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Journal of Environmental Sciences 2010年第6期22卷 826-833页

作者： MiSeon Lee GeunAe Park MinJi Park JongYoon Park JiWan Lee SeongJoon Kim Department of Rural Engineering Konkuk University Department of Civil and Environmental System Engineering Konkuk University

This study evaluated the reduction effect of non-point source pollution by applying best management practices （BMPs） to a 1.21 km^2 small agricultural watershed using a SWAT （Soil and Water Assessment Tool） model. Two meter QuickBird land use data were prepared for the watershed. The SWAT was calibrated and validated using dally streamflow and monthly water quality （total phosphorus （TP）, total nitrogen （TN）, and suspended solids （SS）） records from 1999 to 2000 and from 2001 to 2002. The average Nash and Sutcliffe model efficiency was 0.63 for the streamflow and the coefficients of determination were 0.88, 0.72, and 0.68 for SS, TN, and TP, respectively. Four BMP scenarios viz. the application of vegetation filter strip and riparian buffer system, the regulation of Universal Soil Loss Equation P factor, and the fertilizing control amount for crops were applied and analyzed.

关键词： QuickBird land use Soil and Water Assessment Tool best management practice non-point source

Monitoring of non-point source pollutants load from a mixed forest land use

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Journal of Environmental Sciences 2010年第6期22卷 801-805页

作者： Sung Wan Yoon Se Woong Chung Dong Geun Oh Jae Woon Lee Department of Environmental Engineering Chungbuk National University Geum River Environmental Research Center National Institute of Environmental Research

The aim of this study was to determine the unit load of NPS （non-point source） pollutants including organic variables such as BOD （biochemical oxygen demand）, COD （chemical oxygen demand） and DOC （dissolved organic carbon）, nitrogen and phosphorus constituents, and suspended solids （SS） and their event mean concentration （EMC） of runoff flows from a water-shed of mixed forest land use by intensive field experiments. Field monitoring for continuous measurements of rainfall, flow, and water quality was conducted over 12 storm events during 2008-2009 using automated and manual sampling methods. The EMCs of individual runoff event were estimated for each water quality constituent based on the flow rate and concentration data of runoff discharge. The average EMCs of BOD, COD, DOC, SS, TN （total nitrogen）, NH4^＋-N, NO3^--N, TP （total phosphorus）, PO4^3-P from the mixed forest land were 1.794, 3.498, 1.462, 10.269, 0.862, 0.044, 0.634, 0.034, and 0.005 mg/L, respectively. The annual unit loads of BOD, COD, DOC, SS, TN, NH4^＋-N, NO3^--N, TP and PO4^3--P were estimated as 66.9, 133.2, 55.5, 429.8, 36.5, 1.6, 26.9, 1.3 and 0.1 kg/（ha·yr）, respectively. In addition, affecting parameters on the EMCs were investigated by statistic analysis of the field data. As a result, significant correlations with precipitation, rainfall intensity, and total runoff flows were found in most constituents.

关键词： event mean concentration mixed forest land use non-point source pollutant load unit load

Distributed Simulation of non-point source Pollution in Ashi River Basin

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Journal of Harbin Institute of Technology(New Series) 2015年第3期22卷 31-39页

作者： Fang Ma Xiaofeng Jiang Li Wang Zhe Li Xiongwei Liang State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology HIT Yixing Academy of Environmental Protection

In order to get a thorough understanding of non-point source pollution,it is essential to examine its temporal and spatial distribution. A physically-based distributed model,Soil and Water Assessment Tool( SWAT),was used in this research,to quantitatively estimate the NPS load and analyze the temporal and spatial distributions of NPS pollution in Ashi River Basin. The results indicated that SWAT was suitable to simulate stream-flow and water quality in Ashi River Basin. Total Nitrogen which was contributed by NPS( NPS-TN) accounted for 32. 47%-62. 61%,and Total Phosphorus which was contributed by NPS( NPS-TP)accounted for 22. 30%- 57. 85% of the total load respectively. In inter-annual timescale,both NPS-TN and NPS-TP were influenced by stream-flow and fertilizer. However,when compared with fertilizer,NPS pollution was more directly affected by stream-flow. In annual timescale,NPS-TN and NPS-TP mainly occurred in flood season( from May to September). In the aspect of space,spatial differences of NPS-TN and NPS-TP were extremely significant. The spatial variations of NPS pollution were mainly influenced by land use,precipitation,soil and slope.

关键词： SWAT model non-point source nitrogen phosphorus Ashi River Basin

Estimation of Nitrogen Export from non-point source in a forest-dominant sub-catchment of Poyang Lake Watershed, China

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Estimation of Nitrogen Export from Non-point Source in a for...

What drives the change of nitrogen and phosphorus loads in the Yellow River Basin during 2006-2017?

International Conference on Environmental Pollution and Public Health(EPPH 2012) Vol1

作者： Xiu-li Xu Qi Zhang Xiang-hu Li Min Shao Yun-liang Li Li-ming Jin State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

Catchment-generated non-point source pollution is a severe problem in China. This paper, exemplified in the Leanjiang catchment of Poyang Lake watershed, investigated river water quality of nitrogen concentration variations via setting up regular water quality monitoring points at different river levels with different land use types composition. Results indicated that the peak nitrogen concentration occurred in wet seasons, and the lowest concentration was in dry seasons. The spatial variation of nitrogen concentration demonstrated a low value at the upstream area to a high value at the downstream. In addition, the relationship between land use composition and nitrogen export coefficient showed that nitrogen export coefficient increased with a higher percentage of arable land area and a lower percentage of forest land area. A quantitative analysis further indicated that the nitrogen export coefficient for arable land is 3.92mg/L, and for forest land is 0.71mg/L.

关键词： non-point source nitrogen export coefficient Poyang Lake watershed

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Journal of Environmental Sciences 2023年第4期126卷 17-28页

作者： Jiaqi Zheng Xianghui Cao Chunzi Ma Nanyan Weng Shouliang Huo State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental ScienceBeijing 100012China

The Yellow River Basin (YRB) plays a very important role in China’s economic and social development and ecological *** particular,the ecosystem of the YRB is sensitive to climate ***,the change of nutrient fluxes in this region during the past years and its main driving forces remain *** this study,a hydrologic model R System for Spatially Referenced Regressions on Watershed Attributes (RSPARROW) was employed to simulate the spatio-temporal variations in the fluxes of total nitrogen (TN) and total phosphorus (TP) during the period of *** results suggested that the TN and TP loads increased by 138%and 38%during 2006-2014,respectively,and decreased by 66%and 71%from 2015 to 2017,*** the period of 2006-2017,the annual mean fluxes of TN and TP in the YRB were in the range of 3.9 to 591.6 kg/km^(2)/year and 1.7 to 12.0 kg/km^(2)/year,*** flux was low in the upstream area of the Yellow River,and presented a high level in the middle and lower ***,the flux of TP in Gansu and Ningxia section was slightly higher than that in the lower reaches of the Yellow *** and point source are the key drivers for the inter-annual changes of TN loads in most regions of the *** the inter-annual variations of TP loads in the whole basin are mainly driven by the point *** study demonstrates the important impacts of climate change on nutrient loads in the ***,management measures should be taken to reduce pollution sources and thus provide solid basis for control of nitrogen and phosphorus in the YRB.

关键词： Yellow river basin Nutrient loads Climate change non-point source point source

ENHANCING RAINFALL-RUNOFF POLLUTION MODELING BY INCORPORATION OF NEGLECTED PHYSICAL PROCESSES

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Frontiers of Agricultural Science and Engineering 2023年第4期10卷 553-565页

作者： Mingjin CHENG Xin LIU Han XIAO Fang WANG Minghao PAN Zengwei YUAN Hu SHENG State Key Laboratory of Pollution Control and Resource Reuse School of EnvironmentNanjing UniversityNanjing 210023China Lishui Institute of Ecology and Environment Nanjing UniversityNanjing 211200China

The growing need to mitigate rainfall-runoff pollution,especially first flush,calls for accurate quantification of pollution load and the refined understanding of its spatial-temporal *** wash-off model has advantages in modeling rainfall-runoff pollution due to the inclusion of two key physical processes,build-up and ***,this disregards pollution load from wet precipitation and the relationship between rainfall and runoff,leading to uncertainties in model *** study integrated the Soil Conservation Service curve number(SCS-CN)into the wash-off model and added pollutant load from wet precipitation to enhance the rainfall-runoff pollution *** enhanced wash-off model was validated in a typical rural-residential *** results showed that the model performed better than the established wash-off model and the commonly-used event mean concentrations method,and identified two different modes of pollution characteristics dominated by land pollution and rainfall pollution,*** addition,the model simulated more accurate pollutant concentrations at *** this,it was found that 12%of the total runoff contained 80%to 95%of the total load for chemical oxygen demand,total N,and total P,whereas it contained only 15%of the total load for NH4+-*** enhanced model can provide deeper insights into non-point pollution mitigation.

关键词： Erhai Lake field experiment non-point source pollutionn load rainfall runoff wash-off model

Linking Management and Riparian Physical Functions to Water Quality and Aquatic Habitat

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Journal of Water Resource and Protection 2016年第8期8卷 797-815页

作者： Donald F. Kozlowski Robert K. Hall Sherman R. Swanson Daniel T. Heggem USDA Forest Service Beckwourth Ranger District Plumas National Forest Blairsden CA USA USEPA Region IX WTR2 San Francisco CA USA Natural Resources & Environmental Sciences University of Nevada Reno NV USA USEPA Office of Research & Development NERL Environmental Sciences Division Las Vegas NV USA

Stream and wetland riparian areas are able to sustain a state of resiliency based on the ecosystem’s ability to attain the functions of its ecological potential. This resiliency allows an area to provide and produce desired and valued water quality and aquatic habitat ecosystem services. Maintaining healthy aquatic and riparian habitats depends on “management” allowing for, or facilitating natural recovery of riparian functions. Altering grazing management practices in Maggie Creek lead to changes in riparian functionality, water quality, and aquatic habitat. Maggie Creek basin, historically renowned for its fishery, is one of only a few watersheds in Nevada capable of supporting Lahontan Cutthroat Trout (LCT) (Oncorhynchus clarkia ssp. Henshawi) meta-populations. Prior to 1993, the majority of Maggie Creek was grazed by cattle throughout the growing season. Decades of intensive grazing, water development, and road construction degraded aquatic and riparian habitats. By the early 1990’s, a majority of the Maggie Creek watershed was rated as nonfunctional or functional-at-risk condition with unstable banks, channel incision, loss of riparian vegetation, wide shallow channels, excessive erosion and deposition, reduced stream flows, and increased water temperatures. As mitigation for their 1993 South Operations Area Project mine dewatering, Newmont Mining Company, in cooperation with the Elko District Bureau of Land Management (BLM) and the Elko Land and Livestock Company, developed the Maggie Creek Watershed Restoration Project to enhance LCT habitat. The project was developed to enhance 82 miles of stream, 2000 acres of riparian habitat and 40,000 acres of upland watershed primarily through prescriptive livestock management. Beginning in 1994, grazing systems were implemented for portions of the perennial/intermittent streams. This greatly reduced the frequency and duration of hot season grazing on Maggie Creek and its tributaries. The objective of this paper is to c

关键词： Ecosystem Function Water Quality non-point source Proper Functioning Condition