Population dynamics ofPotamothrix alatus paravanicusPoddubnaya & Pataridze (Tubificidae) in different areas of Lake Sevan

✍ Scribed by K. Jenderedjian

• Publisher: Springer
• Year: 1994
• Tongue: English
• Weight: 528 KB
• Volume: 278
• Category: Article
• ISSN: 1573-5141
• DOI: 10.1007/bf00142336

✦ Synopsis

Potamothrix alatus paravanicus Poddubnaya & Pataridze (Tubificidae) is the most abundant species of benthic invertebrate in Lake Sevan and the only species in the deep profundal. Differences in annual temperature, length of the stratification period (low oxygen content) and bottom sediment characteristics influence the population of P. a. paravanicus in different depth zones of Lake Sevan. From shallow to deep water a regular increase of the following indices was observed in 1984-1987: annual biomass from 1.2-2.0 to 8.2-17.0 g m-* wet weight; mean individual wet weight of clitellate specimens from 2.0-3.8 to 8.3-16.6 mg; total life span from one and a half to more than 20 years; the length of breeding season from 2-3 to 12 months.

An important ecological distinction between P. a. paravanicus and allied Potamothrix hammoniensis (Michaelsen) is the much lower fecundity of the former species.