Center for Population Biology, University of California, Davis, CA 95616-8755, USA.
Oecologia. 2011 Jun;166(2):411-20. doi: 10.1007/s00442-010-1851-6. Epub 2010 Nov 27.
Protective ant-plant mutualisms-where plants provide food or shelter to ants and ants protect the plants from herbivores-are a common feature in many ecological communities, but few studies have examined the effect of disturbance on these interactions. Disturbance may affect the relationship between plants and their associated ant mutualists by increasing the plants' susceptibility to herbivores, changing the amount of reward provided for the ants, and altering the abundance of ants and other predators. Pruning was used to simulate the damage to buttonwood mangrove (Conocarpus erectus) caused by hurricanes. Pruned plants grew faster than unpruned plants, produced lower levels of physical anti-herbivore defenses (trichomes, toughness), and higher levels of chemical defenses (tannins) and extrafloral nectaries. Thus, simulated hurricane damage increased plant growth and the amount of reward provided to ant mutualists, but did not have consistent effects on other anti-herbivore defenses. Both herbivores and ants increased in abundance on pruned plants, indicating that the effects of simulated hurricane damage on plant traits were propagated to higher trophic levels. Ant-exclusion led to higher leaf damage on both pruned and upruned plants. The effect of ant-exclusion did not differ between pruned and unpruned plants, despite the fact that pruned plants had higher ant and herbivore densities, produced more extrafloral nectaries, and had fewer physical defenses. Another common predator, clubionid spiders, increased in abundance on pruned plants from which ants had been excluded. I suggest that compensatory predation by these spiders diminished the effect of ant-exclusion on pruned plants.
植物为蚂蚁提供食物或庇护所，而蚂蚁则保护植物免受食草动物的侵害，这种保护性的动植物共生关系在许多生态群落中很常见，但很少有研究探讨干扰对这些相互作用的影响。干扰可能通过增加植物对食草动物的易感性、改变蚂蚁的报酬量以及改变蚂蚁和其他捕食者的丰度来影响植物与其共生蚂蚁之间的关系。修枝被用来模拟飓风对海桑（Conocarpus erectus）造成的破坏。修剪过的植物比未修剪的植物生长得更快，产生的物理抗食草动物防御（刚毛、韧性）水平更低，而化学防御（单宁）和额外花蜜腺的水平更高。因此，模拟飓风破坏增加了植物的生长和为蚂蚁共生者提供的报酬量，但对其他抗食草动物防御没有一致的影响。食草动物和蚂蚁的数量都在修剪过的植物上增加，这表明模拟飓风破坏对植物特征的影响传播到了更高的营养级。在修剪过和未修剪过的植物上，蚂蚁排除都会导致叶片损伤增加。尽管修剪过的植物蚂蚁和食草动物密度更高，产生了更多的额外花蜜腺，而且物理防御更少，但蚂蚁排除的效果在修剪过和未修剪过的植物之间没有差异。另一种常见的捕食者，卷叶蛛，在被蚂蚁排除的修剪过的植物上数量增加。我认为这些蜘蛛的补偿性捕食减少了蚂蚁排除对修剪过的植物的影响。
