紫花苜蓿蓄水保土功能与经济效益分析

An Analysis of Soil and Water Conservation Function and Economic Benefit of Medicago sativa

研究了退耕还林地种植的一年生紫花苜蓿蓄水保土功能并进行了经济效益分析。结果表明 :在退耕还林地上种植紫花苜蓿可显著改善土壤的物理性状 ,增加土壤孔隙度 ,减少土壤容重 ,防止水土流失 ,减少土壤侵蚀作用十分显著。其茎叶持水率可达自身重量的 34 3% ,其根系大部分分布在 0～ 30cm土层内。生物量为 5 892t/hm2 ,年产干草 30 0～ 37 5t/hm2 ,直接经济效益达 180 0 0～ 2 2 5 0 0元 /hm2 。

In this paper researches were made on soil and water conservation function and economic benefit of Medicago sativa planted in Sloping Land Conversion Program.The results have shown that planting of Medicago sativa can improve the physical characteristics of soil,increase soil porosity,reduce the volume weight of soil,lessen soil erosion and control water and soil loss.The water retention of its stems and leaves can reach to 34.3% of their own weight;its roots are mainly distributed within a soil layer 0～30 cm thick;its biomass can be as high as 5.89 t/hm^2,and annual dry biomass can reach to 30.0～37.5 t/hm^2.The direct economic benefit can come to (18 000)～22 500 yuan/hm^2.Therefore,both ecologic and economic benefits of Medicago sativa land are of great significance.