元谋干热河谷8种植被类型的林地土壤特性研究

通过对元谋干热河谷区加勒比松人工林、加勒比松 车桑子人工混交林、山合欢天然更新林、车桑子 山毛豆人工混交林、桉树人工林、草地、荒坡、膨胀土8种植被类型林地1 m土层内不同层次雨季(8月2日~9月2日)土壤水分含量的分析研究得出:在雨季8种植被类型林地土壤的水分含量均较低,因其土壤的物理性能较差,故蓄水保水能力也较差;各植被类型林地土壤的有机质、养分含量均极低,按照土壤养分含量分级标准,各植被类型林地土壤的养分含量均在6级以下。元谋干热河谷区林地土壤的贫瘠特性致使林木长势较弱,是造成其植被恢复困难的一个原因。

A Study on Soil Characteristics of Eight Vegetation Types in Yuanmou Dry and Hot Valley

The water contents in 1m soil layer of eight vegetation types in Yuanmou dry and hot valley in rainy season(August 2 to September 2) were measured and analyzed.These eight vegetation types are Pinus caribaea plantation,Pinus caribaea Dodonaea viscosa plantation,Albizzia kalkora natural regeneration forest;Dodonaea viscosa Tephrosia candida plantation,eucalyptus plantation,grassland,waste land and expansive soil.The study results showed that in the rainy season the water contents of these eight kinds of sites in Yuanmou hot and dry valley were all considerably low.It is mainly because the poor physical properties,the moisture-holding capacity of the soil was also low.The contents of organic matter and nutrients were all low,according to the grading standard of soil nutrient contents,the soil nutrient contents of all the study sites were below grade 6.The soil of Yuanmou dry and hot valley is very poor,which is a major reason for the weak growth of the forest trees and the difficulties in revegetation.