Soil Moisture Characteristics in Karst Area with Different Land Use Types  

岩溶区不同土地利用方式下的土壤水分特征研究(英文)

作　　者：谢世友[1,2] 任伟[1] 

机构地区：[1]西南大学地理科学学院,重庆400715 [2]西南大学三峡库区生态环境教育部重点实验室,重庆400715

出　　处：《Agricultural Science & Technology》2013年第12期1856-1860,1864,共6页农业科学与技术（英文版）

基　　金：Supported by National Key Program of Science and Technology(2011BAC09B01,2006BAC01A16);Natural Science Foundation Project of Chongqing(CSTC,2009BA0002)~~

摘　　要：Ecological efficiency changes of soil moisture were researched in karst areas with different land type uses, including farmland, abandoned farmland （1 y） and shrub land （1 y）, sparse wood land （15 y）, secondary forest （25 y） and the re- sults showed that physical property of soil was not a simple ＂improvement＂ process during land type evolution. Specifically, from farmland to secondary forest, the con- tent of topsoils changed from being washed away to accumulation and soil bulk density changed from increasing to decreasing. For example, soil bulk densities of abandoned farmland and shrub land increased by 6.6% and 11.57% compared with farmland, and of sparse wood land and forest land decreased by 5.0% and 10.0%. The change trend of soil bulk density was just in contrary to total porosity. Available water capacity was the lowest of shrub land, but increased in rest land types. The increase tended to be volatile in 5.1%-12.5% of different land types and water-sta- ble aggregate content （〉0.25 mm） reached the highest of sparse wood land. The destruction rate, however, was declining in the process of land type evolution and the increase was in the range of 34.0%-64.7% compared with farmland. The de- struction rate of aggregate was of negative correlation with organic matter. Water- holding capacity was the best of forest land and abandoned farmland and the poor- est of shrub land, close to sparse wood land. Water-supplying capacity from high to low was as follows： farmland〉sparse wood land〉secondary forest〉shrub land〉a- bandoned farmland. It is obvious that water-holding capacity and water-supplying capacity are not consistent, but both are closely related to the content of soil clays, porosity, and aggregate stability.研究了喀斯特山区耕地、1年弃耕地、灌草地、15年疏林地、25年次生林（侧柏）地植被演替过程中土壤水分生态效应的变化,结果表明土壤物理性质并不是简单的＂改善＂过程：表层粘粒含量由流失逐渐转为积累;容重先升高后降低,弃耕地和灌草地较耕地增加了6.6%和11.57%,疏林地和林地较耕地减少了5.0%和10.0%;总孔隙度变化趋势与容重刚好相反;土壤有效水含量以灌草地最低;各恢复阶段表层〉0.25mm水稳性团聚体含量较耕地的增幅为5.1%~12.5%,疏林地最高;团聚体破坏率随演替的进行依次降低,较耕地降幅为34.0%~64.7%,且与有机质呈显著负相关;土壤持水能力以林地和弃耕地最好,灌草地最差,耕地接近于疏林地,土壤供水能力强弱依次为耕地〉疏林地〉林地〉灌草地〉弃耕地,土壤持水和供水能力并不一致,但都与粘粒含量、孔隙状况和团聚体稳定性等土壤结构指标密切相关。

关 键 词：Karst area Land use type Soil moisture characteristics 

分 类 号：S152.7[农业科学—土壤学]