近40年泥河沟流域耕地土壤有机质含量的变异性  

Temporal Variability of Soil Organic Matter Content in Cultivated Lands in Nihegou Watershed

作　　者：吴驳 吴发启[2] 佟小刚[2] 宋敏敏[2] 侯雷 WU Bo;WU Faqi;TONG Xiaogang;SONG Minmin;HOU Lei(Institute of Soil and Water Conservation,Northwest A&F University,Yangling,Shaanxi 712100,China;College of Resources and Environment Sciences,Northwest A&F University,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学水土保持研究所,陕西杨凌712100 [2]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《土壤》2020年第1期174-179,共6页Soils

基　　金：国家重点基础研究发展计划(973计划)项目(2007CB407201-5);国家自然科学基金项目(41271288)资助。

摘　　要：利用方差和变异系数分析了近40 a黄土高原泥河沟流域土壤有机质含量的时间变异性,分离了相关因素对总变异的影响。结果表明,1980年以来耕地土壤有机质含量呈阶段性上升趋势,变异性先增高后降低;修筑梯田、沟边防护和增施化肥对土壤有机质含量的变异起了很大的作用,增施化肥的影响效果略大于修筑梯田的效果;修筑梯田在初期因土壤扰动的影响,会造成土壤有机质含量的下降,而沟坡防护虽然只能在较小的面积上起到作用,但避免了土壤扰动,起到的效果更好;各类因素引起的变异是一种长期积累的过程,这个过程中土壤有机质含量并不会无限度地上升,含量越高上升越不明显。该区耕地土壤有机质含量从1980年的9.52 g/kg到2015年的14.58 g/kg,已由第二次全国土壤普查含量分级中的第7级上升到第5级,体现了该区的治理效益,也为今后流域的治理和管理提供了依据。Variance and coefficient of variation were used to analyze temporal variability of soil organic matter(SOM)content in the Nihegou watershed in the loess plateau from 1980 to 2015,and isolated the effects of factors on total variation.The results showed that SOM content of cultivated land showed an increasing trend since 1980,the variability increased first and then decreased.Building terraces,slope protection and increasing fertilizer application had great effects on the variation of SOM content,and the effect of increasing fertilizer application was slightly more than that of building terraces.Building terraces caused the loss of SOM in the initial stage due to soil disturbance.Although slope protection only played a role in the smaller area,it avoided soil disturbance thus had a better effect.The variation caused by all factors was a process of long-term accumulation,in which SOM did not increase endlessly.The higher the content of SOM,the less obvious the increase.SOM content of farmland increased from 9.52 g/kg in 1980 to 14.58 g/kg in 2015,which was improved from the 7th level to the 5th level in the 2nd national soil survey classification.The above results reflect the governance benefit of the watershed,and provide a basis for watershed management and management in the future.

关 键 词：泥河沟 耕地 土壤有机质 时间变异性 

分 类 号：S158[农业科学—土壤学]