Using a settlement connectivity-based framework to map the farmland abandonment risk: A case study on the World Heritage of Honghe Hani Rice Terraces

Farmland abandonment is a gradual, complex, and fragmented process that varied with time and space. How to identify the abandonment-risk of farmland with a spatial explicit way is a challenge and a key step toward the efficient management and sustainability of regional agriculture. This paper introduced the quantification method of connectivity from landscape ecology, took the rural settlements as the source patches that farmers moved out with materials and energies into the sink patches of farmlands, and during the moving process the least-cost path among settlements means the highest connectivity and the lowest risk of farmland abandonment. Then the new integrated framework for spatially quantifying the abandonment-risk of farmland based on settlement connectivity combined with the least-cost model (namely the FARBSC framework) was put forward and validated at the Honghe Hani Rice Terraces (HHRT) in Southwestern China. The verification and accuracy comparison of the FARBSC framework to the composite indicators and the buffer zone analysis of settlement were all indicated the efficiency of the new method. For the HHRT region, according to the FARBSC framework, the risky, weakly stable, stable, and highly stable zone is occupied 13.5%, 43.3%, 36.7%, and 6.5% of the land, respectively. The FARBSC framework had provided a quick and convenient way to mapping the risk area of farmland abandonment, especially for data-lack remote rural mountainous areas, such rice terrace heritage sites in mountainous Asia. More detailed spatial data can be used to improve its accuracy in future studies.