Diversity and resilience of plant communities in isolated ecosystems

在世界上许多地方，生态系统遭到破坏和破碎的比例如此之高，以至于剩下的植物群落被限制在一个人为生境的基质内。该基质的组成、结构和景观动态对剩余生态系统的多样性和动态具有重要影响。***我的研究计划的长期目标是增加我们对影响受人类栖息地约束的植物群落恢复力的过程的理解。最终，这项研究将为减轻环境变化对生态系统的直接和间接影响的战略提供信息。我的短期目标是1)评估树木入侵对湿地组成、多样性和恢复力的影响；2)研究城市化与生物同质化的关系。为实现这前两个目标而开展的项目也将使确定哪些过程和组成部分负责社区组装和beta多样性变化成为可能。***农业景观中孤立的沼泽以及城市森林和空置的草本地块将作为研究模型。为了确定多样性和组成的变化，我的团队将主要使用重新采样方法（重新访问30-40年前采样的地块）和时空替代方法。由于植物对景观变化的反应往往具有时间滞后，因此这种历史方法可以在变化的驱动因素和环境反应之间建立强有力的联系。我的项目提供了一个独特的机会来提高我们对控制生态系统动态和组成的生态过程和机制的认识。这些知识对于最终能够促进生态系统在面对日益增长的人为压力时的恢复能力，以及改善生态系统，特别是湿地和城市生态系统的保护和可持续管理计划至关重要。***由于我的项目，许多HQP将有机会发展在统计学，植物生物学和保护方面非常有价值的技能。如果他们愿意，理学硕士学生都将获得攻读社区生态学博士学位所需的技能和知识，或者为他们提供与高级生物学相关的就业机会。博士生将掌握社区集会过程的先进知识，并将为研究事业做好准备。

In many parts of the world, the destruction and fragmentation of ecosystems have reached such a high proportion that remaining plant communities are constrained within a matrix of humanized habitats. The composition, structure and landscape dynamics of this matrix exert a strong influence on the diversity and dynamics of remaining ecosystems. ***The long-term objective of my research program is to increase our understanding of the processes that influence the resilience of plant communities constrained within a matrix of humanized habitats. Ultimately, this research will inform strategies for mitigating the direct and indirect impacts of environmental changes on ecosystems. ***My short-term goals are to 1) evaluate the effect of tree encroachment on wetland composition, diversity and resilience and 2) investigate the relationship between urbanization and biotic homogenization. The projects carried out to achieve these first two objectives will also make it possible to 3) identify which processes and components are responsible for community assembly and beta diversity changes.***Bogs isolated in agricultural landscapes as well as urban forests and vacant herbaceous lots will serve as study models. To identify changes in diversity and composition, my team will primarily use a resampling approach (revisiting plots sampled 30-40 years ago) and a space-for-time substitution methodology. Such a historical approach enables robust links between the drivers of change and environmental response to be made, as plants often have a time-lagged response to landscape modifications.***My program offers a unique opportunity to improve our knowledge of the ecological processes and mechanisms that govern ecosystem dynamics and composition. This knowledge is essential to eventually be able to foster ecosystem resilience in face of growing human-induced pressures and to improve programs for the conservation and sustainable management of ecosystems, especially those specific to wetlands and urban ecosystems. ***Thanks to my program, many HQP will have the opportunity to develop highly valuable skills in statistics, plant biology and conservation. MSc students will all acquire the skills and knowledge necessary to pursue doctoral studies in community ecology if they wish or equip them for advanced biology-related employment. PhD students will come to possess advanced knowledge on the processes responsible for community assembly and will be well positioned for a research career.