Ecosystems on the edge: the ecology of deciduous forest ecosystems near their northern limit in Quebec

边缘生态系统：魁北克北部边界附近的落叶森林生态系统的生态

基本信息

批准号：
36637-2008
负责人：
Fyles, James
金额：
$ 1.29万
依托单位：
McGill University
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2009
资助国家：
加拿大
起止时间：
2009-01-01 至 2010-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=421021
关键词：
Ecosystems edge ecology deciduous forest

项目摘要

Understanding the factors that control how forest ecosystems function near their northern limits is critical to predicting how forests will respond to climate change. This research aims to increase understanding of the relative role of climate, soil and biotic factors in controlling the distribution of forests dominated by trembling aspen (Populus tremuloides) in the James Bay region of northern Quebec. Our recent work in aspen and black spruce forests in the northern Quebec have shown that establishment and growth of trees depends on the interacting effects of vegetation, soil organic matter decomposition and accumulation, soil nutrition, and site disturbance. We have developed a new approach for multivariate analysis of spatial pattern that improves detection of ecological relationships in the field. The new research will build on these lines of enquiry. The proposed program will study the roles of climate, site, and carbon and nutrient cycling in controlling the distribution of aspen forests across a climatic transect from central Quebec to the northern limit of their range. 'Biocentric' climatic indices will be developed to define the 1300 km transect. Aspen stands will be characterized by tree growth rates, nutrient cycling and soil properties. Patterns of change in these variables with increasing latitude will be compared to patterns of change in climatic indices to test the hypothesis that climate is the dominant control. Since trees respond in an integrated way to multiple stresses, the effect of climate depends on the effects of other factors; favorable conditions in site or soil factors can allow aspen to grow in unfavorable climate. This will be tested in using landscape patterns of aspen forests near their northern limit. We will use C and N isotopic signatures to better gain a better understanding of whether the distribution of aspen forests in changing with changing climate. Overall, the research will increase knowledge of the relative roles of climatic and non-climatic factors in determining the distribution of deciduous forest ecosystems in the north and will provide a better foundation for predicting the effects of climate change.

了解控制森林生态系统在其北部边界附近如何运作的因素对于预测森林将如何应对气候变化至关重要。本研究旨在加深对气候、土壤和生物因素在控制魁北克北部詹姆斯湾地区以颤杨（Populus tremuloides）为主的森林分布方面的相对作用的了解。我们最近在魁北克省北部的白杨和黑云杉森林中进行的研究表明，树木的生长和生长取决于植被、土壤有机质分解和积累、土壤营养和场地干扰的相互作用。我们开发了一种空间格局多变量分析的新方法，可以改进对实地生态关系的检测。新的研究将建立在这些调查的基础上。拟议的计划将研究气候、地点以及碳和养分循环在控制白杨森林在从魁北克中部到其范围北部边界的气候横断面的分布中的作用。将制定“生物中心”气候指数来定义 1300 公里的横断面。白杨林的特点是树木生长速度、养分循环和土壤特性。这些变量随纬度增加的变化模式将与气候指数的变化模式进行比较，以检验气候是主导控制的假设。由于树木对多种压力做出综合反应，因此气候的影响取决于其他因素的影响。有利的场地条件或土壤因素可以使白杨在不利的气候下生长。这将通过使用靠近其北部边界的白杨森林的景观模式进行测试。我们将利用C和N同位素特征来更好地了解白杨森林的分布是否随着气候变化而变化。总体而言，该研究将增加人们对气候和非气候因素在确定北部落叶森林生态系统分布中相对作用的认识，并为预测气候变化的影响提供更好的基础。