Impact of air pollutants on plant populations

Abstract

Only recently have the potential lingering, insidious decline of whole forests and alterations of entire agronomic and natural plant populations imposed by air pollutants received recognition. Pathogenic air pollutants in many geographic areas of the world already impose a greater economic hazard to agriculture than do climatic or insect pathogens. The treatment of air pollutants to watershed species may be particularly great in the arid areas of the west where man's survival depends on a sustained water supply, which in turn is dependent on a healthy watershed cover. Plants have evolved, and plant communities have become stabilized, by selective pressures of the environment. When a new pressure is imposed, the plants malfunction and whole communities may be altered adversely; even a slight pressure or disturbance can upset the delicate balance of the ecosystem. Disturbances from air pollutants may be considerable. Much information is available regarding the general sensitivity of agronomic and major forest species to air pollutants; far less is known about the sensitivity or response of noncrop species and plant communities. Studies concerning the total threat of air pollutants to the environment should be accelerated immediately. 40 references.