Effects of land-use and climate change on sediment and nutrient retention in Guizhou, China

Abstract

Introduction:  Sediment and nutrient retention have significant impacts on agricultural productivity and water quality. Obvious changes of climate and land-use have deeply affected freshwater ecosystem services in the last several decades. Nevertheless, it is unclear what the differences are in the impact of climate and land-use changes on freshwater ecosystem services. Outcomes:  The impacts of climate and land-use change on sediment and nutrient retention (two essential freshwater ecosystem services) were evaluated with the help of the Integrated Valuation of Environmental Services and Tradeoffs (InVEST) model. The results from the study area suggest a decreasing trend in sediment and nutrient retention from 1995 to 2015 when climate and land-use were changed simultaneously. A decreasing trend in sediment retention and an increasing trend in nutrient retention were presented under scenario A (climate change from 1995 to 2015 with land-use unchanged), while the sediment exported and nutrient retention exhibited a decreasing trend except sediment retained under scenario B (land-use change from 1995 to 2015 with unchanged climate). Rainfall erosivity and soil erodibility were more sensitive to the output of sediment retention, while retention efficiency produced more of an effect on nutrient retention. Discussion and Conclusion: Climate change played a dominant role in the change in sediment retention, while land-use change had a more significant effect on nutrient retention change than climate change. The results of this study provide explicitinformation for land-use managers to reduce the negative effects associated with sediment and nutrient retention.