Land use change and its eco-enviromnental effects in transitional agro-pastoral region - the case study of Yulin district in northern Shaanxi

The farming and grazing interlocked transitional zone along the Great Wall in northern Shaanxi Province is particularly vulnerable to desertification due to its fragile ecosystem and intensive human activities there. Based on the TM data of land use/land cover in Yulin district, Shaaxi Province, the process of land use transformation and associated contribution to the regional eco-environment in Yulin were measured and quantified spatial-explicitly, the main results and finding include that: 1) the land use pattern had a large change in the last 15 years; 2) the general quality of regional eco-environment has improved over the last 1.5 years. However, the trends of both improvement and degradation in eco-environment were coexist, and displayed their spatial heterogeneity in county-level; 3) wind-sand areas in north has a better improvement in eco-environment than that of hilly-donga in south; 4) tree planting and forestation have the most distribution to the improvement of eco-environment, its distribution ratio 74.8%.