Ecophysiological Responses of Plants to Air Pollution
Published Online: 15 FEB 2013
Copyright © 2001 John Wiley & Sons, Ltd. All rights reserved.
How to Cite
Caporn, S. J. 2013. Ecophysiological Responses of Plants to Air Pollution. eLS. .
- Published Online: 15 FEB 2013
In industrialised and heavily populated regions of the world, air pollution has an important influence on vegetation, affecting the production, abundance and distribution of plants. The principal primary pollutants are reactive compounds of sulphur, nitrogen and hydrocarbons emitted during the combustion of fossil fuels in industry, transport and from intensive farming. Increasing in importance is the secondary pollutant ozone. The direct effect of pollutants on plants is strongly influenced by the extent of their uptake into the plant tissues. Pollution also affects soils through increasing soil acidity and altering the balance of soil nutrients affecting roots and plant nutrition. Air pollution affects plants interactions with pests and pathogens and the sensitivity of vegetation to cold and drought stress. Understanding the ecophysiological responses and mechanisms by which air pollutants affect plants helps policymakers to set guidelines for air pollution to protect vegetation, crops and ecosystems.
Fossil fuel combustion and intensive agriculture are the main sources of air pollutants, which may be transported over long distances to affect plant life on a global scale.
In developed nations, sulphur dioxide, smoke and acid rain were the main acute air pollution concerns in the past, but now ozone and reactive nitrogen may pose the greatest threats.
Pollutants are deposited to plants as dry deposition of gases and particles and wet deposition in rain and cloudwater.
Stomata and cuticle on plant's surfaces provide an important control on uptake by vascular plants.
Bryophytes and lichens are vulnerable to air pollution as they lack a protective cuticle.
Acid rain, ozone, SO2 and other pollutants can directly injure the physiology of above ground plant tissues such as leaf gas exchange, carbon transport or flowering.
Soils are affected by increased acidity and nitrogen deposition which have long term effects on plant nutrient uptake, root system health and species competition.
Biodiversity and structure of plant communities appears to be damaged by long term nitrogen deposition.
Air pollution increases plant attack from pests and pathogens and increases vulnerability to cold and drought stress.
More understanding is needed of damage mechanisms to inform air quality guidelines to protect plants and their ecosystems.
- air pollutants;
- wet and dry deposition;
- plant uptake;
- plant physiology;