土膜耕作法的土壤与作物效应研究OA北大核心CSTPCD

[Objective]To make clear the agricultural productive value of soil film tillage,the effects of soil film tillage on soil moisture,temperature and nutrient changes in farmland were explored,and the effects of soil film on crop root growth and yield were revealed too,so as to provide the theoretical basis and technical methods for the application of soil film.[Method]Soil film was induced by spraying a 1.0%concentration of carboxymethyl cellulose ammonium(CMC-NH4)aqueous solution,and the field experiment was conducted with five treatments,including 0(CK),50.0(T1),100.0(T2),200.0(T3),and 300.0 kg·hm-2(T4).The effects of CMC-NH4 application rate on soil moisture,temperature,nutrients,microorganisms,crop roots and yield in multiple cropping of spring wheat and summer maize were studied.[Result]Soil film treatment of spring wheat and summer maize could increase average daily soil moisture content by 3.3%-7.0%(P＜0.05,the same as below)and 1.9%-6.1%,average daily temperature by 7.9%-12.6%and 5.6%-11.7%,contribution of soil accumulated temperature of growth period by 88.98-141.94℃and 60.25-136.65℃,root length of 0-30 cm soil layer by 37.5%-17.1%and 11.2%-1.7%,root surface area of 0-30 cm soil layer by 15.3%-4.5%and 12.5%-9.2%,respectively,and root biomass(dry weight)in 0-30 cm soil layer were enhanced by 17.0%-41.5%and 30.9%-36.7%,respectively.Finally,the grain yield of spring wheat per unit area was increased by 7.3%-18.8%and above-ground dry weight of summer maize per unit area was increased by 33.6%-49.0%.and the soil nitrogen,phosphorus and potassium content as well as soil microbial diversity were improved too.[Conclusion]As a novel type of soil tillage,soil film had the function of farmland coverage,which greatly contributed to improve soil hydrothermal environment,and promote nutrient absorption and utilization,root growth and crop yield.At the same time,soil film produced the important technique and method to make the better plough layer structure that is"compact surface,loose top and tight bottom of plough layer",which would support the improvement of crop productivity,farmland soil amendment and agricultural high-quality development.In this study,the recommended application rate was 100.0 kg·hm-2 in Ningxia Yellow River irrigation area.