Impacts of air pollution on productivity of natural and cultivated tropical C4 grasses: implications in the face of land use change in Brazil

空气污染对天然和栽培热带 C4 草生产力的影响：巴西土地利用变化的影响

• 批准号: NE/V008498/1
• 负责人: Stephen Sitch
• 金额: $ 10.31万
• 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: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FV008498%2F1
• 关键词: Impacts; air; pollution; productivity; natural

In the lower atmosphere ozone (O3) is an important anthropogenic greenhouse gas and is an air pollutant responsible for several billion pounds 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. Tropical ecosystems 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. Alongside this growing population, we see the expansion of O3 precursor emissions from urbanization and high-intensity agricultural areas. Sugarcane is an important tropical and bioenergy crop, supplying raw material for sugar, ethanol (biofuel) and energy production and contributes to the bioeconomy of both São Paulo state (SP) and Brazil. While the São Paulo state is responsible for over half of Brazilian sugarcane production, sugarcane-derived products account for 17% of the Brazilian energy matrix. In a global context, biofuel production is one major land-based carbon-neutral approach to reduce our reliance on fossil fuels, and thus help society to achieve the challenging Paris accord of limiting climate change to below 2oC.Over the two last decades, SP state has experienced large-scale conversion of pasture (natural C4 grass) to sugarcane fields. At the same time air quality measurements demonstrate O3 concentrations across much of SP above those known to be harmful to plants.This project will make the first comprehensive set of measurements of O3 effects on plant functioning and growth in tropical grasses, both cultivated (e.g. sugarcane) and natural (e.g. used as pasture) using our unique tropical experimental facility in Cairns, Australia. Here we expose tropical grasses to different levels of ozone, to derive relationships between O3 dose and productivity loss. In addition, we investigate the role of drought on the O3 sensitivity of tropical grasses.Finally, we will use this information to assess the impact of regional O3 concentrations and changing land-cover (from natural C4 pasture to sugarcane) for southern Brazil and engage with relevant stakeholders from both policy and academia.

在低层大气中，臭氧 (O3) 是一种重要的人为温室气体，也是一种空气污染物，自 1850 年以来，由于车辆、工业过程和燃烧的化学排放，地表 O3 已增加一倍，每年造成数十亿磅的植物生产力损失。热带生态系统占全球植物生产力的近一半，在这些热带地区，我们可能会看到本世纪人口的最大扩张，同时我们也看到臭氧前体排放量的增加。城市化甘蔗是一种重要的热带和生物能源作物，为糖、乙醇（生物燃料）和能源生产提供原材料，为圣保罗州（SP）和巴西的生物经济做出了贡献。巴西甘蔗产量占一半以上，甘蔗衍生产品占巴西能源矩阵的 17% 在全球范围内，生物燃料生产是一种主要的陆基碳中和方法。减少我们对化石燃料的依赖，从而帮助社会实现将气候变化限制在 2oC 以下的具有挑战性的《巴黎协定》。在过去的二十年里，SP 州经历了大规模的牧场（天然 C4 草）向甘蔗田的转变与此同时，空气质量测量表明，SP 大部分地区的 O3 浓度高于已知对植物有害的浓度。该项目将首次全面测量 O3 对热带草类植物功能和生长的影响，无论是栽培的（例如草本植物）还是草本植物。在这里，我们将热带草暴露于不同水平的臭氧中，以得出 O3 剂量与生产力损失之间的关系。干旱对热带草的 O3 敏感性的影响。最后，我们将利用这些信息来评估巴西南部区域 O3 浓度和土地覆盖变化（从天然 C4 牧场到甘蔗）的影响，并与这两项政策的相关利益相关者进行接触和学术界。

项目成果

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

到 2100 年南美洲和非洲的臭氧气候损失

• DOI: http://dx.10.5194/acp-22-12331-2022
• 发表时间: 2022
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: Brown F

Impacts of ground-level ozone on sugarcane production.

地面臭氧对甘蔗生产的影响。

• DOI: http://dx.10.1016/j.scitotenv.2023.166817
• 发表时间: 2023
• 期刊: The Science of the total environment
• 作者: Cheesman AW