Zooplankton diversity and physico-chemical conditions of two wetlands of Jalpaiguri District, India.

ABSTRACT

Zooplankton diversity and physico-chemical parameters of two wetlands were studied to adjudge the health and potential threats of those wetlands. Zoolankton species diversity in both the wetlands was found to be quite high. Rotifer was the richest group having 48 species and Brachionus species (11) enjoy numerical superiority followed by Lecane (9). Only during premonsoon period rotifer and cladoceran diversity was significantly different in these two wetlands. Presence of higher number of copepods in all seasons signifies oligotrophic condition of these wetlands. Physico-chemical parameters indicate prevalence of good quality of water in both the wetlands but the wetland (Domohani Beel) having lesser zooplankton diversity experienced deterioration in water quality during premonsoon season. During premonsoon period Domohani wetland experienced intense ‘Boro’ cultivation having little water covered area with full of water hyacinth; and this poor condition reflects on its poor zooplankton diversity. Zooplankton diversity was significantly positively correlated with TSS, vegetative heterogeneity, and submerged macrophytes and negatively correlated with BOD and free CO2 of water. Loss of natural vegetation and eutrophic condition borne out of agricultural practices are thus hampering zooplankton life having an adverse effect on food chain.