Lake sediment records of Arctic ecosystem responses to holocene climatic changes

加拿大北极地区目前正在经历迅速的环境变化，整个地区对气候变化特别敏感。为了了解气候变化的未来影响，并采取措施减轻这些影响，需要更好地了解北极生态系统。该研究计划使用古生态学技术来调查北极陆地和水生生态系统的长期发展。古生态学包括从湖泊或湿地收集沉积物岩心。这些沉积物已经积累了数千年，并提供了长期环境变化的档案。在我们的研究实验室里，我们研究保存在这些沉积物岩心中的微观生物遗骸。这些遗骸包括花粉粒或孢子等古植被的指示物，以及藻类、浮游动物和昆虫等水生生物。其中许多在沉积物岩心中保存完好，对它们的鉴定和研究提供了生态系统如何随时间变化的详细记录。结合独立产生的古气候信息，如从冰芯或海洋沉积物中获得的信息，可以量化北极陆地和水生生态系统对各种气候变化的反应。因此，越来越有可能建立生态系统功能的模型，并量化生物生产力或生物多样性在面对环境变化，包括气候变化或其他人类影响时为生态系统提供复原力方面的重要性。北极是一个广阔的区域，但很少有研究分析其陆地和水生生态系统的长期发展。对北极生态系统进行更多的长期研究很重要，因为这提供了一个机会，可以检验将扰动、多样性和复原力联系在一起的生态模型的普遍性，这些模型通常是为温带或热带生态系统生成的。

The Canadian Arctic is presently undergoing rapid environmental change and the region as a whole is particularly sensitive to climatic change. In order to understand the future impacts of climatic change, and to take measures to mitigate these impacts, a better understanding of Arctic ecosystems is needed. This research program uses paleoecological techniques to investigate the long-term development of both terrestrial and aquatic ecosystems in the Arctic. Paleoecology involves the collection of sediment cores from lakes or wetlands. These sediments have been accumulating for thousands of years and provide an archive of environmental change over long timescales. In our research laboratory, we study microscopic biological remains preserved in these sediment cores. These remains include indicators for paleo-vegetation such as pollen grains or spores, as well as aquatic organisms such as algae, zooplankton and insects. Many of these are well preserved in sediment cores and their identification and study provide detailed records of how ecosystems have changed over time. Taken in conjunction with independently generated paleoclimatic information such as that obtained from ice cores or ocean sediments, the responses of terrestrial and aquatic ecosystems in the Arctic to a variety of climatic changes can be quantified. Therefore, it will be increasingly possible to model the function of ecosystems and to quantify the importance of biological productivity or biodiversity in providing resilience to an ecosystem in the face of environmental changes including climatic changes or other human impacts. The Arctic is a vast region yet there are few studies that have analyzed the long-term development of its terrestrial and aquatic ecosystems. More studies of Arctic ecosystems on long time scales are important because they offer an opportunity to test the universality of ecological models linking disturbance, diversity and resilience, which are frequently generated for temperate or tropical ecosystems.