Relocation and Concentration in the 2004 Emergence of Periodical Cicadas

周期蝉的出现是一种壮观的事件，可能会对森林生态产生重要影响。这个项目是对一般假设的调查，这一假设认为，人类对森林环境的改变通过使蝉集中在特定环境中来增加蝉的出现的影响。周期蝉大部分时间生活在地下，但成虫每隔13或17年出现繁殖一次，它们在短暂羽化期的空间行为解释了蝉种群的迁移和集中。蝉的大量生物量产生了从地下到地上的主要营养通量。新出现的蝉也会对树木和灌木造成实质性的损害，因为它们在树枝上产卵，从而结束了成熟若虫大量取食树根的时期，并开启了下一代年轻若虫较轻取食的时期。这些影响可能会通过有利于某些种类的乔木和灌木来改变生态动态，但影响将取决于蝉的空间集中程度。这种浓度很可能会因为人类对森林的改造而改变，因为蝉会选择森林边缘的区域和最近的干扰来储存产卵的下一代。最大的一窝周期蝉将在2004年春季出现，分析将基于空间样本，这些样本将足以分析蝉在羽化前后的种群位置。这些样本将被用来检验关于蝉种群净迁移和集中的具体假设，使用空间统计分析方法。该项目将揭示人类活动与自然过程相结合的具体特征，特别是蝉的空间行为，以改变生态动态和改变森林环境。

Emergences of periodical cicadas are spectacular events and may exert important effects on forest ecology. This project is an investigation of the general hypothesis that human modifications of forest environments increase the effects of cicada emergences by causing cicadas to concentrate in particular environments. Periodical cicadas spend most of their lives underground but adults emerge to reproduce, at 13 or 17-year intervals, and their spatial behavior during the brief emergence period accounts for the relocation and concentration of cicada populations. The large biomass of cicadas produces a major flux of nutrients from below to above ground. Emerging cicadas also inflict substantial damage on trees and shrubs as they deposit eggs in twigs and the emergence ends a period of heavy feeding on tree roots by maturing nymphs and initiates a period of lighter feeding by younger nymphs of the next generation. These effects may alter ecological dynamics by favoring some species of trees and shrubs but the effects will depend on the spatial concentration of cicadas. That concentration is likely to be altered by human modification of the forest, since cicadas select areas of forest edge and recent disturbance to deposit the eggs that produce the next generation. The largest brood of periodical cicadas will emerge in Spring, 2004 and the analysis will be based on spatial samples that will be sufficient to analyze the location of the cicada population before and after the emergence. The samples will be used to test specific hypotheses about the net relocation and concentration of the cicada population using methods for spatial statistical analysis. The project will reveal specific features of the ways that human activity works in conjunction with a natural process, specifically the spatial behavior of cicadas, to alter ecological dynamics and modify a forest environment.