红火蚁与双齿多刺蚁竞争性研究

Competitive Study Between Solenopsis invicta and Polyrhachis dives

为探明入侵生物红火蚁的竞争能力,本文围绕双齿多刺蚁与红火蚁之间的干扰竞争现象进行观察实验;通过记录两种蚂蚁之间的攻击级别(攻击级别由弱到强分为Ⅰ、Ⅱ、Ⅲ、Ⅳ四级),并运用攻击指数公式与两者之间相对抗的死亡率来评价红火蚁与双齿多刺蚁在个体与群体水平上的攻击强度。结果表明:个体水平攻击测试中,双齿多刺蚁与红火蚁的总体攻击级别占比多为Ⅱ、Ⅳ级,并且随着红火蚁工蚁体型大、中、小的改变,Ⅳ级的攻击级别占比逐渐升高,分别为25.00%、45.00%、60.00%;群体攻击测试中,红火蚁与双齿多刺蚁的数量比例依照5∶1、3∶1、1∶1、1∶3、1∶5进行处理可发现,随着双齿多刺蚁数量的增加,红火蚁的死亡率逐渐升高,当两者数量比例为1∶1时,双齿多刺蚁死亡率为12.00%,红火蚁死亡率为27.33%(t=5.50,p<0.01),可见在同等数量比例的对抗下双齿多刺蚁的死亡率低于红火蚁。综合试验结果可知,双齿多刺蚁对红火蚁的攻击程度较为激烈,该蚁在抑制红火蚁的扩张中起到一定作用。

The interference competition between the two species of ants, Polyrhachis dives and Solenopsis invicta, was observed in an experiment to make sure the competitiveness of S. invicta. The attack levels of S. invicta and P. dives were recorded as levels Ⅰ, Ⅱ, Ⅲ and Ⅳ from the low to high, and the attack severity of the individuals and groups of S. invicta and P. dives was evaluated by using attack index formula and the attack mortality rate of S. invicta and P. dives. The results showed that in the individual attack S. invicta and P. dives were mostly grouped in attack levels Ⅱ and Ⅳ, and that the proportions of S. invicta in attack level Ⅳ increased gradually when the ant workers of S. invicta changed in size, and were 25.00%, 45.00% and 60.00% for the large, middle and small ant workers, respectively. In the group attack where the number of S.invicta and P. dives was in the ratios of 5:1, 3:1, 1:1, 1:3, 1:5 the attack mortality rate of S. invicta increased gradually when the number of P. dives increased, and the attack mortality rate was 12.00% for P. dives and 27.33%(t = 5.50, p < 0.01) for S. invicta when the ratio of P. dives to S. invicta was 1:1, which indicated that P. dives had a lower attack mortality rate than S. invicta when fighting with the same number. It was concluded that P. dives had a higher attack severity than S. invicta, and played a certain role in inhibiting the expansion of S. invicta.