The deteriorating water quality in the Taihu Lake Basin has attracted widespread attention for many years, and is correlated with a sharp increase in the quantity of pollutant discharge such as agricultural fertilizer...The deteriorating water quality in the Taihu Lake Basin has attracted widespread attention for many years, and is correlated with a sharp increase in the quantity of pollutant discharge such as agricultural fertilizers and industrial wastewater. In this study, several factors were selected for evaluating and regionalizing the water environmental capacity by ArcG1S spatial analysis, including geomor- phologic characteristics, water quality goals, water body accessibility, water-dilution channels, and current water quality. Then, the spa- tial optimization of agriculture and industry was adjusted through overlay analysis, based on the balance between industrial space and water environmental capacity. The results show that the water environmental capacity gradually decreases from the west to the east, in contrast, the pollution caused by industrial and agricultural clustering is distributes along Taihu Lake, Gehu Lake and urban districts. The analysis of the agricultural space focuses on optimizing key protected areas of the Taihu Lake Basin, and the shores of Gehu Lake, optimally adjusting the second protected areas of the Taihu Lake Basin, and generally adjusting the urban areas of Changzhou and Wuxi cities. The analysis of industrial space focuses on optimizing the downtowns of Changzhou and Wuxi cities, optimally adjusting key protected areas and second protected areas of the Taihu Lake Basin, and generally adjusting the south and southwest of Gehu Lake. Lastly, some schemes of industrial and agricultural layouts and policies for the direction of industrial and agricultural development were proposed, reflecting a correlation between industry and agriculture and the water environment.展开更多
There are a number of factors that contribute to heavy metal contamination in agricultural soils including deficient management of solid waste, waste water discharge, irrigation with contaminated water, and use of fer...There are a number of factors that contribute to heavy metal contamination in agricultural soils including deficient management of solid waste, waste water discharge, irrigation with contaminated water, and use of fertilizers and pesticides. The aim of this study is to estimate the sources and the levels of metals in soils of the ULB (Upper Litani Basin) that receive all mentioned factors. Soil samples were collected during the dry season from 24 sites along the Litani River flow, and 12 sites irrigated by Canal 900 withdrawn from the Qaraoun Dam along river. Metals in soils were analyzed using EDXRF (energy dispersive X-ray fluorescence) technique. Data revealed the following average levels of some heavy metals in soils with high percentage of samples exceeding the international guidelines: Mn (593 mg/kg)--67%, Ni (98 mg/kg)--96%, Cr (143 mg/kg)--92%, Hg (3.6 mg/kg)--38%, Cd (2.8 mg/kg)---25% and As (17.6 mg/kg)-84%. In canal soils: Mn (683 mg/kg)-86%, Ni (156 mg/kg)-100%, Cr (203 mg/kg) -100%, Hg (2.3 mg/kg)-25%, Cd (3.3 mg/kg)-25% and As (19.5 mg/kg)-92%. The prime source of toxic metals was due to the agricultural runoffs, beside sewage and domestic waste water discharge. Thus, the prominent findings of high levels of toxic metals (Cr, Cd, Hg and As) in soils and consequent probability in plants might induce a major health threat to consumers,展开更多
基金Under the auspices of National Natural Science Foundation of China (No. 41130750,70703033)'135' Strategic Development Planning Project of Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences (No. 2012135006)
文摘The deteriorating water quality in the Taihu Lake Basin has attracted widespread attention for many years, and is correlated with a sharp increase in the quantity of pollutant discharge such as agricultural fertilizers and industrial wastewater. In this study, several factors were selected for evaluating and regionalizing the water environmental capacity by ArcG1S spatial analysis, including geomor- phologic characteristics, water quality goals, water body accessibility, water-dilution channels, and current water quality. Then, the spa- tial optimization of agriculture and industry was adjusted through overlay analysis, based on the balance between industrial space and water environmental capacity. The results show that the water environmental capacity gradually decreases from the west to the east, in contrast, the pollution caused by industrial and agricultural clustering is distributes along Taihu Lake, Gehu Lake and urban districts. The analysis of the agricultural space focuses on optimizing key protected areas of the Taihu Lake Basin, and the shores of Gehu Lake, optimally adjusting the second protected areas of the Taihu Lake Basin, and generally adjusting the urban areas of Changzhou and Wuxi cities. The analysis of industrial space focuses on optimizing the downtowns of Changzhou and Wuxi cities, optimally adjusting key protected areas and second protected areas of the Taihu Lake Basin, and generally adjusting the south and southwest of Gehu Lake. Lastly, some schemes of industrial and agricultural layouts and policies for the direction of industrial and agricultural development were proposed, reflecting a correlation between industry and agriculture and the water environment.
文摘There are a number of factors that contribute to heavy metal contamination in agricultural soils including deficient management of solid waste, waste water discharge, irrigation with contaminated water, and use of fertilizers and pesticides. The aim of this study is to estimate the sources and the levels of metals in soils of the ULB (Upper Litani Basin) that receive all mentioned factors. Soil samples were collected during the dry season from 24 sites along the Litani River flow, and 12 sites irrigated by Canal 900 withdrawn from the Qaraoun Dam along river. Metals in soils were analyzed using EDXRF (energy dispersive X-ray fluorescence) technique. Data revealed the following average levels of some heavy metals in soils with high percentage of samples exceeding the international guidelines: Mn (593 mg/kg)--67%, Ni (98 mg/kg)--96%, Cr (143 mg/kg)--92%, Hg (3.6 mg/kg)--38%, Cd (2.8 mg/kg)---25% and As (17.6 mg/kg)-84%. In canal soils: Mn (683 mg/kg)-86%, Ni (156 mg/kg)-100%, Cr (203 mg/kg) -100%, Hg (2.3 mg/kg)-25%, Cd (3.3 mg/kg)-25% and As (19.5 mg/kg)-92%. The prime source of toxic metals was due to the agricultural runoffs, beside sewage and domestic waste water discharge. Thus, the prominent findings of high levels of toxic metals (Cr, Cd, Hg and As) in soils and consequent probability in plants might induce a major health threat to consumers,