Spatio-temporal changes in ecosystem service bundles and hotspots in Beressa watershed of the Ethiopian highlands: Implications for landscape management

Abstract

Assessment of the change in ecosystem services and their bundles and hotspots in a spatial-explicitly manner can provide practical support for ecological conservation measure priority setting. This study assessed the spatio-temporal dynamics of vital ecosystem services (ESs) from 1972 to 2047 and identified statistically significant hotspots and coldspots of ES clusters in the Beressa watershed using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model and spatial statistical analysis. The result showed that the provision of ESs significantly declined over the study period. Habitat maintenance, sediment retention, and water retention were spatially co-occurring, while the service of climate regulation and crop yield showed a reasonable difference in their distribution. Consequently, spatial and temporal correlations within hydrological regulating services and habitat maintenance were consistent, however the relationship between crop yield and regulating services varied with time. The result of spatial clustering indicated that bundle 1 and 2 had high hydrological and allied services due to a high proportion of grassland, clustered in western areas with lower elevation and relatively gentle slope. Bundle 3 with high agricultural provisioning showed various distribution during the study period. Bundle 4 had increased climate regulation clustered in eastern areas in high elevation and steep slope land and holds a high proportion of plantation. On average, hotspot and coldspot comprised about 24% and 48% of the space, respectively. Hotspots delivered most ESs, and their area declined, while coldspots increased during the study period. The spatio-temporal variations in ESs appeared to be determined by human activities, especially expansion of artificial plantation, human settlements, agricultural practice, and topographic gradient. ES bundles and hotspots analyses can identify areas in the landscape whereby ecosystem management has produced maximum benefits through enhancing services. Therefore, landscape preference should be integrated into land management plans to amend ecosystem's function.