Research On Optimized Mode Of Multiple Cropping Pattern With Corn And Soybean As The Subject In Red Soil Dryland

Jiangxi province is one of the provinces where red soil area is distributed in the south of China.Dryland development and multiple cropping system is one of the main dominant cropping systems in southern China,optimize the allocation of resources in the dry land,crops stable yield,soil fertilization and fertilizer,farmers,agricultural environmental protection and other aspects have important role.This study through the field experiment carried out in Jiangxi Institute of red soil,with the traditional way of monoculture soybean monoculture maize,as control,designed 5 kinds of multiple cropping patterns,research the effects of corn and soybean multiple cropping patterns on crop yield,nutrient utilization,resource utilization and farmland ecological environment,and by using the grey correlation method for comprehensive benefit evaluation,the main conclusions are as follows:1.From the point of crop yield,dryland multiple cropping patterns compared to monoculture pattern,with the promotion of the superiority of the system increase,more full use of water resources of light and temperature,the benefit of annual output has been realized.The “potato / spring corn / summer soybean” model was the best,the mode of “rape-summer corn ∥ summer soybean” took second place.However,the grain yield of maize and soybean intercropping system in this study were lower than the grain yield of corn and soybean monoculture.2.The multiple cropping pattern in dryland red soil,corn and soybean harvest plant N accumulation compared to monoculture decreased,but the nitrogen harvest index of multiple cropping system in maize was higher than that of monoculture maize,nitrogen harvest index of soybean was lower than monoculture soybean,the whole plant nitrogen harvest index system is higher than that of monoculture maize was lower than monoculture soybean.In addition,the nitrogen in red soil dryland multiple cropping pattern of dry matter production efficiency was lower than that of monoculture corn was higher than that of monoculture soybean.“winter fallow-spring corn” model of dry matter production efficiency is the highest,followed by the “rape-summer corn∥ summer soybean” mode.3.From the view of resource utilization,annual light red soil dryland multiple cropping pattern utilization,effective temperature utilization rate,the utilization rate of rainfall was higher than that of monoculture.Among them,the highest rate of the light energy utilization rate and annual precipitation of “rape-summer corn ∥ summer soybean”,has advantages in material production on the anniversary of the best performance,the annual precipitation of “potato-spring corn / summer soybean” mode of utilization after the “rape-summer corn ∥ summer soybean” mode,and “Chinese milk vetch / spring corn / summer soybean” model of the effective temperature the highest utilization rate.4.Red soil dryland multiple cropping pattern compared to monoculture,crop diversity index was higher.In addition,the multiple cropping patterns of red soil dryland can reduce soil bulk density,increase total porosity of soil,improve soil pH and organic matter,and promote soil available N,P and K release,“potato / spring corn / summer soybean” has the best performance.Multiple cropping patterns in dryland red soil can increase soil microbial quantity,improve soil enzyme activity,“potato / spring corn / summer soybean" and “Chinese milk vetch / spring corn / summer soybean” mode is better,and the two models can improve soil carbon pool activity index and carbon management index,has better effect of carbon sequestration.5.The comprehensive benefits of red soil dryland weighted correlation order “rapesummer corn ∥ summer soybean” > “potato / spring corn / summer soybean” > “winter fallow-spring corn ∥ spring soybean” > “winter fallow-spring corn” > “Chinese milk vetch-spring corn / summer soybean” > “Chinese milk vetch-spring corn∥spring soybean” > “winter fallow-spring soybean”,rape-summer corn‖summer soybean” model of the maximum weighted incidence degree,can take into account the three benefits,is the best pattern of corn multiple cropping systems on dryland red soil of yield and income increase,efficiency;“potato / spring corn / summer soybean” followed on red soil dryland maize planting structure optimization has important significance.