摘要
基于在黄土高原半干旱地区的典型代表—定西市安定区连续进行6 a的保护性耕作试验,研究了不同耕作方式对土壤总有机碳和活性有机碳的影响,并对各处理的碳库活度(A)、碳库活度指数(AI)、碳库指数(CPI)和土壤碳库管理指数(CMPI)进行了计算。结果表明:与传统耕作不覆盖(T)相比,免耕秸秆覆盖(NTS)、传统耕作结合秸秆还田(TS)和免耕不覆盖(NT)有利于土壤总有机碳含量和活性有机碳含量的提高,并且有随着土层深度的增加而递减的趋势;NT、NTS和TS有助于提高0～5 cm土层土壤活性有机碳占土壤总有机碳的百分率,尤以NTS处理的效果最为明显,说明NTS处理的土壤碳素活性大、易转化;对碳库各项管理指数来说,总体上秸秆覆盖或还田的贡献大于耕作措施,说明对土壤进行秸秆覆盖或还田有利于土壤碳库管理指数提高。
Based on the experiment of 6-year conservation tillage in Dingxi specific semiarid areas in the Loess Plateau. The total organic carbon（TOC） and active soil organic carbon （ASOC） of different tillage methods were studied, and the activity of carbon pool （A）, activity index（AI）, carbon pool index（CPI）, carbon pool management index（CPMI） of different treatments were calculated. The results showed that the contents of TOC and ASOC in no-till with straw mulching（NTS）, conventional tillage with straw incorporated（TS）, non~ till without straw mulching（NT） were more than conventional tillage with no straw（T）, and the contents of TOC and ASOC decreased with the soil depth. The percentage of ASOC in TOC was higher in NT, NTS and TS than T in 0-5 em soil layer, especially in NTS. The result demonstrated that the activity of the carbon in soil of NTS was higher and could convert easily. Stubble return effect was more than tillage form for different soil C pool management index, so stubble return was advantages to improving the soil C pool management index.
出处
《干旱地区农业研究》
CSCD
北大核心
2008年第6期8-12,共5页
Agricultural Research in the Arid Areas
基金
ACIAR资助(LWR2/1999/094)
国家科技支撑计划(2006BAD15B06)
关键词
耕作方式
总有机碳
活性有机碳
碳库管理指数
tillage method
total organic carbon
active soil organic carbon
carbon pool management index
