摘要
在位于黄河流域半干旱区清水河县,设置免耕不同轮作方式对土壤物理性质及作物产量的影响试验。对免耕不同耕作方式下,土壤团粒结构、总孔隙度、水热变化及作物产量进行了测定。结果表明：经3 a的免耕＋轮作后,土壤团粒结构,总孔隙度和水分含量均有逐年增加的趋势,其中留茬覆盖处理尤为明显。秸秆覆盖处理土壤团聚体在0.25-0.5 mm之间含量最高;常规耕作与留茬不覆盖在0.1-0.25 mm之间达到最高值。说明,留茬覆盖有利于形成大粒径的团聚体颗粒,留茬不覆盖处理对于土壤微结构的形成有良好的促进作用。同时,土壤总孔隙度在不同年际间均表现为留高茬覆盖〉留低茬覆盖〉留高茬〉留低茬〉常规耕作,可见,免耕不同轮作方式对土壤的改善有一定的积极作用。实施免耕的前2 a,作物产量不稳定,甚至造成减产,第3年免耕增产效应有所显现。
An experiment about the effects of different methods of crop rotation under no-tillage on soil physical properties and crop yields had been carried out in Qing Shuihe County in semiarid area of the Yellow River valley.Soil aggregate structure,total porosity,climate evolvement of water-heat and crop yields were determined.The results showed that after three years of no-tillage and rotation,soil aggregate structure,total porosity and water content all increased year by year,especially the treatment of stubble mulching.The amount of 0.25～0.5 mm soil aggregates is the largest under straw mulch, while the highest value is in 0.1～0.25 mm soil aggregates under conventional tillage and stubble without mulch.It showed that stubble mulch was helpful to form macro-aggregates;Stubble without mulch had a large improvement in soil microstructure-forming.At the same time,soil total porosity in different years revealed an order from bigger to smaller,which ranks as follows： high stubble with mulch,low stubble with mulch,high stubble,low stubble,conventional tillage.It was concluded that different methods of crop rotation under no-tillage had a positive effect on improvement of soil.During the first two years of no tillage,crop yield was unstable;but in the third year,the yield was increased.
出处
《干旱地区农业研究》
CSCD
北大核心
2010年第5期38-42,共5页
Agricultural Research in the Arid Areas
基金
国家"十一五"科技支撑计划重点课题(2006BAD15B05)
中国农业大学与内蒙古农业大学两校合作基金项目
挑战计划项目"黄河流域旱作保护性农业研究"
国际玉米小麦改良中心(CIMMYT)
