![]() The main purposes of this study are to estimate how the streamflow and sediment yields will change under different climate change scenarios in different future periods and whether these changes in streamflow and sediment will be different in watersheds with different land use cover in the Loess Plateau. ![]() The effects of climate changes on hydrological and sedimental processes in different watersheds were estimated and compared. A series of scenario analyses were, respectively, achieved in a cultivated land and grass-dominant watershed and in a woodland-dominant watershed. In this study, two typical upland watersheds with different land-use cover conditions in the Loess Plateau were considered. Thus, quantitative estimations of hydrological and sedimentary processes in response to future climate change in watersheds with different landscapes in the Yellow River Basin are significant to local management for better mitigation strategies and more efficient management practices. The hotter and wetter climate status may lead to various possible changes in streamflow and sediment yields in different areas with different underlying surface conditions. However, such profits are being challenged and may be offset by future climate change. The sediment load on the Loess Plateau has decreased in the past few decades due to various conservation projects, such as increasing vegetation coverage and terrace construction. Excessive sediment yields reveal significant environmental threats to riverbed routes and aquatic ecosystems, for which effective control measures are needed. A large amount of sediments are discharged into the middle stream of the Yellow River due to the substantial erosions taking place in the Chinese Loess Plateau. The Yellow River, as the second longest river in China and the sixth longest river system in the world, is one of the most sediment-laden rivers in the world. However, different areas possibly have different aspects of response behavior, and it is necessary to carry out case studies in critical areas. Many studies have evaluated the response of runoff and sediment loading to climate and land use/land cover change, based on historical data and/or various modeling tools. In addition, differences in underlying surface conditions in different watersheds would lead to high uncertainties in the extent and magnitude of these variations. Temperature and precipitation changes in future climate change are expected to greatly affect the available water in the basin, so as to alter original soil loss and sediment delivery characteristics. The sediment transport is driven by watershed hydrological processes, which are determined by the watershed land use cover and weather conditions for both precipitation and temperature. Among them, soil erosion mainly depends on the basic conditions such as the amount and intensity of precipitation as well as the land use cover of the watershed. Soil erosion and subsequent sediment transport is the main source of suspended sediment in riverine systems. The sediment substance in water bodies is of great importance for the aquatic ecosystem. ![]() The multi-model approach proposed in this study had reliable performance and could be applied in other similar areas with modest data conditions. The peak of sediment would appear in the 2050s, and integrated measures for sediment control should be implemented to reduce erosion and block delivery. Increased erosion and sediment yields could be found in the study area, with lesser increments in sediment in woodland than in cultivated field. The results showed that there would be generally hotter and wetter weather conditions in the future. The Generalized Watershed Loading Functions (GWLF) model was employed to model the streamflow and sediment yields under various scenarios and periods. The Long Ashton Research Station Weather Generator (LARS-WG) was employed to downscale the outputs of GCMs for future site-scale daily weather data estimations. ![]() The outputs of eleven Global Climate Models (GCMs) were used to represent the future climate status of the 2050s and 2070s, and an ensemble means was achieved to avoid uncertainty. Four Representative Concentration Pathway (RCP) scenarios with different radiative forcing levels were considered. The responses of hydrological and sedimental processes to future climate change in two upland watersheds with different dominant landscapes were estimated. This study concerned the sediment issue of the Yellow River basin. ![]()
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