The precipitation recharge coefficient(PRC), representing the amount of groundwater recharge from precipitation, is an important parameter for groundwater resources evaluation and numerical simulation. It was usually ...The precipitation recharge coefficient(PRC), representing the amount of groundwater recharge from precipitation, is an important parameter for groundwater resources evaluation and numerical simulation. It was usually obtained from empirical knowledge and site experiments in the 1980 s. However, the environmental settings have been greatly modified from that time due to land use change and groundwater over-pumping, especially in the Beijing plain area(BPA). This paper aims to estimate and analyze PRC of BPA with the distributed hydrological model and GIS for the year 2011 with similar annual precipitation as long-term mean. It is found that the recharge from vertical(precipitation + irrigation) and precipitation is 291.0 mm/yr and 233.7 mm/yr, respectively, which accounts for 38.6% and 36.6% of corresponding input water. The regional mean PRC is 0.366, which is a little different from the traditional map. However, it has a spatial variation ranging from –7.0% to 17.5% for various sub-regions. Since the vadose zone is now much thicker than the evaporation extinction depth, the land cover is regarded as the major dynamic factor that causes the variation of PRC in this area due to the difference of evapotranspiration rates. It is suggested that the negative impact of reforestation on groundwater quantity within BPA should be well investigated, because the PRC beneath forestland is the smallest among all land cover types.展开更多
Vulnerability research is the core issue and one of the research hotspots of sustainable development science.Vulnerability and its evaluation framework provide a new perspective for rural social-ecosystem studies.This...Vulnerability research is the core issue and one of the research hotspots of sustainable development science.Vulnerability and its evaluation framework provide a new perspective for rural social-ecosystem studies.This paper introduced the‘input-output’efficiency theory and constructed the‘SEE-PSR’framework for the analysis of social-ecosystem vulnerability in the rural area in Qingpu District of Shanghai City.The DEA models,spatial autocorrelation model,multivariate logistic regression model,geographical detector and hierarchical cluster model were used to analyze the spatial differences of social-ecosystem vulnerability,and its geographical impact mechanisms and ecological restorations,in 184 administrative villages in this area.The results can be divided into three main points.(1)The results of the‘input-output’efficiency model of the EW-DEA based on entropy weight aggregation crossover was more reliable and accurate for the evaluation of rural social-ecosystem vulnerability.The vulnerability of the social-ecosystems in the administrative villages showed a trend of gradual decline from east to west,with an average value of vulnerability of 0.583,and the vulnerability of social systems had become an important factor in constraining the decrease of the vulnerability of the social-ecosystems in the region.(2)The distances from the center of Shanghai City,from Dianshan Lake,from the center of Qingpu District and from the water area were the four dominant geographical factors affecting the vulnerability of the social-ecosystem in this region.The geographical impacts exhibited the spatial differentiations of systemic structure,the substitution of typological attributes and the transformation level.(3)The geographical factors coupling the impact types of the social-ecosystem vulnerability were divided spatially into 10 types.The geographic multi-factor coupling impact types were dominant,which presented multi-cyclic spatial patterns and were dominated by the central multi-factor which was surrounded by the single factor types on both sides.According to the different types,some feasible ways of ecological restoration were proposed,which drew on the experiences of integrated territory consolidation to remediate the vulnerability of rural social-ecological systems.The results of this study can provide scientific reference for rural spatial reconstruction,regional ecological restoration and sustainable development for the regions characterized by conflict in the‘strict protection of the ecological environment and vigorous development of the economy’.展开更多
基金Under the auspices of Beijing Natural Science Foundation(No.8152012)National Natural Science Foundation of China(No.41101033,41130744,41171335)
文摘The precipitation recharge coefficient(PRC), representing the amount of groundwater recharge from precipitation, is an important parameter for groundwater resources evaluation and numerical simulation. It was usually obtained from empirical knowledge and site experiments in the 1980 s. However, the environmental settings have been greatly modified from that time due to land use change and groundwater over-pumping, especially in the Beijing plain area(BPA). This paper aims to estimate and analyze PRC of BPA with the distributed hydrological model and GIS for the year 2011 with similar annual precipitation as long-term mean. It is found that the recharge from vertical(precipitation + irrigation) and precipitation is 291.0 mm/yr and 233.7 mm/yr, respectively, which accounts for 38.6% and 36.6% of corresponding input water. The regional mean PRC is 0.366, which is a little different from the traditional map. However, it has a spatial variation ranging from –7.0% to 17.5% for various sub-regions. Since the vadose zone is now much thicker than the evaporation extinction depth, the land cover is regarded as the major dynamic factor that causes the variation of PRC in this area due to the difference of evapotranspiration rates. It is suggested that the negative impact of reforestation on groundwater quantity within BPA should be well investigated, because the PRC beneath forestland is the smallest among all land cover types.
基金The National Natural Science Foundation of China(41471455)The Social Science Foundation of Hunan Province(20JD011)+2 种基金The Social Science Review Foundation of Hunan Province(XSP17YBZC021,XSP18ZDI035)The Humanities and Social Science Research Project of Hunan Education Department(19A086)The Key Laboratory of Key Technologies of Digital Urban-Rural Spatial Planning of Hunan Province(2018TP1042)。
文摘Vulnerability research is the core issue and one of the research hotspots of sustainable development science.Vulnerability and its evaluation framework provide a new perspective for rural social-ecosystem studies.This paper introduced the‘input-output’efficiency theory and constructed the‘SEE-PSR’framework for the analysis of social-ecosystem vulnerability in the rural area in Qingpu District of Shanghai City.The DEA models,spatial autocorrelation model,multivariate logistic regression model,geographical detector and hierarchical cluster model were used to analyze the spatial differences of social-ecosystem vulnerability,and its geographical impact mechanisms and ecological restorations,in 184 administrative villages in this area.The results can be divided into three main points.(1)The results of the‘input-output’efficiency model of the EW-DEA based on entropy weight aggregation crossover was more reliable and accurate for the evaluation of rural social-ecosystem vulnerability.The vulnerability of the social-ecosystems in the administrative villages showed a trend of gradual decline from east to west,with an average value of vulnerability of 0.583,and the vulnerability of social systems had become an important factor in constraining the decrease of the vulnerability of the social-ecosystems in the region.(2)The distances from the center of Shanghai City,from Dianshan Lake,from the center of Qingpu District and from the water area were the four dominant geographical factors affecting the vulnerability of the social-ecosystem in this region.The geographical impacts exhibited the spatial differentiations of systemic structure,the substitution of typological attributes and the transformation level.(3)The geographical factors coupling the impact types of the social-ecosystem vulnerability were divided spatially into 10 types.The geographic multi-factor coupling impact types were dominant,which presented multi-cyclic spatial patterns and were dominated by the central multi-factor which was surrounded by the single factor types on both sides.According to the different types,some feasible ways of ecological restoration were proposed,which drew on the experiences of integrated territory consolidation to remediate the vulnerability of rural social-ecological systems.The results of this study can provide scientific reference for rural spatial reconstruction,regional ecological restoration and sustainable development for the regions characterized by conflict in the‘strict protection of the ecological environment and vigorous development of the economy’.
