红火蚁入侵草坪过程中蚂蚁类群变动趋势

观察研究了红火蚁入侵草坪之后蚂蚁群落结构的变动趋势。对各处理区在不同时期的蚂蚁优势种进行了分析,结果表明,与对照区相比红火蚁入侵后各处理区的蚂蚁优势种发生了明显改变,红火蚁替代了原来的优势蚂蚁种类,并在数量上占主导地位,而且各处理区的蚂蚁类群多样性、均匀度降低,优势度明显增大。通过分析红火蚁入侵过程中各处理区的蚂蚁类群相似性,表明轻度发生区与对照区的蚂蚁类群相似性系数q一直处在0.25-0.50之间,为中等不相似;中度发生区与对照区的蚂蚁类群相似性系数q一直处在0.075-0.444之间,为中等不相似或极不相似;重度发生区与对照区的蚂蚁类群相似性系数q一直处在0.0-0.222之间,为极不相似,这也说明了不同的红火蚁危害程度对本地蚂蚁类群结构的影响是不同的,红火蚁种群数量越大,对本地蚂蚁类群的影响也越大,排挤或取代它们所需要的时间也越短。

Dynamic of native ants on the lawn with the invasion of Solenopsis invicta Buren

After the red imported fire ant (RIFA), Solenopsis invicta Buren was introduced to the lawn, it could settle down and enlarge its population in a short time. RIFA could change the structure of ant community in this invasion area. Through the analyses of predominant ant species in every different invasion periods, the predominant ant species in treatment was different from that in CK. RIFA could substitute for former predominant ant species after its invasion, and had an absolute predominance in population. The results showed that when RIFA invaded the lawn, the ant community diversity index and evenness index declined, and the predominance index in this area was rising. Ant community similarities in each treatment were compared, and it was found that in the area where RIFA slightly invaded and the CK, the comparability coefficient (q) was between 0.25 to 0.50, which was not similar. The comparability coefficient (q) for the area with moderate RIFA and the CK, was between 0.075 and 0.444, which was a middling dissimilar or extraordinarily dissimilar; And that for the area which serously invaded and CK, the comparability coefficient (q) was between 0.0 to 0222, which was extraordinarily dissimilar. It was showed that different endangered districts had different effects on the native ant community. The bigger the population of RIFA was, the greater effect on native ant community it had, and the less time it took for the RIFA to substitute for native ant species.