title: Impact of multispecies diatom bloom on plankton community structure in Sundarban mangrove wetland, India.
abstract: A multispecies bloom caused by the centric diatoms, viz. Coscinodiscus radiatus, Chaetoceros lorenzianus and the pennate diatom Thalassiothrix frauenfeldii was investigated in the context of its impact on phytoplankton and microzooplankton (the loricate ciliate tintinnids) in the coastal regions of Sagar Island, the western part of Sundarban mangrove wetland, India. Both number (15-18 species) and cell densities (12.3 × 10(3)cellsl(-1) to 11.4 × 10(5)cellsl(-1)) of phytoplankton species increased during peak bloom phase, exhibiting moderately high species diversity (H'=2.86), richness (R'=6.38) and evenness (E'=0.80). The diatom bloom, which existed for a week, had a negative impact on the tintinnid community in terms of drastic changes in species diversity index (1.09-0.004) and population density (582.5 × 10(3) to 50 × 10(3)indm(-3)). The bloom is suggested to have been driven by the aquaculture activities and river effluents resulting high nutrient concentrations in this region. An attempt has been made to correlate the satellite remote sensing-derived information to the bloom conditions. MODIS-Aqua derived chlorophyll maps have been interpreted.
authors: Department of Marine Science, University of Calcutta, Calcutta, India.
authors: Sejuti Naha
authors: SN
authors: Biswas
authors: Department of Marine Science, University of Calcutta, Calcutta, India.
authors: Dibyendu
authors: D
authors: Rakshit
authors: Department of Marine Science, University of Calcutta, Calcutta, India. Electronic address: cusarkar@gmail.com.
authors: Santosh Kumar
authors: SK
authors: Sarkar
authors: Marine Biology Division, Marine, Geo and Planetary Sciences Group, Space Applications Centre (ISRO), Ahmedabad, India.
authors: Ranjit Kumar
authors: RK
authors: Sarangi
authors: Environment and Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, Tamil Nadu, India.
authors: Kamala Kanta
authors: KK
authors: Satpathy
mesh_terms: D000818:Animals; D044822:Biodiversity; D057919:Biological Oxygen Demand Analysis; D002734:Chlorophyll / Q000737:chemistry; D000077194:Chlorophyll A; D017377:Diatoms / Q000502:physiology*; D005843:Geography; D007194:India; D010839:Phytoplankton / Q000502:physiology*; D045483:Rivers; D053833:Wetlands; D015048:Zooplankton / Q000502:physiology*
chemical_list: D002734:Chlorophyll; D000077194:Chlorophyll A
keywords: Diatom bloom; Species diversity; Sundarban wetland; Tintinnids; Water quality