Turning up the heat in a northern hardwood: Response of soils and trees to summer and winter climate change

提高北方硬木的热量：土壤和树木对夏季和冬季气候变化的反应

• 批准号: RGPIN-2020-04931
• 负责人: Belanger, Nicolas
• 金额: $ 2.4万
• 依托单位: TÉLUQ
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=764752
• 关键词: Turning; up; heat; northern; hardwood

Climate change is threatening the capacity of forests to provide its various services by causing, among other events, milder winters and increased freeze-thaw cycling in the soil and drier and warmer summers that create water stress for plants. Canada is committed to maintaining forests that are resilient to current and imminent global change. To forecast forest response to climate change, scientists have recently recognized the need to develop models not just based on regional climates, but also based on the reorganization of interactions between tree species and between trees and soils as well as possible feedbacks. The long-term objective of this research program is to characterize soil-plant interrelationships and nutrient cycling in eastern Canadian temperate deciduous forests under a changing climate. In the next 5 years, the research program will continue to strengthen the predictive framework of the response of forests to climate change by running novel manipulative field experiments to assess how soil warming during the growing season and decreased snow cover during winter affect soil carbon dynamics at the northern limit of temperate deciduous forests. To do so, changes in soil organic carbon levels, forms and stability, organic carbon from soil microbial biomass, soil respiration, leaf litter decomposition rates, fine root biomass production and microbial communities and dissolved organic carbon leaching rates will be measured under various treatments which include growing season soil warming only, winter snow removal only, a combination of both and reference (control) plots. Soil nutrient availability using ion-exchange resins and conventional soil chemical extraction methods as well as seed germination rates, seedling survival, growth, water use, foliar nutrition and root mycorrhizal fungi associations will also be assessed. These experiments are not matched elsewhere due to site location, number of replicated plots, the fact that both growing season and winter climate change are experimentally tested and that interactions between trees and soils at recruitment and juvenile growth stages are investigated under experimental climate change in the field. This research program is thus a very unique and essential piece of research for: (1) measuring present and estimating future states and dynamics of forests, (2) improving simulation models of forest response to climate change and thus pin-pointing the best possible adaptation strategies to climate change, and (3) training HQPs to gain further understanding of forest functioning under a changing climate and transfer this knowledge to the public and private forest sectors involved in forest management decision-making.

气候变化正在威胁森林提供各种服务的能力，因为除其他事件外，气候变化还导致冬季变暖，土壤中的冻融循环增加，夏季变得更加干燥和温暖，这给植物造成了水分压力。加拿大致力于维护对当前和迫在眉睫的全球变化具有弹性的森林。为了预测森林对气候变化的反应，科学家们最近认识到，不仅需要根据区域气候，而且需要根据树种之间、树木与土壤之间的相互作用以及可能的反馈来建立模型。这项研究计划的长期目标是研究加拿大东部温带落叶林在气候变化下的土壤-植物相互关系和养分循环。在接下来的5年里，该研究计划将继续加强森林对气候变化反应的预测框架，通过开展新的操纵性田间实验来评估生长季节土壤变暖和冬季降雪如何影响温带落叶森林北部边界的土壤碳动态。为此，将测量不同处理下土壤有机碳水平、形态和稳定性、来自土壤微生物生物量的有机碳、土壤呼吸、凋落物分解速率、细根生物量和微生物群落以及溶解有机碳淋失率的变化，这些处理包括仅生长季土壤变暖、仅冬季除雪、两者结合和参考(对照)样地。还将评估使用离子交换树脂和传统土壤化学提取方法的土壤养分有效性以及种子发芽率、幼苗存活、生长、水分利用、叶片营养和根部菌根真菌协会。这些试验在其他地方是无与伦比的，原因是场地位置、重复小区的数量、生长季和冬季气候变化都经过了实验测试，以及在田间试验气候变化下调查了幼树和幼虫生长阶段树木与土壤的相互作用。因此，这项研究计划是一项非常独特和必要的研究：(1)测量和估计森林的现状和动态，(2)改进森林对气候变化反应的模拟模型，从而确定最好的气候变化适应战略，以及(3)培训HQP，以进一步了解气候变化下森林的功能，并将这些知识传递给参与森林管理决策的公共和私营森林部门。