红火蚁入侵对人为干扰区蚂蚁群落结构及多样性的影响

Effects of the red imported fire ant, Solenopsis invicta Buren, on the structure and diversity of the ant community in a human disturbed area

【目的】研究红火蚁Solenopsis invicta Buren入侵人为干扰区域后对本地蚂蚁群落建立及物种多样性的影响,为有效控制红火蚁进一步扩散蔓延提供科学依据。【方法】以广州市花都区花东镇保良村安置区为典型案例,调查研究了安置区外围(非人为干扰区)、安置区(人为干扰区)内的楼房区、草坪绿化地、荒地3种生境的蚂蚁种类和数量,分析其群落结构及多样性指数。【结果】(1)安置区外围诱集到25种蚂蚁,以黑头酸臭蚁Tapinoma melanocephalum Fabricius、褐大头蚁Pheidole megacephala Fabricius为优势种,而在安置内仅诱集到13种,红火蚁占绝对优势;红火蚁入侵定殖显著降低了安置区内蚂蚁种群的多样性、均匀度和丰富度,而优势度及优势集中性指数却显著升高,其对安置区外围的农业生态系统影响较小。(2)安置区内草坪绿化地、荒地生境中红火蚁的比例占90%以上,而在楼房区中红火蚁的比例仅为29.11%;红火蚁在草坪绿化地、荒地的优势种占绝对优势,其优势度指数、优势集中性指数与楼房区差异极显著;在安置区内,红火蚁在人类极少活动的荒地发生较重,偶尔活动的草坪区发生次之,经常活动的楼房区极少发生。【结论】入侵红火蚁与本地蚂蚁在人为干扰区共同定殖时,红火蚁入侵显著降低了人为干扰区内的蚂蚁群落多样性,但其红火蚁的发生程度与人类日常活动呈反比。

[Objectives] In order to provide a scientific basis for better control of the fire ant, the effects of Solenopsis invicta Buren on the structure and diversity of an ant community were studied in a human disturbed area. [Methods] Ant species diversity and abundance were investigated in an outside resettlement area （non human disturbed area） and an inside resettlement area （human disturbed area, including dwelling area, grass lawn and barren land）, in Baoliang Village, Huadong Town, Huadu District, Guangzhou City, and the community structure dominant species, species diversity, evenness and richness index of the ant community determined. [Results] （1） 25 ant species were collected in the outside resettlement area where Tapinoma melanocephalum Fabricius and Pheidole megacephala Fabricius were the dominant species. 13 ant species were collected in the inside resettlement area where S. invicta was the dominant species. Colonization by S. invicta significantly reduced the diversity, evenness and richness of the ant community within the resettlement area, while the dominance index and the dominance concentration index of the ant community significantly increased compared to that of the community in the outside resettlement area, where S. invicta had a limited impact on the agricultural ecosystem. （2） The proportion orS. invicta in the ant community was more than 90% in grass lawn and barren land, but only 29.11% in dwelling areas. S. invicta was the dominant species in grass lawns and barren land, and there were significant differences in the dominance index and dominance concentration index between ant communities in grass lawn and barren land and those in dwelling areas. S. invicta was most abundant in scarcely-disturbed barren land, followed by occasionally disturbing grass lawn, but was only lightly distributed in frequently disturbing dwelling areas. [Conclusion] During simultaneous colonization by invasive and native ant species, the invasive ant S. invicta significantly reduced the diversity of the ant community in a human disturbed area. The occurrence of S. invicta was inversely proportional to the level of disturbance caused by daily human activity.