Ecological interactions in high places: patterns, processes and consequences

确定物种相互作用、资源可用性和非生物因素（如天气/气候）何时、何地以及如何影响不同生态系统中的人口和群落动态，仍然是生态学的重大挑战之一。持续的实地观察和实验对于检验和推进生态学理论至关重要；改进对人口、社区和生态系统如何对累积效应或随机事件（干扰）作出反应的预测；并为保护生物多样性、恢复退化的栖息地和管理全球和地方气候变化的意外后果制定可行的战略。在过去的25年里，我的研究项目集中在揭示山地和高纬度陆地环境中植物-草食动物-气候相互作用的一些关键方面。在这些生态系统中，预计变暖的影响将被放大，这些变化的影响将导致与当前状态不同的新情况。向这种“新常态”的过渡似乎是由冰雪减少所驱动的，并将产生深远的影响。我在SFU的研究小组和扩展的合作者网络都采用了跨学科的方法来研究植物-草食动物-气候相互作用的动态。我的研究项目的主要重点研究区域位于育空地区西南部的山区，该地区持续经历快速变暖。这项研究是与不同群体的学生、大学和政府科学家以及北方合作伙伴合作进行的。这些生态系统对我的研究有很多好处，因为：大多数生物活动发生在短暂的夏季；许多物种可以在生态相关的尺度上进行研究和操作；生态学理论可以沿着陡峭的生态梯度进行检验；全球变化模型（和数据）表明，一些最大的响应将发生在更高的海拔。在本提案中，我确定了新的研究活动，重点关注以下事项：(1)确定气候、资源可用性、竞争和捕食风险的变化如何影响育空地区物种范围边缘的鼠兔的行为、人口和分布；(2)确定影响北极草食动物多样性和保护热点的过程；(3)确定营养相互作用强度沿海拔梯度的变化规律；4)对西南育空地区的气象、湖泊和生态变量进行长期测量，以确定气候对北部山区环境生态变化速率和轨迹的影响。在这项新的NSERC发现基金的五年里，我的研究项目将为2名pdf， 2名博士和3名硕士学生，至少8-10名本科生，以及来自我们合作的当地社区（包括育空第一民族社区）的青年提供培训。

Determining when, where and how species interactions, resource availability, and abiotic factors (e.g. weather/climate) influence population and community dynamics in different ecosystems remains one of the great challenges in ecology. Sustained field observations and experiments are essential for testing and advancing ecological theory; for improving predictions about how populations, communities and ecosystems respond to cumulative effects or stochastic events (disturbance); and for developing viable strategies for conserving biodiversity, restoring degraded habitats and managing the unexpected consequences of global and local climate change. Over the past 25-years my research program has focused on unraveling some key aspects of plant-herbivore-climate interactions in mountain and high latitude terrestrial environments. In these ecosystems, the effects of warming are expected to be amplified and the impacts of these changes will lead to new conditions that will not resemble current states. The transition to this "new normal" appears to be driven by reduced ice and snow, and will have far-reaching consequences. Both my research group at SFU and extended networks of collaborators have adopted an interdisciplinary approach to studying the dynamics of plant-herbivore-climate interactions. The primary focal study areas for my research program are located in the mountains of the southwest Yukon, a region that continues to experience rapid warming. This research has been conducted in collaboration with a diverse group of students, university and government scientists, and northern partners. These ecosystems have many advantages for my research because: most biological activity occurs during a short summer; many species can be studied and manipulated at ecologically relevant scales; ecological theory can be tested along steep ecological gradients; and global change models (and data) indicate that some of the largest responses will occur at higher elevation. In this proposal, I identify new research activities focused on the following priorities: (1) determine how variation in the effects of climate, resource availability, competition and predation risk affect the behaviour, demography and distribution of collared pikas at the edge of the species range in Yukon; (2) identify processes influencing hotspots of herbivore diversity and conservation in the Arctic; (3) determine how the strength of trophic interactions change along elevational gradients; and 4) sustain long-term measurements of meteorological, limnological and ecological variables in southwest Yukon, to determine the influence of climate on rates and trajectory of ecological change in northern mountains environments. Over the five years of this new NSERC Discovery Grant my research program will provide training for 2 PDFs, 2 PhD and 3 MSc students, at least 8-10 undergraduates, as well as youth from the local communities (including Yukon First Nation communities) that we work with.