| Hunshandak Sandland, in the northern China, has been investigated and found seriously degradation in the population, community and landscape levels. By applying the principle of "conserving grassland by growing forage", it is found that establishing of nature reserve can restore the degraded ecosystem in Hunshandak Sandland, as well as keep economic development. 1) The elm (Ulmus pumila L.) population is declining in number and in age. The study indicates that middle and old individuals accounting for more than 60% in the population, young individuals is seldom found. Using the method of once-average-process to forecast the number of every age class in elm population, it is found that the number of aged individuals will increase and that of young or middle age individuals will decrease in the next 20, 40, 60 and 100 years. At present, the most individuals in the elm population have strong capability to reproduce, thus, the population might rebirth by itself under protection. In order to restore elm population, the population should be protected, and heavy grazing or felling should be banned. 2) It is found that the plant community in a fixed sandy dune is composed of communities of sunny slope, shady slope, sandy dune chine, sandy dune waist, sandy dune winded pit, sand sediment slope and top of dune. Community in shady slope has the characteristics with rich in plant species, low density and uniformity in plant distribution. The community can be categorized as shaded woody tree, semi-woody + willow shrub grass. The community in sunny slope is mainly composed of Artemisia intramongolica, Bassia dasyphylla and Corispermum heptapotamicum, simple in species composition, high in density and uneven in distribution. The community in chine of dune is Artemisia intramongolica + semi-dryland grasses, that in dune waist is Hedysarum fruticosum + subshrub + semi-dryland grasses. Corispermum heptapotamicum and Setaria viridis dominant in the community of sand sediment slope, Artemisia intramongolica, Corispermum heptapotamicum and Setaria viridis dominant in the community of winded pit, Corispermum heptapotamicum community is developing in the top of sandy dune. 3) There are many patches of Ulmus pumila sparse forest distributed in the Hunshandak Sandland. It's found that the sparse forest patches are mainly distributed in 20 villages regions, with average 0.96 km2 for each patch. For these 20 villages, the patch density ranges from 0.10 to 0.24 km-2, the edge density ranges from2.50 to 12.50 km-1, and separating degrees ranges from 0.4 to 1.20 km, these indexes showed that the fragmentation of sparse-forest is serious, and need to be protected. 4) Degraded ecosystem in Hunshandak Sandland can be restored through nature reserve. By applying the principle of "nutrition land by land itself", an experimental natural grassland recovery site set up in Bayinhushu Village, Herisitai Sum, Zhenglan Banner. The results showed that biomass, height and coverage of community in various habitats have been significantly increased after two years protection (P<0.05). Although this experiment reports the results of a demonstration project in one small village, it has encouraged Banner officials to begin a concerted effort to establish a nature reserve in the entire Zhenglan Banner. 5) In order to protect the landscape of Ulmus pumila sparse forest, a nature reserve is planned to construct in Hunshandak Sandland. Based on the principles of island biogeography theory and landscape ecology theory, using the ArcGIS software, the planed nature reserve is primarily determined. 6) The sustainable development of Hunshandak Sandland region. In the light of sustainable development theory, the subsystems of environment, economy and society in every Sum/town have been appraised. Under the appraising scores, Hunshandak Sandland region can be categorized into four districts in order to employ fit polices for sustainable development.
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