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1.种群增长的估计为了帮助理解昆虫与环境之问的关系对种群增长的作用,首先考虑一个最简单的种群增长模型可能是有益的。这就是人们称为的指数模型,并且假定对种群增长完全没有限制。模式为 Nt=N_oe~(rt)。这里 N_o 是在时刻0时的种群数量,Nt 是在时刻 t 时的种群数量,r 是自然内在增长率。后一项表示纯粹是由出生率和死亡率的作用。这一模型预示种群数量增长表现为指数函数的轨迹(图1)。
1. Estimation of population growth To help understand the role of insects and the environment in relation to population growth, it may be beneficial to consider one of the simplest models of population growth first. This is what we call the exponential model, and assumes there is no limit to population growth. The mode is Nt = N_oe ~ (rt). Where N_o is the population number at time 0, Nt is the population number at time t, and r is the natural internal growth rate. The latter one is said to be purely a function of birth rate and mortality. This model predicts that population growth will behave as an exponential function (Figure 1).