Abundance and seasonal variation of benthic macroinvertebrates in an ox-bow lake in West Bengal, India.

摘要

Benthic macroinvertebrates were studied from the ox-bow lake Sindrani in the district of North 24-Parganas in West Bengal, India. The total zoobenthos ranged from 42 to 1043 individuals/m² with an average of 283 individuals/m². Zoobenthos were highest (average of 425 individuals/m²) in monsoon followed by post-monsoon (average 210 individuals/m²) and pre-monsoon (average 179 individuals/m²). In monsoon, oligochaetes dominated with 58.28% followed by gastropods (30.74%) and dipterans (10.43%). In pre-monsoon and post-monsoon, dominance followed the order: Gastropoda>Diptera>Oligochaeta. Dominance of oligochaetes in monsoon was possibly due to heavy jute retting in this wetland. Gastropoda was represented by 11 genera followed by Diptera (5), Oligochaeta (2) and Odonata (1).