FAPESP - Amazon PyroCarbon: Quantifying soil carbon responses to fire and climate change

FAPESP - Amazon PyroCarbon：量化土壤碳对火灾和气候变化的反应

• 批准号: NE/W001691/1
• 负责人: Ted Feldpausch
• 金额: $ 83.21万
• 依托单位: UNIVERSITY OF EXETER
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW001691%2F1
• 关键词: FAPESP; Amazon; PyroCarbon; Quantifying; soil

Wildfires are becoming the new normal across Amazonia. Deforestation is transforming the region at a rate of around 10,000 square km/year (half the area of Wales), and now the area degraded annually -forest logged and burned but not cut down-is greater than the area deforested. Fire has historically been rare in Amazonia, meaning that the forests are not adapted to fire and the trees often die from fires - releasing carbon (C) back to the atmosphere and amplifying global climate change. Burning of tropical forests is already releasing more climate-warming carbon dioxide than fossil fuel burning in the whole of Europe. Trees in Amazonia contain around 7x more C than humans are releasing every year, and soils contain the same amount again, so it is vital to understand what is happening to this C and minimize emissions. As vegetation sheds its leaves, branches, and roots, or dies, some of the C released remains in the soil, and some is later decomposed and released back to the atmosphere. Carbon exists in the soil in many different forms, from new inputs from decomposing plant material to ancient C formed over millennia. Burning adds pyrogenic carbon (PyC) to the soil, a partially burnt form of C that is resistant to decomposition and could make the soil more fertile. Because soil C takes a long time to form, its conservation is particularly important. Despite the widespread increase in fire in Amazonia, there have been few measurements of soil C fractions and dynamics in burned areas - most have focussed on natural forests. Burned forests will have different composition, forest structure, and C dynamics. Understanding how different soil C fractions are formed and lost is crucial to understand how fire and climate change affect C storage. We propose to make major advances in understanding fire impacts, including the processes that affect the type and quantifies of soil C formed, and how C gains/losses vary over time, with soil type, and climate. We will combine new measurements with innovative modelling to inform land management strategies and C budgets.We have already collected data from across Amazonia in intact forests that have not recently burned. Crucially our project will collect a new, comprehensive dataset from human-modified forests, including logged, burned and abandoned land. We will use an approach known as a chronosequence, where we take samples at sites that were burnt at different times in the past, so we can see how the soil C has changed after e.g. 1 year, 2 years, or up to 20 years after a fire. This will then be used to develop a state-of-the-art land surface model, JULES, which forms part of the UK Earth System Model. At our sample sites, we will evaluate how different burn severities affect soil C, both in surface and deep soils, and how these change over time post-burning and with soil, climate, and land-use such as logging. At 3 focal sites, we will take detailed measurements of the decomposition rate of the C over 4 years, comparing measurements with different land-use, burn severity and wet vs dry seasons. Knowing what forms C takes after a fire and how fast it decomposes under different conditions will enable us to build these processes into the JULES model. We will model PyC globally for the first time and make projections of land C changes in Amazonia over the next ~40-60 years under different management practices. As well as transforming scientific understanding of post-fire soil C and its resilience to climate and management, our project will inform socio-environmental planning for sustainable resource use to conserve soil C. We will work with regional partners, fire managers, state and national policymakers to integrate our findings into decision-making to minimise negative fire impacts. Due to the Amazon Basin-scale of our work, these strategies are a crucial step to limit the risk of large-scale loss of soil C.

野火已成为整个亚马逊地区的新常态。森林砍伐正在以约10,000平方公里/年（威尔士面积的一半）的速度转变该区域，现在该地区每年被降级 - 预订并被燃烧，但不高于砍伐区域。历史上，大火在亚马逊岛很少见，这意味着森林并不适应火，树木经常死于大火 - 将碳（C）释放回气氛并扩大全球气候变化。与整个欧洲的化石燃料相比，热带森林的燃烧已经在释放更多的气候二氧化碳。亚马逊的树木比人类每年释放的C含有大约7倍的C，并且土壤再次包含相同的数量，因此了解该C发生了什么并最大程度地减少排放量至关重要。当植被脱落其叶子，树枝，根或死亡时，释放的一些C仍留在土壤中，后来分解并释放回了大气。碳在土壤中以多种不同形式存在，从分解植物材料到数千年来形成的古代C。燃烧在土壤中添加了热源碳（PYC），这是一种抗分解能力的部分燃烧形式，可以使土壤更肥沃。由于土壤C需要很长时间才能形成，因此其保护尤为重要。尽管亚马逊地区的火灾广泛增加，但在被烧毁地区的土壤C部分和动态的测量很少 - 大多数集中在天然林上。燃烧的森林将具有不同的组成，森林结构和C动力学。了解不同的土壤c分数的形成和丢失对于了解火灾和气候变化如何影响C存储至关重要。我们建议在理解火灾影响方面取得重大进展，包括影响所形成的土壤C类型和量化的过程，以及C随着时间的流逝，土壤类型和气候的增加/损失如何变化。我们将将新的测量结果与创新的建模相结合，以告知土地管理策略和C预算。我们已经收集了来自亚马逊群岛的整个完整森林中的数据，这些森林最近尚未燃烧。至关重要的是，我们的项目将从人类改造的森林中收集一个新的，全面的数据集，包括已记录，燃烧和废弃的土地。我们将使用一种称为Chronosequence的方法，在该方法中，我们在过去在不同时间燃烧的地点采集样品，因此我们可以看到土壤C之后的土壤C发生了变化。大火后1年，2年或最多20年。然后，这将用于开发最先进的陆地表面模型Jules，该模型构成了英国地球系统模型的一部分。在我们的样本地点，我们将评估不同的燃烧严重程度如何影响土壤中的土壤C，以及在燃烧后以及土壤，气候和土地利用（例如伐木）之后随着时间的流逝而变化。在3个焦点地点，我们将在4年内详细测量C的分解速率，并将其与不同的土地使用，烧伤严重程度和湿季节与干燥季节进行比较。知道C在大火之后采取的形式以及在不同条件下分解的速度将使我们能够将这些过程构建到Jules模型中。我们将首次在全球对PYC进行建模，并在不同的管理实践下在接下来的40 - 60年中对亚马逊的土地变化进行预测。除了改变对火后土壤C的科学理解及其对气候和管理的韧性外，我们的项目还将为可持续资源使用以保护土壤的社会环境计划，以保护土壤。我们将与区域合作伙伴，消防经理，州和国家决策者合作，将我们的发现集成到决策中，以最大程度地减少消极影响。由于我们工作的亚马逊盆地规模，这些策略是限制大规模损失土壤C的风险的关键步骤。

项目成果

From past to present : impacts of fire on Amazonian forests

从过去到现在：火灾对亚马逊森林的影响

• 发表时间: 2022
• 作者: Vedovato L.

A stoichiometric approach to estimate sources of mineral-associated soil organic matter

• DOI: 10.1111/gcb.17092
• 发表时间: 2024-01-01
• 期刊: GLOBAL CHANGE BIOLOGY
• 影响因子: 11.6
• 作者: Chang，Yi;Sokol，Noah W.;Ding，Fan
• 通讯作者: Ding，Fan

Forest Fire History in Amazonia Inferred From Intensive Soil Charcoal Sampling and Radiocarbon Dating

• DOI: 10.3389/ffgc.2022.815438
• 发表时间: 2022-05
• 期刊: Quaternary Science Reviews
• 影响因子: 4
• 作者: T. Feldpausch;L. Carvalho;K. Macario;P. Ascough;César F. Flores;E. H. Coronado;Michelle Kalamandeen;O. Phillips;R. Staff

Effect of tree wood density on energy release and charcoal reflectance under constant heat exposure

恒定热暴露下树木密度对能量释放和木炭反射率的影响

• DOI: 10.1071/wf22156
• 发表时间: 2023
• 期刊: International Journal of Wildland Fire
• 影响因子: 3.1
• 作者: Crawford A

Soil pyrogenic carbon in southern Amazonia: Interaction between soil, climate, and above-ground biomass

• DOI: 10.3389/ffgc.2022.880963
• 发表时间: 2022-10
• 作者: E. A. de Oliveira;T. Feldpausch;B. Marimon;P. Morandi;O. Phillips;M. Bird;A. A. Murakami-A.;L. Arroyo;C. Quesada;B. H. Marimon‐Junior