Ground-level ozone - a threat for biodiversity?

The concentrations of various compounds in the atmosphere such as tropospheric ozone have rapidly changed during the last century, and they continue to change. While it has been shown that ozone concentrations have significant adverse effects on crop yields, forest growth and species composition, the impacts of ozone on biodiversity are largely unknown. In particular, we know relatively little about how ozone affects ecosystems, including plant assemblages, faunal organisms, soil food webs, or interactions with other biotic or abiotic stresses. Understanding the impacts of ozone on ecosystem structure and functioning is especially relevant to assess the consequences of ozone exposure for the genetic diversity in agriculture, forestry, and semi-natural ecosystems. There is an urgent need to develop more holistic approaches linking the effects of ozone, secondary effects, and adaptation to predicted climate changes on sensitive individual "key" species, species interactions and ecosystem function.