基于RCSODS的直播水稻精确施氮模拟模型

A RCSODS based-Simulation Model for N Fertilizer Application in Precision Farming for Direct-seeding Rice

遵照“因天、因地、因苗精确施肥”的原则 ,将江苏省农科院研制的 RCSODS(水稻栽培模拟优化决策系统 )改造为适合“上海精准农业园区”的直播水稻精确施 N模拟模型。该模型利用园区的土壤空间信息资料 ,首先可确定不同小区的土壤供 N量 (N Sj) ;然后根据产量目标 ,可确定各小区的水稻需 N量 (N Rj) ,进而确定施 N量的初值 (N Ij) ;将 N Ij输入经改造的 RCSODS,可模拟不同小区各生育阶段的 L AI动态 ,以之与同期适宜 L AI指标作比较 ,可进一步决定水稻的长势因子 (FG) ;最后 ,以 FG对水稻施 N量的初值进行订正 ,即可确定不同小区适宜的施 N量。检验结果表明 :该模型有较好的模拟精度。

Following the principle that “fertilizer should be applied variably depending on weather, soil and crop status”, a simulation model of N fertilizer application, which adapted for the Shanghai Precision Farming Garden for direct seeding rice was developed, based on the Rice Cultivational Simulation, Optimization and Decision making System(RCSODS) by Jiangsu Academy of Agricultural Sciences. In terms of this model, the capacity of N supply for each plot, NS j , can be estimated first using the soil information measured, then the N requirement for each plot, NR j, can be determined, based on the rice yield object. The difference of NR j and NS j gives the initial rate of N fertilizer applied( NI j ). Next, the dynamic of leaf area index for each plot ( LAI j ) can be simulated by the modified RCSODS with a correction factor of N, then the growth status coefficient ( F G) can be obtained by comparing the simulated LAI with the optimum LAI. Finally, the optimum rate of N fertilizer applied can be determined by F G multiply NI j .