土壤机械压实及其对作物生长的影响

在生产中农业机械替代人畜力从事农业生产劳动是必然的趋势。随着农业机械化水平的快速提高,土壤机械压实问题越来越突出。通过分析土壤机械压应力传递模型,以及土壤压实后土壤容重、坚实度增加,孔隙度、含水量降低,土壤的渗透性变差等土壤质量恶化现象,发现土壤压实可导致土壤质量下降,抑制作物的根系生长发育,对作物吸收土壤中的水分、养分产生不利影响。可造成玉米减产9.5%~14.4%,小麦减产4.0%~20.0%,大豆减产3.8%~13.4%,甜菜根产量降低5.81%~24.13%,含糖率降低0.49~0.81ºZ。因此,在农业生产中必须要重视土壤压实问题,采取切实可行的技术措施,减轻农业机械化作业对土壤造成的负面影响,促进作物生长,提高农艺综合效益。

Soil Mechanical Compaction and Its Effect on Crop Growth

It is an inevitable trend that agricultural machines are replacing human and animal power in agricultural production. The soil mechanical compaction problem has become more and more prominent with the rapid improvement of agricultural mechanization level. In this study, we analyzed the stress transfer model of soil mechanical compaction and the deterioration of soil quality after the mechanical compaction such as the increase of soil bulk density and firmness, and the decrease of porosity, moisture content and permeability. It is found that soil compaction could lead to soil quality deterioration to inhibit the root growth and development of crops, and cause an adverse effect on the absorption of moisture and nutrients. It is estimated that soil mechanical compaction in agricultural production could reduce the yield of maize by 9.5%-14.4%, of wheat by 4.0%-20.0%, of soybean by 3.8%-13.4%, and of sugar beet root by 5.81%-24.13%, and sugar content of sugar beet by 0.49-0.81°Z. Therefore, sufficient attention must be paid to the soil compaction in agricultural production, and feasible technical measures should be taken to reduce the negative impact of agricultural mechanization on soil, promote crop growth and improve the comprehensive benefits of agriculture.