Abstract—

The development of principles and methods for restoring ecological systems that have undergone intense anthropogenic impacts is one of the most important tasks of modern ecology. This work is devoted to studying the regularities of the influence of organic pollution on the structure and functional characteristics of zoobenthic communities and the degree of restoration of the pristine communities of bottom animals and the quality of the waters of the small Izhora River by bioindication characteristics. For this, the results of studies from the 1970s and 2000s were compared. Intensive organic-matter pollution influenced the structure and functioning of zoobenthos, increasing biomass and energy flow through the bottom animal communities. At the same time, the role of oligochaeta worms in the bottom communities sharply increased, the role of larvae of amphibiotic insects decreased, the species richness and biological diversity of zoobenthos declined, and the efficiency of energy transfer between trophic levels of primary and secondary consumers fell. Water quality in accordance with the values of the integrated index IPʹ corresponded to the fifth highest class of pollution (dirty). Downstream, due to self-purification processes, the water quality and ecosystem state improved slightly, but this improvement was not very significant, which indicated that the river ecosystem was not able to process excess organic matter entering the river. The introduction of wastewater treatment from organic pollutants at sewage treatment plants contributed to the restoration of the structural and functional organization of zoobenthic communities and significantly improved the state of the river ecosystem. However, a complete restoration of water quality did not occur: it improved to moderately polluted.

中文翻译：

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有机污染水平降低后河流生态系统中底栖动物群落的恢复和水质

摘要-

恢复受到强烈的人为影响的生态系统的原理和方法的发展是现代生态学的最重要任务之一。这项工作致力于通过生物指示特性研究有机污染对游动底栖动物群落结构和功能特性的影响规律，底层动物原始群落的恢复程度以及小伊佐拉河水质。为此，比较了1970年代和2000年代的研究结果。严重的有机物污染影响了底栖动物的结构和功能，增加了通过底层动物群落的生物量和能量流。同时，低聚蠕虫在底层社区的作用急剧增加，两栖昆虫的幼虫的作用降低，游动底栖动物的物种丰富度和生物多样性下降，营养一级和次级消费者的营养水平之间的能量转移效率下降。按照综合指数IPʹ的值，水质相当于污染的第五高等级（脏污）。下游，由于自净过程，水质和生态系统状态略有改善，但改善不是很明显，这表明河流生态系统无法处理进入河流的过量有机物。污水处理厂从有机污染物中引入废水处理，有助于恢复底栖动物群落的结构和功能组织，并显着改善了河流生态系统的状况。但是，水质并未得到完全恢复：它已改善至中度污染。