LTREB: The population dynamics of forest understory invasion: mechanistic experiments with generalist herbivores, natives, and invaders

通过长期排除鹿（本土植物食用者）和大蒜芥（化感森林入侵者）的实验，本研究者已经证明了1)鹿的过多会促进大蒜芥入侵森林，2)大蒜芥和鹿的存在会导致本土多年生草本植物种群的减少，3)鹿和大蒜芥对森林土壤特征产生负面影响。本研究将对7年的重点原生草本林下物种数据进行扩展和扩充，分析鹿和蒜芥菜对重点物种种群的影响。利用积分投影模型（Integral Projection Models）这一强大的人口统计学新方法，预测不同鹿群和外来入侵情景下焦点物种的长期生存或灭绝。这项研究将为鹿和大蒜芥这对强大的破坏性二人组对森林原生植物种群和整个森林植物群落的可持续性的直接、间接和协同相互作用提供新的见解。入侵物种和过多的鹿威胁着本地生态系统的功能完整性，每年造成数十亿美元的经济损失。本研究的结果将通过扩展我们对多物种营养森林相互作用（鹿、入侵者和本地物种）的基本认识，为鹿和蒜芥菜对森林生态系统管理者的影响提供所需的信息。这些研究人员将通过公开讲座、基于我们的发现开发高中教师研讨会、为非营利委员会和社区组织提供服务，以及通过继续开发虚拟Trillium Trail (VTT)（一个计算机游戏平台，根据我们的实地数据通过我们的实地站点提供虚拟实地考察），继续开展外联工作和社区参与。VTT作为一种学习工具的有效性已被中学生严格评估。研究培训将包括本科生和研究生以及一名博士后。

Using long-term experimental plots that exclude deer (native plant consumer) and garlic mustard (allelopathic forest invader), this investigator previously demonstrated that 1) over-abundant deer facilitate forest invasion by garlic mustard, 2) the presence of both garlic mustard and deer cause native perennial herb populations to decline, and 3) deer and garlic mustard negatively affect forest soil characteristics. The proposed research will extend and expand the seven-year dataset on key focal native herbaceous forest understory species to analyze the effects of deer and garlic mustard on population demography of the focal species. Integral Projection Models, a powerful new demographic method, will be employed to predict the long-term persistence or extinction of the focal species under different deer and invader scenarios generated by these experiments. This research will return novel insights into the direct, indirect and synergistic interactions of the powerfully disruptive duo, deer and garlic mustard, on the sustainability of forest native plant populations and the forest plant community as a whole. Invasive species and overabundant deer threaten the functional integrity of native ecosystems and cause billions of dollars in economic losses annually. Results of this research will yield needed information on the effects of deer and garlic mustard to forest ecosystem managers by expanding our basic understanding of multi-species trophic forest interactions (deer, invader and natives). These researchers will continue outreach efforts and community engagement via public lectures, the development of a high school teacher workshop based on our findings, service on a non-profit board and community organizations, and through continued development of Virtual Trillium Trail (VTT), a computer gaming platform that provides a virtual field trip through our field site based on our field data. The effectiveness of VTT as a learning tool has been rigorously assessed with middle school students. Research training will include undergraduate and graduate students and a post-doctoral fellow.