title: Assessment of the Spatial and Temporal Variations of Water Quality for Agricultural Lands with Crop Rotation in China by Using a HYPE Model.
abstract: Many water quality models have been successfully used worldwide to predict nutrient losses from anthropogenically impacted catchments, but hydrological and nutrient simulations with limited data are difficult considering the transfer of model parameters and complication of model calibration and validation. This study aims: (i) to assess the performance capabilities of a new and relatively more advantageous model, namely, Hydrological Predictions for the Environment (HYPE), that simulates stream flow and nutrient load in agricultural areas by using a multi-site and multi-objective parameter calibration method and (ii) to investigate the temporal and spatial variations of total nitrogen (TN) and total phosphorous (TP) concentrations and loads with crop rotation by using the model for the first time. A parameter estimation tool (PEST) was used to calibrate parameters. Results show that the parameters related to the effective soil porosity were highly sensitive to hydrological modeling. N balance was largely controlled by soil denitrification processes. P balance was influenced by the sedimentation rate and production/decay of P in rivers and lakes. The model reproduced the temporal and spatial variations of discharge and TN/TP relatively well in both calibration (2006-2008) and validation (2009-2010) periods. Among the obtained data, the lowest Nash-Suttclife efficiency of discharge, daily TN load, and daily TP load were 0.74, 0.51, and 0.54, respectively. The seasonal variations of daily TN concentrations in the entire simulation period were insufficient, indicated that crop rotation changed the timing and amount of N output. Monthly TN and TP simulation yields revealed that nutrient outputs were abundant in summer in terms of the corresponding discharge. The area-weighted TN and TP load annual yields in five years showed that nutrient loads were extremely high along Hong and Ru rivers, especially in agricultural lands.
authors.affiliation: College of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. 13210740032@fudan.edu.cn.
authors.forename: Yunxing
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Nanjing Institute of Geography and Limnology, Nanjing 210008, China. syjiang@niglas.ac.cn.
authors.forename: Sanyuan
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Swedish Meteorological and Hydrological Institute, Norrkoping SE-601 76, Sweden. Charlotta.Pers@smhi.se.
authors.forename: Charlotta
authors.initials: C
authors.lastname: Pers
authors.affiliation: College of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. xiaoying@fudan.edu.cn.
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Yang
authors.affiliation: Zhumadian City Environmental Protection Bureau, Zhuamadian 463000, China. zmdliuqun@163.com.
authors.forename: Qun
authors.initials: Q
authors.lastname: Liu
authors.affiliation: College of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. 13210740046@fudan.edu.cn.
authors.forename: Jin
authors.initials: J
authors.lastname: Yuan
authors.affiliation: College of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. 13210740033@fudan.edu.cn.
authors.forename: Mingxing
authors.initials: M
authors.lastname: Yao
authors.affiliation: Tyndall Centre for Climate Change Research, School of Environmental Sciences, University of East Anglia, Norwich , Norfolk NR4 7TJ, UK. yi.he@uea.ac.uk.
authors.forename: Yi
authors.initials: Y
authors.lastname: He
authors.affiliation: College of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. lxz@fudan.edu.cn.
authors.forename: Xingzhang
authors.initials: X
authors.lastname: Luo
authors.affiliation: College of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. zzhenghj@fudan.edu.cn.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zheng
mesh_terms: D057914:Agricultural Irrigation / Q000592:standards*; D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D060106:Lakes / Q000737:chemistry*; D008962:Models, Theoretical; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D045483:Rivers / Q000737:chemistry*; D012621:Seasons; D012987:Soil / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D060753:Water Quality / Q000592:standards*
chemical_list: D012987:Soil; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen
keywords: HYPE model; agricultural lands; crop rotation; multi-site and multi-objective calibration; nutrient modeling