Satellite-based products with high spatial and temporal resolution provide useful precipitation information for data-sparse or ungauged large-scale watersheds. In the Lower Lancang-Mekong River Basin, rainfall station...Satellite-based products with high spatial and temporal resolution provide useful precipitation information for data-sparse or ungauged large-scale watersheds. In the Lower Lancang-Mekong River Basin, rainfall stations are sparse and unevenly distributed, and the transboundary characteristic makes the collection of precipitation data more difficult, which has restricted hydrological processes simulation. In this study, daily precipitation data from four datasets(gauge observations, inverse distance weighted(IDW) data, Tropical Rainfall Measuring Mission(TRMM) estimates, and Climate Hazards Group InfraRed Precipitation with Stations(CHIRPS) estimates), were applied to drive the Soil and Water Assessment Tool(SWAT) model, and then their capability for hydrological simulation in the Lower Lancang-Mekong River Basin were examined. TRMM and CHIRPS data showed good performances on precipitation estimation in the Lower Lancang-Mekong River Basin, with the better performance for TRMM product. The Nash-Sutcliffe efficiency(NSE) values of gauge, IDW, TRMM, and CHIRPS simulations during the calibration period were 0.87, 0.86, 0.95, and 0.93 for monthly flow, respectively, and those for daily flow were 0.75, 0.77, 0.86, and 0.84, respectively. TRMM and CHIRPS data were superior to rain gauge and IDW data for driving the hydrological model, and TRMM data produced the best simulation performance. Satellite-based precipitation estimates could be suitable data sources when simulating hydrological processes for large data-poor or ungauged watersheds, especially in international river basins for which precipitation observations are difficult to collect. CHIRPS data provide long precipitation time series from 1981 to near present and thus could be used as an alternative precipitation input for hydrological simulation, especially for the period without TRMM data. For satellite-based precipitation products, the differences in the occurrence frequencies and amounts of precipitation with different intensities would affect simulation results of water balance components, which should be comprehensively considered in water resources estimation and planning.展开更多
The Lancnag Mekong River is the most important international river across China and Southeast Asia, If it is developed according to 'Great Mekong Subregional Cooperation Plan' [9] prepared by ADB, the area di...The Lancnag Mekong River is the most important international river across China and Southeast Asia, If it is developed according to 'Great Mekong Subregional Cooperation Plan' [9] prepared by ADB, the area directly affected will be up to over 2.32 million km 2, the population over 220 million, and the natural environment, and socio-economic conditions within a large area will be greatly changed. 'Agreement on Cooperation for Sustainable Development of Mekong Basin' signed by the four riparian countries along the lower Mekong River on April 5, 1995 provides a new opportunity for sustainable development of the Basin. According to preliminary analysis, if the multipurpose utilization of the water resources is the target for carrying out integrated planning and management, and the efforts are made 1) to focus on energy exploitation on the Lancang River Mainstream and the tributaries of the lower Mekong River; 2) to build gated weirs at Tonle Sam; 3) to construct spillways at the Mekong Delta; 4) to facilitate flood dykes in big cities and on both banks of the mainstream which are concentrated with population and farmland and liable to be flooded, and 5) to strengthen networks for forecasting hydrological and meteorological conditions, then all problems such as power demand, irrigation, flood, salt water intrusion as well as acid water erosion to soil could be solved without constructing large cascaded stations and dams on the lower Mekong Mainstream. This will not only avoid input of great number of fund, large scale resettlement and land inundation, but also prevent aquatic organisms living in Mekong River from being injured due to dam construction, and promote the sustainable development of the Basin.展开更多
基金National Key R&D Program of China(No.2016YFA0601601)National Natural Science Foundation of China(No.41601026,41661099)Science and Technology Planning Project of Yunnan Province,China(No.2017FB073)
文摘Satellite-based products with high spatial and temporal resolution provide useful precipitation information for data-sparse or ungauged large-scale watersheds. In the Lower Lancang-Mekong River Basin, rainfall stations are sparse and unevenly distributed, and the transboundary characteristic makes the collection of precipitation data more difficult, which has restricted hydrological processes simulation. In this study, daily precipitation data from four datasets(gauge observations, inverse distance weighted(IDW) data, Tropical Rainfall Measuring Mission(TRMM) estimates, and Climate Hazards Group InfraRed Precipitation with Stations(CHIRPS) estimates), were applied to drive the Soil and Water Assessment Tool(SWAT) model, and then their capability for hydrological simulation in the Lower Lancang-Mekong River Basin were examined. TRMM and CHIRPS data showed good performances on precipitation estimation in the Lower Lancang-Mekong River Basin, with the better performance for TRMM product. The Nash-Sutcliffe efficiency(NSE) values of gauge, IDW, TRMM, and CHIRPS simulations during the calibration period were 0.87, 0.86, 0.95, and 0.93 for monthly flow, respectively, and those for daily flow were 0.75, 0.77, 0.86, and 0.84, respectively. TRMM and CHIRPS data were superior to rain gauge and IDW data for driving the hydrological model, and TRMM data produced the best simulation performance. Satellite-based precipitation estimates could be suitable data sources when simulating hydrological processes for large data-poor or ungauged watersheds, especially in international river basins for which precipitation observations are difficult to collect. CHIRPS data provide long precipitation time series from 1981 to near present and thus could be used as an alternative precipitation input for hydrological simulation, especially for the period without TRMM data. For satellite-based precipitation products, the differences in the occurrence frequencies and amounts of precipitation with different intensities would affect simulation results of water balance components, which should be comprehensively considered in water resources estimation and planning.
文摘The Lancnag Mekong River is the most important international river across China and Southeast Asia, If it is developed according to 'Great Mekong Subregional Cooperation Plan' [9] prepared by ADB, the area directly affected will be up to over 2.32 million km 2, the population over 220 million, and the natural environment, and socio-economic conditions within a large area will be greatly changed. 'Agreement on Cooperation for Sustainable Development of Mekong Basin' signed by the four riparian countries along the lower Mekong River on April 5, 1995 provides a new opportunity for sustainable development of the Basin. According to preliminary analysis, if the multipurpose utilization of the water resources is the target for carrying out integrated planning and management, and the efforts are made 1) to focus on energy exploitation on the Lancang River Mainstream and the tributaries of the lower Mekong River; 2) to build gated weirs at Tonle Sam; 3) to construct spillways at the Mekong Delta; 4) to facilitate flood dykes in big cities and on both banks of the mainstream which are concentrated with population and farmland and liable to be flooded, and 5) to strengthen networks for forecasting hydrological and meteorological conditions, then all problems such as power demand, irrigation, flood, salt water intrusion as well as acid water erosion to soil could be solved without constructing large cascaded stations and dams on the lower Mekong Mainstream. This will not only avoid input of great number of fund, large scale resettlement and land inundation, but also prevent aquatic organisms living in Mekong River from being injured due to dam construction, and promote the sustainable development of the Basin.
