Defense and avoidance of ozone under global change

Environ Pollut. 2007 Jun;147(3):525-31. doi: 10.1016/j.envpol.2006.08.042. Epub 2006 Oct 19.


The level II approach of the critical loads concept adopted by the UNECE aims at a flux based evaluation and takes into account environmental factors governing stomatal conductance. These factors will probably be affected by global change. The flux concept predicts that a decrease in stomatal conductance would protect trees from air pollution effects by decreasing uptake. However, experimental evidence is inconclusive. Numerous results suggest that pollutants and factors subject to global change (drought, CO(2)) may interact and even exacerbate effects, probably because antioxidative defense systems are involved in both, defense against pollutant effects and protection from natural stress. An effective pollutant dose, which is weighted by physiological defense capacity, would better predict such effects. In this review paper we argue that the flux-based approach is imperfect, because global change effects may also modify the physiological susceptibility to ozone. Instead, a flux concept weighted by defense capacity should be tested.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Antioxidants / metabolism
  • Carbon Dioxide / analysis
  • Climate
  • Disasters
  • Environmental Exposure / adverse effects
  • Models, Biological
  • Oxidants, Photochemical / toxicity*
  • Ozone / toxicity*
  • Plant Physiological Phenomena / drug effects*
  • Plants / drug effects*
  • Reactive Oxygen Species / metabolism


  • Antioxidants
  • Oxidants, Photochemical
  • Reactive Oxygen Species
  • Carbon Dioxide
  • Ozone