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依据对棉铃虫自然种群生命表研究所获得的种群统计参数,采用蒙特卡罗方法,模拟了随机环境条件下的棉铃虫种群发生动态。模拟结果显示,同一输入参数(模拟的1代残虫量),经过确定世代或生活史阶段后,棉铃虫的种群密度既可能为轻发生,也可能种群暴发。环境条件有利时,输入变量(模拟的1代残虫量)影响棉铃虫最大可能的发生程度。当棉铃虫为中等或轻发生时,1代残虫量(模型输入参数)和最终的棉铃虫发生程度(模型输出)没有明显的依赖关系。相同的最终棉铃虫发生程度所对应的模型的输入变量可以有多种水平。模拟结果显示,在环境条件比较有利情况下,棉铃虫只需要1个世代或某一个生活史阶段(如蛹期),种群密度即可达暴发水平。本文的研究结果说明,对棉铃虫中长期发生态势的预测,存在一定程度的不确定性。
Based on the population statistics obtained from the study of the natural population life table of cotton bollworm, the population dynamics of cotton bollworm were simulated under the random environment using Monte Carlo method. The simulation results showed that the population density of cotton bollworm may be either light or outbreak after the same input parameters (the first generation of the simulated amount of the parasites) after the determination of generation or life stage. When the environmental conditions are favorable, the input variables (the simulated first-generation residual amount of earthworms) affect the maximum possible occurrence of H. armigera. When the bollworm was moderate or light, there was no significant dependence on the amount of first-instar larvae (model input parameters) and the degree of occurrence of the final bollworm (model output). The input variable for the model corresponding to the degree of occurrence of the same final bollworm can have a variety of levels. The simulation results showed that under the condition of favorable environmental conditions, the cotton bollworm only needs one generation or one life history stage (such as pupal stage), and the population density can reach the outbreak level. The results of this study show that there is a certain degree of uncertainty in predicting the long-term occurrence of cotton bollworm.