Plant colonisation in the hight Arctic, a seed for change

迅速变化的北极环境将改变实际的生态平衡（例如植物-食草动物关系），并促进植被转移。 在稀疏的高北极植被，生殖输出预计将改善和增加植物建立。然而，物种对变化的反应也将取决于所涉及的生物相互作用，可以促进或抑制植物生长和建立。 我最近的工作表明，促进增加植物建立垫植物（主要是草本植物）和生物土壤结皮（草本植物和灌木）在高北极。然而，变暖可能导致干旱和竞争限制幼苗建立。占主导地位的灌木物种在开阔地的殖民地是罕见的，但它是必不可少的一个实质性的“北方绿化”发生。 自1989年以来，我一直活跃在北极地区，我的长期目标是为植被动态的生态理论做出贡献。我的短期目标是启动第一个大规模的种子添加实验与生物土壤结壳去除测试：1）种子短缺和安全的网站限制的相对重要性;和2）在两个对比的护士，保护系统的高北极植物殖民竞争和促进之间的平衡。 这些实地实验将包括变暖和浇水处理，并解决问题，如：是什么阻止占主导地位的维管物种（如灌木）的建立？ 全球变化会促进还是减少他们的招募？我的工作发生在池塘入口（NU）附近的拜洛特岛研究营地（73°N，80°W）。 我参加这个研究小组大大降低了后勤成本，改善了科学互动。 我计划培养1博士，2硕士和至少4个理科学生与这个项目。 我们将向当地社区提交关于我们研究活动的年度报告，并在第5年协调冬季访问，以便更全面地交流我们的成果。首先要解决这个系统中的理论和实践问题，这项工作将是加拿大最北端的生物群落的理解，保护和未来管理的重大贡献。

The rapidly changing arctic environment will alter the actual ecological balance (e.g. plant-herbivore relationships) and promote vegetation shifts.  In sparse high arctic vegetation, reproductive output is predicted to improve and increased plant establishment is expected. However, species response to change will also depend on the biotic interactions involved that can promote or prohibit plant growth and establishment.  My recent work revealed that facilitation increases plant establishment in cushion plants (mostly herbs) and biological soil crusts (herbs and shrubs) in the High Arctic. However, warming may lead to increased drought and competition limiting seedling establishment. Colonisation of open grounds by dominant shrub species is rare, yet it is essential for a substantial 'greening of the North' to take place.        Active in the Arctic since 1989, my long-term objective is to contribute to the ecological theory of vegetation dynamics. My short term objectives are to initiate the first large scale seed addition experiments with biological soil crust removal to test: 1) the relative importance of seed shortage and safe site limitation; and 2) the balance between competition and facilitation in plant colonisation in two contrasting nurse-protégé systems of the High Arctic.  These field experiments will include warming and watering treatments and address questions such as:  What prevent dominant vascular species (e.g. shrubs) establishment?  Will global change promote or decrease their recruitment? My work takes place near Pond Inlet (NU) around the Bylot Island research camp (73°N, 80°W).  My participation to this research group significantly reduces logistical costs and improves scientific interactions.  I plan to train 1 PhD, 2 MSc and a minimum of 4 BSc students with this project.  We will present annual reports on our research activities to the local communities and coordinate a winter visit in Yr 5 to allow more thorough exchanges on our results. First to address such theoretical and practical questions in this system, this work will be a significant contribution to the understanding, conservation and future management of Canada's northernmost biome.