Water yield service influence by climate and land use change based on InVEST model in the monsoon hilly watershed in South China

Abstract

Based on the data of meteorological, soil, and land use/land cover (LULC), the InVEST model was used to evaluate the water yield service in the middle and upper Ganjiang River region, which is an important ecological function area in the hilly region of South China. This study discusses the value of parameter Z, the impact of climate and LULC change on water yield service, and complements related studies in the monsoon hilly watershed in South China with obvious precipitation change, which is helpful to understand the ecosystem water service functions in this region. The results show that the water yield was closest to the statistical data of total water resources when the parameter Z value of 1.555. The overall distribution of water yield in the MU-GJR was high in the northeast (middle reaches) and low in the southwest (upper reaches), with minimum of 111.8–315.2 mm/a and maximum of 1679.1–2128.4 mm/a from 1980 to 2018. The northeast was a high importance region where high water yield values were clustered, and the southwest was a low importance region where low water yield values were clustered. Water yield was highest in living space and lowest in ecological space. The relationship between land development and water yield service should be coordinated. Climate change had a more significant impact on water yield service than land use change. The results of this study are consistent with the actual situation and help to investigate and identify important areas of water resources in the monsoonal humid zone.