Distribution Characteristics Of Soil Conversation Forest In Northern Shanxi Loess Area

Global change, biodiversity loss and ecological degradation seriously threatens the sustainable development of human society. In this background, China put forward the construction of ecological civilization, our President hu jintao call to develop the forestry enterprise, in2020, the national forest area will add40million hectares. This decision greatly promoted the forestry construction of the loess plateau area. Under the new target, the forest potential of loess plateau region is widely discussed. This article choose shaanxi wuqi county as the research object, using software such as arcGIS, ERDAS, through the analysis of the DEM and remote sensing analysis, quantity, model analysis, analysis the site characteristics of loess area, the vegetation distribution of wuqi county and the distribution of appropriate forest land of wuqi county. These is important for strengthen the construction of local forestry, rational utilization of land resources, and has important guiding significance to the improvement of ecological environment.This paper choose the loess hilly-gully region of the second area, the fifth, deputy area and gully gully region, and the wuqi county as the research object, through the analysis of the DEM elevation such as gradient, slope direction and slope position to analysis the characteristics of the difficult site type. Research shows that,25°to35°slope area ratio is the largest in wuqi county(35.36%of the total area). Dry slope difficult site area reach47.35%, nearly one half of the total area. Poor site conditions put forward higher requirements for wuqi’s ecological forestry construction and configuration of soil and water conservation forest system.The analysis of present landuse situation incluse that, the land use type of wuqi county are mainly forest land and grassland, arable land is complementary (grass88.63%, arable land8.95%). Grass is the main vegetation types, low ecological value vegetation such as low cover grassland has higher proportion in most villages and towns. This land will be the main reformed object of the forestry construction in the future.The best wuqi county forest coverage rate is based on the rainfall erosion prevention. The best forest coverage rate of Wuqi county is50%. The best forest coverage of different afforestation models is different, Seabuckthorn pinus tabulaeformis mixed forests<Seabuckthorn pure forest<acacia pure forest<pure stand of pinus tabulaeformis<seabuckthorn forest of acacia. Based on the optimum forest coverage of wuqi county, vegetation status evaluation showed that lands that don’t reach the protect requirements are main in the northwest of wuqi county, and lands that reach the protect requirements are main in the south of wuqi county, the development of forestry construction of north and south is imbalance.Based on the overlay analysis:the appropriate forest land of wuqi county is total99987.93hectares, including replanting forest land area23225.55hectares and Planting forest land area76762.38hectares. Based on the overlay analysis of soil erosion map, the urgent afforestation land of wuqi county is34749.8hm2,34.8%of the total area, replanting land is10896.9hn2and the planting land is23852.9hm2. II class land has the largest proportion in urgent afforestation land. In the urgent afforestation land of each town, the proportion of I class land are about13%(?)20%, the proportion of II classes land is more than60%, this two parts of land are very important in the future ecological forestry construction.