Study on Forest Type/Tree Species Structure Optimization of Yanchi Sandy Area Eco-economical Shelterbelt System in Ningxia

Structure analysis was used to analyze the present situation of forestry construction of Yanchi sandy area in Ningxia.The optimized model for the eco ecological shelterbelt system in Yanchi was established and the optimal pattern of forest type,tree species in the sandy area of Yanchi county was put forward.The area of forestland increased from 68.94 thousand ha to 109.05 thousand ha,in which the areas of farmland shelterbelt,economic forest,fuelwood forest and the forest for special use account for 25.68%,20.39%,14.09%,12.09%,10.59%,8.78% and 8.39%respectively.