DOI: 10.5194/hess-18-5239-2014
Scopus记录号: 2-s2.0-84918492608
论文题名: Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model
作者: Yeo I ; -Y ; , Lee S ; , Sadeghi A ; M ; , Beeson P ; C ; , Hively W ; D ; , McCarty G ; W ; , Lang M ; W
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2014
卷: 18, 期: 12 起始页码: 5239
结束页码: 5253
语种: 英语
Scopus关键词: Budget control
; Computer simulation
; Crops
; Groundwater
; Leaching
; Nitrates
; Nutrients
; Plants (botany)
; Water quality
; Watersheds
; Agricultural nutrients
; Chesapeake Bay watershed
; Conservation management
; Multitemporal satellites
; Soil and water assessment tool
; Water quality monitoring
; Water quality simulation
; Watershed simulation models
; Loading
; calibration
; cover crop
; environmental economics
; grass
; nitrate
; nutrient uptake
; water budget
; water quality
; watershed
; Chesapeake Bay
; Mid-Atlantic States
; United States
; Secale cereale
; Zea mays
英文摘要: Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay watershed (CBW), which is located in the mid-Atlantic US, winter cover crop use has been emphasized, and federal and state cost-share programs are available to farmers to subsidize the cost of cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops to improve water quality at the watershed scale (∼ 50 km2) and to identify critical source areas of high nitrate export. A physically based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data to simulate hydrological processes and agricultural nutrient cycling over the period of 1990-2000. To accurately simulate winter cover crop biomass in relation to growing conditions, a new approach was developed to further calibrate plant growth parameters that control the leaf area development curve using multitemporal satellite-based measurements of species-specific winter cover crop performance. Multiple SWAT scenarios were developed to obtain baseline information on nitrate loading without winter cover crops and to investigate how nitrate loading could change under different winter cover crop planting scenarios, including different species, planting dates, and implementation areas. The simulation results indicate that winter cover crops have a negligible impact on the water budget but significantly reduce nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading from agricultural lands was approximately 14 kg ha-1, but decreased to 4.6-10.1 kg ha-1 with cover crops resulting in a reduction rate of 27-67% at the watershed scale. Rye was the most effective species, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of cover crops (∼ 30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ∼ 2 kg ha-1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of cover crop implementation. Agricultural fields with well-drained soils and those that were more frequently used to grow corn had a higher potential for nitrate leaching and export to the waterways. This study supports the effective implementation of cover crop programs, in part by helping to target critical pollution source areas for cover crop implementation. © Author(s) 2014. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78037
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Geographical Sciences, University of Maryland, College Park, MD, United States; US Department of Agriculture - Agricultural Research Service, Hydrology and Remote Sensing Laboratory, Beltsville, MD, United States; U.S. Geological Survey, Eastern Geographic Science Center, Reston, VA, United States; School of Engineering, University of Newcastle, Callaghan, NSW, Australia
Recommended Citation:
Yeo I,-Y,, Lee S,et al. Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model[J]. Hydrology and Earth System Sciences,2014-01-01,18(12)