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干旱、半干旱地区土壤表层生物结皮的发育,改变了表层土壤的粗糙度和理化性质,其较高的持水性和对降水入渗的阻碍作用,改变了降水在土壤中的再分配过程,这不但影响土壤种子库中种子的组成和种子萌发,而且影响着上层植被的演替;生物结皮的形成和发育,使降水再分配过程浅层化,提高了浅层土壤水分的含量;而生物结皮对降水入渗的阻碍作用使深层土壤水分状况日益恶化,久之将导致区域内深根系植物的衰退,浅根系半灌木和草本植物得到发展,从而引起植被的演替。
The development of soil surface crusts in arid and semi-arid regions changed the roughness and physico-chemical properties of surface soils, and their high water holding capacity and the impediment to precipitation infiltration had changed the redistribution of precipitation in soil. This not only affected seed composition and seed germination in the soil seed bank, but also affected the succession of the upper vegetation. The formation and development of biological crusts made the precipitation redistribution process shallow and increased the soil moisture content in shallow soil. The deteriorating effect of biological crusts on rainfall infiltration has deteriorated the soil moisture status of the deep soil layer. For a long time, the decline of deep-rooted plants in the area will lead to the development of shallow-rooted semi-shrubs and herbaceous plants, which will lead to the succession of vegetation.