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Total Nitrogen and Total Phosphorus Pollution Reshaped the Relationship Between Water Supply and Demand in the Huaihe River Watershed, China

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Chinese Geographical Science 2023年第3期33卷 512-530页

作者： LU Yan LIU Lyuyi QIN Fen WANG Jiayao LIU Jianzhong LI Yingjie WAN Luwen School of Geoscience and Technology Zhengzhou UniversityZhengzhou 450001China Henan Provincial Academy of Eco-Environmental Sciences Zhengzhou 450003China Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions Ministry of EducationHenan UniversityKaifeng 475000China Henan Industrial Technology Academy of Spatio-Temporal Big Data Henan UniversityKaifeng 475000China College of Geography and Environmental Science Henan UniversityKaifeng 475000China Environmental Science and Policy Program Michigan State UniversityEast LansingMI 48824USA

As total nitrogen(TN)and total phosphorus(TP)pollution is the main source of water pollution in the Huaihe River Watershed in China,it is important to understand how TN and TP pollution affect the relationship between water supply and demand.Quantifying their impacts and describing the spatiotemporal distribution of these relationships are necessary for furtherly deepening the theory of TN and TP pollution on water bodies,and this information is also particularly essential for managing water resources regionally.In this study,based on the potential water supply,the water demand and the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)water purification models,we estimated the TN and TP pollution from agricultural fertilizer,livestock and poultry breeding,and rural residents in the Huaihe River Watershed and simulated TN and TP impacts on the relationship between water supply and demand.We found that if the impact of TN and TP pollution on water supply was not taken into account,on average,there was excess water supply in 79.20%of the Watershed and excess demand in 20.80%of the rest during 1980–2018.Under the TN concentration limit,Grade-Ⅱ(The water quality meets the secondary level of water body qualified in GB3838–2002,classified as Grade-II)water was the main watersupply type in 1980–2018,followed by Grade-Ⅰ and Grade-Ⅲ water.The total water shortage showed an inverted V-shaped trend:first increasing and then decreasing at the same period.The proportion of the water shortage of Grade-I water in the total water shortage was the largest,followed by Grade-Ⅱ and Grade-III water.Areas with excess demand were located on the north bank of Wang-Beng,Yishuhe,and Huxi regions,although the water in these sub-Watersheds met the water quality standards of Grade-Ⅰ water.Under the TP concentration limit,Grade-Ⅱ and Grade-Ⅰ water were the main water-supply types.The overall water shortage trend first increased and then decreased,exhibiting an inverted V-shape from 1980 to 2018.The water shortages of Grade-Ⅰ and

关键词： Watershed breeding poultry

Spatial and Temporal Change of Habitat Quality of Poyang Lake Basin in China at Small Watershed Scale and Its Multidimensional Response to Landscape Pattern

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Chinese Geographical Science 2023年第3期33卷 565-582页

作者： BI Manyu ZHONG Yexi XIAO Zeping FENG Xinghua MA Hongzhi School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China Key Laboratory of Poyang Lake Wetland and Watershed Research Ministry of Education(Jiangxi Normal University) Nanchang 330022China

The health and function of ecosystems are largely determined by the quality of habitat,and the optimal regulation of landscape patterns has become an important way to improve regional habitat quality.This article takes the Poyang Lake Basin of China as a case,reveals the spatial and temporal change of its habitat quality at the small Watershed scale,and attempts to examine the multidimensional response of habitat quality to landscape pattern changes with respect to landscape compositions and landscape configuration.The results show:1)from 2000 to 2020,the overall landscape fragmentation of the basin decreased,the landscape aggregation in the central small Watersheds changed significantly,and the spatial distribution of landscape elements in the central and southern small Watersheds were relatively homogeneous.2)The overall habitat quality of the Poyang Lake Basin is at a middle to high level,with significant spatial differentiation,showing the distribution characteristics of‘high in the periphery,low in the center,high in the south and low in the north’.3)Both landscape compositions and landscape configurations influenced habitat quality,but there were obvious differences in the response degree.From the landscape composition and configuration dimension,the influence of landscape composition on habitat quality was greater than that of landscape configuration;from the multilevel landscape configuration dimension,compared to landscape level,landscape configuration at the class level impacted habitat quality more deeply.To the end,this article proposes a differentiated regulation strategy for habitat quality conservation in small Watersheds from the perspective of landscape patterns to improve the ecological service level of Poyang Lake Basin.

关键词： landscape Watershed Spatial

Evolution of gully erosion and susceptibility factors in the urban Watershed of the Kimemi(Butembo/DR Congo)

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Geography and Sustainability 2023年第3期4卷 268-279页

作者： Jonathan Ahadi Mahamba Gloire Mulondi Kayitoghera Moise Kapiri Musubao Géant Basimine Chuma Walere Muhindo Sahani Laboratoire d’Ecologie Géomorphologie et Géomatique(LEGG)UniversitéCatholique du GrabenButemboDemocratic Republic of Congo Faculty of Agricultural Sciences UniversitéCatholique du Graben(UCG)P.O.Box 29 ButemboNorth-KivuDemocratic Republic of Congo Faculty of Agricultural and Environment sciences UniversitéEvangélique en Afrique(UEA)P.O.Box:3323 BukavuSouth-KivuDemocratic Republic of Congo Laplec UR SPHERES Department of GeographyUniversity of LiegeClos Mercator 34000LiègeBelgium

Gully erosion is one of the most intense landscape degradation mechanisms in areas with varying environmental characteristics.Both natural and anthropogenic factors affect the gullying process.Reliable documentation of these processes in tropical African cities is scarce.This study assessed the gully erosion dynamic and the sus-ceptibility factors in the urban Watershed of Kimemi in eastern Democratic Republic of Congo(DRC).Data were obtained through a combination of fieldwork and digitization of very high spatial resolution images from Google Earth(from 2011 to 2021).The length,width,and area of large gullies(width≥5 m)were measured for each year of the study.A logistic regression model(LRM)was also used to investigate the influence of both physical and anthropogenic factors on gully susceptibility.The results revealed that the number of gullies has increased from 36 to 61 during the last decade.The gully mean length of 63.9±61.1 m,129.3±104.9 m,and 174.7±153.8 m were obtained for the years 2011,2015,and 2021 respectively.The average density of gully network for the study period was 0.12 km/km^(2),while the degraded land was -1.3 and -1.1 ha/year for 2011-2015 and 2015-2021 for the entire Watershed.The significant changes in morphometric parameters(length,width,area)were found only in the bare land and building land uses.A strong and positive relationship between the length(m)and the area(ha)was found.Furthermore,the susceptibility of gullying was significantly influenced by the slope,stream power index(SPI),distance to roads and rivers,land use and land cover(LULC),and normalized difference vegetation index(NDVI).This means the areas located in the bare land and building or close to roads and/or streams are more likely to be gullied.The findings emphasize the impact of urbanization on gully erosion in the Kimemi Watershed,highlighting the importance of informed land management decisions with a close attention to anthropogenic factors.

关键词： Soil erosion Gully susceptibility LRM Urbanization Watershed Butembo

Development of a model to simulate soil heavy metals lateral migration quantity based on SWAT in Huanjiang Watershed,China

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Journal of Environmental Sciences 2019年第3期31卷 115-129页

作者： Pengwei Qiao Mei Lei Sucai Yang Jun Yang Xiaoyong Zhou Nan Dong Guanghui Guo Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing Key Laboratory of Remediation of Industrial Pollution Sites Environmental Protection Research Institute of Light Industry Comprehensive Institute of Geotechnical Investigation and Surveying Ltd.

Lateral transportation of soil heavy metals in rainfall events could significantly increase the scope of pollution. Therefore, it is necessary to develop a model with high accuracy to simulate the migration quantity of heavy metals. A model for heavy metal migration simulation was developed based on the SWAT(Soil and Water Assessment Tool) model. This model took into consideration the influence of soil p H value, soil particle size, runoff volume, sediment amount,concentration of water-soluble heavy metals dissolved in runoff and insoluble absorbed to the soil particles. This model was reasonable in Huanjiang Watershed, Guangxi Zhuang Autonomous Region, south China, covering an area of 273 km^2. The optimal drainage area threshold was determined by analyzing the effects of Watershed subdivision on the simulation results to ensure the simulation accuracy. The main conclusions of this paper were:(1) Watershed subdivision could affect simulation migration quantity of heavy metals;(2) the quantity of heavy metals transported by sediment accounted for 97%–99% of the total migration quantity in the study Watershed. Therefore, sediment played the most important role in heavy metal migration;(3) the optimal drainage area threshold percentage to ensure high simulation accuracy was determined to be 2.01% of the total Watershed;(4) with the optimal threshold percentage, this model could simulate the migration quantity of As, Pb and Cd accurately at the total Watershed and subWatershed level. The results of this paper were useful for identifying the key regions with heavy metal migration.

关键词： Soil heavy metal migration Simulation model Watershed subdivision Optimal drainage area threshold percentage Simulation accuracy

Spatial distribution and source identification of heavy metals (As, Cr, Cu and Ni) at sub-Watershed scale using geographically weighted regression

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International Soil and Water Conservation Research 2019年第3期7卷 308-315页

作者： Maziar Mohammadi Abdulvahed Khaledi Darvishan Nader Bahramifar Department of Watershed Managerment Engineering Faculty of Natural ResourcesTarbiat Modares University***Mazandaran Provincelran Department of Environmental Science Faculty of Natural ResourcesTarbiat Modares University***Mazandaran ProvinceIran

Heavy metals are among the most important sources of water and soil pollution.These elements accumulate in the agricultural soil through using contaminated water for irrigation,fertilizers,pesticide and enter to the river systems by water erosion.Therefore,land use plays a serious role in water and sediment pollution.In this regards,geographically weighted regression was used to investigate the spatial correlation between sediment heavy metals and land uses in a highland Watershed.The landuse map was used to calculate the area percentage of landuse types in sub-Watersheds,followed by geographically weighted regression method to investigate the spatial correlation of As,Cr,Cu and Ni versus three types of land uses.The highest correlation was observed for irrigated plots versus As and Ni in upstream and for rainfed plots versus AS,Ni and Cr in the downstream.The relationship between heavy metals and developed lands was more complicated and the highest correlation was found for Ni and As at outlet (R2 =0.52-0.89),for Cr in the upstream (R2 =0.50-0.76),and for Cu in the upstream and downstream (R2 =0.36-0.60).The results indicated that there is a positive correlation between heavy metals and land uses which varies with the level of agricultural and urbanization development at subWatershed.Based on the findings,appropriate policies and decisions should be taken on agricultural land to prevent the transfer of heavy metals by sediment to aquatic environments.

关键词： Land use Sediment pollution GWR Talar Watershed

Farmers' decision to adopt Watershed management practices in Gibe basin, southwest Ethiopia

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International Soil and Water Conservation Research 2019年第4期7卷 376-387页

作者： Fekadu Mengistu Engdawork Assefa Center for Environment and Development Studies Addis Ababa UniversityAddis AbabaEthiopia Department of Geography and Environmental Studies Debre Berhan UniversityDebre BerhanEthiopia

Watershed management practices have been implemented to avert land degradation and to enhance people's livelihoods in the highlands of Ethiopia for several years.However,the successes of these practices have been quite limited and the main factors affecting these practices have not been examined in detail.This study intended to investigate rates and intensities of adoption of Watershed management practices and to determine the main factors affecting farmers' adoption decisions in the upper Gibe basin.Data were collected from 304 household heads in six sub catchments across different topographic settings using household interview.Focus groups discussions,key informant interviews and transect walk observations were also used.Descriptive statistics and econometric models such as,multivariate and ordered probit were used to analyze the data.The results revealed that the majority of households (82.6 percent) used at least one of the six practices considered in this study.Soil bund,grass strip cultivation with soil bund and compost were the major Watershed management practices adopted by farmers.Adoption rate and intensity of adoption were better for program participants and in upper and middle topographic settings.The results of the multivariate and ordered probit analysis indicated that household size,extension services,credit services,training services and perception of soil erosion had positive significant relationship with both rate and intensity of adoption of most practices.Hence,policy makers and planners need to consider labor,knowledge and awareness,and capital intensive nature of the practices for the up scaling planning and implementations of Watershed intervention technologies.

关键词： Watershed management practices Farmers' decision Adoption Determinants Gibe river basin

Using Vetiver grass technology for mitigating sediment loads in the Talakhaya Watershed areas in Rota, CNMI

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International Soil and Water Conservation Research 2018年第2期6卷 194-201页

作者： Mohammad HGolabi Sydonia Manibusan Timothy Righetti Dana Okano Clancy Iyekar University of Guam USA National Oceanic and Atmospheric Administration CNMIUSA

Talakhaya Watershed in Rota is identified as a Coral Reef Management Priority site for CNMI (Com-monwealth of Northern Mariana Islands). In 2010 federal and jurisdictional partners developed a Con-servation Action Plan (CAP) for the Talakhaya Watershed. The goal of this initial Watershed Soil Loss Assessment therefore, was to assist in evaluating the re-vegetation objectives of 'Mitigating Sediment Load' in the Talakhaya Watershed by making a thorough characterization of its main river systems. The objectives of this project were to reach those goals by measuring the hydrological parameters following the installation and the use of water meters, barometric level loggers, turbidity meters and rain gauges. The water flow as well as the turbidity level of each stream leading to the ocean from the Talakhaya Watershed was measured and sedimentation level was assessed accordingly. The results from the monitoring of the Watershed conducted during the project timeline reported here show that all four rivers under study have statistically different stage-discharge curves. The river's relationship between time and turbidity also vary especially in the summer months of the first-year observations. Linear and convex polynomial relationships were sometimes observed in the different rainfall groupings for the four river systems, however relationships were often not significant. This-being-said, Quantile Regressions suggest that when data from all four river systems are combined for cases where there is some de-tectable rainfall, a maximum possible turbidity level can be defined.

关键词： Watershed Management Vetiver grass system Coral Badlands Micronesia Rota CNMI

Impacts of water surface area of Watershed on design flood

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Water Science and Engineering 2014年第1期7卷 41-48页

作者： Qing-hua ZHANG Yan-fang DIAO Jie DONG College of Water Conservancy and Civil Engineering Shandong Agricultural University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University

In order to analyze the impact of the water surface area of a Watershed on the design flood, the Watershed was classified into a land Watershed and a water surface Watershed for flood flow calculation at the same time interval. Then, the design flood of the whole Watershed was obtained by adding the two flood flows together. Using this method, we calculated design floods with different water surface areas of three reservoirs and analyzed the impact of water surface area on the flood volume and peak flow. The results indicate that larger water surface areas lead to greater impacts on the flood volume and peak flow. For the same Watershed area, the impact of water surface area on the flood volume and peak flow is positively proportional to the flood frequency, i.e., the higher the frequency, the greater the impact becomes.

关键词： Watershed water surface area design flood, flood frequency flood volume peak Jlow

Hydrochemical characteristics and geochemistry evolution of groundwater in the plain area of the Lake Baiyangdian Watershed,North China Plain

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Journal of Groundwater Science and Engineering 2018年第3期6卷 220-233页

作者： ZHANG Yu-qin WANG Guang-wei WANG Shi-qin YUAN Rui-qiang TANG Chang-yuan SONG Xian-fang Key Laboratory of Agricultural Water Resources Hebei Laboratory of Agricultural Water-SavingCenter for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China University of Chinese Academy of Sciences Beijing 100049China Faculty of Horticulture Chiba UniversityMatsudo-city271-8510Japan School of Environmental Sciences&Resources Shanxi UniversityTaiyuan 030006China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Water cycle and water quality in the Lake Baiyangdian Watershed of the North China Plain have undergone great changes due to over-pumping of groundwater and wastewater discharge.In this paper,hydrogeochemical data was collected to analyze the hydrochemical characteristics and geochemistry evolution of groundwater.The study area was divided into two typical parts.One was in the upstream plain area,where over-pumping had resulted in significant decline of groundwater level;the other one was located in the downstream area near the Fu River and Lake Baiyangdian(Lake BYD region).In addition to the natural weathering of minerals,excessive fertilizer was also a main factor of higher ion concentration in groundwater.According to studies,due to good permeability,these regions were easy to be polluted even with deep groundwater depth.However,upstream shallow groundwater and surface water,including lake water,domestic along with industrial wastewater were all sources of present shallow groundwater in the Lake BYD region.Results indicated that anthropogenic activities rather than minerals much matter to the groundwater in these regions.Particularly,wastewater largely decided the groundwater quality,which suggested that the management and restoration of surface water quality was crucial to groundwater protection.

关键词： Hydrochemical characteristics Geochemical processes Groundwater The Lake Baiyangdian Watershed North China Plain