Recognition of Chromium Distribution Features in Different Urban Soils by Multilayer Perceptron.

The paper deals with application of Multilayer Perceptron (MLP) to the prediction of Chromium (Cr) distribution features in different soil. The distributions of the element content in urban soils are intersectional and multifactorial in nature. The local features of soil formation are necessary taking into account to forecast the chemical elements content at the unmonitored sites. The raw data of elements content in the topsoil are the results of chemical analysis of the soil sample, selected in three cities of the Yamalo-Nenets Autonomous Okrug - Noyabrsk, Tarko-Sale and Novy Urengoy. During the soil surveys, 486 soil specimens were taken from the residual zones. According to spatial distribution of total chromium concentration of the spots with high-level concentration were recognized in Tarko-Sale and Novy Urengoy. Mean total concentration of chromium in specimens of the spot subgroups is by an order of magnitude higher than in subgroups of urban background. The MLP network structure is selected during the computer simulation based on the minimization of the RMSE individually for each area. The better accuracy is for Noyabrsk and for Tarko-Sale. MLP is suitable for modeling both the normal and abnormal spatial distribution of pollutants. For the distribution without marked features, like Novy Urengoy area, MLP model detects enough high error. [ABSTRACT FROM AUTHOR]