The Huai River Basin is a unique area in P.R.China with the highest densities of population and water projects.It is also subject to the most serious water pollution.We proposed a distributional SWAT(Soil and Water As...The Huai River Basin is a unique area in P.R.China with the highest densities of population and water projects.It is also subject to the most serious water pollution.We proposed a distributional SWAT(Soil and Water Assessment Tool) model coupled with a water quality-quantity balance model to evaluate dam impacts on river flow regimes and water quality in the middle and upper reaches of the Huai River Basin.We calibrated and validated the SWAT model with data from 29 selected cross-sections in four typical years(1971,1981,1991 and 1999) and used scenario analysis to compensate for the unavailability of historical data regarding uninterrupted river flows before dam and floodgate construction,a problem of prediction for ungauged basins.The results indicate that dam and floodgate operations tended to reduce runoff,decrease peak value and shift peaking time.The contribution of water projects to river water quality deterioration in the concerned river system was between 0 to 40%,while pollutant discharge contributed to 60% to 100% of the water pollution.Pollution control should therefore be the key to the water quality rehabilitation in the Huai River Basin.展开更多
The major concern of this article is to address the shortcoming and outgoing effects of the human activities on the landscape patterns and their consequences in the Sefidrood River watershed in Iran. A flow of data in...The major concern of this article is to address the shortcoming and outgoing effects of the human activities on the landscape patterns and their consequences in the Sefidrood River watershed in Iran. A flow of data includes three inputs; each of them belongs to one part of three zones of a fluvial system. The three parts of the Sefidrood River fluvial system include Zone 1,a sub-watershed as degradation modeling site,Zone 2,Sefidrood Dam as dam site,and Zone 3,17km away from the Sefidrood River path to the Caspian Sea as ending point site. The degradation model in the Zone 1 provides a suitable mean for decision support system to decrease the human impacts on each small district. The maximum number for degradation coefficient belongs to the small district with the highest physiographic density,relatively cumulative activities,and a lower figure for the habitat vulnerability. The human degradation impact were not limited to the upstream. The investigation to the Sefidrood Dam and ending point of the Sefidrood River depicts that sedimentation continues as a significant visual impact in the Sefidrood Dam reservoir and the estuary.展开更多
Phytoplankton and environmental variables were measured monthly from July 2009 to August 2011 in the Maixi River from the estuary to Baihua Reservoir in the Maotiao River catchment, southwestern China, to understand p...Phytoplankton and environmental variables were measured monthly from July 2009 to August 2011 in the Maixi River from the estuary to Baihua Reservoir in the Maotiao River catchment, southwestern China, to understand phytoplankton community structure and environmental factors. The relationship between phytoplankton community structure and environmental factors including hydrological, meteorological, physical, and chemical variables were explored using multivariate analysis. A total of 81 taxa of phytoplankton were identified, which were mainly composed of chlorophyta, bacillariophyta, and cyanobacteria. The phytoplankton community was dominated by Pseudanabaena limnetica during summer and fall and by Cyclotella meneghiniana during winter and spring. The abundance of phytoplankton ranged from 0.24~ 104 cells/L to 33.45x 106 cells/L, with the minimum occurring during February 2010 and the maximum during July 2009. The phytoplankton community was dominated mainly by cyanobacteria from April to September, and by bacillariophyta and pyrrophyta from October to March. Canonical correspondence analysis showed that temperature, pH values, and orthophosphate were the most important driving factors regulating the composition and dynamics of the phytoplankton community in the estuary. Cyanobacteria and euglenophyta abundance and biomass were affected mainly by temperature and pH values, while most chlorophyta and bacillariophyta were influenced by the concentrations of nutrients.展开更多
基金Funded by the Key Project of International Cooperation of the Natural Science Foundation of China (No. 40721140020)the Key Project of the Natural Science Foundation of China (No. 40730632)
文摘The Huai River Basin is a unique area in P.R.China with the highest densities of population and water projects.It is also subject to the most serious water pollution.We proposed a distributional SWAT(Soil and Water Assessment Tool) model coupled with a water quality-quantity balance model to evaluate dam impacts on river flow regimes and water quality in the middle and upper reaches of the Huai River Basin.We calibrated and validated the SWAT model with data from 29 selected cross-sections in four typical years(1971,1981,1991 and 1999) and used scenario analysis to compensate for the unavailability of historical data regarding uninterrupted river flows before dam and floodgate construction,a problem of prediction for ungauged basins.The results indicate that dam and floodgate operations tended to reduce runoff,decrease peak value and shift peaking time.The contribution of water projects to river water quality deterioration in the concerned river system was between 0 to 40%,while pollutant discharge contributed to 60% to 100% of the water pollution.Pollution control should therefore be the key to the water quality rehabilitation in the Huai River Basin.
文摘The major concern of this article is to address the shortcoming and outgoing effects of the human activities on the landscape patterns and their consequences in the Sefidrood River watershed in Iran. A flow of data includes three inputs; each of them belongs to one part of three zones of a fluvial system. The three parts of the Sefidrood River fluvial system include Zone 1,a sub-watershed as degradation modeling site,Zone 2,Sefidrood Dam as dam site,and Zone 3,17km away from the Sefidrood River path to the Caspian Sea as ending point site. The degradation model in the Zone 1 provides a suitable mean for decision support system to decrease the human impacts on each small district. The maximum number for degradation coefficient belongs to the small district with the highest physiographic density,relatively cumulative activities,and a lower figure for the habitat vulnerability. The human degradation impact were not limited to the upstream. The investigation to the Sefidrood Dam and ending point of the Sefidrood River depicts that sedimentation continues as a significant visual impact in the Sefidrood Dam reservoir and the estuary.
基金Supported by the National Natural Science Foundation of China(No.411063005)the National Basic Research Program of China(973 Program)(No.2012CB426506)the Science and Technology Committee of Guizhou Foundation(Nos.[2011]7028,[2012]7021)
文摘Phytoplankton and environmental variables were measured monthly from July 2009 to August 2011 in the Maixi River from the estuary to Baihua Reservoir in the Maotiao River catchment, southwestern China, to understand phytoplankton community structure and environmental factors. The relationship between phytoplankton community structure and environmental factors including hydrological, meteorological, physical, and chemical variables were explored using multivariate analysis. A total of 81 taxa of phytoplankton were identified, which were mainly composed of chlorophyta, bacillariophyta, and cyanobacteria. The phytoplankton community was dominated by Pseudanabaena limnetica during summer and fall and by Cyclotella meneghiniana during winter and spring. The abundance of phytoplankton ranged from 0.24~ 104 cells/L to 33.45x 106 cells/L, with the minimum occurring during February 2010 and the maximum during July 2009. The phytoplankton community was dominated mainly by cyanobacteria from April to September, and by bacillariophyta and pyrrophyta from October to March. Canonical correspondence analysis showed that temperature, pH values, and orthophosphate were the most important driving factors regulating the composition and dynamics of the phytoplankton community in the estuary. Cyanobacteria and euglenophyta abundance and biomass were affected mainly by temperature and pH values, while most chlorophyta and bacillariophyta were influenced by the concentrations of nutrients.
