Geoecological Aspects of Collecting Fossil Remains of Mammoth Fauna

Harsh environmental conditions of the study area result in low rates of ecosystem renewal. Results of geoecological studies at the sites of searching for and extraction of fossil remains of mammoth fauna in the middle reaches of the Indigirka River are presented. During the extraction of mammoth fauna remains using hydraulic washing-out, landscape components are disrupted, followed by leaching of the bedrock into creeks and rivers, thus leading to deterioration of abiotic components of the aquatic environment. Analysis of the geoecological state of the abiotic components of the ecosystem at the study site was used to assess the effects of the extraction of mammoth tusks by hydraulic mining. The study objects are cryogenic soils, bottom sediments and surface waters of the Semyuelyakh, Tirekhtyakh, and Indigirka rivers on the middle course segment. Soil and sediment samples were used to determine pH, mobile phosphorus, and C org . Total content of Cu, Sn, Zn, Pb, Ge, B, Cr, Ni, V, Sc, Co, Ba, Sr, Nb, Zr, Y, Yb was analyzed using the spectral semi-quantitative method. The cationic-anionic composition, mineralization, suspended solids, pH and concentrations of Mn, Pb, Ni, Cu, Cd, Zn, Co, Fe were determined in surface water samples by atomic absorption spectrometry with electrothermal atomization. The concentration coefficients and anthropogenic load index were calculated. Studies conducted in 2022 established that there was a local impact on surface water. At the site of hydraulic pumping of water used to wash away the soil, an increase in mineralization, suspended solids, color index, and changes in the trace element composition were recorded, showing that manganese, nickel, iron, copper and zinc contribute the most to water pollution levels.