Climate change and vulnerability of the sub-arctic ecosystem near Hudson Bay

气候变化对北极生物多样性的保护提出了重大挑战。全球变暖会破坏营养关系，改变复杂的物种相互作用，包括栖息地、捕食者-猎物关系、竞争和物种分布的变化。为了了解如何保护北极生物多样性，需要对影响北部生态系统变化的机制进行量化。种群可能对范围边缘的环境驱动因素最敏感，我的研究将通过对物种-环境分布的前沿和后缘的研究，提高对北方生态系统变化机制的理解。为了满足这一需求，我的研究项目在哈德逊湾低地开展，这是一个全球重要的湿地，重叠了连续永久冻土层的南部范围和一些适应北极的野生动物。我们将结合短期研究和长期数据集来检验关于物种-环境相互作用介导的生态系统变化驱动因素的假设。三个重点领域将支持我们的研究目标：1)测试气候变化是否通过对永久冻土的相互作用影响野生动物栖息地的可用性和质量；2)考察气候、捕食和生境条件对亚北极生态系统中中等营养水平的影响，特别是滨鸟和水禽的巢地选择和繁殖生态；3)验证气候变暖和涉及竞争的领先-后缘动态是否会影响北极狐在亚北极生态系统中的脆弱性和功能角色。目标-1将采用地面测量和遥感技术来描述季节性天气模式、永久冻土动态（如活动层深度）、湿地水文和植被结构之间相互作用造成的生境变化。目标-2将重点研究水鸟（加拿大鹅和滨鸟）的巢址选择和繁殖成功与捕食、气候和栖息地条件的相互作用（根据目标-1）。目标-3将侧重于北极狐作为一种关键指示物种的作用，它既具有影响力，又受生态系统中其他营养水平的影响。我的研究项目将全面评估环境变化如何影响北极物种分布的边缘，帮助阐明一般机制，预测未来趋势，并为资源管理决策提供信息。我的研究计划包括对15名HQP（5名研究生和10名本科生暑期学生）的培训，并将使学生获得实地研究技能，先进技术（如遥感）和北极生态学的理论知识。HQP将参加一个由学术界、土著社区和政府组成的团队，将科学应用于可持续资源管理。

Climate change poses a significant conservation challenge to arctic biodiversity. Global warming can disrupt trophic relationships and alter complex species interactions, including changes to habitat, predator-prey relationships, competition, and species distributions. Quantifying the mechanisms affecting change in northern ecosystems is needed to understand how arctic biodiversity may be conserved. Populations may be most sensitive to environmental drivers at the edge of range and my research will improve understanding of the mechanisms of change in northern ecosystems through studies at the leading and trailing edges of species-environmental distributions. To address this need, my research program operates in the Hudson Bay Lowlands, a globally significant wetland overlapping the southern range limit of continuous permafrost and several arctic adapted wildlife. We will use a combination of short-term studies and long-term datasets to test hypotheses regarding drivers of ecosystem change mediated by species-environment interactions. Three focal areas will support our research goals: 1) to test whether climate change affects the availability and quality of wildlife habitat through interacting effects on permafrost; 2) to test the relative importance of climate, predation, and habitat condition to affect intermediate trophic levels in the sub-arctic system, specifically nest-site selection and breeding ecology of shorebirds and waterfowl; and 3) test hypotheses as to whether climate warming and leading-trailing edge dynamics involving competition affect the vulnerability and functional role of arctic fox in the sub-arctic ecosystem. Objective-1 will employ ground measurements and remote sensing technology to characterize changes in habitat caused by interactions among seasonal weather patterns, permafrost dynamics (e.g. active layer depth), wetland hydrology and vegetation structure. Objective-2 will focus on studies of water bird (Canada geese and shorebirds) nest site selection and breeding success in relation to predation, climate and interactions with habitat condition (informed by Objective-1). Objective-3 will focus on the role of the arctic fox as a key indicator species that is both influential and affected by other trophic levels in the ecosystem. My research program will provide a comprehensive assessment of how environmental change impacts arctic species at the edge of their distributions, helping to clarify general mechanisms, anticipate future trends, and inform resource management decisions. My research program includes training for 15 HQP (5 graduate students and 10 undergraduate summer students) and will allow students to gain skills in field studies, advanced technologies (e.g. remote sensing), and theoretical knowledge in arctic ecology. HQP will participate in a team setting involving academia, indigenous communities, and government involving application of science to sustainable resource management.