Analysis of spatial and temporal changes of regional ecological pattern in the northwest of Jingjinji as water conservation area during the past 30 years

In this study, we aimed to understand the status and changes in ecological and landscape patterns for each ecosystem in the northwest water conservation area of Jingjinji, China. Spatial distribution maps of the ecosystems in three phases were produced using land cover data from 1987, 2000 and 2015, and these were analyzed using a land transfer matrix. The landscape pattern of 19 ecosystem categories at a scale of the entire study area and six major ecosystems at county scales were analyzed using a landscape pattern index. The results show that the main ecosystem changes in this region were owing to the conversion of farmland into forest and settlement, alongside the conversion of grassland and wetland into farmland. Forests and settlements increased by 4 511.65 (0.56%) and 34 264.81 ha^–1 (42.21%) , respectively, while grasslands, farmlands, and wetlands decreased by 23 572.20 (2.37%), 8518.98 (0.47%) and 6 747.53 ha^–1 (4.33%) , respectively. The pressure of forest growth and urbanization expansions transformed grasslands and wetlands. The original grassland and wetland ecosystems have been destroyed by artificial expansion and the evolution of settlements and farmlands, resulting in fragmentation and diversification of the landscape patterns in the region.