太白山锐齿栎树干基部两种蚂蚁的筑巢生态学及其蚁巢、体表真菌组成研究(英文)

The nesting ecology and fungal composition of nests and exoskeletons of two ant species in the basal trunks of Quercus aliena var.acuteserrata in Mt.Taibai,China

本文研究了太白山锐齿栎景观林带树干基部筑巢的两种蚂蚁的筑巢生态学及其巢内真菌的组成。研究结果表明:亮腹黑褐蚁Formica gagatoides Ruzsky是锐齿栎林中的优势蚁种,可在地表及树干上活动,主要取食栎树枝条上蚜虫所分泌的蜜露及其他昆虫和植物材料;盘腹蚁Aphaenogaster sp.仅在蚁巢周围活动,捕食其他小型昆虫;亮腹黑褐蚁F.gagatoides蚁巢材料含水量非常高,而盘腹蚁Aphaenogaster sp.的蚁巢较为干燥。锐齿栎林中树干的平均蚁栖率为20.3%,但蚁栖率随海拔差异而不同(海拔1800m的锐齿栎林带蚁栖率仅为6%,海拔1600m的锐齿栎林带蚁栖率高达38.5%)。两种蚂蚁的长期营巢活动造成树干基部腐朽、孔洞不断扩大,严重影响锐齿栎树干的水分、营养传输及生长,且极易倒伏和风折。两种蚂蚁巢内及其体表真菌的种类组成明显不同,从亮腹黑褐蚁F.gagatoides蚁巢材料中可分离出7种真菌,而从盘腹蚁Aphaenogaster sp.巢中仅分离出2种;从亮腹黑褐蚁F.gagatoides体表可分离出4种真菌,而从盘腹蚁Aphaenogaster sp.体表分离到3种真菌;其中Trichoderma sp.为优势真菌种类。这些真菌与相关蚂蚁的协同进化及其对蚂蚁筑巢和锐齿栎木材分解中的影响作用有待于进一步研究。

The nesting ecology and fungi composition of nests and exoskeletons of two ant species（Formica gagatoides Ruzsky and Aphaenogaster sp.） were investigated,which nest in basal trunks of Quercus aliena var.acuteserrata in Mt.Taibai,China.F.gagatoides is one of the most abundant ant species in the Qurcus forests and mainly feed on other insects,plant material and honeydew of aphids which induce insect galls on slim branches of Qurcus aliena var.acuteserrata.Aphaenogaster sp.was only found in the cavities of Qurcus trunks,and they caught small insects.The nests of F.gagatoides were usually very wet,while the nests of Aphaenogaster sp.were relatively drier.The percentage of ant-habitat trees is about 20.3% on average and varied in relation to altitudes,i.e.,from 6 % at least（in woods of altitude of 1800 m） to 38.5% at maximum（in woods of altitude of 1600 m）.The nesting activities of the two ant species cause strong biodisturbance damage to Qurcus aliena var.acuteserrata：1） they greatly affect water and nutrition transport and cause wood decay in stems of the oaks;2） the significantly damaged trees are structurally weakened and likely to break during windstorms or harvesting operations;3） they affect eventually the vegetation succession and nutritional recycle of sight woods of Quercus.Moreover,the fungal communities in nests and on exoskeletons of the two ant species were clearly different,and seven fungi were isolated from the nest materials of F.gagatoides,more than two fungi from Aphaenogaster sp.;while four fungi were isolated from the exoskeleton of F.gagatoides,and three fungi from Aphaenogaster sp.respectively.Among all fungi,Trichoderma sp.was the most prevalent fungus isolated from both the nest materials and worker exoskeleton of the aforementioned ant species.Further researches are required to determine the coevolutional relationship between those fungi and host ants and their influence to the ants＇ nesting activity and decomposition of woods.