Evaluating the Effects of Environmental Stress on Leaf Chlorophyll Content as an Index for Tree Health

Abstract

Chlorophyll content plays a vital role in photosynthetic and biomass production in all plants. Because chlorophyll shows a greater sensitivity to changes in external conditions than do other pigments in foliage, such as carotenoids for example, chlorophyll content in leaves may be a good surrogate for environmental stress, changes in temperature and humidity, as well as in pollutant levels both in the air and in the soil. This paper reviews the potential for chlorophyll content in the leaves of trees as a measure of tree health, resistance to stress and environmental conditions. Because chlorophyll content is shown to decrease dramatically with increases in pollution, non-destructive methods for evaluating the amount of chlorophyll in leaves and its changes over a time may be a sufficient indicator for environmental pollutant levels in the air, in the soil and in the water used by a tree.