A process-based model for assessing the impacts of reservoirs and forest harvesting on the carbon budget of aquatic ecosystems

用于评估水库和森林采伐对水生生态系统碳预算影响的基于过程的模型

• 批准号: 322385-2005
• 负责人: Lucotte, Marc
• 金额: $ 12.62万
• 依托单位: Université du Québec à Montréal
• 依托单位国家: 加拿大
• 项目类别: Strategic Projects - Group
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=362335
• 关键词: process; based; model; assessing; impacts

Human activities such as forest harvesting and reservoir impoundment have profoundly impacted the global carbon cycle and, in particular, the atmospheric carbon dioxide (CO2) emissions of land ecosystems. Reservoir impoundment leads to transient and permanent changes in the biogeochemical processes taking place in the water column and the sediments, while forest harvesting strongly modifies the fluxes of terrestrial organic matter (TOM) to aquatic ecosystems. As part of a collaborative effort with governmental partners (Environment Canada, Ministère du Développement Durable, de l'Environnement et des Parcs du Québec), we propose to exploit the latest advances in analytical organic biogeochemistry to develop a fine molecular understanding of (i) the factors responsible for the degradation or sequestration of TOM in aquatic systems, and (ii) the impact of forest harvesting and reservoir impoundment on these factors in terms of changes in the greenhouse gas (GHG) emissions budget at the watershed scale. To generalize our approach and verify our conclusions in aquatic ecosystems across the country, we will develop a new process-based model (Integrated Carbon Cycle Model - ICC model) linking the terrestrial and aquatic ecosystems. This model will use a short list of aquatic biogeochemical tracers to integrate (i) carbon dynamics in lakes or reservoirs, and (ii) modifications in TOM exports due to forest harvesting, to ultimately provide estimates of GHG emission budgets in these contrasting environments. The ultimate goal is to generate and transfer biogeochemical and modeling knowledge to our governmental partners to assist them in determining the long-term effects and significance of such disturbances in relation to anthropogenic GHG emissions or removals from aquatic ecosystems.

森林采伐和水库蓄水等人类活动深刻影响了全球碳循环，特别是陆地生态系统的大气二氧化碳（CO2）排放。水库蓄水导致水柱和沉积物中发生的生物地球化学过程发生短暂和永久性的变化，而森林采伐则强烈改变陆地有机质（TOM）向水生生态系统的通量。作为与政府合作伙伴（加拿大环境部、耐用发展部、魁北克环境与公园）合作的一部分，我们建议利用分析有机生物地球化学的最新进展，以深入了解以下方面：(i) 水生系统中 TOM 降解或封存的因素，以及 (ii) 森林采伐和水库的影响 就流域范围内温室气体（GHG）排放预算的变化而言，对这些因素的蓄积。为了在全国水生生态系统中推广我们的方法并验证我们的结论，我们将开发一个连接陆地和水生生态系统的新的基于过程的模型（综合碳循环模型 - ICC 模型）。该模型将使用简短的水生生物地球化学示踪剂列表来整合 (i) 湖泊或水库中的碳动态，以及 (ii) 由于森林采伐而导致的 TOM 出口变化，最终提供这些对比环境中温室气体排放预算的估计。最终目标是生成生物地球化学和建模知识并将其转让给我们的政府合作伙伴，以帮助他们确定此类干扰与人为温室气体排放或水生生态系统清除的长期影响和重要性。