Evolution of North American Ecosystems over the past 20,000 years

该研究项目使用古环境方法来了解气候变化和气候变化对陆地和淡水生态系统的影响。该研究项目的目的是研究气候变率的尺度和机制，量化陆地和淡水生态系统的相互作用以及对长期气候变率的响应。从冰河时代结束时人类首次到达大陆，到广泛农业的引入，欧洲人的到来和快速工业化，人类影响在连续统一体中的作用是研究计划的一个关键方面。尽管通过各种手段研究这些相互作用和过程的组成部分，但在这个项目中，可以使用为此目的收集的新数据对整个时期进行统一和比较的研究。特别是通过对正在迅速发展的大量古环境数据数据库的研究，我们的实验室对此做出了重大贡献。在短期内，这是通过四个相互关联的项目来完成的。首先，我们正在从北极和北方地区开发新的古气候重建，以更好地了解北极的自然变化，并将当前的变暖置于背景下。这项研究使用了全新世早期（5000-9000年前），当时加拿大北极地区相当温暖，作为一个潜在的，尽管不完美的未来模拟，并将详细研究中世纪时期（另一个相对温暖的时期）与今天的比较。由于全球变暖，北极正在发生变化，资源开采对区域的影响也在增加，这项研究将为下个世纪的这些影响提供深入的见解。第二个项目重建了北半球和世界过去2万年的气候变化，将这些结果置于全球背景下。通过更好地量化过去的气候变化，它将使气候科学家能够将当前的气候变化置于适当的背景下。将过去的气候重建与气候模式的输出进行比较，使气候建模者能够改进他们的模式，并能够更好地预测未来。来自加蒂诺山的新数据将确定森林如何应对长期气候变化，以及火灾、大规模伐木和农业等干扰。这些结果可以用于森林管理，因为我们研究的时间尺度是几十年到几百年，当前活动的影响也是如此。此外，我们正在研究该地区的湖泊生态系统在过去是如何变化的，与主要气候变化有关，也与森林组成和土地利用的变化有关。这将有助于了解该地区的湖泊在过去150年里受到了多大的影响。对北美过去15000年人类与环境相互作用的研究将使我们更好地理解欧洲殖民对景观的影响。通过更详细地研究欧洲人到来之前的植被性质，并确定美洲原住民如何影响环境，以及过去气候变化对其的影响，我们可以更好地了解当前的活动如何改变全球碳平衡，因为我们需要在工业时代的广泛影响之前对森林性质有一个正确的基线。

This research program uses a paleoenvironmental approach to understand climate variability and climate change impacts on terrestrial and freshwater ecosystems. The purpose of the research program is to study the scales and mechanisms of climate variability and to quantify terrestrial and freshwater ecosystem interactions and response to long-term climate variability. The role of human impacts, on a continuum from the first arrival of humans on the continent as the Ice Age was ending, to the introduction of extensive agriculture, the arrival of Europeans and rapid industrialization is a key aspect of the research program Although components of these interactions and processes are studied through various means, in this project the entire period can be studied uniformly and comparably using new data collected for this purpose, but especially through the study of extensive databases of paleoenvironmental data that are rapidly being developed, and to which our lab has made a significant contribution. In the short-term, this is done through four interrelated projects. First, we are developing new paleoclimate reconstructions from Arctic and Boreal sites, to better understand the natural variability of the Arctic and to place current warming in context. This uses the early Holocene (5000-9000 years ago), when the Canadian Arctic was quite warm, as a potential, although imperfect analogue of the future and will study in the detail the Medieval period (another relatively warm time) in comparison to today. As the Arctic is changing due to global warming and regional impacts due to resource extraction are increasing, this study will provide insight into what will be these effects in the coming century. These results are put in a global context by a second project reconstructing climate changes of the past 20000 years in the Northern Hemisphere and the world. By better quantifying past climate variability, it will enable climate scientists to place current climate variability in its proper context. Comparing past climate reconstructions with the output of climate models enables climate modellers to improve their models and be able to better forecast the future. New data from the Gatineau Hills will determine how forests respond to long term climate change, and to disturbances such as fire, extensive logging and agriculture. These results can be used in forest management, as the timescales of our study is decades to centuries as is the impact of current activities. In addition, we are studying how lake ecosystems of the region have varied in the past, in relation to the major climate changes, and also by changes in forest composition and land use. This will help to understand how much the lakes of the area have been impacted by events of the past 150 years. A study of the interactions of humans and the environment over the past 15000 in North America will enable us to better understand the impact of European colonization on the landscape. By studying in more detail the nature of the vegetation before the arrival of Europeans, and determining how Native Americans impacted the environment, and were impacted by climate changes of the past, we can better understand how current activities are changing the global carbon balance, as we need a correct baseline on the nature of the forests before the extensive impacts of the industrial age.