桂西北喀斯特典型土壤的大团聚体分级特征研究  

Characteristic of Soil Aggregate Structure in Different Typical Soils in Karst Region of Northwest Guangxi,China

作　　者：胡乐宁[1,2,3] 苏以荣[1,2] 何寻阳[1,2] 

机构地区：[1]中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,湖南长沙410125 [2]中国科学院环江喀斯特农业生态试验站,广西环江547100 [3]广西师范大学环境与资源学院,广西桂林541004

出　　处：《广西师范大学学报（自然科学版）》2013年第3期213-219,共7页Journal of Guangxi Normal University:Natural Science Edition

基　　金：中国科学院战略性先导科技专项(XDA05070403);中国科学院西部行动计划项目(KZCX2-XB3-10);国家科技支撑计划项目(2012BAD05B03-6);广西自然科学基金资助项目(2013GXNSFBA019080);广西师范大学博士启动资金资助项目

摘　　要：为了研究喀斯特地区的典型土壤大团聚体分级特征,采用A S200机械干筛和湿筛的方法,分析不同有机碳含量的3种喀斯特典型土壤(红壤、棕色石灰土、黑色石灰土)的大团聚体颗粒分级情况。通过对大团聚体破坏率(PAD)、平均质量直径(MWD)和水稳性团聚体(WSA)的分析,结果显示,平均质量直径和水稳性团聚体从大到小为:黑色石灰土>棕色石灰土>红壤(p<0.05)。在相似有机碳含量条件下,不同类型土壤的P AD值显示红壤最易被湿筛过程破坏,其次是棕色石灰土,最后是黑色石灰土,说明石灰土大团聚体机械稳定性强于红壤,且石灰土抵抗因降雨引起的土壤侵蚀的能力强于红壤。可见,不同桂西北喀斯特地区典型土壤大团聚体颗粒分级差异较大,且与土壤有机碳含量密切相关。从大团聚体聚合角度来看,喀斯特石灰土有利于SOC的固定,土壤稳定性较强。In order to know the soil aggregate characteristic on typical Karst soils,two Karst soils （terra fusca and rendzina） and a zonality soil （red soil） were selected with different soil organic carbon （SOC）content for study.Soil aggregates were obtained with dry sieving method and wet sieving method for soil stability （PAD,MWD,WSA） analyses.The results showed that,MWD and WSA were in order of rendzina〉terra fusca〉red soil（p〈0.05）.On the condition of the same content of SOC,red soil was the most easily to be destroyed than terra fusca and rendzina according to the result of PAD,This implied that Karst soil aggregate mechanical stability was better than that in red soil,and the resistance of soil erosion caused by rainfall resistance in Karst soils was better than that in red soil.There are significant differences between Karst soils and red soil,and it is closely related to SOC.From the point of view of soil aggregate,it benefits the stability of Karst soil SOC.

关 键 词：喀斯特 大团聚体破坏率 机械分级 水稳性团聚体 

分 类 号：S153.6[农业科学—土壤学]