White T C R
School of Applied Science, Riverina-Murray Institute of Higher Education, 2850, Wagga Wagga, N.S.W., Australia.
Oecologia. 1985 Oct;67(3):455-456. doi: 10.1007/BF00384955.
Mountain birch trees are said to survive as "green islands" around nests of red ants in Finnish Lapland because the ants kill larvae which would defoliate trees during outbreaks of the moth O. autumnata. An alternative hypothesis says that because the ants will concentrate soil nutrients (and possibly ameliorate soil moisture and temperature) in and around their nests, they provide a more favourable site for trees growing nearby. These trees are therefore less stressed and a poorer source of food for defoliators at times of outbreaks. Few if any young O. autumnata larvae survive on the trees which then survive in green islands around ant nests.
据说在芬兰拉普兰地区，山桦树能作为红蚁巢穴周围的“绿色岛屿”存活下来，因为蚂蚁会杀死蛾类O. autumnata爆发时会使树木落叶的幼虫。另一种假说认为，由于蚂蚁会在巢穴及其周围集中土壤养分（并可能改善土壤湿度和温度），它们为附近生长的树木提供了更有利的生长环境。因此，这些树木压力较小，在蛾类爆发时，对于食叶害虫来说是较差的食物来源。很少有（如果有的话）O. autumnata幼虫能在这些树木上存活，而这些树木随后会在蚁巢周围的绿色岛屿中存活下来。
