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Scientific writing assignment 7!

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Many ecosystems need a source of nitrogen. Nitrogen comes naturally from sources in the environment like volcanoes, forest fires, lightening etc. Nitrogen has some negative effects on the environment as well, consisting of eutrophication of ecosystems and acidification of ecosystems, which may lead to a change in the plant diversity. In Europe, the nitrogen emissions are controlled and regulated by union directives. In 1990 the European moss biomonitoring network was brought to life. They determine patterns of the heavy metal decomposition in the atmosphere. They use mosses to determine the measurement of heavy metals in the atmosphere. This is possible since mosses are very absorbent to anything, thus allowing metals to be absorbed from the air. The mosses provide a complementary data base for researchers. The last moss survey that was conduction was in 2005/2006 for the first time in
16 centuries (H. Harmens et al., 2011).!

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The results of the tests for heavy metals in the atmosphere were observed. The lowest concentration of nitrogen in the atmosphere was found to be in northern Finland as well as northern parts of the UK. High nitrogen concentrations were found in the Midlands and the
South-East. Belgium, Germany, France, Slovakia, Bulgaria and Slovenia had the highest concentration of nitrogen in the atmosphere. The highest nitrogen deposit that was measure in this study was 15 kg ha-1y-1. There are some factors that may have affected this study, two being the uncertainty of modelled atmospheric nitrogen decomposition and the direct uptake of nitrogen from the soil the mosses are in. Since this was a general moss study, specific species weren’t taken into account and therefore the results may not be as accurate as thought to be.
Nitrogen decomposition increases as altitude increases due to the increased precipitation with a high altitude. To use mosses for testing the nitrogen concentration in the atmosphere accurately the effects of mosses with their ecosystems must be established first (H. Harmens et al., 2011). !

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Mosses can help