Non-Parametric Analysis of Nitrogen Trends in the form of Nitrate and Nitrite in Rivers and Streams of the Contiguous United States for 1990-2019

• DOI: 10.20944/preprints202106.0171.v1
• Publication Date: 2021-06-08T07:35:22Z
• Authors: Amin Mohebbi; Simin Akbariyeh
• Keywords: Nitrogen balance; Reactive nitrogen; Nutrient pollution

Nitrogen and phosphorous support the ecosystem by supplying nutrients to algae aquatic plants. Having them in excess results eutrophication of waters creating quality problems. In past, nitrogen has been widely investigated for wells context groundwater flow. However, a national-scale assessment rivers streams not received enough attention. this research, Wilcoxon rank sum test, as non-parametric hypothesis testing method, applied concentration form nitrate-nitrogen nitrite-nitrogen Contiguous United States. This approach was particularly selected because non-normal positively skewed levels occurring surface method able identify impaired body well quantify confidence, significance, errors involved. The Northern Appalachians (NAP), Plains (NPL), Xeric (XER) ecoregions were worsening nitrogen-nitrate condition with NAP, XER needed immediate actions. did pose an threat, so mitigation plans should focus more on remediation. It shown that superior two-sample t-test yielding lower type II errors.