The analysis of possible variants of hydroecosystems change at various types anthropogenous successions is lead. Dependences normalized well-being functions of water community from resulting level of the technogenic influence defined by parameter Y are established. The equation describing water communities reaction on that type of technogenic influence, which most typical for the large industrial enterprises (including – the enterprises of a mountain-metallurgical complex) is offered.
The paper reviews techniques to assess environmental threat of wastewaters from mining companies. It was proved that the only reliable approach to assessment of technogenic impact on biological systems is application of both biological and non-biological environmental parameters, and which is crucial with obligatory account for their interdependence. Ecological investigation of a section of the Luga River in the impact area of the «PG Fosforit Company», located in the Leningrad Region, was used as an example of environmental impact of a mining company on water ecosystems.
Methods for quantitative study, assessment, rationing and selection of measures for regulation of multifactorial anthropogenic impacts on ecosystems of freshwater reservoirs and watercourses have been developed. Reaction of biota to influence is estimated by a condition of macrozoobenthos as the most sensitive bioindicator, and the influence itself is estimated by the special indicator taking into account effect of interaction of factors. The regulation of multifactorial impact is based on identifying its maximum permissible level, which does not cause irreversible changes in macrozoobenthos. Regulation of the impact is aimed at reducing it to the maximum permissible combinations of interacting factors to achieve a safe level of their joint biotic effect.
Currently, various methods are used to assess anthropogenic changes in the environment, which have a number of drawbacks. A method for assessing anthropogenic impacts on watercourses that uses quantitative patterns of biota response to a multifactorial load is proposed. The main bioindicator of multicomponent impacts is macrozoobenthos. Quantitative effect of interaction of factors is accurately transferred by original isobolic model. The method allows to solve the following problems: to estimate precisely the state of biota, to single out the main limiting factors, to take into account their interaction correctly, as well as to forecast the general effect of impact reduction from the developed nature protection measures. The method has been tested in the study of various technogenic impacts on freshwater reservoirs in Russia.
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
A method for quantitative assessment of multifactor impacts on freshwater ecosystems has been developed. The method uses the general regularities of technogenic succession in reservoirs that we have established. At the same time, macrozoobenthos turned out to be the best indicator of the state of aquatic environment, biotic and anthropogenic changes in the ecosystem. Its parameters are recognized as the main ones for assessment of external load on reservoirs. The universal dimensionless parameter Y, which expresses the proportion of exceedance of community stability, serves as a measure of impact. This parameter is taken into account on the basis of the original isobolic model. For the first time it allows to adequately take into account the effect of interaction of limiting factors of any nature and in any quantity. This ensures high accuracy of the assessment. Maximum permissible levels of complex impacts are determined. A unified quantitative approach to rationing and regulation of multicomponent technogenic load on hydro-ecosystems is given.
The impact of the mining enterprise OAO Phosphorit on the ecosystem of the Luga River and its tributaries has been fully assessed. It turned out that a significant contribution to the total technogenic load of the hydro-ecosystem is made not only by wastewater discharge, but also by the transfer of pollutants into the atmosphere. A considerable increase in the impact of the enterprise on the Luga and its nearest tributaries, including those located upstream, has been recorded. Not only clear changes in various abiotic indicators of exceeding the maximum allowable concentrations of biogenic elements - mineral and organic phosphorus, nitrates, ammonium, fluoride ions, sulfate, combination of oil products, but also the main biotic parameters (structural and functional characteristics of microphytobenthos, phito- and zooplankton, zoobenthos, ichthyofauna) were established. In the area of influence of OAO Phosphorit, the overall level of anthropogenic impact on the hydro-ecosystem is 2-3 times higher than the stability of the ecosystem, which is significantly (40%) higher than the background indicator. According to research results, negative changes in the Luga ecosystem are still reversible at present. However, even a relatively small (30% or more) increase in anthropogenic load can lead to rapid and irreversible biotic degradation of rivers in the entire zone of influence of Phosphorit. This defines high requirements for the development and implementation of a system of environmental protection measures for Phosphorit, especially taking into account the volume of production growth.
