轮耕对冬春休闲旱地土壤结构及团聚体稳定性的影响  

Effects of rotation tillage patterns on soil aggregates stability and soil structure of the dry land in winter and spring fallow period

作　　者：赵冀 王维 张鹏[1] 侯贤清[1] 贾志宽[1] 韩清芳[1] 

机构地区：[1]农业部西北黄土高原作物生理生态与耕作重点实验室/西北农林科技大学农学院,陕西杨凌712100 [2]宣化科技职业学院,河北张家口075100

出　　处：《干旱地区农业研究》2017年第6期52-58,115,共8页Agricultural Research in the Arid Areas

基　　金：国家"十二五"863课题(2013AA102902);"十二五"国家科技支撑计划课题(2012BAD09B03);高等学校学科创新引智计划项目(B12007);公益性行业(农业)项目(201303104)

摘　　要：为了探索半干旱区合理的耕作制度,改善旱地土壤结构,提高农田生产力,于2007—2010年在宁南旱区进行了冬闲期免耕/深松/深松(N/S/S)、深松/免耕/免耕(S/N/N)、连年免耕(NT)及连年翻耕(CT)4种不同耕作模式试验,研究了轮耕对土壤孔隙度、团聚体结构组成及其稳定性的影响。结果表明,N/S/S轮耕处理较CT和NT显著降低了冬春休闲旱作农田0~20 cm土层的土壤容重和土壤孔隙度,降低幅度2.5%~3.1%,较S/N/N轮耕处理20~40 cm土层土壤孔隙度提高了2.8%(P<0.05);NT处理与S/N/N轮耕处理0~40 cm土层>0.25 mm机械稳定性与水稳性团聚体含量、平均重量直径(MWD)和几何平均直径(GMD)均高于翻耕处理。连续两年以上免耕处理(NT和S/N/N)能够促进旱作农田土壤团聚体的形成,增加了土壤团聚体平均重量直径和几何平均直径,降低了土壤团聚体的破坏率,提高了土壤的结构稳定性。To further explore the reasonable farming system in semiarid area,the effects of rotation tillage patterns on soil aggregates stability and soil structure of the dry land in winter and spring fallow period were conducted in south Ningxia from 2007 to 2010. There were four tillage treatments: no-tillage→subsoiling tillage→subsoiling tillage( N/S/S),subsoiling tillage→subsoiling tillage→no-tillage( S/N/N),no-tillage→no-tillage→no-tillage( NT) and conventional tillage( CT) as control. The effects of different tillage patterns on soil porosity,composition and stability of soil aggregate were examined. The results showed that in 0 ~ 20 cm soil layer,the soil bulk density and the soil porosity of N/S/S was significantly( P<0.05) decreased by 2.5% ~ 3.1% compared with CT and NT.The soil porosity in 20 ~ 40 cm soil layer of N/S/S was significantly increased by 2.8% compared with S/N/N( P<0.05). NT and S/N/N treatments were higher content of mechanically stable aggregates,water-stable aggregates,mean weight diameter( MWD) and geometric mean diameter( GMD) than CT in 0 ~ 40 cm soil layer. No-tillage more than two consecutive years( NT and S/N/N) could increase the mean weight diameter( MWD) and geometric mean diameter( GMD) of soil aggregates,and decreased the destruction rate of aggregate,which could improved the soil structure stability and increased soil aggregates contents in semiarid regions.

关 键 词：轮耕 团聚体 平均重量直径 几何平均直径 土壤容重 土壤孔隙度 

分 类 号：S152.4[农业科学—土壤学]