Research On Productivity、Ecological Environmental Effect And The Characteristics Of Energy-nutrient Flow Under The Multiple Cropping Rotation Systems

Jiangxi province was the typical double rice region in the south of China, ranked thefirst in the proportion of double-crop cultivation, played an important role in riceproduction in our country. Multiple croppping rotation system was an important measurefor agricultural development cycle, to meet the needs of the strategic adjustment ofagricultural structure, studyed the effects of Jiangxi paddy under the multiple rotationsystem, which had the great importance of the sustainability of China southern croppingproduction and food security. In this study, based on the2-year field experiment, studyedthree aspects of crop productivity, ecological environmental and the characteristics ofenergy-nutrient flow, the results showed that:1. Paddy multiple cropping rotation could improve crop productivity. Multiplecropping rotation tiller number, plant height, leaf chlorophyll content, the effect on thedynamic roots and dry matter accumulation were better than continuous cropping treatment,and helped to promote crop growth,development and population growth, which had adefinite impact on the yield and composition of factors. Early rice yields were lower thanthe yield of late rice; the rotation treament rice yield was higher than continuous croppingtreatment. From the constituent elements of the production point of view, most of theindicators were rotation processing was superior to continuous cropping treatment. Thepaddy multiple cropping rotation was the most significant, the most stable, and an effectiveway to maintain the sustainable of southern rice fields and a cultivation method to bepromoted.2. Paddy cropping rotation could improve the ecological environment effects. Ricepaddies multiple cropping rotations was conducive to the improvement of the soil physicaland chemical properties. With the increase of years of crop rotation, soil bulk densitydecreased, the total porosity increased, and increased soil pH, soil organic matteraccumulation, soil nutrients N, P, K, the soil microbial quantity and enzyme activitycompared continuous cropping treatment. Paddy crop rotation could reduced the hazards ofpests of rice for rice, rotation of rice pests were lower than cropping rice fields.3. Paddy cropping rotation system should improve the the farmland ecosystem energyflow and material recycling. Gross primary productivity, the total investment of energy,solar energy utilization, and auxiliary energy output ratio of paddy crop rotation processingwas higher than the continuous cropping. N, P, K nutrient utilization was also significantlyhigher than cropping and rotation system of N, P prime showed a surplus of state, was apositive state of equilibrium, was conducive to soil N, P prime virtuous circle. K inputsystem was less than K within the system output, K there was a serious loss.