Moths, Ants and Pitcher Plants in Bogs at Harvard Forest and Belchertown MA since 2007

Ecologists have long recognized that coexistence of interacting species depends on a diversity of separate, but linked habitats. Most models of species coexistence treat these habitat "patches" as unchanging elements of the landscape, but in reality, they are constantly changing in size and shape. The structure and dynamics of the food webs that inhabit them both control and depend on these changes. In this five-year (2006-2011) collaborative project, we are using a combination of extensive field surveys and intensive field experiments to understand how species interactions change the spatial distribution of dynamic habitat patches across the landscape, and to determine how food webs are structured within and among these patches. The experimental system for this five-year research project is the Sarracenia "microecosystem": the northern pitcher-plant Sarracenia purpurea; the unique food web of bacteria, protozoa, rotifers, mites, and fly larvae that live within its rainwater-filled leaves; three species of bog-inhabiting ants that are the primary prey for this carnivorous plant; and larvae of the pitcher-plant moth, Exyra fax, which cut and drain pitchers and remove food web habitat. Results from surveys of bogs in all six New England state and field experiments conducted at bogs at Harvard Forest and Belchertown, Massachusetts will be used to parameterize a simulation model to predict changes in spatial structure of ant, moth, and plant populations, and the structure and composition of the aquatic food web associated with the plant. This work is funded by the U.S. National Science Foundation, through collaborative awards 0541680 and 0541936.

生态学家早已认识到，相互作用的物种的共存依赖于多种既相互独立又彼此关联的生境。绝大多数物种共存模型均将这些生境斑块视为景观中恒定不变的组成部分，但现实中它们的面积与形态始终处于动态变化之中。栖息于其中的食物网的结构与动态，既受这些变化调控，同时也反过来影响这些变化。在这项为期五年（2006-2011年）的合作研究项目中，我们结合大范围野外调查与精细化野外实验，旨在阐明物种间相互作用如何改变景观内动态生境斑块的空间分布，并解析食物网在这些斑块内部及斑块之间的构建模式。本五年研究项目的实验系统为瓶子草（Sarracenia）微生态系统：包括北方瓶子草（Sarracenia purpurea）；栖息于其积水捕虫笼内的独特食物网，涵盖细菌、原生动物（protozoa）、轮虫（rotifers）、螨类（mites）与蝇幼虫；三种栖息于泥炭沼泽的蚂蚁，为该食肉植物的主要猎物；以及瓶子草蛾（Exyra fax）的幼虫，它们会切割并排空捕虫笼，进而移除食物网生境。我们将基于对新英格兰全部六个州的泥炭沼泽的调查结果，以及在马萨诸塞州哈佛大学森林保护区与贝尔彻敦的泥炭沼泽开展的野外实验数据，对模拟模型进行参数化，以此预测蚂蚁、蛾类与植物种群的空间结构变化，以及该植物关联的水生食物网的结构与组成。本研究由美国国家科学基金会（U.S. National Science Foundation）通过合作资助编号0541680与0541936提供资金支持。