Dynamics of carbon capture in Scottish and Irish peatlands over the past centuries

由于泥炭地储存并可能释放大量的碳，预测它们在未来变暖中的作用至关重要（例如，Gallego-Sala等人，2018; Ferretto et al. 2019）。该项目的目的是量化近原始和受损沼泽在过去4-5个世纪的碳动态，并评估碳埋藏率和环境动态之间的可能关系。将利用植物宏体化石和有壳变形虫分析探讨沼泽中碳积累、当地植被和地下水位之间的关系。稳健的年表是必不可少的可靠的百年尺度的重建沼泽内的碳积累。然而，在过去的4-5个世纪里，大气中14 C含量的大的自然和人为变化导致14 C年表不精确，目前基于210 Pb的年表是不灵活的，不能纳入其他日期。该项目将是第一个通过新发表的贝叶斯替代方法（Aquino等人，2018年），以产生增强，准确和更灵活的年表与现实的不确定性估计。将对北方爱尔兰和苏格兰的四个泥炭剖面进行高分辨率调查，以产生过去~500年碳积累的非常详细的时间序列。加上赫顿研究所对沼泽中CO2和CH 4通量的现有当代监测，这将有助于加强对泥炭地的碳通量的估计。通过结合高分辨率的14 C和210 Pb数据，我们将首次能够独立地测试普遍接受的恒定210 Pb通量的假设。如果我们发现不同的210 Pb通量，那么许多现有的基于210 Pb的年表是有缺陷的。因此，这个项目可能会影响泥炭沼泽在碳积累的作用，以及为210铅为基础的研究在世界各地。学生将被要求进行实地考察苏格兰和北方爱尔兰沼泽，进行实验室分析（14 C，210铅，宏化石，有遗嘱的变形虫），并进行一些编程。

Because peatlands store and potentially release large amounts of carbon, predicting their role in future warming is essential (e.g., Gallego-Sala et al., 2018; Ferretto et al. 2019). The aim of this project is to quantify the carbon dynamics in near-pristine and damaged bogs over the past 4-5 centuries, and to assess possible relationships between carbon burial rates and environmental dynamics. Relationships between carbon accumulation, local vegetation and water tables in the bogs will be explored using plant macrofossil and testate amoebae analyses. Robust chronologies are essential for reliable centennial-scale reconstructions of carbon accumulation within bogs. However, large natural and human-made changes in atmospheric 14C content over the past 4-5 centuries cause imprecise 14C chronologies, and current 210Pb-based chronologies are inflexible and incapable of incorporating other dates. This project will be among the first to combine 14C and 210Pb dates through a newly published Bayesian alternative (Aquino et al., 2018), in order to produce enhanced, precise and more flexible chronologies with realistic uncertainty estimates. Four peat profiles in Northern Ireland and Scotland will be investigated at high resolution in order to produce highly detailed time series of carbon accumulation spanning the past ~500 years. Together with existing contemporary monitoring of fluxes of CO2 and CH4 from bogs by the Hutton Institute, this will enable enhanced estimates of carbon fluxes to, within and from peatlands. By combining high-resolution 14C and 210Pb data, we will for the first time be able to independently test the universally accepted assumption of a constant 210Pb flux. If we find varying 210Pb fluxes, then many existing 210Pb-based chronologies are flawed. Thus this project could have implications for the role of peat bogs in carbon accumulation as well as for 210Pb-based studies across the world.The student will be required to undertake fieldwork on Scottish and Northern Irish bogs, perform laboratory analyses (14C, 210Pb, macrofossils, testate amoebae) and undertake some programming.