| 摘要: |
| 仅考察降雨对棉蚜的机械杀伤作用时,一日降雨量(R)与棉蚜死亡率(D)之间呈“S”型曲线关系。利用正态分布的积分面积与正态等差的关系,可将死亡率换算为机率值(p),便有p=a+bR线性方程。再将单位脉冲函数δ(t)及t时刻棉蚜种群M(t)引入方程,并对p与D的关系换算,可得降雨杀死棉蚜的动态模型 T(t)=δ(t).M(t).(1-D) |
| 关键词: 棉蚜,降雨因子,脉冲函数 |
| DOI： |
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| A MODEL OF RAINFALL INFLICTING CASUALTY UPON COTTON APHID POPULATION |
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WangShize Zhang Wenjun
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| Abstract: |
| Only through examining the effect of rainfall inflicting casualty upon
the cotton aphid population,there exists an S-shaped curve between
rainfall per day (R) and the mortality (D) of cotton aphids.And then
the mortality (D) of cotton aphids can be converted into the value of
probability (P) using the relationship between integral area of normal
distribution and normal equivalent deviation,thus,obtaing the linear
equation: P=a+bR.
And then the pulse function.δ(t) per unit area and cotton aphid population M(t) at t time can be introduced into the equation,and the values
of P and D can be converted.Thus far,a dynamic model of rainfall inf1icting casuaty on cotton aphid population is deduced as follows: T(t)=δ(t).M(t).(1-D) |
| Key words: cotton aphid, rainfall factor, pulse function |
