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

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增加。由于在内陆水域，大量的碳被隔离在沉积物中或排放到大气中，在陆地生态系统输送的总碳中，只有一半进入了海洋。由于测量的复杂性和将结果从一个系统外推到另一个系统的困难，很少对湖泊和河流沉积物中的长期碳汇进行评估。尽管陆地-水生连续体是全球和局部C和P平衡的主要不确定性之一，但到目前为止，还没有估计到来自流域的C或P负荷的形态。碳和磷的形态形成触发了总碳和磷的一部分，这些部分将留在沉积物中。几个世纪以来，土壤中积累的磷是一个隐藏的池塘，进入我们的流域，最终进入湖泊，影响数十年甚至更长时间的C和P循环。因此，必须修复流域的磷遗产，促进循环磷经济，这是一种设计出废物和污染、保持材料使用和再生自然系统的经济。 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碳汇，估计陆地-水生连续体中的磷遗产，并阐明和开发碳封存和循环磷经济的技术。 该建议侧重于陆地-水生连续体碳和磷固存的多学科研究，并有以下短期目标： O1：研究气候驱动因素如气温、降水和冰盖对湖泊沉积物中碳和磷埋藏通量的影响。 O2：估计极端天气事件下流域碳和磷负荷的形态。 臭氧：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重新利用磷。 我将结合现场和实验室实验和模型研究，深入了解从分子到复杂环境系统尺度的生物地球化学过程。由于气候驱动因素的动态变化，如气候变暖和极端事件的频率，湖泊沉积物中碳和磷的固存变化的预期结果将有助于弥合碳和磷生物地球化学领域的基本知识差距，并为全球模拟提供缺失的数据。这些结果将使人们更深入地了解这些进程对改善水质的管理战略所产生的影响。重要的是，我们的预期结果将促进在当前磷矿资源稀缺的情况下开发碳封存和磷修复的新技术。这项研究将加强加拿大在分水岭和淡水生态系统管理方面的能力。

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.