猎物密度对七星瓢虫与异色瓢虫种间竞争的影响

通过单种群与混合种群饲养,研究了猎物密度对七星瓢虫Coccinella septempunctata和异色瓢虫Leis axyridis种间竞争影响,并用Lotka-Volterra种间竞争模型对两种瓢虫在猎物相对充足与不足条件下的种间竞争进行模拟,结果表明:猎物充足,两种瓢虫的种群增长呈线性增长趋势;猎物不足时,单独饲养时,两种瓢虫的种群增长趋势呈Logistic曲线,混合饲养时异色瓢虫的种群增长呈上升趋势,七星瓢虫趋于下降。在两种瓢虫的种间竞争中,异色瓢虫占相对优势,竞争的结局是二者可以形成一个稳定的平衡局面而得以共存。

The influences of interspecies competition between Coccinella septempunctata and Leis axyridis on the density of preys

The influences of interspecies competition between Coccinella septempunctata and Leis axyridis were studied under the condition of single rearing and mixed rearing,and Lotka-Volterra equation was used to simulate the competition when more preys and less preys provided for the two ladybirds.The results showed that the population growth trendency of the two ladybirds was linear when the preys were sufficient,but if lack of preys,the tendency was Logistic curve when by single rearing;and the population growth tendency of C.septempunctata was dropping,the population of L.axyridis was raising when lacking of preys.In the competition system of the two ladybirds,L.axyridis was dominant,but C.septempunctata could exist simultaneously.