基于能量模型的水稻生长模型

Rice Growth Model Based on Energy Model

该文考虑生命活动与物质交换和能量流动的关系,从热力学出发,引入一维能量模型。在一维能量模型的基础上,将水稻对外界能量的摄取能力与水稻生长季中的气温变化规律联系起来,建立在气温变化条件下水稻的生长模型。结合气温增长率、水稻最适气温和不同阶段的生物量,以徐士良单形调优算法为基础,利用Forcal二维方程参数拟合,得到关于水稻自然增长率、气温波幅和初始值等参数的最优拟合。将最优拟合数据代人水稻的生长模型,拟合得到水稻的生长曲线和水稻生长随气温的变化趋势。以水稻的生长模型为基础,定性分析水稻的临界气温和最大生长率出现时间。通过分析发现,水稻生长季的临界气温与气温增长率无关;水稻的最大生长率出现时间为水稻分蘖后期、孕穗期。为考虑异常气温对水稻生长的影响,利用Matlab对水稻分蘖期低温和生殖生长期高温的水稻生长进行模拟,结果表明:水稻后期高温对产量影响比前期受低温影响严重。

The one-dimensional energy model is introduced from thermodynamics, considering relationship a- mong the life activity, the mass exchange and energy flow. On the basis of the one-dimension energy mod- el, rice growth model with temperature change is built, linking intake capacity of rice on the outside and temperature variation in growing season. Combined with temperature increasing rate, the optimal tempera- ture and the biomass in different stages, and the optimal fitting of parameters is obtained, which is about natural growth rate of rice, temperature amplitude and initial values, with Xu Shiliang simplex optimiza- tion algorithm and two-dimensional equation parameter fitting of Forcal. The growth curve and trend along with the temperature change are obtained, through the optimal fitting data into the rice growth model. And rice critical temperature and occurrence time of maximum growth rate are analyzed. It＇s found that the critical temperature is unconcerned with the temperature of rice growth rate, illustrating the critical temperature of rice is the natural disposition. The occurrence time of maximum growth rate is found to be the heading stage of rice. To investigate the abnormal temperature effects on the growth of rice, rice growth is simulated with lower temperature in tiller stage and higher temperature in the reproductive growth stage, and the rice growth trend is achieved under the two abnormal temperature conditions, taken Matlab as the numerical analysis tool. Through numerical comparison, the following conclusion is drawn. The impact of high temperature on rice in the later stage is more severe than the impact of low temperature on rice in the earlier stage. The result shows that meteorological disasters in the later stage of rice growth has a direct impact on the yield, while the impact of disaster in the earlier stage can be made up later. By means of numerical analysis and qualitative analysis methods, the growth of rice is analyzed in detail. And some scientific basis is provided for rice yield prediction and impact assessment of temperature on rice bio- mass. This energy model is superior to some traditional pure mathematics model without biological mean- ing, and it also can be used to analyze agricultural ecological chain effect mechanism. At the same time, the consideration of combining mathematical biology and climate condition provides reference for future ec- ological meteorology research.