Abstract:
:Protection of ground water for present and future use requires monitoring and understanding of the mechanisms controlling long-term quality of ground water. In this study, spatial and temporal trends in concentrations of nitrate and pesticides in ground water in the eastern San Joaquin Valley, California, were evaluated to determine the long-term effects of agricultural and urban development on regional ground-water quality. Trends in concentrations of nitrate, the nematocide 1,2-dibromo-3-chloropropane, and the herbicide simazine during the last two decades are generally consistent with known nitrogen fertilizer and pesticide use and with the position of the well networks in the regional ground-water flow system. Concentrations of nitrate and pesticides are higher in the shallow part of the aquifer system where domestic wells are typically screened, whereas concentrations are lower in the deep part of the aquifer system where public-supply wells are typically screened. Attenuation processes do not seem to significantly affect concentrations. Historical data indicate that concentrations of nitrate have increased since the 1950s in the shallow and deep parts of the aquifer system. Concentrations of nitrate and detection of pesticides in the deep part of the aquifer system will likely increase as the proportion of highly affected water contributed to these wells increases with time. Because of the time of travel between the water table and the deep part of the aquifer system, current concentrations in public-supply wells likely reflect the effects of 40- to 50-yr-old management practices.
journal_name
J Environ Qualjournal_title
Journal of environmental qualityauthors
Burow KR,Shelton JL,Dubrovsky NMdoi
10.2134/jeq2007.0061subject
Has Abstractpub_date
2008-09-01 00:00:00pages
S249-63issue
5 Suppleissn
0047-2425issn
1537-2537pii
37/5_Supplement/S-249journal_volume
37pub_type
杂志文章abstract::Interest in the use of biochar from pyrolysis of biomass to sequester C and improve soil productivity has increased; however, variability in physical and chemical characteristics raises concerns about effects on soil processes. Of particular concern is the effect of biochar on soil N dynamics. The effect of biochar on...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2011.0133
更新日期:2012-07-01 00:00:00
abstract::Beef cattle feedlots emit large amounts of the greenhouse gases (GHG) methane (CH) and nitrous oxide (NO), as well as ammonia (NH), which contributes to NO emission when NH is deposited to land. However, there is a lack of simultaneous, in situ, and nondisturbed measurements of the major GHG gas components from beef c...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2015.06.0278
更新日期:2015-11-01 00:00:00
abstract::In this study, we develop and apply a methodology to reduce an existing monitoring network to find an optimal configuration of a smaller network. We use a criterion based on locally weighted regression with two different weight functions. The methodology is applied to the Dutch national SO2 network and offers the poss...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2002.1210
更新日期:2002-01-01 00:00:00
abstract::To control ammonia (NH(3)) volatilization from the dairy cattle (Bos taurus) manure composting process, a compost pile was covered with mature compost and the gas emissions evaluated using the dynamic chamber system. The peak of NH(3) volatilization observed immediately after piling up of the compost was reduced from ...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2008.0083
更新日期:2009-02-06 00:00:00
abstract::The effectiveness of various management practices to reduce phosphorus (P) loss from soil to water can potentially be improved by using by-product materials that have the capacity to sorb phosphorus. This study evaluated the P sorption and desorption potential, and the physicochemical characteristics of various phosph...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2007.0148
更新日期:2008-01-04 00:00:00
abstract::Determination of sorption of hydrophilic, weakly sorbing organic compounds in soil by conventional batch methods using a slurried suspension is often prone to considerable errors because small changes in the solution concentration on equilibration must be accurately determined. This difficulty is exacerbated for compo...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2003.0423
更新日期:2005-05-11 00:00:00
abstract::Phosphorus is among the essential nutrients applied to sugarcane ( L.) fields in the form of a fertilizer mixture (N, P, and K) in southwestern Florida. Sorption coefficient is used for modeling P movement, and in this study, we hypothesized that the sorption coefficient determined using fertilizer mixture (N, P, and ...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2016.03.0087
更新日期:2016-09-01 00:00:00
abstract::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 Io...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2009.0392
更新日期:2010-07-01 00:00:00
abstract::The pH value of poultry litter is affected by nitrification, mineralization, and the addition of acidifying chemicals, all acting on the poultry litter pH buffering capacity (pHBC). Increased understanding of poultry litter pHBC will aid in modeling NH volatilization from surface-applied poultry litter as well as esti...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2014.11.0463
更新日期:2015-07-01 00:00:00
abstract::Horse paddocks have been identified as a significant contributor of animal waste nutrients to natural waters; thus, modified paddock management is needed. Because chemical amendments pose a health risk to horses, an alternative for reducing nutrient translocation from manure is to add available organic residues to the...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2016.06.0223
更新日期:2017-01-01 00:00:00
abstract::During recent decades, a change in land use in the mountainous regions of Northern Thailand has been accompanied by an increased input of agrochemicals. We identified lateral water flow and pesticide transport pathways and mechanisms in a Hapludult on a sloped litchi orchard in Northern Thailand. During two rainy seas...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2006.0241
更新日期:2007-06-27 00:00:00
abstract::Control methods are needed to abate NH losses from swine anaerobic lagoons to reduce the contribution of confined swine operations to air pollution. In a 15-mo meso-scale column study, we evaluated the effect of manure pretreatment on water quality, reduction of N losses, and sludge accumulation in swine lagoons using...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2013.08.0330
更新日期:2014-07-01 00:00:00
abstract::Scaling in situ soil water content time series data to a large spatial domain is a key element of watershed environmental monitoring and modeling. The primary method of estimating and monitoring large-scale soil water content distributions is via in situ networks. It is critical to establish the stability of in situ n...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2013.08.0318
更新日期:2014-07-01 00:00:00
abstract::Excess NO leaching from the agricultural Midwest via tile drainage water has contributed to both local drinking water and national Gulf of Mexico benthic hypoxia concerns. Both in-field and edge-of-field practices have been designed to help mitigate NO flux to surface waters. Edge-of-field practices focus on maximizin...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2018.03.0125
更新日期:2019-03-01 00:00:00
abstract::The groundwater of Jeju Island (Republic of Korea) is vulnerable to contamination because its aquifers are mainly composed of highly permeable geological units and its agricultural fields are often exposed to excessive use of predominantly synthetic fertilizers. In the Gosan area of Jeju Island, we investigated nitrat...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2011.0417
更新日期:2012-11-01 00:00:00
abstract::Conservation tillage practices have become increasingly common in recent years to reduce soil erosion, improve water conservation, and increase soil organic matter. Research suggests that conservation tillage can stratify soil test phosphorus (P), but little is known about the effects on soil organic P. This study was...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2013.10.0424
更新日期:2014-07-01 00:00:00
abstract::Influence of soil properties and aging on Cu partitioning and toxicity was assessed on 10 artificial soils constituted using a statistical design considering pH (5.5 and 7.5), organic matter (1-30% [w/w]), and clay content (5-35% [w/w]). Total Cu as well as water-, CaCl2-, and diethylene triamine pentaacetic acid (DTP...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2005.0107
更新日期:2006-03-01 00:00:00
abstract::Chloride is a relatively unreactive plant nutrient that has long been used as a biogeochemical tracer but also can be a pollutant causing aquatic biology impacts when concentrations are high, typically from rock salt applications used for deicing roads. Chloride inputs to watersheds are most often from atmospheric dep...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2015.06.0302
更新日期:2016-01-01 00:00:00
abstract::There are few beneficial management practices (BMPs) with demonstrated efficacy in snowmelt-dominated regions. Small reservoirs are a BMP that can help mitigate flooding and reduce sediment transport, while reducing export of dissolved nutrients. To understand controls on nitrate removal and assess how this ecosystem ...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2016.07.0252
更新日期:2017-01-01 00:00:00
abstract::Agriculture in the midwestern United States is a major anthropogenic source of nitrous oxide (NO) and is both a source and sink for methane (CH), but the degree to which cropping systems differ in emissions of these gases is not well understood. Our objectives were to determine if fluxes of NO and CH varied among crop...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2014.02.0077
更新日期:2014-11-01 00:00:00
abstract::Concentrated animal feeding operations emit trace gases such as ammonia (NH₃), methane (CH₄), carbon dioxide (CO₂), and nitrous oxide (N₂O). The implementation of air quality regulations in livestock-producing states increases the need for accurate on-farm determination of emission rates. The objective of this study w...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2009.0515
更新日期:2011-09-01 00:00:00
abstract::Soils support ecosystem functions such as plant growth and water quality because of certain physical, chemical, and biological properties. These properties have been studied at different spatial scales, including point scales to satisfy basic research needs, and regional scales to satisfy monitoring needs. Recently, s...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2001.301101x
更新日期:2001-01-01 00:00:00
abstract::Macropores formed by roots are crucial channels for preferential flows in forest soils that are largely responsible for water percolation and solute leaching. Using dual-tracer experiments (Brilliant Blue FCF and bromide [Br]), this study investigated the preferential flows of water and solutes in a deciduous forest d...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2018.03.0091
更新日期:2019-01-01 00:00:00
abstract::Poultry litter (PL) is a by-product of broiler production. Most PL is land applied. Land-applied PL is a valuable nutrient source for crop production but can also be a route of environmental contamination with manure-borne bacteria. The objective of this study was to characterize the fate of pathogens, fecal indicator...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2013.10.0432
更新日期:2014-09-01 00:00:00
abstract::Complex variation in gas emissions from animal facilities has been shown in recent research reports. Uncertainties in these emission estimates are driving research activities concerning different animal species across the globe. Greenhouse gas (NO and CO) and NH concentrations were measured in a modern, tunnel-ventila...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2013.09.0390
更新日期:2014-07-01 00:00:00
abstract::Farmed landscapes are engineered for productivity, and research suggests they contribute a disproportionate share of inorganic C to the Mississippi River and Gulf of Mexico. Here we use alkalinity and total organic C (TOC) measurements collected from the Raccoon River of Iowa to (i) evaluate inorganic and organic C co...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2012.0159
更新日期:2013-01-01 00:00:00
abstract::Phosphorous (P) and nitrogen (N) in runoff from agricultural fields are key components of nonpoint-source pollution and can accelerate eutrophication of surface waters. A laboratory study was designed to evaluate effects of near-surface hydraulic gradients on P and N losses in surface runoff from soil pans at 5% slope...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2004.2174
更新日期:2004-11-01 00:00:00
abstract::Perchlorate (ClO4-) contamination of ground water and surface water is a widespread problem, particularly in the western United States. This study examined the effect of biodegradation on perchlorate fate and transport in soils. Solute transport experiments were conducted on two surface soils. Pulses of solution conta...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2003.4000
更新日期:2003-01-01 00:00:00
abstract::Restored riparian wetlands in the Upper Mississippi River basin have potential to remove sediment and nutrients from tributaries before they flow into the Mississippi River. For 3 yr we calculated retention efficiencies of a marsh complex, which consisted of a restored marsh and an adjacent natural marsh that were con...
journal_title:Journal of environmental quality
pub_type: 杂志文章
doi:10.2134/jeq2012.0248
更新日期:2013-03-01 00:00:00
abstract::The influence of zoonotic pathogens in animal manure on human health and well-being as a direct or indirect cause of human enteric illness is examined. Available international data are considered, but the study is focused on the developing situation in western Canada, where it is certain there will be further rapid gr...
journal_title:Journal of environmental quality
pub_type: 杂志文章,评审
doi:10.2134/jeq2003.3830
更新日期:2003-03-01 00:00:00