Nutrient scaling for assessing eutrophication: The development of a simulated normal distribution

A statistical methodology based on probabilistic procedures is proposed for assessing eutrophication. A simulated normal distribution was developed fo r nitrate concentrations, based on the information derived from two data se ts. The first one is characteristic of oligotrophic conditions, and the sec ond of eutrophic conditions. The distribution parameters were calculated fr om the raw data without distorting their information by applying transforma tions or any other drastic data manipulation. A standard normal distributio n was derived and was evaluated in a case study. The proposed distribution can be used to define eutrophication scales, assign critical values, and te st any nitrate concentration data for the evaluation of the trophic conditi ons of the area in which they were collected.