Unveiling the Secrets of Peatlands for Climate Change Mtigation

揭开泥炭地减缓气候变化的秘密

• 批准号: 2888962
• 金额: --
• 依托单位: University of Aberdeen
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2888962
• 关键词: Unveiling; Secrets; Peatlands; Climate; Change

The Scottish peatlands (i.e. mires, fen and bog) cover about 20% of the country, storing approximately 1600 million tonnes of carbon in the soils, and therefore, represent an essential component of GHG budget at the Holocene time scale (Frolking et al., 2006). Peatlands also play important roles in water quality and supply, host a range of unique species, provide spaces for recreation and preserve a record of past environments and human activity (Bain et al., 2011). However, it is estimated that over 80% of the Scottish peatlands are degraded (Scotland soils, 2022). Un-degraded peatlands accumulate soil organic matter and act as a sink ecosystem for atmospheric CO2 due to the absence of aerobic decomposition and associated CO2 emissions under waterlogged soil conditions (Dise, 2009). Nevertheless, managed peatlands (e.g. drained and cultivated or afforested) show a high variability in GHG emissions at both spatial and temporal levels due to active systems in soil moisture dynamics, redox potential, availability of substrate materials and man-made alterations to hydrology and vegetation (Schrier-Uijl et al., 2010; Abdalla et al., 2014; Abdalla et al., 2016). There is a concern that degraded peatlands may significantly exacerbate anthropogenic climate change through release of CO2 from soils (Hooijer et al, 2010). This concern is currently motivating extensive attempts to conserve and restore peatlands in Scotland and around the world. On one hand, restoring degraded peatlands can reconnect them to their catchments and thereby, decreases CO2 emissions and increases carbon storage (Horsburgh et al., 2022). On the other hand, restoration by rewetting increases CH4 emissions (which has a higher radiative forcing than CO2) by 46% compared to the original pre-management CH4 emissions (Abdalla et al., 2016). However, it is still not clear how restoration affects net GHG emissions (i.e. balance between GHG emissions and carbon storage). This project will use experimental data, process modelling and meta-analyses to assess net GHG emissions by investigating both GHG emissions and carbon storage to fill this gap in knowledge. Further, the attribution of GHG emissions to anthropogenic and natural drivers is a great challenge, and is a prerequisite to successfully assess the potential to reduce the emissions from peatlands.To the best of our knowledge, until this date, the impact of degraded or restored Scottish peatlands on net GHG emissions under baseline and climate change are not fully quantified/ mapped, nor potential restoration techniques modelled. This study will achieve the following objectives:1) Create maps of baseline annual net GHG emissions from the Scottish peatlands; 2) Create maps of annual net GHG emissions from peatlands under climate change; 3) Map and investigate the impacts of drainage/ restoration on net GHG emissions; and 4) Investigate sensitivity of GHG emissions from the Scottish's peatlands to anthropogenic and natural drivers.

苏格兰泥炭地（即沼泽，沼泽和沼泽）覆盖了该国约20%的土地，在土壤中储存了约16亿吨碳，因此，代表了全新世时间尺度上温室气体预算的重要组成部分（Frolking等人，2006年）。泥炭地在水质和供水方面也发挥着重要作用，拥有一系列独特的物种，提供娱乐空间，并保存了过去环境和人类活动的记录（Bain等人，2011年）。然而，据估计，超过80%的苏格兰泥炭地退化（苏格兰土壤，2022年）。未退化的泥炭地积累了土壤有机质，并作为大气CO2的汇生态系统，因为在积水土壤条件下没有有氧分解和相关的CO2排放（Dise，2009年）。尽管如此，由于土壤水分动态、氧化还原电位、基质材料的可用性以及人为改变水文和植被等方面的活跃系统，管理的泥炭地（例如排水和耕作或造林）在空间和时间水平上显示出温室气体排放的高度可变性（Schrier-Uijl等人，2010; Abdalla等人，2014; Abdalla等人，2016年）。人们担心，退化的泥炭地可能会通过土壤释放二氧化碳而严重加剧人为气候变化（Hooijer等人，2010年）。这一问题目前正在激励苏格兰和世界各地广泛尝试保护和恢复泥炭地。一方面，恢复退化的泥炭地可以将其重新连接到其集水区，从而减少CO2排放并增加碳储存（Horsburgh等人，2022年）。另一方面，通过再湿润的恢复使CH 4排放量（其具有比CO2更高的辐射强迫）与原始管理前的CH 4排放量相比增加了46%（Abdalla等人，2016年）。然而，恢复如何影响温室气体净排放（即温室气体排放与碳储存之间的平衡）仍不清楚。该项目将使用实验数据、过程建模和元分析，通过调查温室气体排放和碳储存来评估温室气体净排放，以填补这一知识空白。此外，温室气体排放的人为和自然驱动因素的属性是一个巨大的挑战，是成功评估减少泥炭地排放的潜力的先决条件。据我们所知，到目前为止，苏格兰泥炭地退化或恢复对基线和气候变化下的温室气体净排放量的影响没有完全量化/映射，也没有潜在的恢复技术建模。本研究将实现以下目标：1）创建苏格兰泥炭地的基线年度净温室气体排放量地图; 2）创建气候变化下泥炭地的年度净温室气体排放量地图; 3）绘制并调查排水/恢复对净温室气体排放量的影响;以及4）调查苏格兰泥炭地温室气体排放对人为和自然驱动因素的敏感性。