云南元谋干热河谷区旱坡地不同生态农业模式土壤水分差异性分析

Variability in soil moisture under four eco-agricultural models on dry slope land in Yuanmou dry-hot valley

对干热河谷旱坡地Ⅰ（罗望子＋木豆）,Ⅱ（罗望子＋木豆＋柱花草）,Ⅲ（罗望子＋象草）,Ⅳ（罗望子＋自然草被）等4种复合生态农业模式0-40 cm土层水分进行监测和分析的结果表明：4种模式的土壤含水量主要受自然降水的影响,雨季和旱季差异显著;不同模式对土壤含水量的影响存在差异,其中,模式Ⅱ和模式Ⅳ有较强的保水持水能力;在雨水补给不足时,模式Ⅲ对土壤水分的利用效率最高,模式Ⅳ最低;土壤水分季节波动模式Ⅳ最小,模式Ⅲ波动最剧烈;雨季,4种模式具良好的层间补水能力,旱季,模式Ⅰ和Ⅱ土层间补水能力最强。总体上看,4种模式对干热河谷旱坡地的土壤水分均有一定的保持能力,但模式Ⅱ的保水持水能力最强,综合效益最好,更利于干热河谷旱坡地生态农业的可持续发展。

The analysis was made of soil moisture in the 0～40 cm soil profile under four eco-agricultural models on dry slope land in a dry-hot valley.The results showed that soil moisture content was influenced mostly by precipitation,and it had conspicuous difference between rainy and dry seasons.Soil moisture content varied under different modles.Model Ⅱ and Ⅳ had strong water-holding power,while model Ⅲ had the topmost water use efficiency when the precipitation was lack,but model Ⅳ＇s was the lowest.The seasonal fluctuate on soil moisture of the model Ⅳ was the lowest,but model Ⅲ＇s was the highest.In rainy season,four models had good water supply ability between soil layers.In dry season,model Ⅱ and Ⅰ had only good water supply ability between soil layers.As the whole,four models had part water-holding power,but model Ⅱ was the best one on synthetical benefit,it will make development on eco-agriculture in the dry-hot valley.