The effects of fire on peatland carbon stocks and dynamics

火灾对泥炭地碳储量和动态的影响

• 批准号: NE/F001770/1
• 负责人: Lisa Belyea
• 金额: $ 16.53万
• 依托单位: Queen Mary University of London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FF001770%2F1
• 关键词: effects; fire; peatland; carbon; stocks

Between 15 and 17 April 2007, a human-induced fire disturbed around 55 km2 of the Galloway Forest Park in southwest Scotland. The burn area included the Silver Flowe National Nature Reserve, a large blanket bog which has a great diversity of vegetation and hummock-hollow patterning. This event provides an unprecedented opportunity to investigate the immediate impacts of fire on peatland carbon stocks, as well as the longer-term changes in peat physical structure, vegetation and below-ground (decomposer) communities that occur after fire. Globally peatlands store a huge amount of carbon as soil organic matter (peat). Over the next decades, fire frequency in peatland-dominated regions is likely to increase as a result of human-induced global warming. By burning the peat, fire can release carbon stocks to the atmosphere as 'greenhouse gases', possibly amplifying global warming further. Conversely, fire can also lead to thermal alteration ('charring') of peat, converting it to a form which is highly resistant to decomposition and therefore protected from release to the atmosphere. Over the longer term, post-fire changes in surface characteristics (soil physical properties, water chemistry, vegetation, decomposer communities) may either increase or decrease the ability of peatlands to store carbon. The overall aim of this study is to improve our understanding of how peatland characteristics mediate the direct impact of fire on carbon stocks, as well as longer-term recovery of carbon-storing ability. We will assess the immediate impact of fire by quantifying the amount of organic matter lost by direct combustion and the amount 'charred' or thermally altered. To do this, we will collect short (50 cm) cores from a range of vegetation types and topographic features that were burned, and then analyse burned and unburned sections of the cores using a range of chemical methods. We predict that areas with large open water pools will be protected from fire impacts, whereas areas dominated by mosses that dry out during droughts will be affected most severely. To enable long-term monitoring of post-fire recovery, we will set up permanent sampling stations across a range of vegetation types and topographic features, in both burned and unburned (control) sites. At each sampling station, we will install equipment that automatically records soil temperature and water-table level. At three times over the year, we will take samples for water chemistry and record changes in vegetation; samples will also be collected for analysis of below-ground decomposers (bacteria and fungi). Together, these data will give us a picture of how the peatland surface changes, both physically and biologically, after fire. Sampling will begin in the first growing season post-fire (i.e., summer 2007). Further funding will be sought at a later date to allow continuation of long-term monitoring and to investigate specific mechanisms of impact and recovery.

在2007年4月15日至17日之间，苏格兰西南部加洛韦森林公园（Galloway Forest Park）约55公里处的人类诱发的大火扰乱。燃烧区域包括银色的国家自然保护区，这是一个大毯子沼泽，具有大量的植被和空心型构图。该活动提供了一个前所未有的机会，可以调查火灾对泥炭碳库存的直接影响，以及大火后发生的泥炭物理结构，植被和地下（分解）社区的长期变化。全球泥炭地存储大量碳作为土壤有机物（泥炭）。在接下来的几十年中，由于人类引起的全球变暖，以泥炭地为主的地区的火频率可能会增加。通过燃烧泥炭，火可以将碳储量释放到大气中，以“温室气体”，可能会进一步扩大全球变暖。相反，火还会导致泥炭的热改变（“炭化”），将其转化为一种对分解高度耐药性并因此从释放到大气而受到保护的形式。从长远来看，火后表面特征（土壤物理特性，水化学，植被，分解群落）的变化可能会增加或降低泥炭地存储碳的能力。这项研究的总体目的是提高我们对泥炭地特征如何介导火对碳量的直接影响以及碳存储能力的长期恢复的理解。我们将通过量化直接燃烧损失的有机物数量以及“烧焦”或热改变的量来评估火的直接影响。为此，我们将从燃烧的一系列植被类型和地形特征中收集短（50厘米）的核心，然后使用一系列化学方法分析核心的燃烧和未燃烧的部分。我们预测，具有较大开放水池的区域将受到防火影响，而在干旱期间干燥的苔藓主导的区域将受到最严重影响。为了长期监测火灾后恢复，我们将在燃烧和未燃烧的（对照）地点中建立永久性采样站和植被类型和地形特征。在每个采样站，我们将安装自动记录土壤温度和水位水平的设备。在一年中，我们将为水化学和记录植被变化的样品进行样品。还将收集样品以分析地下分解剂（细菌和真菌）。这些数据一起将为我们提供有关泥炭地表面在火灾后在物理和生物学上如何变化的图片。抽样将在火后第一个生长季节开始（即，2007年夏季）。稍后将寻求进一步的资金，以允许继续进行长期监控并调查影响和恢复的特定机制。