土壤水分植被承载力研究成果在实践中的应用

论文以黄土高原半干旱区柠条林为例，探讨了土壤水分植被承载力研究成果在生产中的应用。结果表明，土壤水分植被承载力不仅是确定森林植被恢复目标、调控植物水关系的理论基础，而且是确定森林植被合理经营方向和利用强度的理论基础。如果人工林密度大于土壤水分承载力，需要对人工林进行疏伐；如果人工林密度小于土壤水分承载力，需要增加密度或改换植被类型。当人工林密度等于土壤水分承载力时，人工林可持续利用土壤水资源。土壤水分承载力时的柠条林可以作为薪炭林和放牧林经营。单位面积结实量与密度关系可用正态分布曲线描述。承载力时的柠条林不仅能有效地保持水土，而且能生产较多的种子，又是良好的蜜源植物，宜作为水土保持林经营。该研究结果可为人工植被恢复和可持续经营提供科技支撑。

Use of the Theory of Soil Water Carrying Capacity for Vegetation in Practice

Taking the Caragana in the semiarid area of loess hilly region as an example, the use of SWCCV in practice was researched in the paper. The results show that SWCCV, short for soil water carrying capacity for vegetation, is the foundation of determining not only the goal of forest and vegetation rehabilitation and the regulation of the relationship between plant growth and soil water at the whole plant level in a plant community, but also management direction and using intensity of the forest and vegetation. If the density of trees is bigger than the value of SWCCV, the relation between water and plant needs to be regulated. If the density of trees is smaller than the value of SWCCV, we should change the type of forest and vegetation or increase the density of trees. When the density of trees is equal to the value of SWCCV, it benefits sustainable management of forest. Caragana shrub forest can be managed as fuel forest and grazing forest when the density of trees is equal to SWCCV. The relation between seed yield per unit area and density can be expressed by normal distribution model. Caragana shrub yields smaller seed when density of trees is equal to SWCCV. Managed as the soil and water conservation forest, Caragana forest not only conserves soil and water effectively and get better economic benefits, but also is a source of nectar. The results provide the basis for vegetation rehabilitation and the sustainable management of the artificial forest.