Ozone impacts on tropical vegetation; implications for forest productivity (Trop-Oz)

臭氧对热带植被的影响；

• 批准号: NE/R001812/1
• 负责人: Stephen Sitch
• 金额: $ 82.96万
• 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: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FR001812%2F1
• 关键词: Ozone; impacts; tropical; vegetation; implications

In the lower atmosphere ozone (O3) is an important anthropogenic greenhouse gas and is an air pollutant responsible for several billion euros in lost plant productivity each year. Surface O3 has doubled since 1850 due to chemical emissions from vehicles, industrial processes, and the burning of forests. While land ecosystems (primarily forests) are currently slowing down global warming by storing about a quarter of human-released carbon dioxide (CO2) emissions, this could be undermined by rising O3 concentrations impacting forest growth. This in turn would result in more CO2 left in the atmosphere adding to global climate change. Tropical rainforests are responsible for nearly half of global plant productivity and it is in these tropical regions that we are likely to see the greatest expansion of human populations this century. For example, Manaus, in the centre of the Amazon rainforest has seen a population boom in the last 25 years, with the number of residents doubling to just over 2 million people. Alongside this growing population, we see the expansion of O3 precursor emissions from urbanization and high-intensity agricultural areas. The global impacts of changing air pollution on tropical forests are potentially profound. In his seminal work in 2007, PI Sitch and colleagues at the Met Office and Centre for Ecology and Hydrology, were the first to identify the large potential risk to tropical forests from O3 pollution, and how that could in turn accelerate global warming. However, their study presented two major challenges for the research community: 1) the scale of this effect is highly uncertain; as their global modelling study was based on extrapolating plant O3 sensitivity data from temperate and boreal species. This project will address this by providing the first comprehensive set of measurements of O3 effects on plant functioning and growth in tropical trees. Also, as both O3, CO2 and H2O are exchanged between the atmosphere and leaves through a plants stoma, higher levels of CO2 provide plants the opportunity to reduce their stomatal opening, which in turn leads to reduced O3 uptake and damage. This project will for the first time investigate the potential synergistic or antagonistic impacts of climate change (CO2 and Temperature) on O3 responses in tropical forest species. 2) a fundamental challenge in all global vegetation modelling is to accurately represent the structure and function of highly biodiverse ecosystems; global models are generally only able to represent a limited set of generalized plant functional types (e.g. evergreen trees, C4-grasses etc). However, recent collection and synthesis of plant functional trait data (e.g. leaf nutrient concentrations, leaf size and shape) have enabled improved representation of ecology and plant function in global models. A group of scientists, including project partner Johan Uddling, have very recently proposed a unifying theory for O3 sensitivity in temperate and boreal tree species based upon leaf-functional traits. We are in a unique position to take this work forward to test the theory in tropical forest species, and to test the implications of this at the regional and global scale. The inclusion of the relationship between O3 sensitivity and basic plant functional traits in our global vegetation model, JULES (Joint UK Land Environmental Simulator), will lead to a step-change in our ability to assess the impact of air quality on tropical forest productivity and consequences for carbon sequestration. The model will be applied at O3 hotspot locations in tropical forests and together with observed plant trait information and O3 concentrations we will be able to extrapolate beyond the single plant functional type (PFT) paradigm. Global runs of JULES will also enable us to investigate the implications of future O3 concentrations, changes in land-use, and climate change scenarios on the tropical forest productivity and the global carbon sink.

在较低的大气中，臭氧（O3）是一种重要的人为温室气体，是每年造成数十亿欧元的植物生产力损失的空气污染物。自1850年以来，由于车辆，工业工艺和森林燃烧的化学排放，因此O3的表面已翻了一番。尽管土地生态系统（主要是森林）目前正在通过存储大约四分之一的人类释放的二氧化碳（CO2）排放来减慢全球变暖，但这可能会因影响森林增长的O3浓度而受到破坏。反过来，这将导致大气中剩下更多的二氧化碳，从而增加了全球气候变化。热带雨林造成了近一半的全球植物生产力，在这些热带地区，我们很可能会看到本世纪人口最大的扩张。例如，在过去25年中，亚马逊雨林中心的马瑙斯（Manaus）在人口繁荣时期，居民数量增加了一倍，达到了200万以上。除了这个人口不断增长的人群之外，我们看到了城市化和高强度农业地区的O3前体排放量的扩大。不断变化的空气污染对热带森林的全球影响可能是深远的。在2007年的开创性工作中，Pi Sitch及其同事在Met办公室和生态与水文学中心，是第一个从O3污染中确定热带森林的巨大潜在风险，以及如何加速全球变暖。但是，他们的研究给研究界带来了两个主要挑战：1）这种效果的规模高度不确定；由于他们的全球建模研究是基于从温带和北方物种中推断出植物O3敏感性数据的。该项目将通过提供对热带树木植物功能和生长的O3影响的第一组综合测量来解决这一问题。同样，随着O3，CO2和H2O在大气和叶子之间通过植物造口交换，较高的二氧化碳为植物提供了减少气孔开口的机会，进而导致O3的吸收和损害减少。该项目将首次研究气候变化（CO2和温度）对热带森林物种的O3反应的潜在协同或拮抗作用。 2）在所有全球植被建模中的一个基本挑战是准确代表高度生物多样性生态系统的结构和功能；通常，全球模型只能代表有限的广义植物功能类型（例如常绿树，C4草等）。然而，最近收集和合成植物功能性状数据（例如叶片营养浓度，叶子的大小和形状）已使全球模型中生态学和植物功能的表示。一群科学家，包括项目伙伴约翰·乌迪林（Johan Uddling），最近提出了一种基于叶片功能性状的温带和北方树种中O3敏感性的统一理论。我们处于独特的位置，可以将这项工作前进，以测试热带森林物种中的理论，并在区域和全球规模上测试它的含义。在我们的全球植被模型Jules（英国联合土地环境模拟器）中，O3敏感性与基本植物功能性状之间的关系将导致我们评估空气质量对热带森林生产力的影响的能力以及对碳螯合的后果的影响。该模型将应用于热带森林中的O3热点位置，以及观察到的植物性状信息和O3浓度，我们将能够推断出超出单个植物功能类型（PFT）范式。朱尔斯的全球运行还将使我们能够调查未来O3浓度，土地使用变化以及气候变化方案对热带森林生产力和全球碳汇的影响。

项目成果

Examining ozone susceptibility in the genus Musa (bananas).

检查芭蕉属（香蕉）的臭氧敏感性。

• DOI: 10.1071/fp22293
• 发表时间: 2023
• 期刊: FPB
• 作者: Farha MN

Technical note: A simple theoretical model framework to describe plant stomatal "sluggishness" in response to elevated ozone concentrations

技术说明：一个简单的理论模型框架，用于描述植物气孔对臭氧浓度升高的反应“迟缓”

• DOI: 10.5194/bg-15-5415-2018
• 发表时间: 2018
• 期刊: Biogeosciences
• 影响因子: 4.9
• 作者: Huntingford C

Understanding how ozone impacts plant water-use efficiency.

了解臭氧如何影响植物用水效率。

• DOI: 10.1093/treephys/tpab125
• 发表时间: 2021
• 期刊: Tree physiology
• 影响因子: 4
• 作者: Cernusak LA

Increased importance of methane reduction for a 1.5 degree target

• DOI: 10.1088/1748-9326/aab89c
• 发表时间: 2018-05-01
• 期刊: ENVIRONMENTAL RESEARCH LETTERS
• 影响因子: 6.7
• 作者: Collins, William J.;Webber, Christopher P.;Powell, Tom
• 通讯作者: Powell, Tom

The ozone-climate penalty over South America and Africa by 2100

• DOI: 10.5194/acp-22-12331-2022
• 发表时间: 2022-09-21
• 期刊: ATMOSPHERIC CHEMISTRY AND PHYSICS
• 影响因子: 6.3
• 作者: Brown, Flossie;Folberth, Gerd A.;Verbeeck, Hans
• 通讯作者: Verbeeck, Hans