岩溶山地石漠化地区不同土地利用方式下的土壤物理性状分析

分析研究了重庆市北暗区岩溶槽谷鸡公山地区不同土地利用方式下的土壤主要物理性质,认为随着岩溶地区土地由自然林地向草坡地、人工林地、菜地、耕地转换,土壤砂化严重,土壤容重增加,总孔隙度,尤其是非毛管孔隙度明显降低,用干筛测得的各不同土地利用方式下土壤团聚体结构相差不大,而用湿筛测得的土壤水稳性团聚体相差较大,团聚体结构破坏率较大。随着岩溶地区土地由菜地、耕地向撂荒地转换,土壤各项物理指标都有改善。在此基础上认为,土壤物理性质的变坏与石漠化形成过程有相互促进的正反馈关系,在退化方向和阶段上具有一致性和同步性,但土地撂荒后可以较大程度的减少水土流失。

Analysis on Physical Feature of Karst Mountains Desertification Soil Under Different Land Use

The physical property of karst mountain desertification soil under different land use in Chongqing Beipei karst mountain was studied. The result shows that when the nature forest land is replaced by grass land,artificial land, vegetable land and plantation gradually, the land is becoming more arenaceous and the soil bulk density in- creases, and the total percentage of pore, especial the percentage of non-pore increase greatly. Although the ag- gregate structure measured by dry sieve are quiet similar under different land use, the water-stable aggregate structure got by dump sieve is quite different. The destroy of aggregate structure is high. With the vegetable land and plantation changed into deserted land, all physical standards are improved. On the basis of those studies, the author briefly analyzed the correlation between the degrading soil physical feature and the desertification, and pos- sibility of reducing the soil erosion by deserting land.