ИСТИНА

Environmental pollution by persistent toxic compounds is a priority geoecological and environmental-geochemical problem. PAHs are intensively studied priority ecotoxicants, because of their high toxicity, carcinogenic mutagenic effects, and also relative stability in the environment. The most important feature of PAHs is the ability to “label” natural and anthropogenic processes. This allows you to establish the source of pollution, its properties, track the dynamics of the processes of accumulation and migration of environmental pollution. In the world practice of environmental monitoring, the list of 16 priority PAHs formed by the US EPA has become most widespread. An analysis of the thermodynamic characteristics of the behavior of these substances allowed us to identify the features of soil pollution on the campus of RUDN University. The paper estimates the spatial distribution of the entropy of the PAH association on the territory of RUDN-University. The territory located in a relatively prosperous area of Moscow is subject to significant traffic impacts. In this regard, the state of soils is seriously changed in comparison with the background territories. Our estimates are based on determining the intensity of pollution processes and the processes of PAH migration from transport objects by the molecular entropy indicator of PAH associations. This is a fundamentally new approach in geochemical estimates. It allows you to take into account the saturation of soils with pollutants and evaluate the activity of geochemical flows. The regularities of the spatial distribution of entropy of the soil polluting PAHS association for the considered local territory are obtained. The dynamics of activity of the processes of migration and accumulation of PAHs as markers of total pollution was revealed. Analysis of PAH indicator ratios confirmed that their main source in soils is motor vehicle emissions on roads and in the parking area. The zones of entropy minima and maxima of PAHs associations in soils were identified, the formation of which is due to a combination of transport activity, as well as soil self-cleaning processes (including natural phytoremediation). At the same time, the activity of soil self-cleaning processes in terms of changes in entropy varies in different zones of the campus due to the total anthropogenic load and a decrease in the assimilating capacity of soils.