Molluscan fauna of the lower reaches of the Syoyakha River (Yamal Peninsula)

Abstract

The molluscan fauna of the Syoyakha (Zelenaya) River remain poorly explored even though the Syoyakha is one of the biggest rivers on the Yamal Peninsula. The Syoyakha River is remarkable for its high fish stocking capacity and it plays an important role in the seasonal distribution and migration of commercial fish species. Freshwater mollusks are known to be a major component of freshwater ecosystems and they make up a part of the diet of many commercially important fish species. The species composition of the mollusks inhabiting the lower reaches of the Syoyakha River has been studied. Five bivalve species of the family Sphaeriidae were found, namely Sphaerium corneum (Linnaeus, 1758), Pisidium casertanum (Poli, 1791), P. globulare (Clessin in Westerlund, 1873), P. lilljeborgi (Clessin in Esmark et Hoyer, 1886) and P. dilatatum (Westerlund, 1897). In general, the molluscan fauna of the lower reaches of the Syoyakha River are taxonomically poor, which can be considered typical of freshwater invertebrate communities living at high latitudes. Another reason for the decline in species diversity may lie in the absence of any large transit watercourse in the basin in question allowing northward dispersion of the mollusks. The average density of mollusks in the watercourse stretch under study varied from 98.9 ind./m 2 to 620.5 ind./m 2 . P. globulare settlements had the highest recorded density of 1,442.9 ind./m 2 . The mollusks are confined to clayey, silty and sandy substrates with remnants of vegetation. The fauna is basically formed by widespread Palearctic and Holarctic mollusk species that have adapted to the extreme conditions of the Arctic. The findings may be used for hydrobiological and fishery characterization of the watercourse given that the recorded species of S. corneum, P. globulare, P. lilljeborgi, and P. dilatatum are a major food item for important fish species, such as cisco, vendace, char, muksun, etc.

Mobilization of Geochemical Elements to Surface Water in the Active Layer of Permafrost in the Russian Arctic

“…This part of the lowland comprises very flat watersheds of the Syoyakha and Murtyyakha Rivers and is covered with frozen bogs and palsas. The Syoyakha is one of the largest rivers of the Yamal Peninsula (Bespalaya et al, 2018); its watercourse is 165 km long and its watershed covers an area of 4,400 km 2 (Bespalaya et al, 2018). The Murtyyakha River has roughly 580 watercourses and numerous lakes in its basin, which contains 70 rivers greater than 10 km in length.…”

Freshwater gastropods of the western part of the Kola Peninsula and northern Karelia (northern Europe)

“…Based on slight differences in shell morphology, some authors recognized a series of species closely related to Ampullaceana balthica s. str. [Kruglov, Starobogatov, 1983;Stadnichenko, 2004;Starobogatov et al, 2004;Kruglov, 2005], but the validity of many of them lacks the molecular and/or morphological support [Schniebs et al, 2011;Bolotov et al, 2017;Aksenova et al, 2018].…”

“…According to the current knowledge, Peregriana peregra can be distinguished from Ampullaceana spp. only with the use of molecular characters [Aksenova et al, 2018].…”

“…Freshwater molluscs of the Arctic and subarctic parts of Eurasia had been studied for more than a century, and these studies have been especially intensified during the last decades [Frolov, 2010;Bespalaya, 2014;Bespalaya et al, 2015aBespalaya et al, , 2015bBespalaya et al, , 2018Nekhaev, 2015;Ovchankova et al, 2015;Vinarski et al, 2013bVinarski et al, , 2020. On a date, species composition has been described for many regions of the European Far North, including northeastern Europe [Leshko, 1998;Bespalaya et al, 2011Bespalaya et al, , 2017, Scandinavia [Esmark, Hoyer, 1886;Westerlund, 1897;Økland, 1990], and some islands [Smith, 1896;Mandahl-Barth, 1938;Bespalaya et al, 2009Bespalaya et al, , 2015a.…”

Observing Mollusca Benthic Diversity to Measure the Success of the Implementation of Mulung Culture as an Effort to Conserve Aquatics in the Waters of Lapang-Batang Island, Alor Regency, East Nusa Tenggara.

“…Coral Reef ecosystems need time to recover when exposed to external disturbances that cause health problems. There are 2 (two) components in resilience, namely: (a) The ability to absorb or withstand the impact of pressure or stress (resistance); and (b) The ability to recover (recovery), [12].…”