南方红壤丘陵区坡改梯后土壤水分概况分析

Analysis on the Soil Moisture Situation after the Terracing in the Red Soil Hilly Areas of South China

本研究采用连续定位观测的方法对江西省进贤县坡改梯后100cm剖面土壤水分进行监测,分析了次降雨、土地利用方式以及土壤物理性质对土壤水分的影响。结果表明:坡改梯后,0～40cm层次土壤成为承载次降雨的主要层次;不同土地利用方式对剖面土壤水分的影响与其对应作物的特性相关,橘树主要吸收利用0～40cm土层水分,因其地表枯枝落叶层较厚、根系深,可改善深层土壤孔隙度从而有利于深层土壤的水分补给。总体而言,坡改梯可有效拦蓄雨水,降低径流系数,坡改梯后种植柑橘等经济林更加有利于发挥梯田拦蓄雨水资源的作用。

In this study,continuous positioning observation was used to monitor soil moisture in a 100 cm profile after the slope was upgraded to terrace in Jinxian County of Jiangxi Province with the analysis on the effects of secondary rainfall,land use patterns and soil physical properties on soil moisture.The results showed that the 0-40 cm soil layer became the main layer for carrying secondary rainfall after the slope was changed into terrace,and the effects of different land use patterns on soil moisture in profile were related to the characteristics of corresponding crops.Orange trees mainly absorbed and utilized the soil moisture at 0-40 cm soil layer because of its thick litter layer and deep root system,which could improve the deep soil pore,so as to be beneficial to the water supply of deep soil.Generally speaking,terraced slope can be used effectively for the interception of rainwater and reduction of runoff coefficient,and planting economic forests such as citrus after terraced slope is more conducive to play the role of terrace for interception of rainwater resources.