Spatial-temporal Variation of Water Yield in Nanbei Panjiang River Basin Based on InVEST Model

Abstract

[Objective] The temporal and spatial variation characteristics of water yield and differences in the water yield function for different land use types, soil types, and topography in the Nanbei Panjiang River basin were analyzed in order to provide a scientific reference for the effective management of water resources and ecological restoration in the basin. [Methods] The spatial and temporal variation characteristics, internal differences, and the influence of vegetation restoration on the water yield function in the Nanbei Panjiang River basin from 2005 to 2020 were quantitatively evaluated using the InVEST model. [Results] The average total water yield in the basin fluctuated slightly from 2005 to 2020, showing a trend of higher in the northeast and central regions and lower in the southwest. The overall water yield pattern was spatially consistent with the spatial and temporal changes of precipitation. Without considering the significant change of rainfall, the decrease of cultivated land and grassland areas was the main reason for the slight fluctuation and downward trend of total water yield in the basin. The land use type with the strongest water yield capacity was construction land, followed by bare land, cultivated land, and grassland. The water yield capacities of evergreen coniferous forest and shrub land were weak. The water yield capacity in the basin gradually decreased with increasing altitude, and the soils with strong water yield capacity were mainly yellow soil and red soil. The high water yield areas in the basin were mainly concentrated in the northeast and central regions having low and medium altitudes, and were mainly yellow soil and red soil. The low value area was mainly concentrated in the southwest region having high and higher altitudes with large amounts of lime (rock ) soil and purple soil. [Conclusion] The spatial pattern of water yield in the basin exhibited some changes, and the high value area of water yield had a tendency to shift to the east and northeast. Land use type, meteorological factors, soil texture, topography, and other factors have an important impact on the spatial heterogeneity of the water yield function.

Keywords

• ecosystem services
• nanbei panjiang river basin
• invest model
• water yield
• temporal and spatial variation characteristics