昆虫种群系统的能控性和能观性

能控性和能观性是工程控制论中２个重要的新概念，它们在研究动物种群系统时是很有用的．昆虫种群系统是由对象种群和影响该种群的环境因素组成的，因此，只有当影响对象种群的输入变量（如死亡因子）是可控的，整个系统才是能够控制的；只有当与系统内部状态有关的输出变量（如昆虫的发育阶段）是可观的，整个系统才是能够观测的．本文在描述动态系统状态空间模型的基础上，简述了系统能控性和能观性的概念及其充分和必要条件，同时运用这２个基本概念及其分析方法研究了云杉卷叶蛾种群系统的能控性和能观性问题．结果表明，满足云杉卷叶蛾种群系统能控性的充分和必要条件是系统的输入变量（防治对策）必须对种群的各个虫态或龄期起到控制作用，因为一种防治对策如果只能控制一个虫态或龄期，其余虫态或龄期的数量仍然得不到控制而任意波动，在这种情况下，该系统就是不可控系统．云杉卷叶蛾种群系统是能观系统，因为该系统的内部状态与输出变量有联系，有关种群动态的信息可以通过各个虫态或龄期来观测．研究昆虫种群系统的能控性和能观性，是寻求系统优化控制对策的必要前提

Controllability and Observability in Insect Population Systems

Controllability and observability, two important concepts in engineering cybernetics, are useful in studying animal population systems. An insect population system is comprised of: 1) the subject population and 2) the environment factors affecting the pupulation. If the whole system is to be manipulated, the input variables (such as mortality factors) that affect the population must be controlled. Similarly, information necessary for understanding the internal system, is seen through the output variables (such as insect life stages) of that system. Based on the state space model of a dynamic system, the present paper gives a short review of the concepts of controllability and observability and of some necessary and sufficient conditions which the system must fulfil in order to have these properties. An application of these conceps to the population system of spruce budworn, Choristoneura fumiferana (Clemens), is shown. Controllability of this system requires that the input variables (mortality factors) have an effect on all life stages. If a given control strategy affects only the mortality of one life stage, it is difficult to manipulate the population because the other stages will remain fluctuate. This system is observable because all information about its population dynamics can be obtained from visible life stages. Thus, controllability and observability of an insect population system must be analyzed before developing an optimal management strategy.