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USGS2024

Climate-smart agriculture for Ukraine: Winter wheat breeding for food security and climate adaptation

Since the onset of the COVID-19 pandemic in early 2020, people have experienced food insecurity challenges because of increased prices of staple food commodities and loss of income or livelihood. Globally, countries with limited capacity to adapt have struggled to recover from pandemic-related disruptions and are further challenged to address adverse effects of climate change on agricultural production (United Nations [UN], 2022). Ukraine, a key agricultural exporter of staple food commodities, has a vital role in contributing to global food security, in particular through its wheat exports to countries in the Middle East, North Africa, and Europe (Martyshev and others, 2023). However, Ukraine’s role as a stable source of global wheat has been disrupted by the ongoing Russia-Ukraine war—a conflict which began in February of 2022. Given the fragile state of global and local markets and food systems, and the increasing risk climate change poses to agricultural production globally, Ukraine has prioritized adopting efficient agricultural practices to contribute to stabilizing crop yields and to increase its capacity to export wheat and other staple crops. According to Ukraine’s Ministry of Agrarian Policy and Food (MINAGRO), along with addressing climate change, a contributing driver for this prioritization is the desire to join the European Union (EU) and the need to meet the requirements for the EU’s Common Agricultural Policy (CAP) for acceptance as a union member state (Markiyan Dmytrasevych, a former deputy minister of MINAGRO, oral commun., 2023). As a result, MINAGRO is considering climate-smart agricultural practices to secure future crop yields and build resilience within its agricultural sector, especially as the war has impeded millions of tons of crops from reaching domestic and global markets. This report employs the climate-smart agriculture framework to provide Ukrainian agricultural policy- and decision makers and others in technical and development assistance roles with an overview of relevant climate, environmental, and agricultural policy and market factors, and projections on climate and environmental resources that could influence the implementation of climate-smart agricultural practices in Ukraine, and aid Ukraine in successfully joining the EU.

Report↗
USGS2020

Granular measures of agricultural land use influence lake nitrogen and phosphorus differently at macroscales

Agricultural land use is typically associated with high stream nutrient concentrations and increased nutrient loading to lakes. For lakes, evidence for these associations mostly comes from studies on individual lakes or watersheds that relate concentrations of nitrogen (N) or phosphorus (P) to aggregate measures of agricultural land use, such as the proportion of land used for agriculture in a lake’s watershed. However, at macroscales (i.e., in hundreds to thousands of lakes across large spatial extents), there is high variability around such relationships and it is unclear whether considering more granular (or detailed) agricultural data, such as fertilizer application, planting of specific crops, or the extent of near-stream cropping, would improve prediction and inform understanding of lake nutrient drivers. Furthermore, it is unclear whether lake N and P would have different relationships to such measures and whether these relationships would vary by region, since regional variation has been observed in prior studies using aggregate measures of agriculture. To address these knowledge gaps, we examined relationships between granular measures of agricultural activity and lake total phosphorus (TP) and total nitrogen (TN) concentrations in 928 lakes and their watersheds in the Northeastern and Midwest U.S. using a Bayesian hierarchical modeling approach. We found that both lake TN and TP concentrations were related to these measures of agriculture, especially near-stream agriculture. The relationships between measures of agriculture and lake TN concentrations were more regionally variable than those for TP. Conversely, TP concentrations were more strongly related to lake-specific measures like depth and watershed hydrology relative to TN. Our finding that lake TN and TP concentrations have different relationships with granular measures of agricultural activity has implications for the design of effective and efficient policy approaches to maintain and improve water quality.

Connecticut, Illinois, Indiana, Iowa, Michigan, Mi↗
USGS1995

Indicators of the sources and distribution of nitrate in water from shallow domestic wells in agricultural areas of the New Jersey Coastal Plain

Previously collected and new water-quality data from shallow wells (screened interval less than 30 meters below the land surface) in predominantly agricultural areas of the New Jersey Coastal Plain were used to determine the relation of nitrate concentrations in shallow ground water to various hydrogeologic and land-use factors in the study area. Information on land use, well construction, hydrogeology, and water quality were used to predict the conditions under which concentrations of nitrate as nitrogen in water from domestic wells in predominantly agricultural areas are most likely to be equal to or larger than the U.S. Environmental Protection Agency maximum contaminant level (MCL) of 10 milligrams per liter. Results of the analyses of water-quality samples collected during 1980-89 from 230 shallow wells in the outcrop areas of the Kirkwood-Cohansey and Potomac-Raritan-Magothy aquifer systems were used to evaluate the regional effects of land use on shallow-ground-water quality. Results of statistical analysis indicate that concentrations of nitrate in shallow ground water are significantly different (p= 0.001) in agricultural areas than in undeveloped areas in both aquifer systems. Concentrations of nitrate nitrogen exceeded the MCL in water from more than 33 percent of the 60 shallow wells in agricultural areas. Concentrations of hitrate in water from shallow wells in agricultural areas increased as the percentage of agricultural land within an 800-meter-radius buffer zone of the wellhead increased (r= 0.81). Concentrations ofhitrate in water from domestic wells in agricultural areas were similar (p= 0.23) to those concentrations in water from irrigation wells. These results indicate that most of the nitrate in water from domestic wells in agricultural areas results from agricultural practices rather than other sources, such as septic systems. Water-quality samples collected from 12 shallow domestic wells in agricultural areas screened in the outcrop areas of the Kirkwood-Cohansey and Potomac-Raritan-Magothy aquifer systems were used to evaluate the local effects of hydrogeologic conditions and land-use activities on shallow-ground-water quality. Concentrations of water-quality constituents in these wells were similar among four sampling events over a l-year span. The concentration of hitrate in water from 6 of the 12 wells exceeded the MCL. Concentrations of nitrate greater than the MCL are associated with: values of specific conductance greater than 200 microsiemens per centimeter at 25 degrees Celsius, a screened interval whose top is less than 20 meters below land surface, concentrations of dissolved oxygen greater than 6 milligrams per liter, presence of pesticides in the ground water, a distance of less than 250 meters between the wellhead and the surfacewater divide, and presence of livestock near the wellhead. Ratios of stable isotopes of nitrogen in the water samples indicate that the source of hitrate in the ground water was predominantly chemical fertilizers rather than livestock wastes or effluent from septic systems.

Water-Resources Investigations Report↗
USGS2019

Reducing wet ammonium deposition in Rocky Mountain National Park: The development and evaluation of a pilot early warning system for agricultural operations in eastern Colorado

Agricultural emissions are the primary source of ammonia (NH3) deposition in Rocky Mountain National Park (RMNP), a Class I area, that is granted special air quality protections under the Clean Air Act. Between 2014 and 2016, the pilot phase of the Colorado agricultural nitrogen early warning system (CANEWS) was developed for agricultural producers to voluntarily and temporarily minimize emissions of NH3 during periods of upslope winds. The CANEWS was created using trajectory analyses driven by outputs from an ensemble of numerical weather forecasts together with the climatological expertise of human forecasters. Here, we discuss the methods for the CANEWS and offer preliminary analyses of 33 months of the CANEWS based on atmospheric deposition data from two sites in RMNP as well as responses from agricultural producers after warnings were issued. Results showed that the CANEWS accurately predicted 6 of 9 high N deposition weeks at a lower-elevation observation site, but only 4 of 11 high N deposition weeks at a higher-elevation site. Sixty agricultural producers from 39 of Colorado’s agricultural operations volunteered for the CANEWS, and a two-way line of communication between agricultural producers and scientists was formed. For each warning issued, an average of 23 producers responded to a post-warning survey. Over 75% of responding CANEWS participants altered their practices after an alert. While the current effort was insufficient to reduce atmospheric deposition, we were encouraged by the collaborative spirit between agricultural, scientific, and resource management communities. Solving a broad and complex social-ecological problem requires both a technological approach, such as the CANEWS, and collaboration and trust from all participants, including agricultural producers, land managers, university researchers, and environmental agencies.

Colorado↗
USGS2013

Agricultural sources of contaminants of emerging concern and adverse health effects on freshwater fish

Agricultural contaminants of emerging concern (CECs) are generally thought of as certain classes of chemicals associated with animal feeding and production facilities. Veterinary pharmaceuticals used in animal food production systems represent one of the largest groups of CECs. In our review, we discuss the extensive increase in use of antibiotics in animal feeding operations (AFOs) around the world. AFOs are a major consumer of antibiotics and other veterinary pharmaceuticals and over the past decade there has been growing information on the occurrence, release, and fate of CECs from animal food production operations, including the application of pharmaceutical-containing manure to agricultural fields and releases from waste lagoons. Concentrations of CECs in surface and ground water in proximity to AFOs correspond to their presence in the AFO wastes. In many cases, the environmental concentrations of agriculturally-derived CECs are below toxicity thresholds. Hormones and hormone replacement compounds are a notable exception, where chemical concentrations near AFOs can exceed concentrations known to cause adverse effects on endocrine-related functions in fish. In addition, some agricultural pesticides, once thought to be safe to non-target organisms, have demonstrated endocrine-related effects that may pose threats to fish populations in agricultural regions. That is, we have pesticides with emerging concerns, thus, the concern is emerging and not necessarily the chemical. In this light, one must consider certain agricultural pesticides to be included in the list of CECs. Even though agricultural pesticides are routinely evaluated in regulatory testing schemes which have been used for decades, the potential hazards of some pesticides have only recently been emerging. Emerging concerns of pesticides in fish include interference with hormone signaling pathways; additive (or more than additive) effects from pesticide mixtures; and adverse population-level effects at concentrations below predicted toxicity thresholds. Consequently, there is a need to evaluate the environmental concerns related to pesticide exposures to fish populations based on current biological and toxicological techniques. This presentation reviews some of the agricultural chemicals that have emerged as contaminants of concern and potentially threaten fish populations in agricultural watersheds.

Conference Paper↗
USGS2022

Verification of irrigated agricultural land acreage in 55 counties in Florida, 2013–21

In 2012, the Florida Legislature mandated that the Florida Department of Agriculture and Consumer Services (FDACS), Office of Agricultural Water Policy, promote an agricultural water-conservation program that would include a cost-share program and best management practices and that would aid the five water management districts in the development of consistent agricultural water-supply planning, assisting the districts in projecting future agricultural water needs and promoting consistency in water-use estimates among the districts. Beginning in 2013, the FDACS created a series of agriculture and irrigated land-use maps for all Florida counties for the purpose of estimating current and forecasting future water demands. These maps, produced and updated periodically by The Balmoral Group, were based on baseline data from 2010 and have been updated with a combination of satellite images and land-use data from water management districts in subsequent years (2013–21) to help create a statewide database of irrigated agricultural lands. The purpose of this multiyear cooperative study between the U.S. Geological Survey and the FDACS is to provide (1) a detailed geospatial database of verified irrigated field locations with selected attributes as ArcGIS shapefiles and (2) aggregated acreage totals by crop type for all or parts of 55 of the 67 counties within Florida. Ten of the remaining 12 counties were fully mapped by the St. John’s River Water Management District in 2015; the other 2 counties were not mapped because they contained very little irrigated agricultural land. Irrigated agricultural fields identified on The Balmoral Group baseline maps for each of the 55 counties were either physically observed by U.S. Geological Survey or were verified through water management district’s consumptive water-use permit database. A select group of counties were chosen to be field verified each year, concluding with a total of 55 counties in Florida field verified between October 2013 and August 2021. The results provided from this multiyear study can help increase the accuracy of irrigation water-use estimates for counties in Florida.

Florida↗
USGS1996

Water-quality assessment of the Trinity River Basin, Texas — Pesticides in streams draining an urban and an agricultural area, 1993-95

Water and bed-sediment samples from streams draining an urban and an agricultural area in the Trinity River Basin, Texas, were analyzed. The samples were collected during March 1993?September 1995 by the Trinity River Basin study-unit team of the National Water-Quality Assessment Program. A comparison of pesticide data for water samples from seven streams in the Dallas-Fort Worth urban area with five streams in an agricultural area in the west-central part of the Trinity River Basin showed detections of 24 herbicides in urban-area streams and 19 herbicides in agricultural-area streams and 10 insecticides in each area. Atrazine, a herbicide, was detected in all samples from both areas. Diazinon, an insecticide, was detected in all samples collected in urban-area streams and in about 60 percent of the samples collected in agricultural-area streams. Concentrations of alachlor, atrazine, fluometuron, metolachlor, and pendimethalin (herbicides) were always greater in agricultural-area streams, and prometon and simazine concentrations were always greater in urban-area streams. Atrazine was the only herbicide with concentrations greater than a health advisory limit of 3 micrograms per liter. Concentrations were greater in about 20 percent of the samples; all were in the agricultural area and occurred during spring and during higher streamflow. Diazinon was the only insecticide with concentrations greater than the health advisory of 0.6 microgram per liter. Concentrations were greater in about 15 percent of the samples from the urban area. All exceedances were during spring through early fall and during all ranges of streamflow. In the agricultural area, atrazine and metolachlor concentrations peaked during spring and early summer and increased with increasing streamflow; in the urban area, carbaryl, chlorpyrifos, and diazinon peaked in April and remained relatively high during the summer and increased with increasing streamflow. A comparison of pesticide data for bed-sediment samples from five urban streams and five agricultural streams showed detections of 11 organochlorine insecticides in the urban area and 1 in the agricultural area. All compounds were either DDT-related or one of the components of chlordane except for mirex and dieldrin.

Texas↗
USGS1998

Pesticides in storm runoff from agricultural and urban areas in the Tuolumne River basin in the vicinity of Modesto, California

The occurrence, concentrations, and loads of dissolved pesticides in storm runoff were compared for two contrasting land uses in the Tuolumne River Basin, California, during two different winter storms: agricultural areas (February 1994) and the Modesto urban area (February 1995). Both storms followed the main application period of pesticides on dormant almond orchards. Eight samples of runoff from agricultural areas were collected from a Tuolumne River site, and 10 samples of runoff from urban areas were collected from five storm drains. All samples were analyzed for 46 pesticides. Six pesticides were detected in runoff from agricultural areas, and 15 pesticides were detected in runoff from urban areas. Chlorpyrifos, diazinon, dacthal (DCPA), metolachlor, and simazine were detected in almost every sample. Median concentrations were higher in the runoff from urban areas for all pesticides except napropamide and simazine. The greater occurrence and concentrations in storm drains is partly attributed to dilution of agricultural runoff by nonstorm base-flow in the Tuolumne River and by storm runoff from nonagricultural and nonurban land. In most cases, the occurrence and relative concentrations of pesticides found in storm runoff from agricultural and urban areas were related to reported pesticide application. Pesticide concentrations in runoff from agricultural areas were more variable during the storm hydrograph than were concentrations in runoff from urban areas. All peak pesticide concentrations in runoff from agricultural areas occurred during the rising limb of the storm hydrograph, whereas peak concentrations in the storm drains occurred at varying times during the storm hydrograph. Transport of pesticides from agricultural areas during the February 1994 storm exceeded transport from urban areas during the February 1995 storm for chlorpyrifos, diazinon, metolachlor, napropamide, and simazine. Transport of DCPA was about the same from agricultural and urban sources, and the main source of transport for the other pesticides could not be determined because of concentrations less than the method detection limit.

Water-Resources Investigations Report↗
USGS2012

Exploring relationships among land ownership, agricultural land use, and native fish species richness in the Upper Mississippi River Basin

The general effects of agriculture on in-stream fish communities in the Upper Midwestern United States have been well studied for nearly three decades (Karr et al. 1985; Nerbonne and Vondracek 1991; Zimmerman et al. 2001; Goldstein and Meador 2005). Specific impacts include: lowered water levels, sediment loading and nutrient enrichment, loss of riparian habitat, changes to channel morphometry and physical habitat, and changes to the forage base. As part of the National Fish Habitat Action Plan (NFHAP), an initiative to protect, restore, and enhance the nation's fish and aquatic communities, the Fishers and Farmers Partnership specifically focuses on working with agricultural producers to help protect and restore aquatic resources in the Upper Mississippi River Basin (UMRB) (Fig. 1). Successful protection and/or restoration will require the partnership and local conservation agencies to effectively communicate and work with local landowners. However, roughly 43% of the agricultural lands in the UMRB are not operated by those who own the land (National Agricultural Statistics Service 2009) and this is expected to increase as heirs of farm estates now reside greater distances from their home farms than ever before (Arbuckle 2010). It has long been presumed that changes in land ownership trends, toward more absentee landowners, would have important consequences for soil erosion and other conservation practices, as larger, more corporate agriculture, is thought to maximize farm income at the expense of environmental quality (Lee 1980). Absentee landowners may be less likely to take advantage of conservation programs. For example, land operated by renters lags enrollment in the Conservation Reserve (CRP) and Wetland Reserve (WRP) programs by 64% nation-wide (Petrzelka et al. 2009). Also, it has been found that the more detached an absentee landowner becomes from their land, both geographically and culturally, their commitment to land stewardship decreases (Arbuckle 2010). The Fishers and Farmers Partnership recognizes the challenge agricultural producers face in maintaining food and fiber production for a growing world population while also trying to improve environmental quality and fish habitat. This challenge is likely exacerbated when the landowners are absentee. Thus, reaching non-owner-operated farmers and convincing them to help protect and/or restore aquatic resources may be critical to the success of the Fishers and Farmers Partnership. In this study, we explored relationships among agricultural land use, land ownership, and native fish biodiversity in the UMRB as a first step toward helping the Fishers and Farmers Partnership identify specific locations in the UMRB that may pose conservation challenges. For example, places that have experienced a loss of native fish species richness relative to historical conditions and also have high proportions of absentee landowners may provide restoration challenges. We were also interested in identifying areas that have retained high levels of species richness and are owner-operated. These areas present good opportunities to work with local landowners to protect aquatic resources. To identify such areas, we addressed two primary questions: 1) Is there a relationship between the type of agricultural land use (i.e. cropland vs pastureland) and the % of land rented or leased within the UMRB? and 2) How does the type of agricultural production and whether land is rented or leased relate to the maintenance of historical levels of native fish species richness? We predicted that areas with large amounts of land devoted to crop production will have experienced the greatest losses of native fish species richness. However, our hypothesis is that watersheds with large amounts of land rented or leased will have experienced even greater declines in native fish species richness than would be predicted from the amount of cultivated cropland alone. By testing these hypotheses, we intended to identify watersheds that would be strong candidates for protection, restoration, and enhancement of fish species richness by accounting for land use and ownership characteristics.

Illinois, Indiana, Iowa, Michigan, Minnesota, Miss↗
USGS2013

The role of irrigation runoff and winter rainfall on dissolved organic carbon loads in an agricultural watershed

We investigated the role of land use/land cover and agriculture practices on stream dissolved organic carbon (DOC) dynamics in the Willow Slough watershed (WSW) from 2006 to 2008. The 415 km 2 watershed in the northern Central Valley, California is covered by 31% of native vegetation and the remaining 69% of agricultural fields (primarily alfalfa, tomatoes, and rice). Stream discharge and weekly DOC concentrations were measured at eight nested subwatersheds to estimate the DOC loads and yields (loads/area) using the USGS developed stream load estimation model, LOADEST. Stream DOC concentrations peaked at 18.9 mg L −1 during summer irrigation in the subwatershed with the highest percentage of agricultural land use, demonstrating the strong influence of agricultural activities on summer DOC dynamics. These high concentrations contributed to DOC yields increasing up to 1.29 g m −2 during the 6 month period of intensive agricultural activity. The high DOC yields from the most agricultural subwatershed during the summer irrigation period was similar throughout the study, suggesting that summer DOC loads from irrigation runoff would not change significantly in the absence of major changes in crops or irrigation practices. In contrast, annual DOC yields varied from 0.89 to 1.68 g m −2 yr −1 for the most agricultural watershed due to differences in winter precipitation. This suggests that variability in the annual DOC yields will be largely determined by the winter precipitation, which can vary significantly from year to year. Changes in precipitation patterns and intensities as well as agricultural practices have potential to considerably alter the DOC dynamics.

California↗
USGS2010

Introduction to the JEEG Agricultural Geophysics Special Issue

Near-surface geophysical methods have become increasingly important tools in applied agricultural practices and studies. The great advantage of geophysical methods is their potential rapidity, low cost, and spatial continuity when compared to more traditional methods of assessing agricultural land, such as sample collection and laboratory analysis. Agricultural geophysics investigations commonly focus on obtaining information within the soil profile, which generally does not extend much beyond 2 meters beneath the ground surface. Although the depth of interest oftentimes is rather shallow, the area covered by an agricultural geophysics survey can vary widely in scale, from experimental plots (10 s to 100 s of square meters), to farm fields (10 s to 100 s of hectares), up to the size of watersheds (10 s to 100 s of square kilometers). To date, three predominant methods—resistivity, electromagnetic induction (EMI), and ground-penetrating radar (GPR)—have been used to obtain surface-based geophysical measurements within agricultural settings. However, a recent conference on agricultural geophysics (Bouyoucos Conference on Agricultural Geophysics, September 8–10, 2009, Albuquerque, New Mexico; www.ag-geophysics.org) illustrated that other geophysical methods are being applied or developed. These include airborne electromagnetic induction, magnetometry, seismic, and self-potential methods. Agricultural geophysical studies are also being linked to ground water studies that utilize deeper penetrating geophysical methods than normally used.

Journal of Environmental & Engineering Geophysics↗
USGS2015

Preliminary estimates of annual agricultural pesticide use for counties of the conterminous United States, 2013

Summary This report provides preliminary estimates of annual agricultural use of 387 pesticide compounds in counties of the conterminous United States in 2013, compiled by means of methods described in Thelin and Stone (2013) and Baker and Stone (2015). U.S. Department of Agriculture county-level data for harvested-crop acreage were used in conjunction with proprietary Crop Reporting District-level pesticide-use data to estimate county-level pesticide use. Where Crop Reporting District data were not available or were incomplete, estimated pesticide use values were calculated with two different methods, resulting in a low and a high estimate based on different assumptions about missing survey data (Thelin and Stone, 2013). Preliminary estimates in this report are expected to be revised upon availability of updated crop acreages in the 2017 Agricultural Census, to be published by the U.S. Department of Agriculture in 2019. Estimates of annual agricultural pesticide use are provided as downloadable, tab-delimited files, which are organized by compound, year, state Federal Information Processing Standard (FIPS) code, county Federal Information Processing Standard code, and amount in kilograms (kg). The files, listed below, are a continuation of the 1992–2009 and 2008–2012 pesticide-use estimates reported by Stone (2013) and Baker and Stone (2015), respectively: High estimates of county pesticide use, arranged by pesticide name: Table 1. 1-Methyl Cyclopropene through Chlorantraniliprole Table 2. Chlorethoxyfos through Diflufenzopyr Table 3. Dimethenamid through Gibberellic Acid Table 4. Glufosinate through Metiram Table 5. Metolachlor through Propazine Table 6. Propiconazole through Triasulfuron Table 7. Tribenuron Methyl through Zoxamide Low estimates of county pesticide use, arranged by pesticide name: Table 8. 1-Methyl Cyclopropene through Chlorantraniliprole Table 9. Chlorethoxyfos through Diflufenzopyr Table 10. Dimethenamid through Gibberellic Acid Table 11. Glufosinate through Metiram Table 12. Metolachlor through Propazine Table 13. Propiconazole through Triasulfuron Table 14. Tribenuron Methyl through Zoxamide References Cited Baker, N.T., and Stone, W.W., 2015, Estimated annual agricultural pesticide use for counties of the conterminous United States, 2008–12: U.S. Geological Survey Data Series 907, 9 p., accessed July, 12, 2015, at http://dx.doi.org/10.3133/ds907. Stone, W.W., 2013, Estimated annual agricultural pesticide use for counties of the conterminous United States, 1992–2009: U.S. Geological Survey Data Series 752, 1 p., 14 tables Thelin, G.P., and Stone, W.W., 2013, Estimation of annual agricultural pesticide use for counties of the conterminous United States, 1992–2009: U.S. Geological Survey Scientific Investigations Report 2013–5009, 54 p.

Open-File Report↗
USGS2014

Development of a regionally consistent geospatial dataset of agricultural lands in the Upper Colorado River Basin, 2007-10

Irrigation in arid environments can alter the natural rate at which salts are dissolved and transported to streams. Irrigated agricultural lands are the major anthropogenic source of dissolved solids in the Upper Colorado River Basin (UCRB). Understanding the location, spatial distribution, and irrigation status of agricultural lands and the method used to deliver water to agricultural lands are important to help improve the understanding of agriculturally derived dissolved-solids loading to surface water in the UCRB. Irrigation status is the presence or absence of irrigation on an agricultural field during the selected growing season or seasons. Irrigation method is the system used to irrigate a field. Irrigation method can broadly be grouped into sprinkler or flood methods, although other techniques such as drip irrigation are used in the UCRB. Flood irrigation generally causes greater dissolved-solids loading to streams than sprinkler irrigation. Agricultural lands in the UCRB mapped by state agencies at varying spatial and temporal resolutions were assembled and edited to represent conditions in the UCRB between 2007 and 2010. Edits were based on examination of 1-meter resolution aerial imagery collected between 2009 and 2011. Remote sensing classification techniques were used to classify irrigation status for the June to September growing seasons between 2007 and 2010. The final dataset contains polygons representing approximately 1,759,900 acres of agricultural lands in the UCRB. Approximately 66 percent of the mapped agricultural lands were likely irrigated during the study period.

Arizona, Colorado, New Mexico, Utah, Wyoming↗
USGS2003

Ground-water quality beneath irrigated agriculture in the central High Plains aquifer, 1999-2000

In 1999 and 2000, 30 water-quality monitoring wells were installed in the central High Plains aquifer to evaluate the quality of recently recharged ground water in areas of irrigated agriculture and to identify the factors affecting ground-water quality. Wells were installed adjacent to irrigated agricultural fields with 10- or 20-foot screened intervals placed near the water table. Each well was sampled once for about 100 waterquality constituents associated with agricultural practices. Water samples from 70 percent of the wells (21 of 30 sites) contained nitrate concentrations larger than expected background concentrations (about 3 mg/L as N) and detectable pesticides. Atrazine or its metabolite, deethylatrazine, were detected with greater frequency than other pesticides and were present in all 21 samples where pesticides were detected. The 21 samples with detectable pesticides also contained tritium concentrations large enough to indicate that at least some part of the water sample had been recharged within about the last 50 years. These 21 ground-water samples are considered to show water-quality effects related to irrigated agriculture. The remaining 9 groundwater samples contained no pesticides, small tritium concentrations, and nitrate concentrations less than 3.45 milligrams per liter as nitrogen. These samples are considered unaffected by the irrigated agricultural land-use setting. Nitrogen isotope ratios indicate that commercial fertilizer was the dominant source of nitrate in 13 of the 21 samples affected by irrigated agriculture. Nitrogen isotope ratios for 4 of these 21 samples were indicative of an animal waste source. Dissolved-solids concentrations were larger in samples affected by irrigated agriculture, with large sulfate concentrations having strong correlation with large dissolved solids concentrations in these samples. A strong statistical correlation is shown between samples affected by irrigated agriculture and sites with large rates of pesticide and nitrogen applications and shallow depths to ground water.

Water-Resources Investigations Report↗
USGS1995

Agricultural pesticide applications and observed concentrations in surface waters from four drainage basins in the Central Columbia Plateau, Washington and Idaho, 1993-94

As part of the U.S. Geological Survey's National Water-Quality Assessment Program, the use and occurrence of agricultural pesticides were investigated in four drainage basins--two dominated by irrigated agriculture and two by dryland agriculture--in the Central Columbia Plateau of eastern Washington. For this study, 85 pesticides or pesticide metabolites were selected for analysis from a list of nearly 400 compounds commonly used in the United States. Pesticide-use data included estimates of the total quantity of herbicides, insecticides, and fungicides applied to croplands in each of the four drainage basins and reported times of application for selected pesticides. Pesticide-occurrence data included concentrations of pesticides in samples collected at one surface-water site at or near the outflow of each of the four drainage basins, where surface waters were sampled one to five times a month from March 1993 through May 1994. Of the 85 pesticides or pesticide metabolites targeted for analysis, a total of 45 different compounds were detected in samples from the four sites, ranging in concentration from at or near the limit of detection (as low as 0.001 microgram per liter) to a maximum of 8.1 micrograms per liter. None of the concentrations of pesticides exceeded the U.S. Environmental Protection Agency (USEPA) drinking water standards, but concentrations of five pesticides exceeded the USEPA freshwater-chronic criteria for the protection of aquatic life. Forty-one different pesticides or pesticide metabolites were detected in surface waters sampled at the two sites representing irrigated agriculture drainage basins. The herbicides atrazine, DCPA, and EPTC were detected most frequently at the two sampling sites. Not all pesticides that were applied were detected, however. For example, disulfoton, phorate, and methyl parathion accounted for 15 percent of the insecticides applied in the two irrigated drainage basins, yet none of these pesticides were detected in samples from the two irrigated-agricultural sites. Concentrations of pesticides found in surface waters at the two sites representing irrigated agriculture did not exceed drinking water standards, but some concentrations of the insecticides carbaryl, chlorpyrifos, diazinon, and azinphos-methyl exceeded the freshwater-chronic criteria for the protection of aquatic life. Twenty-three different pesticides or pesticide metabolites were detected in samples from the two sites representing dryland agricultural drainage basins. Herbicides were the type of pesticides most heavily applied in these drainage basins, and the herbicides atrazine, triallate, and simazine were detected most frequently in samples. Some herbicides, for example triallate in the Palouse River drainage basin, were both heavily applied and frequently detected. Others, like atrazine and simazine, were not typically applied to cropland, but were frequently detected in surface-water samples. Several insecticides (Lindane, ethoprop, carbaryl, and azinphos-methyl) were detected in samples from the two sites, although they were not reported as commonly applied to croplands in the dryland agricultural drainage basins. Concentrations of pesticides found in surface waters at the two sites did not exceed drinking water guidelines, but concentrations of the insecticides diazinon and azinphos-methyl and the herbicide triallate exceeded freshwater-chronic criteria for the protection of aquatic life.

Water-Resources Investigations Report↗
USGS1996

Benthic invertebrates of benchmark streams in agricultural areas of eastern Wisconsin — Western Lake Michigan drainages

This study describes the benthic invertebrate communities of 20 benchmark streams in agricultural areas of eastern Wisconsin. Streams with minimal adverse effects from human activity were selected from four agricultural areas with differing surficial deposits and bedrock types (relatively homogeneous units, or RHU's). Most aquatic invertebrate orders were well represented in the 20 benchmark stream samples; 217 species and 151 genera within 56 families were identified. Diptera was the best represented order (96 species), followed by Trichoptera (42 species) and Ephemeroptera (26 species). Diptera were the most abundant organisms in terms of numbers of individuals in the sample (28 percent of the total) followed by Trichoptera (25 percent) and Ephemeroptera (13 percent). Nine species of freshwater mussels were found, but only in 5 of the 20 benchmark streams. Community measures were calculated for the following: total number of individuals; number of species; number of families; Margalef's diversity index; percent dominant family; percent Ephemeroptera-Plecoptera-Trichoptera (EPT); ratio of EPT to Chironomidae; percent shredders; ratio of scrapers to collectors-gatherers-filterers; Hilsenhoff's Biotic Index; Hilsenhoff's family level biotic index; and mean tolerance value. The S AS statistical software package was used for calculations of variance and correlations, normality checks, and principal components analysis of these measures and to find relations between benthic-invertebrate data and environmental-setting, habitat, and water-quality data. Coefficients of variation within the RHU's were as great or greater than those for all 20 streams for most measures and RHU's. The specific taxa assemblages present at the sites did not show distinct differences between RHU's or similarities within the RHU's. The covariance and the Kruskal-Wallis tests showed that the benthic invertebrate measures were not related to RHU. These results all indicate that the combined effect of the RHU variables (bedrock geology, texture of surficial deposits, and land use/land cover) were not elemental in describing invertebrate communities in the study-area streams. A principal components analysis (PCA) was done on the 20 benchmark streams which used the invertebrate population measures as variables. A three-dimensional ordination plot of these components revealed that 18 of the 20 streams could be divided into three groups relative to stream size, available habitat, and water quality. The three classifications of streams include large, warmer streams with slight pollution; deep, mixed-water streams with minimal pollution; and small, cold, pristine headwater streams. The two streams not defined by the three PCA groupings were not suitable to represent benchmark conditions. One site lacked suitable quality habitat or sufficient nutrients to support a healthy population of invertebrates, causing low measures of diversity. The other site appeared to be affected by sedimentation and low flows. The classification groupings did not show any significant relations to percentage agricultural land use. Percentage of agricultural land use varied greatly within each group and the means for each group were similar. All streams in this study had some level of protection from agricultural practices in their basins. Although the intensity of agriculture is known to be a factor causing deterioration of invertebrate populations in past studies, the finding in this study indicated that the level of protection the stream received and other factors such as environmental setting and habitat could be more important to benthic invertebrates than the percentage of agriculture in the basin. Information gathered from these benchmark streams can be used as a regional reference for comparison with other streams in agricultural areas, based on communities of aquatic biota, habitat, and water quality.

Wisconsin↗
USGS2019

Multipurpose oxbows as a nitrate export reduction practice in the agricultural Midwest

Core Ideas Oxbows reduce nitrate export from agricultural fields to adjacent rivers and streams. Oxbows are important habitat for wildlife, including the endangered Topeka shiner. Oxbows have largely disappeared from midwestern landscapes modified for agriculture. Restoring multipurpose oxbows provides multiple benefits in the agricultural Midwest. Nutrient export from the agricultural US Midwest influences streams and rivers and contributes to the development of hypoxia in the Gulf of Mexico. Oxbows are natural waterbodies formed when a river cuts off a meander loop as it migrates within its floodplain. Creation of multipurpose oxbows by restoration of former oxbows can potentially reduce export of nitrate-nitrogen (nitrate) from agricultural land as well as provide important habitat for many species, including the endangered Topeka shiner. Recent studies of nitrate export reduction by oxbows in Iowa are encouraging, demonstrating a 45% reduction in nitrate export of water entering oxbows from subsurface tiles compared with water discharged to the adjacent stream. Oxbow restorations are as effective as several other nutrient reduction practices, are relatively inexpensive, last for decades if not centuries, remove little or no land from agricultural production, and provide significant ecosystem services. Multipurpose oxbows are a promising new best management practice for reducing nitrate export from agricultural lands.

Iowa↗
USGS2016

Managing adaptively for multifunctionality in agricultural systems

The critical importance of agricultural systems for food security and as a dominant global landcover requires management that considers the full dimensions of system functions at appropriate scales, i.e. multifunctionality. We propose that adaptive management is the most suitable management approach for such goals, given its ability to reduce uncertainty over time and support multiple objectives within a system, for multiple actors. As such, adaptive management may be the most appropriate method for sustainably intensifying production whilst increasing the quantity and quality of ecosystem services. However, the current assessment of performance of agricultural systems doesn’t reward ecosystem service provision. Therefore, we present an overview of the ecosystem functions agricultural systems should and could provide, coupled with a revised definition for assessing the performance of agricultural systems from a multifunctional perspective that, when all satisfied, would create adaptive agricultural systems that can increase production whilst ensuring food security and the quantity and quality of ecosystem services. The outcome of this high level of performance is the capacity to respond to multiple shocks without collapse, equity and triple bottom line sustainability. Through the assessment of case studies, we find that alternatives to industrialized agricultural systems incorporate more functional goals, but that there are mixed findings as to whether these goals translate into positive measurable outcomes. We suggest that an adaptive management perspective would support the implementation of a systematic analysis of the social, ecological and economic trade-offs occurring within such systems, particularly between ecosystem services and functions, in order to provide suitable and comparable assessments. We also identify indicators to monitor performance at multiple scales in agricultural systems which can be used within an adaptive management framework to increase resilience at multiple scales.

Journal of Environmental Management↗