Sixty springs of the Cuneo Province inland plains were sampled and analyzed for several chemical variables. Multi-variate analysis （PCA） of all the data was undertaken. The first principal component was positively c...Sixty springs of the Cuneo Province inland plains were sampled and analyzed for several chemical variables. Multi-variate analysis （PCA） of all the data was undertaken. The first principal component was positively correlated with chlorides, sulphites, hardness, and negatively correlated with altitude. The second principal component was positively correlated with DO and pH. Results showed that 4 groups of springs could be distinguished on the basis of environmental variables. A small number of springs did not group with the geographically more proximal springs but with another group due to a greater degree of affinity on the basis of the hydrochemical variables.展开更多
Using eight years of time-variant gravity measurements from the GRACE gravity satellite mission, we estimate monthly terrestrial water storage variations in the North China Plain between August 2002 and August 2010. W...Using eight years of time-variant gravity measurements from the GRACE gravity satellite mission, we estimate monthly terrestrial water storage variations in the North China Plain between August 2002 and August 2010. We find that during this period, the water storage is not constant but accelerate at a rate of -1.1 cm/yr over time. The study confirms that the relatively long-term trend of water storage in the North China Plain (by 13-point moving average) is consistent well with that by linear fitting. Two hydrological models, CPC and GLDAS, are adopted in calculating surface water variations, with results indicating that they agree with those of GRACE. Furthermore, rates of -0.6 cm/yr for surface water variations and -0.5 cm/yr for groundwater variations are found in the North China Plain during the study period. Decrease of rainfall and the groundwater over-exploitation are possibly the main causes for groundwater depletion in the North China Plain. The results will be helpful for better understanding climatic changes and provide reference for the management of water resources and the establishment of policies on preventing and alleviating natural hazards.展开更多
文摘Sixty springs of the Cuneo Province inland plains were sampled and analyzed for several chemical variables. Multi-variate analysis （PCA） of all the data was undertaken. The first principal component was positively correlated with chlorides, sulphites, hardness, and negatively correlated with altitude. The second principal component was positively correlated with DO and pH. Results showed that 4 groups of springs could be distinguished on the basis of environmental variables. A small number of springs did not group with the geographically more proximal springs but with another group due to a greater degree of affinity on the basis of the hydrochemical variables.
基金supported by National High Technology Program of China (Grant No. 2010AA12206)National Natural Science Foundation of China (Grant No. 10973031)
文摘Using eight years of time-variant gravity measurements from the GRACE gravity satellite mission, we estimate monthly terrestrial water storage variations in the North China Plain between August 2002 and August 2010. We find that during this period, the water storage is not constant but accelerate at a rate of -1.1 cm/yr over time. The study confirms that the relatively long-term trend of water storage in the North China Plain (by 13-point moving average) is consistent well with that by linear fitting. Two hydrological models, CPC and GLDAS, are adopted in calculating surface water variations, with results indicating that they agree with those of GRACE. Furthermore, rates of -0.6 cm/yr for surface water variations and -0.5 cm/yr for groundwater variations are found in the North China Plain during the study period. Decrease of rainfall and the groundwater over-exploitation are possibly the main causes for groundwater depletion in the North China Plain. The results will be helpful for better understanding climatic changes and provide reference for the management of water resources and the establishment of policies on preventing and alleviating natural hazards.
