表土处理对大豆田土壤团聚体特征及产量的影响

Effect of Topsoil Treatment on Characteristics of Soil Aggregates of Soybean Field and Soybean Yield

为揭示在常规耕作制度基础上大豆田表土处理对表层土壤物理性状及产量的影响,试验采用大区对比法,设置2个处理(T1:当地常规耕作措施;T2:当地常规耕作措施+表土破碎处理),研究表土处理对0~30 cm土壤温湿度、容重、孔隙度、水稳定性团聚体及大豆产量的影响。结果表明:T2处理显著降低0~10 cm土层容重,降幅6.0%~13.8%,显著提高0~10 cm土层孔隙度,增幅3.83%~8.40%,降低5~15 cm土层的温度,降幅0.2~1.3℃,提高5~15 cm土层的湿度,增幅0.1%~1.5%;显著增加大团聚体(R>0.25 mm)数量,增幅9.02%~20.30%,增加土壤水稳定性团聚体的平均质量直径(MWD)与几何平均直径(GMD),其中MWD和GMD增幅分别为4.25%~6.58%和28.4%~30.3%,产量提高6.24%。结果表明,常规耕作措施结合表土破碎处理能够降低表层土壤容重,增加表层土壤孔隙度,增加土壤大团聚体数量,增加土壤水稳定性,可为作物的生长提供较良好的土壤环境。

In order to demonstrate the effect of conventional tillage system with topsoil treatment on the soil physical properties and soybean yield, adopting the method of regional contrast, setting two treatments （T1 represents local conventional tillage measures, T2 represents conventional tillage measures ＋ topsoil soil crushing treatment） to analyze the influence on soil tem- perature and humidity, the bulk density, porosity, water stability, the aggregate in 0 -30 cm soil depth and soybean yield. The results showed that T2 treatment significantly decreased 0 - 10 cm soil bulk density with a decline of 6% to 13.8%, sig- nificantly increased the porosity of soil layer between 0 - 10 cm, with 3.83% to 8.40%, reduced 5 - 15 cm soil temperature with a decline ofO. 2 to 1.3 centigrade, improve 5 - 15 cm soil moisture with an increase from 0. 1% to 1.5%, significantly increase the number of large aggregate （R 〉0. 25 ram） by 9. 0% to 20. 3%. The mean weight diameter（MWD） and the geo- metric mean diameter（GMD） of soil water stability agglomeration increased by 4. 25% to 6. 58% and 28.4% to 30. 3% re- spectively, while soybean yield increased by 6. 24%. The results showed that topsoil crushing treatment could reduce topsoil bulk density, increase topsoil porosity, increase soil bulk aggregate number, increase soil water stability and provide a better soil environment for crop growth.