花江峡谷不同植被类型下土壤水分时空分布特征

花江峡谷是一个严重石漠化的喀斯特峡谷,水分是花江峡谷植物生长发育的主要限制因子,故在花江峡谷区如何选择适当的植被类型是充分利用降水和防止水土流失的一个重要环节。通过研究花江峡谷区不同植被类型下土壤水分的时空分布特征,探讨适合该区生态修复的植被类型,为峡谷区生态建设与水土保持提供依据。研究结果表明:(1)在空间分布上,多年生的柚木对土壤深层水分的影响较大;花椒树(特别是长势好的花椒树木)对土壤水分的保持具有明显作用。(2)在时间分布上,各种植被类型下的土壤含水量均随降雨量的多少而升降,但进入12月份在降雨量最低的情况下,花椒的土壤含水量甚至出现升高的现象,反映了花椒特有的保持水土、涵养水源的作用。研究结果证明大面积种植花椒树有利于提高研究区的生态、经济效益。

Characters of Spatial and Temporal Distribution of Soil Moisture under Different Vegetation in Huajiang Valley

Huajiang Valley is a karst gorge of serious stony-desertification.The moisture is the main restriction factor of plant growth in Huajiang Valley.So to choose the appropriate vegetation type to fully utilize precipitation and prevent soil erosion is an important element in the Huangjiang Valley district.The spatial and temporal distribution character of soil moisture under the different vegetation in Huajiang Valley is studied in this article.And the right plant type which can be more beneficial to ecological balance and conserve water and soil is also discussed.The results show that not only on the spatial distribution,but also on the temporal distribution,the Chinese prickly ash has the best efficacy to converse water and soil.In a word,the Chinese prickly ash can improve the ecological and economic benefits of Huajiang Valley.