Technogenic succession of the Luga River in the impact zone of OAO Phosphorit

Abstract

The impact of the mining and industrial enterprise JSC "Phosphorite" on the ecosystem of the Luga River has been studied. The most important ways of influence are established; its zone is defined. For quantitative assessment of multicomponent anthropogenic load on the aquatic environment the original quantitative indicator reflecting the multiplicity of exceeding the stability of biota was developed and applied. Anthropogenic changes in the main abiotic and biotic parameters of the environment have been taken into account and analyzed. According to the values of the "water pollution index" the water of the Luga River in the zone of impact is characterized as "polluted", the results of bioindication testify to an intensive eutrophication and tarification of the watercourse. The most significant and indicative were changes in macrozoobenthos, which in this regard was used as the main bio-indicator. As it turned out, in the zone of impact the stability of the ecosystem is significantly (in some parts of the zone - more than twice) exceeded. This level of technogenic load is close to critical, causing irreversible changes in the ecosystem. At the same time, the level of Phosphorit's impact on the hydro-ecosystem was still somewhat lower than expected, taking into account the specifics of fertilizer production technology and the scale of secondary waste accumulation. Taking into account the growth of fertilizer production against the background of approaching the level of impact to the critical one, it is necessary, at least, to halve the current technogenic load. Appropriate environmental protection measures should be developed and implemented immediately