Preliminary assessment of risk of ozone impacts to maize (Zea mays) in southern Africa
CSIR Environmentek, PO Box 17001, Congella 4013, Durban, South Africa; Stockholm Environment Institute at York, University of York, Box 373, York, T01 5YW, United Kingdom; Sasol Synfuels, Private Bag X1000, Secunda 2302, South Africa; Climatology Research Group, University of the Witwatersrand, Private Bag X3, WITS 2050, South Africa
Surface ozone concentrations in southern Africa exceed air quality guidelines set to protect agricultural crops. This paper addresses a knowledge gap by performing a preliminary assessment of potential ozone impacts on vegetation in southern African. Maize (Zea mays L.) is the receptor of interest in the main maize producing countries, i.e. South Africa, Zambia and Zimbabwe. Surface ozone concentrations are estimated for the growing season (October to April) using photochemical modelling. Hourly mean modelled ozone concentrations ranged between 19.7 and 31.2 ppb, while maximums range between 28.9 and 61.9 ppb, and are near 30 ppb over South Africa and Zambia, while in Zimbabwe, they exceed 40 ppb and translate into monthly AOT40 values of over 3000 ppb h in five of the seven months of the growing season. This study suggests that surface ozone may pose a threat to agricultural production in southern African, particularly in Zimbabwe. © 2005 Elsevier Ltd. All rights reserved.
Agricultural products; Air quality; Ozone; Space surveillance; Vegetation; AOT40; Crop loss; Ground level ozone; Maize; Southern Africa; Air pollution; ozone; air quality; maize; ozone; air pollutant; air quality; article; chemical model; crop production; environmental impact; environmental monitoring; maize; nonhuman; ozone layer; photochemistry; plant growth; risk assessment; seasonal variation; South Africa; vegetation; Zambia; Zimbabwe; Circadian Rhythm; Environmental Monitoring; Models, Chemical; Oxidants, Photochemical; Ozone; Risk Assessment; Seasons; South Africa; Zambia; Zea mays; Zimbabwe; Ozone; Plants; Africa; Southern Africa; Sub-Saharan Africa; Zea mays