Using Lichens As Indicators Of Air Quality Lichens are natures own bio-indicators of polluted or pure air. As bio-indicators, lichens respond in an especially clear way to a change in the environment. They are bio-indicators for air pollution since they derive their water and essential nutrients mainly from the atmosphere rather than from the soil. They also are able to react to air pollutants all year round. Compared with most physical/ chemical monitors, they are inexpensive to use in evaluating air pollution. Lichens can also be used to measure toxic elemental pollutants and radioactive metals because they bind these substances in their fungal threads where they concentrate them over time. Environmental scientists can evaluate this accumulation to determine the history of the local air. Different species of lichen thrive in areas with poor air quality. Other more sensitive lichens will only grow where the air is of high quality with few or no pollutants. Well, my Biology and research teacher at the Dumaguete City High School said that lichens are actually composed of two types of organisms living together, a fungus and an alga. The fungus makes the body that protects the alga and the alga provides the food for the fungus.It is not known whether the fungus that causes ‘tar spots on sycamore leaves is related to air pollution but it is hoped that by plotting them on maps with the bio-indicator lichens scientists can learn more about the mysterious blotches. Lichens have been used as bio-indicators of air quality. Their use as an air quality meter was first discovered when they disappeared from the trees after the Industrial Revolution that caused increased acidity in rain. Lichens are sensitive to nitrogen-containing pollutants, namely oxides of nitrogen and ammonia. These oxides are the result of burning fossil fuels, vehicle exhaust emissions and intensive agricultural practices including the use of fertilizers and pesticides. Oxides of nitrogen and ammonia have detrimental effects on both human health and the natural environment. No lichens still tells us something about the air quality in that area fscopal.files.wordpress/2010/02/chart-nitrogen-sensitive-tr.jpg
Posted on: Fri, 25 Apr 2014 17:24:09 +0000
Trending Topics
Recently Viewed Topics
© 2015