Coal pollution mitigation Since air is mostly nitrogen, combustion of coal often leads to production of nitrogen oxides. Sulfur dioxide and nitrogen oxides are primary causes of acid rain. For many years--before greenhouse gasses were widely understood to be a threat-- it was thought that these by-products were the only drawback to using coal. These by-products are still a problem, but they have been greatly diminished in most advanced countries due to clean air regulations. It is possible to remove most of the sulfur dioxide (SO), nitrogen oxides (NO), and particulate matter (PM) emissions from the coal-burning process. For example, various techniques are
Lichens and nitrogen cycling and decrease the growth of the lichen. If the lichen cannot increase its photobiont growth, high nitrogen uptake may result in a higher concentration than it physiologically requires which will negatively affect the lichen and it's host plant as the other nutrients are too limiting. Lichen’s response to nutrient enrichment is both species-specific and dependent its environmental factors e.g. nutrient concentration, light availability and water supply. Lichen is nitrogen sensitive and change in nitrogen availability can affect its health greatly. Two main nitrogen stress factors for lichens are nitrogen deficiency and high nitrogen deposition. Both types of nitrogen stress result