A Research For Maize/Soybean Intercropping Mode Optimization Based On Virtual Plants Model

Intercropping between crops has been a hot topic in domestic and international research, and intercropping distance is the main factor which affects land utilization. Therefore, a high utilization rate of the intercropping distance is widely concerned with. In the intercropping distance research, the traditional field experiment can provide the direction and reference for intercropping distance optimization, but this method is time-consuming and tedious, and cannot be applied to quantitative interspecific distance quickly and targeted. In the process of the intercropping distance optimization, therefore, how to further reduce the manual operation, more automatically and quickly get the optimal planting distance in a specified domain, has become a big concern for researchers in this field.In this paper, an optimization algorithm is applied to the optimization of intercropping distance of maize/soybean, which based on intercropping of maize/soybean functional-structural model. Our paper can provide new ideas of intercropping for scholars who study about intercropping models, and also give users a reasonable suggestion about intercropping planting. Thus, our work has important theoretical significance and practical value. The main work of this paper are shown as follows:1. A maize and soybean morphology model is established. Firstly, we analyse the morphological characteristics of maize and soybean, and separate each organ from the maize and soybean; Secondly, the organs of the three-dimensionalshape is built which are based on the organ morphology characteristics. Then a method to model soybean pods is proposed based on the NURBS surface. Finally,a 3D visualization model of Maize/soybean is set up, and this model is based on the XL language which can describe the single plant and intercepted plants’ topology of maize/soybean.2. A functional-structural model of intercropping maize/soybean is established.First of all, based on the maize and soybean morphology model, the canopy light distribution of a maize and soybean plant can be obtained. Combined with the characteristic of morphology, we utilize the algorithm of light interception on the GroIMP platform. Then, according to the light interception, the effect of the production and distribution of canopy photosynthetic to the growth of each organ is calculated. And the influence of organs reconstruction to the morphological structures of plant is studied. A intercropping of maize/soybean functional-structural model is set up to implement the simulation of maize and soybean growth process, according to the feedback of the canopy biomass production, biomass allocation and organ growth.3. A method to optimize maize/soybean intercropping distance is proposed.The algorithm is based on intercropping of maize/soybean functional-structural model. In the specified intercropping ratio(such as intercropping between maize and soybean under is 1:2),we use a exhaustive algorithm to change its position continuously and get the entire distance combinations with corresponding light interceptions in the specified threshold, then input these date into tables. By sorting the tables, we can figure out the optimal distance combination in the specified threshold.