Environmental factors influence on leeches distribution in the middle reaches of the Irtysh River

Abstract

The Irtysh River is a transboundary watercourse that exhibits a wide range of climatic conditions, environments and ecological niches. As a result of the technogenic impact of industrial enterprises on surface and underground waters all the main tributaries of the middle reaches of the river Irtysh are in different degrees of pollution. Due to the impact of sewage and other wastes from the mining and metallurgical industry, in the waters of the river basin Irtysh the concentration excess of a number of toxic metals is observed. Among the invertebrates used to assess the state of natural waters, representatives of the Annelida type are often used. Since annelids are among the most common organisms on Earth, this makes it possible to study them in many regions and to assess the specificity of the impact and compare the impact of various pollutants in similar natural and climatic zones. It is known that the distribution of freshwater leeches is largely determined by natural and climatic conditions, landscape characteristics and the specifics of trophic connections, etc. In this case, the most important parameters are the physicochemical properties of water. This paper provides information on the factors influencing the species composition and structural indicators of leech communities living in the middle reaches of the Irtysh River.

First data on the Hirudinea fauna of lotic ecosystems of the Khanty-Mansi Autonomous Area (Russia)

“…Non-parasitic representatives of this group are a source of nutrient-valuable substances, and are, therefore, attractive to predatory mammals, semi-aquatic birds, fishes, and amphibians ( Lukin 1976 ). In addition to their role in the food web, leeches are of interest as accumulators of toxicants ( Lapkina and Flerov 1980 ; Romanova and Klimina 2009 ) and as bioindicators of water pollution ( Bezmaternykh 2007 ; Martins et al 2008 ; Fedorova 2020 ). The ecological role of parasitic forms is not limited to regulating the number of host species by weakening and creating conditions for the development of infections.…”