Spatio-temporal process of unused land resources in China and its ecological effects

Unused land has changed rapidly over the past 30 years, resulting in its ecological environment changes as well. The mathematical methodology, which includes dynamic degree index model, spatial density model, change intensity model, conversion matrix, and index model of ecological effects, was developed for studying spatial pattern changes of unused land and the ecological effect caused by unused land change. Based on these models, spatial-temporal process of unused land was calculated and analyzed, and eco-environment change caused by unused land change was evaluated. The results show that unused land area continued to decrease, and the general quality of regional eco-environment caused by unused land change has deteriorated during the study period.