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

在过去十年中，人们对内陆沃茨在全球碳（C）循环中的作用的认识急剧增加。由于在内陆沃茨，大量的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。由于测量的复杂性和从一个系统到另一个系统的外推结果的困难，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）平衡的关键不确定性之一，但到目前为止，还没有对集水区的碳和磷的物种形成进行估计。碳和磷的形态触发的总C和P的部分，将留在沉积物中。几个世纪以来，土壤中积累的磷遗产是一个隐藏的水池，进入我们的流域并最终进入湖泊，影响数十年甚至更长时间的C和P循环。因此，当务之急是修复流域的磷遗产，并促进循环磷经济，这是一种设计废物和污染，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潜在的C源和汇在陆地-水生连续体，估计P遗产在陆地-水生连续体，并阐明和开发技术的C封存和循环P经济。 该提案侧重于碳和磷固存沿着陆地-水生连续体的多学科研究，并有以下短期目标：O 1：研究气候驱动的因素，如空气温度，降水和冰盖对湖泊沉积物中的碳和磷埋藏通量的影响。 O2：估计极端天气事件下流域C和P负荷的形态。O3：为了阐明传统的磷从土壤中释放，并开发一种可持续的生物修复技术，以捕获和再利用P. I将结合联合收割机现场和实验室实验和建模研究，以深入了解从分子到复杂的环境系统尺度的地球化学过程。由于气候驱动因素的动态变化，如变暖和极端事件的频率，湖泊沉积物中C和P固存的预期结果，将有助于弥补在C和P地球化学领域的基础知识差距，并为全球模拟提供缺失的数据。结果将提供一个更深入的了解，这些过程对水质改善的管理战略的后果。重要的是，我们的预期结果将促进新技术的发展，碳封存和磷修复在当前的磷矿产资源稀缺。这项研究将加强加拿大在流域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.