The role of climate-driven factors on carbon and phosphorus sequestrations in lake sediments and soils

气候驱动因素对湖泊沉积物和土壤中碳和磷固存的作用

• 批准号: RGPIN-2020-06184
• 负责人: Dittrich, Maria
• 金额: $ 2.62万
• 依托单位: University of Toronto
• 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=762164
• 关键词: role; climate; driven; factors; carbon

The past decade has witnessed a dramatic increase in the recognition of the role of inland waters in the global carbon (C) cycle. Since in inland waters a large amount of carbon is sequestered in sediments or emitted to the atmosphere, only half from the total C transported over the terrestrial ecosystem reaches the oceans. The long-term C sinks in lake and river sediments have rarely been assessed due to the complexity of measurements and the difficulty of extrapolating results from one system to another. Even though the terrestrial-aquatic continuum is one of the key uncertainties in global and local C and phosphorus (P) balance, neither a speciation of C nor P loadings from catchments have been estimated so far. Carbon and phosphorus speciation trigger the portions of the total C and P that will remain in the sediments. Over centuries accumulated P legacy in soils is a hidden pool entering our watersheds and ending up in lakes, impacting the C and P cycles during decades and perhaps even longer. Thus, it is imperative to remediate the P legacy in watersheds and contribute to a circular P economy, an economy that is designing out waste and pollution, keeping materials in use and regenerating natural systems. The long-term goals of my program are to understand and identify potential C sources and sinks in the terrestrial-aquatic continuum, to estimate P legacy in the terrestrial-aquatic continuum, and to elucidate and develop techniques for C sequestration and a circular P economy. This proposal focuses on multidisciplinary research of C and P sequestration along the terrestrial-aquatic continuum and has the following short-term objectives: O1: To examine the impact of climate-driven factors such as air temperature, precipitation and ice cover on C and P burial fluxes in lake sediments. O2: To estimate a speciation of C and P loadings from watersheds under extreme weather events. O3: To elucidate legacy P release from soils and to develop a sustainable bioremediation technique to capture and re-use P. I will combine field and laboratory experiments and modeling studies to obtain insight into biogeochemical processes ranging from the molecular to complex environmental system scales. The anticipated findings of the changes in C and P sequestration in lake sediments due to the dynamics of climate-driven factors, such as warming and the frequencies of extreme events, will contribute to closing the fundamental knowledge gap in the field of C and P biogeochemistry and offer missing data for the global modeling. The results will provide an enhanced insight into the consequences that these processes have on management strategies for the improvement of water quality. Importantly, our expected results will foster the development of new technology for C sequestration and P remediation in a current time of P mineral resource scarcity. This research will strengthen Canada's ability in the area of watershed and freshwater ecosystem management.

过去十年，人们对内陆水域在全球碳 (C) 循环中的作用的认识急剧提高。由于在内陆水域中，大量碳被封存在沉积物中或排放到大气中，因此通过陆地生态系统输送的总碳中只有一半到达海洋。由于测量的复杂性以及将结果从一个系统外推到另一个系统的困难，湖泊和河流沉积物中的长期碳汇很少被评估。尽管陆地-水生连续体是全球和局部碳和磷 (P) 平衡的关键不确定因素之一，但迄今为止，尚未对流域的碳和磷负荷的形态进行估计。碳和磷的形态会触发总碳和磷中残留在沉积物中的部分。几个世纪以来，土壤中积累的磷残留物成为一个隐藏的水池，进入我们的流域并最终流入湖泊，在数十年甚至更长的时间里影响碳和磷的循环。因此，当务之急是修复流域中的磷残留，并为循环磷经济做出贡献，这种经济旨在消除废物和污染，保持材料的使用和再生自然系统。 我的计划的长期目标是了解和确定陆地-水生连续体中潜在的碳源和汇，估计陆地-水生连续体中的磷遗留量，并阐明和开发碳封存和循环磷经济技术。 该提案重点关注陆地-水生连续体碳和磷固存的多学科研究，并具有以下短期目标： O1：研究气温、降水和冰盖等气候驱动因素对碳和磷的影响湖泊沉积物中的埋藏通量。 O2：估计极端天气事件下流域的 C 和 P 负荷形态。 O3：为了阐明土壤中遗留的磷释放，并开发一种可持续的生物修复技术来捕获和再利用磷。我将结合现场和实验室实验以及建模研究，以深入了解从分子到复杂环境系统规模的生物地球化学过程。由于气候驱动因素（例如变暖和极端事件的频率）的动态，湖泊沉积物中碳和磷固存变化的预期结果将有助于缩小碳和磷生物地球化学领域的基础知识差距并为全局建模提供缺失数据。研究结果将有助于深入了解这些过程对改善水质的管理策略所产生的影响。重要的是，我们的预期结果将促进在当前磷矿产资源匮乏的情况下碳封存和磷修复新技术的发展。这项研究将加强加拿大在流域和淡水生态系统管理领域的能力。