Ecological Effects of Global Change: Tree-Insect Interactions

小行星9306981 大气中二氧化碳浓度的增加和随之而来的气候变化预计将对森林生态系统产生重大影响。 你对这些变化将如何影响生态相互作用的理解，特别是树木和食树昆虫之间的相互作用，充其量只是初步的。 CO2浓度升高可以显著改变落叶树的叶片化学，包括氮的减少和碳水化合物和碳基次生代谢物的增加。 这些变化改变了食叶鳞翅目昆虫的表现。 CO2与其他环境因素（养分有效性，落叶）相互作用，并可能与植物基因型影响叶片化学和昆虫的表现。 本研究探讨了CO2浓度升高、资源可利用性和植物基因型对树木-植食性昆虫-寄生性天敌相互作用的直接和交互影响。 实验系统包括颤抖的白杨，红橡树和糖枫（表现出一系列的固有增长率和耐荫性），两个食叶昆虫（舞毒蛾和森林帐篷毛虫）和舞毒蛾幼虫寄生（Cotesia melanoscelus）。 碳-养分平衡理论为三个主要目标相关假说的发展提供了一个框架。 这些目标是确定CO2浓度升高和1）干旱胁迫，2）光照可用性，3）白杨基因型对树木化学成分的影响，以及对昆虫食草动物和寄生蜂C的影响。黑痣 许多研究人员和研究机构已经确定了植物和食草动物相互作用的研究，作为理解全球变化的生态后果的关键。 这项研究将有助于满足这一需求。 这项研究的特点包括强调CO2和环境系统的相互作用，以及使用北美落叶林在生态和经济上重要组成部分的树木和昆虫物种。

9306981 Lindroth Increasing concentrations of atmospheric CO2 and attendant climate change are expected to have significant impacts on forest ecosystems. You understanding of how these changes will affect ecological interactions, especially those between trees and tree-feeding insects, is at best rudimentary. Elevated CO2 can markedly alter the foliar chemistry of deciduous trees, including reductions in nitrogen and increases in carbohydrates and carbon-based secondary metabolites. These changes alter the performance of leaf-feeding Lepidoptera. CO2 interacts with other environmental factories (nutrient availability, defoliation) and possibly with plant genotype affect leaf chemistry and insect performance. This research investigates the direct and interactive effects of elevated CO2, resource availability and plant genotype on tree-herbivore-parasitoid interacations. The experimental system includes quaking aspen, red oak and sugar maple (which exhibit a range of inherent growth rates and shade tolorances), two leaf-feeding insects (gypsy moth and forest tent caterpillar) and a gypsy moth larval parasitioid (Cotesia melanoscelus). Carbon-nutrient balance theory provides a framework for development of three major goal associate hypotheses. These goals are to determine effects of elevated CO2 and 1) drought stress, 2) light availability, and 3) aspen genotype on tree chemical composition, and consequences for performance of insect herbivores and the parasitoid C. melanoscelus. %%% Numerous researchers and research agencies have identified studies on interactions of plants and herbivores as pivotal in understanding the ecological consequences of global change. This research will help address that need. Special features of this research include an emphasis on interactive effects of CO2 and environmental system, and use of tree and insect species that are ecologically and economically important components of North American deciduous forests.