Research On Ecological Efficiency Evaluation Of Sand-fixed Forst In LongQingxia Alluvial Flat, BeiJing

Based on the theory of recovery ecology, The paper systematically describes the change of ecological benefit main element in wild artificial vegetation recovery area LongQingxia alluvial flat,BeiJing using the ecological system positioning. Taking example for different forest species of all soil dessing artificial vegetation recovery areas in LongQingXia barren waste, It also studies the soil benefit, the benefit of wind prevention and erosion resisting, biology benefit and microclimate benefit of barren waste artificial vegetation recovery area introducing applied mathematics methods to do quantization analysis and synthetical ecology benefit evaluation. The achievement of this study provides important theoretical and practical value to the benefit evaluation of artificial vegetation recovery area. The main achievement of the paper is :(1)The econological effects in LongQingXia barren waste artificial vegetation recovery area is obviously: the rate of the silt and cosmid is increased, volume density of soil and the content of moisture is increased, the air amount is increased, the vegetation has obvious effects on the soil nutrient, with the growth of vegetation, covering barren field surface, the roughness of artificial vegetation recovery area field surface is increased, the wind speed of near field surface is slowed down obviously, and the nature dustfall is declined; species and quantity of herbaceous plants in the forest are increased; Artificial recovery vegetation community has the ecological efficiency of decreasing the temperature , increasing the moisture and conserving water source .(2)Based on the thoroughly analysis of biological benefit, soil nutrient benefit, microclimate benefit and hudrology benefit in the whole soil dessing artificial vegetation recovery areas in LongQingXia barren waste, the paper does quantization analysis and synthetical ecology benefit evaluation by applied mathematics methods. The synthetical ecological benefit exponent of Xinjiang poplar forest, mixed forest and bastard acacia forest is far more than nature uneven ground in the whole soil dessing artificial vegetation recovery areas of LongQingXia barren waste. The order of synthetical ecological benefit is: mixed forest> Xinjiang poplar forest> bastard acacia forest> nature uneven ground.