摘要
在长期定位试验基础上研究传统耕作(T)、免耕不覆盖(NT)和免耕秸秆覆盖(NTS)3种耕作措施对土壤团聚体分布及其稳定性的影响。结果表明,3种耕作措施连续实施5年后,使耕层土壤容重显著增加,免耕秸秆覆盖显著增加了表层土壤有机质。NTS处理>0.25mm团聚体含量(R0.25)显著高于T处理和NT处理的,同时也明显高于2004年的背景值,0-30cm土层范围内平均较T处理和NT处理分别高14.88%和6.40%;免耕和免耕秸秆覆盖可显著改善土壤耕层(0-20cm)团聚体的水稳定性。NTS处理0-30cm的不稳定团粒指数(ELT)与2004年背景值比较,平均下降了1.88%。说明相对于传统耕作,免耕秸秆覆盖减少了机械的破坏作用,增加了土壤有机质含量,促进耕层团聚体形成,并提高了其稳定性。
Based on a long-term field experiment, the effects of conventional tillage（T）, no-tillage without wheat stubble mulching （NT） and no-tillage with wheat stubble mulching （NTS） on soil aggregates size dis- tribution and stability of winter-wheat field were studied. The results showed that NTS significantly in- creased the soil bulk density of plough layer and the organic matter of top layer. Compared with the back- ground values in 2004, macro-aggregates significantly increased in NTS, was 14.88% and 6.40%higher than that of T and NT. NT and NTS significantly improved the aggregates water stability of 0-20 cm layer. The unstable aggregate index （ELT） of 0-30 cm layer averagely decreased by 1.88 % in NTS compared with the background value in 2004. Consequently, no-tillage with wheat stubble mulching increased the plough layer aggregation and its stability of soil aggregates due to less mechanical disturbance and increased organic matter.
出处
《水土保持学报》
CSCD
北大核心
2011年第6期119-123,共5页
Journal of Soil and Water Conservation
基金
农业部公益性行业(农业)科研专项(201103001)
甘肃省科技厅工程技术中心建设计划(093NTGA007)
甘肃农业大学创新基金(GAU-CX1029)
关键词
免耕
秸秆覆盖
土壤团聚体
no-tillage
stubble mulching
soil aggregates
