黄土高原生态脆弱地带植被恢复水资源承载能力  

Water Resources Carrying Capacity for Vegetation Restoration of Eco-fragile Region in the Loess Plateau

作　　者：刘广全[1,2,3] 匡尚富[1,2] 土小宁[4] 焦醒[2] 周海光[2] 

机构地区：[1]国际泥沙研究培训中心,北京100048 [2]中国水利水电科学研究院,北京100048 [3]西北农林科技大学,杨凌712100 [4]水利部水土保持植物开发管理中心,北京100038

出　　处：《国际沙棘研究与开发》2010年第1期13-20,共8页

基　　金："十一五"国家科技支撑计划(2006BAD09B06;2006BAD03A0308);水利部"948"项目(200207)联合资助

摘　　要：本文以黄土高原生态脆弱地带典型人工成林为研究对象,定位观测了林地树木蒸腾、土壤蒸发及土壤水分状况等,分析评价了土壤水分特征,提出了植被恢复初植密度及其动态调控方案。结果表明:测定的林分在植被生长季节内,丰水年土壤贮水量总体为盈余,100cm以上土层水分补充明显,100cm以下土层水分一般呈负增长;平水年的同期降水不能满足林地蒸散消耗;枯水年土壤水分明显亏缺。以多年平均降水量为标准,河北杨、小叶杨、山杏、山桃、柠条和沙棘6种林分稳定密度应分别为:196、332、332、872、757、1438株(丛)/hm2,初植密度(以株数保存率65%核算)应分别为:302、511、511、1342、1165、2212株(丛)/hm2。研究区植被恢复造林密度过大是造成土壤水分亏缺、植被生态效益和经济效益难以发挥的重要因素。根据水资源承载力合理确定林分密度能够实现植被生态功能持续发挥、群落稳定演替进而改善生态环境、促进可持续发展的作用。This paper studied the water resources carrying capacity for plantation of ecological fragile region in the Loess Plateau. The study observed the transpiration, soil evaporation and soil moisture in forest and analyzed the soil water characteristics. The initial planting density and dynamic control plan was suggested. The results showed that during the plant growing period the soil water had sur- plus in the wet year. The soil moisture above 100cm soil layer was significantly replenished while the soil moisture below 100cm soil layer grew negatively. In the normal year the precipitation could not meet the consumption of forest evapotranspiration. And the soil moisture was deficient in the dry year. Considering average annual rainfall, the steady densities of 6 tree pieces, Populus hopeiensis, P. sirnonii, Armeniaca ansu , Persica davidiana , Caragana spp. and Hippophae rharnnoides , could be 196, 332, 332, 872, 757, 1438 trees/hm^2. The initial planting densities of 6 tree pieces could be 302, 511, 511, 1342, 1165, 2212 trees/hm^2. The too heavy density of plantation in the region would cause the soil moisture deficit and the difficult for forest to play a role in ecosystem and economics. A reasonable stand density according to the water resources carrying capacity could achieve the ecological functions of vegetation and community＇ s steady succession which would be better for environment.

关 键 词：黄土高原 生态脆弱地带 水量平衡 植被密度 

分 类 号：X143[环境科学与工程—环境科学]