Ozone pollution may limit the benefits of irrigation to wheat productivity in India

作者：Gabriella Everett, Øivind Hodnebrog, Madhoolika Agrawal, Durgesh Singh Yadav, Connie O’Neill, Chubamenla Jamir, Joanne Cook, Pritha Pande, Sam Bland, Lisa Emberson · 发表于：Biogeosciences · 年份：2025 · DOI：10.5194/bg-22-4203-2025 · 被引用次数：5 · 研究领域：Plant responses to elevated CO2、Atmospheric chemistry and aerosols、Air Quality and Health Impacts

Abstract. Ground-level ozone (O3) pollution and heat and water stress are recognised as key abiotic stresses which threaten the ability of wheat yields to meet the growing demand for food production in India. The magnitude and interplay of O3 and water stress effects are tightly coupled via stomatal conductance and the transpiration pathway. Existing modelling methods that assess the stress response as a function of O3 and water vapour stomatal flux are applied to assess O3's role in limiting the productivity afforded by irrigation. We investigate the effect of these stresses on the grain yield of older (HUW-234) vs. recently released (HD-3118) Indian wheat cultivars under recent-past and future climates and O3 precursor emission profiles (using RCP4.5 and RCP8.5 scenarios). Water stress in rainfed conditions was modelled to analyse the trade-off between O3-induced vs. water-stress-induced yield loss to quantify the extent to which water stress mitigates O3 stress via reduced stomatal conductance. Under rainfed conditions for the years 1996–2005, the mean water-stress-induced and O3-induced yield losses for HUW-234 were 13.3 % and 0.6 %, respectively. The latter was a significant decrease from the mean O3-induced yield loss of 10.6 % modelled under irrigated conditions (i.e. no water stress). Similarly, under the RCP4.5 and RCP8.5 scenarios for the mid-century, water-stress-induced yield losses under rainfed conditions were 10.1 % and 20.0 %, while mean O3-induced yield losse...