水分状况对紫色母岩发育的水稻土团聚体及有机碳分布影响  

INFLUENCE OF SOIL WATER REGIME ON SIZE DISTRIBUTION OF AGGREGATES AND CONCENTRATION OF ORGANIC CARBON THEREIN IN PADDY SOILS DEVELOPED FROM PURPLE SOILS

作　　者：高明[1] 张薇[2] 王子芳[1] 魏朝富[1] 郑杰炳 

机构地区：[1]西南大学资源环境学院,重庆400716 [2]中国科学院西双版纳热带植物园昆明分部,云南昆明650223 [3]重庆地质矿产研究院,重庆400042

出　　处：《土壤学报》2008年第5期943-949,共7页Acta Pedologica Sinica

基　　金：国家科技支撑计划项目(2006BAD05B01-02和2008BABA7B09-03);重庆市自然科学基金项目(9066)资助

摘　　要：在紫色丘陵区采集了因水分状况影响而形成的4种类型紫色水稻土土样，利用湿筛法获得不同粒径的团聚体，分析了其有机碳和不同土壤发生层中易氧化碳、微生物生物量碳和水溶性碳含量。结果表明，A层土壤中〉2mm的团聚体以潜育型水稻土和渗育型水稻土最高，分别占76．65％和75．92％，其次是潴育型水稻土占43．86％，淹育型水稻土只有13．10％；不同土壤发生层间土壤团聚体的组成也存在较大的差异；除潴育型水稻土的P层外，其余各层土壤的有机碳53．7％-96．2％均分布在〉0．25mm团聚体中；潜育型水稻土的微生物生物量碳和易氧化碳含量在4种水稻土中最高，分别为282.5mg·kg^-1和6.59g·kg^-1，水溶性有机碳则以渗育型水稻土最高；有机碳含量与〉2mm团聚体含量呈极显著正相关关系，与〈0．25mm微团聚体数量呈显著负相关关系。Aggregation and soil organic carbon （SOC） concentration represent integrated effects of soil type,environ- ment,plant species, and soil management practices. This study was conducted to assess effect of water regime on size distribution of soil aggregates and C concentrations therein in paddy soils developed under different water conditions from purple soils in a purple hilly area of the Sichuan basin. The labile organic carbon,microorganism biomass carbon,water dissolved carbon ,and organic carbon concentration in aggregates of different sizes gained by the wetting sieve method were determined. The content of aggregates 〉 2 mm in diameter was the highest in the cultivated horizon of gleyed paddy soils and percogenic paddy soils, being 76.65% and 75.92% , respectively, and only 13.10% in the cultivated horizon of submergeric paddy soil. There was no significant difference in size distribution of soil aggregates between soil genetic horizons, either. Except in the P horizon of hydromorphic paddy soil,major portion （53.7%-96.2% ） of soil organic carbon was distributed in the aggregates 〉 0.25 mm in diameter in the soils. The concentration of microorganism biomass carbon and labile carbon in hydromorphic paddy soils was the highest among the soils,being 282.5mg·kg^-1 and 6.59g·kg^-1,respectively. The concentration of water dissolved carbon was the highest in percogenic paddy soils. A significantly positive corre- lation was also observed between the content of aggregates 〉 2 mm in diameter and the concentration of organic carbon, and a significant negative one between the content of aggregates 〈 0.25 mm in diameter and the concentration of organic carbon.

关 键 词：水分状况 紫色水稻土 团聚体 有机碳 

分 类 号：S152.4[农业科学—土壤学]