Comparing differences among three ecosystem service proxies for soil erosion prevention and their combination characteristics at local scales

Abstract

The diversity of soil erosion prevention (SEP) indicators may cause the incomparability of different research results. In this study, we first classified the six most commonly used methodological approaches for estimating SEP service into three broad categories. Then, we used the following three indicators: (1) amount of soil conservation (Cs), (2) amount of soil loss (Ls), and (3) the ability of vegetation to prevent soil erosion (Va) as ecosystem service (ES) proxies for SEP. A methodological framework was developed for analyzing the possible relationships between the three SEP indicators and their combination features at local scales to test the validity of the three hypotheses regarding the relationships among these indicators. Afterward, the mountainous area of southern Ningxia was chosen as the experimental area for testing the application of our framework. Results show the following: (1) the hypotheses regarding their associations are only valid under certain conditions when the corresponding indicators can be substituted for each other in the correlation analysis with other ESs; (2) the combinations of Cs, Ls, and Va at local scales are conducive to the discovery of the local soil ecological problems and can help in the formulation of relevant improvement measures. Accordingly, when formulating regional soil conservation measures, we should consider not only the current situation of soil loss but also the trend of climate change. Meanwhile, when analyzing the impact of soil conservation policies, attention should be provided to distinguishing whether the changes in soil loss are due to changes in vegetation cover or potential soil loss.