Testing resource-based models of patchiness in four Neotropical litter ant assemblages
Testing resource-based models of patchiness in four Neotropical litter ant assemblages
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DOI：
10.2307/3546338
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发表时间：
1996-09-01
期刊：
影响因子：
3.4
通讯作者：
Kaspari, M
中科院分区：
文献类型：
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作者：
Kaspari, M
在四个新热带森林中，我研究了资源可用性如何影响垃圾蚂蚁的斑块状，垃圾蚂蚁的群体大约有 100 只工蚁，生活在空心的树枝中。在区域范围内，与物种能源理论相反，哥斯达黎加和巴拿马森林具有相似的物种丰富度，尽管前者的生产力更高。在 m(2) 尺度上，巢密度变化了 10 倍，通常超过 10 个巢/地块。我测试了四个将这种不完整与资源限制和枯竭联系起来的预测。首先，随着对垫料数量和质量的估计，巢穴密度略有增加。其次，在两个巴拿马组合中，四个月后，巢穴添加实验使蜂群密度增加了一倍。第三，大多数常见物种的群体在较小时的生长速度似乎与较大时一样快。第四，菌落之间没有自我稀疏的迹象：具有大菌落的地块在去除凋落物的影响后并没有减少菌落。综合起来，这些结果表明，垃圾中的资源，尤其是巢穴，可能会限制局部斑块，但几乎没有证据表明食物枯竭。不稳定的垃圾环境可能会阻碍热带垃圾蚁群的规模或数量的增长，从而使其环境饱和。
In four Neotropical forests I studied how resource availability affected patchiness in litter ants, colonies of about 100 workers living in hollow twigs. At the regional scale, and contrary to Species Energy Theory, Costa Rica and Panama forests had similar species richness, despite the former being more productive. At the m(2) scale, nest densities varied 10-fold, often exceeding 10 nests/plot. I tested four predictions linking this patchiness to resource limitation and depletion. First, nest densities increased weakly with estimates of litter quantity and quality. Second, nest addition experiments doubled colony densities after four months in the two Panama assemblages. Third, colonies of most common species appeared to grow as fast when they were small as when they were large. Fourth, there was no suggestion of self-thinning among colonies: plots with large colonies did not have fewer colonies after removing the effects of litter. Combined, these results suggest that resources in the litter, most notably nest sites, may limit local patchiness, but that there is little evidence for food depletion. The unstable litter environment may preclude tropical litter ant colonies from growing large or populous enough to saturate their environment.