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以新疆绿洲玛纳斯河流域连作20年棉田土壤为研究对象,采用微区控制试验,分析连作棉田(CM)、轮作玉米(YL)、轮作大豆(DL)、玉米/大豆间作(YDJ)和休闲免耕(XX)5种植模式对土壤团聚体组成及有机碳分布特征的影响,结果表明:土壤粒径在53~250um机械稳定性团聚体含量在5种植模式中均为最高,所占比列为39%~53%,而粒径53~250um的水稳性团聚体含量最少。粒径>250um机械稳定性团聚体含量为DL>YL>XX>CM>YDJ,水稳性团聚体为CM>YL>DL>YDJ>XX。作物收获期DL和YDJ的团粒指数比生长前期分别减少18.7%和16.6%。土壤团聚体有机碳主要集中在粒径>250um的大团聚体中,而<250um微团聚体中含量较少。不同模式中土壤有机碳含量为DL>YL>CM>XX>YDJ。比较4种轮作模式,大豆轮作和玉米轮作有利于团聚体的形成和稳定,可作为轮作倒茬的种植模式。
Taking 20 years of continuous cropping cotton soil in Manas River basin in Xinjiang oasis as research object, this paper analyzed the effects of continuous cropping cotton (CM), rotation of maize (YL), crop rotation of soybean (DL), maize / soybean intercropping The results showed that the content of aggregates with mechanical stability at 53 ~ 250um was the highest among all the five planting patterns, and the proportion of leisure-tillage (XX) 5 planting pattern on the composition of soil aggregate and the distribution of organic carbon Listed as 39% ~ 53%, while the particle size of 53 ~ 250um water-stable aggregates content of at least. Particle size> 250um Mechanical stability Aggregate content DL> YL> XX> CM> YDJ, water stable aggregates CM> YL> DL> YDJ> XX. The aggregate index of DL and YDJ at the harvest stage decreased by 18.7% and 16.6% respectively compared with the pre-growth stage. Organic carbon in soil aggregates mainly concentrated in large aggregates> 250 um in size, but less in <250 um microaggregates. Soil organic carbon content in different patterns was DL> YL> CM> XX> YDJ. Comparing the four cropping patterns, soybean rotation and corn rotation are favorable for the formation and stability of aggregates, which can be used as crop rotation patterns.