US EPA

35322 

Book/Book Chapter 

Modification of plant response by environmental conditions 

Mills, G 

2002 

John Wiley & Sons 

Chichester, United Kingdom 

Air pollution and plant life 

343-358 

is a chapter of 035259 Air pollution and plant life

The growth, development and reproductive potential of a plant are closely coupled to the environmental conditions in which it lives. Where one or more of the essential conditions for growth (light, water, nutrients etc.) are in short supply or in excess, the plant may exhibit a 'stress' response such as anthocyanin pigmentation of the leaves, reduced growth, or leaf and/or fruit abscission. Whether the plant is adversely affected by stress or healthy, the conditions in which it lives will influence both the uptake (flux) of a gaseous pollutant via the stomata and the ability of the plant to detoxify the pollutant and repair any damage it has induced. For example, some environmental conditions cause stomatal closure and effectively protect the plant against pollutant damage. whilst in other conditions, the closing mechanism of the guard cells is damaged, leading to increased pollutant uptake and consequent effect. By studying the modifying influence of the environment on plant responses to pollutants it becomes possible to predict how plants will respond in the cocktail of environmental conditions associated with the open field. Such information is of particular relevance for evaluation of the impacts of global climate change and for the modelling of pollutant effects across continents. To provide a comprehensive review of all of the literature on the effects of environmental conditions on the separate responses of trees, crops, natural vegetation and lower plants, to all of the major pollutants would require far more space than is available here. In the first part of this chapter the influences of the most important climatic and soil factors on the responses to the gaseous pollutants O3, NOx, NH3 and SO2 are discussed. For each factor, the pollutant and vegetation groups that are of greatest relevance are considered in the most detail. Later in the chapter, the ways in which multiple co-occurring factors influence responses to pollutants are examined using the increased sensitivity of plants to SO2 during the winter as an example. 

2nd 

Bell, JNB; Treshow, M