大中小型拖拉机压实对土壤坚实度和大豆产量的影响

Effects of soil compaction by various tractors on soil penetration resistance and soybean yields

探讨农业机械压实对土壤坚实度和产量的影响规律,对改善作物生产环境、促进农业机械化向质量型转变具有重要意义。以东北典型黑土区耕地土壤为研究对象,依照随机区组试验原理,选择大、中、小3种型号拖拉机进行6种压实处理,同型拖拉机相同压实次数试验重复3次,采用PV6.08型贯穿阻力仪测量压实轮辙截面土壤坚实度。试验结果表明:土壤坚实度随压实次数增加而逐渐递增,3种拖拉机压实测试截面浅层均出现明显压实核,且压实核内土壤坚实度随压实次数增加而逐渐增大,CASE-210型拖拉机压实对表层土壤坚实度影响程度和范围最大,压实12次时压实核处土壤坚实度达4.0 MPa,JD-280型拖拉机对深层土壤压实影响程度和范围最大,在65~80 cm的土壤深层坚实度的峰值达3.2MPa;拖拉机压实均导致大豆产量降低,CASE-210、JD-904和JD-280拖拉机压实12次时大豆产量分别降低了21.24%、18.15%和12.38%。

It has great significance to discuss regularities of soil penetration resistance and crop yield impacted by agricultural machinery compaction to improve crop growing environment and promote the transformation of agricultural mechanization from quantitative type to qualitative type.Taking the cultivated soil in the typical black soil area in northeast China as the research object,three types of tractors were selected,namely large(CASE-210),medium(JD-904) and small(JD-280),the compaction times were designed as 2,4,6,8,10 and 12 times according to the actually situation of agricultural mechanization.The compaction test for each type of tractor with the same compacting times was set to be repeated for three times,and the concrete compaction treatment for the same type of tractor was distributed in different testing plots of different testing column according to the principle of random block test to eliminate the error of tested data caused by soil differences in different plots.Soybean was planted in the field,and PV6.08 penetrative resistance meter was used to measure the soil penetration resistance at sections just across the compaction rut during the growing period of soybean.The error data were identified and removed based on the 3σ criteria and Matlab(R2016 b) program.Effective software such as Sufer12.0 et al.were used to draw the contour map of soil penetration resistance at the cross section in each testing plots of different treatment.Harvested soybean grain was dried according GB5009.3-2016 to calculate grain moisture content,and soybean yield of each treatment was calculated under the standard soybean moisture content,and the significance of soybean yield differences of each treatments were also analyzed so as to explore the change rule of soybean yield.The results showed that the soil penetration resistance increases gradually with the increase of compaction times,and there were obvious compaction cores in the compacted sections of the three tractors,and core soil penetration resistance increased with the increase of compaction times,the compaction of CASE-210 tractor had the greatest influence on the surface soil where the maximum penetration resistance was 4.0 MPa when compacted 12 times.The compaction of JD-280 tractor had the greatest influence on soil at the depth of 65-80 cm where the maximum penetration resistance was 3.2 MPa when compacted 12 times.At the same time,the tractor compaction led to the decrease of soybean yield and it was most significant when compacted 12 times.The soybean yield at the plots decrease rates were 21.24%,18.15% and 12.38% when compacted 12 times by CASE-210,JD-904 and JD-280 tractors.