摘要
学研究院亚热带林业研究所,浙江富阳311400)摘要大量岩石出露于地表是中国西南喀斯特地区石漠化典型的表观特征之一。为了揭示裸露岩石周围土壤水分对裸岩的响应,于西南地区发生特大干旱期间(2009年9月—2010年2月),研究了裸岩周围土壤水分的动态变化。结果表明:干旱期间,岩石北方土壤表层含水量高于东方、西方、南方(P<0.01),且表层土壤含水量随岩石高度增加而增加;岩石出露面积与其西方、北方土壤含水量极显著相关(P<0.01),与东方土壤含水量显著相关(P<0.05);岩石的尖削程度越大,东、西、北方土壤含水量越低;岩石周围北、东、西方土壤含水量表现出随距离增加先升高后降低趋势,而岩石南方表现为随距离增加而增加的趋势;岩石周围土壤含水量均随土壤深度增加而增加。裸岩在干旱期间表现出遮荫作用,导致岩石北方土壤含水量高于其他方向,并在距离岩石15cm处形成逆境背景下相对有利的人工恢复植被位点,对指导石漠化生态治理过程中植被恢复工作具有重要意义。
The Karst rock desertification （KRD） in Southwest China is characterized by a large number of rocks cropping out from the ground. To understand the responses of soil moisture to the bare rocks, a monitoring was made on the dynamic changes of soil moisture in a KRD region during an extreme drought period from September 2009 to February 2010. During this drought period, the soil moisture content on the north side of the rocks was significantly higher than that on the east, west, and south sides （P〈0.01）, and the surface soil moisture content increased with the protruding height of the rocks. There existed significant correlations between the sizes of the bare rocks and the soil moisture content on the west and north sides （P〈0.01） and on the east side （P〈0.05） of the rocks. Sharper rocks were associated with lower soil moisture content on the east, west, and north sides of the rocks. With the increasing distance from the rocks, the soil moisture content decreased after an initial increase on the north, east, and west sides, but showed an increasing trend on the south side. The soil moisture content around the rocks in- creased with soil depth. During the drought period, bare rocks presented shading effect, resulting in higher soil moisture content on the north side of the rocks, as compared to the other three sides. The location at 15 cm north of the rocks had the highest soil moisture content, being a favorable site for the vegetation restoration under stressful environmental conditions in the KRD area. These research findings would have significance in the vegetation restoration of the ecosys- tems damaged by the KRD process.
出处
《生态学杂志》
CAS
CSCD
北大核心
2012年第12期3174-3178,共5页
Chinese Journal of Ecology
基金
国家林业局林业公益性行业科研专项(201004033)
国家自然科学基金项目(30972351)
中国林业科学研究院亚热带研究所基本科研业务费专项(RISF61251)资助
关键词
石漠化
裸岩
土壤水分
遮荫
干旱
Karst rock desertification （KRD）
bare rock
soil moisture
shading
drought.
