On the spatial distribution of gammarids (Crustacea, Amphipoda) in the Selenga region of lake Baikal (Siberia, Russia)
Martin, P.; Kamaltinov, R.M.; Martens, K.; Goddeeris, B. (1993). On the spatial distribution of gammarids (Crustacea, Amphipoda) in the Selenga region of lake Baikal (Siberia, Russia). Belg. J. Zool. 123(Suppl. 1): 50 In: Belgian Journal of Zoology. Koninklijke Belgische Vereniging voor Dierkunde = Société royale zoologique de Belgique: Gent. ISSN 0777-6276; e-ISSN 2295-0451, more | |
Keywords | Distribution > Geographical distribution Amphipoda [WoRMS]; Crustacea [WoRMS]; Gammaridae Latreille, 1802 [WoRMS] PNE, Russia, Siberia Brackish water |
Authors | | Top | - Martin, P., more
- Kamaltinov, R.M.
- Martens, K., more
- Goddeeris, B., more
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Abstract | The Selenga region of Lake Baikal constitutes a delta between the central and southern basins of the lake and contains large amounts of suspended material transported by the Selenga river. Four transects were sampled on soft sediment during the August 1991 expedition of the RN 'Vereschagin' in the surroundings of the delta (south, north, opposite, Murinsk bank). The vertical and bathymetric distributions of gammarids (a.o. biological groups) were studied, the former in correlation with measurements of oxygen penetration depths in the sediment. An exponential decrease between density of gammarids and sediment depth was observed. A significant positive correlation was noted between the maximum sediment depth at which gammarids were present and the depth of oxygen penetration in the sediment as well as the thickness of the oxidized layer. Ninety-six percents of gammarids were present in the upper three cm (which corresponds to the oxidized layer) although some species were able to penetrate as deep as seven cm. By far the highest densities were found in the upper 25Om of the lake, i.e. the water volume which mixes twice a year .The near total absence of gammarids in our abyssal samples is probably due to a strong decrease in density with increasing bathymetric depth and possibly also a patchy distribution of these organisms. |
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