Ecological risk assessment attributed to rice and maize yield reduction due to long-term ground-level O3 impacts: A case study in Tay Ninh, Vietnam
The agricultural sector of Tay Ninh province accounts for about 28% of the province’s economic structure with agricultural land areas of 269,250 ha, contributing to 66.7%; particularly, cultivation accounts for 80% of the agricultural economic structure value. Sustainable agricultural development is an urgent mission as the local agricultural sector plays a quite important role in the local economy. Currently, tropospheric O3 has been evaluated as an air pollutant, causing crop yield reduction and significant economic damage. This study had built a methodological framework based on the application of the coupled Weather Research and Forecasting (WRF)/ Community Multiscale Air Quality Modeling System (CMAQ) model to assess the status of ground-level O3 concentration allocation in Tay Ninh province, Vietnam with typical cases of crop seasons (spring paddy and maize) in 2018, combined with existing exposure-response functions to quantify agro-economic losses. With the simulated 8-hour mean surface O3 concentration (daytime) ranging from 10.9 to 113.5 μg/m3, the economic impacts on rice (the spring season) and maize production were determined to reach more than 184 billion VND, contributing to roughly 0.18% in the total Gross Regional Domestic Product (GRDP) of Tay Ninh province in 2018. Moreover, this is also considered a baseline study to serve as a basis for extensive assessments and propose O3 precursor emissions control measures shortly.