Shifting patterns? Understanding peatland resilience from shifts in small scale microform patterns (SPURT)

泥炭地在全球碳循环中发挥着关键作用。它们储存了大量的大气二氧化碳，但也排放甲烷，两者都是强效的温室气体。然而，到目前为止，还不确定碳通量将如何随着气候变化而变化。大多数泥炭地都呈现微地形，形成一种干湿微地形（微地形）模式，每种微地形都有不同的温室气体通量。因此，微形态分布的变化可能会对泥炭地的碳收支产生重大影响。因此，一个重要的遗留问题是缩微品的图案如何随着时间的推移而发展以应对气候变化。本项目将通过调查古生态泥炭记录来解决这个问题。微形态类型之间的变化将通过放射性碳测年法从宏观化石组成中确定，并与过去气候变化的时间有关。将在12个泥炭芯中研究微形态变化、水力特性、分解和碳积累之间的关系，捕获泥炭地的空间变化。将使用一种新的方法来量化微形态对气候变化的适应能力，该方法将微形态和泥炭水分指标的变化与从植物生物标志物的同位素特征重建的降水平衡变化进行比较。这项研究的结果将阐明长期的微形态动力学的控制，提高在气候变化下泥炭地碳预算预测的准确性。

Peatlands play a key role in the global carbon cycle. They store large amounts of atmospheric carbon dioxide, but also emit methane, both potent greenhouse gases. However, to date it is uncertain how carbon fluxes will change in response to climate change. Most peatlands exhibit microtopography, creating a pattern of wet and dry microsites (microforms), and each microform has different greenhouse gas fluxes. Thus, a shift in microform distribution may have large consequences for the peatland carbon budget. An important remaining question is therefore how patterns of microforms develop over time in response to climate change. This project will address this question by investigating paleo-ecological peat records. Shifts between microform types will be identified from macrofossil composition, dated through radiocarbon dating, and related to the timing of past climate changes. The relation between microform shifts, hydraulic properties, decomposition, and carbon accumulation will be studied in twelve peat cores, capturing spatial variation across the peatland. Microform resilience to climate change will be quantified using a novel method comparing the timing of shifts in microforms and peat moisture indicators with changes in precipitation balance reconstructed from isotopic signatures of plant biomarkers. The results of this study will clarify the controls on long-term microform dynamics, increasing the accuracy of predictions of peatland carbon budgets under a changing climate.