy production. However, vegetation expansion in water-limited areas creates potentially conflicting demands for water between the ecosystem and humans. Current understanding of these competing demands is still limited. Here, we study the semi-arid Loess Plateau in China, where the `Grain to Green’ large-scale revegetation programme has been in operation since 1999. As expected, we found that the new planting has caused both net primary productivity (NPP) and evapotranspiration (ET) to increase. Also the increase of ET has induced a significant (p < 0.001) decrease in the ratio of river runoff to annual precipitation across hydrological catchments. From currently revegetated areas and human water demand, we estimate a threshold of NPP of 400 +/- 5 g C m-2 yr-1 above which the population will suffer water shortages. NPP in this region is found to be already close to this limit. The threshold of NPP could change by -36% in the worst case of climate drying and high human withdrawals, to +43% in the best case. Our results develop a new conceptual framework to determine the critical carbon sequestration that is sustainable in terms of both ecological and socio-economic resource demands in a coupled anthropogenic-biological system.

  14. Antimicrobial nanomaterials as water disinfectant: applications, limitations and future perspectives.

    PubMed

    Hossain, Fahim; Perales-Perez, Oscar J; Hwang, Sangchul; Román, Félix

    2014-01-01

    Nanotechnology and its application is one of the rapidly developing sciences. As demand of fresh drinking water is increasing, nanotechnology can contribute noticeable development and improvement to water treatment process. Disinfection process is the last and most important step in water and wastewater treatment process. Some nanomaterials can be used as disinfectants due to their antimicrobial properties and reduce the possibility of harmful disinfection by-products (DBPs) formation during traditional disinfection process. A significant number of research efforts is done or going on to understand the mechanisms and enhance the efficiency of nanomaterials as antimicrobial agents, although it will take more time to understand the full potential of nanomaterials in this field. This review paper focuses on inactivation pathways of benign nanomaterials, their possible and probable application and limitations as disinfectants and future opportunities for their application in water cleaning processes.

  15. Multi-tissue analyses reveal limited inter-annual and seasonal variation in mercury exposure in an Antarctic penguin community.

    PubMed

    Brasso, Rebecka L; Polito, Michael J; Emslie, Steven D

    2014-10-01

    Inter-annual variation in tissue mercury concentrations in birds can result from annual changes in the bioavailability of mercury or shifts in dietary composition and/or trophic level. We investigated potential annual variability in mercury dynamics in the Antarctic marine food web using Pygoscelis penguins as biomonitors. Eggshell membrane, chick down, and adult feathers were collected from three species of sympatrically breeding Pygoscelis penguins during the austral summers of 2006/2007-2010/2011. To evaluate the hypothesis that mercury concentrations in penguins exhibit significant inter-annual variation and to determine the potential source of such variation (dietary or environmental), we compared tissue mercury concentrations with trophic levels as indicated by δ(15)N values from all species and tissues. Overall, no inter-annual variation in mercury was observed in adult feathers suggesting that mercury exposure, on an annual scale, was consistent for Pygoscelis penguins. However, when examining tissues that reflected more discrete time periods (chick down and eggshell membrane) relative to adult feathers, we found some evidence of inter-annual variation in mercury exposure during penguins' pre-breeding and chick rearing periods. Evidence of inter-annual variation in penguin trophic level was also limited suggesting that foraging ecology and environmental factors related to the bioavailability of mercury may provide more explanatory power for mercury exposure compared to trophic level alone. Even so, the variable strength of relationships observed between trophic level and tissue mercury concentrations across and within Pygoscelis penguin species suggest that caution is required when selecting appropriate species and tissue combinations for environmental biomonitoring studies in Antarctica.

  16. The strengths and limitations of national water policies for water 'security.' (Invited)

    NASA Astrophysics Data System (ADS)

    Gleick, P. H.

    2013-12-01

    Sustainable water practices and policies must emerge at local, watershed, and national levels. The appropriate scale and type of policy will depend on scientific data and information, economic and institutional factors, and political will. Recent advances in hydroclimatic tools suggest the importance and limitations of national policies for monitoring, assessing, and managing freshwater resources. These tools include remote sensing of key hydroclimatic variables, multi-scale models for integrating hydrology and water management, technologies for enhancing water supply or improving water-use productivity, and theoretical approaches for developing sustainable water policies, including the concepts of 'peak water,' the 'soft path for water,' and integrated water resources management. This talk will address the scientific tools as well as the appropriate policies and strategies at different geographical scales critical for 21st century sustainable water management. The issue of 'zombie' water projects will also be addressed along with their role in national water strategies in the US, China, Africa, and elsewhere.

  17. The SPARC water vapour assessment II: comparison of annual, semi-annual and quasi-biennial variations in stratospheric and lower mesospheric water vapour observed from satellites

    NASA Astrophysics Data System (ADS)

    Lossow, Stefan; Khosrawi, Farahnaz; Nedoluha, Gerald E.; Azam, Faiza; Bramstedt, Klaus; Burrows, John. P.; Dinelli, Bianca M.; Eriksson, Patrick; Espy, Patrick J.; García-Comas, Maya; Gille, John C.; Kiefer, Michael; Noël, Stefan; Raspollini, Piera; Read, William G.; Rosenlof, Karen H.; Rozanov, Alexei; Sioris, Christopher E.; Stiller, Gabriele P.; Walker, Kaley A.; Weigel, Katja

    2017-03-01

    In the framework of the second SPARC (Stratosphere-troposphere Processes And their Role in Climate) water vapour assessment (WAVAS-II), the amplitudes and phases of the annual, semi-annual and quasi-biennial variation in stratospheric and lower mesospheric water were compared using 30 data sets from 13 different satellite instruments. These comparisons aimed to provide a comprehensive overview of the typical uncertainties in the observational database which can be considered in subsequent observational and modelling studies. For the amplitudes, a good agreement of their latitude and altitude distribution was found. Quantitatively there were differences in particular at high latitudes, close to the tropopause and in the lower mesosphere. In these regions, the standard deviation over all data sets typically exceeded 0.2 ppmv for the annual variation and 0.1 ppmv for the semi-annual and quasi-biennial variation. For the phase, larger differences between the data sets were found in the lower mesosphere. Generally the smallest phase uncertainties can be observed in regions where the amplitude of the variability is large. The standard deviations of the phases for all data sets were typically smaller than a month for the annual and semi-annual variation and smaller than 5 months for the quasi-biennial variation. The amplitude and phase differences among the data sets are caused by a combination of factors. In general, differences in the temporal variation of systematic errors and in the observational sampling play a dominant role. In addition, differences in the vertical resolution of the data, the considered time periods and influences of clouds, aerosols as well as non-local thermodynamic equilibrium (NLTE) effects cause differences between the individual data sets.

  18. Accuracy limit of rigid 3-point water models

    NASA Astrophysics Data System (ADS)

    Izadi, Saeed; Onufriev, Alexey V.

    2016-08-01

    Classical 3-point rigid water models are most widely used due to their computational efficiency. Recently, we introduced a new approach to constructing classical rigid water models [S. Izadi et al., J. Phys. Chem. Lett. 5, 3863 (2014)], which permits a virtually exhaustive search for globally optimal model parameters in the sub-space that is most relevant to the electrostatic properties of the water molecule in liquid phase. Here we apply the approach to develop a 3-point Optimal Point Charge (OPC3) water model. OPC3 is significantly more accurate than the commonly used water models of same class (TIP3P and SPCE) in reproducing a comprehensive set of liquid bulk properties, over a wide range of temperatures. Beyond bulk properties, we show that OPC3 predicts the intrinsic charge hydration asymmetry (CHA) of water — a characteristic dependence of hydration free energy on the sign of the solute charge — in very close agreement with experiment. Two other recent 3-point rigid water models, TIP3PFB and H2ODC, each developed by its own, completely different optimization method, approach the global accuracy optimum represented by OPC3 in both the parameter space and accuracy of bulk properties. Thus, we argue that an accuracy limit of practical 3-point rigid non-polarizable models has effectively been reached; remaining accuracy issues are discussed.

  19. Accuracy limit of rigid 3-point water models.

    PubMed

    Izadi, Saeed; Onufriev, Alexey V

    2016-08-21

    Classical 3-point rigid water models are most widely used due to their computational efficiency. Recently, we introduced a new approach to constructing classical rigid water models [S. Izadi et al., J. Phys. Chem. Lett. 5, 3863 (2014)], which permits a virtually exhaustive search for globally optimal model parameters in the sub-space that is most relevant to the electrostatic properties of the water molecule in liquid phase. Here we apply the approach to develop a 3-point Optimal Point Charge (OPC3) water model. OPC3 is significantly more accurate than the commonly used water models of same class (TIP3P and SPCE) in reproducing a comprehensive set of liquid bulk properties, over a wide range of temperatures. Beyond bulk properties, we show that OPC3 predicts the intrinsic charge hydration asymmetry (CHA) of water - a characteristic dependence of hydration free energy on the sign of the solute charge - in very close agreement with experiment. Two other recent 3-point rigid water models, TIP3PFB and H2ODC, each developed by its own, completely different optimization method, approach the global accuracy optimum represented by OPC3 in both the parameter space and accuracy of bulk properties. Thus, we argue that an accuracy limit of practical 3-point rigid non-polarizable models has effectively been reached; remaining accuracy issues are discussed.

  20. Amyloid Fibrillation of Insulin under Water-Limited Conditions

    PubMed Central

    Choi, Tae Su; Lee, Jong Wha; Jin, Kyeong Sik; Kim, Hugh I.

    2014-01-01

    Amyloid fibrillation in water-organic mixtures has been widely studied to understand the effect of protein-solvent interactions on the fibrillation process. In this study, we monitored insulin fibrillation in formamide and its methyl derivatives (formamide, N-methyl formamide, N,N-dimethyl formamide) in the presence and absence of water. These model solvent systems mimic the cellular environment by providing denaturing conditions and a hydrophobic environment with limited water content. Thioflavin T (ThT) assay revealed that binary mixtures of water with formamide and its methyl derivatives enhanced fibrillation rates and β-sheet abundance, whereas organic solvents suppressed insulin fibrillation. We utilized solution small-angle x-ray scattering (SAXS) and differential scanning calorimetry (DSC) to investigate the correlation between protein-solvent interactions and insulin fibrillation. SAXS experiments combined with simulated annealing of the protein indicated that the degree of denaturation of the hydrophobic core region at residues B11–B17 determines the fibrillation rate. In addition, DSC experiments suggested a crucial role of hydrophobic interactions in the fibrillation process. These results imply that an environment with limited water, which imitates a lipid membrane system, accelerates protein denaturation and the formation of intermolecular hydrophobic interactions during amyloid fibrillation. PMID:25418175

  1. Global water resources assessment at a sub-annual timescale: Application to climate change impact assessment

    NASA Astrophysics Data System (ADS)

    Yamamoto, T.; Hanasaki, N.; Takahashi, K.; Hijioka, Y.

    2010-12-01

    Several reports have assessed water scarcity globally using the widely accepted withdrawal-to-water resources ratio (hereafter WWR). This index is defined as the ratio of annual withdrawal to the annual renewable water resources (runoff). The index has also been used widely to assess the impact of climate change on global water resources. Here, we ask whether it is appropriate to use the WWR to assess the impact of climate change. Global warming is projected to increase the mean annual runoff in many parts of the world. Therefore, in these regions, the WWR decreases, by definition. However, water scarcity may not always be alleviated in these regions. Global warming is also projected to increase the temporal and spatial variability of precipitation, decrease snowfall, and change the timing of snowmelt. These phenomena may increase the temporal gap between water availability and water demand, which might worsen local water scarcity, even if the mean annual runoff is increased. To assess the impact of climate change on global water resources incorporating subannual time-scale phenomena, this study applies a new water scarcity index, the cumulative withdrawal-to-demand ratio (hereafter CWD). This index is defined as the ratio of the accumulation of daily water withdrawal from local water resources to the accumulation of daily water demand. To estimate daily water withdrawal and water demand, we used the state-of-the-art H08 global water resources model. Our results indicated that global warming increased the mean annual runoff in 52% of the total land area globally. However, in 22% of the area where runoff increased, the CWD showed increased water stress. Those regions included India, northern China, and northern Europe. For India, the increase in water stress was attributed to the seasonal gap between runoff increase and water demand. The increased runoff was concentrated in a few months, while the high water demand months differed and were much longer. For Europe

  2. 50 CFR 622.41 - Annual catch limits (ACLs), annual catch targets (ACTs), and accountability measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ACL based on a moving multi-year average of landings, as described in the FMP. (c) Other shallow-water....775 million kg) for 2015 and subsequent fishing years. (e) Red grouper—(1) Commercial sector. The IFQ... commercial red grouper. The applicable commercial ACL for red grouper, in gutted weight, for 2012...

  3. Century-scale variability in global annual runoff examined using a water balance model

    USGS Publications Warehouse

    McCabe, G.J.; Wolock, D.M.

    2011-01-01

    A monthly water balance model (WB model) is used with CRUTS2.1 monthly temperature and precipitation data to generate time series of monthly runoff for all land areas of the globe for the period 1905 through 2002. Even though annual precipitation accounts for most of the temporal and spatial variability in annual runoff, increases in temperature have had an increasingly negative effect on annual runoff after 1980. Although the effects of increasing temperature on runoff became more apparent after 1980, the relative magnitude of these effects are small compared to the effects of precipitation on global runoff. ?? 2010 Royal Meteorological Society.

  4. Water Science and Technology Board. Annual report 1993-1994

    SciTech Connect

    Not Available

    1995-01-01

    This report summarizes the activities of the Water Science and Technology Board during 1993-1994. The WSTB is intended to be a dynamic forum, a mechanism by which the broad community of water science, technology, and policy professionals can help assure high-quality national water programs. The principal products of WSTB studies are written reports which cover a wide range of water resources issues of current national concern. A few recent examples are: Alternatives for ground water cleanup; Managing wastewater in coastal urban areas; and, Water transfers in the West - efficiency, equity and the environment. Projects completed, ongoing studies and published reports are described in detail in their respective sections of this report.

  5. Water Science and Technology Board. Annual report 1992-1993

    SciTech Connect

    Not Available

    1995-01-01

    This report summarizes the activities of the Water Science and Technology Board during 1992. The WSTB is intended to be a dynamic forum, a mechanism by which the broad community of water science, technology, and policy professionals can help assure high-quality national water programs. The principal products of WSTB studies are written reports which cover a wide range of water resources issues of current national concern. A few recent examples are: Managing wastewater in coastal urban areas; Ground water vulnerability assessment; Water transfers in the West - efficiency, equity and the environment; and Opportunities in the hydrologic sciences. Projects completed, ongoing studies and published reports are described in detail in their respective sections of this report.

  6. Water Science and Technology Board. Annual report 1991

    SciTech Connect

    Not Available

    1995-01-01

    This report summarizes the activities of the Water Science and Technology Board during 1991. The WSTB is intended to be a dynamic forum, a mechanism by which the broad community of water science, technology, and policy professionals can help assure high-quality national water programs. The principal products of WSTB studies are written reports which cover a wide range of water resources issues of current national concern. A few recent examples are: Restoration of aquatic ecosystems - science, technologies and public policy; Water transfers in the West - efficiency, equity and the environment; Opportunities in the hydrologic sciences; and Ground water models - scientific and regulatory applications. Projects completed, ongoing studies and published reports are described in detail in their respective sections of this report.

  7. Beyond annual streamflow reconstructions for the Upper Colorado River Basin: A paleo-water-balance approach

    NASA Astrophysics Data System (ADS)

    Gangopadhyay, Subhrendu; McCabe, Gregory J.; Woodhouse, Connie A.

    2015-12-01

    In this paper, we present a methodology to use annual tree-ring chronologies and a monthly water balance model to generate annual reconstructions of water balance variables (e.g., potential evapotranspiration (PET), actual evapotranspiration (AET), snow water equivalent (SWE), soil moisture storage (SMS), and runoff (R)). The method involves resampling monthly temperature and precipitation from the instrumental record directed by variability indicated by the paleoclimate record. The generated time series of monthly temperature and precipitation are subsequently used as inputs to a monthly water balance model. The methodology is applied to the Upper Colorado River Basin, and results indicate that the methodology reliably simulates water-year runoff, maximum snow water equivalent, and seasonal soil moisture storage for the instrumental period. As a final application, the methodology is used to produce time series of PET, AET, SWE, SMS, and R for the 1404-1905 period for the Upper Colorado River Basin.

  8. Interactions between plant nutrients, water and carbon dioxide as factors limiting crop yields

    PubMed Central

    Gregory, P. J.; Simmonds, L. P.; Warren, G. P.

    1997-01-01

    Biomass production of annual crops is often directly proportional to the amounts of radiation intercepted, water transpired and nutrients taken up. In many places the amount of rainfall during the period of rapid crop growth is less than the potential rate of evaporation, so that depletion of stored soil water is commonplace. The rate of mineralization of nitrogen (N) from organic matter and the processes of nutrient loss are closely related to the availability of soil water. Results from Kenya indicate the rapid changes in nitrate availability following rain.
    Nutrient supply has a large effect on the quantity of radiation intercepted and hence, biomass production. There is considerable scope for encouraging canopy expansion to conserve water by reducing evaporation from the soil surface in environments where it is frequently rewetted, and where the unsaturated hydraulic conductivity of the soil is sufficient to supply water at the energy limited rate (e.g. northern Syria). In regions with high evaporative demand and coarse-textured soils (e.g. Niger), transpiration may be increased by management techniques that reduce drainage.
    Increases in atmospheric [CO2] are likely to have only a small impact on crop yields when allowance is made for the interacting effects of temperature, and water and nutrient supply.

  9. Effects of Spatial Variability on Annual Average Water Balance

    NASA Astrophysics Data System (ADS)

    Milly, P. C. D.; Eagleson, P. S.

    1987-11-01

    Spatial variability of soil and vegetation causes spatial variability of the water balance. For an area in which the water balance is not affected by lateral water flow, the frequency distributions of storm surface runoff, evapotranspiration, and drainage to groundwater are derivable from distributions of soil hydraulic parameters by means of a point water balance model and local application of the vegetal equilibrium hypothesis. Means and variances of the components of the budget can be found by Monte Carlo simulation or by approximate local expansions. For a fixed set of mean soil parameters, soil spatial variability may induce significant changes in the areal mean water balance, particularly if storm surface runoff occurs. Variability of the pore size distribution index and permeability has a much larger effect than that of effective porosity on the means and variances of water balance variables. The importance of the pore size distribution index implies that the microscopic similarity assumption may underestimate the effects of soil spatial variability. In general, the presence of soil variability reduces the sensitivity of water balance to mean properties. For small levels of soil variability, there exists a unique equivalent homogeneous soil type that reproduces the budget components and the mean soil moisture saturation of an inhomogeneous area.

  10. Water Science and Technology Board annual report, 1990

    SciTech Connect

    Not Available

    1990-12-31

    This report summarizes the activities of the Water Science and Technology Board (WSTB) during 1990, its eighth year of existence. It describes current and recently completed projects, new activities scheduled to begin in 1991, and plans for the future. The WSTB is intended to be a dynamic forum, a mechanism by which the board community of water science, technology, and policy professionals can help assure high-quality national water programs. As such, the Board considers out-reach and communications of much importance.

  11. Water Science and Technology Board annual report, 1990

    SciTech Connect

    Not Available

    1990-01-01

    This report summarizes the activities of the Water Science and Technology Board (WSTB) during 1990, its eighth year of existence. It describes current and recently completed projects, new activities scheduled to begin in 1991, and plans for the future. The WSTB is intended to be a dynamic forum, a mechanism by which the board community of water science, technology, and policy professionals can help assure high-quality national water programs. As such, the Board considers out-reach and communications of much importance.

  12. Water Activity Limits the Hygroscopic Growth Factor of Organic Aerosols

    NASA Astrophysics Data System (ADS)

    Rodriguez, L. I.; Cabrera, J. A.; Golden, D.; Tabazadeh, A.

    2007-12-01

    In this work we study the hygroscopic behavior of organic aerosols, which has important implications for Earth's climate. The hygroscopic growth factor (HGF) is defined as the ratio of the diameter of a spherical particle when it is exposed to dry conditions to that at humid conditions. We present a new formulation to express the HGF of an aerosol particle as a function of water activity (aw) in the aqueous phase. This new formulation matches reported HGFs for common inorganic salts and water-miscible organic particles that are known to deliquesce into aqueous drops at high relative humidities (RH). Many studies use tandem differential mobility analyzers (TDMA) to determine the HGF of organic aerosols. For example, Brooks et al. used a TDMA to measure a HGF of 1.2 for 2 μm phthalic acid (PA) particles at 90% RH (aw= 0.9). However, water activity limits the growth of a particle that can be attributed to water uptake. We have assembled a vapor pressure apparatus to measure aw of aqueous solutions at room temperature. Measured water activities for PA, used in our growth formulation, yield a HGF of ~ 1.0005 for 2 μm PA particles at 90% RH. Comparing our results against Brooks et al. suggests that TDMA experiments may grossly overestimate the HGF of PA particles since water activity limits this growth to below 1.0005. Alternatively, we suggest that the adsorption of a negligible mass of water by a highly porous PA particle can lead to an apparent growth in particle size by changing its morphology. Other studies also use TDMAs to measure HGFs of secondary organic aerosols (SOAs). HGFs reported for SOAs are very similar to PA, suggesting that the observed growth may be due to morphological changes in particle size rather than water uptake as commonly assumed. We built a smog chamber where an organic precursor, such as d-limonene, reacts with nitrogen oxides under UV radiation to produce SOAs. We compare the HGFs for SOAs obtained with our method to those obtained with

  13. Spacebased Observations of Oceanic Influence on the Annual Variation of South American Water Balance

    NASA Technical Reports Server (NTRS)

    Liu, W. Timothy; Xie, Xiaosu; Tang, Wenqing; Zlotnicki, Victor

    2006-01-01

    The mass change of South America (SA) continent measured by the Gravity Recovery and Climate Experiment (GRACE) imposes a constraint on the uncertainties in estimating the annual variation of rainfall measured by Tropical Rain Measuring Mission (TRMM) and ocean moisture influx derived from QuikSCAT data. The approximate balance of the mass change rate with the moisture influx less climatological river discharge, in agreement with the conservation principle, bolsters not only the credibility of the spacebased measurements, but supports the characterization of ocean's influence on the annual variation of continental water balance. The annual variation of rainfall is found to be in phase with the mass change rate in the Amazon and the La Plata basins, and the moisture advection across relevant segments of the Pacific and Atlantic coasts agrees with the annual cycle of rainfall in the two basins and the Andes mountains.

  14. A view of annual water quality cycle and inter-annual variations in agricultural headwater catchment (Kervidy-Naizin, France)

    NASA Astrophysics Data System (ADS)

    Aubert, A.; Gascuel-odoux, C.; Merot, P.; Grimaldi, C.; Gruau, G.; Ruiz, L.

    2011-12-01

    Climatic conditions impact biotransformation and transfer of solutes. Therefore, they modify solute emissions in streams. Studying these modifications requires long term and detailed monitoring of both internal processes and river loads, which are rarely combined. The Kervidy-Naizin catchment, implemented in 1993, is part of the French network of catchment for environmental research (SOERE RBV, focused on the Critical Zone). It is an intensive agricultural catchment located in a temperate climate in Western France (Brittany) (Molenat et al., 2008; Morel et al., 2009). It presents shallow aquifers due to impervious bedrock. Both hydrology and water chemistry are monitored with a daily time step since 2000-01, as well as possible explanatory data (land use, meteorology, etc.). Concentrations in major anions in this catchment are extremely high, which make people call it a "saturated" catchment. We identified annual patterns for chloride, sulphate, dissolved organic and inorganic carbon and nitrate concentration variations. First, we considered the complete set of concentration data as function of the time. From that, we foresaw 3 cyclic temporal patterns. Then, from representing the concentrations as function of meteorological parameters, intra-annual hysteretic variations and their inter-annual variations were clearly identified. Our driving question is to know if and how climatic conditions are responsible for variations of the patterns in and between years. In winter, i.e. rainy and cold period, rainfall is closely linked to discharge because of a direct recharge to the shallow groundwater. Reversely, in transition periods (spring and fall) and hot periods, both rainfall and temperature influences discharge in relation to their range of variations. Moreover, biological processes, driven by temperature and wetness, also act during these periods. On the whole, we can emphasize the specificity of water chemistry patterns for each element. Noticeable differences

  15. Forests in a water limited world under climate change

    NASA Astrophysics Data System (ADS)

    Mátyás, Csaba; Sun, Ge

    2014-08-01

    The debate on ecological and climatic benefits of planted forests at the sensitive dry edge of the closed forest belt (i.e. at the ‘xeric limits’) is still unresolved. Forests sequester atmospheric carbon dioxide, accumulate biomass, control water erosion and dust storms, reduce river sedimentation, and mitigate small floods. However, planting trees in areas previously dominated by grassland or cropland can dramatically alter the energy and water balances at multiple scales. The forest/grassland transition zone is especially vulnerable to projected drastic temperature and precipitation shifts and growing extremes due to its high ecohydrological sensitivity. We investigated some of the relevant aspects of the ecological and climatic role of forests and potential impacts of climate change at the dryland margins of the temperate-continental zone using case studies from China, the United States and SE Europe (Hungary). We found that, contrary to popular expectations, the effects of forest cover on regional climate might be limited and the influence of forestation on water resources might be negative. Planted forests generally reduce stream flow and lower groundwater table level because of higher water use than previous land cover types. Increased evaporation potential due to global warming and/or extreme drought events is likely to reduce areas that are appropriate for tree growth and forest establishment. Ecologically conscious forest management and forestation planning should be adjusted to the local, projected hydrologic and climatic conditions, and should also consider non-forest alternative land uses.

  16. Role of detection limits in drinking water regulation.

    PubMed

    Calder, Ryan S D; Schmitt, Ketra A

    2010-11-01

    Some commentators on environmental science and policy have claimed that advances in analytical chemistry, reflected by an ability to detect contaminants at ever-decreasing concentrations, lead to regulations stricter than justified by available toxicological data. We evaluate this claim in the context of drinking water regulation, with respect to contaminants regulated under the Safe Drinking Water Act (SDWA). We examine the relationships between historical and present maximum contaminant levels and goals in the greater context of detection capability and evaluate the extent to which different aspects of the regulatory apparatus (i.e., analytical capability, cost-benefit analysis, analysis of competing risks, and available toxicological data) influence the regulatory process. Our findings do not support the claim that decreases in detection limit lead to more stringent regulation in the context of drinking water regulation in the United States. Further, based on our analysis of the National Primary Drinking Water Regulation and existing United States Environmental Protection Agency approaches to establishing the practical quantifiable level, we conclude that in the absence of changes to the underlying toxicological model, regulatory revision is unlikely.

  17. Detection limits of organic contaminants in drinking water

    SciTech Connect

    Draper, W.M.; Dhoot, J.S.; Dhaliwal, J.S.; Remoy, J.W.; Perera, S.K.; Baumann, F.J.

    1998-06-01

    This article examines some of the experimental variables that can contribute to the observed variability in laboratory performance. The examples provided suggest that method detection limits (MDLs) would be more uniform among laboratories if (1) uniform spike concentrations were used in MDL determination; (2) analytical methods were more uniform as to procedures, reagents, and materials; and (3) tighter guidelines were established for conducting MDL experiments and handling MDL data. The pooling of data from multiple spike levels (or any other means to increase sample size) minimizes random error in MDL determination. Improved control in MDL determination would lead to better information on laboratory capabilities, and this in turn would improve the technical basis for reporting limits, trigger levels, and water quality standards.

  18. 29 CFR 2590.715-2711 - No lifetime or annual limits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (c) of this section). (2) Condition-based exclusions. The rules of this section do not prevent a..., DEPARTMENT OF LABOR GROUP HEALTH PLANS RULES AND REGULATIONS FOR GROUP HEALTH PLANS Other Requirements § 2590.... (2) Annual limits—(i) General rule. Except as provided in paragraphs (a)(2)(ii), (b), and (d) of...

  19. 29 CFR 2590.715-2711 - No lifetime or annual limits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (c) of this section). (2) Condition-based exclusions. The rules of this section do not prevent a..., DEPARTMENT OF LABOR GROUP HEALTH PLANS RULES AND REGULATIONS FOR GROUP HEALTH PLANS Other Requirements § 2590.... (2) Annual limits—(i) General rule. Except as provided in paragraphs (a)(2)(ii), (b), and (d) of...

  20. 50 CFR 648.70 - Surfclam and ocean quahog Annual Catch Limit (ACL).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Surfclam and ocean quahog Annual Catch... Management Measures for the Atlantic Surf Clam and Ocean Quahog Fisheries § 648.70 Surfclam and ocean quahog... ocean quahog fisheries, which shall be equal to the ABCs recommended by the SSC. (1) Sectors....

  1. 50 CFR 648.70 - Surfclam and ocean quahog Annual Catch Limit (ACL).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Surfclam and ocean quahog Annual Catch... Management Measures for the Atlantic Surf Clam and Ocean Quahog Fisheries § 648.70 Surfclam and ocean quahog... ocean quahog fisheries, which shall be equal to the ABCs recommended by the SSC. (1) Sectors....

  2. 50 CFR 648.70 - Surfclam and ocean quahog Annual Catch Limit (ACL).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Surfclam and ocean quahog Annual Catch... Management Measures for the Atlantic Surf Clam and Ocean Quahog Fisheries § 648.70 Surfclam and ocean quahog... ocean quahog fisheries, which shall be equal to the ABCs recommended by the SSC. (1) Sectors....

  3. 50 CFR 648.100 - Summer flounder Annual Catch Limit (ACL).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) The Summer Flounder Monitoring Committee shall recommend to the MAFMC separate ACLs for the commercial... recommended by the SSC. (1) Sector allocations. The commercial and recreational fishing sector ACLs will be... sector ACLs may be established on an annual basis for up to 3 years at a time, dependent on whether...

  4. 50 CFR 648.100 - Summer flounder Annual Catch Limit (ACL).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) The Summer Flounder Monitoring Committee shall recommend to the MAFMC separate ACLs for the commercial... recommended by the SSC. (1) Sector allocations. The commercial and recreational fishing sector ACLs will be... sector ACLs may be established on an annual basis for up to 3 years at a time, dependent on whether...

  5. 50 CFR 648.100 - Summer flounder Annual Catch Limit (ACL).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) The Summer Flounder Monitoring Committee shall recommend to the MAFMC separate ACLs for the commercial... recommended by the SSC. (1) Sector allocations. The commercial and recreational fishing sector ACLs will be... sector ACLs may be established on an annual basis for up to 3 years at a time, dependent on whether...

  6. Shallow water equations: viscous solutions and inviscid limit

    NASA Astrophysics Data System (ADS)

    Chen, Gui-Qiang; Perepelitsa, Mikhail

    2012-12-01

    We establish the inviscid limit of the viscous shallow water equations to the Saint-Venant system. For the viscous equations, the viscosity terms are more degenerate when the shallow water is close to the bottom, in comparison with the classical Navier-Stokes equations for barotropic gases; thus, the analysis in our earlier work for the classical Navier-Stokes equations does not apply directly, which require new estimates to deal with the additional degeneracy. We first introduce a notion of entropy solutions to the viscous shallow water equations and develop an approach to establish the global existence of such solutions and their uniform energy-type estimates with respect to the viscosity coefficient. These uniform estimates yield the existence of measure-valued solutions to the Saint-Venant system generated by the viscous solutions. Based on the uniform energy-type estimates and the features of the Saint-Venant system, we further establish that the entropy dissipation measures of the viscous solutions for weak entropy-entropy flux pairs, generated by compactly supported C 2 test-functions, are confined in a compact set in H -1, which yields that the measure-valued solutions are confined by the Tartar-Murat commutator relation. Then, the reduction theorem established in Chen and Perepelitsa [5] for the measure-valued solutions with unbounded support leads to the convergence of the viscous solutions to a finite-energy entropy solution of the Saint-Venant system with finite-energy initial data, which is relative with respect to the different end-states of the bottom topography of the shallow water at infinity. The analysis also applies to the inviscid limit problem for the Saint-Venant system in the presence of friction.

  7. Annual ground-water use in the Twin Cities metropolitan area, Minnesota, 1970-79

    USGS Publications Warehouse

    Horn, M.A.

    1984-01-01

    Annual ground-water use in the Twin Cities Metropolitan Area from 1970-79 is presented by aquifer and type of use. The data show that most ground water is withdrawn from wells in the Prairie du Chien-Jordan aquifer and that major uses of the water are for self-supplied industry and public supplies. Annual ground-water-use data are presented by county for each of the five major aquifers; Prairie du Chien-Jordan, Mount Simon-Hinckley, Ironton-Galesville, St. Peter, and drift. The data also are presented by county for each major use type, including public supply, self-supplied industry, commercial air-conditioning, irrigation, lake-level maintenance, and dewatering. The data were collected initially by the Minnesota Department of Natural Resources and were supplemented by data collected by the U.S. Geological Survey.

  8. Long term mean annual water temperature for stream reaches in Pacific Northwest United States

    USGS Publications Warehouse

    ,

    2012-01-01

    Long-term mean annual water temperature (degrees Celsius) was estimated for the E2RF1 stream network (Brakebill and Terziotti, 2011) located within the Pacific Northwest region of the United States (HUC2 = 17; the Columbia River basin, the Puget Sound watershed, the coastal drainages of Washington and Oregon, and the closed basins in southern Oregon). Multiple linear regressions were used to select reach-scale watershed attributes (explanatory variables) for predicting the long-term mean annual water temperature (dependent variable) at a set of USGS water-quality monitoring stations. The results from the multiple linear regressions were used to predict the long-term mean water temperature for the Pacific Northwest reaches in the E2RF1 network.

  9. Does the rhizosphere hydrophobicity limit root water uptake?

    NASA Astrophysics Data System (ADS)

    Zare, Mohsen; Ahmed, Mutez; Kroener, Eva; Carminati, Andrea

    2015-04-01

    The ability of plants to extract water from the soil is influenced by the hydraulic conductivity of roots and their rhizosphere. Recent experiments showed that the rhizosphere turned hydrophobic after drying and it remained dry after rewetting [1]. Our objective was to investigate whether rhizosphere hydrophobicity is a limit to root water uptake after drying. To quantify the effect of rhizosphere hydrophobicity on root water uptake, we used neutron radiography to trace the transport of deuterated water (D2O) in the roots of lupines experiencing a severe, local soil drying. The plants were grown in aluminum containers (30×30×1 cm) filled with sandy soil. The soil was partitioned into nine compartments using three horizontal and three vertical layers of coarse sand (thickness of 1cm) as capillary barrier. When the plants were 28 days old, we let one of the upper lateral compartments dry to a water content of 2-4%, while keeping the other compartments to a water content of 20%. Then we injected 10 ml of D2O in the dry compartment and 10 ml in the symmetric location. The radiographs showed that root water uptake in the soil region that was let dry and then irrigated was 4-8 times smaller than in the wet soil region[2]. In a parallel experiment, we used neutron radiography to monitor the rehydration of lupine roots that were irrigated after a severe drying experiment. Based on root swelling and additional data on the xylem pressure, we calculated the hydraulic conductivity of the root-rhizosphere continuum. We found that the hydraulic conductivity of the root-rhizosphere continuum was initially 5.75×10-14 m s-1and it increased to 4.26×10-12 m s-1after four hours. Both experiments show that rhizosphere hydrophobicity after drying is associated with a reduction in root water uptake and a big decrease in hydraulic conductivity of the soil-root system. [1] Carminati et al (2010) Plant and Soil. Vol. 332: 163-176. [2] Zarebanadkouki and Carmianti (2013) Journal of Plant

  10. The 13th Annual James L. Waters Symposium at Pittcon: Electron Spectroscopy for Chemical Analysis

    NASA Astrophysics Data System (ADS)

    Baltrus, John P.

    2004-12-01

    The 13th Annual James L. Waters Symposium focused on a review of the origin, development, implementation, and commercialization of electron spectroscopy for chemical analysis by four of the pioneers in the field. The subsequent articles summarize the presentations made in that symposium.

  11. The 13th Annual James L. Waters Symposium at Pittcon: Electron Spectroscopy for Chemical Analysis

    ERIC Educational Resources Information Center

    Baltrus, John P.

    2004-01-01

    The objective of the James L. Waters Annual Symposium is to recognize pioneers in the development of instrumentation by preserving the early history of the cooperation and important contributions of inventors, scientists, engineers, entrepreneurs, and marketing organizations. The symposium was held in Pittsburgh, United States in March 2002 to…

  12. The 14th Annual James L. Waters Symposium at Pittcon: Raman Spectroscopy

    ERIC Educational Resources Information Center

    Gardner, Charles W.

    2007-01-01

    Raman Spectroscopy was the main topic of the 14th Annual James L. Waters Symposium, which was held in March 2003 at Pittcon. The development of the enabling technologies that have made Raman spectroscopy a routine analysis tool in many laboratories worldwide is discussed.

  13. A water use and growth model for Eucalyptus plantation in water-limited conditions

    SciTech Connect

    Calder, I.R.

    1992-12-31

    To investigate the environmental impact of plantation forestry using fast-growing tree species in southern India, a program of field studies was initiated in 1987 specifically to measure the water use, nutrient uptake and growth rates of the plantations. A water use and growth (WAG) model is proposed for calculating transpiration and growth of Eucalyptus plantation in water-limited conditions. The model is based on the measured relationships between transpiration rate and basal cross-sectional area and soil moisture availability. The volume growth rate (in water-limited conditions) is assumed to be proportional to the volume of water transpired. The model is calibrated using (deuterium tracing) measurements of transpiration and measurements of growth recorded at the Puradal experimental plantation, Karnataka, southern India.

  14. Plasma generation in mass-limited water targets

    NASA Astrophysics Data System (ADS)

    Hah, Jungmoo; Liberty, Kirk; Nees, John; Krushelnick, Karl; Thomas, Alexander

    2014-10-01

    One major problem associated with high repetition-rate experiment is obtaining a suitable new target for each shot, while maintaining shot-to-shot spatial stability. For high repetition-rate laser experiments with solid targets, rotating stage is usually used for moving a target point, which causes stability and size problems. To solve these problems, some researchers have tried to replace solid targets with liquid stream or droplet. Here, we use a syringe pump, a piezoelectric device and a tungsten needle to make continuous and stable water droplets with a diameter of ~ 2 μm. These mass-limited water droplets as a target have some advantages. First, heat dissipation is blocked, so the target is entirely heated. Second, effective spatial contrast is improved by reducing the interaction between lower intensity spatial wings of the beam and a single-micron target. Third, at the relativistic laser intensities, a smaller target allows for higher electron densities at the target's back surface, which enhances field's strength for ion acceleration. For these advantages, it is required that we understand plasma generation processes. Therefore, we investigate the processes by irradiating fs laser pulses to mass-limited droplets and these interactions are captured by CCD.

  15. Pesticides water decontamination in oxygen-limited conditions.

    PubMed

    Suciu, Nicoleta Alina; Ferrari, Federico; Vasileiadis, Sotirios; Merli, Annalisa; Capri, Ettore; Trevisan, Marco

    2013-01-01

    This study was undertaken to develop a laboratory bioreactor, with a functioning principle similar with that of biobed systems but working in oxygen-limited conditions, suitable for decontaminating wastewater mixtures with pesticides. The system is composed by two cylindrical plastic containers. The first one, where the pesticides solution is collected, is open, whereas the second one, where the biomass is disposed, is closed. The pesticides solution was pumped at the biomass surface and subsequently recollected and disposed in the first container. Four pesticides with different physical-chemical characteristics were tested. The results obtained showed a relatively good capacity of the developed prototype to decontaminate waste water containing the mixture of pesticides. The time of the experiment, the number of cycles that the solution made in the system and the environmental temperature have a significantly influence for the decontamination of acetochlor and chlorpyrifos whereas for the decontamination of terbuthylazine and metalaxyl no significant influence was observed. Even if the present prototype could represent a valid solution to manage the water pesticides residues in a farm and to increase the confidence of bystanders and residents, the practical difficulties when replacing the biomass could represent a limit of the system.

  16. The annual cycle of water vapor on Mars as observed by the Thermal Emission Spectrometer

    NASA Astrophysics Data System (ADS)

    Smith, M. D.

    2001-12-01

    We report here on the latitude, longitude, and seasonal dependence of water vapor abundance for over one full Martian year as observed by the Mars Global Surveyor Thermal Emission Spectrometer (TES). A maximum in water vapor abundance is observed at high latitudes during mid-summer in both hemispheres, reaching a maximum value of ~100 pr-μ m in the north and ~50 pr-μ m in the south. Low water vapor abundance (<5 pr-μ m) is observed at middle and high latitudes in the fall and winter of both hemispheres. There are large differences in the hemispheric (north versus south) and seasonal (perihelion versus aphelion) behavior of water vapor. The latitudinal and seasonal dependence of the decay of the northern summer water vapor maximum implies cross-equatorial transport of water to the southern hemisphere, while there is little or no corresponding transport during the decay of the southern hemisphere summer maximum. A very steep latitudinal gradient in water vapor abundance (high in the north) forms during early northern summer (Ls= 90o--150o), while water vapor is distributed more uniformly in latitude during early southern summer (Ls= 270o--330o). The annually-averaged amount of water vapor in the Martian atmosphere is 17 pr-μ m in the northern hemisphere and 9.5 pr-μ m in the southern hemisphere. However, when referenced to a 6.1 mbar pressure surface to remove the effect of topography, the annually-averaged amount of water vapor becomes 17 pr-μ m in the latitude band from 10oS--40oN, and 12 pr-μ m everywhere else. The latitude-longitude dependence of annually-averaged water vapor (corrected for topography) has a significant positive correlation with albedo and significant negative correlations with thermal inertia and surface pressure.

  17. Water Quality Trends in the Entiat River Subbasin: Final 2008 Annual Report.

    SciTech Connect

    Woodsmith, Richard; Bookter, Andy

    2009-03-30

    The ISEMP program monitors the status and trend of water quality elements that may affect restoration project effectiveness in the Entiat subbasin. As part of this effort, the PNW Research Station (PNW) measures, analyzes and interprets temporal trends in natural stream water pH, dissolved oxygen, specific conductivity and temperature. The Entiat River is currently on the Clean Water Act 303(d) list for pH exceedence, and there is insufficient information to determine the spatial and temporal extent or potential causes of this exceedence. In the spring 2008, PNW redeployed data-logging, multiparameter probes at four locations in the Entiat subbasin to measure water quality parameters, focusing on pH. This resumed previous data collection that was interrupted by river ice in early December 2007. Instruments were again removed from the river in early December 2008. This annual report covers the period from December 2007 through December 2008. The highest pH values occurred during the low-flow period from midsummer through the following midspring then dropped sharply during the annual snowmelt runoff period from late spring through early summer. Water temperature began rapidly increasing during the receding limb of the annual snowmelt hydrograph. Highest mean monthly temperatures occurred in July and August, while instantaneous maxima occurred during the period July-September. Dissolved oxygen reached its lowest levels during the period of highest water temperature in July-September. Specific conductivity remained very low at all sites throughout the year.

  18. Upper limits to the water abundance in starburst galaxies

    NASA Astrophysics Data System (ADS)

    Wilson, C. D.; Booth, R. S.; Olofsson, A. O. H.; Olberg, M.; Persson, C. M.; Sandqvist, Aa.; Hjalmarson, Â.; Buat, V.; Encrenaz, P. J.; Fich, M.; Frisk, U.; Gerin, M.; Rydback, G.; Wiklind, T.

    2007-07-01

    Aims:We have searched for emission from the 557 GHz ortho-water line in the interstellar medium of six nearby starburst galaxies. Methods: We used the Odin satellite to observe the 110{-}101 transition of o-H2O in the galaxies NGC 253, IC 342, M 82, NGC 4258, CenA, and M 51. None of the galaxies in our sample was detected. Results: We derive three sigma upper limits to the H2O abundance relative to H2 ranging from 2×10-9 to 1×10-8. The best of these upper limits are comparable to the measured abundance of H2O in the Galactic star forming region W3. However, if only 10% of the molecular gas is in very dense cores, then the water abundance limits in the cores themselves would be larger by a factor of 10 i.e. 2×10-8 to 1×10-7. Conclusions: These observations suggest that detections of H2O emission in galaxies with the upcoming Herschel Space Observatory are likely to require on-source integration times of an hour or more except in the very brightest extragalactic targets such as M 82 and NGC 253. Based on observations with Odin, a Swedish-led satellite project funded jointly by the Swedish National Space Board (SNSB), the Canadian Space Agency (CSA), the National Technology Agency of Finland (Tekes) and Centre National d'Etude Spatiale (CNES). The Swedish Space Corporation has been the industrial prime contractor and also is operating the satellite.

  19. Seaward Limit of Significant Sand Transport by Waves: An Annual Zonation for Seasonal Profiles.

    DTIC Science & Technology

    1981-01-01

    for significant profile changes (elevation excursions greater than ±0.5 foot or ±0.15 meter) throughout a yearly cycle of wave climate . Linear wave...NOTES 19. KEY WOR S (Continue on reverse side If neceeary end Identify by block number) Beach rofiles Coastal engineering Sand transport Wave climate ...and seaward bounds of the shoal zone, are calculated in Section II, using sand characteristics and statistics of annual wave climate for a given

  20. The Annual Cycle of Water Vapor on Mars as Observed by the Thermal Emission Spectrometer

    NASA Technical Reports Server (NTRS)

    Smith, Michael D.; Vondrak, Richard R. (Technical Monitor)

    2001-01-01

    Spectra taken by the Mars Global Surveyor Thermal Emission Spectrometer (TES) have been used to monitor the latitude, longitude, and seasonal dependence of water vapor for over one full Martian year (March 1999-March 2001). A maximum in water vapor abundance is observed at high latitudes during mid-summer in both hemispheres, reaching a maximum value of approximately 100 pr-micrometer in the north and approximately 50 pr-micrometer in the south. Low water vapor abundance (<5 pr-micrometer) is observed at middle and high latitudes in the fall and winter of both hemispheres. There are large differences in the hemispheric (north versus south) and seasonal (perihelion versus aphelion) behavior of water vapor. The latitudinal and seasonal dependence of the decay of the northern summer water vapor maximum implies cross-equatorial transport of water to the southern hemisphere, while there is little or no corresponding transport during the decay of the southern hemisphere summer maximum. The latitude-longitude dependence of annually-averaged water vapor (corrected for topography) has a significant positive correlation with albedo and significant negative correlations with thermal inertia and surface pressure. Comparison of TES results with those retrieved from the Viking Orbiter Mars Atmospheric Water Detectors (MAWD) experiments shows some similar features, but also many significant differences. The southern hemisphere maximum observed by TES was not observed by MAWD and the large latitudinal gradient in annually-averaged water vapor observed by MAWD does not appear in the TES results.

  1. Nutrient and water addition effects on day- and night-time conductance and transpiration in a C3 desert annual.

    PubMed

    Ludwig, Fulco; Jewitt, Rebecca A; Donovan, Lisa A

    2006-06-01

    Recent research has shown that many C3 plant species have significant stomatal opening and transpire water at night even in desert habitats. Day-time stomatal regulation is expected to maximize carbon gain and prevent runaway cavitation, but little is known about the effect of soil resource availability on night-time stomatal conductance (g) and transpiration (E). Water (low and high) and nutrients (low and high) were applied factorially during the growing season to naturally occurring seedlings of the annual Helianthus anomalus. Plant height and biomass were greatest in the treatment where both water and nutrients were added, confirming resource limitations in this habitat. Plants from all treatments showed significant night-time g (approximately 0.07 mol m(-2) s(-1)) and E (approximately 1.5 mol m(-2) s(-1)). In July, water and nutrient additions had few effects on day- or night-time gas exchange. In August, however, plants in the nutrient addition treatments had lower day-time photosynthesis, g and E, paralleled by lower night-time g and E. Lower predawn water potentials and higher integrated photosynthetic water-use efficiency suggests that the nutrient addition indirectly induced a mild water stress. Thus, soil resources can affect night-time g and E in a manner parallel to day-time, although additional factors may also be involved.

  2. Diffusion Limited Supercritical Water Oxidation (SCWO) in Microgravity Environments

    NASA Technical Reports Server (NTRS)

    Hicks, M. C.; Lauver, R. W.; Hegde, U. G.; Sikora, T. J.

    2006-01-01

    Tests designed to quantify the gravitational effects on thermal mixing and reactant injection in a Supercritical Water Oxidation (SCWO) reactor have recently been performed in the Zero Gravity Facility (ZGF) at NASA s Glenn Research Center. An artificial waste stream, comprising aqueous mixtures of methanol, was pressurized to approximately 250 atm and then heated to 450 C. After uniform temperatures in the reactor were verified, a controlled injection of air was initiated through a specially designed injector to simulate diffusion limited reactions typical in most continuous flow reactors. Results from a thermal mapping of the reaction zone in both 1-g and 0-g environments are compared. Additionally, results of a numerical model of the test configuration are presented to illustrate first order effects on reactant mixing and thermal transport in the absence of gravity.

  3. Kinetic Limited Water Evaporation in Hydrophilic Nanofluidic Channels

    NASA Astrophysics Data System (ADS)

    Li, Yinxiao; Alibakhshi, Mohammad Amin; Xie, Quan; Duan, Chuanhua

    2015-11-01

    Capillary evaporation is one of the most efficient approaches for heat and mass transfer, but the interfacial resistance in capillary evaporation governed by the kinetic theory has remained poorly understood. Here we report experimental studies of the kinetic-limited water capillary evaporation in 2-D hydrophilic nanochannels. A novel hybrid nanochannel design is employed to guarantee sufficient water supply to the liquid/vapor evaporation interface and to enable precise evaporation rate measurements. We study the effects of confinement (16 ~ 105nm), temperature (20 ~ 40 °C), and relative humidity (0% ~ 60%) on the evaporation rate and the evaporation coefficient. A maximum evaporation flux of 21287 micron/s is obtained in 16-nm nanochannels at 40°C and RH =0%, which corresponds to a heat flux of 4804 W/cm°. The evaporation coefficient is found to be independent on geometrical confinement, but shows a clear dependence on temperature, decreasing from 0.55 at 20°C to 0.5 at 40 °C. These findings have implications for understanding heat and mass transport in nanofluidic devices and porous media, and shed light on further development of evaporation-based technologies for thermal management, membrane purification and lab-on-a-chip devices. The work is supported by the American Chemical Society Petroleum Research Fund (ACS PRF # 54118-DNI7) and the Faculty Startup Fund (Boston University, USA).

  4. Flow Analysis on a Limited Volume Chilled Water System

    SciTech Connect

    Zheng, Lin

    2012-07-31

    LANL Currently has a limited volume chilled water system for use in a glove box, but the system needs to be updated. Before we start building our new system, a flow analysis is needed to ensure that there are no high flow rates, extreme pressures, or any other hazards involved in the system. In this project the piping system is extremely important to us because it directly affects the overall design of the entire system. The primary components necessary for the chilled water piping system are shown in the design. They include the pipes themselves (perhaps of more than one diameter), the various fitting used to connect the individual pipes to form the desired system, the flow rate control devices (valves), and the pumps that add energy to the fluid. Even the most simple pipe systems are actually quite complex when they are viewed in terms of rigorous analytical considerations. I used an 'exact' analysis and dimensional analysis considerations combined with experimental results for this project. When 'real-world' effects are important (such as viscous effects in pipe flows), it is often difficult or impossible to use only theoretical methods to obtain the desired results. A judicious combination of experimental data with theoretical considerations and dimensional analysis are needed in order to reduce risks to an acceptable level.

  5. 50 CFR Table 33 to Part 679 - Annual Apportion of Amendment 80 Species ITAC Between the Amendment 80 and BSAI Trawl Limited...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Annual Apportion of Amendment 80 Species ITAC Between the Amendment 80 and BSAI Trawl Limited Access Sectors (Except Yellowfin Sole) 33 Table 33... ALASKA Pt. 679, Table 33 Table 33 to Part 679— Annual Apportion of Amendment 80 Species ITAC Between...

  6. Nitrogen limited biobarriers remove atrazine from contaminated water: laboratory studies.

    PubMed

    Hunter, William J; Shaner, Dale L

    2009-01-07

    Atrazine is one of the most frequently used herbicides. This usage coupled with its mobility and recalcitrant nature in deeper soils and aquifers makes it a frequently encountered groundwater contaminant. We formed biobarriers in sand filled columns by coating the sand with soybean oil; after which, we inoculated the barriers with a consortium of atrazine-degrading microorganisms and evaluated the ability of the barriers to remove atrazine from a simulated groundwater containing 1 mg L(-1) atrazine. The soybean oil provided a carbon rich and nitrogen poor substrate to the microbial consortium. Under these nitrogen-limiting conditions it was hypothesized that bacteria capable of using atrazine as a source of nitrogen would remove atrazine from the flowing water. Our hypothesis proved correct and the biobarriers were effective at removing atrazine when the nitrogen content of the influent water was low. Levels of atrazine in the biobarrier effluents declined with time and by the 24th week of the study no detectable atrazine was present (limit of detection<0.005 mg L(-1)). Larger amounts of atrazine were also removed by the biobarriers; when biobarriers were fed 16.3 mg L(-1) atrazine 97% was degraded. When nitrate (5 mg L(-1) N), an alternate source of nitrogen, was added to the influent water the atrazine removal efficiency of the barriers was reduced by almost 60%. This result supports the hypothesis that atrazine was degraded as a source of nitrogen. Poisoning of the biobarriers with mercury chloride resulted in an immediate and large increase in the amount of atrazine in the barrier effluents confirming that biological activity and not abiotic factors were responsible for most of the atrazine degradation. The presence of hydroxyatrazine in the barrier effluents indicated that dehalogenation was one of the pathways of atrazine degradation. Permeable barriers might be formed in-situ by the injection of innocuous vegetable oil emulsions into an aquifer or sandy soil

  7. Recent trends in vegetation greenness in China significantly altered annual evapotranspiration and water yield

    NASA Astrophysics Data System (ADS)

    Liu, Yibo; Xiao, Jingfeng; Ju, Weimin; Xu, Ke; Zhou, Yanlian; Zhao, Yuntai

    2016-09-01

    There has been growing evidence that vegetation greenness has been increasing in many parts of the northern middle and high latitudes including China during the last three to four decades. However, the effects of increasing vegetation greenness particularly afforestation on the hydrological cycle have been controversial. We used a process-based ecosystem model and a satellite-derived leaf area index (LAI) dataset to examine how the changes in vegetation greenness affected annual evapotranspiration (ET) and water yield for China over the period from 2000 to 2014. Significant trends in vegetation greenness were observed in 26.1% of China’s land area. We used two model simulations driven with original and detrended LAI, respectively, to assess the effects of vegetation ‘greening’ and ‘browning’ on terrestrial ET and water yield. On a per-pixel basis, vegetation greening increased annual ET and decreased water yield, while vegetation browning reduced ET and increased water yield. At the large river basin and national scales, the greening trends also had positive effects on annual ET and had negative effects on water yield. Our results showed that the effects of the changes in vegetation greenness on the hydrological cycle varied with spatial scale. Afforestation efforts perhaps should focus on southern China with larger water supply given the water crisis in northern China and the negative effects of vegetation greening on water yield. Future studies on the effects of the greenness changes on the hydrological cycle are needed to account for the feedbacks to the climate.

  8. 40 CFR Appendix A to Part 72 - Methodology for Annualization of Emissions Limits

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Emissions Limits A Appendix A to Part 72 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Pt. 72, App. A Appendix A to Part 72—Methodology for... section 402(18) of the CAA. Many emission limits are enforced on a shorter term basis (or averaging...

  9. The dynamics of annual carbon allocation to wood in European forests is consistent with a combined source-sink limitation of growth.

    NASA Astrophysics Data System (ADS)

    Guillemot, Joannès; Martin-StPaul, Nicolas K.; Dufrêne, Eric; François, Christophe; Soudani, Kamel; Ourcival, Jean-Marc; Leadley, Paul; Delpierre, Nicolas

    2015-04-01

    The extent to which forest growth is limited by carbon (C) supply (source control) or by cambial activity (sink control) will strongly determines the responses of trees to global changes. However, the physiological processes responsible for the limitation of forest growth are still under debate. The aim of this study was i) to evaluate the key drivers of the annual carbon allocation to wood along large soil and climate regional gradients in four tree species representative of the main European forest biomes (Fagus sylvatica, Quercus petraea, Quercus ilex and Picea abies) ii) to implement the identified key drivers in a new C allocation scheme within the CASTANEA terrestrial biosphere model (TBM). Combining field measurements and process-based simulations at 49 sites (931 site-years), our analyses revealed that the inter-site variability in C allocation to wood was predominantly driven by an age-related decline. The direct control of temperature or water stress on sink activity (i.e. independently from their effects on C supply) exerted a strong influence on the annual woody growth in all the species considered, including deciduous temperate species. The lagged effect of the past environment conditions was a significant driver of the annual C allocation to wood. Carbon supply appeared to strongly limit growth only in deciduous temperate species. Our study supports the premise that European forest growth is under a complex panel of source- and sink- limitations, contradicting the simple source control implemented in most TBMs. The implementation of these combined forest growth limitations in the CASTANEA model significantly improved its performance when evaluated against independent stand growth data at the regional scale (mainland France, >10000 plots). We finally discuss how the sink imitation affects the CASTANEA simulated projections of forest productivity along the 21th century, especially with respect to the expected fertilizing effect of increasing atmospheric

  10. Sub-annual variability in historical water source use by Mediterranean riparian trees.

    NASA Astrophysics Data System (ADS)

    Sargeant, Christopher; Singer, Michael

    2016-04-01

    The seasonal availability of water within a tree's rooting zone may be an important determinant for individual tree growth and overall forest health, particularly in riparian corridors of Mediterranean climate zones that are vulnerable to water stress. Here, we present a new method that combines dendro-isotopes and isotope-modelling for determining how water source use varies over 10 consecutive growing seasons (2000-2010) for co-occurring species P. nigra and F. excelsior, along the Rhône River, south-eastern France. We conducted highly resolved cellulose δ18O analysis of micro-slices within tree rings and back-calculated the δ18O signature of source water available at the time of growth using a biochemical fractionation model. We related these patterns to inferred seasonal hydrological partitioning through comparison with δ18O of waters from the vadose and phreatic zones, precipitation, and streamflow. The shallowly rooted Fraxinus displayed greater sub-annual source water variability, as well as greater isotopic enrichment, reflecting use of precipitation-derived vadose moisture. Its earlywood component was formed mainly from winter rainfall (depleted) whilst the latewood relied on growing season precipitation (enriched). In Populus, the sub-annual source water use was relatively depleted, suggesting use of hyporheic water and regional groundwater. From 2007, both species converged in their pattern of water source uptake which was attributed to a decline in phreatic water access for Populus. These results demonstrate that the seasonal variability in source water use can be identified retrospectively, a method which may prove important for anticipating the future consequences of climatic driven changes to the hydrological cycle.

  11. 12 CFR 226.55 - Limitations on increasing annual percentage rates, fees, and charges.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Special Rules Applicable to Credit Card Accounts and Open-End Credit Offered to College Students § 226.55 Limitations...

  12. 12 CFR 226.55 - Limitations on increasing annual percentage rates, fees, and charges.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Special Rules Applicable to Credit Card Accounts and Open-End Credit Offered to College Students § 226.55 Limitations...

  13. Optimal crop selection and water allocation under limited water supply in irrigation

    NASA Astrophysics Data System (ADS)

    Stange, Peter; Grießbach, Ulrike; Schütze, Niels

    2015-04-01

    Due to climate change, extreme weather conditions such as droughts may have an increasing impact on irrigated agriculture. To cope with limited water resources in irrigation systems, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand at the same time. For modeling the regional water demand, local (and site-specific) water demand functions are used which are derived from optimized agronomic response on farms scale. To account for climate variability the agronomic response is represented by stochastic crop water production functions (SCWPF). These functions take into account different soil types, crops and stochastically generated climate scenarios. The SCWPF's are used to compute the water demand considering different conditions, e.g., variable and fixed costs. This generic approach enables the consideration of both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance IRrigation) project a prototype of a decision support system is developed which helps to evaluate combined water supply and demand management policies.

  14. Does leaf water efficiency vary among eucalypts in water-limited environments?

    PubMed

    Hatton, Tom; Reece, Peter; Taylor, Peter; McEwan, Kerryn

    1998-01-01

    There is a need to generalize water use behavior of eucalypts to facilitate bioengineering and landscape remediation programs in a wide range of Australian environments. A critical question can be stated as a null hypothesis: tree water use per unit leaf area (leaf efficiency) is independent of eucalypt species. This is implicitly equivalent to the hydrological equilibrium hypothesis that states that leaf area is a function of climate, at least in cases where transpiration and growth are limited by soil water. Failure to reject this null hypothesis simplifies (a) the selection of tree species for water balance management, (b) the generation of regional-scale expectations of leaf area index, and (c) the estimation (monitoring) of the effectiveness of plantations in controlling site water balance. The hypothesis was tested with tree water use data collected in natural multi-species stands across Australia, including sites in the wet-dry season tropical woodlands of the Northern Territory, the Mediterranean climate forests of Western Australia, and a woodland system in southern New South Wales receiving an even distribution of rainfall throughout the year. We also tested the hypothesis in a multi-species tree plantation growing on a saline gradient. In each case, we could not reject the hypothesis of constant leaf efficiency among eucalypts. In every case there was a common, strong, linear relationship among tree leaf area and mean daily water use by all tree species in a sample. Single factor (species) analysis of variance did not detect significant differences between leaf water efficiencies of species. For the jarrah forest (Eucalyptus marginata J. Donn ex Sm., E. calophylla R. Br. ex Lindl.), the null hypothesis held in both spring (wet) and autumn (dry) conditions. The null hypothesis held in the mixed species woodland of New South Wales (E. macrorhynca F.J. Muell. ex Benth., E. blakelyi Maiden., E. polyanthemos Schauer.) under summer and autumn conditions, and

  15. Annual summary of ground-water conditions in Arizona, spring 1984 to spring 1985

    USGS Publications Warehouse

    ,

    1986-01-01

    In arid and semiarid regions such as Arizona, the availability of adequate water supplies has a significant influence on the type and extent of economic development. About two-thirds of the water used in the State is groundwater. The nature and extent of the groundwater reservoirs must be known for proper management of this valuable resource. The U.S. Geological Survey, in cooperation with the State of Arizona, has conducted a program of groundwater studies in Arizona since 1939. The primary purposes of these studies are to define the amount, location, and quality of the groundwater resources of Arizona and to monitor the effects of large-scale development of the groundwater supplies. The program includes the collection, compilation, and analysis of the geologic and hydrologic data necessary to evaluate the groundwater resources of the State. The basic hydrologic data are in computer storage and are available to the public. Since 1974, a major thrust of the program has been to inventory the groundwater conditions in the 68 groundwater areas of the State. Several selected groundwater areas are studied each year; water levels are measured annually in a statewide observation well network, many groundwater samples are collected and analyzed annually, and groundwater pumpage is computed for most of the areas. As of July 1985, reports had been published for 56 of the 68 groundwater areas. Data collected in the groundwater areas include information on selected wells, water level measurements, and water samples for chemical analysis. The data for each of the selected groundwater areas are analyzed, and the results are published in map form. Typically, the maps show depth to water; change in water levels; altitude of the water level; and quality of water data, such as specific conductance, dissolved solids, and fluoride. (Lantz-PTT)

  16. A review of permissible limits of drinking water.

    PubMed

    Kumar, Manoj; Puri, Avinash

    2012-01-01

    Water is one of the prime necessities of life. We can hardly live for a few days without water. In a man's body, 70-80% is water. Cell, blood, and bones contain 90%, 75%, and 22% water, respectively. The general survey reveals that the total surface area of earth is 51 crore km(2) out of which 36.1 crore km(2) is covered sea. In addition to this, we get water from rivers, lakes, tanks, and now on hills. In spite of such abundance, there is a shortage of soft water in the world. Physicochemical parameter of any water body plays a very important role in maintaining the fragile ecosystem that maintains various life forms. Present research paper deals with various water quality parameter, chlorides, dissolved oxygen, total iron, nitrate, water temperature, pH, total phosphorous, fecal coli form bacteria, and adverse effect of these parameters on human being.

  17. Life history traits in selfing versus outcrossing annuals: exploring the 'time-limitation' hypothesis for the fitness benefit of self-pollination

    PubMed Central

    Snell, Rebecca; Aarssen, Lonnie W

    2005-01-01

    Background Most self-pollinating plants are annuals. According to the 'time-limitation' hypothesis, this association between selfing and the annual life cycle has evolved as a consequence of strong r-selection, involving severe time-limitation for completing the life cycle. Under this model, selection from frequent density-independent mortality in ephemeral habitats minimizes time to flower maturation, with selfing as a trade-off, and / or selection minimizes the time between flower maturation and ovule fertilization, in which case selfing has a direct fitness benefit. Predictions arising from this hypothesis were evaluated using phylogenetically-independent contrasts of several life history traits in predominantly selfing versus outcrossing annuals from a data base of 118 species distributed across 14 families. Data for life history traits specifically related to maturation and pollination times were obtained by monitoring the start and completion of different stages of reproductive development in a greenhouse study of selfing and outcrossing annuals from an unbiased sample of 25 species involving five pair-wise family comparisons and four pair-wise genus comparisons. Results Selfing annuals in general had significantly shorter plant heights, smaller flowers, shorter bud development times, shorter flower longevity and smaller seed sizes compared with their outcrossing annual relatives. Age at first flower did not differ significantly between selfing and outcrossing annuals. Conclusions This is the first multi-species study to report these general life-history differences between selfers and outcrossers among annuals exclusively. The results are all explained more parsimoniously by selection associated with time-limitation than by selection associated with pollinator/mate limitation. The shorter bud development time reported here for selfing annuals is predicted explicitly by the time-limitation hypothesis for the fitness benefit of selfing (and not by the

  18. The annual cycle of stratospheric water vapor in a general circulation model

    NASA Technical Reports Server (NTRS)

    Mote, Philip W.

    1995-01-01

    The application of general circulation models (GCM's) to stratospheric chemistry and transport both permits and requires a thorough investigation of stratospheric water vapor. The National Center for Atmospheric Research has redesigned its GCM, the Community Climate Model (CCM2), to enable studies of the chemistry and transport of tracers including water vapor; the importance of water vapor to the climate and chemistry of the stratosphere requires that it be better understood in the atmosphere and well represented in the model. In this study, methane is carried as a tracer and converted to water; this simple chemistry provides an adequate representation of the upper stratospheric water vapor source. The cold temperature bias in the winter polar stratosphere, which the CCM2 shares with other GCM's, produces excessive dehydration in the southern hemisphere, but this dry bias can be ameliorated by setting a minimum vapor pressure. The CCM2's water vapor distribution and seasonality compare favorably with observations in many respects, though seasonal variations including the upper stratospheric semiannual oscillation are generally too small. Southern polar dehydration affects midlatitude water vapor mixing ratios by a few tenths of a part per million, mostly after the demise of the vortex. The annual cycle of water vapor in the tropical and northern midlatitude lower stratosphere is dominated by drying at the tropical tropopause. Water vapor has a longer adjustment time than methane and had not reached equilibrium at the end of the 9 years simulated here.

  19. Evaluation of intra-annual variation in U.S. Geological Survey National Water Quality Assessment ground water quality data.

    PubMed

    Rosen, Michael R; Voss, Frank D; Arufe, Jorge A

    2008-01-01

    Assessment of ground-water quality trends under the U.S. Geological Survey National Water-Quality Assessment Program (NAWQA) included the analysis of samples collected on a quarterly basis for 1 yr between 2001 and 2005. The purpose of this quarterly sampling was to test the hypothesis that variations in the concentration of water-quality parameters of selected individual wells could demonstrate that the intra-annual variation was greater or less than the decadal changes observed for a trend network. Evaluation of more than 100 wells over this period indicates that 1 yr of quarterly sampling is not adequate to address the issue of intra-annual variation because variations seem to be random and highly variable between different wells in the same networks and among networks located in different geographical areas of the USA. In addition, the data from only 1 yr makes it impossible to assess whether variations are due to univariate changes caused by land use changes, hydrologic variations due to variable recharge, or variations caused by ground-water pumping. These data indicate that funds allocated to this activity can be directed to the collection of more effective trend data, including age dating of all wells in the NAWQA network using multiple techniques. Continued evaluation of data and updating of monitoring plans of the NAWQA program is important for maintaining relevance to national goals and scientific objectives.

  20. 38 CFR 3.26 - Section 306 and old-law pension annual income limitations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... L. 95-588, as increased from time to time under section 306(b)(4) of Pub. L. 95-588. (d) Each time there is an increase under section 306 (a)(3) or (b)(4) of Pub. L. 95-588, the actual income limitations... from time to time under section 306(a)(3) of Pub. L. 95-588. (b) If a beneficiary under section...

  1. Irrigation in water restricted regions: Managing water use efficiency with limited available water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Political and social pressures to increase water-use efficiency in agriculture from plant to regional scales are reaching critical levels. A region where these pressures have been extremely acute is most semi-arid parts of Texas where reliable crop production is possible only through irrigation. Re...

  2. 1995 annual water monitoring report, LEHR environmental restoration, University of California at Davis

    SciTech Connect

    Stewart, D.L.; Smith, R.M.; Sauer, D.R.

    1996-03-01

    This 1995 Annual Water Monitoring Report presents analytical data collected between January and December 1995 at the Laboratory for Energy-Related Health Research (LEHR) located at the University of California (UC), Davis. This report has been prepared by Pacific Northwest National Laboratory in compliance with the Water Monitoring Plan for the LEHR site, which contains the sample collection, analysis, and quality assurance/quality control procedures and reporting requirements. Water monitoring during 1995 was conducted in conjunction with the Remedial Investigation/Feasibility Study currently being implemented at the LEHR site as part of a US Department of Energy (DOE)-sponsored environmental restoration program. Based on a review of historical groundwater monitoring data compiled since the fall of 1990, the list of analytes included in the program was reduced and the schedule for analyzing the remaining analytes was revised. The revision was implemented for the first time in the summer monitoring period. Analytes eliminated from the program were those that were (1) important for establishing baseline groundwater chemistry (alkalinity, anions, Eh, total organic carbon, and chemical oxygen demand); (2) important for establishing sources of contamination; (3) not detected in water samples or not from the LEHR site; and (4) duplicates of another measurement. Reductions in the analytical schedule were based on the monitoring history for each well; the resultant constituents of concern list was developed for individual wells. Depending on its importance in a well, each analyte was analyzed quarterly, semi-annually, or annually. Pollutants of major concern include organic compounds, metals, and radionuclides.

  3. Upscaling of annual mean and dynamics of water table depth in German organic soils

    NASA Astrophysics Data System (ADS)

    Bechtold, Michel; Tiemeyer, Bärbel; Belting, Susanne; Laggner, Andreas; Leppelt, Thomas; Frahm, Enrico; Freibauer, Annette

    2013-04-01

    Water table depth is the key parameter controlling the fluxes of CO2, CH4 and N2O from organic soils (peatlands and other organic soils). Therefore, a good estimation of the spatial distribution of water table depth is crucial in any upscaling approach for these greenhouse gases (GHGs). It is further the prerequisite to assess the effects of re-wetting measures. There are attempts to obtain maps of water table depth at large scales (e.g. national or continental) by using process-based hydrological model concepts. However, major problem of the process-based approach is the representation of the water management (ditches, tile drains, pumping and weir management), which is at the best known spatially just for the ditch patterns. Thus, this approach is hardly applicable to the diversely-drained and -used organic soils in central Europe. Here, we present an alternative, data-driven approach for upscaling annual mean and dynamics of water table depth in organic soils. Groundwater level data of a unique dataset from about 60 peatlands, 1100 dipwells and around 8000 annual data sets, is the basis of this approach. Time series were used to calculate long-term annual means, average annual amplitudes and ponding durations. In case of continuous observations, shape parameters of the annual frequency distribution of water table depths were calculated. For each well, numerous site characteristics were collected as possible explanatory variables. This collection was restricted to nationally-available data. For each dipwell, land use is taken from official land use maps (German database ATKIS), and the soil type from the national geological map (1:200.000). In case of reliable site information, maps were corrected accordingly. Additionally, from these maps, topological indicators such as the ditch distance and density, the distance to the edge of the peatland and the peatland area within different buffers were calculated. Meteorological data (precipitation, potential

  4. Derivation and implementation of an annual limit on intake and a derived air concentration value for uranium mill tailings.

    PubMed

    Reif, R H; Andrews, D W

    1995-06-01

    Monitoring workers and work areas at the Department of Energy Uranium Mill Tailings Remedial Action Project sites is complex because all radionuclides in the 238U and 235U decay chains may be present in an airborne uranium mill tailings matrix. Previous monitoring practices involved isotopic analysis of the air filter to determine the activity of each radionuclide of concern and comparing the results to the specified derived air concentration. The annual limit on intake and derived air concentration values have been derived here for the uranium mill tailings matrix to simplify the procedure for evaluation of air monitoring results and assessment of the need for individual monitoring. Implementation of the derived air concentration for uranium mill tailings involves analyzing air samples for long-lived gross alpha activity and comparing the activity concentration to the derived air concentration. Health physics decisions regarding assessment of airborne concentrations is more cost-effective because isotopic analysis of air samples is not necessary.

  5. Evaluate Factors Limiting Columbia River Gorge Chum Salmon Populations : FY2001 Annual Report.

    SciTech Connect

    Hoffman, Thomas A.

    2001-12-01

    Juvenile and adult chum salmon were monitored in fiscal year 2001 to continue evaluating factors limiting production. Total adult salmon caught (in weirs or by carcass surveys) in Hardy Creek and Hamilton Springs in 2000 was 25 and 130 fish, respectively. Fifty-two fish captured in the main stem Columbia River, Hamilton Springs, Hardy Creek, or Bonneville Dam were implanted with radio tags and tracked with an array of fixed aerials and underwater antennae. Males tended to move greater distances than females. Population estimates in Hardy Creek and Hamilton Springs were 37{+-}2 and 157{+-}5, respectively. Chum smolt emigration began in Hamilton Springs 25 February 2001 and 2 March 2001 in Hardy Creek. Total catches in Hardy Creek and Hamilton Springs were 2,955 and 14,967, respectively. Population abundance estimates were 11,586{+-}1,836 in Hardy Creek and 84,520{+-}9,283 in Hamilton Springs.

  6. Water worlds: characterization, thermal evolution and habitability limitations

    NASA Astrophysics Data System (ADS)

    Noack, Lena; Heistracher, Clemens; Zimov, Nastasia; Hoening, Dennis; Rivoldini, Attilio; Van Hoolst, Tim; Lammer, Helmut; Hendrik Bredehoeft, Jan

    2015-04-01

    Water is necessary for the origin and survival of life like we know it. In the search for life-friendly worlds, water-rich planets therefore seem to be obvious candidates and have attracted increasing attention in the past years. The water layer on such planets could be hundreds of kilometers deep depending on the water content and the evolution of the proto-atmosphere. A deep water layer will likely form high-pressure ice from a specific depth on. We study possible constraints for the habitability of deep water layers and introduce a new habitability classification to be applied to water-rich planets (from about Mars-size to almost Neptune-size planets). A new ocean model has been developed coupled with an interior structure model to infer the depth-dependent thermodynamic properties of high-pressure water and the possible formation of high-pressure ice. We find that the ice layer can be molten from beneath by heat flowing out of the silicate mantle [Noack et al., in review, "Water worlds: how life-friendly is an ocean deeper than on Earth?"], depending amongst others on the thickness of the ocean-ice shell and the mass of the planet. From our results we conclude that water-rich planets with a deep ocean, a large planet mass, a high average density or a small surface temperature are less habitable than a planet with an Earth-like ocean and might not be suitable candidates for the origin of life. Ocean planets, that can be clearly detected as such, contain a large amount of water (to significantly reduce the average density of the planet) and are likely to have a thick high-pressure ice layer which cannot be molten from beneath - these planets might therefore not be habitable.

  7. Inter- annual variability of water vapor over an equatorial coastal station using Microwave Radiometer observations.

    NASA Astrophysics Data System (ADS)

    Renju, Ramachandran Pillai; Uma, K. N.; Krishna Moorthy, K.; Mathew, Nizy; Raju C, Suresh

    The south-western region of the Indian peninsula is the gateway of Indian summer monsoon. This region experiences continuous monsoon rain for a longer period of about six months from June to November. The amount of water vapor variability is one of the important parameters to study the onset, active and break phases of the monsoon. Keeping this in view, a multi-frequency Microwave Radiometer Profiler (MRP) has been made operational for continuous measurements of water vapor over an equatorial coastal station Thiruvananthapuram (8.5(°) N, 76.9(°) E) since April 2010. The MRP estimated precipitable water vapor (PWV) for different seasons including monsoon periods have been evaluated by comparing with the collocated GPS derived water vapor and radiosonde measurements. The diurnal, seasonal and inter annual variation of water vapor has been studied for the last four years (2010-2013) over this station. The significant diurnal variability of water vapor is found only during the winter and pre-monsoon periods (Dec -April). The vertical distribution of water vapour is studied in order to understand its variability especially during the onset of monsoon. During the building up of south-west monsoon, the specific humidity increases to ˜ 10g/kg in the altitude range of 4-6 km and consistently maintained it throughout the active spells and reduces to below 2g/kg during break spells of monsoon. The instrument details and the results will be presented.

  8. STORM WATER BEST MANAGEMENT PRACTICES: CAPACITIES, CAPABILITIES, AND SOME LIMITATIONS

    EPA Science Inventory

    This presentation will cover the basics of what a storm water best management practices and focus on infiltration-type practices using the example of rain gardens. I will demonstrate how water moves through rain gardens with a simple hydrologic model and discuss ancillary benefit...

  9. Generalized estimates from streamflow data of annual and seasonal ground-water-recharge rates for drainage basins in New Hampshire

    USGS Publications Warehouse

    Flynn, Robert H.; Tasker, Gary D.

    2004-01-01

    This report presents regression equations to estimate generalized annual and seasonal ground-water-recharge rates in drainage basins in New Hampshire. The ultimate source of water for a ground-water withdrawal is aquifer recharge from a combination of precipitation on the aquifer, ground-water flow from upland basin areas, and infiltration from streambeds to the aquifer. An assessment of ground-water availability in a basin requires that recharge rates be estimated under `normal' conditions and under assumed drought conditions. Recharge equations were developed by analyzing streamflow, basin characteristics, and precipitation at 55 unregulated continuous record stream-gaging stations in New Hampshire and in adjacent states. In the initial step, streamflow records were analyzed to estimate a series of annual and seasonal ground-water-recharge components of streamflow in each drainage basin evaluated in this study. Regression equations were then developed relating the series of annual and seasonal ground-water-recharge values to the corresponding series of annual and seasonal precipitation values as determined at the centroid of each drainage basin. This resulted in one equation for each of the 55 basins for each of the four seasonal periods and the annual period, or a total of 275 regression equations. Average annual and seasonal precipitation data for 1961-90 were then used to compute a set of normalized ground-water-recharge values that reflected the long-term average annual and seasonal variations (normalized) and mean recharge characteristics of each drainage basin. Ordinary-least-squares regression was applied in the process of selecting 10 out of 93 possible basin and climatic characteristics for further testing in the development of the equations for computing the generalized estimate of annual and seasonal ground-water recharge based on the set of normalized recharge values. Generalized-least-squares regression was used for the final parameter estimation and

  10. Evaluate Factors Limiting Columbia River Gorge Chum Salmon Populations; FY 2002 Annual Report.

    SciTech Connect

    Uusitalo, Nancy M.

    2003-01-30

    Adult and juvenile chum salmon were monitored from October 2001 through September 2002 to evaluate factors limiting production. In 2001, 6 and 69 adult chum salmon were captured in the Hardy Creek and Hamilton Springs weirs, respectively. In 2001, 285 and 328 chum salmon carcasses were recovered during spawning ground surveys in Hardy Creek and Hamilton Springs, respectively. Twenty-eight fish captured in the mainstem Columbia River, Hamilton Springs, and Hardy Creek were implanted with radio tags and tracked via an array of fixed aerial, underwater antennas and a mobile tracking unit. Using the Area-Under-the-Curve program population estimates of adult chum salmon were 835 in Hardy Creek and 617 in Hamilton Springs. Juvenile chum salmon migration was monitored from March-June 2002. Total catches for Hardy Creek and Hamilton Springs were 103,315 and 140,220, respectively. Estimates of juvenile chum salmon emigration were 450,195 ({+-}21,793) in Hardy Creek and 561,462 ({+-}21,423) in Hamilton Springs.

  11. Inter-annual precipitation fluctuations alter the responses of above- and belowground biomass to water and N enrichment

    NASA Astrophysics Data System (ADS)

    Kong, D. L.; Lü, X. T.; Jiang, L. L.; Wu, H. F.; Miao, Y.; Kardol, P.

    2013-08-01

    Water availability has profound effects on plant growth and productivity in temperate and semi-arid grasslands. However, it remains unclear how variation of inter-annual precipitation by extreme rainfall events will alter the aboveground and belowground responses of plants, and how these responses may be contingent on N availability. In this study, we examined the interactive effects of inter-annual precipitation variation and N addition on aboveground and live fine root biomass of a semi-arid grassland in northern China for two consecutive years (2007 and 2008). Inter-annual variation in precipitation resulting mainly from the occurrence of extreme rainfall events in 2008 significantly affected above- and belowground plant biomass responses to water addition. In addition, variation of inter-annual precipitation by this extreme rainfall event suppressed plant responses to nitrogen addition and reduced the interaction effects between water and nitrogen addition. These effects of inter-annual precipitation fluctuation could be attributed to the negative influence of the extreme rainfall event on soil N and water availability, ultimately reducing plant rainfall use efficiency and nitrogen use efficiency. In conclusion, our results suggest ecosystem responses to water and N enrichment could be altered by inter-annual variation of precipitation regime caused by the naturally occurring extreme rainfall events.

  12. 29 CFR 2520.103-12 - Limited exemption and alternative method of compliance for annual reporting of investments in...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... annual reporting of investments in certain entities. 2520.103-12 Section 2520.103-12 Labor Regulations... for annual reporting of investments in certain entities. (a) This section prescribes an exemption from and alternative method of compliance with the annual reporting requirements of part 1 of title I...

  13. Floatabilities of treated coal in water at room temperature. Annual topical report, September 1992--August 1993

    SciTech Connect

    Kwon, K.C.; Rohrer, R.L.; Lai, R.W.; Finseth, D.H.

    1993-12-31

    This report contains a research paper entitled ``Floatability of Treated Coal in Water at Room Temperature.`` Experimental data on equilibrium adsorption loadings of probe compounds on coal, and flotation of raw coals as well as treated coal were obtained, using Illinois No. 6 coal (PSOC-1539), Adaville No. 1 coal (PSOC-1544), Wyodak coal (PSOC-1545) and Pittsburgh No. 8 coal (PSOC-1549). The raw data of this Annual Topical Report are also available in the Quarterly Progress Report for the period April--June 1993 and the Quarterly Progress Report July--September 1993.

  14. Plastic Response of Tracheids in Pinus pinaster in a Water-Limited Environment: Adjusting Lumen Size instead of Wall Thickness

    PubMed Central

    Carvalho, Ana; Nabais, Cristina; Vieira, Joana; Rossi, Sergio; Campelo, Filipe

    2015-01-01

    The formation of wood results from cambial activity and its anatomical properties reflect the variability of environmental conditions during the growing season. Recently, it was found that wood density variations in conifers growing under cold-limited environment result from the adjustment of cell wall thickness (CWT) to temperature. Additionally, it is known that intra-annual density fluctuations (IADFs) are formed in response to precipitation after the summer drought. Although IADFs are frequent in Mediterranean conifers no study has yet been conducted to determine if these structures result from the adjustment of lumen diameter (LD) or CWT to soil water availability. Our main objective is to investigate the intra-ring variation of wood anatomical features (LD and CWT) in Pinus pinaster Ait. growing under a water-limited environment. We compared the tracheidograms of LD and CWT for the years 2010–2013 in P. pinaster growing in the west coast of Portugal. Our results suggest a close association between LD and soil moisture content along the growing season, reinforcing the role of water availability in determining tracheid size. Compared with CWT, LD showed a higher intra- and inter-annual variability suggesting its strong adjustment value to variations in water availability. The formation of a latewood IADF appears to be predisposed by higher rates of cell production in spring and triggered by early autumn precipitation. Our findings reinforce the crucial role of water availability on cambial activity and wood formation in Mediterranean conifers, and emphasize the high plasticity of wood anatomical features under Mediterranean climate. PMID:26305893

  15. Plastic Response of Tracheids in Pinus pinaster in a Water-Limited Environment: Adjusting Lumen Size instead of Wall Thickness.

    PubMed

    Carvalho, Ana; Nabais, Cristina; Vieira, Joana; Rossi, Sergio; Campelo, Filipe

    2015-01-01

    The formation of wood results from cambial activity and its anatomical properties reflect the variability of environmental conditions during the growing season. Recently, it was found that wood density variations in conifers growing under cold-limited environment result from the adjustment of cell wall thickness (CWT) to temperature. Additionally, it is known that intra-annual density fluctuations (IADFs) are formed in response to precipitation after the summer drought. Although IADFs are frequent in Mediterranean conifers no study has yet been conducted to determine if these structures result from the adjustment of lumen diameter (LD) or CWT to soil water availability. Our main objective is to investigate the intra-ring variation of wood anatomical features (LD and CWT) in Pinus pinaster Ait. growing under a water-limited environment. We compared the tracheidograms of LD and CWT for the years 2010-2013 in P. pinaster growing in the west coast of Portugal. Our results suggest a close association between LD and soil moisture content along the growing season, reinforcing the role of water availability in determining tracheid size. Compared with CWT, LD showed a higher intra- and inter-annual variability suggesting its strong adjustment value to variations in water availability. The formation of a latewood IADF appears to be predisposed by higher rates of cell production in spring and triggered by early autumn precipitation. Our findings reinforce the crucial role of water availability on cambial activity and wood formation in Mediterranean conifers, and emphasize the high plasticity of wood anatomical features under Mediterranean climate.

  16. Limiting shear stress and monotonic properties of liquid water

    NASA Astrophysics Data System (ADS)

    Gorshkov, A. I.

    2016-12-01

    Publications in scientific journals in which the authors attempt to experimentally prove that water, the most widespread substance on the Earth, is not a completely classical liquid, have become more frequent recently. This means, first, that water behaves as a solid at very low shear stress, i.e., does not flow, and, second, that the temperature dependences of its different properties are non-monotonic, i.e., possess singularities. We are aware of several such publications [1-5].

  17. Estimation of mean annual effective dose through radon concentration in the water and indoor air of Islamabad and Murree.

    PubMed

    Ali, N; Khan, E U; Akhter, P; Khan, F; Waheed, A

    2010-09-01

    Different samples of water, indoor air and soil gas have been collected from Islamabad (33 degrees 38'N, 73 degrees 09'E, altitude of 1760 ft.), the capital of Pakistan and Murree (33 degrees 53'N, 73 degrees 23'E, altitude of 7323 ft.), lying on a geological fault line and are analysed for the estimation of mean effective dose through radon concentrations by using RAD-7, a solid state alpha-detector. The variation of radon concentration in water, indoor air and soil gas in Islamabad region ranges from 25.90-158.40 kBq m(-3), 43.26-97.04 Bq m(-3) and 17.34-72.52 kBq m(-3), having mean values 88.63 kBq m(-3), 70.67 Bq m(-3) and 45.08 kBq m(-3)(,) respectively. It ranges from 1.64-10.20 kBq m(-3), 18.48-42.08 Bq m(-3) and 0.61-3.89 kBq m(-3) with mean values 4.38 kBq m(-3), 28.63 Bq m(-3) and 1.70 kBq m(-3)(,) respectively in Murree and its surroundings. The total mean annual effective doses from water and indoor air of Islamabad and Murree regions are 2.023 and 0.733 mSv a(-1), respectively. These doses are within the recommended limits of the world organisations.

  18. Limitation of hardness from thermal water by means of nanofiltration.

    PubMed

    Tonko, Csilla Maria; Kiraly, Andras; Mizsey, Peter; Patzay, Gyorgy; Csefalvay, Edit

    2013-01-01

    Geothermal conditions are extremely favourable in Hungary. Thermal water is accessible in 70% of the territory of the country, with a lowest temperature of 30°C. For energetic purposes, it can be utilized in two different ways: for supplying heat or generating electricity. In relation to utilization, one of the most serious problems derives from the chemical composition of thermal water. The present paper investigates the opportunities of preventing scaling by nanofiltration. Experiments were performed on a Thin Film NF DK membrane, thermostated at 50°C and at a pressure of 3.5 MPa with four different samples (from four Hungarian cities - Eger, Mezőkövesd, Bogács, Miskolc-Tapolca) using batch plant. Reproducibility of experiments was also investigated using water samples from Komárom at 50 and 60°C. The results showed that NF DK could achieve high retention of divalent ions. The results of the second phase of the experiments proved that water flux and rejections were very stable. After filtration, the scaling properties of thermal water were simulated with the help of chemical equilibrium modelling software, called Visual MINTEQ 3.0. The results of the permeate samples prove that nanofiltration is a successful process in preventing scaling of thermal water for further use.

  19. Limiter

    DOEpatents

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.

    1984-10-19

    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  20. Relating biomass and vegetation structure in water limited ecosystems using a celluar automata based model

    NASA Astrophysics Data System (ADS)

    Frechen, Nanu; Hinz, Christoph; McGrath, Gavan

    2015-04-01

    Within arid and semiarid regions banded vegetation patterns are wide spread. While the soil-vegetation feedback causing this self-organized has been well understood and implemented in various models, the relationship between the actual pattern, e.g. band width and spacing as well as plant density, has not been well understood. In this study we use a cellular automaton [1] to investigate the effect of infiltration properties and rainfall on patter formation as well as on biomass production and vegetation coverage. The first part of the investigation showed that the model is consistent with the existing knowledge on the dependence of wavelength on annual rainfall. We use the same parameter space to assess biomass and fractional coverage. We found that there is a nonlinear relationship between biomass and infiltration capacity normalized with rainfall input. This indicates that the degree of organisation is not directly related to the productivity as expressed with biomass. Similar results were found for fractional surface cover of the vegetation. [1] McGrath, G. S., K. Paik, and C. Hinz. 2012. Microtopography alters self-organized vegetation patterns in water-limited ecosystems, Journal of Geophysical Research: Biogeosciences (2005-2012) 117, G03021, doi:10.1029/2011JG001870

  1. Columbia Basin Water Transactions Program (Water Entity); National Fish and Wildlife Foundation, Annual Report 2003.

    SciTech Connect

    National Fish and Wildlife Foundation

    2004-02-01

    Launched in 2002, the Columbia Basin Water Transactions Program (CBWTP) is anticipated to be a five-year effort to test new strategies for enhancing tributary flows. The premise of the CBWTP is that water can most readily be made available for instream flows not by attempting to regulate senior water users but, instead, by acquiring water rights from willing sellers and transferring those rights to instream flows within the prior appropriation framework ('first in time, first in right'). The primary goals for this water initiative included: (1) To implement Action 151 of the NOAA Fisheries 2000 Biological Opinion on the Operation of the Federal Columbia River Power System. (2) To implement Provision A.8 of the Council's 2000 Columbia River Basin Fish and Wildlife Program related to securing water for instream flows. (3) To integrate components of the Northwest Power and Conservation Council's Program and Watershed Assessment process with the NOAA Fisheries 2000 Biological Opinion. (4) To ensure actions taken under the program would be effective, fiscally efficient, and biologically beneficial to fish and wildlife in the region. In the spring of 2002, BPA and a group of water experts selected ten local entities in Washington, Oregon, Idaho, and western Montana with a demonstrated potential to innovate and implement tributary flow improvements. We also selected the National Fish and Wildlife Foundation (NFWF) to serve as the regional entity for this initiative. BPA then set up the funding agreement and scope of work to establish what is now known as the Columbia Basin Water Transactions Program. In FY 2003, BPA provided over $1.5 million in funding to the CBWTP and approved 33 water transactions. In FY 2004, BPA will provide up to $4 million to the project to enhance habitat. Thanks to the dedicated efforts of partners throughout the Basin, the CBWTP is off to a strong start in improving tributary flows in key areas across the region.

  2. The Role of Vegetation Dynamics on the Soil Water Balance in Water-Limited Ecosystems

    NASA Astrophysics Data System (ADS)

    Montaldo, N.; Rondena, R.; Albertson, J. D.; Mancini, M.

    2003-12-01

    The structure and function of the vegetation regulates the exchange of mass, energy and momentum across the biosphere-atmosphere interface. Vegetation dynamics are usually neglected, other than seasonal phenology, in land surface models (LSMs). However, changes in vegetation densities, influencing the partitioning of incoming solar energy into sensible and latent heat fluxes, can result in long-term changes in both local and global climates (e.g., precipitation and temperature), which in turn will feedback to affect the vegetation growth. In semi-arid regions, this may result in persistent drought and desertification, with substantial impacts on the human populations of these regions through reduction in agricultural productivity and reduction in quantity and quality of water supply. With an objective of finding a simple vegetation model able to accurately simulate the leaf area index (LAI) dynamics, vegetation models of different level of complexity (e.g., including or not the modeling of the root biomass or the modeling of the dead biomass) are developed and compared. The vegetation dynamics models are coupled to a LSM, with the vegetation models providing the green biomass and the LAI evolution through time, and the LSM using this information in the computation of the land surface fluxes and updating the soil water content in the root-zone. We explore the models on a case study of a water limited grass field in California. Results show that a simple vegetation model that simulates the living aboveground green biomass (i.e., with low parameterization and computational efforts) is able to accurately simulate the LAI. Results also highlight the importance of including the plant growth model in the LSM when studying the climate-soil-vegetation interactions and the impact of watershed management practices on the scarce water resources over moderate to long time scales. The inclusion of the vegetation model in the LSM is demonstrated to be essential for assessing the

  3. Water resources data for Indiana, water year 1993. Water-data report (Annual), 1 October 1992-30 September 1993

    SciTech Connect

    Stewart, J.A.; Keeton, C.R.; Benedict, B.L.; Hammil, L.E.

    1994-05-01

    Water resources data for the 1993 water year for Indiana consist of records of discharge, stage, and water quality of streams and wells; reservoirs stage and currents; and water levels in lakes and wells. This report contains records of discharge for 175 stream-gaging stations, stage for 5 stream stations, 1 sediment station, stage and contents for 1 reservoir, water quality for 3 streams, and water levels for 80 lakes and 94 observation wells.

  4. Water resources data for Indiana, water year 1994. Water-data report (Annual), 1 October 1993-30 September 1994

    SciTech Connect

    Stewart, J.A.; Keeton, C.R.; Benedict, B.L.; Hammil, L.E.

    1995-05-01

    Water resources data for the 1994 water year for Indiana consists of records of discharge, stage, and water quality of streams and wells; reservoirs stage and contents; and water levels in lakes and wells. This report contains records for discharge at 167 stream-gaging stations, stage for 6 stream stations, 1 sediment station, stage and contents for 1 reservoir, water quality for 2 streams, and water levels for 80 lakes and 94 observation wells.

  5. Water resources data for Indiana, water year 1992. Water-data report (Annual), 1 October 1991-30 September 1992

    SciTech Connect

    Stewart, J.A.; Keeton, C.R.; Benedict, B.L.; Hammil, L.E.

    1993-04-01

    Water resources data for the 1992 water year for Indiana consist of records of discharge, stage, and water quality of streams and wells; reservoir stage and contents; and water levels in lakes and wells. The report contains records of discharge for 175 stream-gaging stations, stage for 7 stream stations, 1 sediment station, stage and contents for 1 reservoir, water quality for 3 streams, and water levels for 80 lakes and 94 observation wells.

  6. Annual cycles of deep-ocean biogeochemical export fluxes in subtropical and subantarctic waters, southwest Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Nodder, Scott D.; Chiswell, Stephen M.; Northcote, Lisa C.

    2016-04-01

    The annual cycles of particle fluxes derived from moored sediment trap data collected during 2000-2012 in subtropical (STW) and subantarctic waters (SAW) east of New Zealand are presented. These observations are the most comprehensive export flux time series from temperate Southern Hemisphere latitudes to date. With high levels of variability, fluxes in SAW were markedly lower than in STW, reflecting the picophytoplankton-dominated communities in the iron-limited, high nutrient-low chlorophyll SAW. Austral spring chlorophyll blooms in surface STW were near synchronous with elevated fluxes of bio-siliceous, carbonate, and organic carbon-rich materials to the deep ocean, probably facilitated by diatom and/or coccolithophorid sedimentation. Lithogenic fluxes were also high in STW, compared to SAW, reflecting proximity to the New Zealand landmass. In contrast, the highest biogenic fluxes in SAW occurred in spring when surface chlorophyll concentrations were low, while highest annual chlorophyll concentrations were in summer with no associated flux increase. We hypothesize that the high spring export in SAW results from subsurface chlorophyll accumulation that is not evident from remote-sensing satellites. This material was also rich in biogenic silica, perhaps related to the preferential export of diatoms and other silica-producing organisms, such as silicoflagellates and radiolarians. Organic carbon fluxes in STW are similar to that of other mesotrophic to oligotrophic waters (˜6-7 mg C m-2 d-1), whereas export from SAW is below the global average (˜3 mg C m-2 d-1). Regional differences in flux across the SW Pacific and Tasman region reflect variations in physical processes and ecosystem structure and function.

  7. Inter-Annual Variability in Stream Water Temperature, Microclimate and Heat Exchanges: a Comparison of Forest and Moorland Environments

    NASA Astrophysics Data System (ADS)

    Garner, G.; Hannah, D. M.; Malcolm, I.; Sadler, J. P.

    2012-12-01

    Riparian forest is recognised as important for moderating stream temperature variability and has the potential to mitigate thermal extremes in a changing climate. Previous research on the heat exchanges controlling water column temperature has often been short-term or seasonally-constrained, with the few multi-year studies limited to a maximum of two years. This study advances previous work by providing a longer-term perspective which allows assessment of inter-annual variability in stream temperature, microclimate and heat exchange dynamics between a semi-natural woodland and a moorland (no trees) reach of the Girnock Burn, a tributary of the Scottish Dee. Automatic weather stations collected 15-minute data over seven consecutive years, which to our knowledge is a unique data set in providing the longest term perspective to date on stream temperature, microclimate and heat exchange processes. Results for spring-summer indicate that the presence of a riparian canopy has a consistent effect between years in reducing the magnitude and variability of mean daily water column temperature and daily net energy totals. Differences in the magnitude and variability in net energy fluxes between the study reaches were driven primarily by fluctuations in net radiation and latent heat fluxes in response to between- and within-year variability in growth of the riparian forest canopy at the forest and prevailing weather conditions at both the forest and moorland. This research provides new insights on the inter-annual variability of stream energy exchanges for moorland and forested reaches under a wide range of climatological and hydrological conditions. The findings therefore provide a more robust process basis for modelling the impact of changes in forest practice and climate change on river thermal dynamics.

  8. Evaporation, transpiration, and ecosystem water use efficiency in a multi-annual sugarcane production system in Hawai’i, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Food and biofuel production will require practices that increase water use efficiency in order to have future sustainability in a water-constrained environment. One possible practice is the use of food and energy crops with multi-annual growing periods, which could reduce bare soil evaporation. We...

  9. 25 CFR 171.510 - How does BIA calculate my annual operation and maintenance assessment if supplemental water is...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false How does BIA calculate my annual operation and maintenance assessment if supplemental water is available on the irrigation facility servicing my farm unit? 171.510 Section 171.510 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE...

  10. Asotin Creek ISCO Water Sample Data Summary: Water Year 2002, Annual Report 2001-2002.

    SciTech Connect

    Peterson, Stacia

    2003-08-01

    The Pomeroy Ranger District operates 3 automated water samplers (ISCOs) in the Asotin Creek drainage in cooperation with the Asotin Model Watershed. The samplers are located on Asotin Creek: Asotin Creek at the mouth, Asotin Creek at Koch site, and South Fork Asotin Creek above the forks. At the end of Water Year (WY) 2001 we decided to sample from Oct. 1 through June 30 of each water year. This decision was based on the difficulty of obtaining good low flow samples, since the shallow depth of water often meant that instrument intakes were on the bed of the river and samples were contaminated with bed sediments. The greatest portion of suspended sediment is transported during the higher flows of fall and especially during the spring snow runoff period, and sampling the shorter season should allow characterization of the sediment load of the river. The ISCO water samplers collected a daily composite sample of 4 samples per day into one bottle at 6-hour intervals until late March when they were reprogrammed to collect 3 samples per day at 8-hour intervals. This was done to reduce battery use since battery failure had become an ongoing problem. The water is picked up on 24-day cycles and brought to the Forest Service Water Lab in Pendleton, OR. The samples are analyzed for total suspended solids (TSS), conductivity, and turbidity. A total dissolved solids value is estimated based on conductivity. The USGS gage, Asotin Creek at the mouth, No.13335050 has been discontinued and there are no discharge records available for this period.

  11. Limiter

    DOEpatents

    Cohen, Samuel A.; Hosea, Joel C.; Timberlake, John R.

    1986-01-01

    A limiter with a specially contoured front face accommodates the various power scrape-off distances .lambda..sub.p, which depend on the parallel velocity, V.sub..parallel., of the impacting particles. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution.

  12. Response of larch root development to annual changes of water conditions in eastern Siberia

    NASA Astrophysics Data System (ADS)

    Takenaka, Chisato; Miyahara, Mie; Ohta, Takeshi; Maximov, Trofim C.

    2016-06-01

    Eastern Siberia is characterized by continuous permafrost, and has recently been exposed to the effects of climate change. Larch, which is the dominant tree species, has been subject to major environmental changes including fluctuations in soil water content. The purpose of this study was to clarify the responses of mature larch tree roots to changes in soil water conditions. We established a treatment plot in a larch forest, and artificially changed the soil water conditions by covering the ground surface with a vinyl sheet, and from 2004 to 2006 monitored root development through root windows. The vinyl sheet maintained high levels of soil water content, even though the ambient conditions varied from dry in 2004 to wet in 2005 and dry in 2006. In the treatment plot the plants adapted to the wet conditions by decreasing vertical root development. In contrast, roots of plants in the control plot developed to the subsurface layer, even in 2005, and did not develop vertically in 2006 despite the drought. We conclude that larch adapted to the annual changes in soil water content by changing the vertical distribution of roots, and that this reflected a memory effect.

  13. Optimizing the use of limited water in agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    About 92% of freshwater withdrawals in Uzbekistan are used for irrigation, whereas in the United States, freshwater withdrawls account for about 33% of the total use. In Uzbekistan, most of the water suitable for irrigation has already been allocated. In the United States, groundwater depletion and ...

  14. Ecological optimality in water-limited natural soil-vegetation systems. II - Tests and applications

    NASA Technical Reports Server (NTRS)

    Eagleson, P. S.; Tellers, T. E.

    1982-01-01

    The long-term optimal climatic climax soil-vegetation system is defined for several climates according to previous hypotheses in terms of two free parameters, effective porosity and plant water use coefficient. The free parameters are chosen by matching the predicted and observed average annual water yield. The resulting climax soil and vegetation properties are tested by comparison with independent observations of canopy density and average annual surface runoff. The climax properties are shown also to satisfy a previous hypothesis for short-term optimization of canopy density and water use coefficient. Using these hypotheses, a relationship between average evapotranspiration and optimum vegetation canopy density is derived and is compared with additional field observations. An algorithm is suggested by which the climax soil and vegetation properties can be calculated given only the climate parameters and the soil effective porosity. Sensitivity of the climax properties to the effective porosity is explored.

  15. Annual yield and selected hydrologic data for the Arkansas River Basin compact, Arkansas-Oklahoma, 1985 water year

    USGS Publications Warehouse

    Moore, M.A.; Lamb, T.E.

    1986-01-01

    The computed annual yield and deficiency of the subbasins as defined in the Arkansas River Compact, Arkansas-Oklahoma, are given in tables. Actual runoff from the subbasins and depletion caused by major reservoirs in the compact area are also given in tabular form. Monthly, maximum, minimum, and mean discharges are shown for the 14 streamflow stations used in computing annual yield. Water-quality data are shown for four sites in the compact area. (USGS)

  16. A method to derive the relationship between the annual and short-term air quality limits--analysis using the WHO Air Quality Guidelines for health protection.

    PubMed

    Lai, Hak-Kan; Hedley, Anthony J; Thach, Thuan-Quoc; Wong, Chit-Ming

    2013-09-01

    The World Health Organization (WHO) Air Quality Guidelines (AQG) were launched in 2006, but gaps remain in evidence on health impacts and relationships between short-term and annual AQG needed for health protection. We tested whether relationships between WHO short-term and annual AQG for particulates (PM10 and PM2.5) and nitrogen dioxide (NO2) are concordant worldwide and derived the annual limits for sulfur dioxide (SO2) and ozone (O3) based on the short-term AQG. We obtained air pollutant data over seven years (2004-2010) in seven cities from Asia-Pacific, North America and Europe. Based on probability distribution concept using maximum as the short-term limit and arithmetic mean as the annual limit, we developed a new method to derive limit value one from another in each paired limits for each pollutant with capability to account for allowable exceedances. We averaged the limit derived each year for each city, then used meta-analysis to pool the limit values in all cities. Pooled mean short-term limit for NO2 (140.5μg/m(3) [130.6-150.4]) was significantly lower than the WHO AQG of 200μg/m(3) while for PM10 (46.4μg/m(3) [95CI:42.1-50.7]) and PM2.5 (28.6μg/m(3) [24.5-32.6]) were not significantly different from the WHO AQG of 50 and 25μg/m(3) respectively. Pooled mean annual limits for SO2 and O3 were 4.6μg/m(3) [3.7-5.5] and 27.0μg/m(3) [21.7-32.2] respectively. Results were robust in various sensitivity analyses. The distribution relationships between the current WHO short-term and annual AQG are supported by empirical data from seven cities for PM10 and PM2.5, but not for NO2. The short-term AQG for NO2 should be lowered for concordance with the selected annual AQG for health protection.

  17. Exploring the limits of the terrestrial fresh water cycle

    NASA Astrophysics Data System (ADS)

    van der Ent, Ruud; Wang-Erlandsson, Lan; Keys, Patrick; Savenije, Hubert

    2014-05-01

    Precipitation is the ultimate source of life on this planet: it makes our crops grow, provides drinking water, feeds rivers and replenishes groundwater aquifers. Climate modelling studies estimate changes in precipitation due to increased greenhouse gas emissions and climate impact studies use those estimates as input to their (hydrological) models to predict future water availability and societal impact. However, humans also significantly alter the land surface by, for example, deforestation and irrigation, which is not frequently taken into account in our climate studies. Here, we present an overview of several papers in the field of moisture recycling, published by our group, that show the extent to which terrestrial evaporation influences terrestrial precipitation. It is found that 38% of the terrestrial precipitation originates from terrestrial evaporation and that 58% of all terrestrial evaporation recycles, and return again as terrestrial precipitation. Knowing this, it is clear that evaporation is not necessary a loss to the hydrological cycle. We show that in some cases even transpiration during the dry season can act as a moisture source for a distant region. To assess the vulnerability of a region to local and remote land use changes we propose the concept of the precipitationshed, which maps out a region's precipitation sources. Our results are useful in mapping out possible land use change threats, but also opportunities to safeguard our water resources in the Anthropocene.

  18. Water resources data for Alabama, water year 1992. Water-data report (Annual), 1 October 1991-30 September 1992

    SciTech Connect

    Pearman, J.L.; Sedberry, F.C.; Stricklin, V.E.; Cole, P.W.

    1993-03-01

    Water resources data for the 1992 water year for Alabama consist of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels in wells. The report includes records on both surface and ground water in the State. Specifically, it contains: (1) discharge records for 100 streamflow-gaging stations, for 63 partial-record or miscellaneous streamflow stations; (2) stage and content records for 13 lakes and reservoirs and stage at 34 stations; (3) water-quality records for 26 streamflow-gaging stations, 7 lake stations, for 32 ungaged streamsites, and for 1 precipitation station; (4) water temperature and specific conductance at 23 surface-water stations; (5) dissolved oxygen at 8 stations; (6) sediment data at 18 stations; and (7) water-level records for 3 recording observation wells and 59 periodic observation wells. Discharge records for a few pertinent stations in bordering States are also included in the report.

  19. Water resources data for Indiana, water year 1995. Water-data report (Annual), 1 October 1994-30 September 1995

    SciTech Connect

    Stewart, J.A.; Keeton, C.R.; Benedict, B.L.; Hammil, L.E.

    1996-06-01

    Water resources data for the 1995 water year for Indiana consists of records of discharge, stage, and water quality of streams and wells; reservoir stage and contents; and waterlevels in lakes and wells. The report contains records of discharge for 166 stream-gaging stations, stage for 6 stream stations, stage and contents for 1 reservoir, water quality for 1 stream, and water levels for 80 lakes and 94 observation wells. These data represent that part of the National Water Data System operated by the U.S. Geological Survey in Indiana in cooperation with State and Federal agencies.

  20. Impact of water table level on annual carbon and greenhouse gas balances of a restored peat extraction area

    NASA Astrophysics Data System (ADS)

    Järveoja, Järvi; Peichl, Matthias; Maddison, Martin; Soosaar, Kaido; Vellak, Kai; Karofeld, Edgar; Teemusk, Alar; Mander, Ülo

    2016-05-01

    Peatland restoration may provide a potential after-use option to mitigate the negative climate impact of abandoned peat extraction areas; currently, however, knowledge about restoration effects on the annual balances of carbon (C) and greenhouse gas (GHG) exchanges is still limited. The aim of this study was to investigate the impact of contrasting mean water table levels (WTLs) on the annual C and GHG balances of restoration treatments with high (ResH) and low (ResL) WTL relative to an unrestored bare peat (BP) site. Measurements of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes were conducted over a full year using the closed chamber method and complemented by measurements of abiotic controls and vegetation cover. Three years following restoration, the difference in the mean WTL resulted in higher bryophyte and lower vascular plant cover in ResH relative to ResL. Consequently, greater gross primary production and autotrophic respiration associated with greater vascular plant cover were observed in ResL compared to ResH. However, the means of the measured net ecosystem CO2 exchanges (NEE) were not significantly different between ResH and ResL. Similarly, no significant differences were observed in the respective means of CH4 and N2O exchanges. In comparison to the two restored sites, greater net CO2, similar CH4 and greater N2O emissions occurred in BP. On the annual scale, ResH, ResL and BP were C sources of 111, 103 and 268 g C m-2 yr-1 and had positive GHG balances of 4.1, 3.8 and 10.2 t CO2 eq ha-1 yr-1, respectively. Thus, the different WTLs had a limited impact on the C and GHG balances in the two restored treatments 3 years following restoration. However, the C and GHG balances in ResH and ResL were considerably lower than in BP due to the large reduction in CO2 emissions. This study therefore suggests that restoration may serve as an effective method to mitigate the negative climate impacts of abandoned peat extraction areas.

  1. Water resources data for Alabama, water year 1994. Water-data report (Annual), 1 October 1993-30 September 1994

    SciTech Connect

    Pearman, J.L.; Stricklin, V.E.; Cole, P.W.

    1995-03-01

    Water resources data for the 1994 water year for Alabama consist of records of stage, discharge, and water quality of streams; stages and contents of lakes and reservoirs; and water levels in wells. This report includes records on both surface and ground water in the State. Specifically, it contains: (1) discharge records for 104 streamflow-gaging stations, for 77 partial-record or miscellaneous streamflow stations; (2) stage and content records for 13 lakes and reservoirs and stage or elevation at 33 stations; (3) water-quality records for 23 streamflow-gaging stations, 3 lake stations, for 70 ungaged streamsites, and for 1 precipitation station; (4) water temperature and specific conductance at 17 surface-water stations; (5) dissolved oxygen at 7 stations; (6) sediment data at 43 stations; and (7) water-level records at 4 recording observation wells and 56 periodic observation wells. Also included are lists of active and discontinued continuous-record surface-water discharge stations, continuous-record surface-water stage stations, continuous-record surface-water-quality stations, and partial-record and miscellaneous surface-water-quality stations.

  2. Derivation and implementation of an annual limit on intake and a derived air concentration value for uranium mill tailings

    SciTech Connect

    Reif, R.H.; Andrews, D.W.

    1995-06-01

    Monitoring workers and work areas at the Department of Energy Uranium Mill Tailings Remedial Action Project sites is complex because all radionuclides in the {sup 238}U and {sup 235}U decay chains may be present in an airborne uranium mill tillings matrix. Previous monitoring practices involved isotopic analysis of the air filter to determine the activity of each radionuclide of concern and comparing the results to the specified derived air concentration. The annual limit on intake and derived air concentration values have been derived here for the uranium mill tailings matrix to simplify the procedure for evaluation of air monitoring results and assessment of the need for individual monitoring. Implementation of the derived air concentration for uranium mill tailings involves analyzing air samples for long-lived gross alpha activity and comparing the activity concentration to the derived air concentration. Health physics decisions regarding assessment of airborne concentrations is more cost-effective because isotopic analysis of air samples is not necessary. 12 refs., 2 tabs.

  3. Annual Storm Water Report for the Y-12 National Security Complex Oak Ridge, Tennessee

    SciTech Connect

    2013-12-01

    This is the second annual storm water report prepared in accordance with the National Pollutant Discharge Elimination System (NPDES) permit issued to the Y-12 National Security Complex (Y-12 Complex) on December 1, 2011, and the corresponding Y-12 Storm Water Pollution Prevention Plan (SWP3) which became effective on September 7, 2012. However, Appendix A does contain some analytical data gathered under the previous NPDES permit and SWP3 for comparison purposes. The quality of storm water exiting the Y-12 Complex via East Fork Poplar Creek remained relatively stable from 2012 to 2013. However, there was one largely unexpected high concentration of mercury noted in an area that is not known to have previously been a mercury use area. This was noted in Sector AA, Outfall 014. This outfall is normally sampled on a rotating basis but, due this elevated concentration, will be sampled again in 2014. The Y-12 Complex will continue to implement appropriate BMPs and reduce outside material storage ares where possible. Emphasis will continue to be placed on site inspections and timely implementation of proper storm water control measures.

  4. Water resources data for Michigan, water year 1995. Water-data report (Annual), 1 October 1994-30 September 1995

    SciTech Connect

    Blumer, S.P.; Behrendt, T.E.; Ellis, J.M.; Minnerick, R.J.; LeuVoy, R.L.

    1996-05-01

    Water resources data for the 1995 water year for Michigan consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and ground water levels. This report contains discharge records for 148 streamflow-gaging stations; stage only records for 2 stream-gaging stations and 19 lake-gaging stations; stage and contents for 4 lakes and reservoirs; water-quality records for 16 streamflow-gaging stations and 1 lake-gaging station; water-level records for 42 ground-water wells. Also included are 29 crest-stage partial-record stations and 2 low-flow partial-record stations. Additional water data were collected at various sites not involved in the systematic data-collection-program. Miscellaneous data were collected at 74 measuring sites.

  5. 25 CFR 171.710 - Can I receive irrigation water if I am granted an Annual Assessment Waiver?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Can I receive irrigation water if I am granted an Annual Assessment Waiver? 171.710 Section 171.710 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Non-Assessment Status § 171.710 Can I receive irrigation water if I am granted an...

  6. Low-oxygen waters limited habitable space for early animals

    PubMed Central

    Tostevin, R.; Wood, R. A.; Shields, G. A.; Poulton, S. W.; Guilbaud, R.; Bowyer, F.; Penny, A. M.; He, T.; Curtis, A.; Hoffmann, K. H.; Clarkson, M. O.

    2016-01-01

    The oceans at the start of the Neoproterozoic Era (1,000–541 million years ago, Ma) were dominantly anoxic, but may have become progressively oxygenated, coincident with the rise of animal life. However, the control that oxygen exerted on the development of early animal ecosystems remains unclear, as previous research has focussed on the identification of fully anoxic or oxic conditions, rather than intermediate redox levels. Here we report anomalous cerium enrichments preserved in carbonate rocks across bathymetric basin transects from nine localities of the Nama Group, Namibia (∼550–541 Ma). In combination with Fe-based redox proxies, these data suggest that low-oxygen conditions occurred in a narrow zone between well-oxygenated surface waters and fully anoxic deep waters. Although abundant in well-oxygenated environments, early skeletal animals did not occupy oxygen impoverished regions of the shelf, demonstrating that oxygen availability (probably >10 μM) was a key requirement for the development of early animal-based ecosystems. PMID:27659064

  7. Low-oxygen waters limited habitable space for early animals.

    PubMed

    Tostevin, R; Wood, R A; Shields, G A; Poulton, S W; Guilbaud, R; Bowyer, F; Penny, A M; He, T; Curtis, A; Hoffmann, K H; Clarkson, M O

    2016-09-23

    The oceans at the start of the Neoproterozoic Era (1,000-541 million years ago, Ma) were dominantly anoxic, but may have become progressively oxygenated, coincident with the rise of animal life. However, the control that oxygen exerted on the development of early animal ecosystems remains unclear, as previous research has focussed on the identification of fully anoxic or oxic conditions, rather than intermediate redox levels. Here we report anomalous cerium enrichments preserved in carbonate rocks across bathymetric basin transects from nine localities of the Nama Group, Namibia (∼550-541 Ma). In combination with Fe-based redox proxies, these data suggest that low-oxygen conditions occurred in a narrow zone between well-oxygenated surface waters and fully anoxic deep waters. Although abundant in well-oxygenated environments, early skeletal animals did not occupy oxygen impoverished regions of the shelf, demonstrating that oxygen availability (probably >10 μM) was a key requirement for the development of early animal-based ecosystems.

  8. Low-oxygen waters limited habitable space for early animals

    NASA Astrophysics Data System (ADS)

    Tostevin, R.; Wood, R. A.; Shields, G. A.; Poulton, S. W.; Guilbaud, R.; Bowyer, F.; Penny, A. M.; He, T.; Curtis, A.; Hoffmann, K. H.; Clarkson, M. O.

    2016-09-01

    The oceans at the start of the Neoproterozoic Era (1,000-541 million years ago, Ma) were dominantly anoxic, but may have become progressively oxygenated, coincident with the rise of animal life. However, the control that oxygen exerted on the development of early animal ecosystems remains unclear, as previous research has focussed on the identification of fully anoxic or oxic conditions, rather than intermediate redox levels. Here we report anomalous cerium enrichments preserved in carbonate rocks across bathymetric basin transects from nine localities of the Nama Group, Namibia (~550-541 Ma). In combination with Fe-based redox proxies, these data suggest that low-oxygen conditions occurred in a narrow zone between well-oxygenated surface waters and fully anoxic deep waters. Although abundant in well-oxygenated environments, early skeletal animals did not occupy oxygen impoverished regions of the shelf, demonstrating that oxygen availability (probably >10 μM) was a key requirement for the development of early animal-based ecosystems.

  9. Water resources data for Minnesota, water year 1996. Water-data report (Annual), 1 October 1995-30 September 1996

    SciTech Connect

    Mitton, G.B.; Wakeman, E.S.; Guttormson, K.G.

    1997-04-03

    This report contains discharge records for 100 stream-gaging stations; stage and contents for 14 lakes and reservoirs; water quality for 34 stream-gaging stations; and water levels for 15 observation wells. Also included are 87 high-flow partial-record stations, and rainfall totals and water quality for one precipitation station.

  10. Water resources data for Indiana, water year 1996. Water-data report (Annual), 1 October 1995-30 September 1996

    SciTech Connect

    Stewart, J.A.; Keeton, C.R.; Benedict, B.L.; Hammil, L.E.

    1997-05-01

    This report contains records of discharge for 166 stream-gaging stations, stage for 6 stream stations, stage and contents for 1 reservoir, water quality for 2 streams, and water levels for 80 lakes and 94 observation wells. Also included are records of 39 water-quality sites, not part of the systematic data-collection program, and are shown as miscellaneous samplings.

  11. Detection limits and cost comparisons of human- and gull-associated conventional and quantitative PCR assays in artificial and environmental waters

    USGS Publications Warehouse

    Riedel, Timothy E.; Zimmer-Faust, Amity G.; Thulsiraj, Vanessa; Madi, Tania; Hanley, Kaitlyn T.; Ebentier, Darcy L.; Byappanahalli, Muruleedhara N.; Layton, Blythe; Raith, Meredith; Boehm, Alexandria B.; Griffith, John F.; Holden, Patricia A.; Shanks, Orin C.; Weisberg, Stephen B.; Jay, Jennifer A.

    2014-01-01

    Some molecular methods for tracking fecal pollution in environmental waters have both PCR and quantitative PCR (qPCR) assays available for use. To assist managers in deciding whether to implement newer qPCR techniques in routine monitoring programs, we compared detection limits (LODs) and costs of PCR and qPCR assays with identical targets that are relevant to beach water quality assessment. For human-associated assays targeting Bacteroidales HF183 genetic marker, qPCR LODs were 70 times lower and there was no effect of target matrix (artificial freshwater, environmental creek water, and environmental marine water) on PCR or qPCR LODs. The PCR startup and annual costs were the lowest, while the per reaction cost was 62% lower than the Taqman based qPCR and 180% higher than the SYBR based qPCR. For gull-associated assays, there was no significant difference between PCR and qPCR LODs, target matrix did not effect PCR or qPCR LODs, and PCR startup, annual, and per reaction costs were lower. Upgrading to qPCR involves greater startup and annual costs, but this increase may be justified in the case of the human-associated assays with lower detection limits and reduced cost per sample.

  12. Detection limits and cost comparisons of human- and gull-associated conventional and quantitative PCR assays in artificial and environmental waters.

    PubMed

    Riedel, Timothy E; Zimmer-Faust, Amity G; Thulsiraj, Vanessa; Madi, Tania; Hanley, Kaitlyn T; Ebentier, Darcy L; Byappanahalli, Muruleedhara; Layton, Blythe; Raith, Meredith; Boehm, Alexandria B; Griffith, John F; Holden, Patricia A; Shanks, Orin C; Weisberg, Stephen B; Jay, Jennifer A

    2014-04-01

    Some molecular methods for tracking fecal pollution in environmental waters have both PCR and quantitative PCR (qPCR) assays available for use. To assist managers in deciding whether to implement newer qPCR techniques in routine monitoring programs, we compared detection limits (LODs) and costs of PCR and qPCR assays with identical targets that are relevant to beach water quality assessment. For human-associated assays targeting Bacteroidales HF183 genetic marker, qPCR LODs were 70 times lower and there was no effect of target matrix (artificial freshwater, environmental creek water, and environmental marine water) on PCR or qPCR LODs. The PCR startup and annual costs were the lowest, while the per reaction cost was 62% lower than the Taqman based qPCR and 180% higher than the SYBR based qPCR. For gull-associated assays, there was no significant difference between PCR and qPCR LODs, target matrix did not effect PCR or qPCR LODs, and PCR startup, annual, and per reaction costs were lower. Upgrading to qPCR involves greater startup and annual costs, but this increase may be justified in the case of the human-associated assays with lower detection limits and reduced cost per sample.

  13. 75 FR 65507 - U.S.-Russia Polar Bear Commission Adopts an Annual Taking Limit for the Alaska-Chukotka Polar...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-25

    ... Fish and Wildlife Service U.S.-Russia Polar Bear Commission Adopts an Annual Taking Limit for the Alaska-Chukotka Polar Bear Population AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice. SUMMARY: On June 9, 2010, by unanimous vote, the U.S.-Russia Polar Bear Commission established by...

  14. 26 CFR 1.401(e)-5 - Limitation of contribution and benefit bases to first $100,000 of annual compensation in case of...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... first $100,000 of annual compensation in case of plans covering self-employed individuals. 1.401(e)-5... of plans covering self-employed individuals. (a) General rules—General rule. (1) Under section 401(a... to special limitations for self-employed individuals); section 413(b)(7) (relating to...

  15. 26 CFR 1.401(e)-5 - Limitation of contribution and benefit bases to first $100,000 of annual compensation in case of...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... first $100,000 of annual compensation in case of plans covering self-employed individuals. 1.401(e)-5... of plans covering self-employed individuals. (a) General rules—General rule. (1) Under section 401(a... to special limitations for self-employed individuals); section 413(b)(7) (relating to...

  16. 26 CFR 1.401(e)-5 - Limitation of contribution and benefit bases to first $100,000 of annual compensation in case of...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... first $100,000 of annual compensation in case of plans covering self-employed individuals. 1.401(e)-5... covering self-employed individuals. (a) General rules—General rule. (1) Under section 401(a)(17), a plan... self-employed individuals); section 413(b)(7) (relating to determination of limitations provided...

  17. 26 CFR 1.401(e)-5 - Limitation of contribution and benefit bases to first $100,000 of annual compensation in case of...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... first $100,000 of annual compensation in case of plans covering self-employed individuals. 1.401(e)-5... of plans covering self-employed individuals. (a) General rules—General rule. (1) Under section 401(a... to special limitations for self-employed individuals); section 413(b)(7) (relating to...

  18. 26 CFR 1.401(e)-5 - Limitation of contribution and benefit bases to first $100,000 of annual compensation in case of...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... first $100,000 of annual compensation in case of plans covering self-employed individuals. 1.401(e)-5... of plans covering self-employed individuals. (a) General rules—General rule. (1) Under section 401(a... to special limitations for self-employed individuals); section 413(b)(7) (relating to...

  19. Annual water quality data report for the Waste Isolation Pilot Plant

    SciTech Connect

    Lyon, M.L. )

    1989-04-01

    This is the fourth Annual Water Quality Data Report for the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico. The WIPP project is operated by the United States Department of Energy (DOE) for the purpose of providing a research and development facility to demonstrate the safe disposal of transuranic radioactive wastes generated by the defense activities of the United States Government. This report presents water quality data collected from January 1988 through December 1988 from 16 designated pre-operational (WIPP facility) monitoring wells, two additional wells, and 10 privately-owned wells in the vicinity of the WIPP. Additionally, water samples were collected from the Air Intake Shaft during shaft construction activities at the WIPP. This report lists pertinent information regarding the monitoring wells sampled, sampling zone, dates pumped, and types of samples collected during 1988. Comparative data from previous samplings of all wells can be found in Uhland and Randall (1986), Uhland et al. (1987), Randall et al. (1988), as well as in this report. The data reported by the Water Quality Sampling Program in this and previous reports indicate that serial sampling is a very useful tool in determining sample representativeness from wells in the WIPP vicinity. Serial sample field chemistry data are demonstrated to be highly accurate and precise as indicated by the excellent overall average percent spike recovery values and low RPD values reported for the sampling events. Serial sample field chemistry data and laboratory water quality parameter analyses gathered by the WQSP since January 1985 are the foundation for a pre-operational water quality baseline at the WIPP. 32 refs., 66 figs., 96 tabs.

  20. Fresh Water Generation from Aquifer-Pressured Carbon Storage: Annual Report FY09

    SciTech Connect

    Wolery, T; Aines, R; Hao, Y; Bourcier, W; Wolfe, T; Haussman, C

    2009-11-25

    This project is establishing the potential for using brine pressurized by Carbon Capture and Storage (CCS) operations in saline formations as the feedstock for desalination and water treatment technologies including reverse osmosis (RO) and nanofiltration (NF). The aquifer pressure resulting from the energy required to inject the carbon dioxide provides all or part of the inlet pressure for the desalination system. Residual brine is reinjected into the formation at net volume reduction, such that the volume of fresh water extracted balances the volume of CO{sub 2} injected into the formation. This process provides additional CO{sub 2} storage capacity in the aquifer, reduces operational risks (cap-rock fracturing, contamination of neighboring fresh water aquifers, and seismicity) by relieving overpressure in the formation, and provides a source of low-cost fresh water to offset costs or operational water needs. This multi-faceted project combines elements of geochemistry, reservoir engineering, and water treatment engineering. The range of saline formation waters is being identified and analyzed. Computer modeling and laboratory-scale experimentation are being used to examine mineral scaling and osmotic pressure limitations. Computer modeling is being used to evaluate processes in the storage aquifer, including the evolution of the pressure field. Water treatment costs are being evaluated by comparing the necessary process facilities to those in common use for seawater RO. There are presently limited brine composition data available for actual CCS sites by the site operators including in the U.S. the seven regional Carbon Sequestration Partnerships (CSPs). To work around this, we are building a 'catalog' of compositions representative of 'produced' waters (waters produced in the course of seeking or producing oil and gas), to which we are adding data from actual CCS sites as they become available. Produced waters comprise the most common examples of saline

  1. BOREAS RSS-8 BIOME-BGC SSA Simulation of Annual Water and Carbon Fluxes

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Kimball, John

    2000-01-01

    The BOREAS RSS-8 team performed research to evaluate the effect of seasonal weather and landcover heterogeneity on boreal forest regional water and carbon fluxes using a process-level ecosystem model, BIOME-BGC, coupled with remote sensing-derived parameter maps of key state variables. This data set contains derived maps of landcover type and crown and stem biomass as model inputs to determine annual evapotranspiration, gross primary production, autotrophic respiration, and net primary productivity within the BOREAS SSA-MSA, at a 30-m spatial resolution. Model runs were conducted over a 3-year period from 1994-1996; images are provided for each of those years. The data are stored in binary image format. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  2. Control factors and scale analysis of annual river water, sediments and carbon transport in China

    PubMed Central

    Song, Chunlin; Wang, Genxu; Sun, Xiangyang; Chang, Ruiying; Mao, Tianxu

    2016-01-01

    Under the context of dramatic human disturbances on river system, the processes that control the transport of water, sediment, and carbon from river basins to coastal seas are not completely understood. Here we performed a quantitative synthesis for 121 sites across China to find control factors of annual river exports (Rc: runoff coefficient; TSSC: total suspended sediment concentration; TSSL: total suspended sediment loads; TOCL: total organic carbon loads) at different spatial scales. The results indicated that human activities such as dam construction and vegetation restoration might have a greater influence than climate on the transport of river sediment and carbon, although climate was a major driver of Rc. Multiple spatial scale analyses indicated that Rc increased from the small to medium scale by 20% and then decreased at the sizable scale by 20%. TSSC decreased from the small to sizeable scale but increase from the sizeable to large scales; however, TSSL significantly decreased from small (768 g·m−2·a−1) to medium spatial scale basins (258 g·m−2·a−1), and TOCL decreased from the medium to large scale. Our results will improve the understanding of water, sediment and carbon transport processes and contribute better water and land resources management strategies from different spatial scales. PMID:27166177

  3. Control factors and scale analysis of annual river water, sediments and carbon transport in China

    NASA Astrophysics Data System (ADS)

    Song, Chunlin; Wang, Genxu; Sun, Xiangyang; Chang, Ruiying; Mao, Tianxu

    2016-05-01

    Under the context of dramatic human disturbances on river system, the processes that control the transport of water, sediment, and carbon from river basins to coastal seas are not completely understood. Here we performed a quantitative synthesis for 121 sites across China to find control factors of annual river exports (Rc: runoff coefficient; TSSC: total suspended sediment concentration; TSSL: total suspended sediment loads; TOCL: total organic carbon loads) at different spatial scales. The results indicated that human activities such as dam construction and vegetation restoration might have a greater influence than climate on the transport of river sediment and carbon, although climate was a major driver of Rc. Multiple spatial scale analyses indicated that Rc increased from the small to medium scale by 20% and then decreased at the sizable scale by 20%. TSSC decreased from the small to sizeable scale but increase from the sizeable to large scales; however, TSSL significantly decreased from small (768 g·m‑2·a‑1) to medium spatial scale basins (258 g·m‑2·a‑1), and TOCL decreased from the medium to large scale. Our results will improve the understanding of water, sediment and carbon transport processes and contribute better water and land resources management strategies from different spatial scales.

  4. New beach ridge type: severely limited fetch, very shallow water

    SciTech Connect

    Tanner, W.F.; Demirpolat, S.

    1988-09-01

    The southern end of Laguna Madre (Texas) north of the Rio Grande mouth is marked by very shallow water, wide tidal flats, lunettes, islands made of beach ridges, and lesser features. The number and variety of islands in the lagoon is remarkable. The lunettes (clay dunes) are made primarily of quartz sand and coarse silt. They are common 5-10 m high, irregular in shape, and steep sided. They were deposited from wind transport and did not migrate. Those that are islands in the lagoon predate present position of sea level. Islands made of beach ridges were built from the lagoon side. Photoanalysis, field work, and granulometry all show that this sand was not moved into these ridges by Gulf of Mexico waves. Trenches in 12 beach ridges showed horizontal bedding but neither low-angle nor steep cross-bedding (quite unlike swash-built beach ridges). The ridges were built by wind-tide lag effects, not from the swash. Therefore, these beach ridges are a new type, in addition to swash-built, eolian, and storm-surge ridges. Growth of the ridges appears to be completed.

  5. Annual and seasonal water storage changes detected from GRACE data in the La Plata Basin

    NASA Astrophysics Data System (ADS)

    Pereira, Ayelen; Pacino, María Cristina

    2012-12-01

    The gravity does not remain constant, but changes over time depending on the redistribution of the masses. Aquatic environments, like a river basin, perform important functions in nature such as control of climate, floods and nutrients; and they also provide goods and services for humanity. To monitor these environments at large spatial scales, the satellite gravity mission GRACE provides time-variable gravity field models that reflect the Earth's gravity field variations due to mass transport processes, like continental water storage variations. The La Plata Basin is the second largest in South America and is a sample of the abundance, variety and quality of natural resources and possibilities offered in connection with the production of goods and services. The objective of this work is to analyze GRACE capability to monitor the water storage variations in the La Plata Basin. Firstly, GRACE solutions from four different processing centers are used to estimate the gravity trend and gravity amplitude over this basin. Afterwards, the calculated hydrological signal is used to obtain mass change models over this hydrographic system's area, using two different methods and for the period from 2002 to 2009. Next, the annual and seasonal water storage changes from GRACE solutions are validated in Argentina by rainfall data over the time periods where extreme weather conditions took place. The results indicate that GRACE detected the variations of the continental water storage in the La Plata Basin, and particularly, it detected the important decrease in the South of the basin. Moreover, a coherency between the estimates of water mass changes and rainfall data was found, which shows that GRACE also detected extreme weather events (such as drought and intense rain episodes) that occurred in the 2004-2009 period in Argentina.

  6. Intra- and Inter-annual Fluorescence Intensity Variations in Drip Water, Heshang Cave, Central China: Implications for Speleothem Palaeoclimatology

    NASA Astrophysics Data System (ADS)

    Jin, L.; Hu, C.; Li, X.; Ruan, J.; Hartland, A.

    2015-12-01

    Cave drip water acts as a signal carrier for the soil-rock-air system leading to the capture of climatic and environmental information in stalagmites. This paper seeks to develop an understanding of the environmental and climatic factors which control fluorescence variations in dripwater from in Heshang Cave, Central China. This information is essential to unravelling the significance of organic fluorescence in stalagmites and its utility in quantitative paleoclimate reconstructions. On the seasonal time scale, drip water fluorescence is largely controlled by the decomposition and translocation of dissolved organic matter in the soil, related to climate factors like temperature and precipitation. On the inter-annual time scale, longer duration monitoring data in scarce, yet this is needed to fully comprehend the influence of climate in stalagmite fluorescence time series. This study presents nine consecutive years of monthly drip water fluorescence intensity and drip rate data from two perennial drip sites in Heshang Cave. Drip water fluorescence was generally characterized by intensities in spring/summer and low intensities in autumn/winter. In dry hydrologic years, little seasonality in fluorescence signals was observed, but the opposite was observed in wet years. On the inter-annual time scale, the annual mean intensities of drip water fluorescence positively correlated with local annual rainfall with a 1-year lag (R2HS4=0.94; R2HS6=0.74). This indicates that rainfall is the main control on total drip water fluorescence (integrating across a hydrologic year), despite significant degrees of intra-annual fluorescence variation being observed between wet and dry years. These findings are of direct relevance for paleoclimate reconstruction using fluorescence intensities in stalagmites from the Asian monsoon region. Key words: fluorescence; dissolved organic matter; drip water rates; seasonality; precipitation

  7. Compression Limit of Two-Dimensional Water Constrained in Graphene Nanocapillaries.

    PubMed

    Zhu, YinBo; Wang, FengChao; Bai, Jaeil; Zeng, Xiao Cheng; Wu, HengAn

    2015-12-22

    Evaluation of the tensile/compression limit of a solid under conditions of tension or compression is often performed to provide mechanical properties that are critical for structure design and assessment. Algara-Siller et al. recently demonstrated that when water is constrained between two sheets of graphene, it becomes a two-dimensional (2D) liquid and then is turned into an intriguing monolayer solid with a square pattern under high lateral pressure [ Nature , 2015 , 519 , 443 - 445 ]. From a mechanics point of view, this liquid-to-solid transformation characterizes the compression limit (or metastability limit) of the 2D monolayer water. Here, we perform a simulation study of the compression limit of 2D monolayer, bilayer, and trilayer water constrained in graphene nanocapillaries. At 300 K, a myriad of 2D ice polymorphs (both crystalline-like and amorphous) are formed from the liquid water at different widths of the nanocapillaries, ranging from 6.0 to11.6 Å. For monolayer water, the compression limit is typically a few hundred MPa, while for the bilayer and trilayer water, the compression limit is 1.5 GPa or higher, reflecting the ultrahigh van der Waals pressure within the graphene nanocapillaries. The compression-limit (phase) diagram is obtained at the nanocapillary width versus pressure (h-P) plane, based on the comprehensive molecular dynamics simulations at numerous thermodynamic states as well as on the Clapeyron equation. Interestingly, the compression-limit curves exhibit multiple local minima.

  8. Annual production of burrowing mayfly nymphs (Hexagenia spp.) in U.S. waters of Lake St. Clair

    USGS Publications Warehouse

    Edsall, Thomas A.; Haas, Robert C.; Adams, Jean V.

    2001-01-01

    Burrowing mayfly nymphs (Hexagenia spp.) were sampled monthly, September through October 1995 and April through August 1996, with a standard Ponar grab (538 cm2 jaw opening) at 16 stations in U.S. waters of Lake St. Clair. Annual production (production, P) was 0 to 477 mg dry weight/m2 at three stations where pollution and sediment grain-size distribution limited the population, and was 738 to 5,255 mg dry weight/m2 at the other 13 stations. The highest production value measured for Hexagenia in Lake St. Clair was about three times higher than the highest value reported for other areas in the northern United States and Canada (39° to 53° North latitude). The production-mean annual biomass (biomass, B) ratio (P/B) for Hexagenia in Lake St. Clair in 1995–96 was described by the straight line P = 2.4 B (R2 = 0.94). Adding published P/B data for other North American populations changed the relation only slightly to P = 2.5B (R2 = 0.96). A P/B ratio of 2.5 is consistent with the expected value for an aquatic insect with a 2-year life cycle and overlapping cohorts, and these data suggest this relation has general applicability for estimating production of Hexagenia in the northern United States and Canada. Size-class and seasonal partitioning of Hexagenia biomass and production were evident in the data. Both biomass and production were highest among nymphs 16.0 mm and larger, and biomass was highest in October and again in June, immediately before the annual emergence of subimagos. The large size of the mature nymphs and the concentration of biomass and production among the larger nymphs in the population is consistent with their importance in the diets of many fishes in the northern United States and Canada.

  9. Recycling harvest water to cultivate Chlorella zofingiensis under nutrient limitation for biodiesel production.

    PubMed

    Zhu, L D; Takala, J; Hiltunen, E; Wang, Z M

    2013-09-01

    Harvest water recycling for Chlorella zofingiensis re-cultivation under nutrient limitation was investigated. Using 100% harvest water, four cultures were prepared: Full medium, P-limited medium, N-limited medium and N- and P-limited medium, while another full medium was also prepared using 50% harvest water. The results showed that the specific growth rate and biomass productivity ranged from 0.289 to 0.403 day(-1) and 86.30 to 266.66 mg L(-1) day(-1), respectively. Nutrient-limited cultures witnessed much higher lipid content (41.21-46.21% of dry weight) than nutrient-full cultures (26% of dry weight). The N- and P-limited medium observed the highest FAME yield at 10.95% of dry weight, while the N-limited culture and P-limited culture shared the highest biodiesel productivity at 20.66 and 19.91 mg L(-1) day(-1), respectively. The experiment on harvest water recycling times demonstrated that 100% of the harvest water could be recycled twice with the addition of sufficient nutrients.

  10. Long-term trend and multi-annual variability of water temperature in the pristine Bela River basin (Slovakia)

    NASA Astrophysics Data System (ADS)

    Pekárová, Pavla; Miklánek, Pavol; Halmová, Dana; Onderka, Milan; Pekár, Ján; Kučárová, Katarína; Liová, Soňa; Škoda, Peter

    2011-04-01

    SummaryBiological processes in surface waters appreciably depend on temperature of water. This paper summarizes our investigations of water temperature in the Bela River. The Bela River is a mountainous stream not influenced by direct human activities, draining the headwaters of the Vah River basin in the Tatra National Park (TANAP), Slovakia. Our primary aim was to identify the long-term trends and multi-annual variability of the annual water temperature at the Podbanske gauging station, using temperature readings taken at 7.00 am for the period of 50 years (1959-2008). Long-term mean of the annual water temperature of the Bela River at the Podbanske gauging station (922 m a.s.l.) was 4.2 °C, the air temperature at Podbanske meteorological station (972 m a.s.l.) was 5.0 °C. Both, air and water temperature, show an increasing trend. While the air temperature within 50-years increased significantly by 1.5 °C, in the case of water temperature this increase was merely by 0.12 °C. On November 19, 2004, a wind-throw brushed the investigated area with an aftermath of 15.4% destroyed forest in the Bela basin, mainly along the area adjacent to the river. Therefore, in the second part of the study, the impact of the riparian vegetation growing along the river banks was evaluated for two distinctive periods, i.e. the period prior and after the wind-throw. We statistically analysed the changes in water temperature on 6-year time series of daily water temperature (November 2001 through November 2007). The results presented herein may be useful for defining boundary values for surface water temperature, as required by the EC Water Framework Directive.

  11. Hydrologic effects of annually diverting 131,000 acre-feet of water from Dillon Reservoir, central Colorado

    USGS Publications Warehouse

    Alley, William M.; Bauer, D.P.; Veenhuis, J.E.; Brennan, Robert

    1979-01-01

    Because of the increased demands for water in eastern Colorado, principally in the urbanizing Denver metropolitan area, increased diversions of water from Dillon Reservoir are planned. Estimates of end-of-month storage in Dillon Reservoir, assuming the reservoir was in place and 131,000 acre-feet of water were diverted from the reservoir each year, were reconstructed by mass balance for the 1931-77 water years. Based on the analysis, the annual maximum end-of-month drawdown below the elevation at full storage would have averaged 54 feet. The maximum end-of-month drawdown below the elevation at full storage would have been 171 feet. The mean-annual discharge-weighted dissolved-solids concentrations in the Colorado River near Glenwood Springs and Cameo, Colo., and Cisco, Utah, for the 1942-77 water years, were computed assuming an annual diversion of 131,000 acre-feet of water from Dillon Reservoir. The average increases in the dissolved-solids concentrations with the 131 ,000-acre-foot diversion were 15 to 16 milligrams per liter at the three sites. (Woodard-USGS)

  12. 1994 Environmental monitoring drinking water and nonradiological effluent programs annual report

    SciTech Connect

    Andersen, B.D.; Brock, T.A.; Meachum, T.R.

    1995-10-01

    EG&G Idaho, Inc., initiated monitoring programs for drinking water in 1988 and for nonradiological parameters and pollutants in liquid effluents in 1985. These programs were initiated for the facilities operated by EG&G Idaho for the US Department of Energy at the Idaho National Engineering Laboratory. On October 1, 1994, Lockheed Idaho Technologies Company (LITCO) replaced EG&G Idaho as the prime contractor at the INEL and assumed responsibility for these programs. Section I discusses the general site characteristics, the analytical laboratories, and sampling methodology general to both programs. Section 2, the Drinking Water Program, tracks the bacteriological, chemical, and radiological parameters required by State and Federal regulations. This section describes the drinking water monitoring activities conducted at 17 LITCO-operated production wells and 11 distribution systems. It also contains all of the drinking water parameters detected and the regulatory limits exceeded during calendar year 1994. In addition, groundwater quality is discussed as it relates to contaminants identified at the wellhead for LITCO production wells. Section 3 discusses the nonradiological liquid effluent monitoring results for 27 liquid effluent streams. These streams are presented with emphasis on calendar year 1994 activities. All parameter measurements and concentrations were below the Resource Conservation and Recovery Act toxic characteristics limits.

  13. Water resources data for North Carolina, water year 1995. Volume 2. Ground-water records. Water data report (Annual), 1 October 1994-30 September 1995

    SciTech Connect

    Smith, D.G.; George, E.D.; Breton, P.L.

    1996-06-01

    Water-resources data for the 1995 water year for North Carolina consist of records of ground-water levels and water quality of ground water; records of stage, discharge, and water quality of streams; and stage and contents of lakes and reservoirs. This report contains ground-water level data from 81 observation wells and ground-water quality data from 125 wells.

  14. Water resources data for North Carolina, water year 1993. Volume 2. Ground-water records. Water-data report (Annual), 1 October 1992-30 September 1993

    SciTech Connect

    Coble, R.W.; Smith, D.G.; Ragland, B.C.

    1994-04-13

    Water-resources data for the 1993 water year for North Carolina consist of records of ground-water levels and water quality of ground water; records of stage, discharge and water quality of streams; and stage and contents of lakes and reservoirs. This report contains ground-water level data from 82 observation wells and ground-water quality data from 41 wells.

  15. Water availability limits tolerance of apical damage in the Chilean tarweed Madia sativa

    NASA Astrophysics Data System (ADS)

    Gonzáles, Wilfredo L.; Suárez, Lorena H.; Molina-Montenegro, Marco A.; Gianoli, Ernesto

    2008-07-01

    Plant tolerance is the ability to reduce the negative impact of herbivory on plant fitness. Numerous studies have shown that plant tolerance is affected by nutrient availability, but the effect of soil moisture has received less attention. We evaluated tolerance of apical damage (clipping that mimicked insect damage) under two watering regimes (control watering and drought) in the tarweed Madia sativa (Asteraceae). We recorded number of heads with seeds and total number of heads as traits related to fitness. Net photosynthetic rate, water use efficiency, number of branches, shoot biomass, and the root:shoot biomass ratio were measured as traits potentially related to tolerance via compensatory responses to damage. In the drought treatment, damaged plants showed ≈43% reduction in reproductive fitness components in comparison with undamaged plants. In contrast, there was no significant difference in reproductive fitness between undamaged and damaged plants in the control watering treatment. Shoot biomass was not affected by apical damage. The number of branches increased after damage in both water treatments but this increase was limited by drought stress. Net photosynthetic rate increased in damaged plants only in the control watering treatment. Water use efficiency increased with drought stress and, in plants regularly watered, also increased after damage. Root:shoot ratio was higher in the low water treatment and damaged plants tended to reduce root:shoot ratio only in this water treatment. It is concluded that water availability limits tolerance to apical damage in M. sativa, and that putative compensatory mechanisms are differentially affected by water availability.

  16. 30 CFR 816.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 816.42 Section 816.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-SURFACE MINING ACTIVITIES § 816.42 Hydrologic balance: Water quality standards and...

  17. 30 CFR 816.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 816.42 Section 816.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-SURFACE MINING ACTIVITIES § 816.42 Hydrologic balance: Water quality standards and...

  18. 30 CFR 817.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 817.42 Section 817.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.42 Hydrologic balance: Water quality standards and...

  19. 30 CFR 817.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 817.42 Section 817.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.42 Hydrologic balance: Water quality standards and...

  20. 30 CFR 816.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 816.42 Section 816.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-SURFACE MINING ACTIVITIES § 816.42 Hydrologic balance: Water quality standards and...

  1. 30 CFR 817.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 817.42 Section 817.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.42 Hydrologic balance: Water quality standards and...

  2. 30 CFR 817.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 817.42 Section 817.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.42 Hydrologic balance: Water quality standards and...

  3. 30 CFR 816.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 816.42 Section 816.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-SURFACE MINING ACTIVITIES § 816.42 Hydrologic balance: Water quality standards and...

  4. 30 CFR 816.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 816.42 Section 816.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-SURFACE MINING ACTIVITIES § 816.42 Hydrologic balance: Water quality standards and...

  5. 30 CFR 817.42 - Hydrologic balance: Water quality standards and effluent limitations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Hydrologic balance: Water quality standards and effluent limitations. 817.42 Section 817.42 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND... STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.42 Hydrologic balance: Water quality standards and...

  6. Programs for generating data tables for the annual water-resources data report of the U.S. Geological Survey

    USGS Publications Warehouse

    Mason, R.R.; Hill, C.L.

    1988-01-01

    The U.S. Geological Survey has developed software that interfaces with the Automated Data Processing System to facilitate and expedite preparation of the annual water-resources data report. This software incorporates a feature that prepares daily values tables and appends them to previously edited files containing station manuscripts. Other features collate the merged files with miscellaneous sections of the report. The report is then printed as page-size, camera-ready copy. All system components reside on a minicomputer; this provides easy access and use by remote field offices. Automation of the annual report preparation process results in significant savings of labor and cost. Use of the system for producing the 1986 annual report in the North Carolina District realized a labor savings of over two man-months. A fully implemented system would produce a greater savings and speed release of the report to users.

  7. Will water scarcity in semiarid regions limit hydraulic fracturing of shale plays?

    NASA Astrophysics Data System (ADS)

    Scanlon, Bridget R.; Reedy, Robert C.; Nicot, Jean Philippe

    2014-12-01

    There is increasing concern about water constraints limiting oil and gas production using hydraulic fracturing (HF) in shale plays, particularly in semiarid regions and during droughts. Here we evaluate HF vulnerability by comparing HF water demand with supply in the semiarid Texas Eagle Ford play, the largest shale oil producer globally. Current HF water demand (18 billion gallons, bgal; 68 billion liters, bL in 2013) equates to ˜16% of total water consumption in the play area. Projected HF water demand of ˜330 bgal with ˜62 000 additional wells over the next 20 years equates to ˜10% of historic groundwater depletion from regional irrigation. Estimated potential freshwater supplies include ˜1000 bgal over 20 yr from recharge and ˜10 000 bgal from aquifer storage, with land-owner lease agreements often stipulating purchase of freshwater. However, pumpage has resulted in excessive drawdown locally with estimated declines of ˜100-200 ft in ˜6% of the western play area since HF began in 2009-2013. Non-freshwater sources include initial flowback water, which is ≤5% of HF water demand, limiting reuse/recycling. Operators report shifting to brackish groundwater with estimated groundwater storage of 80 000 bgal. Comparison with other semiarid plays indicates increasing brackish groundwater and produced water use in the Permian Basin and large surface water inputs from the Missouri River in the Bakken play. The variety of water sources in semiarid regions, with projected HF water demand representing ˜3% of fresh and ˜1% of brackish water storage in the Eagle Ford footprint indicates that, with appropriate management, water availability should not physically limit future shale energy production.

  8. Comprehensive cooling water study annual report. Volume VIII: semi-aquatic vertebrates, Savannah River Plant

    SciTech Connect

    Gladden, J.B.; Lower, M.W.; Mackey, H.E.; Specht, W.L.; Wilde, E.W.

    1985-07-01

    Several semi-aquatic vertebrate species are regularly observed in ''natural'' and ''post-thermal'' environments at SRP. Fewer species are regularly observed in thermally-altered areas. Yellow-bellied slider turtles, however, seem to thrive in areas of mildly elevated temperatures where they exhibit larger female body size than specimens from some ambient temperature areas of the SRP. Yellow-bellied slider turtles are the predominant species of semi-aquatic turtle on the SRP. Research conducted during 1984 was aimed toward examination of the activity levels of these animals, and their movement patterns within and among thermally- and nonthermally-altered wetlands on the SRP. Additional studies conducted on movement patterns of turtles in relation to reproduction examined emigration rates in five species of turtles during years of normal rainfall compared with a year of drought at a Carolina Bay. Studies of body size of slider turtles showed that animals inhabiting thermally-altered areas attain larger sizes than do individuals from ambient areas, presumably because the elevated temperatures allow for longer annual activity and feeding periods. Slider turtles from coastal, and from thermally- and nonthermally-altered inland populations, were examined for relationships between growth and clutch parameters. Slider turtles from an area of radioactive contamination were also studied for a determination of strontium-90 and cesium-137 bio-elimination. Studies of the brown water snake in the vicinity of Steel Creek and in the vicinity of Upper Three Runs Creek showed that these animals are primarily diurnal and prefer cool water temperatures. Preliminary sampling was initiated in 1984 to determine the structure of the Steel Creek snake community. 65 refs., 5 figs., 26 tabs.

  9. Dynamics of three types of annual plants competing for water and light

    NASA Astrophysics Data System (ADS)

    Pȩkalski, Andrzej; Szwabiński, Janusz

    2013-02-01

    We present and discuss a Monte Carlo model describing the dynamics of three types of annual plants which have different tolerances to shade and drought. External conditions (water and light) fluctuate around some values which are our control parameters and which decide how many resources the system receives. The plants compete with their nearest neighbours for the resources, however not in the same way. We show that for certain ranges of the control parameters a coexistence of the three species is observed. We discuss how the characteristics of the the plants - their number, germination, biomass or the number of nearest neighbours, depend on the two control parameters characterising external conditions. We show that elimination is done at the level of adult plants, not seedlings. We find also cooperative behaviour of plants in difficult conditions, as observed in field studies and we propose an explanation for this fact. Apart from plants tolerating shade but requiring more water and those tolerating drought but needing more light, which are common in nature, we introduce a third species with intermediary demands. We investigate under what conditions this new species could dominate and whether the total number of plants, regardless of their type, is larger with or without the intermediate plant. We show that in our model, like in nature, systems with two kinds of plants with opposite characteristics are, in general, as effective as a system with an additional third type of plants. We show that two contradictory hypotheses made by biologists, concerning the demands of plants in drought and shade, could be both true, however in different regimes.

  10. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mod...

  11. Photosynthetic limitations in response to water stress and recovery in Mediterranean plants with different growth forms.

    PubMed

    Galmés, Jeroni; Medrano, Hipólito; Flexas, Jaume

    2007-01-01

    * Whether photosynthesis is limited during water stress and recovery because of diffusive or biochemical factors is still open to debate, and apparent contradictions appear when various studies on species with different growth forms are compared. * Ten Mediterranean species, representing different growth forms, were subjected to different levels of water stress, the most severe followed by rewatering. A quantitative limitation analysis was applied to estimate the effects of water stress on stomatal (S(L)), mesophyll conductance (MC(L)) and biochemical limitations (B(L)). * Results confirmed a general pattern of photosynthetic response to water stress among C(3) plants when stomatal conductance (g(s)) is used as a reference parameter. As g(s) values decreased from a maximum to approx. 0.05 mol H(2)O m(-2) s(-1), the total photosynthetic limitation rose from 0 to approx. 70%, and this was caused by a progressive increase of both S(L) and MC(L) limitations, while B(L) remained negligible. When lower values of g(s) were achieved (total photosynthetic limitation increased from 70 to 100%), the contribution of S(L) declined, while MC(L) still increased and B(L) contributed significantly (20-50%) to the total limitation. * Photosynthetic recovery of severely stressed plants after rewatering showed a dominant role of MC(L), irrespective of the degree of photosynthesis recovery.

  12. Stocking of Offsite Waters for Hungry Horse Dam Mitigation Creston National Fish Hatchery, FY 2006 Annual Report.

    SciTech Connect

    Hooley, Sharon

    2009-03-20

    A total of 350,000, M012 strain, westslope cutthroat trout (WCT) eggs were received from Montana Fish Wildlife & Parks (MFWP), Washoe Park State Fish Hatchery in June of 2005 to accomplish this fishery management objective. These eggs were incubated, hatched and reared entirely inside the hatchery nursery building using a protected well water supply. Fish grew according to schedule and survival was excellent. The hatchery achieved a 0.78 feed fed to pounds gained conversion ratio for this group of WCT. Not all of the progenies from this fish lot were used for Hungry Horse Dam Fishery Mitigation Implementation. Some were used for other regional fishery management projects. Westslope cutthroat trout were reared using approved fish culture techniques as recommended in the USFWS Fish Hatchery Management Handbook and also utilizing a regimen adapted for hatchery specific site conditions. The fish health for these WCT was very good. Survival from first feeding fry stage to stocking was 79%. The hatchery had an annual fish health inspection performed by the USFWS Bozeman Fish Health Center in mid March of 2006. This inspection found all fish lots at Creston to be disease free. The Montana State Fish Health Board has placed the hatchery under a limited quarantine since May of 2005 due to an epizootic of Furunculosis. This classification has allowed the Creston NFH to stock disease free fish in locations approved by regional fish managers. The hatchery has been working with the State Fish Pathologist to remove the limited quarantine classification from the facility. Although fish health for all station fish lots remains disease free, MFWP has asserted it will not remove the limited quarantine until the new influent water treatment system, including the ultraviolet disinfection unit, is running full time, year round. The USFWS is working to secure the additional funding necessary to operate the treatment building year round. Distribution of the WCT took place from March

  13. Development of solid electrolytes for water electrolysis at intermediate temperatures. Task 3 report; Annual report

    SciTech Connect

    Linkous, C.A.; Anderson, R.; Kopitzke, R.W.

    1995-12-01

    This project is an attempt to synthesize and fabricate proton exchange membranes for hydrogen production via water electrolysis that can take advantage of the better kinetic and thermodynamic conditions that exist at higher temperatures. Current PEM technology is limited to the 125--150 C range. Based on previous work evaluating thermohydrolytic stability, some 5 families of polymers were chosen as viable candidates: polyether ketones, polyether sulfones, fluorinated polyimides, polybenzimidazoles, and polyphenyl quinoxalines. Several of these have been converted into ionomers via sulfonation and fashioned into membranes for evaluation. In particular, the sulfonated polyetheretherketone, or SPEEK, was tested for water uptake, thermo-conductimetric analysis, and performance as the solid electrolyte material in an electrolysis cell. Results comparable to commercial perfluorocarbon sulfonates were obtained.

  14. Regional annual water yield from forest lands and its response to potential deforestation across the southeastern United States

    NASA Astrophysics Data System (ADS)

    Sun, G.; McNulty, S. G.; Lu, J.; Amatya, D. M.; Liang, Y.; Kolka, R. K.

    2005-07-01

    Regional water yield at a meso-scale can be estimated as the difference between precipitation input and evapotranspiration output. Forest water yield from the southeastern US varies greatly both in space and time. Because of the hot climate and high evapotranspiration, less than half of the annual precipitation that falls on forest lands is available for stream flow in this water-rich region. Water yield is highest in the mountainous regions that receive the highest precipitation and have the lowest air temperature, and the lowest in the coastal regions that are dominated by wetlands receiving moderate rainfall but high evapotranspiration. Water resource management for both floods and droughts demands an accurate estimation of water yield from forests. Projected climate and land use changes further increase the variability of water yield in the region. The objectives of this study were to (1) develop a simple annual water yield modeling procedure by testing and calibrating a generalized global evapotranspiration model, (2) to apply the validated model to estimate regional forest water yield and to predict potential water yield response to forest removal. Hydrologic databases at a watershed-scale and a regional-scale were developed for model development, calibration, and validation. We applied the water yield model to the southern region by integrating land cover and high resolution climate databases by using a Geographic Information System (GIS). The model developed in this paper can be used to examine the spatial and temporal variability for water yield and predict the effects of climate and land cover changes at the regional scale.

  15. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    NASA Astrophysics Data System (ADS)

    Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

    2014-12-01

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess advantages over available alternatives, including: (i) the solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

  16. Aquifer-test results, direction of ground-water flow, and 1984-90 annual ground-water pumpage for irrigation, lower Big Lost River Valley, Idaho

    USGS Publications Warehouse

    Bassick, M.D.; Jones, M.L.

    1992-01-01

    The study area (see index map of Idaho), part of the Big Lost River drainage basin, is at the northern side of the eastern Snake River Plain. The lower Big Lost River Valley extends from the confluence of Antelope Creek and the Big Lost River to about 4 mi south of Arco and encompasses about 145 mi2 (see map showing water-level contours). The study area is about 18 mi long and, at its narrowest, 4 mi wide. Arco, Butte City, and Moore, with populations of 1,016, 59, and 190, respectively, in 1990, are the only incorporated towns. The entire study area, except the extreme northwestern part, is in Butte City. The study area boundary is where alluvium and colluvium pinch out and abut against the White Knob Mountains (chiefly undifferentiated sedimentary rock with lesser amounts of volcanic rock) on the west and the Lost River Range (chiefly sedimentary rock) on the east. Gravel and sand in the valley fill compose the main aquifer. The southern boundary is approximately where Big Lost River valley fill intercalates with or abuts against basalt of the Snake River Group. Spring ground-water levels and flow in the Big Lost River depend primarily on temperature and the amount and timing of precipitation within the entire drainage basin. Periods of abundant water supply and water shortages are, therefore, related to the amount of annual precipitation. Surface reservoir capacity in the valley (Mackay Reservoir, about 20 mi northwest of Moore) is only 20 percent of the average annual flow of the Big Lost River (Crosthwaite and others, 1970, p. 3). Stored surface water is generally unavailable for carryover from years of abundant water supply to help relieve drought conditions in subsequent years. Many farmers have drilled irrigation wells to supplement surface-water supplies and to increase irrigated acreage. Average annual flow of the Big Lost River below Mackay Reservoir near Mackay (gaging station 13127000, not shown) in water years 1905, 1913-14, and 1920-90 was about 224

  17. Limited effectiveness of household sand filters for removal of arsenic from well water in North Vietnam.

    PubMed

    Ilmiawati, Cimi; Thang, Nguyen Dinh; Iida, Machiko; Maeda, Masao; Ohnuma, Shoko; Yajima, Ichiro; Ohgami, Nobutaka; Oshino, Reina; Al Hossain, M M Aeorangajeb; Ninomiya, Hiromasa; Kato, Masashi

    2016-12-01

    Since well water utilized for domestic purposes in the Red River Delta of North Vietnam has been reported to be polluted by arsenic, barium, iron, and manganese, household sand filters consisting of various components are used. Information regarding the effectiveness of various sand filters for removal of the four toxic elements in well water is limited. In this study, arsenic levels in 13/20 of well water samples and 1/7 of tap water samples exceeded World Health Organization (WHO) health-based guideline value for drinking water. Moreover, 2/20, 6/20, and 4/20 of well water samples had levels exceeding the present and previous guideline levels for barium, iron, and manganese, respectively. Levels of iron and manganese, but not arsenic, in well water treated by sand filters were lower than those in untreated water, although previous studies showed that sand filters removed all of those elements from water. A low ratio of iron/arsenic in well water may not be sufficient for efficient removal of arsenic from household sand filters. The levels of barium in well water treated by sand filters, especially a filter composed of sand and charcoal, were significantly lower than those in untreated water. Thus, we demonstrated characteristics of sand filters in North Vietnam.

  18. Energy and Water Fluxes in Heterogeneous Mediterranean Water-limited Ecosystems

    NASA Astrophysics Data System (ADS)

    Detto, M.; Katul, G.; Mancini, M.

    2005-12-01

    Research efforts in distributed eco-hydrologic models often fall in one of two categories: prognostic, in which predictions of root-zone soil moisture content and land surface fluxes is required for a projected radiative and precipitation forcing time series, or diagnostic in which the relationship between soil water status and atmospheric water vapor demand is to be derived for the various components of the landscape. The latter relationships are now receiving broad attention in climate change, hydrological, and ecological studies of arid and semi-arid ecosystems. This interest is now a central focus given the recognition that the component latent heat flux sensitivity to soil moisture decline can directly impact plant productivity, carbon and nutrient cycling, and ground water recharge. With projected shifts in precipitation statistics, mainly towards increased desertification, the "stability" of these ecosystems is highly dependent on their ability to uptake water at low soil moisture Here, we determine the relationship between soil water status and atmospheric water vapor demand for patchy landscapes within a semi-arid ecosystems using a combination remote sensing products and field experiments. In particular, we investigate how VIS/NIR measurements, in conjunction with standard micrometeorological data and ground based thermal infrared thermometers, provide "diagnostic" hydrologic relationship between soil water content and potential evapo-transpiration for the various components of the landscape. These experiments were conducted in the Orroli site, situated in the mid-west of Sardinia (Italy) within the Flumendosa river watershed, which is considered one of the most important water supply resources to the island. The landscape is a mixture of Mediterranean patchy vegetation types: trees, including wild olives (/Olea sylvestris/) and cork oaks (/Quercus suber/), different shrubs (/Asparagus acutifolius, Rubus ulmifolius/) and herbaceous species (/Asphodelus

  19. Evaluation of Management of Water Release for Painted Rocks Reservoir, Bitterroot River, Montana, 1984 Annual Report.

    SciTech Connect

    Lere, Mark E.

    1984-11-01

    Baseline fisheries and habitat data were gathered during 1983 and 1984 to evaluate the effectiveness of supplemental water releases from Painted Rocks Reservoir in improving the fisheries resource in the Bitterroot River. Discharge relationships among main stem gaging stations varied annually and seasonally. Flow relationships in the river were dependent upon rainfall events and the timing and duration of the irrigation season. Daily discharge monitored during the summers of 1983 and 1984 was greater than median values derived at the U.S.G.S. station near Darby. Supplemental water released from Painted Rocks Reservoir totaled 14,476 acre feet in 1983 and 13,958 acre feet in 1984. Approximately 63% of a 5.66 m{sup 3}/sec test release of supplemental water conducted during April, 1984 was lost to irrigation withdrawals and natural phenomena before passing Bell Crossing. A similar loss occurred during a 5.66 m{sup 3}/sec test release conducted in August, 1984. Daily maximum temperature monitored during 1984 in the Bitterroot River averaged 11.0, 12.5, 13.9 and 13.6 C at the Darby, Hamilton, Bell and McClay stations, respectively. Chemical parameters measured in the Bitterroot River were favorable to aquatic life. Population estimates conducted in the Fall, 1983 indicated densities of I+ and older rainbow trout (Salmo gairdneri) were significantly greater in a control section than in a dewatered section (p < 0.20). Numbers of I+ and older brown trout (Salmo trutta) were not significantly different between the control and dewatered sections (p > 0.20). Population and biomass estimates for trout in the control section were 631/km and 154.4 kg/km. In the dewatered section, population and biomass estimates for trout were 253/km and 122.8 kg/km. The growth increments of back-calculated length for rainbow trout averaged 75.6 mm in the control section and 66.9mm in the dewatered section. The growth increments of back-calculated length for brown trout averaged 79.5 mm in the

  20. Optimal demand reponse to water pricing policies under limited water supply in irrigation: a case study

    NASA Astrophysics Data System (ADS)

    Grießbach, Ulkrike; Stange, Peter; Schuetze, Niels

    2015-04-01

    Due to climate change, extreme weather conditions such as droughts may have an increasing impact on irrigated agriculture. To cope with the higher demand of water, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand. For modeling the regional water demand, local stochastic water demand functions are used which are derived from optimized agronomic response on farms scale. These functions take into account different soil types, crops, stochastically generated climate scenarios considering different economic conditions, e.g., variable and fixed costs. This generic approach enables the consideration of both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance IRrigation) project a prototype of a decision support system is developed and applied for a case study in Saxony which helps to evaluate combined water supply and demand management policies on a regional level.

  1. Vegetation Dynamics and Soil Water Balance Interactions in a Water-limited Mediterranean Ecosystem on Sardinia Under Climate Change Scenarios

    NASA Astrophysics Data System (ADS)

    Montaldo, N.; Albertson, J. D.

    2009-12-01

    Mediterranean ecosystems are commonly heterogeneous savanna-like ecosystems, with contrasting plant functional types (PFT) competing for the water use. At the same time the structure and function of the vegetation regulates the exchange of mass, energy and momentum across the biosphere-atmosphere interface, influencing strongly the soil water budget. Mediterranean regions suffer water scarcity produced in part by natural (e.g., climate variations) influences. For instance, in the Flumendosa basin water reservoir system, which plays a primary role in the water supply for much of southern Sardinia, the average annual input from stream discharge in the latter part of the 20th century was less than half the historic average rate. The precipitation over the Flumendosa basin has decreased, but not at such a drastic rate as the discharge, suggesting a marked non-linear response of discharge to precipitation changes. Indeed, precipitation decreased in winter months, which are crucial for reservoirs recharge through runoff. The IPCC models predicts a further increase of drought in the Mediterranean region, increasing the uncertainty on the future of the water resources system of these regions. Hence, there is the need to investigate the role of the PFT vegetation dynamics on the soil water budget of these ecosystems in the context of the climate change, and predict hydrologic variables for climate change scenarios. The case study is in the Flumendosa basin. The site landscape is a mixture of Mediterranean patchy vegetation types: trees, including wild olives and cork oaks, different shrubs and herbaceous species. An extensive field campaign started in May 2003. Six years of data are available now. Land-surface fluxes and CO2 fluxes are estimated by an eddy correlation technique based micrometeorological tower. Soil moisture profiles were also continuously estimated using water content reflectometers and gravimetric method, and periodically leaf area index (LAI) PFTs are

  2. Soil Water Balance and Vegetation Dynamics in a Water-limited Mediterranean Ecosystem on Sardinia under climate change scenarios

    NASA Astrophysics Data System (ADS)

    Montaldo, Nicola; Cortis, Clorinda; Albertson, John D.

    2010-05-01

    Mediterranean ecosystems are commonly heterogeneous savanna-like ecosystems, with contrasting plant functional types (PFT) competing for the water use. At the same time the structure and function of the vegetation regulates the exchange of mass, energy and momentum across the biosphere-atmosphere interface, influencing strongly the soil water budget. Mediterranean regions suffer water scarcity produced in part by natural (e.g., climate variations) influences. For instance, in the Flumendosa basin water reservoir system, which plays a primary role in the water supply for much of southern Sardinia, the average annual input from stream discharge in the latter part of the 20th century was less than half the historic average rate. The precipitation over the Flumendosa basin has decreased, but not at such a drastic rate as the discharge, suggesting a marked non-linear response of discharge to precipitation changes. Indeed, precipitation decreased in winter months, which are crucial for reservoirs recharge through runoff. The IPCC models predicts a further increase of drought in the Mediterranean region, increasing the uncertainty on the future of the water resources system of these regions. Hence, there is the need to investigate the role of the PFT vegetation dynamics on the soil water budget of these ecosystems in the context of the climate change, and predict hydrologic variables for climate change scenarios. The case study is in the Flumendosa basin. The site landscape is a mixture of Mediterranean patchy vegetation types: trees, including wild olives and cork oaks, different shrubs and herbaceous species. An extensive field campaign started in May 2003. More than six years of data of a micrometeorological tower are available now. Land-surface fluxes and CO2 fluxes are estimated by the eddy correlation technique based micrometeorological tower. Soil moisture profiles were also continuously estimated using water content reflectometers and gravimetric method, and

  3. 40 CFR 130.7 - Total maximum daily loads (TMDL) and individual water quality-based effluent limitations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... individual water quality-based effluent limitations. 130.7 Section 130.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.7 Total maximum daily loads (TMDL) and individual water quality-based effluent limitations. (a) General....

  4. 40 CFR 130.7 - Total maximum daily loads (TMDL) and individual water quality-based effluent limitations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... individual water quality-based effluent limitations. 130.7 Section 130.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.7 Total maximum daily loads (TMDL) and individual water quality-based effluent limitations. (a) General....

  5. 40 CFR 130.7 - Total maximum daily loads (TMDL) and individual water quality-based effluent limitations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... individual water quality-based effluent limitations. 130.7 Section 130.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.7 Total maximum daily loads (TMDL) and individual water quality-based effluent limitations. (a) General....

  6. 40 CFR 130.7 - Total maximum daily loads (TMDL) and individual water quality-based effluent limitations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... individual water quality-based effluent limitations. 130.7 Section 130.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.7 Total maximum daily loads (TMDL) and individual water quality-based effluent limitations. (a) General....

  7. 40 CFR 130.7 - Total maximum daily loads (TMDL) and individual water quality-based effluent limitations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... individual water quality-based effluent limitations. 130.7 Section 130.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.7 Total maximum daily loads (TMDL) and individual water quality-based effluent limitations. (a) General....

  8. Regression Method for Estimating Long-Term Mean Annual Ground-Water Recharge Rates from Base Flow in Pennsylvania

    USGS Publications Warehouse

    Risser, Dennis W.; Thompson, Ronald E.; Stuckey, Marla H.

    2008-01-01

    A method was developed for making estimates of long-term, mean annual ground-water recharge from streamflow data at 80 streamflow-gaging stations in Pennsylvania. The method relates mean annual base-flow yield derived from the streamflow data (as a proxy for recharge) to the climatic, geologic, hydrologic, and physiographic characteristics of the basins (basin characteristics) by use of a regression equation. Base-flow yield is the base flow of a stream divided by the drainage area of the basin, expressed in inches of water basinwide. Mean annual base-flow yield was computed for the period of available streamflow record at continuous streamflow-gaging stations by use of the computer program PART, which separates base flow from direct runoff on the streamflow hydrograph. Base flow provides a reasonable estimate of recharge for basins where streamflow is mostly unaffected by upstream regulation, diversion, or mining. Twenty-eight basin characteristics were included in the exploratory regression analysis as possible predictors of base-flow yield. Basin characteristics found to be statistically significant predictors of mean annual base-flow yield during 1971-2000 at the 95-percent confidence level were (1) mean annual precipitation, (2) average maximum daily temperature, (3) percentage of sand in the soil, (4) percentage of carbonate bedrock in the basin, and (5) stream channel slope. The equation for predicting recharge was developed using ordinary least-squares regression. The standard error of prediction for the equation on log-transformed data was 9.7 percent, and the coefficient of determination was 0.80. The equation can be used to predict long-term, mean annual recharge rates for ungaged basins, providing that the explanatory basin characteristics can be determined and that the underlying assumption is accepted that base-flow yield derived from PART is a reasonable estimate of ground-water recharge rates. For example, application of the equation for 370

  9. Least Limiting Water Range of soils in the Colonia Agrícola de Turen, Venezuela

    NASA Astrophysics Data System (ADS)

    Perez, Maiby Yolanda; Florentino de Andreu, Adriana

    2013-04-01

    Soil physical degradation is a major problem affecting the soil quality for crops production in Venezuelan agricultural areas. The least limiting water range (LLWR) is considered a soil physical quality index defined as the range in soil water content within which the limitations to plant response associated with water potential, poor aeration and high mechanical resistance are minimal. The study was carried out to characterize the LLWR and to determine the LLWR response to structural changes on soils of the Colonia Agricola de Turen, Venezuela. The soils were cropped with maize under different tillage systems (no tillage, conventional and conventional - fallow) and non-cropped under native forest. Hundred and seventy undisturbed samples were taken from specific sites under each of the above soil conditions to determine the water retention curve, the soil resistance curve and bulk density. Disturbed samples were also taken from each site to determine particle size and organic matter content. Pedotransfer functions relating the water retention curve and soil resistance curve with particle size distribution, organic matter content and bulk density were developed and use to calculate the LLWR for each site. According to the results, soil physical degradation under conventional tillage and high clay content had the highest negative impact on the LLWR. For this case (silty clay loam soil), the LLWR became narrower due to the lower water content associated with poor aeration and the higher water content associated with high mechanical resistance. In contrast, for non degraded soils with high sand content (sandy loam) the LLWR showed the highest values associated with the water content at field capacity and the water content at permanent wilting point, both the upper and lower critical limits of LLWR. For silty loam and loam soils the LLWR declined with increasing bulk density and clay content associated with water content at field capacity and water content at high

  10. Effects of Alder Mine on the Water, Sediments, and Benthic Macroinvertebrates of Alder Creek, 1998 Annual Report.

    SciTech Connect

    Peplow, Dan

    1999-05-28

    The Alder Mine, an abandoned gold, silver, copper, and zinc mine in Okanogan County, Washington, produces heavy metal-laden effluent that affects the quality of water in a tributary of the Methow River. The annual mass loading of heavy metals from two audits at the Alder Mine was estimated to exceed 11,000 kg per year. In this study, water samples from stations along Alder Creek were assayed for heavy metals by ICP-AES and were found to exceed Washington State's acute freshwater criteria for cadmium (Cd), copper (Cu), selenium (Se), and zinc (Zn).

  11. Inter- and intra-annual variation of water footprint of crops and blue water scarcity in the Yellow River basin (1961-2009)

    NASA Astrophysics Data System (ADS)

    Zhuo, La; Mekonnen, Mesfin M.; Hoekstra, Arjen Y.; Wada, Yoshihide

    2016-01-01

    The Yellow River Basin (YRB), the second largest river basin of China, has experienced a booming agriculture over the past decades. But data on variability of and trends in water consumption, pollution and scarcity in the YRB are lacking. We estimate, for the first time, the inter- and intra-annual water footprint (WF) of crop production in the YRB for the period 1961-2009 and the variation of monthly scarcity of blue water (ground and surface water) for 1978-2009, by comparing the blue WF of agriculture, industry and households in the basin to the maximum sustainable level. Results show that the average overall green (from rainfall) and blue (from irrigation) WFs of crops in the period 2001-2009 were 14% and 37% larger, respectively, than in the period 1961-1970. The annual nitrogen- and phosphorus-related grey WFs (water required to assimilate pollutants) of crop production grew by factors of 24 and 36, respectively. The green-blue WF per ton of crop reduced significantly due to improved crop yields, while the grey WF increased because of the growing application of fertilizers. The ratio of blue to green WF increased during the study period resulting from the expansion of irrigated agriculture. In the period 1978-2009, the annual total blue WFs related to agriculture, industry and households varied between 19% and 52% of the basin's natural runoff. The blue WF in the YRB generally peaks around May-July, two months earlier than natural peak runoff. On average, the YRB faced moderate to severe blue water scarcity during seven months (January-July) per year. Even in the wettest month in a wet year, about half of the area of the YRB still suffered severe blue water scarcity, especially in the basin's northern part.

  12. Scaling-up leaf monoterpene emissions from a water limited Quercus ilex woodland

    NASA Astrophysics Data System (ADS)

    Lavoir, A. V.; Duffet, C.; Mouillot, F.; Rambal, S.; Ratte, J. P.; Schnitzler, J. P.; Staudt, M.

    2011-06-01

    Mediterranean ecosystems are large emitters of biogenic volatile organic compounds (BVOC), and recent studies illustrate how water stress can decrease these emissions even during hot summer. We present here a spatially explicit modelling experiment of BVOC emissions in a water-limited Mediterranean Region in Southern France dominated by Quercus ilex forests. Emission rates were estimated daily using a leaf-level emission model with appropriate up-scaling procedures. The model was based on Guenther's empirical equations, where we inserted effects for water limitation and seasonality observed from field measurements. Up-scaling from leaves to canopy was performed using Sellers' theory. For each grid cell, climate variables were interpolated daily from meteorological stations. Incoming solar radiation was measured at one site and extrapolated for the all region based on slope and aspect. Soil properties were derived from pedological maps as well as a digital elevation model, while soil water content was evaluated daily using a bucket-type model. We estimated monoterpene emissions from Q. ilex woodlands to be 16 kt yr -1 (on average), with most emissions occurring in the summer. When including the water-limitation module, yearly emissions were 50% of the initial estimates, with a significant decrease in the number of days with BVOC high emission peaks. This result highlights the importance of water control on determining air pollution peaks in Mediterranean areas and the need for scaling procedure in this area with its large range of strong emitter species.

  13. A partition-limited model for the plant uptake of organic contaminants from soil and water

    USGS Publications Warehouse

    Chiou, C.T.; Sheng, G.; Manes, M.

    2001-01-01

    In dealing with the passive transport of organic contaminants from soils to plants (including crops), a partition-limited model is proposed in which (i) the maximum (equilibrium) concentration of a contaminant in any location in the plant is determined by partition equilibrium with its concentration in the soil interstitial water, which in turn is determined essentially by the concentration in the soil organic matter (SOM) and (ii) the extent of approach to partition equilibrium, as measured by the ratio of the contaminant concentrations in plant water and soil interstitial water, ??pt (??? 1), depends on the transport rate of the contaminant in soil water into the plant and the volume of soil water solution that is required for the plant contaminant level to reach equilibrium with the external soil-water phase. Through reasonable estimates of plant organic-water compositions and of contaminant partition coefficients with various plant components, the model accounts for calculated values of ??pt in several published crop-contamination studies, including near-equilibrium values (i.e., ??pt ??? 1) for relatively water-soluble contaminants and lower values for much less soluble contaminants; the differences are attributed to the much higher partition coefficients of the less soluble compounds between plant lipids and plant water, which necessitates much larger volumes of the plant water transport for achieving the equilibrium capacities. The model analysis indicates that for plants with high water contents the plant-water phase acts as the major reservoir for highly water-soluble contaminants. By contrast, the lipid in a plant, even at small amounts, is usually the major reservoir for highly water-insoluble contaminants.

  14. Uncertainty analysis of a spatially explicit annual water-balance model: case study of the Cape Fear basin, North Carolina

    NASA Astrophysics Data System (ADS)

    Hamel, P.; Guswa, A. J.

    2015-02-01

    There is an increasing demand for assessment of water provisioning ecosystem services. While simple models with low data and expertise requirements are attractive, their use as decision-aid tools should be supported by uncertainty characterization. We assessed the performance of the InVEST annual water yield model, a popular tool for ecosystem service assessment based on the Budyko hydrological framework. Our study involved the comparison of 10 subcatchments ranging in size and land-use configuration, in the Cape Fear basin, North Carolina. We analyzed the model sensitivity to climate variables and input parameters, and the structural error associated with the use of the Budyko framework, a lumped (catchment-scale) model theory, in a spatially explicit way. Comparison of model predictions with observations and with the lumped model predictions confirmed that the InVEST model is able to represent differences in land uses and therefore in the spatial distribution of water provisioning services. Our results emphasize the effect of climate input errors, especially annual precipitation, and errors in the ecohydrological parameter Z, which are both comparable to the model structure uncertainties. Our case study supports the use of the model for predicting land-use change effect on water provisioning, although its use for identifying areas of high water yield will be influenced by precipitation errors. While some results are context-specific, our study provides general insights and methods to help identify the regions and decision contexts where the model predictions may be used with confidence.

  15. Environmental and socioeconomic benefits and limitations of water harvesting techniques in semiarid regions

    NASA Astrophysics Data System (ADS)

    Díaz-Pereira, Elvira; Asunción Romero-Díaz, María; de Vente, Joris

    2016-04-01

    Under climate change, sustainable management of soil and water resources is increasingly important, especially in rainfed agroecosystems of semiarid environments. Water harvesting refers to a range of techniques for the collection and management of flood or rainwater for domestic and agricultural use and for water retention in natural ecosystems. Water harvesting represents a good example of sustainable management of water resources that contribute to water and food security. However, there are often environmental and socioeconomic constraints for implementation of water harvesting techniques, so each condition asks for a specific solution. Here we aim to highlight the environmental and socioeconomic benefits, requirements and limitations of different water harvesting techniques and to characterize their implications for provisioning, regulating, supporting, and cultural ecosystem services. We reviewed 62 water harvesting techniques for semiarid regions extracted from the WOCAT (World Overview of Conservation Approaches and Technologies) database. We discuss aspects related to: i) human and environmental characteristics, ii) cost-benefit ratio during implementation and maintenance phases, iii) socioeconomic and environmental impacts at local and regional scales, and, iv) impacts on ecosystem services. Our review reveals that water harvesting represents very diverse methods of collecting and managing floodwaters and surface runoff. We grouped techniques as 'floodwater harvesting', 'macro-catchment water harvesting', 'micro-catchment water harvesting', and 'rooftop and courtyard' water harvesting. Almost half of all technologies originates from traditional knowledge. The implementation of water harvesting is generally positive on the short-term, to very positive on the long-term, while its maintenance is very positive at short and long-term. However, perception depends on the type of water harvesting and local conditions. Most relevant socioeconomic benefits from

  16. Effects of water addition on soil arthropods and soil characteristics in a precipitation-limited environment

    NASA Astrophysics Data System (ADS)

    Chikoski, Jennifer M.; Ferguson, Steven H.; Meyer, Lense

    2006-09-01

    We investigated the effect of water addition and season on soil arthropod abundance and soil characteristics (%C, %N, C:N, moisture, pH). The experimental design consisted of 24 groups of five boxes distributed within a small aspen stand in Saskatchewan, Canada. The boxes depressed the soil to create a habitat with suitable microclimate for soil arthropods, and by overturning boxes we counted soil arthropods during weekly surveys from April to September 1999. Soil samples were collected at two-month intervals and water was added once per week to half of the plots. Of the eleven recognizable taxonomic units identified, only mites (Acari) and springtails (Collembola) responded to water addition by increasing abundance, whereas ants decreased in abundance with water addition. During summer, springtail numbers increased with water addition, whereas pH was a stronger determinant of mite abundance. In autumn, springtails were positively correlated with water and negatively correlated with mites, whereas mite abundance was negatively correlated with increasing C:N ratio, positively correlated to water addition, and negatively correlated with springtail abundance. Although both mite and springtail numbers decreased in autumn with a decrease in soil moisture, mites became more abundant than springtails suggesting a predator-prey (mite-springtail) relationship. Water had a significant effect on both springtails and mites in summer and autumn supporting the assertion that prairie soil communities are water limited.

  17. Ballast water regulations and the move toward concentration-based numeric discharge limits.

    PubMed

    Albert, Ryan J; Lishman, John M; Saxena, Juhi R

    2013-03-01

    Ballast water from shipping is a principal source for the introduction of nonindigenous species. As a result, numerous government bodies have adopted various ballast water management practices and discharge standards to slow or eliminate the future introduction and dispersal of these nonindigenous species. For researchers studying ballast water issues, understanding the regulatory framework is helpful to define the scope of research needed by policy makers to develop effective regulations. However, for most scientists, this information is difficult to obtain because it is outside the standard scientific literature and often difficult to interpret. This paper provides a brief review of the regulatory framework directed toward scientists studying ballast water and aquatic invasive species issues. We describe different approaches to ballast water management in international, U.S. federal and state, and domestic ballast water regulation. Specifically, we discuss standards established by the International Maritime Organization (IMO), the U.S. Coast Guard and U.S. Environmental Protection Agency, and individual states in the United States including California, New York, and Minnesota. Additionally, outside the United States, countries such as Australia, Canada, and New Zealand have well-established domestic ballast water regulatory regimes. Different approaches to regulation have recently resulted in variations between numeric concentration-based ballast water discharge limits, particularly in the United States, as well as reliance on use of ballast water exchange pending development and adoption of rigorous science-based discharge standards. To date, numeric concentration-based discharge limits have not generally been based upon a thorough application of risk-assessment methodologies. Regulators, making decisions based on the available information and methodologies before them, have consequently established varying standards, or not established standards at all. The

  18. Addressing water scarcity through limited irrigation cropping: Field experiments and modeling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Population growth in urbanizing areas such as the Front Range of Colorado has led to increased pressure to transfer water from agriculture to municipalities. In many cases this has led to complete dry up of productive irrigated lands. An option to complete dry-up is the practice of limited or defi...

  19. Sunflower response to irrigation from limited water supplies with no-till management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Limited irrigation necessitates maximizing economic returns by rotating crops, so we conducted a field study during 2005-2009 in southwest Kansas to determine the yield response of sunflower to irrigation and evapotranspiration (ETc) and to measure plant growth parameters and soil water use. Sunflow...

  20. Parsimonious modeling of vegetation dynamics for ecohydrologic studies of water-limited ecosystems

    NASA Astrophysics Data System (ADS)

    Montaldo, Nicola; Rondena, Roberta; Albertson, John D.; Mancini, Marco

    2005-10-01

    The structure and function of vegetation regulate fluxes across the biosphere-atmosphere interface with large effects in water-limited ecosystems. Vegetation dynamics are often neglected in hydrological modeling except for simple prescriptions of seasonal phenology. However, changes in vegetation densities, influencing the partitioning of incoming solar energy into sensible and latent heat fluxes, can result in long-term changes in both local and global climates with resulting feedbacks on vegetation growth. This paper seeks a simple vegetation dynamics model (VDM) for simulation of the leaf area index (LAI) dynamics in hydrologic models. Five variants of a VDM are employed, with a range of model complexities. The VDMs are coupled to a land surface model (LSM), with the VDM providing the LAI evolution through time and the LSM using this to compute the land surface fluxes and update the soil water contents. We explore the models through case studies of water-limited grass fields in California (United States) and North Carolina (United States). Results show that a simple VDM, simulating only the living aboveground green biomass (i.e., with low parameterization), is able to accurately simulate the LAI. Results also highlight the importance of including the VDM in the LSM when studying the climate-soil-vegetation interactions over moderate to long timescales. The inclusion of the VDM in the LSM is demonstrated to be essential for assessing the impact of interannual rainfall variability on the water budget of a water limited region.

  1. The Dynamic of Annual Carbon Allocation to Wood in European Forests Is Consistent with a Combined Source-Sink Limitation of Growth: Implications on Growth Simulations in a Terrestrial Biosphere Model

    NASA Astrophysics Data System (ADS)

    Guillemot, J.; Martin-StPaul, N. K.; Dufrêne, E.; François, C.; Soudani, K.; Ourcival, J. M.; Leadley, P.; Delpierre, N.

    2014-12-01

    The extent to which forest growth is limited by carbon (C) supply (source control) or by cambial activity (sink control) will strongly determines the responses of trees to global changes. However, the physiological processes responsible for the limitation of forest growth are still under debate. The aim of this study was i) to evaluate the key drivers of the annual carbon allocation to wood along large soil and climate regional gradients in four tree species representative of the main European forest biomes (Fagus sylvatica, Quercus petraea, Quercus ilex and Picea abies) ii) to implement the identified key drivers in a new C allocation scheme within the CASTANEA terrestrial biosphere model (TBM). Combining field measurements and process-based simulations at 49 sites (931 site-years), our analyses revealed that the inter-site variability in C allocation to wood was predominantly driven by an age-related decline. The direct control of temperature or water stress on sink activity (i.e. independently from their effects on C supply) exerted a strong influence on the annual woody growth in all the species considered, including deciduous temperate species. The lagged effect of the past environment conditions was a significant driver of the annual C allocation to wood. Carbon supply appeared to strongly limit growth only in deciduous temperate species. Our study supports the premise that European forest growth is under a complex panel of source- and sink- limitations, contradicting the simple source control implemented in most TBMs. The implementation of these combined forest growth limitations in the CASTANEA model significantly improved its performance when evaluated against independent stand growth data at the regional scale (mainland France, >103 plots). We finally discuss how the sink imitation affects the CASTANEA simulated projections of forest productivity along the 21th century, especially with respect to the expected fertilizing effect of increasing atmospheric

  2. Greenhouse gas emissions of drained fen peatlands in Belarus are controlled by water table, land use, and annual weather conditions

    NASA Astrophysics Data System (ADS)

    Burlo, Andrei; Minke, Merten; Chuvashova, Hanna; Augustin, Jürgen; Hoffmann, Mathias; Narkevitch, Ivan

    2014-05-01

    Drainage of peatlands causes strong emission of the greenhouse gases (GHG) CO2 and N2O, sometimes combined with a weak CH4 uptake. In Belarus drained peatlands occupy about 1505000 ha or more than 7.2 % of the country area. Joosten (2009) estimates CO2 emission from degraded peatlands in Belarus as 41.3 Mt yr-1 what equals to 47 % of total anthropogenic greenhouse gases (GHGs) emission of country in 2011. However, it could not be checked if these numbers are correct since there are no GHG measurements on these sites up to now. Therefore we studied the GHG emissions with the closed chamber approach in four peatlands situated in central and southern Belarus over a period from August 2010 to August 2012. The measurements comprised eight site types representing different water level conditions, and ranging from grassland and arable land over abandoned fields and peat cuts to near-natural sedge fens. Fluxes of CH4 and N2O were determined using the close-chamber approach every second week in snow free periods and every fourth week during winter time. The annual emissions were calculated based on linear interpolation. Carbon dioxide exchange was measured with transparent and opaque chambers every 3-4 weeks and the annual net ecosystem exchange (NEE) was modeled according to Drösler (2005). Most of the drained sites were sources of CO2 in both years. NEE increased with lower mean annual water table level. The highest NEE value (1263.5 g CO2-C m-1yr-1) was observed at the driest site of the study; an abandoned fen formerly used for agriculture. In contrast, a former peat extraction site with moist peat and small Pinus sylvestris tress were sinks of CO2 with uptake to 389.6 g CO2-C m-1yr-1. The highest N2O emissions were recorded at a drained agricultural fen with mean annual rates of up to 2347 mg N2O-N m-2 yr-1. Significant fluxes of CH4 (15 g CH4C m-2 h-1) were observed only at the near-natural site in the first year of investigation when precipitation and the mean water

  3. Planning water supply under uncertainty - benefits and limitations of RDM, Info-Gap, economic optimization and many-objective optimization

    NASA Astrophysics Data System (ADS)

    Matrosov, E.; Padula, S.; Huskova, I.; Harou, J. J.

    2012-12-01

    Population growth and the threat of drier or changed climates are likely to increase water scarcity world-wide. A combination of demand management (water conservation) and new supply infrastructure is often needed to meet future projected demands. In this case system planners must decide what to implement, when and at what capacity. Choices can range from infrastructure to policies or a mix of the two, culminating in a complex planning problem. Decision making under uncertainty frameworks can be used to help planners with this planning problem. This presentation introduces, applies and compares four decision making under uncertainty frameworks. The application is to the Thames basin water resource system which includes the city of London. The approaches covered here include least-economic cost capacity expansion optimization (EO), Robust Decision Making (RDM), Info-Gap Decision Theory (Info-gap) and many-objective evolutionary optimization (MOEO). EO searches for the least-economic cost program, i.e. the timing, sizing, and choice of supply-demand management actions/upgrades which meet projected water demands. Instead of striving for optimality, the RDM and Info-gap approaches help build plans that are robust to 'deep' uncertainty in future conditions. The MOEO framework considers multiple performance criteria and uses water systems simulators as a function evaluator for the evolutionary algorithm. Visualizations show Pareto approximate tradeoffs between multiple objectives. In this presentation we detail the application of each framework to the Thames basin (including London) water resource planning problem. Supply and demand options are proposed by the major water companies in the basin. We apply the EO method using a 29 year time horizon and an annual time step considering capital, operating (fixed and variable), social and environmental costs. The method considers all plausible combinations of supply and conservation schemes and capacities proposed by water

  4. Stay-green traits to improve wheat adaptation in well-watered and water-limited environments

    PubMed Central

    Christopher, John.T.; Christopher, Mandy J.; Borrell, Andrew K.; Fletcher, Susan; Chenu, Karine

    2016-01-01

    A stay-green phenotype enables crops to retain green leaves longer after anthesis compared with senescent types, potentially improving yield. Measuring the normalized difference vegetative index (NDVI) during the whole senescence period allows quantification of component stay-green traits contributing to a stay-green phenotype. These objective and standardized traits can be compared across genotypes and environments. Traits examined include maximum NDVI near anthesis (Nmax), senescence rate (SR), a trait integrating senescence (SGint), plus time from anthesis to onset (OnS), mid-point (MidS), and near completion (EndS) of senescence. The correlation between stay-green traits and yield was studied in eight contrasting environments ranging from well watered to severely water limited. Environments were each classified into one of the four major drought environment types (ETs) previously identified for the Australian wheat cropping system. SGint, OnS, and MidS tended to have higher values in higher yielding environments for a given genotype, as well as for higher yielding genotypes within a given environment. Correlation between specific stay-green traits and yield varied with ET. In the studied population, SGint, OnS, and MidS strongly correlated with yield in three of the four ETs which included well-watered environments (0.43–0.86), but less so in environments with only moderate water-stress after anthesis (−0.03 to 0.31). In contrast, Nmax was most highly correlated with yield under moderate post-anthesis water stress (0.31–0.43). Selection for particular stay-green traits, combinations of traits, and/or molecular markers associated with the traits could enhance genetic progress toward stay-green wheats with higher, more stable yield in both well-watered and water-limited conditions. PMID:27443279

  5. Stay-green traits to improve wheat adaptation in well-watered and water-limited environments.

    PubMed

    Christopher, John T; Christopher, Mandy J; Borrell, Andrew K; Fletcher, Susan; Chenu, Karine

    2016-09-01

    A stay-green phenotype enables crops to retain green leaves longer after anthesis compared with senescent types, potentially improving yield. Measuring the normalized difference vegetative index (NDVI) during the whole senescence period allows quantification of component stay-green traits contributing to a stay-green phenotype. These objective and standardized traits can be compared across genotypes and environments. Traits examined include maximum NDVI near anthesis (Nmax), senescence rate (SR), a trait integrating senescence (SGint), plus time from anthesis to onset (OnS), mid-point (MidS), and near completion (EndS) of senescence. The correlation between stay-green traits and yield was studied in eight contrasting environments ranging from well watered to severely water limited. Environments were each classified into one of the four major drought environment types (ETs) previously identified for the Australian wheat cropping system. SGint, OnS, and MidS tended to have higher values in higher yielding environments for a given genotype, as well as for higher yielding genotypes within a given environment. Correlation between specific stay-green traits and yield varied with ET. In the studied population, SGint, OnS, and MidS strongly correlated with yield in three of the four ETs which included well-watered environments (0.43-0.86), but less so in environments with only moderate water-stress after anthesis (-0.03 to 0.31). In contrast, Nmax was most highly correlated with yield under moderate post-anthesis water stress (0.31-0.43). Selection for particular stay-green traits, combinations of traits, and/or molecular markers associated with the traits could enhance genetic progress toward stay-green wheats with higher, more stable yield in both well-watered and water-limited conditions.

  6. 76 FR 59373 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Generic Annual Catch Limits...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ...) for Reef Fish Resources, Red Drum, Shrimp, and Coral and Coral Reefs for the Gulf of Mexico (Gulf) for... Coral and Coral Reefs FMP. The majority of harvest of octocorals occurs in waters under the...

  7. Summary of annual mean and annual harmonic mean statistics of daily mean streamflow for 620 U.S. Geological Survey streamflow-gaging stations in Texas through water year 2007

    USGS Publications Warehouse

    Asquith, William H.; Heitmuller, Franklin T.

    2008-01-01

    Analysts and managers of surface-water resources have interest in annual mean and annual harmonic mean statistics of daily mean streamflow for U.S. Geological Survey (USGS) streamflow-gaging stations in Texas. The mean streamflow represents streamflow volume, whereas the harmonic mean streamflow represents an appropriate statistic for assessing constituent concentrations that might adversely affect human health. In 2008, the USGS, in cooperation with the Texas Commission on Environmental Quality, conducted a large-scale documentation of mean and harmonic mean streamflow for 620 active and inactive, continuous-record, streamflow-gaging stations using period of record data through water year 2007. About 99 stations within the Texas USGS streamflow-gaging network are part of the larger national Hydroclimatic Data Network and are identified. The graphical depictions of annual mean and annual harmonic mean statistics in this report provide a historical perspective of streamflow at each station. Each figure consists of three time-series plots, two flow-duration curves, and a statistical summary of the mean annual and annual harmonic mean streamflow statistics for available data for each station.The first time-series plot depicts daily mean streamflow for the period 1900-2007. Flow-duration curves follow and are a graphical depiction of streamflow variability. Next, the remaining two time-series plots depict annual mean and annual harmonic mean streamflow and are augmented with horizontal lines that depict mean and harmonic mean for the period of record. Monotonic trends for the annual mean streamflow and annual harmonic mean streamflow also are identified using Kendall's tau, and the slope of the trend is depicted using the nonparametric (linear) Theil-Sen line, which is only drawn for p-values less than .10 of tau. The history of annual mean and annual harmonic mean streamflow of one or more streamflow-gaging stations could be used in a watershed, river basin, or other

  8. Spatial distribution and intra-annual variability of water masses on the Eastern Gulf of Cadiz seabed

    NASA Astrophysics Data System (ADS)

    Bellanco, M. J.; Sánchez-Leal, R. F.

    2016-10-01

    This paper presents the spatial distribution and intra-annual variability of seabed hydrography in the Eastern Gulf of Cadiz based on more than 10 years of near-bottom CTD observations. Well-defined water masses and a variety of mixing products are persistently sorted along three bathymetric areas occupying particular depth intervals: (i) inner shelf waters (<60 m depth), with strong coastal and atmospheric influence; (ii) low-salinity Eastern North Atlantic Central Waters (ENACW), related to the Gulf of Cadiz Current (GCC) along the central and outer shelf (between 100 and 250 m depth); and (iii) a range of salinity and temperature flavors associated with the dense Mediterranean Outflow Water (MOW) occupying the deeper grounds. All three are characterized by significant March-November hydrographic differences suggesting an intra-annual variability pattern. After summer heating and stratification of the water column, warm (17.8 °C) and saline (36.26) waters occupy the inner-shelf in November whereas cooler (14.6 °C) and less saline (36.17) waters occur in March as the combined result of the erosion of the seasonal thermocline and intensified continental runoff. Offshore, colder, more saline and hence denser MOW invades the upper slope in March diluting the easternmost tip of a saltier ENACW wedge and nudging its outer rim up onto the shelf. This narrows and constricts the GCC band in winter, while its bottom trace appears to broaden and stretch eastwards in November. More effective MOW-ENACW mixing west of the Strait of Gibraltar driven both by an elevated MOW and a less stratified ENACW could explain the winter salinification of most of the grounds deeper than 250 m.

  9. A discussion paper on challenges and limitations to water reuse and hygiene in the food industry.

    PubMed

    Casani, Sandra; Rouhany, Mahbod; Knøchel, Susanne

    2005-03-01

    Drinking water is becoming a scarce resource in many areas and both use of water and wastewater outlet are of major ecological and economical importance in many countries. Consumption and discharge may be considerably minimized by means of water reuse. The food industry has a large consumption of water, but until now very limited reuse has taken place due to legislations constraints and hygienic concerns. Legal space for use of water of qualities other than drinking water has been opened with the current legislation. This will, however, in many cases require careful analyses of individual cases based on a thorough understanding of the hazards involved in order to avoid compromising the safety of the food product and thereby the health of consumers. Implementation of water reuse practices in the food industry presents a great challenge for both companies and public health authorities regarding knowledge, technical expertise and documentation. Regulatory, technological, monitoring, verification and ethical aspects associated with microbiologically safe reuse of water in the food industry are discussed and some examples of the challenges ahead and possible approaches are given.

  10. Does water chemistry limit the distribution of New Zealand mud snails in Redwood National Park?

    USGS Publications Warehouse

    Vazquez, Ryan; Ward, Darren M.; Sepulveda, Adam

    2016-01-01

    New Zealand mud snails (NZMS) are exotic mollusks present in many waterways of the western United States. In 2009, NZMS were detected in Redwood Creek in Redwood National Park, CA. Although NZMS are noted for their ability to rapidly increase in abundance and colonize new areas, after more than 5 years in Redwood Creek, their distribution remains limited to a ca. 300 m reach. Recent literature suggests that low specific conductivity and environmental calcium can limit NZMS distribution. We conducted laboratory experiments, exposing NZMS collected from Redwood Creek to both natural waters and artificial treatment solutions, to determine if low conductivity and calcium concentration limit the distribution of NZMS in Redwood National Park. For natural water exposures, we held NZMS in water from their source location (conductivity 135 μS/cm, calcium 13 mg/L) or water from four other locations in the Redwood Creek watershed encompassing a range of conductivity (77–158 μS/cm) and calcium concentration (<5–13 mg/L). For exposures in treatment solutions, we manipulated both conductivity (range 20–200 μS/cm) and calcium concentration (range <5–17.5 mg/L) in a factorial design. Response variables measured included mortality and reproductive output. Adult NZMS survived for long periods (>4 months) in the lowest conductivity waters from Redwood Creek and all but the lowest-conductivity treatment solutions, regardless of calcium concentration. However, reproductive output was very low in all natural waters and all low-calcium treatment solutions. Our results suggest that water chemistry may inhibit the spread of NZMS in Redwood National Park by reducing their reproductive output.

  11. Glycerol enhances fungal germination at the water-activity limit for life.

    PubMed

    Stevenson, Andrew; Hamill, Philip G; Medina, Ángel; Kminek, Gerhard; Rummel, John D; Dijksterhuis, Jan; Timson, David J; Magan, Naresh; Leong, Su-Lin L; Hallsworth, John E

    2017-03-01

    For the most-extreme fungal xerophiles, metabolic activity and cell division typically halts between 0.700 and 0.640 water activity (approximately 70.0-64.0% relative humidity). Here, we investigate whether glycerol can enhance xerophile germination under acute water-activity regimes, using an experimental system which represents the biophysical limit of Earth's biosphere. Spores from a variety of species, including Aspergillus penicillioides, Eurotium halophilicum, Xerochrysium xerophilum (formerly Chrysosporium xerophilum) and Xeromyces bisporus, were produced by cultures growing on media supplemented with glycerol (and contained up to 189 mg glycerol g dry spores(-1) ). The ability of these spores to germinate, and the kinetics of germination, were then determined on a range of media designed to recreate stresses experienced in microbial habitats or anthropogenic systems (with water-activities from 0.765 to 0.575). For A. penicillioides, Eurotium amstelodami, E. halophilicum, X. xerophilum and X. bisporus, germination occurred at lower water-activities than previously recorded (0.640, 0.685, 0.651, 0.664 and 0.637 respectively). In addition, the kinetics of germination at low water-activities were substantially faster than those reported previously. Extrapolations indicated theoretical water-activity minima below these values; as low as 0.570 for A. penicillioides and X. bisporus. Glycerol is present at high concentrations (up to molar levels) in many types of microbial habitat. We discuss the likely role of glycerol in expanding the water-activity limit for microbial cell function in relation to temporal constraints and location of the microbial cell or habitat. The findings reported here have also critical implications for understanding the extremes of Earth's biosphere; for understanding the potency of disease-causing microorganisms; and in biotechnologies that operate at the limits of microbial function.

  12. Water resource data for North Carolina, water year 1993. Volume 1. Surface-water records. Water-data report (Annual), 1 October 1992-30 September 1993

    SciTech Connect

    Barker, R.G.; George, E.D.; Rinehardt, J.F.; Eddins, W.H.

    1994-03-25

    Water resources data for the 1993 water year for North Carolina consist of records of stage, discharge, and water quality of streams; and stage and contents of lakes and reservoirs. The report contains discharge records for 159 gaging stations and stage and contents for 56 lakes and reservoirs; water quality for 54 gaging stations and 5 miscellaneous sites; and continuous daily tide stage for 10 sites. Additional water data were collected at 69 sites not involved in the systematic data-collection program and are published as miscellaneous measurements in the report.

  13. The Climate change impact on the water balance and use efficiency of two contrasting water limited Mediterranean ecosystems in Sardinia

    NASA Astrophysics Data System (ADS)

    Montaldo, Nicola; Corona, Roberto; Albertson, John

    2016-04-01

    Mediterranean ecosystems are commonly heterogeneous savanna-like ecosystems, with contrasting plant functional types (PFT) competing for the water use. Often deforestation activities have been more intensive along the plan and alluvial river valleys, where deep soils are well suited for agricultural and grass became the primary PFT, while more natural woody vegetation (trees and shrubs) survived in the steep hillslopes and mountain areas, where soil thickness is low, i.e. less attractive for agricultural. Hence, Mediterranean regions are characterized by two main ecosystems, grassland and woodland, which for both natural and anthropogenic causes can grow in soils with also different characteristics (texture, hydraulic properties, depth), highly impacting water resources. Mediterranean regions suffer water scarcity produced in part by natural (e.g., climate variations) influences. For instance, in the Flumendosa basin water reservoir system, which plays a primary role in the water supply for much of southern Sardinia, the average annual input from stream discharge in the latter part of the 20th century was less than half the historic average rate. The precipitation over the Flumendosa basin has decreased, but not at such a drastic rate as the discharge, suggesting a marked non-linear response of discharge to precipitation changes. Indeed, precipitation decreased in winter months, which are crucial for reservoirs recharge through runoff. At the same time air temperature increased during the spring-summer season, when the precipitation slightly increased. The IPCC models predicts a further increase of drought in the Mediterranean region during winter, increasing the uncertainty on the future of the water resources system of these regions. Hence, there is the need to investigate the role of the PFT vegetation dynamics on the soil water budget of these ecosystems in the context of the climate change, and predict hydrologic variables for climate change scenarios

  14. Contribution of water-limited ecoregions to their own supply of rainfall

    NASA Astrophysics Data System (ADS)

    Miralles, Diego G.; Nieto, Raquel; McDowell, Nathan G.; Dorigo, Wouter A.; Verhoest, Niko EC; Liu, Yi Y.; Teuling, Adriaan J.; Dolman, A. Johannes; Good, Stephen P.; Gimeno, Luis

    2016-12-01

    The occurrence of wet and dry growing seasons in water-limited regions remains poorly understood, partly due to the complex role that these regions play in the genesis of their own rainfall. This limits the predictability of global carbon and water budgets, and hinders the regional management of natural resources. Using novel satellite observations and atmospheric trajectory modelling, we unravel the origin and immediate drivers of growing-season precipitation, and the extent to which ecoregions themselves contribute to their own supply of rainfall. Results show that persistent anomalies in growing-season precipitation—and subsequent biomass anomalies—are caused by a complex interplay of land and ocean evaporation, air circulation and local atmospheric stability changes. For regions such as the Kalahari and Australia, the volumes of moisture recycling decline in dry years, providing a positive feedback that intensifies dry conditions. However, recycling ratios increase up to 40%, pointing to the crucial role of these regions in generating their own supply of rainfall; transpiration in periods of water stress allows vegetation to partly offset the decrease in regional precipitation. Findings highlight the need to adequately represent vegetation-atmosphere feedbacks in models to predict biomass changes and to simulate the fate of water-limited regions in our warming climate.

  15. Climatic correlates of tree mortality in water- and energy-limited forests

    USGS Publications Warehouse

    Das, Adrian J.; Stephenson, Nathan L.; Flint, Alan; Das, Tapash; van Mantgem, Phillip J.

    2013-01-01

    Recent increases in tree mortality rates across the western USA are correlated with increasing temperatures, but mechanisms remain unresolved. Specifically, increasing mortality could predominantly be a consequence of temperature-induced increases in either (1) drought stress, or (2) the effectiveness of tree-killing insects and pathogens. Using long-term data from California’s Sierra Nevada mountain range, we found that in water-limited (low-elevation) forests mortality was unambiguously best modeled by climatic water deficit, consistent with the first mechanism. In energy-limited (high-elevation) forests deficit models were only equivocally better than temperature models, suggesting that the second mechanism is increasingly important in these forests. We could not distinguish between models predicting mortality using absolute versus relative changes in water deficit, and these two model types led to different forecasts of mortality vulnerability under future climate scenarios. Our results provide evidence for differing climatic controls of tree mortality in water- and energy-limited forests, while highlighting the need for an improved understanding of tree mortality processes.

  16. Climatic correlates of tree mortality in water- and energy-limited forests.

    PubMed

    Das, Adrian J; Stephenson, Nathan L; Flint, Alan; Das, Tapash; van Mantgem, Phillip J

    2013-01-01

    Recent increases in tree mortality rates across the western USA are correlated with increasing temperatures, but mechanisms remain unresolved. Specifically, increasing mortality could predominantly be a consequence of temperature-induced increases in either (1) drought stress, or (2) the effectiveness of tree-killing insects and pathogens. Using long-term data from California's Sierra Nevada mountain range, we found that in water-limited (low-elevation) forests mortality was unambiguously best modeled by climatic water deficit, consistent with the first mechanism. In energy-limited (high-elevation) forests deficit models were only equivocally better than temperature models, suggesting that the second mechanism is increasingly important in these forests. We could not distinguish between models predicting mortality using absolute versus relative changes in water deficit, and these two model types led to different forecasts of mortality vulnerability under future climate scenarios. Our results provide evidence for differing climatic controls of tree mortality in water- and energy-limited forests, while highlighting the need for an improved understanding of tree mortality processes.

  17. Climatic Correlates of Tree Mortality in Water- and Energy-Limited Forests

    PubMed Central

    Das, Adrian J.; Stephenson, Nathan L.; Flint, Alan; Das, Tapash; van Mantgem, Phillip J.

    2013-01-01

    Recent increases in tree mortality rates across the western USA are correlated with increasing temperatures, but mechanisms remain unresolved. Specifically, increasing mortality could predominantly be a consequence of temperature-induced increases in either (1) drought stress, or (2) the effectiveness of tree-killing insects and pathogens. Using long-term data from California’s Sierra Nevada mountain range, we found that in water-limited (low-elevation) forests mortality was unambiguously best modeled by climatic water deficit, consistent with the first mechanism. In energy-limited (high-elevation) forests deficit models were only equivocally better than temperature models, suggesting that the second mechanism is increasingly important in these forests. We could not distinguish between models predicting mortality using absolute versus relative changes in water deficit, and these two model types led to different forecasts of mortality vulnerability under future climate scenarios. Our results provide evidence for differing climatic controls of tree mortality in water- and energy-limited forests, while highlighting the need for an improved understanding of tree mortality processes. PMID:23936118

  18. UK catchment nutrient loads 1993-2003, a new approach using harmonised monitoring scheme data: temporal changes, geographical distribution, limiting nutrients and loads to coastal waters.

    PubMed

    Earl, Timothy J; Upton, Graham J G; Nedwell, David B

    2014-07-01

    The work provides robust estimates of nutrient loads (nitrate and phosphate) from all UK catchments: as required by the Water Framework Directive to monitor catchments' health, and to inform management of these environments. To calculate nutrient loads, data for nutrient concentrations and water flow are combined. In the UK, flow data are typically available at hourly intervals at more than 1300 gauging stations but concentration data are collected less frequently (roughly weekly) and at fewer locations (about 280). The sparseness of the concentration data limits the occasions for which load can be calculated, so a mathematical model was derived which was used to interpolate the concentrations between measurements. The model's parameters provide useful information about the annual nutrient concentration cycles within any catchment, and permitted improved estimates of both the annual loads of N and P, and of the N : P ratios, from mainland UK catchments. Data from 1993-2003 showed nitrate loads from UK catchments were generally constant, while orthophosphate loads generally declined. N : P ratios suggested that most catchments in the north and west of the UK were potentially P-limited although a few were potentially N-limited, while many in central and eastern UK oscillated seasonally between N and P limitation. Knowledge of the nutrient which is potentially limiting to biological productivity is a key factor for management of a catchment's nutrient loads. Calculations of nutrient export loads to coastal regions showed that UK catchments contributed only about 16.5% of total fluvial loads of nitrate to the North Sea, or about 3% of the total N loads when inputs from the Atlantic were included. Orthophosphate loads from the UK catchments into the North Sea were only 1.7% of the total P inputs from rivers and the Atlantic but did not include riverine inputs of P adsorbed to particles.

  19. Comprehensive cooling water study annual report. Volume X: endangered species, Savannah River Plant

    SciTech Connect

    Gladden, J.B.; Lower, M.W.; Mackey, H.E.; Specht, W.L.; Wilde, E.W.

    1985-07-01

    Federally endangered species which occur on the Savannah River Plant (SRP) include the American alligator, red-cockaded woodpecker, the shortnose sturgeon, and the wood stork. Of these species, only the alligator, sturgeon, and wood stork are likely to be affected by the intake or release of cooling water at the SRP. The nearest colony of wood storks to the SRP is the Birdsville Colony, about 40-45 km southwest of potential foraging areas in the SRP Savannah River swamp. In 1983, it contained about six percent of the nesting pairs in the United States and produced about 250 fledglings. Its reproductive success was about the same in 1984. Based on the results of surveys made of foraging areas, both on SRP and offsite in 1983 and 1984, forage fish availability could be reduced by increased water depths in the Steel Creek delta area following L-Reactor restart with once-through cooling. Effluent discharge from SRP facilities probably limits the potential use of the SRP Savannah River swamp by foraging wood storks. The SRP supports a low-to-moderate alligator population. The current information available on the alligators of the SRP suggests that populations in suitable habitats (e.g., Beaver Dam Creek, Steel Creek, and Par Pond) should continue to benefit from the protection provided by the SRP and should remain stable or continue to increase. Based upon information from the literature and fisheries data for the Savannah River, the operations of the SRP do not appear to have adverse effects on the shortnose sturgeon. Based on known life history characteristics, there is no indication that spawning, rearing, or foraging habitats are affected by SRP operations. 64 refs., 20 figs., 12 tabs.

  20. Drought impact on water use efficiency and intra-annual density fluctuations in Erica arborea on Elba (Italy).

    PubMed

    Battipaglia, Giovanna; DE Micco, Veronica; Brand, Willi A; Saurer, Matthias; Aronne, Giovanna; Linke, Petra; Cherubini, Paolo

    2014-02-01

    Erica arborea (L) is a widespread Mediterranean species, able to cope with water stress and colonize semiarid environments. The eco-physiological plasticity of this species was evaluated by studying plants growing at two sites with different soil moistures on the island of Elba (Italy), through dendrochronological, wood-anatomical analyses and stable isotopes measurements. Intra-annual density fluctuations (IADFs) were abundant in tree rings, and were identified as the key parameter to understand site-specific plant responses to water stress. Our findings showed that the formation of IADFs is mainly related to the high temperature, precipitation patterns and probably to soil water availability, which differs at the selected study sites. The recorded increase in the (13) C-derived intrinsic water use efficiency at the IADFs level was linked to reduced water loss rather than to increasing C assimilation. The variation in vessel size and the different absolute values of δ(18) O among trees growing at the two study sites underlined possible differences in stomatal control of water loss and possible differences in sources of water uptake. This approach not only helped monitor seasonal environmental differences through tree-ring width, but also added valuable information on E. arborea responses to drought and their ecological implications for Mediterranean vegetation dynamics.

  1. Physiological strategies of co-occurring oaks in a water- and nutrient-limited ecosystem.

    PubMed

    Renninger, Heidi J; Carlo, Nicholas; Clark, Kenneth L; Schäfer, Karina V R

    2014-02-01

    Oak species are well suited to water-limited conditions by either avoiding water stress through deep rooting or tolerating water stress through tight stomatal control. In co-occurring species where resources are limited, species may either partition resources in space and/or time or exhibit differing efficiencies in the use of limited resources. Therefore, this study seeks to determine whether two co-occurring oak species (Quercus prinus L. and Quercus velutina Lam.) differ in physiological parameters including photosynthesis, stomatal conductance, water-use (WUE) and nitrogen-use efficiency (NUE), as well as to characterize transpiration and average canopy stomatal responses to climatic variables in a sandy, well-drained and nutrient-limited ecosystem. The study was conducted in the New Jersey Pinelands and we measured sap flux over a 3-year period, as well as leaf gas exchange, leaf nitrogen and carbon isotope concentrations. Both oak species showed relatively steep increases in leaf-specific transpiration at low vapor pressure deficit (VPD) values before maximum transpiration rates were achieved, which were sustained over a broad range in VPD. This suggests tight stomatal control over transpiration in both species, although Q. velutina showed significantly higher leaf-level and canopy-level stomatal conductance than Q. prinus. Average daytime stomatal conductance was positively correlated with soil moisture and both oak species maintained at least 75% of their maximum canopy stomatal conductance at soil moistures in the upper soil layer (0-0.3 m) as low as 0.03 m(3) m(3)(-3). Quercus velutina had significantly higher photosynthetic rates, maximum Rubisco-limited and electron-transport-limited carboxylation rates, dark respiration rates and nitrogen concentration per unit leaf area than Q. prinus. However, both species exhibited similar WUEs and NUEs. Therefore, Q. prinus has a more conservative resource-use strategy, while Q. velutina may need to exploit niches

  2. Increasing demands on limited water resources: Consequences for two endangered plants in Amargosa Valley, USA.

    PubMed

    Hasselquist, Niles J; Allen, Michael F

    2009-03-01

    Recent population expansion throughout the Southwest United States has created an unprecedented demand for already limited water resources, which may have severe consequences on the persistence of some species. Two such species are the federally protected Nitrophila mohavensis (Chenopodiaceae) and Grindelia fraxino-pratensis (Asteraceae) found in Amargosa Valley, one valley east of Death Valley, California. Because both species are federally protected, no plant material could be harvested for analysis. We therefore used a chamber system to collect transpired water for isotopic analysis. After a correction for isotopic enrichment during transpiration, δ(18)O values of plant xylem water were significantly different between N. mohavensis and G. fraxino-pratensis throughout the study. Using a multisource mixing model, we found that both N. mohavensis and G. fraxino-pratensis used soil moisture near the soil surface in early spring when surface water was present. However, during the dry summer months, G. fraxino-pratensis tracked soil moisture to deeper depths, whereas N. mohavensis continued to use soil moisture near the soil surface. These results indicate that pumping groundwater and subsequently lowering the water table may directly prevent G. fraxino-pratensis from accessing water, whereas these same conditions may indirectly affect N. mohavensis by reducing surface soil moisture and thus its ability to access water.

  3. Dispersal Limitations on Fish Community Recovery Following Long-term Water Quality Remediation

    SciTech Connect

    McManamay, Ryan A.; Jett, Robert T.; Ryon, Michael G.; Gregory, Scott M.; Stratton, Sally H.; Peterson, Mark J.

    2016-02-22

    Holistic restoration approaches, such as water quality remediation, are likely to meet conservation objectives because they are typically implemented at watershed scales, as opposed to individual stream reaches. However, habitat fragmentation may impose constraints on the ecological effectiveness of holistic restoration strategies by limiting colonization following remediation. We questioned the importance of dispersal limitations to fish community recovery following long-term water quality remediation and species reintroductions across the White Oak Creek (WOC) watershed near Oak Ridge, Tennessee (USA). Long-term (26 years) responses in fish species richness and biomass to water quality remediation were evaluated in light of habitat fragmentation and population isolation from instream barriers, which varied in their passage potential. In addition, ordination techniques were used to determine the relative importance of habitat connectivity and water quality, in explaining variation fish communities relative to environmental fluctuations, i.e. streamflow. Ecological recovery (changes in richness) at each site was negatively related to barrier index, a measure of community isolation by barriers relative to stream distance. Following species reintroductions, dispersal by fish species was consistently in the downstream direction and upstream passage above barriers was non-existent. The importance of barrier index in explaining variation in fish communities was stronger during higher flow conditions, but decreased over time an indication of increasing community stability and loss of seasonal migrants. Compared to habitat fragmentation, existing water quality concerns (i.e., outfalls, point source discharges) were unrelated to ecological recovery, but explained relatively high variation in community dynamics. Our results suggest that habitat fragmentation limited the ecological effectiveness of intensive water quality remediation efforts and fish reintroduction efforts

  4. Dispersal Limitations on Fish Community Recovery Following Long-term Water Quality Remediation

    DOE PAGES

    McManamay, Ryan A.; Jett, Robert T.; Ryon, Michael G.; ...

    2016-02-22

    Holistic restoration approaches, such as water quality remediation, are likely to meet conservation objectives because they are typically implemented at watershed scales, as opposed to individual stream reaches. However, habitat fragmentation may impose constraints on the ecological effectiveness of holistic restoration strategies by limiting colonization following remediation. We questioned the importance of dispersal limitations to fish community recovery following long-term water quality remediation and species reintroductions across the White Oak Creek (WOC) watershed near Oak Ridge, Tennessee (USA). Long-term (26 years) responses in fish species richness and biomass to water quality remediation were evaluated in light of habitat fragmentation andmore » population isolation from instream barriers, which varied in their passage potential. In addition, ordination techniques were used to determine the relative importance of habitat connectivity and water quality, in explaining variation fish communities relative to environmental fluctuations, i.e. streamflow. Ecological recovery (changes in richness) at each site was negatively related to barrier index, a measure of community isolation by barriers relative to stream distance. Following species reintroductions, dispersal by fish species was consistently in the downstream direction and upstream passage above barriers was non-existent. The importance of barrier index in explaining variation in fish communities was stronger during higher flow conditions, but decreased over time an indication of increasing community stability and loss of seasonal migrants. Compared to habitat fragmentation, existing water quality concerns (i.e., outfalls, point source discharges) were unrelated to ecological recovery, but explained relatively high variation in community dynamics. Our results suggest that habitat fragmentation limited the ecological effectiveness of intensive water quality remediation efforts and fish reintroduction

  5. Modeling analysis of ground water recharge potential on alluvial fans using limited data.

    PubMed

    Munévar, A; Mariño, M A

    1999-01-01

    A modeling approach is developed to evaluate the potential for artificial recharge on alluvial fans in the Salinas Valley, California, using limited data of soil texture, soil hydraulic properties, and interwell stratigraphy. Promising areas for surface recharge are identified and mapped on a broad-scale using soil surveys, geologic investigations, permeability tests, and seasonal ground water response to rainfall and runoff. Two-dimensional representations of the vadose zone at selected sites are then constructed from drillers'logs and soil material types are estimated. Next, hydraulic properties are assigned to each soil material type by comparing them to laboratory-tested cores of similar soils taken from one site. Finally, water flow through the vadose zone is modeled in two dimensions at seven sites using a transient, finite-difference, variably saturated flow model. Average infiltration rates range from 0.84 to 1.54 cm/hr and recharge efficiency, the percentage of infiltrated water that reaches the water table, varies from 51% to 79%. Infiltration rates and recharge efficiency are found to be relatively insensitive to recharge basin ponding depth due to the thickness of the vadose zones modeled (31 to 84 m). The impact of artificial recharge on the Salinas Valley ground water basin is investigated by simulating the regional ground water response to surface spreading and streamflow augmentation with a recently calibrated, finite-element, ground water-surface water model for the basin. It was determined that a combined approach of surface recharge and streamflow augmentation significantly reduces the state of ground water overdraft and, to a lesser extent, reduces the rate of sea water intrusion.

  6. The need for a reassessment of the safe upper limit of selenium in drinking water.

    PubMed

    Vinceti, Marco; Crespi, Catherine M; Bonvicini, Francesca; Malagoli, Carlotta; Ferrante, Margherita; Marmiroli, Sandra; Stranges, Saverio

    2013-01-15

    Results of recent epidemiologic studies suggest the need to reassess the safe upper limit in drinking water of selenium, a metalloid with both toxicological and nutritional properties. Observational and experimental human studies on health effects of organic selenium compounds consumed through diet or supplements, and of inorganic selenium consumed through drinking water, have shown that human toxicity may occur at much lower levels than previously surmised. Evidence indicates that the chemical form of selenium strongly influences its toxicity, and that its biological activity may differ in different species, emphasizing the importance of the few human studies on health effects of the specific selenium compounds found in drinking water. Epidemiologic studies that investigated the effects of selenate, an inorganic selenium species commonly found in drinking water, together with evidence of toxicity of inorganic selenium at low levels in from in vitro and animal studies, indicate that health risks may occur at exposures below the current European Union and World Health Organization upper limit and guideline of 10 and 40 μg/l, respectively, and suggest reduction to 1 μg/l in order to adequately protect human health. Although few drinking waters are currently known to have selenium concentrations exceeding this level, the public health importance of this issue should not be overlooked, and further epidemiologic research is critically needed in this area.

  7. Plant transpiration and groundwater dynamics in water-limited climates: Impacts of hydraulic redistribution

    NASA Astrophysics Data System (ADS)

    Luo, Xiangyu; Liang, Xu; Lin, Jeen-Shang

    2016-06-01

    The role of groundwater in sustaining plant transpiration constitutes an important but not well-understood aspect of the interactions between groundwater, vegetation, the land surface, and the atmosphere. The effect of the hydraulic redistribution (HR) process by plant roots on the interplay between plant transpiration and groundwater dynamics under water-limited climates is investigated by using the Variable Infiltration Capacity Plus (VIC+) land surface model. Numerical experiments, with or without explicitly considering HR, are conducted on soil columns over a range of groundwater table depths (GWTDs) under different vegetative land covers, soil types, and precipitation conditions. When HR is not included, this study obtains transpiration-GWTD relationships consistent with those from watershed studies that do not include HR. When HR is included, the transpiration-GWTD relationships are modified. The modification introduced by HR is manifested in the soil moisture of the root zone. The mechanism of HR is explained by detailing the roles of the hydraulically redistributed water, the upward diffusion of soil water, and the daytime root uptake. We have found that HR is particularly important in water-limited climates under which plants have high transpiration demand. At the beginning stage of a dry period, HR modulates the severe impacts that climate has on plant transpiration. Only after a prolonged dry period, impacts of HR are lessened when the groundwater table drops below the depth of water uptake by roots and are diminished when plant transpiration is decoupled from groundwater dynamics.

  8. Stoichiometry, Metabolism and Nutrient Limitation Across the Periodic Table in Natural Flowing-Water Chemostats

    NASA Astrophysics Data System (ADS)

    Cohen, M. J.; Nifong, R. L.; Kurz, M. J.; Cropper, W. P.; Martin, J. B.

    2014-12-01

    Relative supplies of macro and micronutrients (C,N,P, various metals), along with light and water, controls ecosystem metabolism, trophic energy transfer and community structure. Here we test the hypothesis, using measurements from 41 spring-fed rivers in Florida, that tissue stoichiometry indicates autotroph nutrient limitation status. Low variation in discharge, temperature and chemical composition within springs, but large variation across springs creates an ideal setting to assess the relationship between limitation and resource supply. Molar N:P ranges from 0.4 to 90, subjecting autotrophs to dramatically different nutrient supply. Over this gradient, species-specific autotroph tissue C:N:P ratios are strictly homeostatic, and with no evidence that nutrient supply affects species composition. Expanding to include 19 metals and micronutrients revealed autotrophs are more plastic in response to micronutrient variation, particularly for iron and manganese whose supply fluxes are small compared to biotic demand. Using a Droop model modified to reflect springs conditions (benthic production, light limitation, high hydraulic turnover), we show that tissue stoichiometry transitions from homeostatic to plastic with the onset of nutrient limitation, providing a potentially powerful new tool for predicting nutrient limitation and thus eutrophication in flowing waters.

  9. 76 FR 82264 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Comprehensive Annual Catch Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ... Atlantic Region (Snapper- Grouper FMP), the Golden Crab Fishery of the South Atlantic Region, the Dolphin... FMPs for Snapper-Grouper, Dolphin and Wahoo, Golden Crab, and Sargassum; revise the snapper-grouper... dolphin from for-hire vessels; and set a minimum size limit for dolphin off most of the South...

  10. Experimental limits on the proton life-time from the neutrino experiments with heavy water

    NASA Astrophysics Data System (ADS)

    Tretyak, V. I.; Zdesenko, Y. G.

    2001-04-01

    Experimental data on the number of neutrons born in the heavy water targets of the large neutrino detectors are used to set the limit on the proton life-time independently on decay mode through the reaction d-->n+?. The best up-to-date limit τp>4×1023 yr with 95% C.L. is derived from the measurements with D2O target (mass 267 kg) installed near the Bugey reactor. This value can be improved by six orders of magnitude with future data accumulated with the SNO detector containing 1000 t of D2O.

  11. Solid-state chemistry of photoelectrodes for water photoelectrolysis. Annual report, August 1983-September 1984

    SciTech Connect

    Eror, N.G.

    1984-10-01

    The author previously reported that donor-doped TiO2 and SrTiO3 have different defect structures that seem to be related to their differences in photoresponse. SrTiO3 exhibited bandgap reduction while TiO2 did not. A perovskite analogue, SrZrO3, without variable-valent cations was studied to elucidate the different mechanisms of donor-dopant compensation and photoresponse. The solubility limit of lanthanum was established and the defect structures of both pure and donor-doped SrZrO3 were determined. Electrical conductivity, thermogravimetric, chemical and interdiffusion, and Raman-spectroscopic measurements were used to determine the electronic and ionic defect compensation mechanisms. Both the composition and the crystal structure of heterogeneous catalysts are important in determining their activity, efficiency and specificity. The anatase polymorph of TiO2 is critical for efficient photolysis of water and the irreversible transformation to rutile occurs at relatively modest temperatures. They have used Raman spectroscopy to determine that rutile can be stabilized at temperatures below 450 C. The phase transformation from anatase to rutile was shown to be a function of both impurity type and concentration as well as ambient oxygen activity.

  12. The hydrological effects of varying vegetation characteristics in a temperate water-limited basin: Development of the dynamic Budyko-Choudhury-Porporato (dBCP) model

    NASA Astrophysics Data System (ADS)

    Liu, Qiang; McVicar, Tim R.; Yang, Zhifeng; Donohue, Randall J.; Liang, Liqiao; Yang, Yuting

    2016-12-01

    Vegetation patterns are affected by water availability, which, in turn, influences the hydrological partitioning and regional water balance, especially in water-limited regions. Considering the important role of vegetation in partitioning the catchment water yield, the recently developed Budyko-Choudhury-Porporato (or BCP) model incorporated Porporato's model of key ecohydrological processes into Choudury's form of the Budyko hydroclimatic framework. Here we extend the steady state BCP model by incorporating dynamic ecohydrological processes into it and combining it with a typical bucket soil water balance model (resulting in the dynamic BCP, or dBCP, model). The dBCP model is used here to assess the impacts of vegetation on the water balance in a temperate water-limited basin (i.e., the Yellow River Basin (YRB) in north China), where growing season phenology is primarily constrained by low temperatures. The results show that: (i) the incorporation of dynamic growing season (fs) and dynamic effective rooting depth (Ze) conditions into the dBCP model improves results when compared to the original BCP model; (ii) dBCP model's results vary depending on time-step used (i.e., we tested mean-annual to monthly), which reflected the influence of catchment variables, e.g., catchment area, catchment-average air temperature, dryness index and Ze; and (iii) actual evapotranspiration (E) is more sensitive to changes in mean storm depth (α), followed by P, Ze, and Ep. When taking into account observed variability of each of four ecohydrological variables, changes in Ze cause the greatest variability in E, generally followed by variability in P and α, and then Ep. The dBCP results indicate that incorporating dynamic ecohydrological processes into the Budyko framework can improve the estimation of inter-annual variability of the regional water balance. This can help to understand the water requirement and to establish suitable water management strategies to adapt to climate

  13. Proximity to encroaching coconut palm limits native forest water use and persistence on a Pacific atoll

    USGS Publications Warehouse

    Krauss, Ken W.; Duberstein, Jamie A.; Cormier, Nicole; Young, Hillary S.; Hathaway, Stacie A.

    2015-01-01

    Competition for fresh water between native and introduced plants is one important challenge facing native forests as rainfall variability increases. Competition can be especially acute for vegetation on Pacific atolls, which depend upon consistent rainfall to replenish shallow groundwater stores. Patterns of sap flow, water use, and diameter growth of Pisonia grandis trees were investigated on Sand Islet, Palmyra Atoll, Line Islands, during a period of low rainfall. Sap flow in the outer sapwood was reduced by 53% for P. grandis trees growing within coconut palm (Cocos nucifera) stands (n = 9) versus away from coconut palm (n = 9). This suggested that water uptake was being limited by coconut palm. Radial patterns of sap flow into the sapwood of P. grandis also differed between stands with and without coconut palm, such that individual tree water use for P. grandis ranged from 14 to 67 L day−1, averaging 47·8 L day−1 without coconut palm and 23·6 L day−1 with coconut palm. Diameter growth of P. grandis was measured from nine islets. In contrast to sap flow, competition with coconut palm increased diameter growth by 89%, equating to an individual tree basal area increment of 5·4 versus 10·3 mm2 day−1. Greater diameter growth countered by lower rates of water use by P. grandis trees growing in competition with coconut palm suggests that stem swell may be associated with water storage when positioned in the understory of coconut palm, and may facilitate survival when water becomes limiting until too much shading overwhelms P. grandis. 

  14. Using the optimality hypothesis to predict vegetation indices in a water limited environment

    NASA Astrophysics Data System (ADS)

    van der Tol, C.; Meesters, A.; Dolman, H.; Waterloo, M.

    2009-12-01

    In two recent papers, a conceptual model was presented to predict optimum vegetation parameters given climatic constraints (Van der Tol et al., WRR 44 W03421 & W03422, 2008). The vegetation parameters used in these papers, notably photosynthetic capacity and a water use efficiency parameter, are relevant for the cycles of carbon and water. These parameters are not constants, but functions of the available soil moisture and atmospheric conditions. The model is based on the assumption, that photosynthesis and transpiration are regulated in such a way, that net growth is maximised. The model was tested using field measurements of micrometeorological variables, sap flow, 13C-isotope and chemical analysis of leaves, in undisturbed sub-Mediterranean forests. The model reproduced the observed seasonal course of transpiration, both in a dry and an average year, and both on a north and a south facing slope. As a next step, the model has been tested for a larger spatial scale, by using time series of precipitation, humidity and NDVI for selected sites on the Iberian Peninsula, across a gradient of increasing annual precipitation.

  15. Water Quality Trends in the Entiat River Subbasin: Final Annual Report to BPA and NOAA Fisheries, 2008.

    SciTech Connect

    Woodsmith, Richard; Bookter, Andy

    2008-03-11

    The Integrated Status and Effectiveness Monitoring Project (ISEMP) program monitors the status and trend of water quality elements that may affect restoration project effectiveness in the Entiat subbasin. As part of this effort, the PNW Research Station (PNW) measures, analyzes and interprets temporal trends in natural stream water pH, dissolved oxygen, specific conductance and temperature. The Entiat River is currently on the Clean Water Act 303(d) list for pH exceedence, and there is insufficient information to determine the spatial and temporal extent or potential causes of this exceedence. In the late spring 2007, PNW deployed data-logging, multiparameter probes at four locations in the Entiat subbasin to measure water quality parameters, focusing on pH. Data collection was seasonally interrupted by river ice in early December. Daily average pH did not exceed the water quality standard of 8.5 at any of the measurements sites. However, instantaneous values did exceed this standard near the mouth of the Entiat River during late summer-fall period. This suggested that in the lowest portion of the river peaks in pH may be occurring because of photosynthesis caused by high rates of periphyton productivity in response to increased sunlight, temperature, and possible nutrient enrichment. Conversely, dissolved oxygen reached annual low levels during this same late summer-fall period, in part because of increased water temperatures and increased biochemical oxygen demand.

  16. Investigation of detection limits for solutes in water measured by laser raman spectrometry

    USGS Publications Warehouse

    Goldberg, M.C.

    1977-01-01

    The influence of experimental parameters on detection sensitivity was determined for laser Raman analysis of dissolved solutes in water. Individual solutions of nitrate, sulfate, carbonate, bicarbonate, monohydrogen phosphate, dihydrogen phosphate, acetate ion, and acetic acid were measured. An equation is derived which expresses the signal-to-noise ratio in terms of solute concentration, measurement time, spectral slit width, laser power fluctuations, and solvent background intensity. Laser beam intensity fluctuations at the sample and solvent background intensity are the most important limiting factors.

  17. Annual water-level measurements in observation wells, 1951-1955, and atlas of maps showing changes in water levels for various periods from beginning of record through 1954, New Mexico

    USGS Publications Warehouse

    Reeder, Harold O.

    1959-01-01

    This report tabulates the annual measurements of water level in the observation wells in the various irrigated areas, primarily from 1951 through 1955. It summarizes changes in water level by discussion and with an atlas of nearly all the maps of change of water level for the period of record to 1955 for each area in which observations are being made. Included also are hydrographs for the period of record through 1954 of several selected wells in the various areas irrigated from ground-water sources. The annual measurements of water level before 1951, seasonal measurements, and daily records of water levels in wells equipped with recording gages have been published in an annual series of U. S. Geological Survey water-supply papers.

  18. Stocking of Offsite Waters for Hungry Horse Dam Mitigation; Creston National Fish Hatchery, 2001-2002 Annual Report.

    SciTech Connect

    Maskill, Mark

    2003-03-01

    Mitigation Objective 1: Produce Native Westslope Cutthroat Trout at Creston NFH--Task: Acquire eggs and rear up to 100,000 Westslope Cutthroat trout annually for offsite mitigation stocking. Accomplishments: A total of 150,000 westslope cutthroat eggs (M012 strain) were acquired from the State of Montana Washoe Park State Fish Hatchery in July 2001 for this objective. Another 120,000 westslope cutthroat eggs were taken from feral fish at Rogers Lake in May of 2001 by the Creston Hatchery crew. The fish were reared using approved fish culture techniques as defined in the U.S. Department of the Interior Fish Hatchery Management guidelines. Post release survival and angler success is monitored annually by Montana Fish Wildlife and Parks (MFWP) and the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations may vary yearly based on results of biological monitoring. Mitigation Objective 2: Produce Rainbow Trout at Creston NFH--Task: Acquire and rear up to 100,000 Rainbow trout annually for offsite mitigation in closed basin waters. Accomplishments: A total of 50,500 rainbow trout eggs (Arlee strain) were acquired from the State of Montana Arlee State Fish Hatchery in December 2001 for this objective. The fish were reared using approved fish culture techniques as defined in the U.S. Department of the Interior Fish Hatchery Management guidelines. Arlee rainbow trout are being used for this objective because the stocking locations are terminal basin reservoirs and habitat conditions and returns to creel are unsuitable for native cutthroat. Post release survival and angler success is monitored annually by the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations may vary yearly based on results of biological monitoring.

  19. Linking carbon and water limitations to drought-induced mortality of Pinus flexilis seedlings

    USGS Publications Warehouse

    Reinhardt, Keith; Germino, Matthew J.; Kueppers, Lara M.; Domec, Jean-Christophe; Mitton, Jeffry

    2015-01-01

    Survival of tree seedlings at high elevations has been shown to be limited by thermal constraints on carbon balance, but it is unknown if carbon relations also limit seedling survival at lower elevations, where water relations may be more important. We measured and modeled carbon fluxes and water relations in first-year Pinus flexilis seedlings in garden plots just beyond the warm edge of their natural range, and compared these with dry-mass gain and survival across two summers. We hypothesized that mortality in these seedlings would be associated with declines in water relations, more so than with carbon-balance limitations. Rather than gradual declines in survivorship across growing seasons, we observed sharp, large-scale mortality episodes that occurred once volumetric soil-moisture content dropped below 10%. By this point, seedling water potentials had decreased below −5 MPa, seedling hydraulic conductivity had decreased by 90% and seedling hydraulic resistance had increased by >900%. Additionally, non-structural carbohydrates accumulated in aboveground tissues at the end of both summers, suggesting impairments in phloem-transport from needles to roots. This resulted in low carbohydrate concentrations in roots, which likely impaired root growth and water uptake at the time of critically low soil moisture. While photosynthesis and respiration on a leaf area basis remained high until critical hydraulic thresholds were exceeded, modeled seedling gross primary productivity declined steadily throughout the summers. At the time of mortality, modeled productivity was insufficient to support seedling biomass-gain rates, metabolism and secondary costs. Thus the large-scale mortality events that we observed near the end of each summer were most directly linked with acute, episodic declines in plant hydraulic function that were linked with important changes in whole-seedling carbon relations.

  20. Water Budget Managers Report to Northwest Power Planning Council, 1986 Annual Report.

    SciTech Connect

    Karr, Malcolm; DeHart, Michele

    1986-12-01

    In addition to management of the Water Budget, the Water Budget Managers and FPC staff developed and directed the Smolt Monitoring and Water Budget Evaluation Programs of Section 304(d) of the Fish and Wildlife Program. The fishery agencies and tribes also authorized the Water Budget Managers to coordinate agency and tribal system operational requests throughout the year, including spill management for fish passage. This report summarizes Water Budget Manager activities in implementing program measures, including 1986 flow conditions, water budget usage and spill management, and the in-season management portion of the 1986 Smolt Monitoring Program including data management.

  1. Fiscal year 1987 program report (Massachusetts Water Resources Research Center). Annual report

    SciTech Connect

    Godfrey, P.J.

    1988-12-01

    The 1987-88 Massachusetts WRRC program (Federal FY87) focused on areas of high priority for the state and region: acid-deposition impacts, minimization of nitrate ground-water contamination, drinking water pricing, and proposed water diversion from a 'Wild and Scenic' river. The Water Resources Institute Program (WRIP) projects studied central Massachusetts cloud and fog acidity, peat use in rural sewage systems to minimize nitrate ground-water contamination, and determination of true water costs to help plan new sources or infrastructure renovation.

  2. Annual water-resources review, White Sands Missile Range, 1976: a basic-data report

    USGS Publications Warehouse

    Cruz, R.R.

    1977-01-01

    Information is presented on the water resources of the White Sands Missile Range, N. Mex., that was collected during the period December 1975 to December 1976 by personnel of the U.S. Geological Survey, Water Resources Division. Data on ground-water pumpage and resulting water-level fluctuation, chemical quality and precipitation, and miscellaneous items of interest are summarized. Water-level observations were made in 63 borehole, supply, test, and observation wells on the Range. Water samples were collected and analyzed for chemical quality from 8 test wells. (Woodard-USGS)

  3. Limitations of Snow-Water Equivalent and Precipitation Data in Seasonal Flow Forecasting in the Upper Klamath River Basin of Oregon and California

    NASA Astrophysics Data System (ADS)

    Risley, J. C.; Roehl, E. A.

    2005-12-01

    Water managers in the upper Klamath Basin, located in south-central Oregon and northeastern California, rely on accurate forecasts of spring and summer streamflow to optimally allocate increasingly limited water supplies for various demands that include irrigation for agriculture, habitat for endangered fishes, and hydropower production. Federal agencies make forecasts on the 1st of each month, from January through May, of the total volume of water expected to pass a stream gage or flow into a reservoir during an entire summer irrigation season. Often the forecasts are based on output from flow forecast models that use real-time snow-water equivalent (SWE) and precipitation data as input. Because the January and February forecasts are significantly less accurate than those made in the spring, we were interested in quantifying the limitations of real-time SWE and precipitation data in forecasting future flows. Using over 20 years of daily SWE, precipitation, and flow time-series from five sites in the upper Klamath Basin, we first decomposed the flow records into annual periodic, long-term climatic, and chaotic traces. Being the component of the original flow records with their seasonality and long-term trends removed, the chaotic traces were then lag correlated with SWE and precipitation records. After a 120 day lag (approximately 4 months), all of the correlation coefficients between the chaotic flow traces and the SWE and precipitation records were less than 0.4. From this, we could infer that SWE and precipitation data older than 120 days provide forecast models only with information regarding the annual seasonal and long-term climate patterns and do not provide information that is unique and specific for the upcoming irrigation season. These results also support the need to find new climate variables, such as mid-oceanic indicators, to improve forecast model accuracy rather than using just real-time SWE and precipitation conditions.

  4. Effects of irrigation water supply variations on limited resource farming in Conejos County, Colorado

    NASA Astrophysics Data System (ADS)

    Eckert, Jerry B.; Wang, Erda

    1993-02-01

    Farms in NE Conejos County, Colorado, are characterized by limited resources, uncertain surface flow irrigation systems, and mixed crop-livestock enterprise combinations which are dependent on public grazing resources. To model decision making on these farms, a linear program is developed stressing enterprise choices under conditions of multiple resource constraints. Differential access to grazing resources and irrigation water is emphasized in this research. Regarding the water resource, the model reflects farms situated alternatively on high-, medium-, and low-priority irrigation ditches within the Alamosa-La Jara river system, each with and without supplemental pumping. Differences are found in optimum enterprise mixes, net returns, choice of cropping technology, level of marketings, and other characteristics in response to variations in the availability of irrigation water. Implications are presented for alternative improvement strategies.

  5. Using containment analysis to improve component cooling water heat exchanger limits

    SciTech Connect

    Da Silva, H.C.; Tajbakhsh, A.

    1995-12-31

    The Comanche Peak Steam Electric Station design requires that exit temperatures from the Component Cooling Water Heat Exchanger remain below 330.37 K during the Emergency Core Cooling System recirculation stage, following a hypothetical Loss of Coolant Accident (LOCA). Due to measurements indicating a higher than expected combination of: (a) high fouling factor in the Component Cooling Water Heat Exchanger with (b) high ultimate heat sink temperatures, that might lead to temperatures in excess of the 330.37 K limit, if a LOCA were to occur, TUElectric adjusted key flow rates in the Component Cooling Water network. This solution could only be implemented with improvements to the containment analysis methodology of record. The new method builds upon the CONTEMPT-LT/028 code by: (a) coupling the long term post-LOCA thermohydraulics with a more detailed analytical model for the complex Component Cooling Water Heat Exchanger network and (b) changing the way mass and energy releases are calculated after core reflood and steam generator energy is dumped to the containment. In addition, a simple code to calculate normal cooldowns was developed to confirm RHR design bases were met with the improved limits.

  6. Plant responses, climate pivot points, and trade-offs in water-limited ecosystems

    USGS Publications Warehouse

    Munson, Seth M.

    2013-01-01

    Plant species in dryland ecosystems are limited by water availability and may be vulnerable to increases in aridity. Methods are needed to monitor and assess the rate of change in plant abundance and composition in relation to climate, understand the potential for degradation in dryland ecosystems, and forecast future changes in plant species assemblages. I employ nearly a century of vegetation monitoring data from three North American deserts to demonstrate an approach to determine plant species responses to climate and critical points over a range of climatic conditions at which plant species shift from increases to decreases in abundance (climate pivot points). I assess these metrics from a site to regional scale and highlight how these indicators of plant performance can be modified by the physical and biotic environment. For example, shrubs were more responsive to drought and high temperatures on shallow soils with limited capacity to store water and fine-textured soils with slow percolation rates, whereas perennial grasses were more responsive to precipitation in sparse shrublands than in relatively dense grasslands and shrublands, where competition for water is likely more intense. The responses and associated climate pivot points of plant species aligned with their lifespan and structural characteristics, and the relationship between responses and climate pivot points provides evidence of the trade-off between the capacity of a plant species to increase in abundance when water is available and its drought resistance.

  7. Water Budget Managers Report to Northwest Power Planning Council, 1985 Annual Report.

    SciTech Connect

    Karr, Malcolm H., Maher, Mark

    1985-11-01

    1985 was the third year of operation of the Water Budget Center under the guidance and supervision of the fishery agencies and tribal Water Budget Managers, and the second year of formal water budget implementation. The Water Budget Managers also directed the Smolt Monitoring and Water Budget Evaluation Programs of Section 304(d) of the Fish and wildlife Program. The Water Budget Managers work to implement policies and priorities of the state and federal fishery agencies and Indian tribes in carrying out applicable measures of the Fish and Wildlife Program. This report summarizes Water Budget Manager activities in implementing program measures, including 1985 flow conditions, water budget usage and spill management and problems encountered, and the 1985 Smolt Monitoring Program and preliminary results. Recommendations are included.

  8. Annual summary of ground-water conditions in Arizona, spring 1979 to spring 1980

    USGS Publications Warehouse

    ,

    1981-01-01

    Withdrawal of ground water, about 4.0 million acre-feet in Arizona in 1979, is about 200,000 acre-feet less than the amount withdrawn in 1978. The withdrawals in 1978 and 1979 are the smallest since the mid-1950 's except in 1966. Nearly all the decrease was in the amount of ground water used for irrigation in the Basin and Range lowlands province. The large amount of water in storage in the surface-water reservoirs, release of water from the reservoirs, floods, and conservation practices contributed to the decrease in ground-water use and caused water-level rises in the Salt River Valley, Gila Bend basin, and Gila River drainage from Painted Rock Dam to Texas Hill. Two small-scale maps show ground-water pumpage by areas and the status of the ground-water inventory in the State. The main map, which is at a scale of 1:500,000, shows potential well production, depth to water in selected wells in spring 1980, and change in water level in selected wells from 1975 to 1980. A brief text summarizes the current ground-water conditions in the State. (USGS)

  9. Estimating root zone soil water content using limited soils information and surface soil moisture data assimilation

    NASA Astrophysics Data System (ADS)

    Heathman, Gary Claude

    2001-10-01

    The various hydrologic processes of infiltration, redistribution, drainage, evaporation, and water uptake by plants are strongly interdependent, as they occur sequentially or simultaneously. An important state variable that strongly influences the magnitude to which these rate processes occur is the amount of water present within the root zone, and in particular, the top few centimeters near the soil surface. Traditionally, measurements of soil moisture have been limited to point measurements made in the field. In general, averages of point measurements are used to characterize the soil moisture of an area, but these averages seldom yield information that is adequate to characterize large scale hydrologic processes. Recent advancements in remote sensing now make it possible to obtain areal estimates of surface soil moisture. The use of remotely sensed data to estimate surface soil moisture, combined with soil water and hydrologic modeling, provides a unique opportunity to advance our understanding of hydrologic processes at a much larger scale. Standard techniques for measuring soil moisture have been well documented, with commercial instrumentation being widely available. Various computer models have been developed to estimate soil moisture in the root and vadose zone, although their application over large scales is limited due to varying spatial and temporal field conditions. It is the combination of ground-based data (in-situ measurements), near-surface soil moisture data, and modeling that form the basis for this research. The interactive use of field research, remote sensing ground truth data, and integrated systems modeling is used to describe surface and profile soil moisture conditions at several locations within a large watershed. Successful application of this approach should improve our capabilities for estimating soil hydraulic properties and to better estimate water and chemical transport in the root zone, thus enhancing water use efficiency and plant

  10. 2014 annual summary of the lower Gunnison River Basin Selenium Management Program water-quality monitoring, Colorado

    USGS Publications Warehouse

    Henneberg, Mark F.

    2016-08-10

    Dissolved-selenium loading analyses of data collected at 18 water-quality sites in the lower Gunnison River Basin in Colorado were completed through water year (WY) 2014. A WY is defined as October 1–September 30. Selenium is a trace element that bioaccumulates in aquatic food chains and can cause reproductive failure, deformities, and other harmful effects. This report presents information on the dissolved-selenium loads at 18 sites in the lower Gunnison River Basin for WYs 2011–2014. Annual dissolved-selenium loads were calculated at 5 sites with continuous U.S. Geological Survey (USGS) streamflow gages, whereas instantaneous dissolved-selenium loads were calculated for the remaining 13 sites using water-quality samples that had been collected periodically during WYs 2011–2014. Annual dissolved-selenium loads for WY 2014 ranged from 336 pounds (lb) at Uncompahgre River at Colona to 13,300 lb at Gunnison River near Grand Junction (Whitewater). Most sites in the basin had a median instantaneous dissolved-selenium load of less than 20.0 lb per day. In general, dissolved-selenium loads at Gunnison River main-stem sites showed an increase from upstream to downstream.The State of Colorado water-quality standard for dissolved selenium of 4.6 micrograms per liter (µg/L) was compared to the 85th percentiles for dissolved selenium at selected water-quality sites. Annual 85th percentiles for dissolved selenium were calculated for the five core USGS sites having streamflow gages using estimated dissolved-selenium concentrations from linear regression models. These annual 85th percentiles in WY 2014 ranged from 0.97 µg/L at Uncompahgre River at Colona to 16.7 µg/L at Uncompahgre River at Delta. Uncompahgre River at Delta and Whitewater were the only core sites where water samples exceeded the State of Colorado water-quality standard for dissolved selenium of 4.6 µg/L.Instantaneous 85th percentiles for dissolved selenium were calculated for sites with sufficient data

  11. Thermochemical water-splitting cycle, bench-scale investigations and process engineering. Annual report, October 1, 1978-September 30, 1979

    SciTech Connect

    Caprioglio, G.; McCorkle, K.H.; Besenbruch, G.E.; Rode, J.S.

    1980-03-01

    A program to investigate thermochemical water splitting has been under way at General Atomic Company (GA) since October 1972. This document is an annual progress report of Department of Energy (DOE) sponsored process development work on the GA sulfur-iodine thermochemical water splitting cycle. The work consisted of laboratory bench-scale investigations, demonstration of the process in a closed-loop cycle demonstrator, and process engineering design studies. A bench-scale system, consisting of three subunits, has been designed to study the cycle under continuous flow conditions. The designs of subunit I, which models the main solution reaction and product separation, and subunit II, which models the concentration and decomposition of sulfuric acid, were presented in an earlier annual report. The design of subunit III, which models the purification and decomposition of hydrogen iodide, is given in this report. Progress on the installation and operation of subunits I and II is described. A closed-loop cycle demonstrator was installed and operated based on a DOE request. Operation of the GA sulfur-iodine cycle was demonstrated in this system under recycle conditions. The process engineering addresses the flowsheet design of a large-scale production process consisting of four chemical sections (I through IV) and one helium heat supply section (V). The completed designs for sections I through V are presented. The thermal efficiency of the process calculated from the present flowsheet is 47%.

  12. Assessment of wildland fire impacts on watershed annual water yield: Analytical framework and case studies in the United States

    SciTech Connect

    Hallema, Dennis W.; Sun, Ge; Caldwell, Peter V.; Norman, Steven P.; Cohen, Erika C.; Liu, Yongqiang; Ward, Eric J.; McNulty, Steven G.

    2016-11-29

    More than 50% of water supplies in the conterminous United States originate on forestland or rangeland and are potentially under increasing stress as a result of larger and more severe wildfires. Little is known, however, about the long-term impacts of fire on annual water yield and the role of climate variability within this context. We here propose a framework for evaluating wildland fire impacts on streamflow that combines double-mass analysis with new methods (change point analysis, climate elasticity modeling, and process-based modeling) to distinguish between multiyear fire and climate impacts. The framework captures a wide range of fire types, watersheds characteristics, and climate conditions using streamflow data, as opposed to other approaches requiring paired watersheds. The process is illustrated with three case studies. A watershed in Arizona experienced a +266% increase in annual water yield in the 5 years after a wildfire, where +219% was attributed to wildfire and +24% to precipitation trends. In contrast, a California watershed had a lower (–64%) post-fire net water yield, comprised of enhanced flow (+38%) attributed to wildfire offset (–102%) by lower precipitation in the post-fire period. Changes in streamflow within a watershed in South Carolina had no apparent link to periods of prescribed burning but matched a very wet winter and reports of storm damage. As a result, the presented framework is unique in its ability to detect and quantify fire or other disturbances, even if the date or nature of the disturbance event is uncertain, and regardless of precipitation trends.

  13. Assessment of wildland fire impacts on watershed annual water yield: Analytical framework and case studies in the United States

    DOE PAGES

    Hallema, Dennis W.; Sun, Ge; Caldwell, Peter V.; ...

    2016-11-29

    More than 50% of water supplies in the conterminous United States originate on forestland or rangeland and are potentially under increasing stress as a result of larger and more severe wildfires. Little is known, however, about the long-term impacts of fire on annual water yield and the role of climate variability within this context. We here propose a framework for evaluating wildland fire impacts on streamflow that combines double-mass analysis with new methods (change point analysis, climate elasticity modeling, and process-based modeling) to distinguish between multiyear fire and climate impacts. The framework captures a wide range of fire types, watershedsmore » characteristics, and climate conditions using streamflow data, as opposed to other approaches requiring paired watersheds. The process is illustrated with three case studies. A watershed in Arizona experienced a +266% increase in annual water yield in the 5 years after a wildfire, where +219% was attributed to wildfire and +24% to precipitation trends. In contrast, a California watershed had a lower (–64%) post-fire net water yield, comprised of enhanced flow (+38%) attributed to wildfire offset (–102%) by lower precipitation in the post-fire period. Changes in streamflow within a watershed in South Carolina had no apparent link to periods of prescribed burning but matched a very wet winter and reports of storm damage. As a result, the presented framework is unique in its ability to detect and quantify fire or other disturbances, even if the date or nature of the disturbance event is uncertain, and regardless of precipitation trends.« less

  14. Annual water-resources review White Sands Missile Range, New Mexico

    USGS Publications Warehouse

    Cruz, R.R.

    1980-01-01

    Ground-water data were collected in 1979 at White Sands Missile Range in south-central New Mexico. Total ground-water pumpage from the Post Headquarters well field, which produces more than 98% of the water used at White Sands Missile Range, was 1.4 million gallons more in 1979 than in 1978. The most significant seasonal water-level declines observed in 1979 were in supply well 22 (36.35 feet) and test well T-7 (15.98 feet). The chemical quality of water samples collected in 1979 was similar to that collected at comparable depths and periods in 1978. (USGS)

  15. Annual water-resources review, White Sands Missile Range, New Mexico, 1978

    USGS Publications Warehouse

    Cruz, R.R.

    1979-01-01

    Ground-water data were collected in 1978 at White Sands Missile Range in south-central New Mexico. Total ground-water pumpage in 1978 was 692,045,700 gallons or 7,248,300 less than in 1977. Wells at the Post Headquarters produced 98 percent of the total volume. Water levels in test wells around the Post Headquarters well field show seasonal declines ranging from 14.78 feet to 0.71 feet. The water samples collected from the supply wells show that the chemical quality of the water is slightly better during the period of greatest declines. (Woodard-USGS)

  16. Some simulation estimates of mean annual increment of douglas-fir: Results, limitations, and implications for management. Forest Service research paper

    SciTech Connect

    Curtis, R.O.

    1994-04-01

    Patterns of development of mean annual increment in relation to age predicted by the widely used DFSM, SPS, TASS, and ORGANON simulators were examined. Although predictions differ considerably among simulators for portions of the range of sites, ages, and treatments, comparisons indicated that (1) culmination is relatively late, (2) the curve is relatively flat in the vicinity of culmination, and (3) systematic thinning tends to delay culmination. Harvest ages of 40 to 50 years reduce volume production relative to potential by amounts ranging from moderate to large according to site, treatment regime, and simulator. Within unknown upper limits, moderate extension of rotations to minimize conflicts among timber production and environmental, aesthetic, and wildlife values would not materially reduce long-term volume production and might increase value production.

  17. Is there a common water-activity limit for the three domains of life?

    PubMed Central

    Stevenson, Andrew; Cray, Jonathan A; Williams, Jim P; Santos, Ricardo; Sahay, Richa; Neuenkirchen, Nils; McClure, Colin D; Grant, Irene R; Houghton, Jonathan DR; Quinn, John P; Timson, David J; Patil, Satish V; Singhal, Rekha S; Antón, Josefa; Dijksterhuis, Jan; Hocking, Ailsa D; Lievens, Bart; Rangel, Drauzio E N; Voytek, Mary A; Gunde-Cimerman, Nina; Oren, Aharon; Timmis, Kenneth N; McGenity, Terry J; Hallsworth, John E

    2015-01-01

    Archaea and Bacteria constitute a majority of life systems on Earth but have long been considered inferior to Eukarya in terms of solute tolerance. Whereas the most halophilic prokaryotes are known for an ability to multiply at saturated NaCl (water activity (aw) 0.755) some xerophilic fungi can germinate, usually at high-sugar concentrations, at values as low as 0.650–0.605 aw. Here, we present evidence that halophilic prokayotes can grow down to water activities of <0.755 for Halanaerobium lacusrosei (0.748), Halobacterium strain 004.1 (0.728), Halobacterium sp. NRC-1 and Halococcus morrhuae (0.717), Haloquadratum walsbyi (0.709), Halococcus salifodinae (0.693), Halobacterium noricense (0.687), Natrinema pallidum (0.681) and haloarchaeal strains GN-2 and GN-5 (0.635 aw). Furthermore, extrapolation of growth curves (prone to giving conservative estimates) indicated theoretical minima down to 0.611 aw for extreme, obligately halophilic Archaea and Bacteria. These were compared with minima for the most solute-tolerant Bacteria in high-sugar (or other non-saline) media (Mycobacterium spp., Tetragenococcus halophilus, Saccharibacter floricola, Staphylococcus aureus and so on) and eukaryotic microbes in saline (Wallemia spp., Basipetospora halophila, Dunaliella spp. and so on) and high-sugar substrates (for example, Xeromyces bisporus, Zygosaccharomyces rouxii, Aspergillus and Eurotium spp.). We also manipulated the balance of chaotropic and kosmotropic stressors for the extreme, xerophilic fungi Aspergillus penicilloides and X. bisporus and, via this approach, their established water-activity limits for mycelial growth (∼0.65) were reduced to 0.640. Furthermore, extrapolations indicated theoretical limits of 0.632 and 0.636 aw for A. penicilloides and X. bisporus, respectively. Collectively, these findings suggest that there is a common water-activity limit that is determined by physicochemical constraints for the three domains of life. PMID:25500507

  18. Is there a common water-activity limit for the three domains of life?

    PubMed

    Stevenson, Andrew; Cray, Jonathan A; Williams, Jim P; Santos, Ricardo; Sahay, Richa; Neuenkirchen, Nils; McClure, Colin D; Grant, Irene R; Houghton, Jonathan Dr; Quinn, John P; Timson, David J; Patil, Satish V; Singhal, Rekha S; Antón, Josefa; Dijksterhuis, Jan; Hocking, Ailsa D; Lievens, Bart; Rangel, Drauzio E N; Voytek, Mary A; Gunde-Cimerman, Nina; Oren, Aharon; Timmis, Kenneth N; McGenity, Terry J; Hallsworth, John E

    2015-06-01

    Archaea and Bacteria constitute a majority of life systems on Earth but have long been considered inferior to Eukarya in terms of solute tolerance. Whereas the most halophilic prokaryotes are known for an ability to multiply at saturated NaCl (water activity (a(w)) 0.755) some xerophilic fungi can germinate, usually at high-sugar concentrations, at values as low as 0.650-0.605 a(w). Here, we present evidence that halophilic prokayotes can grow down to water activities of <0.755 for Halanaerobium lacusrosei (0.748), Halobacterium strain 004.1 (0.728), Halobacterium sp. NRC-1 and Halococcus morrhuae (0.717), Haloquadratum walsbyi (0.709), Halococcus salifodinae (0.693), Halobacterium noricense (0.687), Natrinema pallidum (0.681) and haloarchaeal strains GN-2 and GN-5 (0.635 a(w)). Furthermore, extrapolation of growth curves (prone to giving conservative estimates) indicated theoretical minima down to 0.611 aw for extreme, obligately halophilic Archaea and Bacteria. These were compared with minima for the most solute-tolerant Bacteria in high-sugar (or other non-saline) media (Mycobacterium spp., Tetragenococcus halophilus, Saccharibacter floricola, Staphylococcus aureus and so on) and eukaryotic microbes in saline (Wallemia spp., Basipetospora halophila, Dunaliella spp. and so on) and high-sugar substrates (for example, Xeromyces bisporus, Zygosaccharomyces rouxii, Aspergillus and Eurotium spp.). We also manipulated the balance of chaotropic and kosmotropic stressors for the extreme, xerophilic fungi Aspergillus penicilloides and X. bisporus and, via this approach, their established water-activity limits for mycelial growth (∼0.65) were reduced to 0.640. Furthermore, extrapolations indicated theoretical limits of 0.632 and 0.636 a(w) for A. penicilloides and X. bisporus, respectively. Collectively, these findings suggest that there is a common water-activity limit that is determined by physicochemical constraints for the three domains of life.

  19. Dynamics of a deep-water seagrass population on the Great Barrier Reef: annual occurrence and response to a major dredging program

    PubMed Central

    York, Paul H.; Carter, Alex B.; Chartrand, Kathryn; Sankey, Tonia; Wells, Linda; Rasheed, Michael A.

    2015-01-01

    Global seagrass research efforts have focused on shallow coastal and estuarine seagrass populations where alarming declines have been recorded. Comparatively little is known about the dynamics of deep-water seagrasses despite evidence that they form extensive meadows in some parts of the world. Deep-water seagrasses are subject to similar anthropogenic threats as shallow meadows, particularly along the Great Barrier Reef lagoon where they occur close to major population centres. We examine the dynamics of a deep-water seagrass population in the GBR over an 8 year period during which time a major capital dredging project occurred. Seasonal and inter-annual changes in seagrasses were assessed as well as the impact of dredging. The seagrass population was found to occur annually, generally present between July and December each year. Extensive and persistent turbid plumes from a large dredging program over an 8 month period resulted in a failure of the seagrasses to establish in 2006, however recruitment occurred the following year and the regular annual cycle was re-established. Results show that despite considerable inter annual variability, deep-water seagrasses had a regular annual pattern of occurrence, low resistance to reduced water quality but a capacity for rapid recolonisation on the cessation of impacts. PMID:26279474

  20. Methods for estimating annual exceedance probability discharges for streams in Arkansas, based on data through water year 2013

    USGS Publications Warehouse

    Wagner, Daniel M.; Krieger, Joshua D.; Veilleux, Andrea G.

    2016-08-04

    In 2013, the U.S. Geological Survey initiated a study to update regional skew, annual exceedance probability discharges, and regional regression equations used to estimate annual exceedance probability discharges for ungaged locations on streams in the study area with the use of recent geospatial data, new analytical methods, and available annual peak-discharge data through the 2013 water year. An analysis of regional skew using Bayesian weighted least-squares/Bayesian generalized-least squares regression was performed for Arkansas, Louisiana, and parts of Missouri and Oklahoma. The newly developed constant regional skew of -0.17 was used in the computation of annual exceedance probability discharges for 281 streamgages used in the regional regression analysis. Based on analysis of covariance, four flood regions were identified for use in the generation of regional regression models. Thirty-nine basin characteristics were considered as potential explanatory variables, and ordinary least-squares regression techniques were used to determine the optimum combinations of basin characteristics for each of the four regions. Basin characteristics in candidate models were evaluated based on multicollinearity with other basin characteristics (variance inflation factor < 2.5) and statistical significance at the 95-percent confidence level (p ≤ 0.05). Generalized least-squares regression was used to develop the final regression models for each flood region. Average standard errors of prediction of the generalized least-squares models ranged from 32.76 to 59.53 percent, with the largest range in flood region D. Pseudo coefficients of determination of the generalized least-squares models ranged from 90.29 to 97.28 percent, with the largest range also in flood region D. The regional regression equations apply only to locations on streams in Arkansas where annual peak discharges are not substantially affected by regulation, diversion, channelization, backwater, or urbanization

  1. Water limitations to carbon exchange in old-growth and young ponderosa pine stands.

    PubMed

    Irvine, J; Law, B E; Anthoni, P M; Meinzer, F C

    2002-02-01

    We investigated the impact of seasonal soil water deficit on the processes driving net ecosystem exchange of carbon (NEE) in old-growth and recently regenerating ponderosa pine (Pinus ponderosa Doug. ex Laws.) stands in Oregon. We measured seasonal patterns of transpiration, canopy conductance and NEE, as well as soil water, soil temperature and soil respiration. The old-growth stand (O) included two primary age classes (50 and 250 years), had a leaf area index (LAI) of 2.1 and had never been logged. The recently regenerating stand (Y) consisted predominantly of 14-year-old ponderosa pine with an LAI of 1.0. Both stands experienced similar meteorological conditions with moderately cold wet winters and hot dry summers. By August, soil volumetric water content within the upper 30 cm had declined to a seasonal minimum of 0.07 at both sites. Between April and June, both stands showed similar rates of transpiration peaking at 0.96 mm day(-1); thereafter, trees at the Y site showed increasing drought stress with canopy stomatal resistance increasing 6-fold by mid-August relative to values for trees at the O site. Over the same period, predawn water potential (psi(pd)) of trees at the Y site declined from -0.54 to -1.24 MPa, whereas psi(pd) of trees at the O site remained greater than -0.8 MPa throughout the season. Soil respiration at the O site showed a strong seasonal correlation with soil temperature with no discernible constraints imposed by declining soil water. In contrast, soil respiration at the Y site peaked before seasonal maximal soil temperatures and declined thereafter with declining soil water. No pronounced seasonal pattern in daytime NEE was observed at either site between April and September. At the Y site this behavior was driven by concurrent soil water limitations on soil respiration and assimilation, whereas there was no evidence of seasonal soil water limitations on either process at the O site.

  2. Impacts of Water Level Fluctuations on Kokanee Reproduction in Flathead Lake, 1984 Annual Report.

    SciTech Connect

    Decker-Hess, Janet; Clancey, Patrick

    1984-03-01

    This study was initiated in the fall of 1981 to delineate the extent of successful shoreline spawning of kokanee salmon in Flathead Lake and determine the impacts of the historic and present operations of Kerr and Hungry Horse dams. An investigation of the quantity and quality of groundwater and other factors affecting kokanee reproductive success in Flathead Lake began in the spring of 1982. A total of 719 redds were counted in 17 shoreline areas of Flathead Lake in1983 compared to 592 in 1981 and 1,029 in 1982. Shoreline spawning contributed three percent to the total kokanee spawning in the Flathead drainage in 1983. Fifty-nine percent of the redds were located above 2883 ft, the operational minimum pool. The majority of those redds were constructed between 2885 and 2889 ft. In areas above minimum pool, intergravel dissolved oxygen concentrations were adequate for embryo survival and exhibited a decrease with depth. Limited data indicated apparent velocity may be the key in determining redd distribution. Seventy-five percent of the redds located below minimum pool were constructed in a zone between 2869 and 2883 ft. In individual areas, apparent velocity measurements and intergravel dissolved oxygen concentrations were related to redd density. The variation in intergravel dissolved oxygen concentrations in the Yellow Bay spawning area was partially explained by lake stage fluctuation. As lake stage declined, groundwater apparent velocity increased which increased intergravel dissolved oxygen concentrations. Mean survival to the eyed stage in the three areas below minimum pool was 43 percent. Prior to exposure by lake drawdown, mean survival to the eyed stage in spawning areas above minimum pool was 87 percent. This indicated habitat most conducive to successful embryo survival was in gravels above 2883 ft. prior to significant exposure. Survival in redds exposed to either extended periods of drawdown or to temperatures less than -10% was significantly reduced to

  3. Annual water resources review, White Sands Missile Range, New Mexico, 1980

    USGS Publications Warehouse

    Cruz, R.R.

    1981-01-01

    Ground-water data were collected in 1980 at White Sands Missile Range in south-central New Mexico. The total water pumped at White Sands Missile Range in 1980 was 725,053,000 gallons, which was 32.5 million gallons more than in 1979. The Post Headquarters well field, which produces more than 98 percent of the water used at White Sands Missile Range, pumped 712,909,000 gallons, which was 31.1 million gallons more in 1980 than in 1979. Data were collected for specific Range areas north of the Post Headquarters area that might have potential for future water-supply development. (USGS)

  4. Annual water-resources review, White Sands Missile Range, New Mexico

    USGS Publications Warehouse

    Cruz, R.R.

    1983-01-01

    Ground-water data were collected in 1982 at White Sands Missile Range in south-central New Mexico. Depth-to-water measurements in the Post Headquarters supply wells continued to show seasonal declines. Test wells east of the Headquarters well field continue to show long-term declines as well as seasonal fluctuations. The total amount of water pumped from White Sands Missile Range supply wells was 66,226,600 gallons more in 1982 than in 1981. The difference in the specific-conductance values of the water samples collected from the Post Headquarters supply wells in the winter and summer increased in 1982. (USGS)

  5. Annual down-glacier drainage of lakes and water-filled crevasses at Helheim Glacier, southeast Greenland

    NASA Astrophysics Data System (ADS)

    Everett, A.; Murray, T.; Selmes, N.; Rutt, I. C.; Luckman, A.; James, T. D.; Clason, C.; O'Leary, M.; Karunarathna, H.; Moloney, V.; Reeve, D. E.

    2016-10-01

    Supraglacial lake drainage events are common on the Greenland ice sheet. Observations on the west coast typically show an up-glacier progression of drainage as the annual melt extent spreads inland. We use a suite of remote sensing and modeling techniques in order to study a series of lakes and water-filled crevasses within 20 km of the terminus of Helheim Glacier, southeast Greenland. Automatic classification of surface water areas shows a down-glacier progression of drainage, which occurs in the majority of years between 2007 and 2014. We demonstrate that a linear elastic fracture mechanics model can reliably predict the drainage of the uppermost supraglacial lake in the system but cannot explain the pattern of filling and draining observed in areas of surface water downstream. We propose that the water levels in crevasses downstream of the supraglacial lake can be explained by a transient high-pressure wave passing through the subglacial system following the lake drainage. We support this hypothesis with analysis of the subglacial hydrological conditions, which can explain both the position and interannual variation in filling order of these crevasses. Similar behavior has been observed in association with jökulhaups, surging glaciers, and Antarctic subglacial lakes but has not previously been observed on major outlets of the Greenland ice sheet. Our results suggest that the behavior of near-terminus surface water may differ considerably from that of inland supraglacial lakes, with the potential for basal water pressures to influence the presence of surface water in crevasses close to the terminus of tidewater glaciers.

  6. 33 CFR 165.1332 - Safety Zones; annual firework displays within the Captain of the Port, Puget Sound Area of...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Safety Zones; annual firework... Limited Access Areas Thirteenth Coast Guard District § 165.1332 Safety Zones; annual firework displays... from the following launch sites: Captain of the Port Puget Sound AOR Annual Firework Displays...

  7. Traits and selection strategies to improve root systems and water uptake in water-limited wheat crops.

    PubMed

    Wasson, A P; Richards, R A; Chatrath, R; Misra, S C; Prasad, S V Sai; Rebetzke, G J; Kirkegaard, J A; Christopher, J; Watt, M

    2012-05-01

    Wheat yields globally will depend increasingly on good management to conserve rainfall and new varieties that use water efficiently for grain production. Here we propose an approach for developing new varieties to make better use of deep stored water. We focus on water-limited wheat production in the summer-dominant rainfall regions of India and Australia, but the approach is generally applicable to other environments and root-based constraints. Use of stored deep water is valuable because it is more predictable than variable in-season rainfall and can be measured prior to sowing. Further, this moisture is converted into grain with twice the efficiently of in-season rainfall since it is taken up later in crop growth during the grain-filling period when the roots reach deeper layers. We propose that wheat varieties with a deeper root system, a redistribution of branch root density from the surface to depth, and with greater radial hydraulic conductivity at depth would have higher yields in rainfed systems where crops rely on deep water for grain fill. Developing selection systems for mature root system traits is challenging as there are limited high-throughput phenotyping methods for roots in the field, and there is a risk that traits selected in the lab on young plants will not translate into mature root system traits in the field. We give an example of a breeding programme that combines laboratory and field phenotyping with proof of concept evaluation of the trait at the beginning of the selection programme. This would greatly enhance confidence in a high-throughput laboratory or field screen, and avoid investment in screens without yield value. This approach requires careful selection of field sites and years that allow expression of deep roots and increased yield. It also requires careful selection and crossing of germplasm to allow comparison of root expression among genotypes that are similar for other traits, especially flowering time and disease and toxicity

  8. Annual Research Review: Discovery science strategies in studies of the pathophysiology of child and adolescent psychiatric disorders: promises and limitations

    PubMed Central

    Zhao, Yihong; Castellanos, F. Xavier

    2015-01-01

    Background and Scope Psychiatric science remains descriptive, with a categorical nosology intended to enhance inter-observer reliability. Increased awareness of the mismatch between categorical classifications and the complexity of biological systems drives the search for novel frameworks including discovery science in Big Data. In this review, we provide an overview of incipient approaches, primarily focused on classically categorical diagnoses such as schizophrenia (SZ), autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), but also reference convincing, if focal, advances in cancer biology, to describe the challenges of Big Data and discovery science, and outline approaches being formulated to overcome existing obstacles. Findings A paradigm shift from categorical diagnoses to a domain/structure-based nosology and from linear causal chains to complex causal network models of brain-behavior relationship is ongoing. This (r)evolution involves appreciating the complexity, dimensionality and heterogeneity of neuropsychiatric data collected from multiple sources (“broad” data) along with data obtained at multiple levels of analysis, ranging from genes to molecules, cells, circuits and behaviors (“deep” data). Both of these types of Big Data landscapes require the use and development of robust and powerful informatics and statistical approaches. Thus, we describe Big Data analysis pipelines and the promise and potential limitations in using Big Data approaches to study psychiatric disorders. Conclusion We highlight key resources available for psychopathological studies and call for the application and development of Big Data approaches to dissect the causes and mechanisms of neuropsychiatric disorders and identify corresponding biomarkers for early diagnosis. PMID:26732133

  9. Sensitivity of reservoir storage and outflow to climate change in a water-limited river basin

    NASA Astrophysics Data System (ADS)

    Zhao, G.; Gao, H.; Naz, B. S.; Kao, S. C.; Voisin, N.

    2015-12-01

    During the past several decades, numerous reservoirs have been built across the world for a variety of purposes such as flood control, irrigation, municipal water supplies, and hydropower. Consequently, streamflow timing and magnitude are altered significantly by reservoir operations. In addition, the hydrological cycle can be modified substantially by a changing climate. Therefore, a distributed hydrological model which has an embedded reservoir component is essential for representing these effects in future water management planning strategies. In this study, a multi-purpose reservoir module was integrated into the Distributed Hydrology Soil Vegetation Model (DHSVM). The DHSVM model was selected because of its high spatial and temporal resolution and because of its explicit representation of the physical processes. Prescribed operating rules, which are designed to reduce flood risk and enhance water supply reliability, were adopted in this module. The integrated model was tested over a water-limited basin (i.e. the central Brazos River Basin, Texas). Both the calibration and validation results suggest that the model performed robustly at daily, weekly, and monthly levels. Subsequently, the effect of climate sensitivity on reservoir storage and outflow was assessed by perturbing precipitation within a range from -30% to 30% and temperature from -2 °C to 2 °C. Results suggest that both variables are more sensitive to precipitation than temperature. However, there are more uncertainties associated with future precipitation than temperature. It was also found that the sensitivities vary significantly by season. Enabled with the new reservoir component, the DHSVM model provides a platform for projecting future water availability estimations under flow regulation, climate change, and land cover/land use changes. We expect this integrated model to be beneficial for sustainable water resources management.

  10. Ground Water Technical Support Center (GWTSC) Annual Report Fiscal Year 2014 (FY14)

    EPA Science Inventory

    The Ground Water Technical Support Center (GWTSC) is part of the Ground Water and Ecosystems Restoration Division (GWERD), which is based in the Robert S. Kerr Environmental Research Center in Ada, Oklahoma. The GWERD is a research division of U.S. EPA's National Risk Management...

  11. Ground Water Technical Support Center (GWTSC) Annual Report FY 2012: October 2011 – September 2012

    EPA Science Inventory

    The Ground Water Technical Support Center (GWTSC) is part of the Ground Water and Ecosystems Restoration Division (GWERD), which is based in the Robert S. Kerr Environmental Research Center in Ada, Oklahoma. The GWERD is a research division of U.S. EPA's National Risk Management...

  12. Proceedings of the tenth annual Governor's conference on the environment: Water

    SciTech Connect

    Not Available

    1986-01-01

    This book contains 35 papers. Some of the titles are: Effects of Acid Rain on Aquatic Exosystems; Acid Rain Research in Kentucky; Blasting Effects on Water Wells and Ground Water; Groundwater Pollution Problems in Kentucky Limestone Areas; and a Private Citizen's Concerns and Ideas Regarding the Environment and Air Pollution Problems of Today.

  13. Ground Water Technical Support Center (GWTSC) Annual Report Fiscal Year 2015

    EPA Science Inventory

    The Ground Water Technical Support Center (GWTSC) is part of the Ground Water and Ecosystems Restoration Division (GWERD), which is based in the Robert S. Kerr Environmental Research Center in Ada, Oklahoma. The GWERD is a research division of U.S. EPA’s National Risk Manag...

  14. Detection limits for real-time source water monitoring using indigenous freshwater microalgae

    SciTech Connect

    Rodriguez Jr, Miguel; Greenbaum, Elias

    2009-01-01

    This research identified toxin detection limits using the variable fluorescence of naturally occurring microalgae in source drinking water for five chemical toxins with different molecular structures and modes of toxicity. The five chemicals investigated were atrazine, Diuron, paraquat, methyl parathion, and potassium cyanide. Absolute threshold sensitivities of the algae for detection of the toxins in unmodified source drinking water were measured. Differential kinetics between the rate of action of the toxins and natural changes in algal physiology, such as diurnal photoinhibition, are significant enough that effects of the toxin can be detected and distinguished from the natural variance. This is true even for physiologically impaired algae where diminished photosynthetic capacity may arise from uncontrollable external factors such as nutrient starvation. Photoinhibition induced by high levels of solar radiation is a predictable and reversible phenomenon that can be dealt with using a period of dark adaption of 30 minutes or more.

  15. Dissociation constants of parabens and limiting conductances of their ions in water.

    PubMed

    Kroflič, Ana; Apelblat, Alexander; Bešter-Rogač, Marija

    2012-02-02

    Precise measurements of electrical conductivities of methylparaben, ethylparaben, propylparaben, and butylparaben sodium salts in dilute aqueous solutions were performed from 278.15 to 313.15 K in 5 K intervals. Experimental conductivity data were analyzed applying the Quint-Viallard conductivity equations by taking into account the salt hydrolysis in aqueous solutions. These evaluations yield the limiting conductances of paraben anions and the dissociation constants of the investigated parabens in water. From temperature dependence of dissociation constants, the thermodynamic functions associated with the dissociation process were estimated. It was discovered that the contributions of enthalpy and entropy to the Gibbs free energy are quite similar. The Walden products of paraben anions in water are independent of temperature, indicating that the hydrodynamic radii are not significantly affected by temperature.

  16. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon, Annual Report 2001.

    SciTech Connect

    Hemmingsen, Alan R.; Gunckel, Stephanie L.; Sankovich, Paul M.; Howell, Philip J.

    2002-12-01

    Bull trout Salvelinus confluentus exhibit a number of life history strategies. Stream-resident bull trout complete their life cycle in their natal tributaries. Migratory bull trout spawn in tributary streams where juvenile fish usually spend from one to four years before migrating to either a larger river (fluvial) or lake (adfluvial) where they rear before returning to the tributary stream to spawn (Fraley and Shepard 1989). These migratory forms occur where conditions allow movement from spawning locations to downstream waters that provide greater foraging opportunities (Dunham and Rieman 1999). Resident and migratory forms may occur together, and either form can produce resident or migratory offspring (Rieman and McIntyre 1993). The ability to migrate is important to the persistence of local bull trout populations (Rieman and McIntyre 1993). The identification of migratory corridors can help focus habitat protection efforts. Determining the life history form(s) that comprise local populations, the timing of seasonal movements, and the geographic extent of these movements are critical to bull trout protection and recovery efforts. This section describes work accomplished in 2001 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In the Grande Ronde and Walla Walla basins, we continued to monitor the movements of bull trout with radio transmitters applied in 1998 (Hemmingsen, Bellerud, Gunckel and Howell 2001) and 1999 (Hemmingsen, Gunckel

  17. Stream water temperature limits occupancy of salamanders in mid-Atlantic protected areas

    USGS Publications Warehouse

    Grant, Evan H. Campbell; Wiewel, Amber N. M.; Rice, Karen C.

    2014-01-01

    Stream ecosystems are particularly sensitive to urbanization, and tolerance of water-quality parameters is likely important to population persistence of stream salamanders. Forecasted climate and landscape changes may lead to significant changes in stream flow, chemical composition, and temperatures in coming decades. Protected areas where landscape alterations are minimized will therefore become increasingly important for salamander populations. We surveyed 29 streams at three national parks in the highly urbanized greater metropolitan area of Washington, DC. We investigated relationships among water-quality variables and occupancy of three species of stream salamanders (Desmognathus fuscus, Eurycea bislineata, and Pseudotriton ruber). With the use of a set of site-occupancy models, and accounting for imperfect detection, we found that stream-water temperature limits salamander occupancy. There was substantial uncertainty about the effects of the other water-quality variables, although both specific conductance (SC) and pH were included in competitive models. Our estimates of occupancy suggest that temperature, SC, and pH have some importance in structuring stream salamander distribution.

  18. Do water-limiting conditions predispose Norway spruce to bark beetle attack?

    PubMed Central

    Netherer, Sigrid; Matthews, Bradley; Katzensteiner, Klaus; Blackwell, Emma; Henschke, Patrick; Hietz, Peter; Pennerstorfer, Josef; Rosner, Sabine; Kikuta, Silvia; Schume, Helmut; Schopf, Axel

    2015-01-01

    Drought is considered to enhance susceptibility of Norway spruce (Picea abies) to infestations by the Eurasian spruce bark beetle (Ips typographus, Coleoptera: Curculionidae), although empirical evidence is scarce. We studied the impact of experimentally induced drought on tree water status and constitutive resin flow, and how physiological stress affects host acceptance and resistance. We established rain-out shelters to induce both severe (two full-cover plots) and moderate (two semi-cover plots) drought stress. In total, 18 sample trees, which were divided equally between the above treatment plots and two control plots, were investigated. Infestation was controlled experimentally using a novel ‘attack box’ method. Treatments influenced the ratios of successful and defended attacks, but predisposition of trees to infestation appeared to be mainly driven by variations in stress status of the individual trees over time. With increasingly negative twig water potentials and decreasing resin exudation, the defence capability of the spruce trees decreased. We provide empirical evidence that water-limiting conditions impair Norway spruce resistance to bark beetle attack. Yet, at the same time our data point to reduced host acceptance byI. typographus with more extreme drought stress, indicated by strongly negative pre-dawn twig water potentials. PMID:25417785

  19. Do water-limiting conditions predispose Norway spruce to bark beetle attack?

    PubMed

    Netherer, Sigrid; Matthews, Bradley; Katzensteiner, Klaus; Blackwell, Emma; Henschke, Patrick; Hietz, Peter; Pennerstorfer, Josef; Rosner, Sabine; Kikuta, Silvia; Schume, Helmut; Schopf, Axel

    2015-02-01

    Drought is considered to enhance susceptibility of Norway spruce (Picea abies) to infestations by the Eurasian spruce bark beetle (Ips typographus, Coleoptera: Curculionidae), although empirical evidence is scarce. We studied the impact of experimentally induced drought on tree water status and constitutive resin flow, and how physiological stress affects host acceptance and resistance. We established rain-out shelters to induce both severe (two full-cover plots) and moderate (two semi-cover plots) drought stress. In total, 18 sample trees, which were divided equally between the above treatment plots and two control plots, were investigated. Infestation was controlled experimentally using a novel 'attack box' method. Treatments influenced the ratios of successful and defended attacks, but predisposition of trees to infestation appeared to be mainly driven by variations in stress status of the individual trees over time. With increasingly negative twig water potentials and decreasing resin exudation, the defence capability of the spruce trees decreased. We provide empirical evidence that water-limiting conditions impair Norway spruce resistance to bark beetle attack. Yet, at the same time our data point to reduced host acceptance by I. typographus with more extreme drought stress, indicated by strongly negative pre-dawn twig water potentials.

  20. Performance improvement of raw water pretreatment process with pre-inoculation biofilm: feasibility and limiting factors.

    PubMed

    Yang, Guang-Feng; Feng, Li-Juan; Guo, Cai-Rong; Xia, Tian; Xu, Xiang-Yang; Zhu, Liang

    2017-02-01

    The initial formation of biofilm and the removal performance of pollutants in biological pretreatment process for polluted raw water were limited due to the oligotrophic niche in raw water. In this study, the feasibility of using pre-inoculation biofilm formed under nutrients enhanced condition for polluted raw water treatment was analyzed in nine batch reactors. Results showed that the pollutants removal performance of biofilm was improved under nutrients enhanced conditions. Ammonia oxidation rate (AOR) was exponentially increased with the increasing in NH4(+)-N levels, and organic matter removal rate (ORR) was positively related to the initial total organic carbon (TOC) concentration. The biofilm formation and microbial diversity were further improved via adding more substrates, seeding river sediment and feeding effluent from a mature biofilm reactor. However, the biofilm formed under higher substrate conditions had higher half-saturation constant values (K S) to both NH4(+)-N and TOC, which decreased AOR and ORR values when it was used to treat polluted raw water. The reduction percentage of AOR and ORR showed logarithmic growth modes with the increase in K S values. Fortunately, improvement of nutrients flux via accelerating influent replacement could enhance the start-up performance effectively and decrease the operation risk introduced by the changes in substrate affinity.

  1. Limiting activity coefficients of some aromatic and aliphatic nitro compounds in water

    SciTech Connect

    Benes, M.; Dohnal, V.

    1999-09-01

    Limiting activity coefficients of nine nitroaromatic compounds and four nitroalkanes in water were determined in the range of environmentally related temperatures by measuring suitable phase equilibria. For liquid and solid nitroaromatics (nitrobenzene, 2-nitrotoluene, 3-nitrotoluene, 4-nitrotoluene, 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 1-chloro-2-nitrobenzene, and 1-chloro-4-nitrobenzene) the aqueous solubilities were measured by a conventional batch contacting method with UV spectrophotometric analysis, while for nitroalkanes (nitromethane, nitroethane, 1-nitropropane, and 2-nitropropane) the air-water partitioning (Henry`s law constant H{sub 12} or air-water partition coefficient K{sub aw}) was determined by the inert gas stripping method employing gas chromatography. Whenever possible, results were compared to literature values. Calculation of H{sub 12} or K{sub aw} for nitroaromatics from the measured solubilities is hindered by the lack of reliable vapor pressure data. On the basis of the temperature dependences of the solubilities measured, the enthalpies of solution at infinite dilution for the nitroaromatics in water were evaluated.

  2. Limitations of HSPF in Simulating Sub-Urban Pollutant Runoff Into Receiving Waters

    NASA Astrophysics Data System (ADS)

    Endreny, T. A.; Hassett, J. M.

    2001-05-01

    The HSPF (Hydrologic Simulation Program - Fortran) model is a U.S. Environmental Protection Agency endorsed mechanistic model for simulating the water quality impact of storm triggered point and non-point source loading. Although HSPF simulates both impervious and pervious hydrologic components of watershed runoff, the model cannot represent important urban transport mechanisms that route pollutants to receiving waters, including storm sewer runoff, spatially variable watertable triggered runoff, and basin-interior trapping of pollutants in vegetative filters and detention basins. These limitations, when revealed in modeling runoff in NYC's sub-urbanized Croton drinking water supply area, were overcome by loosely coupling HSPF with three other runoff models, Storm Water Management Model (SWMM), Hydrologic-Simulation Program - Fortran (HSPF), Program for Predicting Polluted Particle Passage through Pits, Puddles and Ponds (P8), and Topographic-based Land Atmosphere Transfer Scheme (TOPLATS). Combined, these four models simulate the following transport pathways of concern: 1) impervious processes of catch basin and storm sewer hydraulics, 2) pervious processes of infiltration, surface runoff, sub-surface storm flow, watertable dynamics, and 3) reach and reservoir processes of runoff routing and storm runoff detention. In addition to providing process simulation for investigators, the coupling of these models ultimately enables selection of more appropriate parameter values for a separate set of HSPF model runs that lump the dynamics revealed in the companion models.

  3. Equatorial range limits of an intertidal ectotherm are more linked to water than air temperature.

    PubMed

    Seabra, Rui; Wethey, David S; Santos, António M; Gomes, Filipa; Lima, Fernando P

    2016-10-01

    As climate change is expected to impose increasing thermal stress on intertidal organisms, understanding the mechanisms by which body temperatures translate into major biogeographic patterns is of paramount importance. We exposed individuals of the limpet Patella vulgata Linnaeus, 1758, to realistic experimental treatments aimed at disentangling the contribution of water and air temperature for the buildup of thermal stress. Treatments were designed based on temperature data collected at the microhabitat level, from 15 shores along the Atlantic European coast spanning nearly 20° of latitude. Cardiac activity data indicated that thermal stress levels in P. vulgata are directly linked to elevated water temperature, while high air temperature is only stressful if water temperature is also high. In addition, the analysis of the link between population densities and thermal regimes at the studied locations suggests that the occurrence of elevated water temperature may represent a threshold P. vulgata is unable to tolerate. By combining projected temperatures with the temperature threshold identified, we show that climate change will likely result in the westward expansion of the historical distribution gap in the Bay of Biscay (southwest France), and northward contraction of the southern range limit in south Portugal. These findings suggest that even a minor relaxing of the upwelling off northwest Iberia could lead to a dramatic increase in thermal stress, with major consequences for the structure and functioning of the intertidal communities along Iberian rocky shores.

  4. Annual Storm Water Report for the Y-12 National Security Complex

    SciTech Connect

    Beck, G.S.

    2007-01-01

    The storm water pollution prevention program at the Y-12 National Security Complex consists of two primary elements: sampling and analysis of storm water run-off and routine inspections. When prescribed, the analytical data is compared to a set of cut-off concentration values to determine how the Y-12 Complex relates to other metal fabrication industries in the State of Tennessee. The latest set of inspection results revealed the Y-12 Complex has decreased the potential for storm water pollution by reducing the amount of raw materials, scrap metal and miscellaneous debris exposed to storm water. Future sampling/analysis and inspections are expected to have a continuing positive impact on storm water at the Y-12 Complex.

  5. Annual water-resources review, White Sands Missile Range, New Mexico, 1983

    USGS Publications Warehouse

    Cruz, R.R.

    1984-01-01

    Ground-water data were collected at White Sands Missile Range in 1983. The total amount of water pumped from White Sands Missile Range supply wells in 1983 was 713,557,500 gallons. The Post Headquarters well field accounted for 686,499,200 gallons of the total. Seasonal water-level fluctuations in the supply wells ranged from a 3.00-foot rise in Stallion Range Well-2 (SRC-2) to a 51.00 foot decline in Post headquarters supply well 11 (SW-11). All of the test wells and observation wells up to 2 miles east of the Post Headquarters well field showed a decline for the period 1973-1983. Only one test well and one borehole west of the Post Headquarters well field showed a decline in water level; the other five showed a rise in water level for the period 1973-1983. (USGS)

  6. Design and optimization of a back-flow limiter for the high performance light water reactor

    SciTech Connect

    Fischer, Kai; Laurien, Eckart; Claas, Andreas G.; Schulenberg, Thomas

    2007-07-01

    Design and Analysis of a back-flow limiter are presented, which is implemented as a safety device in the four inlet lines of the Reactor Pressure Vessel (RPV) of the High Performance Light Water Reactor (HPLWR). As a passive component, the back-flow limiter has no moving parts and belongs to the group of fluid diodes. It has low flow resistance for regular operation condition and a high flow resistance when the flow direction is reversed which is the case if a break of the feedwater line occurs. The increased flow resistance is due to a substantially increased swirl for reverse flow condition. The design is optimized employing 1D flow analyses in combination with 3D CFD analyses with respect to geometrical modifications, like the nozzle shape and swirler angles. (authors)

  7. Application of hot melt extrusion for poorly water-soluble drugs: limitations, advances and future prospects.

    PubMed

    Lu, Ming; Guo, Zhefei; Li, Yongcheng; Pang, Huishi; Lin, Ling; Liu, Xu; Pan, Xin; Wu, Chuanbin

    2014-01-01

    Hot melt extrusion (HME) is a powerful technology to enhance the solubility and bioavailability of poorly water-soluble drugs by producing amorphous solid dispersions. Although the number of articles and patents about HME increased dramatically in the past twenty years, there are very few commercial products by far. The three main obstacles limiting the commercial application of HME are summarized as thermal degradation of heat-sensitive drugs at high process temperature, recrystallization of amorphous drugs during storage and dissolving process, and difficulty to obtain products with reproducible physicochemical properties. Many efforts have been taken in recent years to understand the basic mechanism underlying these obstacles and then to overcome them. This article reviewed and summarized the limitations, recent advances, and future prospects of HME.

  8. Unique laminar-flow stability limit based shallow-water theory

    USGS Publications Warehouse

    Chen, Cheng-lung

    1993-01-01

    Two approaches are generally taken in deriving the stability limit for the Froude member (Fs) for laminar sheet flow. The first approach used the Orr-Sommerfeld equation, while the second uses the cross-section-averaged equations of continuity and motion. Because both approaches are based on shallow-water theory, the values of Fs obtained from both approaches should be identical, yet in the literature they are not. This suggests that a defect exists in at least one of the two approaches. After examining the governing equations used in both approaches, one finds that the existing cross-section -averaged equation of motion is dependent on the frame of reference.

  9. Improved methods for water shutoff. Semi-annual report, May 1, 1996--September 30, 1996

    SciTech Connect

    Seright, R.S.

    1997-08-01

    In the United States, more than 20 billion barrels of water are produced each year during oilfield operations. Today, the cost of water disposal is typically between $0.25 and $0.50 per bbl for pipeline transport and $1.50 per bbl for trucked water. Therefore, there is a tremendous economic incentive to reduce water production if that can be accomplished without significantly sacrificing hydrocarbon production. For each 1% reduction in water production, the cost-savings to the oil industry could be between $50,000,000 and $100,000,000 per year. Reduced water production would result directly in improved oil recovery (IOR) efficiency in addition to reduced oil-production costs. A substantial positive environmental impact could also be realized if significant reductions are achieved in the amount of water produced during oilfield operations. In an earlier project, we identified fractures (either naturally or artificially induced) as a major factor that causes excess water production and reduced oil recovery efficiency, especially during waterfloods and IOR projects. We also found fractures to be a channeling and water-production problem that has a high potential for successful treatment by gels and certain other chemical blocking agents. By analogy, these blocking materials also have a high potential for treating narrow channels behind pipe and small casing leaks. We also determined that the ability of blocking agents to reduce permeability to water much more than that to oil is critical to the success of these blocking treatments in production wells if zones are not isolated during placement of the blocking agents.

  10. An upper limit of gaseous water abundance in Chamaeleon-MMS1 as observed with ODIN

    NASA Astrophysics Data System (ADS)

    Klotz, A.; Harju, J.; Ristorcelli, I.; Juvela, M.; Boudet, N.; Haikala, L. K.

    2008-09-01

    Context: The determination of the gaseous water abundances in different intestellar environments is crucial for understanding the oxygen chemistry and its role in the molecular cloud evolution. Aims: The purpose of this study is to estimate water abundance in the protostellar core Cha-MMS1. Methods: The ground-state line of o-H20 at 557 GHz was observed with the ODIN telescope. Two observing runs performed in 2002 and 2003 resulted in an upper limit of TA = 16 mK. A model for the core density and temperature structure was constructed using a 1.3 mm continuum map from SEST/SIMBA. The water abundance profile through the cloud was derived and water line intensities expected from this model were calculated. Results: An upper limit of 7 × 10-9 was derived for the average fractional o-H2O abundance (relative to H{2}). The non-detection is consistent with an abundance profile where a high fractional abundance ( 10-7) is reached in the low-density envelope of the core. According to our radiative transfer calculations, the detection of the 557 GHz line from a quiescent core should severely be hampered by self-absorption. Therefore the present observations do not put hard contrainst on the H2O abundance. Based on observations with Odin, a Swedish-led satellite project funded jointly by the Swedish National Space Board (SNSB), the Canadian Space Agency (CSA), the National Technology Agency of Finland (Tekes) and Centre National d'Étude Spatiale (CNES). The Swedish Space Corporation has been the industrial prime contractor and also is operating the satellite. Complementary data were collected at the European Southern Observatory, La Silla, Chile.

  11. Nitrogen availability impacts oilseed rape (Brassica napus L.) plant water status and proline production efficiency under water-limited conditions.

    PubMed

    Albert, Benjamin; Le Cahérec, Françoise; Niogret, Marie-Françoise; Faes, Pascal; Avice, Jean-Christophe; Leport, Laurent; Bouchereau, Alain

    2012-08-01

    Large amounts of nitrogen (N) fertilizers are used in the production of oilseed rape. However, as low-input methods of crop management are introduced crops will need to withstand temporary N deficiency. In temperate areas, oilseed rape will also be affected by frequent drought periods. Here we evaluated the physiological and metabolic impact of nitrate limitation on the oilseed rape response to water deprivation. Different amounts of N fertilizer were applied to plants at the vegetative stage, which were then deprived of water and rehydrated. Both water and N depletion accelerated leaf senescence and reduced leaf development. N-deprived plants exhibited less pronounced symptoms of wilting during drought, probably because leaves were smaller and stomata were partially closed. Efficiency of proline production, a major stress-induced diversion of nitrogen metabolism, was assessed at different positions along the whole plant axis and related to leaf developmental stage and water status indices. Proline accumulation, preferentially in younger leaves, accounted for 25-85% of the free amino acid pool. This was mainly due to a better capacity for proline synthesis in fully N-supplied plants whether they were subjected to drought or not, as deduced from the expression patterns of the proline metabolism BnP5CS and BnPDH genes. Although less proline accumulated in the oldest leaves, a significant amount was transported from senescing to emerging leaves. Moreover, during rehydration proline was readily recycled. Our results therefore suggest that proline plays a significant role in leaf N remobilization and in N use efficiency in oilseed rape.

  12. Using stable isotopes to characterize differential depth of water uptake based on environmental conditions in perennial biofuel and traditional annual crops

    NASA Astrophysics Data System (ADS)

    Miller, J. N.; Nystrom, R.; Bernacchi, C.

    2013-12-01

    Global climate change related to fossil fuel consumption coupled with the necessity for secure, cost-effective, and renewable domestic energy is continuing to drive the development of a bioenergy industry. Numerous second-generation biofuel crops have been identified that hold promise as sustainable feedstocks for the industry, including perennial grasses that utilize the highly water and energy efficient C4 photosynthetic pathway. Among the perennial grasses, miscanthus (Miscanthus × giganteus) and switchgrass (Panicum virgatum) stand out as having high biomass, minimal maintenance, low nutrient input requirements, and positive environmental benefits. These grasses are able to withstand a wide range of growing season temperatures and precipitation regimes, particularly in reference to the annual row crops that they are likely to replace. During the drought of 2012 traditional row crops suffered major reductions in yield whereas the perennial grasses retained relatively high biomass yields. We hypothesize that this is due to the ability of the perennial grasses to access water from deeper soil water relative to the annual row crops. To test this hypothesis, we use isotopic techniques to determine the soil depth from which the various species obtain water. Data from summer 2013 suggests that the perennial grasses preferentially use surface water when available but can extract water from depths that the annual row crops are unable to reach. These results indicate that perennial grasses, with deeper roots, will likely sustain growth under conditions when annual row crops are unable.

  13. Annual variability of water productivity components in the watershed of Cabeceira Comprida stream, Santa Fé do Sul, Brazil

    NASA Astrophysics Data System (ADS)

    Coaguila, Daniel N.; Hernandez, Fernando B. T.; de C. Teixeira, Antônio H.; Neale, Christopher M.; Franco, Renato A. M.; Leivas, Janice F.

    2016-10-01

    The Cabeceira Comprida stream's watershed, located in Santa Fé do Sul, Brazil, is an agroecosystem with great demand of water for the population and agriculture. During the dry season the water demand exceeds the amount generated by the watershed. It is important to know the dynamics of the water above the ground to improve the water resources management. Ten Landsat 8 images were used combined with Northwestern São Paulo State Weather Network data under different thermohydrological conditions of the year 2014 to quantify actual evapotranspiration (ETa), biomass production (BIO) and water productivity (WP) based on ETa. Using the Simple Algorithm for Retrieving evapotranspiration (SAFER) for calculating ETa, the Monteith's radiation model was applied for estimating the BIO and for calculation of WP the ratio of BIO and ETa. The average pixels for ETa, BIO and WP ranged respectively from 0.38 +/- 0.35 to 2.05 +/- 0.76 mm day-1; 10.15 +/- 12.19 to 71.61 +/- 35.54 kg ha-1 day-1; 1.89 +/- 0.76 to 3.88 +/- 0.86 kg m-3. The lower values of ETa (0.38 mm day-1; DOY 220), BIO (10.15 kg ha-1 day-1; DOY 220) and WP (1.89 kg m-3; DOY 204) were obtained in winter, and highest values of ETa (2.05 mm day-1; DOY 364) and BIO (71.64 kg ha-1 day-1; DOY 364) in the summer and WP (3.88 kg m-3; DOY 92) in the autumn. The water productivity components can subsidize the monitoring of the agro-ecosystems, being a useful tool to quantify the annual variability of ETa and BIO.

  14. Evaporation, transpiration, and ecosystem water use efficiency in a multi-annual sugarcane production system in Hawai'i, USA

    NASA Astrophysics Data System (ADS)

    Anderson, R. G.; Tirado-corbala, R.; Wang, D.; Ayars, J. E.

    2013-12-01

    Food and biofuel production will require practices that increase water use efficiency in order to have future sustainability in a water-constrained environment. One possible practice is the use of food and energy crops with multi-annual growing periods, which could reduce bare soil evaporation. We integrated field water budgets, micrometeorology, and plant sampling to observe plant growth and evapotranspiration (ET) in two sugarcane (Saccharum officinarum L.) fields in Hawai'i, USA in contrasting environments with unusually long (18-24 month) growing periods. We partitioned observed ET into evaporation and transpiration using a flux partitioning model and calculated ecosystem water use efficiency (EWUE=Net Ecosystem Productivity/ET) and harvest WUE (HWUE=Aboveground Net Ecosystem Productivity/ET) to assess sugarcane water use efficiency. After the start of the mid-period, our higher elevation, less windy field ('Lee') had a slightly higher mean EWUE (31.5 kg C ha-1 mm-1) than our lower elevation, windier ('Windy') field (mean EWUE of 30.7 kg C ha-1 mm-1). HWUE was also very high (HWUE >27 kg C ha-1 mm-1) in both fields due to aboveground biomass composing >87% of total biomass. Transpiration, as a fraction of total ET, increased rapidly with canopy cover in both fields; during the mid-period, transpiration was an average of 84% of total ET in Windy and 80% in Lee, with Lee showing greater variation than Windy. As expected, daily EWUE increased with canopy cover during the initial growing stages; more significantly, EWUE showed no substantial decrease during the 2nd year with an aging crop. The results illustrate the potential for longer-rotation crop cycles for increasing water use efficiency, particularly in tropical regions.

  15. Evaluation of Management of Water Releases for Painted Rocks Rexervoir, Bitterroot River, Montana, 1985 Annual Report.

    SciTech Connect

    Lere, Mark E.

    1985-12-01

    The Bitterroot River, located in western Montana, is an important and heavily used resource, providing water for agriculture and a source for diversified forms of recreation. Water shortages in the river, however, have been a persistent problem for both irrigators and recreational users. Five major diversions and numerous smaller canals remove substantial quantities of water from the river during the irrigation season. Historically, the river has been severely dewatered between the towns of Hamilton and Stevensville as a result of these withdrawals. Demands for irrigation water from the Bitterroot River have often conflicted with the instream flow needs for trout. Withdrawals of water can decrease suitable depths, velocities, substrates and cover utilized by trout (Stalnaker and Arnette 1976, Wesche 1976). Losses in habitat associated with dewatering have been shown to diminish the carrying capacities for trout populations (Nelson 1980). Additionally, dewatering of the Bitterroot River has forced irrigators to dike or channelize the streambed to obtain needed flows. These alterations reduce aquatic habitat and degrade channel stability. Odell (personal communication) found a substantial reduction in the total biomass of aquatic insects within a section of the Bitterroot River that had been bulldozed for irrigation purposes. The Montana Department of Fish, Wildlife and Parks (MDFWP) has submitted a proposal to the Northwest Power Planning Council for the purchase of 10,000 acre-feet (AF) of stored water in Painted Rocks Reservoir to augment low summer flows in the Bitterroot River. This supplemental water potentially would enhance the fishery in the river and reduce degradation of the channel due to diversion activities. The present study was undertaken to: (1) develop an implementable water management plan for supplemental releases from Painted Rocks Reservoir which would provide optimum benefits to the river: (2) gather fisheries and habitat information to

  16. Comprehensive cooling water study annual report. Volume II: introduction and site description, Savannah River Plant

    SciTech Connect

    Gladden, J.B.; Lower, M.W.; Mackey, H.E.; Specht, W.L.; Wilde, E.W.

    1985-07-01

    The Comprehensive Cooling Water Study was initiated in 1983 to evaluate the environmental effecs of the intake and release of cooling water on the structure and function of aquatic ecosystems at the Savannah River Plant. This report presents the results from the first year of the two year study and also summarizes results from previous studies on aquatic ecosystems of the Savannah River Plant. Five major program elements are addressed: water quality, radionuclide and heavy metal transport, wetlands ecology, aquatic ecology, and endangered species. 63 refs., 13 figs., 7 tabs.

  17. Annual water-resources review, White Sands Missile Range, New Mexico

    USGS Publications Warehouse

    Cruz, R.R.

    1982-01-01

    Ground-water data were collected in 1981 at White Sands Missile Range in south-central New Mexico. The total amount of water pumped at White Sands Missile Range was approximately 59 million gallons less than in 1980; however the five supply wells in the Range areas adjacent to the Post Headquarters area produced approximately 16.2 million gallons more in 1981 than in 1980. Depth-to-water measurements in the Post Headquarters supply wells continued to show seasonal declines. (USGS)

  18. Annual Storm Water Report for the Y-12 National Security Complex, Oak Ridge, Tennessee

    SciTech Connect

    Clean Water Compliance Section of the Environment Compliance Department

    2012-01-01

    The storm water pollution prevention program at the Y-12 National Security Complex (Y-12 Complex) intends to protect the quality of storm water runoff through: (1) reducing the exposure of metal accumulation areas to precipitation, (2) implementation of Best Management Practices, (3) sampling during rain events and subsequent analysis, and (4) routine surveillances. When prescribed, the analytical data is compared to a set of cut-off concentration values to determine how the Y-12 Complex relates to other metal fabrication industries in the state of Tennessee. The quality of the storm water exiting the Y-12 Complex via East Fork Poplar Creek indicated some improvement in 2011. This improvement is attributable to the completion of several construction, demolition and remediation projects which occurred in 2010 and 2011. Emphasis will continue to be placed on site inspections and the timely implementation of improved storm water control measures as deemed necessary.

  19. Annual Storm Water Report for the Y-12 National Security Complex Oak Ridge, Tennessee

    SciTech Connect

    Environment Compliance Department

    2012-01-01

    The storm water pollution prevention program at the Y-12 National Security Complex (Y-12 Complex) intends to protect the quality of storm water runoff through: (1) reducing the exposure of metal accumulation areas to precipitation, (2) implementation of Best Management Practices, (3) sampling during rain events and subsequent analysis, and (4) routine surveillances. When prescribed, the analytical data is compared to a set of cut-off concentration values to determine how the Y-12 Complex relates to other metal fabrication industries in the state of Tennessee. The quality of the storm water exiting the Y-12 Complex via East Fork Poplar Creek indicated some improvement in 2011. This improvement is attributable to the completion of several construction, demolition and remediation projects which occurred in 2010 and 2011. Emphasis will continue to be placed on site inspections and the timely implementation of improved storm water control measures as deemed necessary.

  20. Transport and transfer rates in the waters of the continental shelf. Annual report

    SciTech Connect

    Biscaye, P.E.

    1980-09-01

    The goal of govern project is to understand and quantify the processes that the transport and dispersal of energy-related pollutants introduced to the waters of the continental shelf and slope. The report is divided into sections dealing with processes associated with suspended solids; processes associated with sediments sinks for radionuclides and other pollutants; and spreading of water characteristics and species in solution. (ACR)

  1. Stocking of Offsite Waters for Hungry Horse Dam Mitigation; Creston National Fish Hatchery, 2002-2003 Annual Report.

    SciTech Connect

    US Fish and Wildlife Service Staff,

    2004-02-01

    Mitigation Objective 1: Produce Native Westslope Cutthroat Trout at Creston NFH--Task: Acquire eggs and rear up to 100,000 Westslope Cutthroat trout annually for offsite mitigation stocking. Accomplishments: A total of 141,000 westslope cutthroat eggs (M012 strain) was acquired from the State of Montana Washoe Park State Fish Hatchery in May 2002 for this objective. We also received an additional 22,000 westslope cutthroat eggs, MO12 strain naturalized, from feral fish at Rogers Lake, Flathead County, Montana. The fish were reared using approved fish culture techniques as defined in the U.S. Fish and Wildlife Service, Fish Hatchery Management guidelines. Survival from the swim up fry stage to stocking was 95.6%. We achieved a 0.80 feed conversion this year on a new diet, Skretting ''Nutra Plus''. Post release survival and angler success is monitored annually by Montana Fish Wildlife and Parks (MFWP) and the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations vary yearly based on results of biological monitoring and adaptive management. Mitigation Objective 2: Produce Rainbow Trout at Creston NFH--Task: Acquire and rear up to 100,000 Rainbow trout annually for offsite mitigation in closed basin waters. Accomplishments: A total of 54,000 rainbow trout eggs (Arlee strain) was acquired from the Ennis National Fish Hatchery in December 2002 for this objective. The fish were reared using approved fish culture techniques as defined in the U.S. Fish and Wildlife Service, Fish Hatchery Management guidelines. Survival from the swim up fry stage to stocking was 99.9%. We achieved a 0.79 feed conversion this year on a new diet, Skretting ''Nutra Plus''. Arlee rainbow trout are being used for this objective because the stocking locations are terminal basin reservoirs and habitat conditions and returns to the creel are unsuitable for native cutthroat. Post release survival and angler success is monitored annually by the Confederated Salish and Kootenai

  2. Limitations of ichnofossil approach for evaluating paleo-bottom-water redox conditions

    SciTech Connect

    Savrda, C.E.; Bottjer, D.

    1987-05-01

    Information on trace fossil diversity, burrow size, and depth of burrow penetration has been incorporated into an ichnofossil tiering model designed for the evaluation of paleo-bottom-water redox conditions. Previous applications to a variety of Phanerozoic strata indicate that this trace fossil approach is more effective than previously emphasized criteria for reconstructing relative degree of oxygenation as well as rates and magnitudes of temporal change in oxygenation. However, the trace fossil model is not without limitations. Presently, they recognize four factors that could limit the accuracy of ichnology-based redox reconstructions: (1) information loss - increases in penetration depth (associated with reoxygenation) that occur at rates in excess of sedimentation rate will destroy a portion of the previous record of oxygenation whereas extended residence times of deep-tier organisms may mask the record through excessive overprinting; (2) inadequate structure visibility - required information on trace fossil assemblage composition and cross cutting relationships is unobtainable for strata where original or diagenetically enhanced contrast between burrows and surrounding sediments is lacking; (3) complexity introduced by rapid deposition - periodic turbidite deposition can mask the desired oxygen signal through substrate modification, temporary modification of faunal composition and behavior, and/or temporary water chemistry changes; and (4) changes in substrate consistency - temporal variation in substrate stiffness (e.g., development of firmgrounds) may result in intrastratal variation in trace fossil tiering structure. The success of future applications of the ichnologic approach depends upon thorough consideration of these factors.

  3. CO2 fluxes at northern fens and bogs have opposite responses to inter-annual fluctuations in water table

    NASA Astrophysics Data System (ADS)

    Sulman, Benjamin N.; Desai, Ankur R.; Saliendra, Nicanor Z.; Lafleur, Peter M.; Flanagan, Lawrence B.; Sonnentag, Oliver; Mackay, D. Scott; Barr, Alan G.; van der Kamp, Garth

    2010-10-01

    This study compares eddy-covariance measurements of carbon dioxide fluxes at six northern temperate and boreal peatland sites in Canada and the northern United States of America, representing both bogs and fens. The two peatland types had opposite responses of gross ecosystem photosynthesis (GEP) and ecosystem respiration (ER) to inter-annual fluctuations in water table level. At fens, wetter conditions were correlated with lower GEP and ER, while at bogs wetter conditions were correlated with higher GEP and ER. We hypothesize that these contrasting responses are due to differences in the relative contributions of vascular plants and mosses. The coherence of our results between sites representing a range of average environmental conditions indicates ecosystem-scale differences in resilience to hydrological changes that should be taken into account when considering the future of peatland ecosystem services such as carbon sequestration under changing environmental conditions.

  4. Enhancement of nitrogen and phosphorus removal from eutrophic water by economic plant annual ryegrass (Lolium multiflorum) with ion implantation.

    PubMed

    Li, Miao; Sheng, Guo-ping; Wu, Yue-jin; Yu, Zeng-liang; Bañuelos, Gary S; Yu, Han-qing

    2014-01-01

    Severe eutrophication of surface water has been a major problem of increasing environmental concern worldwide. In the present study, economic plant annual ryegrass (Lolium multiflorum) was grown in floating mats as an economic plant-based treatment system to evaluate its potential after ion implantation for removing nutrients in simulated eutrophic water. The specific weight growth rate of L. multiflorum with ion implantation was significantly greater than that of the control, and the peroxidase, nitrate reductase, and acid phosphatase activities of the irradiated L. multiflorum were found to be greater than those plants without ion implantation. Higher total nitrogen (TN) and total phosphorus (TP) removal efficiencies were obtained for the L. multiflorum irradiated with 25 keV 5.2 × 10(16) N(+) ions/cm(2) and 30 keV 4.16 × 10(16) N(+) ions/cm(2), respectively (p < 0.05). Furthermore, the nitrogen and phosphorus contents in the plant biomass with ion implantation were also greater than those in the control and were positively correlated with TN and TP supplied. L. multiflorum itself was directly responsible for 39-49 and 47-58 % of the overall N and P removal in the experiment, respectively. The research results suggested that ion implantation could become a promising approach for increasing phytoremediation efficiency of nutrients from eutrophic water by L. multiflorum.

  5. Improved methods for water shutoff. Annual report, October 1, 1996--September 30, 1997

    SciTech Connect

    Seright, R.S.

    1997-11-01

    In the US, more than 20 billion barrels of water are produced each year during oilfield operations. There is a tremendous economic incentive to reduce water production if that can be accomplished without significantly sacrificing hydrocarbon production. In an earlier project, the authors determined that the ability of blocking agents to reduce permeability to water much more than that to oil is critical to the success of these blocking treatments in production wells if zones are not protected during placement of the blocking agent. This research project has three objectives: (1) to identify chemical blocking agents that will during placement, flow readily through fractures without penetrating significantly into porous rock and without screening out or developing excessive pressure gradients and at a predictable and controllable time, become immobile and resist breakdown upon exposure to moderate to high pressure gradients; (2) to identify schemes that optimize placement of blocking agents; and (3) to explain why gels and other chemical blocking agents reduce permeability to one phase (e.g., water) more than that of another phase (e.g., oil or gas). Chapter 2 examines the validity of using water/oil ratio plots to distinguish between coning and channeling water production mechanisms. Chapter 3 develops a method to size gelant treatments in hydraulically fractured production wells. Chapter 4 identifies characteristics of naturally fractured reservoirs where gel treatments have the greatest potential. Chapter 5 reports experimental results from studies of gel properties in fractures. Finally, Chapter 6, the authors investigate the mechanism responsible for gels reducing the permeability to water more than that to oil.

  6. The terrestrial green macroalga Prasiola calophylla (Trebouxiophyceae, Chlorophyta): ecophysiological performance under water-limiting conditions.

    PubMed

    Holzinger, Andreas; Herburger, Klaus; Blaas, Kathrin; Lewis, Louise A; Karsten, Ulf

    2017-01-09

    The phylogenetic placement of Prasiola calophylla, from an anthropogenic habitat previously shown to contain a novel UV sunscreen compound, was confirmed by analysis of its rbcL gene. This alga has the capacity to tolerate strong water-limiting conditions. The photosynthetic performance and ultrastructural changes under desiccation and osmotic stress were investigated. Freshly harvested thalli showed an effective quantum yield of PSII [Y(II)] of 0.52 ± 0.06 that decreased to ∼60% of the initial value at 3000 mM sorbitol, and 4000 mM sorbitol led to a complete loss of Y(II). The Y(II) of thalli exposed to controlled desiccating conditions at 60% relative humidity (RH) ceased within 240 min, whereas zero values were reached after 120 min at 20% RH. All investigated samples completely recovered Y(II) within ∼100 min after rehydration. Relative electron transport rates (rETR) were temperature dependent, increasing from 5, 10, to 25 °C but strongly declining at 45 °C. Transmission electron microscopy of samples desiccated for 2.5 h showed an electron dense appearance of the entire cytoplasm when compared to control samples. Thylakoid membranes were still visible in desiccated cells, corroborating the ability to recover. Control and desiccated cells contained numerous storage lipids and starch grains, providing reserves. Overall, P. calophylla showed a high capacity to cope with water-limiting conditions on a physiological and structural basis. A lipophilic outer layer of the cell walls might contribute to reduce water evaporation in this poikilohydric organism.

  7. Synthesis of monthly and annual streamflow records (water years 1950-2003) for Big Sandy, Clear, Peoples, and Beaver Creeks in the Milk River basin, Montana

    USGS Publications Warehouse

    Parrett, Charles

    2006-01-01

    To address concerns expressed by the State of Montana about the apportionment of water in the St. Mary and Milk River basins between Canada and the United States, the International Joint Commission requested information from the United States government about water that originates in the United States but does not cross the border into Canada. In response to this request, the U.S. Geological Survey synthesized monthly and annual streamflow records for Big Sandy, Clear, Peoples, and Beaver Creeks, all of which are in the Milk River basin in Montana, for water years 1950-2003. This report presents the synthesized values of monthly and annual streamflow for Big Sandy, Clear, Peoples, and Beaver Creeks in Montana. Synthesized values were derived from recorded and estimated streamflows. Statistics, including long-term medians and averages and flows for various exceedance probabilities, were computed from the synthesized data. Beaver Creek had the largest median annual discharge (19,490 acre-feet), and Clear Creek had the smallest median annual discharge (6,680 acre-feet). Big Sandy Creek, the stream with the largest drainage area, had the second smallest median annual discharge (9,640 acre-feet), whereas Peoples Creek, the stream with the second smallest drainage area, had the second largest median annual discharge (11,700 acre-feet). The combined median annual discharge for the four streams was 45,400 acre-feet. The largest combined median monthly discharge for the four creeks was 6,930 acre-feet in March, and the smallest combined median monthly discharge was 48 acre-feet in January. The combined median monthly values were substantially smaller than the average monthly values. Overall, synthesized flow records for the four creeks are considered to be reasonable given the prevailing climatic conditions in the region during the 1950-2003 base period. Individual estimates of monthly streamflow may have large errors, however. Linear regression was used to relate

  8. Credibility theory based dynamic control bound optimization for reservoir flood limited water level

    NASA Astrophysics Data System (ADS)

    Jiang, Zhiqiang; Sun, Ping; Ji, Changming; Zhou, Jianzhong

    2015-10-01

    The dynamic control operation of reservoir flood limited water level (FLWL) can solve the contradictions between reservoir flood control and beneficial operation well, and it is an important measure to make sure the security of flood control and realize the flood utilization. The dynamic control bound of FLWL is a fundamental key element for implementing reservoir dynamic control operation. In order to optimize the dynamic control bound of FLWL by considering flood forecasting error, this paper took the forecasting error as a fuzzy variable, and described it with the emerging credibility theory in recent years. By combining the flood forecasting error quantitative model, a credibility-based fuzzy chance constrained model used to optimize the dynamic control bound was proposed in this paper, and fuzzy simulation technology was used to solve the model. The FENGTAN reservoir in China was selected as a case study, and the results show that, compared with the original operation water level, the initial operation water level (IOWL) of FENGTAN reservoir can be raised 4 m, 2 m and 5.5 m respectively in the three division stages of flood season, and without increasing flood control risk. In addition, the rationality and feasibility of the proposed forecasting error quantitative model and credibility-based dynamic control bound optimization model are verified by the calculation results of extreme risk theory.

  9. Growth decline linked to warming-induced water limitation in hemi-boreal forests.

    PubMed

    Wu, Xiuchen; Liu, Hongyan; Guo, Dali; Anenkhonov, Oleg A; Badmaeva, Natalya K; Sandanov, Denis V

    2012-01-01

    Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal forests, based on ring width measurements from three dominant tree-species (Pinus sylvestris, Larix sibirica and Larix gmelinii), sampled from eight sites in the region. We found that regional tree growth has become increasingly limited by low soil water content in the pre- and early-growing season (from October of the previous year to July of the current year) over the past 80 years. A warming-induced reduction in soil water content has also increased the climate sensitivity of these three tree species. Beginning in the mid-1980s, a clear decline in growth is evident for both the pine forests and the larch forests, although there are increasing trends in the proxy of soil water use efficiencies. Our findings are consistent with those from other parts of the world and provide valuable insights into the regional carbon cycle and vegetation dynamics, and should be useful for devising adaptive forest management strategies.

  10. Growth Decline Linked to Warming-Induced Water Limitation in Hemi-Boreal Forests

    PubMed Central

    Wu, Xiuchen; Liu, Hongyan; Guo, Dali; Anenkhonov, Oleg A.; Badmaeva, Natalya K.; Sandanov, Denis V.

    2012-01-01

    Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal forests, based on ring width measurements from three dominant tree-species (Pinus sylvestris, Larix sibirica and Larix gmelinii), sampled from eight sites in the region. We found that regional tree growth has become increasingly limited by low soil water content in the pre- and early-growing season (from October of the previous year to July of the current year) over the past 80 years. A warming-induced reduction in soil water content has also increased the climate sensitivity of these three tree species. Beginning in the mid-1980s, a clear decline in growth is evident for both the pine forests and the larch forests, although there are increasing trends in the proxy of soil water use efficiencies. Our findings are consistent with those from other parts of the world and provide valuable insights into the regional carbon cycle and vegetation dynamics, and should be useful for devising adaptive forest management strategies. PMID:22916142

  11. Microbial response to limited nutrients in shallow water immediately after the end-Permian mass extinction.

    PubMed

    Jia, C; Huang, J; Kershaw, S; Luo, G; Farabegoli, E; Perri, M C; Chen, L; Bai, X; Xie, S

    2012-01-01

    Previous work indicates that a variety of microbes bloomed in the oceans after the end-Permian faunal mass extinction, but evidence is sporadically documented. Thus, the nature and geographic distribution of such microbes and their associations are unclear, addressed in this study using a series of biomarker groups. On the basis of microbial biomarker records of the 2-methylhopane index, evidence is presented for cyanobacterial blooms in both the western and eastern Tethys Sea and in both shallow and deep waters, after the mass extinction. The enhanced relative abundance of C(28) (expressed by the C(28) /C(29) ratio of) regular steranes suggests a bloom of prasinophyte algae occurred immediately after the end-Permian faunal extinction, comparable with those observed in some other mass extinctions in Phanerozoic. Significantly, cyanobacteria and prasinophyte algae show a synchronized onset of bloom in the shallow water Bulla section, north Italy, inferring for the first time their coupled response to the biotic crisis and the associated environmental conditions. However, in Meishan of Zhejiang Province in south China, the bloom declined earlier than in Bulla. The association of increased 2-methylhopane index with a negative shift in the nitrogen isotope composition infers a scenario of enhanced nitrogen fixation by cyanobacteria immediately after the faunal mass extinction. N(2) fixation by cyanobacteria is here interpreted to have provided prasinophyte algae with ammonium in nutrient-limited shallow waters, and thus caused their associated blooms.

  12. Does limited data availability prevent adequate water use estimates on farm scale?

    NASA Astrophysics Data System (ADS)

    Kayatz, Benjamin; Kuster, Benjamin; Percy, Barbara; Hillier, Jonathan; Freese, Dirk; Wattenbach, Martin

    2015-04-01

    Increasing food production for a growing world population and at the same time mitigating climate change as well as adapting to its consequences is one of the key global challenges. Therefore producing crops with fewer resources such as water and fertilizers and less emissions of greenhouse gases is an important question that has to be answered on farm scale. The cool farm tool (CFT) is a farm scale emission calculator and was developed in 2010 to help farmers to reduce their carbon footprint. In order to adapt to future climate change an easy to use and at the same time robust water footprinting tool is needed for the CFT to take a more holistic approach on environmental sustainability. However data on farm level is often scarce. We investigated the effect of limited data on actual evapotranspiration using the FAO56 standard to assess the quality of farm water footprint estimates. Calculations are based on various agricultural sites from the Fluxnet database and estimates are compared to eddy covariance measurements. Results show that higher data availability is not directly linked to more accurate estimates of actual evapotranspiration. Estimates based only on temperature and relative humidity are still able to reproduce daily patterns. However cumulative values over one growing season show a considerable offset to eddy covariance observations for all data input levels. Finding the optimum between data requirements and an accuracy that fulfills farmer needs is crucial. Engagement of farmers and using a global network as the Fluxnet database will help to achieve this goal.

  13. Opportunities and limitations of molecular methods for quantifying microbial compliance parameters in EU bathing waters.

    PubMed

    Oliver, David M; van Niekerk, Melanie; Kay, David; Heathwaite, A Louise; Porter, Jonathan; Fleming, Lora E; Kinzelman, Julie L; Connolly, Elaine; Cummins, Andy; McPhail, Calum; Rahman, Amanna; Thairs, Ted; de Roda Husman, Ana Maria; Hanley, Nick D; Dunhill, Ian; Globevnik, Lidija; Harwood, Valerie J; Hodgson, Chris J; Lees, David N; Nichols, Gordon L; Nocker, Andreas; Schets, Ciska; Quilliam, Richard S

    2014-03-01

    The debate over the suitability of molecular biological methods for the enumeration of regulatory microbial parameters (e.g. Faecal Indicator Organisms [FIOs]) in bathing waters versus the use of traditional culture-based methods is of current interest to regulators and the science community. Culture-based methods require a 24-48hour turn-around time from receipt at the laboratory to reporting, whilst quantitative molecular tools provide a more rapid assay (approximately 2-3h). Traditional culturing methods are therefore often viewed as slow and 'out-dated', although they still deliver an internationally 'accepted' evidence-base. In contrast, molecular tools have the potential for rapid analysis and their operational utility and associated limitations and uncertainties should be assessed in light of their use for regulatory monitoring. Here we report on the recommendations from a series of international workshops, chaired by a UK Working Group (WG) comprised of scientists, regulators, policy makers and other stakeholders, which explored and interrogated both molecular (principally quantitative polymerase chain reaction [qPCR]) and culture-based tools for FIO monitoring under the European Bathing Water Directive. Through detailed analysis of policy implications, regulatory barriers, stakeholder engagement, and the needs of the end-user, the WG identified a series of key concerns that require critical appraisal before a potential shift from culture-based approaches to the employment of molecular biological methods for bathing water regulation could be justified.

  14. Annual precipitation regulates spatial and temporal drivers of lake water clarity.

    PubMed

    Rose, Kevin C; Greb, Steven R; Diebel, Matthew; Turner, Monica G

    2017-03-01

    Understanding how and why lakes vary and respond to different drivers through time and space is needed to understand, predict, and manage freshwater quality in an era of rapidly changing land use and climate. Water clarity regulates many characteristics of aquatic ecosystems and is responsive to watershed features, making it a sentinel of environmental change. However, whether precipitation alters the relative importance of features that influence lake water clarity or the spatial scales at which they operate is unknown. We used a data set of thousands of northern temperate lakes and asked (1) How does water clarity differ between a very wet vs. dry year? (2) Does the relative importance of different watershed features, or the spatial extent at which they are measured, vary between wet and dry years? (3) What lake and watershed characteristics regulate long-term water clarity trends? Among lakes, water clarity was reduced and less variable in the wet year than in the dry year; furthermore, water clarity was reduced much more in high-clarity lakes during the wet year than in low-clarity lakes. Climate, land use/land cover, and lake morphometry explained most variance in clarity among lakes in both years, but the spatial scales at which some features were important differed between the dry and wet years. Watershed percent agriculture was most important in the dry year, whereas riparian zone percent agriculture (around each lake and upstream features) was most important in the wet year. Between 1991 and 2012, water clarity declined in 23% of lakes and increased in only 6% of lakes. Conductance influenced the direction of temporal trend (clarity declined in lakes with low conductance), whereas the proportion of watershed wetlands, catchment-to-lake-area ratio, and lake maximum depth interacted with antecedent precipitation. Many predictors of water clarity, such as lake depth and landscape position, are features that cannot be readily managed. Given trends of

  15. Hydrogen production by water dissociation using ceramic membranes - annual report for FY 2008.

    SciTech Connect

    Balachandran, U.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Lu, Y.; Park, C. Y.; Picciolo, J. J.; Energy Systems

    2009-03-25

    The objective of this project is to develop dense ceramic membranes that, without using an external power supply or circuitry, can produce hydrogen via coal/coal gas-assisted water dissociation. This project grew from an effort to develop a dense ceramic membrane for separating hydrogen from gas mixtures such as those generated during coal gasification, methane partial oxidation, and water-gas shift reactions. That effort led to the development of various cermet (i.e., ceramic/metal composite) membranes that enable hydrogen production by two methods. In one method, a hydrogen transport membrane (HTM) selectively removes hydrogen from a gas mixture by transporting it through either a mixed protonic/electronic conductor or a hydrogen transport metal. In the other method, an oxygen transport membrane (OTM) generates hydrogen mixed with steam by removing oxygen that is generated through water splitting. This project focuses on the development of OTMs that efficiently produce hydrogen via the dissociation of water. Supercritical boilers offer very high-pressure steam that can be decomposed to provide pure hydrogen by means of OTMs. Oxygen resulting from the dissociation of steam can be used for coal gasification, enriched combustion, or synthesis gas production. Hydrogen and sequestration-ready CO{sub 2} can be produced from coal and steam by using the membrane being developed in this project. Although hydrogen can also be generated by high-temperature steam electrolysis, producing hydrogen by water splitting with a mixed-conducting membrane requires no electric power or electrical circuitry.

  16. Hydrogen production by water dissociation using ceramic membranes. Annual report for FY 2009.

    SciTech Connect

    Balachandran, U.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Lu, Y.; Park, C. Y.; Picciolo, J. J.; Energy Systems

    2010-04-20

    The objective of this project is to develop dense ceramic membranes that can produce hydrogen via coal/coal gas-assisted water dissociation without using an external power supply or circuitry. This project grew from an effort to develop a dense ceramic membrane for separating hydrogen from gas mixtures such as those generated during coal gasification, methane partial oxidation, and water-gas shift reactions. That effort led to the development of various cermet (i.e., ceramic/metal composite) membranes that enable hydrogen production by two methods. In one method, a hydrogen transport membrane selectively removes hydrogen from a gas mixture by transporting it through either a mixed protonic/electronic conductor or a hydrogen transport metal. In the other method, an oxygen transport membrane (OTM) generates hydrogen mixed with steam by removing oxygen that is generated through water splitting. This project focuses on the development of OTMs that efficiently produce hydrogen via the dissociation of water. Supercritical boilers offer very high-pressure steam that can be decomposed to provide pure hydrogen by means of OTMs. Oxygen resulting from the dissociation of steam can be used for coal gasification, enriched combustion, or synthesis gas production. Hydrogen and sequestration-ready CO{sub 2} can be produced from coal and steam by using the membrane being developed in this project. Although hydrogen can also be generated by high-temperature steam electrolysis, producing hydrogen by water splitting with a mixed-conducting membrane requires no electric power or electrical circuitry.

  17. Hydrogen production by water dissociation using ceramic membranes - annual report for FY 2010.

    SciTech Connect

    Balachandran, U.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Lu, Y.; Park, C. Y.; Picciolo, J. J.

    2011-03-14

    The objective of this project is to develop dense ceramic membranes that can produce hydrogen via coal/coal gas-assisted water dissociation without using an external power supply or circuitry. This project grew from an effort to develop a dense ceramic membrane for separating hydrogen from gas mixtures such as those generated during coal gasification, methane partial oxidation, and water-gas shift reactions. That effort led to the development of various cermet (i.e., ceramic/metal composite) membranes that enable hydrogen production by two methods. In one method, a hydrogen transport membrane (HTM) selectively removes hydrogen from a gas mixture by transporting it through either a mixed protonic/electronic conductor or a hydrogen transport metal. In the other method, an oxygen transport membrane (OTM) generates hydrogen mixed with steam by removing oxygen that is generated through water splitting. This project focuses on the development of OTMs that efficiently produce hydrogen via the dissociation of water. Supercritical boilers offer very high-pressure steam that can be decomposed to provide pure hydrogen using OTMs. Oxygen resulting from the dissociation of steam can be used for coal gasification, enriched combustion, or synthesis gas production. Hydrogen and sequestration-ready CO{sub 2} can be produced from coal and steam by using the membrane being developed in this project. Although hydrogen can also be generated by high-temperature steam electrolysis, producing hydrogen by water splitting with a mixed-conducting membrane requires no electric power or electrical circuitry.

  18. Natural variation, differentiation and genetic tradeoffs of ecophysiological traits in response to water limitation in Brachypodium distachyon and its descendent allotetraploid B. hybridum (Poaceae)

    PubMed Central

    Manzaneda, Antonio J.; Rey, Pedro J.; Anderson, Jill T.; Raskin, Evan; Weiss-Lehman, Christopher; Mitchell-Olds, Thomas

    2015-01-01

    Differences in tolerance to water stress may underlie ecological divergence of closely-related ploidy lineages. However, the mechanistic basis of physiological variation governing eco-geographical cytotype segregation is not well understood. Here, using Brachypodium distachyon and its derived allotetraploid B. hybridum as model, we test the hypothesis that, for heteroploid annuals, ecological divergence of polyploids in drier environments is based on trait differentiation enabling drought-escape. We demonstrate that under water limitation allotetraploids maintain higher photosynthesis and stomatal conductance and show earlier flowering than diploids, concordant with a drought-escape strategy to cope with water stress. Increased heterozygosity, greater genetic variability and plasticity of polyploids could confer a superior adaptive capability. Consistent with these predictions, we document (1) greater standing within-population genetic variation in water use efficiency and flowering time in allotetraploids, and (2) the existence of (non-linear) environmental clines in physiology across allotetraploid populations. Increased gas exchange and diminished WUE occurred at the driest end of the gradient, consistent with a drought-escape strategy. Finally, we found that allotetraploids showed weaker genetic correlations than diploids congruous with the expectation of relaxed pleiotropic constraints in polyploids. Our results suggest evolutionary divergence of ecophysiological traits in each ploidy lineage. PMID:26377138

  19. Natural variation, differentiation, and genetic trade-offs of ecophysiological traits in response to water limitation in Brachypodium distachyon and its descendent allotetraploid B. hybridum (Poaceae).

    PubMed

    Manzaneda, Antonio J; Rey, Pedro J; Anderson, Jill T; Raskin, Evan; Weiss-Lehman, Christopher; Mitchell-Olds, Thomas

    2015-10-01

    Differences in tolerance to water stress may underlie ecological divergence of closely related ploidy lineages. However, the mechanistic basis of physiological variation governing ecogeographical cytotype segregation is not well understood. Here, using Brachypodium distachyon and its derived allotetraploid B. hybridum as model, we test the hypothesis that, for heteroploid annuals, ecological divergence of polyploids in drier environments is based on trait differentiation enabling drought escape. We demonstrate that under water limitation allotetraploids maintain higher photosynthesis and stomatal conductance and show earlier flowering than diploids, concordant with a drought-escape strategy to cope with water stress. Increased heterozygosity and greater genetic variability and plasticity of polyploids could confer a superior adaptive capability. Consistent with these predictions, we document (1) greater standing within-population genetic variation in water-use efficiency (WUE) and flowering time in allotetraploids, and (2) the existence of (nonlinear) environmental clines in physiology across allotetraploid populations. Increased gas exchange and diminished WUE occurred at the driest end of the gradient, consistent with a drought-escape strategy. Finally, we found that allotetraploids showed weaker genetic correlations than diploids congruous with the expectation of relaxed pleiotropic constraints in polyploids. Our results suggest evolutionary divergence of ecophysiological traits in each ploidy lineage.

  20. Experiments on FTU with an actively water cooled liquid lithium limiter

    NASA Astrophysics Data System (ADS)

    Mazzitelli, G.; Apicella, M. L.; Apruzzese, G.; Crescenzi, F.; Iannone, F.; Maddaluno, G.; Pericoli-Ridolfini, V.; Roccella, S.; Reale, M.; Viola, B.; Lyublinski, I.; Vertkov, A.

    2015-08-01

    In order to prevent the overheating of the liquid Li surface and the consequent Li evaporation for T > 500 °C, an advanced version of the liquid lithium limiter has been realized and installed on FTU. This new system, named Cooled Lithium Limiter (CLL), has been optimized to demonstrate the lithium limiter capability to sustain thermal loads as high as 10 MW/m2 with up to 5 s of plasma pulse duration. The CLL operates with an actively cooled system with water circulation at the temperature of about 200 °C, for heating lithium up to the melting point and for the heat removal during the plasma discharges. To characterize CLL during discharges, a fast infrared camera and the spectroscopic signals from Li and D atom emission have been used. The experiments analyzed so far and simulated by ANSYS code, point out that heat loads as high as 2 MW/m2 for 1.5 s have been withstood without problems.

  1. Trends in annual, seasonal, and monthly streamflow characteristics at 227 streamgages in the Missouri River watershed, water years 1960-2011

    USGS Publications Warehouse

    Norton, Parker A.; Anderson, Mark T.; Stamm, John F.

    2014-01-01

    The Missouri River and its tributaries are an important resource that serve multiple uses including agriculture, energy, recreation, and municipal water supply. Understanding historical streamflow characteristics provides relevant guidance to adaptive management of these water resources. Streamflow records in the Missouri River watershed were examined for trends in time series of annual, seasonal, and monthly streamflow. A total of 227 streamgages having continuous observational records for water years 1960–2011 were examined. Kendall’s tau nonparametric test was used to determine statistical significance of trends in annual, seasonal, and monthly streamflow. A trend was considered statistically significant for a probability value less than or equal to 0.10 that the Kendall’s tau value equals zero. Significant trends in annual streamflow were indicated for 101 out of a total of 227 streamgages. The Missouri River watershed was divided into six watershed regions and trends within regions were examined. The western and the southern parts of the Missouri River watershed had downward trends in annual streamflow (56 streamgages), whereas the eastern part of the watershed had upward trends in streamflow (45 streamgages). Seasonal and monthly streamflow trends reflected prevailing annual streamflow trends within each watershed region.

  2. Within-season flowering interruptions are common in the water-limited Sky Islands.

    PubMed

    Crimmins, Theresa M; Bertelsen, David C; Crimmins, Michael A

    2014-05-01

    Within-season breaks in flowering have been reported in a wide range of highly variable ecosystems including deserts, tropical forests and high-elevation meadows. A tendency for interruptions in flowering has also been documented in southwestern US "Sky Island" plant communities, which encompass xeric to mesic conditions. Seasonal breaks in flowering have implications for plant reproductive success, population structure, and gene flow as well as resource availability for pollinators and dependent animals. Most reports of multiple within-season flowering events describe only two distinct flowering episodes. In this study, we set out to better quantify distinct within-season flowering events in highly variable Sky Islands plant communities. Across a >1,200 m elevation gradient, we documented a strong tendency for multiple within-season flowering events. In both distinct spring and summer seasons, we observed greater than two distinct within-season flowering in more than 10 % of instances. Patterns were clearly mediated by the different climate factors at work in the two seasons. The spring season, which is influenced by both temperature and precipitation, showed a mixed response, with the greatest tendency for multiple flowering events occurring at mid-elevations and functional types varying in their responses across the gradient. In the summer season, during which flowering across the gradient is limited by localized precipitation, annual plants exhibited the fewest within-season flowering events and herbaceous perennial plants showed the greatest. Additionally, more distinct events occurred at lower elevations. The patterns documented here provide a baseline for comparison of system responses to changing climate conditions.

  3. Within-season flowering interruptions are common in the water-limited Sky Islands

    NASA Astrophysics Data System (ADS)

    Crimmins, Theresa M.; Bertelsen, C. David; Crimmins, Michael A.

    2014-05-01

    Within-season breaks in flowering have been reported in a wide range of highly variable ecosystems including deserts, tropical forests and high-elevation meadows. A tendency for interruptions in flowering has also been documented in southwestern US "Sky Island" plant communities, which encompass xeric to mesic conditions. Seasonal breaks in flowering have implications for plant reproductive success, population structure, and gene flow as well as resource availability for pollinators and dependent animals. Most reports of multiple within-season flowering events describe only two distinct flowering episodes. In this study, we set out to better quantify distinct within-season flowering events in highly variable Sky Islands plant communities. Across a >1,200 m elevation gradient, we documented a strong tendency for multiple within-season flowering events. In both distinct spring and summer seasons, we observed greater than two distinct within-season flowering in more than 10 % of instances. Patterns were clearly mediated by the different climate factors at work in the two seasons. The spring season, which is influenced by both temperature and precipitation, showed a mixed response, with the greatest tendency for multiple flowering events occurring at mid-elevations and functional types varying in their responses across the gradient. In the summer season, during which flowering across the gradient is limited by localized precipitation, annual plants exhibited the fewest within-season flowering events and herbaceous perennial plants showed the greatest. Additionally, more distinct events occurred at lower elevations. The patterns documented here provide a baseline for comparison of system responses to changing climate conditions.

  4. Ground-water monitoring compliance projects for Hanford Site facilities: Annual progress report for 1987

    SciTech Connect

    Hall, S.H.

    1988-09-01

    This report describes progress during 1987 of five Hanford Site ground water monitoring projects. Four of these projects are being conducted according to regulations based on the federal Resource Conservation and Recovery Act of 1976 and the state Hazardous Waste Management Act. The fifth project is being conducted according to regulations based on the state Solid Waste Management Act. The five projects discussed herein are: 300 Area Process Trenches; 183-H Solar Evaporation Basins; 200 Areas Low-Level Burial Grounds; Nonradioactive Dangerous Waste Landfill; Solid Waste Landfill. For each of the projects, there are included, as applicable, discussions of monitoring well installations, water-table measurements, background and/or downgradient water quality and results of chemical analysis, and extent and rate of movement of contaminant plumes. 14 refs., 30 figs., 13 tabs.

  5. Water resources data for North Carolina, water year 1992. Water-data report (Annual), 1 October 1991-30 September 1992

    SciTech Connect

    Gunter, H.C.; Rinehardt, J.F.; Eddins, W.H.; Barker, R.G.

    1993-03-31

    Water resources data for the 1992 water year for North Carolina consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and ground-water levels. The report contains discharge records for 163 gaging stations and stage and contents for 56 lakes and reservoirs; water quality for 38 gaging stations and 3 miscellaneous sites; continuous daily tide stage for 16 sites; and water levels for 66 observation wells.

  6. Separation of alcohol-water mixtures by selective adsorption. Semi-annual technical progress report

    SciTech Connect

    Dearborn, R.J.

    1982-03-23

    The intent is to chemically modify polyvinyl chloride so as to convert it to a material capable of selectively adsorbing ethyl alcohol from alcohol-water mixtures. This concept differs from the more conventional technique in which water is absorbed from the mixture by, for example, molecular sieves. The approach is to attempt to remove alcohol from mixtures containing a low percentage of alcohol. Such a solution might originate directly from the fermentation process and contain approximately 10% alcohol, or it might consist of distillation residues containing low alcohol concentrations that are uneconomical to handle by further distillation.

  7. Annual water-resources review, White Sands Missile Range, New Mexico, 1984

    USGS Publications Warehouse

    Cruz, R.R.

    1985-01-01

    Hydrologic data were collected at White Sands Missile Range in 1984. The total groundwater withdrawal in 1984 was 685,275,000 gallons. The Post Headquarters well field produced 650,821,000 gallons in 1984. Six new wells were drilled at White Sands Missile Range in 1984. Nineteen water samples were collected for major chemical-constituent, trace-element, or radiochemical analysis in 1984. Depth-to-water measurements in the Post Headquarters supply wells showed seasonal fluctuations as well as continued long-term declines. (USGS)

  8. Disparate effects of constant and annually-cycling daylength and water temperature on reproductive maturation of striped bass (Morone saxatilis)

    USGS Publications Warehouse

    Clark, R.W.; Henderson-Arzapalo, A.; Sullivan, C.V.

    2005-01-01

    Adult striped bass (Morone saxatilis) were exposed to various combinations of constant or anually-cycling daylength and water temperature. Constant conditions (15 h days, 18??C) were those normally experienced at spawning and cycling conditions simulated natural changes at Chesapeake Bay latitude. Females exposed to constant long (15 h) days and cycling water temperature (TEMPERATURE group) had blood plasma levels of sex steroids (testosterone [T] and estradiol-17?? [E2]) and vitellogenin (Vg), and profiles of oocyte growth, that were nearly identical to those of females held under a natural photothermal cycle (CONTROL group). Several fish from these two groups were induced to spawn fertile eggs. Females constantly exposed to warm water (18??C), with or without a natural photoperiod cycle (PHOTOPERIOD and STATIC groups, respectively), had diminished circulating levels of gonadal steroid hormones and Vg, impaired deposition of yolk granules in their ooplasm, and decreased oocyte growth, and they underwent premature ovarian atresia. Males exposed to cycling water temperature (CONTROL and TEMPERATURE groups) spermiated synchronously during the natural breeding season, at which time they also had had high plasma androgen (T and 11-ketotestosterone [11-KT]) levels. The timing of spermiation was highly asynchronous among males in groups of fish held constantly at 18??C (STATIC and PHOTOPERIOD groups) and this asynchrony was associated with diminished plasma androgen levels. Termination of spermiation by males exposed to cycling water temperature coincided with a sharp decline in levels of plasma androgens about a month after water temperature rose above 18??C. In contrast, most males held constantly at 18??C sustained intermediate levels of plasma androgens and spermiated until the end of the study in late July. The annual cycle of water temperature clearly plays a prominent role in the initiation, maintenance, and termination of the striped bass reproductive cycle. In

  9. Managing Urban Water: Opportunities and Limitations of the Ecosystem Services Framework

    NASA Astrophysics Data System (ADS)

    Hamel, P.; Keeler, B.; Donahue, M.; Hobbie, S. E.; Finlay, J. C.; Brauman, K. A.; Vogl, A.

    2015-12-01

    Traditionally applied to rural environments, the concept of ES is gaining traction in urban areas, overlapping with a number of existing management frameworks in engineering, policy science, political ecology, or urban planning. Given this overlap, it is legitimate to question the value added by the ES concept, either as a theoretical or practical framework. This is particularly the case for urban water management, where new paradigms in engineering and socio-hydrology are increasingly bringing a social dimension to problem solving. In this talk, I will illustrate key opportunities and limitations of the ES framework with a focus on the service of stormwater retention. Drawing from examples in the Global North and South (including Melbourne, Australia, and Cape Town, South Africa), I will show that the ES lens allows: i) an explicit linkage between beneficiaries and grey and green infrastructure, which improves visibility and credibility of techniques valuing urban nature; ii) an improved understanding of tradeoffs and synergies between services, even in regions with limited environmental or socio-economic data; and iii) the development of powerful visualization techniques, enhancing communication with a broad range of stakeholders. These strengths make ES assessments a powerful tool to raise awareness or assist urban planners in realizing their vision of green cities. However, in cities like Melbourne with high capacity and innovative governance, I will argue that the instrumental use of ES is limited and may even be detrimental; limitations of the ES framework, which include a perceived partiality and vagueness, may be used by detractors to undermine the work of urban planners envisioning a greener city. To conclude the talk, I will present the work that the Natural Capital Project is conducting on the application of the ES concept for global indicators of sustainable development, thereby supporting the monitoring and implementation of urban Sustainable

  10. Yield, Quality, Water and Nitrogen Use of Durum and Annual Forages in Two-year Rotations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Available water and nitrogen (N) are typically the biggest constraints to dryland spring durum (Triticum turgidum L. var. durum) production in the northern Great Plains (NGP). A common rotation for spring durum is with summer fallow, which is used to accrue additional soil moisture and N for the su...

  11. Seasonal and annual watershed nitrogen export within the Willamette River Basin (Water in Columia conference)

    EPA Science Inventory

    Anthropogenic nitrogen (N) enrichment is recognized as one of the leading threats to aquatic ecosystems and water quality. In order to manage this threat, we need to understand patterns of N input to the landscape and export from watersheds. Nitrogen export from watersheds is i...

  12. Annual precipitation and effects of runoff-nutrient from agricultural watersheds on water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Declining surface water quality from agricultural nonpoint sources is of great concern across the Platte river basin in Nebraska. Recent changes in the earth climate create abrupt changes in domestic weather (i.e., precipitation, temperature, etc.) which can alter the impact of these nonpoint source...

  13. Water Quality Conditions in the Missouri River Mainstem System: 2006 Annual Report

    DTIC Science & Technology

    2007-07-01

    YANKTON 7.3.1 BACKGROUND INFORMATION 7.3.1.1 Lake Description Lake Yankton is an “ oxbow ” lake of the Missouri River that straddles the Nebraska...19 3.4 Mainstem System Ancillary Lakes – Lake Yankton, Lake Pocasse, and Lake Audubon ............. 19 4 WATER QUALITY ASSESSMENT...95 7 MAINSTEM ANCILLARY LAKES

  14. DYNAMICS OF A SUBTIDAL SEAGRASS LANDSCAPE: SEASONAL AND ANNUAL CHANGE IN RELATION TO WATER DEPTH

    EPA Science Inventory

    The spatial heterogeneity of a subtidal marine landscape and the areal extent of both monospecific and mixed patches of seagrass species were studied in Tampa Bay, FL. Specifically, we examined the temporal dynamics of seagrass distribution and its relationship to water depth an...

  15. The Role of Vegetation Dynamics on the Groundwater Recharge in a Water-Limited Ecosystem

    NASA Astrophysics Data System (ADS)

    Montaldo, N.; Mancini, M.; Albertson, J. D.; Katul, G.

    2003-04-01

    The structure and function of the vegetation regulates the exchange of mass, energy and momentum across the biosphere-atmosphere interface. Root systems affect soil properties, and vegetation density dominates the functioning of hydrological processes through modification of interception, infiltration, evapotranspiration, surface runoff, and groundwater recharge. Influencing the partitioning of incoming solar energy into sensible and latent heat fluxes, the changes in vegetation densities will result in long-term changes in both local and global climates (e.g., precipitation and temperature), and in turn will affect the vegetation growth as a feedback. In semi-arid regions, this may result in persistent drought and desertification, with substantial impacts on the human populations of these regions through reduction in agricultural productivity and reduction in quantity and quality of water supply. In these regions the water becomes a controlling factor, and the groundwater becomes an important water resource. We investigate the role of vegetation dynamics in the soil-vegetation-atmosphere system, and, in particular, on the groundwater recharge in a water-limited ecosystem. The questions addressed are: 1) how does groundwater recharge under grass differ from that under a tree canopy? 2) how does the recharge difference depend on the time scale over which precipitation variability or change occurs? 3) and, to what extent does “temporal change in leaf area” (i.e. denser vegetation in wetter periods) control the answers to the above questions? To reach the objectives, a coupled land surface model (LSM) and vegetation dynamics model is employed. The simple dynamic vegetation model simulates the plant growth, and provides the Leaf Area Index (LAI) evolution through time, which is then used by the LSM in the computation of the energy partitioning between soil and vegetation as well in the parameterization of turbulent transport and evapotranspiration. This updates the

  16. Environmentally assisted cracking in light water reactors annual report January - December 2005.

    SciTech Connect

    Alexandreanu, B.; Chen, Y.; Chopra, O. K.; Chung, H. M.; Gruber, E. E.; Shack, W. J.; Soppet, W. K.

    2007-08-31

    This report summarizes work performed from January to December 2005 by Argonne National Laboratory on fatigue and environmentally assisted cracking in light water reactors (LWRs). Existing statistical models for estimating the fatigue life of carbon and low-alloy steels and austenitic stainless steels (SSs) as a function of material, loading, and environmental conditions were updated. Also, the ASME Code fatigue adjustment factors of 2 on stress and 20 on life were critically reviewed to assess the possible conservatism in the current choice of the margins. An approach, based on an environmental fatigue correction factor, for incorporating the effects of LWR environments into ASME Section III fatigue evaluations is discussed. The susceptibility of austenitic stainless steels and their welds to irradiation-assisted stress corrosion cracking (IASCC) is being evaluated as a function of the fluence level, water chemistry, material chemistry, and fabrication history. For this task, crack growth rate (CGR) tests and slow strain rate tensile (SSRT) tests are being conducted on various austenitic SSs irradiated in the Halden boiling water reactor. The SSRT tests are currently focused on investigating the effects of the grain boundary engineering process on the IASCC of the austenitic SSs. The CGR tests were conducted on Type 316 SSs irradiated to 0.45-3.0 dpa, and on sensitized Type 304 SS and SS weld heat-affected-zone material irradiated to 2.16 dpa. The CGR tests on materials irradiated to 2.16 dpa were followed by a fracture toughness test in a water environment. The effects of material composition, irradiation, and water chemistry on growth rates are discussed. The susceptibility of austenitic SS core internals to IASCC and void swelling is also being evaluated for pressurized water reactors. Both SSRT tests and microstructural examinations are being conducted on specimens irradiated in the BOR-60 reactor in Russia to doses up to 20 dpa. Crack growth rate data

  17. Origins of streamflow in a crystalline basement catchment in a sub-humid Sudanian zone: The Donga basin (Benin, West Africa): Inter-annual variability of water budget

    NASA Astrophysics Data System (ADS)

    Séguis, L.; Kamagaté, B.; Favreau, G.; Descloitres, M.; Seidel, J.-L.; Galle, S.; Peugeot, C.; Gosset, M.; Le Barbé, L.; Malinur, F.; Van Exter, S.; Arjounin, M.; Boubkraoui, S.; Wubda, M.

    2011-05-01

    SummaryDuring the last quarter of the 20th century, West Africa underwent a particularly intense and generalized drought. During this period, the biggest drops in streamflow were observed in the Sudanian zone rather than in the Sahelian zone, but the reasons are still poorly understood. In 2000, a meso-scale hydrological observatory was set up in the sub-humid Sudanian zone of the Upper Ouémé Valley (Benin). Three embedded catchments of 12-586 km 2 located on a crystalline bedrock were intensively instrumented to document the different terms of the water budget and to identify the main streamflow generating processes and base-flow mechanisms at different scales. Geophysical, hydrological and geochemical data were collected throughout the catchments from 2002 to 2006. Crossing these data helped define their hydrological functioning. The region has seasonal streamflow, and the permanent groundwater in the weathered mantle does not drain to rivers, instead, seasonal perched groundwaters are the major contributor to annual streamflow. The perched groundwaters are mainly located in seasonally waterlogged sandy layers in the headwater bottom-lands called bas-fonds in French-speaking West Africa of 1st order streams. During the period 2003-2006, regolith groundwater recharge ranged between 10% and 15% of the annual rainfall depth. Depletion of permanent groundwater during the dry season is probably explained by local evapotranspiration which was seen not to be limited to gallery forests. During the 4-year study period, a reduction of 20% in annual rainfall led to a 50% reduction in streamflow. This reduction was observed in the two components of the flow: direct runoff and drainage of perched groundwater. Thanks to the comprehensive dataset obtained, the results obtained for the Donga experimental catchment are now being extrapolated to the whole upper Ouémé valley, which can be considered as representative of sub-humid Sudanian rivers flowing on a crystalline

  18. Massachusetts Water Resource Research Center: Annual program report, 1988 (FY 1987)

    SciTech Connect

    Not Available

    1988-12-01

    The Massachusetts Water Resources Research Center program for 1987-88 (Federal Fiscal Year FY87) focused on several research areas of high priority for the state and New England region: acid deposition impacts, the minimization of nitrate contamination of groundwater from on-site wastewater treatment, the pricing of drinking water to meet future infrastructure needs, and the proposed diversion of water from a ''Wild and Scenic'' river. Three WRIP Projects were begun in FY87. One evaluates cloud and fog acidity in central Massachusetts, another evaluates the use of peat in rural sewage disposal systems to minimize nitrate contamination of groundwater, and the third will determine the true cost of water so that utilities may appropriately plan for new sources or infrastructure renovation. The Cooperative Aquatic Research Program (CARP) funded five projects; four were acid deposition-related projects. Phase III of the Acid Rain Monitoring Project continued monitoring 500 randomly selected and 300 special interest surface waters quarterly and will continue into its fourth year of the ten year program. Investigation of the role of acid deposition in enhancing microorganisms in lake sediment that may play a role in methylating heavy metals such as mercury continued. Similarly, the study of mechanisms of control of aluminum mobility in watersheds subjected to acid deposition and the study of the impact of acid deposition on salamander communities were continued. Research on the role of sulfate reduction in lakes as a natural mechanism for neutralizing acidity funded in its first year by WRIP, has been continued. All but the Acid Rain Monitoring Project are to be completed in 1988.

  19. Hydrogen production by water dissociation using ceramic membranes. Annual report for FY 2007.

    SciTech Connect

    Balachandran, U.; Chen, L.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Park, C. Y.; Picciolo, J. J.; Song, S. J.; Energy Systems

    2008-03-04

    The objective of this project is to develop dense ceramic membranes that, without using an external power supply or circuitry, can produce hydrogen via coal/coal gas-assisted water dissociation. This project grew out of an effort to develop a dense ceramic membrane for separating hydrogen from gas mixtures such as those generated during coal gasification, methane partial oxidation, and water-gas shift reactions [1]. That effort led to the development of various cermet (i.e., ceramic/metal composite) membranes that enable hydrogen to be produced by two methods. In one method, a hydrogen transport membrane (HTM) selectively removes hydrogen from a gas mixture by transporting it through either a mixed protonic/electronic conductor or a hydrogen transport metal. In the other method, an oxygen transport membrane (OTM) generates hydrogen mixed with steam by removing oxygen that is generated through water splitting [1, 2]. This project focuses on the development of OTMs that efficiently produce hydrogen via the dissociation of water. Supercritical boilers offer very high-pressure steam that can be decomposed to provide pure hydrogen by means of OTMs. Oxygen resulting from the dissociation of steam can be used for coal gasification, enriched combustion, or synthesis gas production. Hydrogen and sequestration-ready CO{sub 2} can be produced from coal and steam by using the membrane being developed in this project. Although hydrogen can also be generated by high-temperature steam electrolysis, producing hydrogen by water splitting with a mixed-conducting membrane requires no electric power or electrical circuitry.

  20. Environmentally assisted cracking in light water reactors - annual report, January-December 2001.

    SciTech Connect

    Chopra, O. K.; Chung, H. M.; Clark, R. W.; Gruber, E. E; Hiller, R. W.; Shack, W. J.; Soppet, W. K.; Strain, R. V.; Energy Technology

    2003-06-01

    This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors (LWRs) from January to December 2001. Topics that have been investigated include (a) environmental effects on fatigue S-N behavior of austenitic stainless steels (SSs), (b) irradiation-assisted stress corrosion cracking (IASCC) of austenitic SSs, and (c) EAC of Alloy 600. The effects of key material and loading variables, such as strain amplitude, strain rate, temperature, dissolved oxygen (DO) level in water, and material heat treatment, on the fatigue lives of wrought and cast austenitic SSs in air and LWR environments have been evaluated. The mechanism of fatigue crack initiation in austenitic SSs in LWR environments has also been examined. The results indicate that the presence of a surface oxide film or difference in the characteristics of the oxide film has no effect on fatigue crack initiation in austenitic SSs in LWR environments. Slow-strain-rate tensile tests and post-test fractographic analyses were conducted on several model SS alloys irradiated to {approx}2 x 10{sup 21} n {center_dot} cm{sup -2} (E > 1 MeV) ({approx}3 dpa) in He at 289 C in the Halden reactor. The results were used to determine the influence of alloying and impurity elements on the susceptibility of these steels to IASCC. Corrosion fatigue tests were conducted on nonirradiated austenitic SSs in high-purity water at 289 C to establish the test procedure and conditions that will be used for the tests on irradiated materials. A comprehensive irradiation experiment was initiated to obtain many tensile and disk specimens irradiated under simulated pressurized water reactor conditions at {approx}325 C to 5, 10, 20, and 40 dpa. Crack growth tests were completed on 30% cold-worked Alloy 600 in high-purity water under various environmental and loading conditions. The results are compared with data obtained earlier on several heats of Alloy 600

  1. Contribution of maternal radionuclide burdens to prenatal radiation doses: Relationships between annual limits on intake and prenatal doses. Revision 1, Addendum 1

    SciTech Connect

    Sikov, M.R.; Hui, T.E.

    1993-10-01

    This addendum describes approaches for calculating and expressing radiation doses to the embryo/fetus from maternal intakes of radionuclides at levels corresponding to fractions or multiples of the Annual Limits on Intake (ALI). Information, concerning metabolic or dosimetric characteristics and the placental transfer of selected, occupationally significant radionuclides was presented in NUREG/CR-5631, Revision 1. That information was used to estimate levels of radioactivity in the embryo/fetus as a function of stage of pregnancy and time after entry. Extension of MIRD methodology to accommodate gestational-stage-dependent characteristics allowed dose calculations for the simplified situation based on introduction of 1 {mu}Ci into the woman`s transfer compartment (blood). The expanded scenarios in this addendum include repeated or chronic ingestion or inhalation intakes by a woman during pregnancy and body burdens at the beginning of pregnancy. Tables present dose equivalent to the embryo/fetus relative to intakes of these radionuclides in various chemical or physical forms and from preexisting maternal burdens corresponding to ALI; complementary intake values (fraction of an ALI and {mu}Ci) that yield a dose equivalent of 0.05 rem are included. Similar tables give these measures of dose equivalency to the uterus from intakes of radionuclides for use as surrogates for embryo/fetus dose when biokinetic information is not available.

  2. Water Budget Managers Report to Northwest Power Planning Council, 1984 Annual Report.

    SciTech Connect

    Water Budget Managers

    1984-11-01

    The report contains a summary of the 1984 flow conditions, Water Budget management, and flow shaping to meet the needs of the smolt outmigration. In addition, a summary of activities conducted under the Smolt Monitoring Program is provided, as is preliminary data on the timing and duration of the smolt outmigration as required by Section 304(C)(3)(B). 6 refs., 14 figs., 7 tabs.

  3. Fresh-water lenses and practical limitations of their three-dimensional simulation

    NASA Astrophysics Data System (ADS)

    Ghassemi, F.; Alam, K.; Howard, K. W. F.

    2000-10-01

    Fresh-water lenses are the major sources of water supply in many atoll islands in the Pacific and Indian Oceans, particularly in dry seasons. Several two- and three-dimensional models are currently available for the simulation of atoll-island aquifers; however, 2D models cannot include 3D spatial variability of material properties, they must simplify the boundary conditions, and they cannot correctly simulate pumping wells. In an attempt to overcome these difficulties, a 3D model, SALTFLOW, was adopted for the simulation of Home Island in the Indian Ocean. This exercise required a discretisation on the order of a few metres and time steps of a few hours requiring significantly high CPU times. High CPU demand proved to be a difficult challenge but cannot be considered a serious practical limitation with today's advanced computers. The exhaustive data demands of the model (e.g., 3D distributions of hydraulic conductivity, porosity, dispersivities, and spatial and temporal variations of recharge and extraction rates) proved to be more problematical. Although the Home Island data set is unusually comprehensive by any standards, nonetheless the quality and quantity of the available data proved inadequate to meet the calibration needs of a highly karstic aquifer system. The Home Island modeling demonstrates the practical limitations of 3D models. It raises the concern that our ability to develop computer codes capable of simulating complex systems now exceeds our ability to supply the input data necessary for reliable calibration. Finally, the paper demonstrates the importance of the transient calibration in reliable simulation of various management options and emphasises that transient calibration should be considered as an integral part of any similar 2D or 3D modeling.

  4. Early life history of deep-water gorgonian corals may limit their abundance.

    PubMed

    Lacharité, Myriam; Metaxas, Anna

    2013-01-01

    Deep-water gorgonian corals are long-lived organisms found worldwide off continental margins and seamounts, usually occurring at depths of ∼200-1,000 m. Most corals undergo sexual reproduction by releasing a planktonic larval stage that disperses; however, recruitment rates and the environmental and biological factors influencing recruitment in deep-sea species are poorly known. Here, we present results from a 4-year field experiment conducted in the Gulf of Maine (northwest Atlantic) at depths >650 m that document recruitment for 2 species of deep-water gorgonian corals, Primnoa resedaeformis and Paragorgia arborea. The abundance of P. resedaeformis recruits was high, and influenced by the structural complexity of the recipient habitat, but very few recruits of P. arborea were found. We suggest that divergent reproductive modes (P. resedaeformis as a broadcast spawner and P. arborea as a brooder) may explain this pattern. Despite the high recruitment of P. resedaeformis, severe mortality early on in the benthic stage of this species may limit the abundance of adult colonies. Most recruits of this species (∼80%) were at the primary polyp stage, and less than 1% of recruits were at stage of 4 polyps or more. We propose that biological disturbance, possibly by the presence of suspension-feeding brittle stars, and limited food supply in the deep sea may cause this mortality. Our findings reinforce the vulnerability of these corals to anthropogenic disturbances, such as trawling with mobile gear, and the importance of incorporating knowledge on processes during the early life history stages in conservation decisions.

  5. Early Life History of Deep-Water Gorgonian Corals May Limit Their Abundance

    PubMed Central

    Lacharité, Myriam; Metaxas, Anna

    2013-01-01

    Deep-water gorgonian corals are long-lived organisms found worldwide off continental margins and seamounts, usually occurring at depths of ∼200–1,000 m. Most corals undergo sexual reproduction by releasing a planktonic larval stage that disperses; however, recruitment rates and the environmental and biological factors influencing recruitment in deep-sea species are poorly known. Here, we present results from a 4-year field experiment conducted in the Gulf of Maine (northwest Atlantic) at depths >650 m that document recruitment for 2 species of deep-water gorgonian corals, Primnoa resedaeformis and Paragorgia arborea. The abundance of P. resedaeformis recruits was high, and influenced by the structural complexity of the recipient habitat, but very few recruits of P. arborea were found. We suggest that divergent reproductive modes (P. resedaeformis as a broadcast spawner and P. arborea as a brooder) may explain this pattern. Despite the high recruitment of P. resedaeformis, severe mortality early on in the benthic stage of this species may limit the abundance of adult colonies. Most recruits of this species (∼80%) were at the primary polyp stage, and less than 1% of recruits were at stage of 4 polyps or more. We propose that biological disturbance, possibly by the presence of suspension-feeding brittle stars, and limited food supply in the deep sea may cause this mortality. Our findings reinforce the vulnerability of these corals to anthropogenic disturbances, such as trawling with mobile gear, and the importance of incorporating knowledge on processes during the early life history stages in conservation decisions. PMID:23762358

  6. Modeling Interfacial Glass-Water Reactions: Recent Advances and Current Limitations

    SciTech Connect

    Pierce, Eric M.; Frugier, Pierre; Criscenti, Louise J.; Kwon, Kideok D.; Kerisit, Sebastien N.

    2014-07-12

    Describing the reactions that occur at the glass-water interface and control the development of the altered layer constitutes one of the main scientific challenges impeding existing models from providing accurate radionuclide release estimates. Radionuclide release estimates are a critical component of the safety basis for geologic repositories. The altered layer (i.e., amorphous hydrated surface layer and crystalline reaction products) represents a complex region, both physically and chemically, sandwiched between two distinct boundaries pristine glass surface at the inner most interface and aqueous solution at the outer most interface. Computational models, spanning different length and time-scales, are currently being developed to improve our understanding of this complex and dynamic process with the goal of accurately describing the pore-scale changes that occur as the system evolves. These modeling approaches include geochemical simulations [i.e., classical reaction path simulations and glass reactivity in allowance for alteration layer (GRAAL) simulations], Monte Carlo simulations, and Molecular Dynamics methods. Finally, in this manuscript, we discuss the advances and limitations of each modeling approach placed in the context of the glass-water reaction and how collectively these approaches provide insights into the mechanisms that control the formation and evolution of altered layers.

  7. Modeling Interfacial Glass-Water Reactions: Recent Advances and Current Limitations

    SciTech Connect

    Pierce, Eric M.; Frugier, Pierre; Criscenti, Louise J.; Kwon, K. D.; Kerisit, Sebastien N.

    2014-07-12

    The altered layer (i.e., amorphous hydrated surface layer and crystalline reaction products)represents a complex region, both physically and chemically, sandwiched between two distinct boundaries - pristine glass surface at the inner most interface and aqueous solution at the outer most. The physico-chemical processes that control the development of this region have a significant impact on the long-term glass-water reaction. Computational models, spanning different length and time-scales, are currently being developed to improve our understanding of this complex and dynamic process with the goal of accurately describing the pore-scale changes that occur as the system evolves. These modeling approaches include Geochemical Reaction Path simulations, Glass Reactivity in Allowance for Alteration Layer simulations, Monte Carlo simulations, and Molecular Dynamics methods. Discussed in this manuscript are the advances and limitations of each modeling approach placed in the context of the glass water reaction and how collectively these approaches provide insights into the mechanisms that control the formation and evolution of altered layers; thus providing the fundamental data needed to develop pore-scale equations that enable more accurate predictions of nuclear waste glass corrosion in a geologic repository.

  8. Modeling Interfacial Glass-Water Reactions: Recent Advances and Current Limitations

    DOE PAGES

    Pierce, Eric M.; Frugier, Pierre; Criscenti, Louise J.; ...

    2014-07-12

    Describing the reactions that occur at the glass-water interface and control the development of the altered layer constitutes one of the main scientific challenges impeding existing models from providing accurate radionuclide release estimates. Radionuclide release estimates are a critical component of the safety basis for geologic repositories. The altered layer (i.e., amorphous hydrated surface layer and crystalline reaction products) represents a complex region, both physically and chemically, sandwiched between two distinct boundaries pristine glass surface at the inner most interface and aqueous solution at the outer most interface. Computational models, spanning different length and time-scales, are currently being developed tomore » improve our understanding of this complex and dynamic process with the goal of accurately describing the pore-scale changes that occur as the system evolves. These modeling approaches include geochemical simulations [i.e., classical reaction path simulations and glass reactivity in allowance for alteration layer (GRAAL) simulations], Monte Carlo simulations, and Molecular Dynamics methods. Finally, in this manuscript, we discuss the advances and limitations of each modeling approach placed in the context of the glass-water reaction and how collectively these approaches provide insights into the mechanisms that control the formation and evolution of altered layers.« less

  9. Limitation of fluorescence spectrophotometry in the measurement of naphthenic acids in oil sands process water.

    PubMed

    Lu, Weibing; Ewanchuk, Andrea; Perez-Estrada, Leonidas; Sego, Dave; Ulrich, Ania

    2013-01-01

    Fluorescence spectrophotometry has been proposed as a quick screening technique for the measurement of naphthenic acids (NAs). To evaluate the feasibility of this application, the fluorescence emission spectra of NAs extracted from three oil sands process water sources were compared with that of commercial NAs. The NAs resulting from the bitumen extraction process cannot be differentiated because of the similarity of the fluorescence spectra. Separation of the fluorescent species in NAs using high performance liquid chromatography with fluorescence detector proved unsuccessful. The acidic fraction of NAs is fluorescent but the basic fraction of NAs is not fluorescent, implying that aromatic acids in NAs give rise to the fluorescent signals. The concentrations of NAs in oil sands process water were measured by Fourier transform infrared spectroscopy (FTIR), fluorescence spectrophotometry and ultra high performance liquid chromatography-time of flight/mass spectrometry (UPLC-TOF/MS). Commercial Merichem and Kodak NAs are the best standards to use when measuring NAs concentration with FTIR and fluorescence spectrophotometry. In addition, the NAs concentrations measured by fluorescence spectrophotometry are about 30 times higher than those measured by FTIR and UPLC-TOF/MS. The findings in this study underscore the limitation of fluorescence spectrophotometry in the measurement of NAs.

  10. High-resolution imaging and spectroscopy of interfacial water at single bond limit

    NASA Astrophysics Data System (ADS)

    Jiang, Ying

    Hydrogen bond is one of the most important weak interactions in nature and plays an essential role in a broad spectrum of physics, chemistry, biology, energy and material sciences. The conventional methods for studying hydrogen-bonding interaction are all based on spectroscopic or diffraction techniques. However, those techniques have poor spatial resolution and only measure the average properties of many hydrogen bonds, which are susceptible to the structural inhomogeneity and local environments, especially when interfacial systems are concerned. The spatial variation and inter-bond coupling of the hydrogen bonds leads to significant spectral broadening, which prohibits the accurate understanding of the experimental data. In this talk, I will present our recent progress on the development of new-generation scanning probe microscopy/spectroscopy (SPM/S) with unprecedentedly high sensitivity and resolution, for addressing weak inter- and intra-molecular interactions, such as hydrogen bonds and van der Waals force. Based on a qPlus sensor, we have succeeded to push the real-space study of a prototypical hydrogen-bonded system, i.e. water, down to single bond limit. Combined with state-of-the-arts quantum simulations, we have discovered exotic nuclear quantum effects (NQEs) in interfacial water and revealed the quantum nature of the hydrogen bond from a completely new perspective

  11. Approaching the ppb detection limits for copper in water using laser induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Tawfik, Walid; Sawaf, Sausan

    2014-05-01

    Copper concentrations in drinking-water is very important to be monitored which can cause cancer if it exceed about 10 mg/liter. In the present work, we have developed a simple, low laser power method to improve the detection limits of laser induced plasma spectroscopy LIBS for copper in aqueous solutions with different concentrations. In this method a medium density fiberboard (MDF) wood have been used as a substrate that absorbs the liquid sample to transform laser liquid interaction to laser solid interaction. Using the fundamental wavelength of Nd:YAG laser, the constructed plasma emissions were monitored for elemental analysis. The signal-to-noise ratio SNR was optimized using low laser fluence of 32 J cm-2, and detector (CDD camera) gate delay of 0.5 μs. Both the electron temperature and density of the induced plasma were determined using Boltzmann plot and the FWHM of the Cu at 324.7 nm, respectively. The plasma temperature was found to be 1.197 eV, while the plasma density was about 1.66 x 1019 cm-3. The detection limits for Cu at 324.7 nm is found to be 131 ppb comparable to the results by others using complicated system.

  12. Thermal-hydraulic limitations on water-cooled fusion reactor components

    SciTech Connect

    Cha, Y.S.; Misra, B.

    1986-01-01

    An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on conventional design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require unconventional shapes or heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under asymmetrically heated conditions. Since the data presented herein are concerned primarily with thermal protection of the reactor components, the final design should consider other factors such as thermal stresses, temperature limits, and fatigue.

  13. Transcriptome Profiling of Wild Arachis from Water-Limited Environments Uncovers Drought Tolerance Candidate Genes.

    PubMed

    Brasileiro, Ana C M; Morgante, Carolina V; Araujo, Ana C G; Leal-Bertioli, Soraya C M; Silva, Amanda K; Martins, Andressa C Q; Vinson, Christina C; Santos, Candice M R; Bonfim, Orzenil; Togawa, Roberto C; Saraiva, Mario A P; Bertioli, David J; Guimaraes, Patricia M

    Peanut (Arachis hypogaea L.) is an important legume cultivated mostly in drought-prone areas where its productivity can be limited by water scarcity. The development of more drought-tolerant varieties is, therefore, a priority for peanut breeding programs worldwide. In contrast to cultivated peanut, wild relatives have a broader genetic diversity and constitute a rich source of resistance/tolerance alleles to biotic and abiotic stresses. The present study takes advantage of this diversity to identify drought-responsive genes by analyzing the expression profile of two wild species, Arachis duranensis and Arachis magna (AA and BB genomes, respectively), in response to progressive water deficit in soil. Data analysis from leaves and roots of A. duranensis (454 sequencing) and A. magna (suppression subtractive hybridization (SSH)) stressed and control complementary DNA (cDNA) libraries revealed several differentially expressed genes in silico, and 44 of them were selected for further validation by quantitative RT-PCR (qRT-PCR). This allowed the identification of drought-responsive candidate genes, such as Expansin, Nitrilase, NAC, and bZIP transcription factors, displaying significant levels of differential expression during stress imposition in both species. This is the first report on identification of differentially expressed genes under drought stress and recovery in wild Arachis species. The generated transcriptome data, besides being a valuable resource for gene discovery, will allow the characterization of new alleles and development of molecular markers associated with drought responses in peanut. These together constitute important tools for the peanut breeding program and also contribute to a better comprehension of gene modulation in response to water deficit and rehydration.

  14. Cultivar Mixture Cropping Increased Water Use Efficiency in Winter Wheat under Limited Irrigation Conditions

    PubMed Central

    Wang, Yunqi; Zhang, Yinghua; Ji, Wei; Yu, Peng; Wang, Bin; Li, Jinpeng; Han, Meikun; Xu, Xuexin; Wang, Zhimin

    2016-01-01

    The effects of cultivar mixture cropping on yield, biomass, and water use efficiency (WUE) in winter wheat (Triticum aestivum L.) were investigated under non-irrigation (W0, no irrigation during growth stage), one time irrigation (W1, irrigation applied at stem elongation) and two times irrigation (W2, irrigation applied at stem elongation and anthesis) conditions. Nearly 90% of cultivar mixture cropping treatments experienced an increase in grain yield as compared with the mean of the pure stands under W0, those for W1 and W2 were 80% and 85%, respectively. Over 75% of cultivar mixture cropping treatments got greater biomass than the mean of the pure stands under the three irrigation conditions. Cultivar mixture cropping cost more water than pure stands under W0 and W1, whereas the water consumption under W2 decreased by 5.9%–6.8% as compared with pure stands. Approximately 90% of cultivar mixtures showed an increase of 5.4%–34.5% in WUE as compared with the mean of the pure stands, and about 75% of cultivar mixtures had 0.8%–28.5% higher WUE than the better pure stands under W0. Similarly, there were a majority of mixture cropping treatments with higher WUE than the mean and the better one of the pure stands under W1 and W2. On the whole, proper cultivar mixture cropping could increase yield and WUE, and a higher increase in WUE occurred under limited irrigation condition. PMID:27362563

  15. Sea-water magnetohydrodynamic propulsion for next-generation undersea vehicles. Annual report, 1 February 1989-31 January 1990

    SciTech Connect

    Lin, T.F.; Gilbert, J.B.; Kossowsky, R.

    1990-02-01

    Three tasks were performed in this report period. Their individual abstracts are summarized as follows: (I) Thruster Performance Modelings - The purpose of this work is to analyze underwater vehicle propulsion by applying Lorentz forces to the surrounding sea water. While this propulsion concept involves two different schemes, i.e. the external field method and the internal duct-type method, the current analysis focuses on the internal thruster scheme due to the space limitations and speed considerations. The theories of magnetohydrodynamic (MHD) pump jet propulsion are discussed. A so-called dual control volume analysis to model the MHD thruster, and calculations of vehicle velocity and power efficiency are presented. (II) Sea Water Conductivity Enhancement - This work discusses the mechanisms of enhancing the electric conductivity of sea water. The direct impact of conductivity enhancement of sea water is the improvement of propulsion performances of marine vehicles that use the magnetohydrodynamic thrusts of sea water. The performance improvement can be in energy efficiency or in vehicle speed. Injection of strong electrolytes (acids or bases) into the main sea water flow in the MHD channel appeared to be the most logical way of achieving the purpose. (III) Status of Current Superconductivity Works - A survey of recent research in both low -T{sub c} and high -T{sub c} superconductivities is provided. It is generally true that high -T{sub c} superconductors carry critical current densities several orders of magnitude less than those of low -T{sub c} ones.

  16. Characteristics of biofilm community formed in the chlorinated biodegradable organic matter-limited tap water.

    PubMed

    Park, S K; Lee, S H; Choi, S C; Kim, Y K

    2006-04-01

    The aim of this study was to characterize the influence of free chlorine residual on biofilm formation in a chlorinated system in which the biodegradable organic matter (BOM) was limited. The biofilm community was characterized through a community-level physiological profile (CLPP) that was generated using the Biolog GN microplate-based community-level assay. The chlorinated system was run at chlorine residual concentrations of 0.3, 0.5, and 1.0 mg l(-1) with the provision of BOM-limited tap water (0.01 mg l(-1) as assimilable organic carbon and 0.06 mg l(-1) as biodegradable dissolved organic carbon). For comparison, an unchlorinated system was operated in parallel under the same condition. The number of viable heterotrophic bacteria in the biofilm that formed in the chlorinated system over the 3 months of operation averaged 7.2 x 10(3), 4.8 x 10, and 1.6 x 10 CFU cm(-2) for the chlorine residual concentrations of 0.3, 0.5, and 1.0 mg l(-1), respectively. In the unchlorinated system, the average bacterial content was 1.1 x 10(6) CFU cm(-2). Using measures of substrate utilization rate, substrate utilization diversity, and metabolic potential index (MPI), the CLPP patterns demonstrated that the metabolic potentials of the biofilm communities decreased markedly as the chlorine residual levels increased. In particular, the community level of the biofilm that formed in the system with chlorine residual concentration of 1.0 mg l(-1) was the lowest of any biofilm under the tested conditions. The results implied that chlorine residual had a positive biocidal effect on the metabolic potential and/or functional potential of the biofilm community, especially when the BOM level was low. In addition, BOM limitation by itself was not sufficient to control biofilm formation.

  17. Strategies for maintaining fruit quality in northern highbush blueberry under water limited conditions: Deficit irrigation and reduced crop loads

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many commercial blueberry (Vaccinium sp.) fields are irrigated, but mandatory water restrictions may soon limit the availability of irrigation water in several important blueberry growing regions such as California and eastern Washington. New strategies are needed to maintain fruit quality with less...

  18. Nuclear magnetic resonance imaging of subsurface water content. 1997 annual progress report

    SciTech Connect

    Hendrickx, J.M.H.

    1997-01-01

    'During the period from October 1997 to January 1998 the author has further developed the understanding of NMR physics, improved software for forward and inverse modeling of the NMR signal, and conducted field tests on sites in Colorado and New Mexico. One important result from the forward modeling was that the field strength of the signals is concentrated under the loop. This indicates that little lateral dissipation occurs. The author received the NUMIS/NMR system (manufactured by IRIS Instruments, France) in late July, 1997. In July and early August, 1997, potential test sites were visited, and several test sites were selected and permitted. The first NMR test measurements were made in mid-August, 1997. The instrument malfunctioned during mid-September, 1997, and was returned to IRIS for repairs. Time lost due to malfunction, repairs, and shipping was about one month. Many NMR measurements have been made at sites in Colorado and New Mexico. Parks often have been selected as test sites due to ease of permitting, the relatively large open space, and general lack of powerlines. Noise from power lines severely degrades the NMR data quality. The NMR data acquired at the first three sites in Colorado (Bear Creek, Clear Creek, and Prospect) was either severely distorted by powerline noise or did not indicate significant groundwater occurrences. The NMR data taken at Cherry Creek were of good quality and also indicated significant groundwater. The NMR data acquired at three sites with relatively shallow ground water levels around Socorro, New Mexico, did not detect any ground water due to severe signal distortion by magnetite, a magnetic mineral. Measurements in a compact sand stone near Santa Rosa and in a limestone near Artesia, New Mexico, gave excellent results. Overall, the NMR technique proves capable of detecting subsurface ground water under the right conditions: little noise from power lines and absence of magnetite.'

  19. Fundamental studies of water pretreatment of coal. Second annual report, October 1, 1990--September 30, 1991

    SciTech Connect

    Serio, M.A.; Kroo, E.; Solomon, P.R.; Charpenay, S.; Bassilakis, R.

    1991-12-31

    The goals of this project are to gain an understanding of the chemistry of water or steam coal pretreatments and to assess the importance of such pretreatments on subsequent coal liquefaction. For the achievement of these goals, coals, modified coals and model-polymers will be treated with water or steam. This study will include three coals, five modifications (dried, demineralized, ion-exchanged, Ca-loaded, Ba-loaded), three polymers and two polymer modifications (e.g., acid chlorides, amides). Experiments will be performed to investigate both conventional steam pretreatment and the possibility of using the CO/H{sub 2}O system of Ross and coworkers as a pretreatment method. The main experimental variables will be sample type and temperature. Detailed characterization of the gas, liquid and solid products from the pretreatment stage will be done. This will include analysis of gases by GC or FT-IR, liquids by capillary GC, FT-IR and FIMS, and residues by solvent swelling, solvent extraction, and elemental analysis. Selected residues will also be evaluated by a standard liquefaction test. Analysis of the raw coals and pretreatment samples will be performed using the above techniques to study changes in the crosslinking, donatable hydrogen, heteroatom composition, evolved gases, functional group composition, extraction yields, molecular weight distributions, etc. Standard tubing bomb liquefaction tests will be used to determine the effect of pretreatment on coal reactivity toward coal liquefaction. A previously developed model for coal liquefaction, the FG-DVC liquefaction model, will be used (after appropriate modifications) to model the physics and chemistry of water pretreatment.

  20. Comprehensive cooling water study annual report. Volume IX: waterfowl, Savannah River Plant

    SciTech Connect

    Gladden, J.B.; Lower, M.W.; Mackey, H.E.; Specht, W.L.; Wilde, E.W.

    1985-07-01

    The Savannah River Swamp System (SRSS) and Par Pond are used extensively by waterfowl, particularly during the fall and winter months when these areas provide habitat for migratory species. Twelve species of waterfowl are known to inhabit the SSRS, eleven are migratory species, and the wood duck is a year-round resident. Mallard ducks use the Four Mile Creek delta area of the SRSS during the winter if water levels are low, but use the Steel Creek delta if water levels are high during flooding from the Savannah River. Use of the thermal areas in Four Mile Creek and Pen Branch by waterfowl has been observed to decline in late February, while use of the Steel Creek swamp and Beaver Dam Creek area increases from March to May. Wood ducks appear to be dependent upon persistent and nonpersistent marsh and bottomland hardwood plant communities of the SRSS for foraging, but roost in scrub-shrub communities. The marsh and scrub-shrub communities are enhanced in the post-thermal Steel Creek delta relative to the river swamp areas, which explains the apparent importance of the Steel Creek delta area for these waterfowl. Portions of the Steel Creek delta which were previously excellent nesting habitat for wood ducks are providing poorer nesting habitat due to vegetational succession which has taken place since thermal discharges from L Reactor ended in 1968. Increased flow in the Steel Creek delta which would result from the restart of L Reactor may adversely affect waterfowl roosting and feed areas by increasing water depth and velocity and by altering vegetational patterns. 11 refs., 18 figs., 5 tabs.

  1. Lake Roosevelt Fisheries Evaluation Program; Evaluation of Limiting Factors for Stocked Kokanee and Rainbow Trout in Lake Roosevelt, Washington, 1999 Annual Report.

    SciTech Connect

    Baldwin, Casey; Polacek, Matt

    2009-03-01

    Hatchery supplementation of kokanee Oncorhynchus nerka and rainbow trout O. mykiss has been the primary mitigation provided by Bonneville Power Administration for loss of anadromous fish to the waters above Grand Coulee Dam (GCD). The hatchery program for rainbow trout has consistently met management goals and provided a substantial contribution to the fishery; however, spawner returns and creel survey results for kokanee have been below management goals. Our objective was to identify factors that limit limnetic fish production in Lake Roosevelt by evaluating abiotic conditions, food limitations, piscivory, and entrainment. Dissolved oxygen concentration was adequate throughout most of the year; however, levels dropped to near 6 mg/L in late July. For kokanee, warm water temperatures during mid-late summer limited their nocturnal distribution to 80-100 m in the lower section of the reservoir. Kokanee spawner length was consistently several centimeters longer than in other Pacific Northwest systems, and the relative weights of rainbow trout and large kokanee were comparable to national averages. Large bodied daphnia (> 1.7 mm) were present in the zooplankton community during all seasons indicating that top down effects were not limiting secondary productivity. Walleye Stizostedion vitreum were the primary piscivore of salmonids in 1998 and 1999. Burbot Lota lota smallmouth bass Micropterus dolomieui, and northern pikeminnow Ptychocheilus oregonensis preyed on salmonids to a lesser degree. Age 3 and 4 walleye were responsible for the majority (65%) of the total walleye consumption of salmonids. Bioenergetics modeling indicated that reservoir wide consumption by walleye could account for a 31-39% loss of stocked kokanee but only 6-12% of rainbow trout. Size at release was the primary reason for differential mortality rates due to predation. Entrainment ranged from 2% to 16% of the monthly abundance estimates of limnetic fish, and could account for 30% of total

  2. Recommendations for fluoride limits in drinking water based on estimated daily fluoride intake in the Upper East Region, Ghana.

    PubMed

    Craig, Laura; Lutz, Alexandra; Berry, Kate A; Yang, Wei

    2015-11-01

    Both dental and skeletal fluorosis caused by high fluoride intake are serious public health concerns around the world. Fluorosis is particularly pronounced in developing countries where elevated concentrations of naturally occurring fluoride are present in the drinking water, which is the primary route of exposure. The World Health Organization recommended limit of fluoride in drinking water is 1.5 mg F(-) L(-1), which is also the upper limit for fluoride in drinking water for several other countries such as Canada, China, India, Australia, and the European Union. In the United States the enforceable limit is much higher at 4 mg F(-) L(-1), which is intended to prevent severe skeletal fluorosis but does not protect against dental fluorosis. Many countries, including the United States, also have notably lower unenforced recommended limits to protect against dental fluorosis. One consideration in determining the optimum fluoride concentration in drinking water is daily water intake, which can be high in hot climates such as in northern Ghana. The results of this study show that average water intake is about two times higher in Ghana than in more temperate climates and, as a result, the fluoride intake is higher. The results also indicate that to protect the Ghanaian population against dental fluorosis, the maximum concentration of fluoride in drinking water for children under 6-8 years should be 0.6 mg F(-) L(-1) (and lower in the first two years of life), and the limit for older children and adults should be 1.0 mg F(-) L(-1). However, when considering that water treatment is not cost-free, the most widely recommended limit of 1.5 mg F(-) L(-1) - which is currently the limit in Ghana--may be appropriate for older children and adults since they are not vulnerable to dental fluorosis once the tooth enamel is formed.

  3. Photosynthetic water splitting. Annual report, November 1, 1981-October 31, 1982

    SciTech Connect

    Greenbaum, E.

    1982-12-01

    The first measurements of the simultaneous photoproduction of hydrogen and oxygen in marine green algae have been performed. Eight species in the general Chlamydomonas, Chlorella, and Halochlorocococcum were tested in CO/sub 2/-free sea water. Four of the five species of Chlamydomonas were able to produce hydrogen in the light after a period of 3 to 4 h of dark anaerobic adaptation. Only one of the two Chlorella species tested was able to photoproduce hydrogen - in trace amounts. Halochlorocococcum fla-9 gave positive results, and Chlamydomonas species (clone f-9) had a steady-state rate of hydrogen and oxygen production during irradiation with a stoichiometric ratio near 2:1. The integrated yields of hydrogen and oxygen produced by this species correspond to about 450 turnovers of the photochemical reaction centers. This number exceeds (by about a factor of 20) the electron-carrying capacity of the electron transport chain linking Photosystems I and II. These data suggest that Chlamydomonas f-9 makes sea water a potential substrate for solar hydrogen and oxygen production.

  4. Effect of pinealectomy on annual testicular cycle of Indian chequered water snake, Natrix piscator.

    PubMed

    Haldar, C; Pandey, R

    1989-11-01

    Pinealectomy for 60 days (noted every month of the year), in the tropical Indian chequered water snake. Natrix piscator, caused inhibition of testicular growth during late progressive and active phases and retarded the rate of regression during regressive phase; during sexually inactive phase the testes remain partially active. The weight of the accessory sex organs, vas deferens, and kidney (along with the renal sex segment activity) followed the same pattern as that of the testes. Thus, it may be concluded that the pineal gland of this ophidian participates in the regulation of seasonal testicular cycle, probably via the hypothalamo-hypophyseal axis, and hence the effects of pinealectomy are seasonal and a reproductive phase-dependent phenomenon.

  5. Environmental impacts on the evapotranspiration of an water limited and heterogeneous Mediterranean ecosystem.

    NASA Astrophysics Data System (ADS)

    Montaldo, N.; Curreli, M.; Corona, R.; Oren, R.

    2015-12-01

    Mediterranean water limited ecosystems are characterized by an heterogeneous spatial distribution of different plant functional types (PFT), such as grass and trees, competing for water use. Typically, during the dry summers, these ecosystems are characterized by a simple dual PFTs system with strong-resistant woody vegetation and bare soil, since grass died. The coupled use of sap flow measurements and eddy covariance technique is essential to estimate Evapotransiration (ET) in an heterogeneous ecosystem. An eddy covariance - micrometeorological tower has been installed since 2003 and 33 thermo-dissipation probes based on the Granier technique have installed at the Orroli site in Sardinia (Italy). The site landscape is a mixture of Mediterranean patchy vegetation types: wild olives, different shrubs and herbaceous species, which died during the summer. The sensors have been installed at the Orroli site into 15 wild olives clumps with different characteristics in terms of tree size, exposition to wind and solar radiation and soil depth. A network of 30 soil moisture sensors has also been installed for monitoring soil moisture spatial and temporal dynamics and their correlation with trees. Sap flow measurements show the significantly impacts on ET of soil moisture, radiation, vapor pressure deficit (VPD) and interestingly of tree position into the clump, showing double rates for the trees inside the wild olive clumps. The sap flow sensor outputs are analyzed for estimating innovative allometric relationships between sapwood area, diameter, canopy cover area, which are needed for the correct upscale of the local tree measurements to the site plot larger scale. Finally using an innovative scaling procedure, the sap-flow transpiration at field scale have been compared to the eddy covariance ET, showing the approximation of the eddy covariance technique. Finally the impact of environmental factors on ET for different soil depth and tree position is demonstrated.

  6. Environmental impacts on the evapotranspiration of an water limited and heterogeneous Mediterranean ecosystem.

    NASA Astrophysics Data System (ADS)

    Mackay, D. S.; Ewers, B. E.; Sperry, J. S.; Frank, J. M.; Reed, D. E.

    2014-12-01

    Mediterranean water limited ecosystems are characterized by an heterogeneous spatial distribution of different plant functional types (PFT), such as grass and trees, competing for water use. Typically, during the dry summers, these ecosystems are characterized by a simple dual PFTs system with strong-resistant woody vegetation and bare soil, since grass died. The coupled use of sap flow measurements and eddy covariance technique is essential to estimate Evapotransiration (ET) in an heterogeneous ecosystem. An eddy covariance - micrometeorological tower has been installed since 2003 and 33 thermo-dissipation probes based on the Granier technique have installed at the Orroli site in Sardinia (Italy). The site landscape is a mixture of Mediterranean patchy vegetation types: wild olives, different shrubs and herbaceous species, which died during the summer. The sensors have been installed at the Orroli site into 15 wild olives clumps with different characteristics in terms of tree size, exposition to wind and solar radiation and soil depth. A network of 30 soil moisture sensors has also been installed for monitoring soil moisture spatial and temporal dynamics and their correlation with trees. Sap flow measurements show the significantly impacts on ET of soil moisture, radiation, vapor pressure deficit (VPD) and interestingly of tree position into the clump, showing double rates for the trees inside the wild olive clumps. The sap flow sensor outputs are analyzed for estimating innovative allometric relationships between sapwood area, diameter, canopy cover area, which are needed for the correct upscale of the local tree measurements to the site plot larger scale. Finally using an innovative scaling procedure, the sap-flow transpiration at field scale have been compared to the eddy covariance ET, showing the approximation of the eddy covariance technique. Finally the impact of environmental factors on ET for different soil depth and tree position is demonstrated.

  7. Assessing the role of soil water limitation in determining the Phytotoxic Ozone Dose (PODY) thresholds

    NASA Astrophysics Data System (ADS)

    De Marco, Alessandra; Sicard, Pierre; Fares, Silvano; Tuovinen, Juha-Pekka; Anav, Alessandro; Paoletti, Elena

    2016-12-01

    Phytotoxic Ozone Dose (PODY), defined as the accumulated stomatal ozone flux over a threshold of Y, is considered an optimal metric to evaluate O3 effects on vegetation. PODY is often computed through the DO3SE model, which includes species-specific parameterizations for the environmental response of stomatal conductance. However, the effect of soil water content (SWC) on stomatal aperture is difficult to model on a regional scale and thus often ignored. In this study, we used environmental input data obtained from the WRF-CHIMERE model for 14,546 grid-based forest sites in Southern Europe. SWC was obtained for the upper 10 cm of soil, which resulted in a worst-case risk scenario. PODY was calculated either with or without water limitation for different Y thresholds. Exclusion of the SWC effect on stomatal fluxes caused a serious overestimation of PODY. The difference increased with increasing Y (78%, 128%, 237% and 565% with Y = 0, 1, 2 and 3 nmol O3 m-2 s-1, respectively). This behaviour was confirmed by applying the same approach to field data measured in a Mediterranean Quercus ilex forest. WRF-CHIMERE overestimated SWC at this field site, so under real-world conditions the SWC effect may be larger than modelled. The differences were lower for temperate species (Pinus cembra 50-340%, P. sylvestris 57-363%, Abies alba 57-371%) than for Mediterranean species (P. pinaster 87-356%, P. halepensis 96-429%, P. pinea 107-532%, Q. suber 104-1602%), although a high difference was recorded also for the temperate species Fagus sylvatica with POD3 (524%). We conclude that SWC should be considered in PODY simulations and a low Y threshold should be used for robustness.

  8. The case for re-evaluating the upper limit value for selenium in drinking water in Europe.

    PubMed

    Barron, E; Migeot, V; Rabouan, S; Potin-Gautier, M; Séby, F; Hartemann, P; Lévi, Y; Legube, B

    2009-12-01

    Selenium is an essential trace element for life, which can be toxic for humans when intakes reach a certain amount. Therefore, since the margin between healthy intake and toxic intake is narrow, the selenium concentration of tap water is a parameter that must be monitored because of its potential for increased intake. The present work gives an overview of the different approaches used to calculate safe limits for selenium. As recommended by WHO, the guidelines for drinking water form the basis of national legislated standards for drinking water. Before setting a maximum acceptable level in drinking water, it is necessary to take into account the total intake of selenium in both food and beverage. The limit value of 10 microg l(-1) for drinking water laid down in the European regulations for all countries should be adapted depending on geographic area, as previously recommended by WHO.

  9. Wind River water restoration, Annual report November 2008 to October 2009.

    USGS Publications Warehouse

    Connolly, P.J.; Jezorek, I.G.; Munz, C.S.

    2010-01-01

    This report summarizes work completed by U.S. Geological Survey’s Columbia River Research Laboratory (USGS-CRRL) in the Wind River subbasin during the period November 2008 through October 2009 under Bonneville Power Administration (BPA) contract 41038. Long term research in the Wind River has focused on assessments of steelhead/rainbow trout Oncorhynchus mykiss populations, interactions with introduced populations of spring Chinook salmon O. tshawytscha and brook trout Salvelinus fontinalis, and influences of habitat variables on fish productivity. During this period, we collected water temperature data to characterize variation within and among tributaries and mainstem sections in the Trout Creek watershed, and assisted Washington Department of Fish and Wildlife with smolt trapping and tagging of smolt and parr steelhead with passive integrated transponder (PIT) tags. We also continued to maintain and test efficacy of a passive integrated transponder tag interrogation system (PTIS) in Trout Creek for assessing the adult steelhead runsize. We continued to maintain and download PTIS setups in the fish ladder at Hemlock Dam. These PTISs contributed information on movement and rearing of steelhead parr and smolts. A statement of work (SOW) was submitted to BPA in October 2009 that outlined work to be performed by USGS-CRRL. The SOW was organized by work elements, with each describing a research task. This report summarizes the progress completed under each work element.

  10. Natural mineral water of the United States: Section in Fourteenth Annual Report of the United States Geological Survey to the Secretary of the Interior, 1892-1893: Part 2 - Accompanying papers

    USGS Publications Warehouse

    Peale, A.C.

    1894-01-01

    Aside from the geological interest attached to the subject of mineral waters the facts that within the limits of the United States there are between 8,000 and 10,000 mineral springs, and that the waters from nearly 300 are annually placed upon the market to the extent of over 21,000,000 gallons, at a valuation of nearly \\$5,000,000, show plainly that the subject is also one of considerable economic importance. That this importance is an increasing one is evident when a comparison of these figures is made with the figures for 1883, the first year they were compiled. The production then was 7,529,423 gallons, with a valuation of \\$1,119,603, and the total number of springs known to be utilized for commercial purposes was only 189.

  11. Water resources data for Pennsylvania, water year 1996. Volume 2. Susquehanna and Potomac River basins. Water-data report (Annual), 1 October 1995-30 September 1996

    SciTech Connect

    Durlin, R.R.; Schaffstall, W.P.

    1997-07-01

    This report, Volume, 2, contains (1) discharge records for 81 continuous-record streamflow-gaging stations, 16 partial-record stations, and 20 special study and miscellaneous streamflow sites; (2) elevation and contents records for 12 lakes and reservoirs; (3) water-quality records for 7 gaging stations and 46 ungaged stream sites; and (4) water-level records for 30 ground-water network observation wells. Site locations are shown in figures throughout the report.

  12. Optimization and Annual Average Power Predictions of a Backward Bent Duct Buoy Oscillating Water Column Device Using the Wells Turbine.

    SciTech Connect

    Smith, Christopher S.; Bull, Diana L; Willits, Steven M.; Fontaine, Arnold A.

    2014-08-01

    This Technical Report presents work completed by The Applied Research Laboratory at The Pennsylvania State University, in conjunction with Sandia National Labs, on the optimization of the power conversion chain (PCC) design to maximize the Average Annual Electric Power (AAEP) output of an Oscillating Water Column (OWC) device. The design consists of two independent stages. First, the design of a floating OWC, a Backward Bent Duct Buoy (BBDB), and second the design of the PCC. The pneumatic power output of the BBDB in random waves is optimized through the use of a hydrodynamically coupled, linear, frequency-domain, performance model that links the oscillating structure to internal air-pressure fluctuations. The PCC optimization is centered on the selection and sizing of a Wells Turbine and electric power generation equipment. The optimization of the PCC involves the following variables: the type of Wells Turbine (fixed or variable pitched, with and without guide vanes), the radius of the turbine, the optimal vent pressure, the sizing of the power electronics, and number of turbines. Also included in this Technical Report are further details on how rotor thrust and torque are estimated, along with further details on the type of variable frequency drive selected.

  13. Remote sensing for evaluating crop water stress at field scale using infrared thermography: Potentials and limitations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past few decades, the competition for freshwater resources has substantially increased in arid/semi-arid areas, exacerbating the pressure on the largest user of water, namely agriculture, to consume less water. However, reducing crop consumptive water use or evapotranspiration through water...

  14. A two-layer soil moisture conceptual framework for exploring land surface-atmosphere interactions in water-limited ecosystem

    NASA Astrophysics Data System (ADS)

    Papuga, S. A.

    2014-12-01

    The exchange of water, energy, and carbon between the land surface and the atmosphere is largely influenced by vegetation. In turn, vegetation is strongly influenced by the partitioning of precipitation into evapotranspiration, soil moisture, and runoff. Ultimately, the hydrologic cycle exerts a strong control on the climate system. In fact, positive feedbacks between vegetation and the hydrologic cycle at small scales may have the ability to elicit non-linear responses with important large scale consequences. Therefore, capturing the synergies between hydrologic processes at different space and time scales is necessary for appropriately modeling the influence of vegetation and the hydrologic cycle on the climate system. Understanding the controls on land-atmosphere interactions and how they influence larger scale feedbacks will become increasingly important as climatic and other global changes continue to alter the water availability of our ecosystems. Water-limited ecosystems are especially sensitive to precipitation changes, and therefore insights concerning how their functioning responds to possible changes in precipitation patterns are important in understanding future climate scenarios. Over a decade of field work from my research group has highlighted the importance of deep soil moisture (from large storms) in the healthy functioning of water-limited ecosystems. This has led to the development of a two-layer soil moisture conceptual framework for exploring land surface-atmosphere interactions in water-limited ecosystems. Here I demonstrate how this framework can been used to link small scale processes investigated in field with large scale processes for water-limited ecosystems.

  15. Water Use Practices Limit the Effectiveness of a Temephos-Based Aedes aegypti Larval Control Program in Northern Argentina

    PubMed Central

    Garelli, Fernando M.; Espinosa, Manuel O.; Weinberg, Diego; Trinelli, María A.; Gürtler, Ricardo E.

    2011-01-01

    Background A five-year citywide control program based on regular application of temephos significantly reduced Aedes aegypti larval indices but failed to maintain them below target levels in Clorinda, northern Argentina. Incomplete surveillance coverage and reduced residuality of temephos were held as the main putative causes limiting effectiveness of control actions. Methodology The duration of temephos residual effects in household-owned water-holding tanks (the most productive container type and main target for control) was estimated prospectively in two trials. Temephos was applied using spoons or inside perforated small zip-lock bags. Water samples from the study tanks (including positive and negative controls) were collected weekly and subjected to larval mortality bioassays. Water turnover was estimated quantitatively by adding sodium chloride to the study tanks and measuring its dilution 48 hs later. Principal Findings The median duration of residual effects of temephos applied using spoons (2.4 weeks) was significantly lower than with zip-lock bags (3.4 weeks), and widely heterogeneous between tanks. Generalized estimating equations models showed that bioassay larval mortality was strongly affected by water type and type of temephos application depending on water type. Water type and water turnover were highly significantly associated. Tanks filled with piped water had high turnover rates and short-lasting residual effects, whereas tanks filled with rain water showed the opposite pattern. On average, larval infestations reappeared nine weeks post-treatment and seven weeks after estimated loss of residuality. Conclusions Temephos residuality in the field was much shorter and more variable than expected. The main factor limiting temephos residuality was fast water turnover, caused by householders' practice of refilling tanks overnight to counteract the intermittence of the local water supply. Limited field residuality of temephos accounts in part for the

  16. Annual and average estimates of water-budget components based on hydrograph separation and PRISM precipitation for gaged basins in the Appalachian Plateaus Region, 1900-2011

    USGS Publications Warehouse

    Nelms, David L.; Messinger, Terence; McCoy, Kurt J.

    2015-07-14

    As part of the U.S. Geological Survey’s Groundwater Resources Program study of the Appalachian Plateaus aquifers, annual and average estimates of water-budget components based on hydrograph separation and precipitation data from parameter-elevation regressions on independent slopes model (PRISM) were determined at 849 continuous-record streamflow-gaging stations from Mississippi to New York and covered the period of 1900 to 2011. Only complete calendar years (January to December) of streamflow record at each gage were used to determine estimates of base flow, which is that part of streamflow attributed to groundwater discharge; such estimates can serve as a proxy for annual recharge. For each year, estimates of annual base flow, runoff, and base-flow index were determined using computer programs—PART, HYSEP, and BFI—that have automated the separation procedures. These streamflow-hydrograph analysis methods are provided with version 1.0 of the U.S. Geological Survey Groundwater Toolbox, which is a new program that provides graphing, mapping, and analysis capabilities in a Windows environment. Annual values of precipitation were estimated by calculating the average of cell values intercepted by basin boundaries where previously defined in the GAGES–II dataset. Estimates of annual evapotranspiration were then calculated from the difference between precipitation and streamflow.

  17. Water-saving ground cover rice production system reduces net greenhouse gas fluxes in an annual rice-based cropping system

    NASA Astrophysics Data System (ADS)

    Yao, Z.; Du, Y.; Tao, Y.; Zheng, X.; Liu, C.; Lin, S.; Butterbach-Bahl, K.

    2014-11-01

    To safeguard food security and preserve precious water resources, the technology of water-saving ground cover rice production system (GCRPS) is being increasingly adopted for rice cultivation. However, changes in soil water status and temperature under GCRPS may affect soil biogeochemical processes that control the biosphere-atmosphere exchanges of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). The overall goal of this study is to better understand how net ecosystem greenhouse gas exchanges (NEGE) and grain yields are affected by GCRPS in an annual rice-based cropping system. Our evaluation was based on measurements of the CH4 and N2O fluxes and soil heterotrophic respiration (CO2 emissions) over a complete year, and the estimated soil carbon sequestration intensity for six different fertilizer treatments for conventional paddy and GCRPS. The fertilizer treatments included urea application and no N fertilization for both conventional paddy (CUN and CNN) and GCRPS (GUN and GNN), and solely chicken manure (GCM) and combined urea and chicken manure applications (GUM) for GCRPS. Averaging across all the fertilizer treatments, GCRPS increased annual N2O emission and grain yield by 40 and 9%, respectively, and decreased annual CH4 emission by 69%, while GCRPS did not affect soil CO2 emissions relative to the conventional paddy. The annual direct emission factors of N2O were 4.01, 0.09 and 0.50% for GUN, GCM and GUM, respectively, and 1.52% for the conventional paddy (CUN). The annual soil carbon sequestration intensity under GCRPS was estimated to be an average of -1.33 Mg C ha-1 yr-1, which is approximately 44% higher than the conventional paddy. The annual NEGE were 10.80-11.02 Mg CO2-eq ha-1 yr-1 for the conventional paddy and 3.05-9.37 Mg CO2-eq ha-1 yr-1 for the GCRPS, suggesting the potential feasibility of GCRPS in reducing net greenhouse effects from rice cultivation. Using organic fertilizers for GCRPS considerably reduced annual emissions of CH4

  18. Water-saving ground cover rice production system reduces net greenhouse gas fluxes in an annual rice-based cropping system

    NASA Astrophysics Data System (ADS)

    Yao, Z.; Du, Y.; Tao, Y.; Zheng, X.; Liu, C.; Lin, S.; Butterbach-Bahl, K.

    2014-06-01

    To safeguard food security and preserve precious water resources, the technology of water-saving ground cover rice production system (GCRPS) is being increasingly adopted for the rice cultivation. However, changes in soil water status and temperature under GCRPS may affect soil biogeochemical processes that control the biosphere-atmosphere exchanges of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). The overall goal of this study is to better understand how net ecosystem greenhouse gas exchanges (NEGE) and grain yields are affected by GCRPS in an annual rice-based cropping system. Our evaluation was based on measurements of the CH4 and N2O fluxes and soil heterotrophic respiration (CO2 emission) over a complete year, as well as the estimated soil carbon sequestration intensity for six different fertilizer treatments for conventional paddy and GCRPS. The fertilizer treatments included urea application and no N fertilization for both conventional paddy (CUN and CNN) and GCRPS (GUN and GNN), solely chicken manure (GCM) and combined urea and chicken manure applications (GUM) for GCRPS. Averaging across all the fertilizer treatments, GCRPS increased annual N2O emission and grain yield by 40% and 9%, respectively, and decreased annual CH4 emission by 69%, while GCRPS did not affect soil CO2 emissions relative to the conventional paddy. The annual direct emission factors of N2O were 4.01, 0.087 and 0.50% for GUN, GCM and GUM, respectively, and 1.52% for the conventional paddy (CUN). The annual soil carbon sequestration intensity under GCRPS was estimated to be an average of -1.33 Mg C ha-1 yr-1, which is approximately 44% higher than the conventional paddy. The annual NEGE were 10.80-11.02 Mg CO2-eq ha-1 yr-1 for the conventional paddy and 3.05-9.37 Mg CO2-eq ha-1 yr-1 for the GCRPS, suggesting the potential feasibility of GCRPS in reducing net greenhouse effect from rice cultivation. Using organic fertilizers for GCRPS considerably reduced annual emissions

  19. Ground Water Quality and Riparian Enhancement Projects in Sherman County, Oregon; Coordination and Technical Assistance, 2003-2004 Annual Report.

    SciTech Connect

    Faucera, Jason

    2004-05-01

    This project was designed to provide technical assistance and project coordination to producers in Sherman County for on the ground water quality and riparian enhancement projects. This is accomplished utilizing the USDA Conservation Reserve Enhancement Program (CREP) in addition to other grant monies to translate the personnel funds in this project to on the ground projects. Two technicians and one watershed council coordinator are funded, either wholly or in part, by funds from this grant. The project area encompasses the whole of Sherman County which is bordered almost entirely by streams providing habitat or migration corridors for endangered fish species including steelhead and Chinook salmon. Of those four streams that comprise Sherman County's boundaries, three are listed on the DEQ 303(d) list of water quality limited streams for exceeding summer temperature limits. Only one stream in the interior of Sherman County is 303(d) listed for temperatures, but is the largest watershed in the County. Temperatures in streams are directly affected by the amount of solar radiation allowed to reach the surface of the water. Practices designed to improve bank-side vegetation, such as the CREP program, will counteract the solar heating of those water quality listed streams, benefiting endangered stocks. CREP and water quality projects are promoted and coordinated with local landowners through locally-led watershed councils. Funding from BPA provides a portion of the salary for a watershed council coordinator who acts to disseminate water quality and USDA program information directly to landowners through watershed council activities. The watershed coordinator acts to educate landowners in water quality and riparian management issues and to secure funds for the implementation of on the ground water quality projects. Actual project implementation is carried out by the two technicians funded by this project. Technicians in Sherman County, in cooperation with the USDA

  20. Ground Water Quality and Riparian Enhancement Projects in Sherman County, Oregon; Coordination and Technical Assistance, 2005-2006 Annual Report.

    SciTech Connect

    Faucera, Jason

    2006-06-01

    This project was designed to provide technical assistance and project coordination to producers in Sherman County for on the ground water quality and riparian enhancement projects. This is accomplished utilizing the USDA Conservation Reserve Enhancement Program (CREP) in addition to other grant monies to translate the personnel funds in this project to on the ground projects. Two technicians and one watershed council coordinator are funded, either wholly or in part, by funds from this grant. The project area encompasses the whole of Sherman County which is bordered almost entirely by streams providing habitat or migration corridors for endangered fish species including steelhead and Chinook salmon. Of those four streams that comprise Sherman County's boundaries, three are listed on the DEQ 303(d) list of water quality limited streams for exceeding summer temperature limits. Only one stream in the interior of Sherman County is 303(d) listed for temperatures, but is the largest watershed in the County. Temperatures in streams are directly affected by the amount of solar radiation allowed to reach the surface of the water. Practices designed to improve bank-side vegetation, such as the CREP program, will counteract the solar heating of those water quality listed streams, benefiting endangered stocks. CREP and water quality projects are promoted and coordinated with local landowners through locally-led watershed councils. Funding from BPA provides a portion of the salary for a watershed council coordinator who acts to disseminate water quality and USDA program information directly to landowners through watershed council activities. The watershed coordinator acts to educate landowners in water quality and riparian management issues and to secure funds for the implementation of on the ground water quality projects. Actual project implementation is carried out by the two technicians funded by this project. Technicians in Sherman County, in cooperation with the USDA

  1. Ground Water Quality and Riparian Enhancement Projects in Sherman County, Oregon; Coordination and Technical Assistance, 2002-2003 Annual Report.

    SciTech Connect

    Faucera, Jason

    2003-06-23

    This project was designed to provide project coordination and technical assistance to producers in Sherman County for on the ground water quality enhancement and riparian enhancement projects. This is accomplished utilizing the USDA Conservation Enhancement Reserve Program (CREP) and other grant monies to translate the personnel funds in this project to on the ground projects. Two technicians and one watershed council coordinator are funded, either wholly or in part, by funds from this grant. The project area encompasses the whole of Sherman County which is bordered almost entirely by streams providing habitat or migration corridors for endangered fish species including steelhead and Chinook salmon. Three of those four streams and one other major Sherman County stream are listed on the DEQ 303(d) list of water quality limited streams for exceeding summer temperature limits. Temperature in streams are directly affected by the amount of solar radiation allowed to reach the surface of the water. Practices designed to improve bank-side vegetation, such as the CREP program, will counteract the solar heating of those water quality listed streams, benefiting endangered stocks. CREP and water quality projects are promoted and coordinated with local landowners through locally-led watershed councils. Funding from BPA provides a portion of the salary for a watershed council coordinator who acts to disseminate water quality and USDA program information directly to landowners through watershed council activities. The watershed coordinator acts to educate landowners in water quality and riparian management issues and to secure funds for the implementation of on the ground water quality projects. Actual project implementation is carried out by the two technicians funded by this project. Technicians in Sherman County, in cooperation with the USDA Natural Resources Conservation Service, assist landowners in developing Resource Management Systems (RMS) that address resource concerns

  2. Ground Water Quality and Riparian Enhancement Projects in Sherman County, Oregon : Coordination and Technical Assistance, 2004-2005 Annual Report.

    SciTech Connect

    Faucera, Jason

    2005-06-01

    This project was designed to provide technical assistance and project coordination to producers in Sherman County for on the ground water quality and riparian enhancement projects. This is accomplished utilizing the USDA Conservation Reserve Enhancement Program (CREP) in addition to other grant monies to translate the personnel funds in this project to on the ground projects. Two technicians and one watershed council coordinator are funded, either wholly or in part, by funds from this grant. The project area encompasses the whole of Sherman County which is bordered almost entirely by streams providing habitat or migration corridors for endangered fish species including steelhead and Chinook salmon. Of those four streams that comprise Sherman County's boundaries, three are listed on the DEQ 303(d) list of water quality limited streams for exceeding summer temperature limits. Only one stream in the interior of Sherman County is 303(d) listed for temperatures, but is the largest watershed in the County. Temperatures in streams are directly affected by the amount of solar radiation allowed to reach the surface of the water. Practices designed to improve bank-side vegetation, such as the CREP program, will counteract the solar heating of those water quality listed streams, benefiting endangered stocks. CREP and water quality projects are promoted and coordinated with local landowners through locally-led watershed councils. Funding from BPA provides a portion of the salary for a watershed council coordinator who acts to disseminate water quality and USDA program information directly to landowners through watershed council activities. The watershed coordinator acts to educate landowners in water quality and riparian management issues and to secure funds for the implementation of on the ground water quality projects. Actual project implementation is carried out by the two technicians funded by this project. Technicians in Sherman County, in cooperation with the USDA

  3. When water saving limits recycling: Modelling economy-wide linkages of wastewater use.

    PubMed

    Luckmann, Jonas; Grethe, Harald; McDonald, Scott

    2016-01-01

    The reclamation of wastewater is an increasingly important water source in parts of the world. It is claimed that wastewater recycling is a cheap and reliable form of water supply, which preserves water resources and is economically efficient. However, the quantity of reclaimed wastewater depends on water consumption by economic agents connected to a sewage system. This study uses a Computable General Equilibrium (CGE) model to analyse such a cascading water system. A case study of Israel shows that failing to include this linkage can lead to an overestimation of the potential of wastewater recycling, especially when economic agents engage in water saving.

  4. Coupling of water and carbon transport in trees: -Could water limitations of phloem transport speed up carbon starvation and tree mortality?

    NASA Astrophysics Data System (ADS)

    Sevanto, S.; McDowell, N. G.; Dickman, L. T.; Pangle, R.; Pockman, W.

    2011-12-01

    Understanding the mechanisms behind tree mortality is increasingly important because climate change appears to be increasing drought severity and duration worldwide, with concomitant increases in mortality. Carbon starvation is one of the mechanisms suggested to be responsible for mortality, especially for species that close stomata at low xylem water tensions. Such plants would be under negative carbon balance during drought. Carbohydrate transport in plants relies on the availability of apoplastic water and therefore, shortage of water could lead to inability to distribute sugars and speed up carbon starvation even if carbohydrate reserves existed. To test these ideas we conducted a greenhouse study where pinon pine (Pinus edulis) trees were killed using two treatments: water limitation (complete drought) and carbon limitation (complete darkness). We collected tissue samples for non-structural carbohydrate content analysis weekly and monitored changes in xylem and phloem water potentials using stem diameter variation measurements. To follow changes in the physiological status of the trees we measured shoot gas exchange, leaf water potential and sap flow rate. Carbon-limited trees continued respiring at relatively high rates and maintained both xylem and phloem transport despite rapidly diminishing carbohydrate pools. Water-limited trees, on the other hand, exhibited reduced respiration and xylem and phloem transport rates as soon as drought inhibited stomatal opening; even before any significant drop in leaf water potential. This suggests that respirationmetabolic rate is strongly controlled by soil water availability, and instead of speeding up mortality, reduced carbohydrate transport and utilization rate may be a valuable strategy to enhance tree survival during long droughts.

  5. Developing an Eco-hydrological Model for Exploring the Vegetation-water Interactions in Water-limited Regions

    NASA Astrophysics Data System (ADS)

    Jiao, Y.; Lei, H.; Yang, D.

    2013-12-01

    In recent decades, lots of land surface models have been developed and widely used for climate change and hydrology studies. These models usually provide comprehensive information for understanding the vertical eco-hydrological processes within a grid. However, the simplification (or neglect) of river network and river routine in the models may lead to large uncertainty in studying the river discharge-vegetation interactions. On the contrary, distributed hydrological models mainly specialize the description of watershed and the parameterization of river routine, while usually simplify the vertical eco-hydrological processes. In this study, we aim at developing a new eco-hydrological model which combines the advantages of both types of model, in order to explore the interactions among river discharge, vegetation, and climate in water-limited watersheds. The new model is developed based on Community Land Model 4 (CLM4) and Geomorphology Based Hydrological Model (GBHM). CLM4 is a commonly used and typical land surface model, while GBHM is a distributed hydrological model that has been applied in a number of watersheds in China and Japan for simulating the river discharge. Wudinghe River Basin, located in the middle reach of the Yellow River with a drainage area of 28706 km2, is selected for our case study. Meteorological data from 12 meteorological stations and 91 rain gauges are collected and interpolated to generate forcing data, while land use map in year 2000, LAI from 1981 to 2010, soil hydraulic parameter dataset, and 90m SRTM DEM are obtained as surface parameters. Daily observed stream flow data are used for model calibration and validation. First, we establish both models at a resolution of 0.01 degree (about 1km) in the basin, and evaluate the models using observed stream flow to demonstrate their merits and demerits. Second, we couple them to develop a new eco-hydrological model by substituting the river routine module of CLM4 with the river routing module

  6. Using models to guide field experiments: a priori predictions for the CO 2 response of a nutrient- and water-limited native Eucalypt woodland

    DOE PAGES

    Medlyn, Belinda E.; De Kauwe, Martin G.; Zaehle, Sönke; ...

    2016-05-09

    One major uncertainty in Earth System models is the response of terrestrial ecosystems to rising atmospheric CO2 concentration (Ca), particularly under nutrient-lim- ited conditions. The Eucalyptus Free-Air CO2 Enrichment (EucFACE) experiment, recently established in a nutrient- and water-limited woodlands, presents a unique opportunity to address this uncertainty, but can best do so if key model uncertainties have been identified in advance. Moreover, we applied seven vegetation models, which have previously been comprehensively assessed against earlier forest FACE experi- ments, to simulate a priori possible outcomes from EucFACE. Our goals were to provide quantitative projections against which to evaluate data asmore » they are collected, and to identify key measurements that should be made in the experiment to allow discrimination among alternative model assumptions in a postexperiment model intercompari- son. Simulated responses of annual net primary productivity (NPP) to elevated Ca ranged from 0.5 to 25% across models. The simulated reduction of NPP during a low-rainfall year also varied widely, from 24 to 70%. Key processes where assumptions caused disagreement among models included nutrient limitations to growth; feedbacks to nutri- ent uptake; autotrophic respiration; and the impact of low soil moisture availability on plant processes. Finally, knowledge of the causes of variation among models is now guiding data collection in the experiment, with the expectation that the experimental data can optimally inform future model improvements.« less

  7. Effects of water regime during rice-growing season on annual direct N(2)O emission in a paddy rice-winter wheat rotation system in southeast China.

    PubMed

    Liu, Shuwei; Qin, Yanmei; Zou, Jianwen; Liu, Qiaohui

    2010-01-15

    Annual paddy rice-winter wheat rotation constitutes one of the typical cropping systems in southeast China, in which various water regimes are currently practiced during the rice-growing season, including continuous flooding (F), flooding-midseason drainage-reflooding (F-D-F), and flooding-midseason drainage-reflooding and moisture but without waterlogging (F-D-F-M). We conducted a field experiment in a rice-winter wheat rotation system to gain an insight into the water regime-specific emission factors and background emissions of nitrous oxide (N(2)O) over the whole annual cycle. While flooding led to an unpronounced N(2)O emission during the rice-growing season, it incurred substantial N(2)O emission during the following non-rice season. During the non-rice season, N(2)O fluxes were, on average, 2.61 and 2.48 mg N(2)O-Nm(-)(2) day(-1) for the 250 kg N ha(-1) applied plots preceded by the F and F-D-F water regimes, which are 56% and 49% higher than those by the F-D-F-M water regime, respectively. For the annual rotation system experienced by continuous flooding during the rice-growing season, the relationship between N(2)O emission and nitrogen input predicted the emission factor and background emission of N(2)O to be 0.87% and 1.77 kg N(2)O-Nha(-1), respectively. For the plots experienced by the water regimes of F-D-F and F-D-F-M, the emission factors of N(2)O averaged 0.97% and 0.85%, with background N(2)O emissions of 2.00 kg N(2)O-Nha(-1) and 1.61 kg N(2)O-Nha(-1) for the annual rotation system, respectively. Annual direct N(2)O-N emission was estimated to be 98.1 Gg yr(-1) in Chinese rice-based cropping systems in the 1990s, consisting of 32.3 Gg during the rice-growing season and 65.8 Gg during the non-rice season, which accounts for 25-35% of the annual total emission from croplands in China.

  8. A comparison of additional treatment processes to limit particle accumulation and microbial growth during drinking water distribution.

    PubMed

    Liu, G; Lut, M C; Verberk, J Q J C; Van Dijk, J C

    2013-05-15

    Water quality changes, particle accumulation and microbial growth occurring in pilot-scale water distribution systems fed with normally treated and additional treated groundwater were monitored over a period of almost one year. The treatment processes were ranked in the following order: nanofiltration (NF) > (better than) ultrafiltration (UF) > ion exchange (IEX) for limiting particle accumulation. A different order was found for limiting overall microbial growth: NF > IEX > UF. There were strong correlations between particle load and particle accumulation, and between nutrient load and microbial growth. It was concluded that particle accumulation can be controlled by reducing the particle load in water treatment plants; and the microbial growth can be better controlled by limiting organic nutrients rather than removing biomass in water treatment plants. The major focus of this study was on microbial growth. The results demonstrated that growth occurred in all types of treated water, including the phases of bulk water, biofilm and loose deposits. Considering the growth in different phases, similar growth in bulk water was observed for all treatments; NF strongly reduced growth both in loose deposits and in biofilm; UF promoted growth in biofilm, while strongly limiting growth in loose deposits. IEX had good efficiency in between UF and NF, limiting both growths in loose deposits and in biofilm. Significant growth was found in loose deposits, suggesting that loose deposit biomass should be taken into account for growth evaluation and/or prediction. Strong correlations were found between microbial growth and pressure drop in a membrane fouling simulator which proved that a membrane fouling simulator can be a fast growth predictor (within a week). Different results obtained by adenosine triphosphate and flow cytometry cell counts revealed that ATP can accurately describe both suspended and particle-associated biomass, and flow cytometry files of TCC measurements needs

  9. 33 CFR 328.5 - Changes in limits of waters of the United States.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... also change the boundaries of the waters of the United States. For example, changing sea levels or... alterations of the boundaries of waters of the United States. Gradual changes which are due to natural...

  10. 33 CFR 328.5 - Changes in limits of waters of the United States.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... also change the boundaries of the waters of the United States. For example, changing sea levels or... alterations of the boundaries of waters of the United States. Gradual changes which are due to natural...

  11. 33 CFR 328.5 - Changes in limits of waters of the United States.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... also change the boundaries of the waters of the United States. For example, changing sea levels or... alterations of the boundaries of waters of the United States. Gradual changes which are due to natural...

  12. New steady-state models for water-limited cropping systems using saline irrigation waters: Analytical solutions and applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mode...

  13. New steady-state models for water-limited cropping systems using saline irrigation waters: Analytical solutions and applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mod...

  14. 33 CFR 328.5 - Changes in limits of waters of the United States.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... also change the boundaries of the waters of the United States. For example, changing sea levels or subsidence of land may cause some areas to become waters of the United States while siltation or a change in... alterations of the boundaries of waters of the United States. Gradual changes which are due to natural...

  15. 33 CFR 328.5 - Changes in limits of waters of the United States.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... also change the boundaries of the waters of the United States. For example, changing sea levels or subsidence of land may cause some areas to become waters of the United States while siltation or a change in... alterations of the boundaries of waters of the United States. Gradual changes which are due to natural...

  16. Measurement and Modeling of Energetic Material Mass Transfer to Soil Pore Water - Project CP-1227 Annual Technical Report

    SciTech Connect

    PHELAN, JAMES M.; WEBB, STEPHEN W.; ROMERO, JOSEPH V.; BARNETT, JAMES L.; GRIFFIN, FAWN A.

    2003-01-01

    Military test and training ranges operate with live fire engagements to provide realism important to the maintenance of key tactical skills. Ordnance detonations during these operations typically produce minute residues of parent explosive chemical compounds. Occasional low order detonations also disperse solid phase energetic material onto the surface soil. These detonation remnants are implicated in chemical contamination impacts to groundwater on a limited set of ranges where environmental characterization projects have occurred. Key questions arise regarding how these residues and the environmental conditions (e.g. weather and geostratigraphy) contribute to groundwater pollution impacts. This report documents interim results of experimental work evaluating mass transfer processes from solid phase energetics to soil pore water. The experimental work is used as a basis to formulate a mass transfer numerical model, which has been incorporated into the porous media simulation code T2TNT. Experimental work to date with Composition B explosive has shown that column tests typically produce effluents near the temperature dependent solubility limits for RDX and TNT. The influence of water flow rate, temperature, porous media saturation and mass loading is documented. The mass transfer model formulation uses a mass transfer coefficient and surface area function and shows good agreement with the experimental data. Continued experimental work is necessary to evaluate solid phase particle size and 2-dimensional effects, and actual low order detonation debris. Simulation model improvements will continue leading to a capability to complete screening assessments of the impacts of military range operations on groundwater quality.

  17. Water quality, streamflow conditions, and annual flow-duration curves for streams of the San Juan–Chama Project, southern Colorado and northern New Mexico, 1935-2010

    USGS Publications Warehouse

    Falk, Sarah E.; Anderholm, Scott K.; Hafich, Katya A.

    2013-01-01

    The Albuquerque–Bernalillo County Water Utility Authority supplements the municipal water supply for the Albuquerque metropolitan area, in central New Mexico, with water diverted from the Rio Grande. Water diverted from the Rio Grande for municipal use is derived from the San Juan–Chama Project, which delivers water from streams in the southern San Juan Mountains in the Colorado River Basin in southern Colorado to the Rio Chama watershed and the Rio Grande Basin in northern New Mexico. The U.S. Geological Survey, in cooperation with Albuquerque–Bernalillo County Water Utility Authority, has compiled historical streamflow and water-quality data and collected new water-quality data to characterize the water quality and streamflow conditions and annual flow variability, as characterized by annual flow-duration curves, of streams of the San Juan–Chama Project. Nonparametric statistical methods were applied to calculate annual and monthly summary statistics of streamflow, trends in streamflow conditions were evaluated with the Mann–Kendall trend test, and annual variation in streamflow conditions was evaluated with annual flow-duration curves. The study area is located in northern New Mexico and southern Colorado and includes the Rio Blanco, Little Navajo River, and Navajo River, tributaries of the San Juan River in the Colorado River Basin located in the southern San Juan Mountains, and Willow Creek and Horse Lake Creek, tributaries of the Rio Chama in the Rio Grande Basin. The quality of water in the streams in the study area generally varied by watershed on the basis of the underlying geology and the volume and source of the streamflow. Water from the Rio Blanco and Little Navajo River watersheds, primarily underlain by volcanic deposits, volcaniclastic sediments and landslide deposits derived from these materials, was compositionally similar and had low specific-conductance values relative to the other streams in the study area. Water from the Navajo River

  18. Influence of seasonal and inter-annual hydro-meteorological variability on surface water fecal coliform concentration under varying land-use composition.

    PubMed

    St Laurent, Jacques; Mazumder, Asit

    2014-01-01

    Quantifying the influence of hydro-meteorological variability on surface source water fecal contamination is critical to the maintenance of safe drinking water. Historically, this has not been possible due to the scarcity of data on fecal indicator bacteria (FIB). We examined the relationship between hydro-meteorological variability and the most commonly measured FIB, fecal coliform (FC), concentration for 43 surface water sites within the hydro-climatologically complex region of British Columbia. The strength of relationship was highly variable among sites, but tended to be stronger in catchments with nival (snowmelt-dominated) hydro-meteorological regimes and greater land-use impacts. We observed positive relationships between inter-annual FC concentration and hydro-meteorological variability for around 50% of the 19 sites examined. These sites are likely to experience increased fecal contamination due to the projected intensification of the hydrological cycle. Seasonal FC concentration variability appeared to be driven by snowmelt and rainfall-induced runoff for around 30% of the 43 sites examined. Earlier snowmelt in nival catchments may advance the timing of peak contamination, and the projected decrease in annual snow-to-precipitation ratio is likely to increase fecal contamination levels during summer, fall, and winter among these sites. Safeguarding drinking water quality in the face of such impacts will require increased monitoring of FIB and waterborne pathogens, especially during periods of high hydro-meteorological variability. This data can then be used to develop predictive models, inform source water protection measures, and improve drinking water treatment.

  19. New steady-state models for water-limited cropping systems using saline irrigation waters: Analytical solutions and applications

    NASA Astrophysics Data System (ADS)

    Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

    2014-12-01

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two new explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess clear advantages over available alternatives, including: (i) the new solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the new analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

  20. The effect of limited options and policy interactions on water storage policy in south Florida.

    PubMed

    Mayer, A L

    2001-09-01

    Due to environmental constraints and reactive water management practices, water shortages exist across the Everglades ecosystem. A growing human population and continued wetlands damage and loss decrease the system's ability to provide water for sustained natural areas and for human uses. 'The Restudy' is an $8 billion plan to restore the Everglades while also continuing to provide water storage for urban and agricultural areas. The Restudy proposes a mix of water storage systems to provide for the predicted future growth in water demand. This mix is purported to be the most cost-efficient at providing water supplies, within the constraints of unchanged agricultural and urban land use. However, a sensitivity analysis of the Restudy's cost equation reveals that the total cost of water storage systems is influenced by real estate, land acquisition and water treatment costs. The interaction of land use and agricultural policies can affect these cost factors, and can change the relative cost-efficiency between storage systems. Real estate and land acquisition costs are affected by several 1996 Farm Bill provisions, which influence the cost of aboveground water storage systems versus Aquifer Storage and Recovery systems. The Governor's Commission for a Sustainable South Florida recommendations also influence the water storage options available to the Restudy. Due to the Restudy's initial assumptions and constraints, it may not advocate the most economically and ecologically sound remediation.