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Water temperature influences most physical and biological processes in streams, and along with streamflows is a major driver of ecosystem processes. Collecting data to measure water temperature is therefore imperative, and relatively straightforward. Several protocols exist for collecting stream temperature data, but these are frequently directed towards specialists. This document was developed to address the need for a protocol intended for non-specialists (non-aquatic) staff. It provides specific step-by-step procedures on (1) how to launch data loggers, (2) check the factory calibration of data loggers prior to field use, (3) how to install data loggers in streams for year-round monitoring, (4) how to download...
Categories: Publication; Types: Citation; Tags: Techniques and Methods
Agricultural nitrogen is a major contributor to Gulf of Mexico hypoxia, and research has shown that agricultural subsurface tile drainage is a major carrier of nitrogen from croplands to streams and rivers. This study compares the results of abating nitrogen under a retired-land minimization policy with those of a net revenue- maximizing policy, paying particular attention to the role of tile-drained land. Endings reveal the retirement-minimizing policy resulted in more tile-drained land being retired and less being fertilizer-managed than was optimal under the net-return maximizing policy. Also, it led to a greater economic burden being shouldered by tile- drained land. Under both cases, tile drainage dominated...
The use of conservation practices by agriculture in the United States will enhance soil organic carbon and potentially increase carbon sequestration. This, in turn, will decrease the net emission of carbon dioxide. A number of studies exist that calibrate the contribution of various individual, site-specific conservation practices on changes in soil organic carbon. There is a general absence, however, of a comprehensive effort to measure objectively the contribution of these practices including conservation tillage, the Conservation Reserve Program, and conservation buffer strips to an change in soil organic carbon. This paper fills that void. After recounting the evolution of the use of the various conservation...
Increased atmospheric CO sub(2) concentration and climate change may significantly impact the hydrological and meteorological processes of a watershed system. Quantifying and understanding hydrological responses to elevated ambient CO sub(2) and climate change is, therefore, critical for formulating adaptive strategies for an appropriate management of water resources. In this study, the Soil and Water Assessment Tool (SWAT) model was applied to assess the effects of increased CO sub(2) concentration and climate change in the Upper Mississippi River Basin (UMRB). The standard SWAT model was modified to represent more mechanistic vegetation type specific responses of stomatal conductance reduction and leaf area increase...
A study of the quality of ground water beneath irrigated cropland was completed for the northern and southern High Plains aquifer. Ground-water samples were collected from 30 water-table monitoring wells in the northern agricultural land-use (NAL) study area in Nebraska in 2004 and 29 water-table monitoring wells in the southern agricultural land-use (SAL) study area in Texas in 2003. The two study areas represented different agricultural and hydrogeologic settings. The primary crops grown in the NAL study area were corn and soybeans, and the primary crop in the SAL study area was cotton. Overall, pesticide and fertilizer application rates were larger in the NAL study area. Also, precipitation and recharge rates...
ABSTRACT Catchment-modelling techniques, although not yet widely used in biological contexts, may be a valuable tool in the management and conservation of stream fishes. This study was undertaken to evaluate the potential of a catchment-scale hydrologic model, the Soil and Water Assessment Tool (SWAT), to explain characteristics of stream fish assemblages and to enhance current field-based stream assessments., Stream fish assemblages, instream habitat, geomorphology, and water quality were surveyed in 16 study catchments in Ohio, USA. Subsequently, SWAT was used to model stream discharge, sediment flux and concentration, and nitrogen and phosphorus yields for each catchment., Principal component analysis (PCA) and...
The state of Iowa requires developing total maximum daily loads (TMDLs) for over 400 water bodies that are listed on the 303(d) list of the impaired waters. The Raccoon River watershed, which covers approximately 9400 km2 of prime agriculture land and represents a typical Midwestern corn-belt region in west-central Iowa, was found to have three stream segments impaired by nitrate-N. The Soil and Water Assessment Tool (SWAT) was applied to this watershed to facilitate the development of a TMDL. The modeling framework integrates SWAT with supporting software and databases on topography, land use and management, soil, and weather information. Annual and monthly simulated and measured streamflow and nitrate loads were...
Societies are facing major challenges in allocating water resources to growing water demands due to population growth and industrial and agricultural developments. With increasing water scarcity, the need to increase agricultural water productivity is receiving significant attention in developing countries. Among alternative options for meeting increasing water demand, improving productivity has received considerable attention. Therefore, planning of water systems to face future development conditions needs further studies on land, water use, and resources as well as consideration of objectives to maximize crop production to achieve the maximum net return. Because climate change is likely to have impact on the hydrological...
A five-year record of streamflow and chemical sampling data was evaluated to assess the effects of large-scale prairie restoration on transport of NO3–N, Cl, and SO4 loads from paired 5000-ha watersheds located in Jasper County, Iowa. Water quality conditions monitored during land use conversion from row crop agriculture to native prairie in the Walnut Creek watershed were compared with a highly agricultural control watershed (Squaw Creek). Combining hydrograph separation with a load estimation program, baseflow and stormflow loads of NO3–N, Cl, and SO4 were estimated at upstream and downstream sites on Walnut Creek and a downstream site on Squaw Creek. Chemical export in both watersheds was found to occur primarily...
The determination of best management practices for land resources is often complicated by the lack of a means for evaluation and lack of quality data. Soil surveys are an important source of data that can be used to improve farm and ranch planning and environmental protection. In this study, we examined the use of a soil survey geographic (SSURGO) database within a geographic information system (GIS) coupled with remote sensing data for land-use management in Finney County, Kansas. The objectives were (i) to identify land-use change; (ii) to evaluate the influence of soil, groundwater, and physiography on land use; and (iii) to assess land-use potential and present management alternatives. Land-use/land-cover (LULC)...
There have been growing concerns over the negative effect of pesticide usage on human health and environmental sustainability. It has been found out that atrazine, a widely used herbicide, threatens ecosystems. Its residues after application can be discharged into water bodies, and thus contaminate surface water and pose risks to public health. An integrated modelling system was developed to estimate atrazine losses through surface runoff. This model includes a distributed hydrological model, a pesticide adsorption model, relational databases, and a geographic information system. The proposed model can simulate atrazine losses due to runoff through the consideration of emission, degradation, adsorption, and movement...
Streamflow declines on the Great Plains of the US are causing many Federal reservoirs to become profoundly inefficient, and will eventually drive them into unsustainability as negative annual reservoir water budgets become more common. The streamflow declines are historically related to groundwater mining, but since the mid-1980s correlate increasingly with climate. This study highlights that progression toward unsustainability, and shows that future climate change will continue streamflow declines at historical rates, with severe consequences for surface water supply. An object lesson is Optima Lake in the Oklahoma Panhandle, where streamflows have declined 99% since the 1960s and the reservoir has never been more...
Publicly available statistics regarding rural demographics, rural society and land use are presented and analysed using Geographic Information System (GIS). Our aim was to provide a quantitative basis for discussion of rural policy issues such as urban encroachment. Productivity (tonnage) of crop agriculture has increased by about 230% over 40 years while that of livestock (expressed as livestock units) has remained constant. Agricultural consolidation and intensification seen in southern Ontario has not translated into economic sustainability where on-farm income declined from 1991 to 2000. However, on-farm income in southern Quebec and municipalities adjacent to Toronto increased, perhaps due to the niche markets...
Abstract (from http://www.springer.com/us/book/9789400775145): This volume offers a scientific assessment of the effects of climatic variability and change on forest resources in the United States. Derived from a report that provides technical input to the 2013 U.S. Global Change Research Program National Climate Assessment, the book serves as a framework for managing U.S. forest resources in the context of climate change. The authors focus on topics having the greatest potential to alter the structure and function of forest ecosystems, and therefore ecosystem services, by the end of the 21st century. Part I provides an environmental context for assessing the effects of climate change on forest resources, summarizing...
Categories: Publication; Types: Citation; Tags: North Central CASC, Other Tools
Renewable fuel production, particularly grain-based ethanol, is expanding rapidly in the USA. Although subsidized grain-based ethanol may provide a competitively priced transportation fuel, concerns exist about potential environmental impacts. This contribution focuses on potential water quality implications of expanded grain-based ethanol production and potential impacts of perennial-grass–based cellulosic ethanol. Expanded grain-based ethanol will increase and intensify corn production. Even with recommended fertilizer and land conservation measures, corn acreage can be a major source of N loss to water (20–40 kg ha-1 yr-1). A greater acreage of corn is estimated to increase N and P loss to water by 37% (117 million...
Whitefish Lake, which is officially named Bardon Lake, is an oligotrophic, soft-water seepage lake in northwestern Wisconsin, and classified by the Wisconsin Department of Natural Resources as an Outstanding Resource Water. Ongoing monitoring of the lake demonstrated that its water quality began to degrade (increased phosphorus and chlorophyll a concentrations) around 2002 following a period of high water level. To provide a better understanding of what caused the degradation in water quality, and provide information to better understand the lake and protect it from future degradation, the U.S. Geological Survey did a detailed study from 2004 to 2008. The goals of the study were to describe the past and present...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/2016GB005493/abstract): Phytoplankton growth in the Gulf of Alaska (GoA) is limited by iron (Fe), yet Fe sources are poorly constrained. We examine the temporal and spatial distributions of Fe, and its sources in the GoA, based on data from three cruises carried out in 2010 from the Copper River (AK) mouth to beyond the shelf break. April data are the first to describe late winter Fe behavior before surface water nitrate depletion began. Sediment resuspension during winter and spring storms generated high “total dissolvable Fe” (TDFe) concentrations of ~1000 nmol kg−1 along the entire continental shelf, which decreased beyond the shelf break. In July, high...
Quantitative biological assessment protocols are needed for monitoring river status and evaluating river rehabilitation efforts. We conducted a standardized macroinvertebrate survey at 100 sites on 38 nonwadeable rivers in Wisconsin to construct, test, and apply an index of biotic integrity (IBI) intended to be such a bioassessment tool. We assigned independent samples to IBI development (n = 75) and IBI validation (n = 25) data sets. We placed Hester–Dendy artificial substrates at the sites for 6 wk and processed the samples of colonizing macroinvertebrates in the laboratory with a 500-target subsampling procedure plus a large–rare taxon search. Independent of the biota, we assigned an environmental disturbance...
Abstract: Increasing concerns regarding water quality in the Great Lakes region are mainly due to changes in urban and agricultural landscapes. Both point and non-point sources contribute pollution to Great Lakes surface waters. Best management practices (BMPs) are a common tool used to reduce both point and non-point source pollution and improve water quality. Meanwhile, identification of critical source areas of pollution and placement of BMPs plays an important role in pollution reduction. The goal of this study is to evaluate the performance of different targeting methods in 1) identifying priority areas (high, medium, and low) based on various factors such as pollutant concentration, load, and yield, 2) comparing...