Long-term winter ecology and sea ice phenology in subarctic, high-use coastal ecosystems

全球变化对遍布加拿大的北温带沿海生态系统的结构和功能的破坏性影响可能是多方面的。例如，预计气温升高的后果将迅速影响到季节性海冰的动态，破坏其边缘（许多冷适应生物的重要栖息地）的稳定，并减少其覆盖范围、厚度和季节性持续时间。这些剧烈的变化可能引发级联效应，比如增强水柱分层的强度和持续时间，刺激富营养化。冰盖的减少也使海岸线更容易受到侵蚀，并可能增加冬季海上活动的强度。不断变化的环境条件和人类对北部沿海地区不断增加的利用相结合，可能对粮食网产生负面影响，并增加基础设施的脆弱性，危及生计。此外，在港口、工业和海事活动发生的地方，污染会加剧这些影响。如果要维持生态系统服务和生计，处理这些社会经济活动的可持续管理的政策必须依赖于对其对沿海环境健康的影响有扎实的科学认识。然而，北方港口缺乏用于解释当前环境状况和为基于科学的管理提供信息的基线和长期数据，这使得了解当前全球变化的影响成为一项重大挑战。因此，迫切需要获取这种生态系统类型的长期数据。在接下来的五年里，我的研究计划将集中在发展关于北温带高利用海岸的冬季生态和海冰季节性变化的知识。使用一种新颖的、多代理的方法来研究保存在沿海沉积物中的自然档案，我和我的团队将产生新的、长期的环境知识，广泛应用于加拿大和国际北部港口。圣劳伦斯湾（Gulf of St-Lawrence）的Sept-Iles地区拥有加拿大第二大深水港（按年吨位计算），是许多重工业的所在地，包括美洲最大的原铝冶炼厂。它是检验关于北部港口生态系统功能的假设，并为其定量理解和管理开发创新方法的理想模型。因此，我的研究计划最初将集中在这一地区，目标如下：1)重建过去冬季气候驱动因素的自然变率及其对北部沿海生态系统的影响；2)评估在全球快速变化的背景下，沿海食物网基础的冬季生态系统动态如何受到人类活动的影响。最终，我的团队的研究将有利于对加拿大和环北极地区高利用的沿海生态系统进行健全、科学的管理。

The disrupting effects of global change on the structure and function of north-temperate coastal ecosystems, which are widespread throughout Canada, are likely to be manifold. For example, it is expected that the consequences of warming temperatures will be felt rapidly on the dynamics of seasonal sea ice, destabilizing its margins, which are an important habitat for many cold-adapted organisms, and reducing its coverage, thickness, and seasonal duration. These drastic changes could trigger cascading effects like enhancing the strength and duration of stratification of the water column, stimulating eutrophication. Diminishing ice-cover also leaves coastlines more vulnerable to erosion and can boost the intensity of winter maritime activities. This combination of changing environmental conditions and increasing human use of northern coastal regions could negatively impact food webs and enhance infrastructure vulnerability, endangering livelihoods. Furthermore, where port, industrial, and maritime activities occur, pollution can exacerbate these effects. If ecosystem services and livelihoods are to be maintained, policies addressing the sustainable management of these socio-economic activities must rely on a solid scientific understanding of their impacts on the health of coastal environments. Yet baseline and long-term data from which to interpret current environmental conditions and inform science-based management are lacking for northern ports, making it a major challenge to understand the impacts of current global change. There is, therefore, a pressing need to acquire long-term data for this ecosystem type. During the next five years, my research program will focus on developing knowledge about the winter ecology and changing seasonality of sea ice in north-temperate, high-use coasts. Using a novel, multiproxy approach to study the natural archives preserved in coastal sediments, my team and I will generate new, long-term environmental knowledge of broad application to northern ports in Canada and internationally. The region of Sept-Iles, in the Gulf of St-Lawrence, has the second largest deep-water seaport in Canada by yearly tonnage and is home to many heavy industries, including the largest primary aluminum smelter in the Americas. It is an ideal model for testing hypotheses about the functioning of northern port ecosystems and developing innovative methods for their quantitative understanding and management. My research program will therefore initially focus on this region, with the following objectives : 1) To reconstruct past natural variability of winter climatic drivers and their impact on northern coastal ecosystems, and 2) To assess how recent winter-time ecosystem dynamics at the base of the coastal food web are affected by human activities in the context of rapid global change. Ultimately, my team's research will benefit sound, science-based management of high-use coastal ecosystems in Canada and around the circumpolar North.