Abstract: From the perspective of human-land relationship, the study on the impact of typical rural settlements on the ecological environment is of great strategic significance for rationally optimizing the distribution pattern of rural settlements and ensuring food security. Taking Keshan County, a typical black soil region in Northeast China, as an example, spatial analysis methods such as dispersion statistics, kernel density estimation, and spatial correlation measurement models were comprehensively used to explore and reveal the spatiotemporal evolution of rural settlements in Keshan County from 1988 to 2018. The influences of rural settlement distribution characteristics on soil erosion are explored by the landscape index analysis and the gray relational degree quantification model of the generalized variation coefficient based on the RULSE model. The results show that:(1) In the past 30 years, the number of rural settlement areas in Keshan County has increased sharply, and the trend of decentralization is obvious. The spatial distribution is characterized by "high-density multicore agglomeration, low-density widespread distribution", and the distribution center of gravity has migrated to the northeast. (2) The soil erosion is mainly at micro light and moderate level, and the spatial distribution pattern of soil erosion intensity is consistent with the spatial distribution pattern of rural residential areas. (3) The distribution characteristic factors of rural settlement areas have different effects on soil erosion. The distribution range and density of rural settlement areas have a strong relationship with soil erosion.

Key words: typical black soil region of Northeast China, rural settlement, spatio-temporal evolution, soil erosion, coupling relationship, Keshan County