Long-term responses of aquatic ecosystems to environmental change

我的NSERC研究项目将专注于极地水生生态系统及其对环境变化的长期反应。我的研究团队将把重点放在三个中心主题上：(1)了解埃尔斯米尔岛北部冰架和海冰的历史是至关重要的，因为北部冰架不仅是北极气候变暖的宝贵哨兵，而且由于它们反映了海冰条件，它们还会对航运产生影响，而且它们的破裂可能会产生威胁船舶安全的冰岛。我们将从峡湾沉积岩心重建埃尔斯米尔岛北部冰架的全新世历史。(2)在努纳维克的Tursujuq国家公园建立长期气候变化和哈德逊湾海冰影响的记录：哈德逊湾地区是20世纪北极受气候变化影响最小的地区之一；在过去20年中，它一直是变暖最快的地区之一，这主要是由于最近海冰的减少。这些变化对当地居民重要的陆地生态系统有重要影响，包括湖冰、永久冻土条件和植物物候。需要对哈德逊湾东部的长期气候动态进行研究，以了解区域气候变化及其对陆地生态系统的影响。(3)在南极半岛，我们将讨论这样一种假设，即与考察站有关的人类活动产生和/或转移了沉积在湖泊集水区的污染物，造成了流域侵蚀和营养浓度的变化，并改变了湖泊生物群。我们对南极洲受影响最严重的地区之一菲尔德斯半岛的湖泊进行了古湖沼学研究，研究重建了这些变化。我们将检查多种生物和地球化学指标，以确定人类到来之前的条件，并确定当地人为活动造成的变化程度。由于北极和南极生态系统之间的相似之处，了解人类对脆弱的南极生态系统的影响也将有助于指导北方地区的未来发展。 这些目标将通过分析湖泊和峡湾的沉积记录，使用现代古生态技术来推断过去的环境条件来实现。研究中使用的替代指标将包括硅藻、光合色素、有机质和地球化学标志物。我的研究将为影响世界上一些变化最迅速的区域的水生生态系统的关键问题提供见解，这些研究产生的理解将因此使北方社区能够预测和适应当地水生生态系统作为关键自然资源的未来变化。我的研究将提高公众意识，向政策制定者提供信息，并帮助在用水问题上做出合理的决策。

My NSERC research program will focus on polar aquatic ecosystems and their long-term responses to environmental change. My research team will place emphasis on three central themes: (1) Understanding the history of ice shelves and sea ice along northern Ellesmere Island is critical because not only are northern ice shelves valuable sentinels of Arctic climate warming, but they also have implications for shipping given that they reflect sea ice conditions, and their fracturing may spawn ice islands that threaten ship safety. We will reconstruct the Holocene history of northern Ellesmere Island ice shelves from fiord sediment cores. (2) Developing records of long-term climate change and the effects of Hudson Bay sea ice in Tursujuq National Park, Nunavik: The Hudson Bay region was among the parts of the Arctic least affected by climate change during the 20th Century; over the past two decades it has been among the most rapidly warming regions largely due to recent sea ice declines. Such changes have important effects on terrestrial ecosystems important to local residents, including lake ice, permafrost conditions and plant phenology. Studies of long-term climate dynamics in eastern Hudson Bay are needed to understand regional climate change and its consequences for terrestrial ecosystems. (3) In the Antarctic Peninsula we will address the hypothesis that human activities related to research stations have produced and/or mobilized contaminants that have been deposited in lake catchments, caused changes in catchment erosion and nutrient concentrations, and altered lake biota. We study reconstruct these changes using paleolimnological studies of lakes on Fildes Peninsula, one of the most impacted regions in Antarctica. We will examine multiple biological and geochemical indicators to establish conditions prior to the arrival of humans and determine the degree of change due to local anthropogenic activities. The understanding of human effects on fragile Antarctic ecosystems will help also help guide future development in northern regions due to the similarities between Arctic and Antarctic ecosystems. These objectives will be accomplished through analysis of the sedimentary records of lakes and fiords, using modern paleoecological techniques to infer past environmental conditions. Proxy indicators applied in the research will include diatoms, photosynthetic pigments, organic matter and geochemical markers. My research will provide insights into critical issues affecting aquatic ecosystems in some of the world's most rapidly changing regions and the understanding generated by these studies will thus enable northern communities to predict and adapt to future changes of the local aquatic ecosystems that are crucial natural resources. My research will increase public awareness, inform policymakers and assist sound decision making in water use issues.