Spatial Heterogeneity and Fragmentation Trends of Ecosystem Services: The Case of Highland Watershed

Abstract

Landscape fragmentation and heterogeneity are poorly understood and acknowledged in the Ethiopian highlands. Land fragmentation has both direct and indirect relationship with productivity, water resource, sediment load and enviorment. This study aims to spatially characterize the state of heterogeneity and fragmentation of ecosystem services (ES) since 1957. The data were obtained from the aerial photograph and field data. Indices were used to analyse fragmentation and heterogeneity. A total of 1869 parcels were mapped using GPS. Average crop landholding size and number of parcels per household was 0.18 ha and 4.5, respectively. The density of cropland was 150 parcels/100 ha and of shrubland was one parcel/100ha. The highest number, density, dominance and smallest size were revealed for food providing land parcels. However, cultural service providing parcels are larger in size. The increase of demand and the different use rights for ESs caused to increase the heterogeneity of the land cover types. The analyses indicated that there has been an increasing trend of land fragmentation. Such condition deteriorates productivity of the resource base and diminishes benefits from the ESs. The study recommends research and policy tools (such as clustering similar land units) to limit further fragmentation and calls for more work on how fragmentation affects productivity, water, environment and land management decisions.