贵州省喀斯特峡谷花椒林地土壤水分特征研究

以贵州省花江喀斯特峡谷花椒林地土壤水分全年的动态变化特征为研究对象，分析了土壤含水量与土壤结构、植被间的关系以及不同土壤层次水分动态变化规律，划分出了土壤水分垂直变动带。研究结果表明，表土层土壤蓄水能力大于底土层，土壤实际含水量表现为林地高于休闲地，土壤深层高于表层。表层水分变化最快，影响因素为大气降水与棵间蒸发。中间层次之，主要受蒸腾作用及水分垂直运动特征影响，底层最慢，其持水量受土壤结构的影响。土壤水分垂直变动带划分结果为：0-20cm为强烈变动带，20-50cm为过渡带，50cm以下为稳定带。

Characteristics of Soil Moisture on Zanthox ylum Forest Land in Karst Valley of Guizhou Province

This study takes the dynamic characteristics of soil moist ure of a whole year on Zanthoxylum Forest land in Huajiang karst valley, Guizhou Province as the overall objective.The relationships between soil water content and soil structure, vegetation hararteristics, and the dynamics of soil moist ure in different soil layers are analyzed and the change zones of soil water content in vertical direction are divided.Results indi- cate that water holding capacity of topsoil is higher than that of subsoil.The actual water content on forest land is higher than fallow land, and in deeper soil, higher than surface soil.Soil water content wit hin topsoil changes fastest due to the effects of evaporation and precipitation and it follows by intermediate layer and deepest layer due to the effects of transpiration and soil struct ure, respectively.Vertical change zone of soil moisture can be divided as follow: 0-20 cm is the rapidly changing layer, 20-50 cm is the transitional layer, and >50 cm is the stable layer.