The study of snow and ice melt （SIM） is important in water-scarce arid regions for the assessment of water supply and quality. These studies involve unique difficulties, especially in the calibration of hydro-models...The study of snow and ice melt （SIM） is important in water-scarce arid regions for the assessment of water supply and quality. These studies involve unique difficulties, especially in the calibration of hydro-models because there is no direct way to continuously measure the SIM at hydrostations. The recursive digital filter （RDF） and the isotopic hydro-geochemical method （IHM） were coupled to separate the SIM from eight observed series of alpine streamflows in northwestern China. Validation of the calibrated methods suggested a good capture of the SIM characteristics with fair accuracy in both space and time. Applications of the coupled methods in the upper reaches of the Hei River Basin （HRB） suggested a double peak curve of the SIM fraction to streamflow for the multi-component recharged （MCR） rivers, while a single peak curve was suggested for the rainfall-dominant recharged （RDR） rivers. Given inter-annual statistics of the separation, both types of the alpine rivers have experienced an obvious decrease of SIM since 196os. In the past 10 years, the SIM in the two types of rivers has risen to the levels of the 1970s, but has remained lower than the level of the 1960s. The study provided a considerable evidence to quantify the alpine SIMbased on the separation of observed data series at gauge stations. Application of the coupled method could be helpful in the calibration and validation of SIM-related hydro-models in alpine regions.展开更多
This paper reviewed the existing methods in regionalization studies to predict ungauged catchments and considering all the aspects a different methodology is developed, which is named as RDS method. ROPE （robust para...This paper reviewed the existing methods in regionalization studies to predict ungauged catchments and considering all the aspects a different methodology is developed, which is named as RDS method. ROPE （robust parameter estimation）-D （data depth）-S （spatial proximity） together gets this name RDS. Catchment properties and hydrological model parameters are used consistently to predict ungauged basin. This study explores the potential of the regionalization process to predict ungauged basins using the data of the Eastern USA catchments. Two conceptual rainfall-runoff hydrological models： HYMOD and HBV are used in this study. Analysis shows 95% success in predicting ungauged basins with HBV and 90% success with HYMOD. It is undoubtedly perceptible that RDS method is very effective in predicting ungauged basin and regionalization is independent of the conceptual rainfall-runoff model.展开更多
The history of the formation and development of Chinese civilization is also a civilization history of water conservancy. Water not only gives birth to Chinese civilization but also gives birth to the unique regional ...The history of the formation and development of Chinese civilization is also a civilization history of water conservancy. Water not only gives birth to Chinese civilization but also gives birth to the unique regional culture in Lingnan. In the past thousands of year, from the ancient myths and legends of Lingnan water conservancy culture to the digging of efficacious Canal＇s integration of the nationalities in Lingnan, to the blending of water and culture of the Xijiang River and the North River of the Zhujiang water system and the formation of urban river culture, development of its generation, deduction and inheritance has the mutual penetration with the formation of water system and the variation of water conservancy which mutually influence the historical evolvement of Lingnan regional culture.展开更多
Whether mining activity results in reduced flow of surface water in the Peace River Watershed of Florida has been the subject of much debate. With increased dependence of downstream users on surface water flow of the ...Whether mining activity results in reduced flow of surface water in the Peace River Watershed of Florida has been the subject of much debate. With increased dependence of downstream users on surface water flow of the Peace River as a source of drinking water for four coastal counties in Southwest Florida and problems of water security, the debate has been intensified. It is possible to assess relationships of mining with streamflow in the upper reaches of the Peace River Basin using hydrologic modeling and identify mined sub-basins. In this work, land-use change impacts were simulated by the Hydrological Simulation Program--Fortran （HSPF） model based on geographical information system （GIS） tools, to compare pre- and post-mining streamflows at a study site of the Peace River in west-central Florida. The purpose of this study was to determine if land-use changes caused by mining have negatively impacted streamflow in the Peace River. Changes of land use were identified before and after mining activities. A coupled volume-water depth-discharge （V-h-Q） model based on stage/storage and stage/discharge was applied using HSPF for the pre-mining and post-mining models, respectively. Daily simulated post-mining hydrographs from HSPF were plotted with the calibrated pre-mining results and streamflow hydrographs from the 18 gauging stations, to compare timing of peaks, low fows and flow trends. Analyses of percent ex- ceedances of flow frequency curves of the streams indicated that most streams had similar distributions for mined （reclaimed） and pre- mining periods. In the streamflow change analysis, streamflows actually increased in mining-affected basins at nearly half the stations. Streamflows at other stations diminished. Overall from this comprehensive study, there were declines in streamflow at most gauging stations on the mainstem of the Peace River and its tributaries. The results of this study suggest that regional planning is urgently needed to propose reclamation schemes that enhance regional hydrology.展开更多
To determine whether reforestation efforts in the denuded hills have significant impacts on hydrology in the Xinjiang River watershed, the authors examined eight land-cover scenarios to compare hydrologic responses an...To determine whether reforestation efforts in the denuded hills have significant impacts on hydrology in the Xinjiang River watershed, the authors examined eight land-cover scenarios to compare hydrologic responses and to provide a conceptual basis for restoration practices. The authors analyzed a 17-year time period using remote sensing to develop land-cover classification for the watershed. Climate, soil and terrain data for the watershed were used as input in the SWAT （soil and water analysis tool） to quantify and compare the impacts on hydrologic processes. The model was calibrated to a two-year record of stream discharge measurements. The results show significant increase in forest-cover on hills （13%）. However, the hydrological response is not very significant considering the changes in forest-cover, the surface runoff and percolation ratios only changed by 2% and 1% over time. Installment of earthen irrigation ponds in the outlets of sub-basin with maximum runoff had provided the most significant hydrologic improvements and could provide irrigation water to increase crop yield on remaining cropland. The study will provide information to the local government to aid decision-making in sustainable reforestation programs resulting in better hydrologic functioning for sustainable water resource management.展开更多
基金supported by the following grants:National Key Research and Development Program of China (Grant No. 2009CB421306)the NSFC Project (Grant Nos. 41001014, 51209119) NSFC Projects (Grant Nos. 41240002, 91225301)+1 种基金the NSFC Key Project (Grant No. 91125010)the MAIRS Project funded by the NASA LCLUC Program (Grant No. NNX08AH50G)
文摘The study of snow and ice melt （SIM） is important in water-scarce arid regions for the assessment of water supply and quality. These studies involve unique difficulties, especially in the calibration of hydro-models because there is no direct way to continuously measure the SIM at hydrostations. The recursive digital filter （RDF） and the isotopic hydro-geochemical method （IHM） were coupled to separate the SIM from eight observed series of alpine streamflows in northwestern China. Validation of the calibrated methods suggested a good capture of the SIM characteristics with fair accuracy in both space and time. Applications of the coupled methods in the upper reaches of the Hei River Basin （HRB） suggested a double peak curve of the SIM fraction to streamflow for the multi-component recharged （MCR） rivers, while a single peak curve was suggested for the rainfall-dominant recharged （RDR） rivers. Given inter-annual statistics of the separation, both types of the alpine rivers have experienced an obvious decrease of SIM since 196os. In the past 10 years, the SIM in the two types of rivers has risen to the levels of the 1970s, but has remained lower than the level of the 1960s. The study provided a considerable evidence to quantify the alpine SIMbased on the separation of observed data series at gauge stations. Application of the coupled method could be helpful in the calibration and validation of SIM-related hydro-models in alpine regions.
文摘This paper reviewed the existing methods in regionalization studies to predict ungauged catchments and considering all the aspects a different methodology is developed, which is named as RDS method. ROPE （robust parameter estimation）-D （data depth）-S （spatial proximity） together gets this name RDS. Catchment properties and hydrological model parameters are used consistently to predict ungauged basin. This study explores the potential of the regionalization process to predict ungauged basins using the data of the Eastern USA catchments. Two conceptual rainfall-runoff hydrological models： HYMOD and HBV are used in this study. Analysis shows 95% success in predicting ungauged basins with HBV and 90% success with HYMOD. It is undoubtedly perceptible that RDS method is very effective in predicting ungauged basin and regionalization is independent of the conceptual rainfall-runoff model.
文摘The history of the formation and development of Chinese civilization is also a civilization history of water conservancy. Water not only gives birth to Chinese civilization but also gives birth to the unique regional culture in Lingnan. In the past thousands of year, from the ancient myths and legends of Lingnan water conservancy culture to the digging of efficacious Canal＇s integration of the nationalities in Lingnan, to the blending of water and culture of the Xijiang River and the North River of the Zhujiang water system and the formation of urban river culture, development of its generation, deduction and inheritance has the mutual penetration with the formation of water system and the variation of water conservancy which mutually influence the historical evolvement of Lingnan regional culture.
基金National Natural Science Foundation of China(No.41271004)Beijing Municipal Science &Technology New Star Project Funds(No.2010B046)
文摘Whether mining activity results in reduced flow of surface water in the Peace River Watershed of Florida has been the subject of much debate. With increased dependence of downstream users on surface water flow of the Peace River as a source of drinking water for four coastal counties in Southwest Florida and problems of water security, the debate has been intensified. It is possible to assess relationships of mining with streamflow in the upper reaches of the Peace River Basin using hydrologic modeling and identify mined sub-basins. In this work, land-use change impacts were simulated by the Hydrological Simulation Program--Fortran （HSPF） model based on geographical information system （GIS） tools, to compare pre- and post-mining streamflows at a study site of the Peace River in west-central Florida. The purpose of this study was to determine if land-use changes caused by mining have negatively impacted streamflow in the Peace River. Changes of land use were identified before and after mining activities. A coupled volume-water depth-discharge （V-h-Q） model based on stage/storage and stage/discharge was applied using HSPF for the pre-mining and post-mining models, respectively. Daily simulated post-mining hydrographs from HSPF were plotted with the calibrated pre-mining results and streamflow hydrographs from the 18 gauging stations, to compare timing of peaks, low fows and flow trends. Analyses of percent ex- ceedances of flow frequency curves of the streams indicated that most streams had similar distributions for mined （reclaimed） and pre- mining periods. In the streamflow change analysis, streamflows actually increased in mining-affected basins at nearly half the stations. Streamflows at other stations diminished. Overall from this comprehensive study, there were declines in streamflow at most gauging stations on the mainstem of the Peace River and its tributaries. The results of this study suggest that regional planning is urgently needed to propose reclamation schemes that enhance regional hydrology.
文摘To determine whether reforestation efforts in the denuded hills have significant impacts on hydrology in the Xinjiang River watershed, the authors examined eight land-cover scenarios to compare hydrologic responses and to provide a conceptual basis for restoration practices. The authors analyzed a 17-year time period using remote sensing to develop land-cover classification for the watershed. Climate, soil and terrain data for the watershed were used as input in the SWAT （soil and water analysis tool） to quantify and compare the impacts on hydrologic processes. The model was calibrated to a two-year record of stream discharge measurements. The results show significant increase in forest-cover on hills （13%）. However, the hydrological response is not very significant considering the changes in forest-cover, the surface runoff and percolation ratios only changed by 2% and 1% over time. Installment of earthen irrigation ponds in the outlets of sub-basin with maximum runoff had provided the most significant hydrologic improvements and could provide irrigation water to increase crop yield on remaining cropland. The study will provide information to the local government to aid decision-making in sustainable reforestation programs resulting in better hydrologic functioning for sustainable water resource management.
