How does pollution affect plants?
One type of pollution which affects plants and therefore plant diversity is air pollution. This not only adds to global warming which increases temperatures (effect on plants stated above) but is also damaging to the vegetation itself. Although there are many pollutants, some of the most prominent are sulfur dioxide(〖SO〗_2) and ozone(O_3). There are various effects caused by the damaging pollution, some of which are premature leaf dropping, stunted growth and twig dieback.
Other types of pollution affecting plant growth are water and soil pollution; these can have both positive and negative effects. Fertilizers may leach into water sources from surrounding soil, increasing their nitrogen (N), phosphorus (P) and potassium (K) contents. These nutrients encourage plant growth; however, in areas with stagnant bodies of water, algae growth can cause oxygen deprivation to plant and animal life below the algal bloom. Acid rain can cause a decrease in water pH in the soil which may be out with plants growing range. Extremely acidic or basic pHs could kill plants, leading to a decrease in diversity. Phytotoxicity may also occur which causes dead spots on leaves, dying seedlings, and poor growth. This is caused by root uptake of chemicals which are toxic to plants, so, therefore, poison them.
Line transects are commonly used to measure the coverage of plants in an area. When used with systematic sampling, samples can be taken at set points along a transect by placing a closed quadrate at the desired section and determining the percentage coverage of each species present. Using this data, diversity can be calculated from Simpsons Diversity Index which takes into account both richness and evenness; it will produce a result between 0 and 1, the higher the resulting number, the higher the species diversity. The calculation for this is:
Spearman’s Ranking can then be calculated to test the strength of correlation between two points (in this case distance along transect and species diversity).