Studies on the prevalence of algal blooms along Kerala coast, India

Jugnu, R (2006) Studies on the prevalence of algal blooms along Kerala coast, India. PhD thesis, Cochin University of Science and Technology, Cochin.

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Abstract

61 species of marine phytoplankton belonging to 32 genera were recorded from Chombala in north Kerala during the period from October 2001 to September 2002 (first year) and 76 species of 33 genera during the period from October 2002 to September 2003 (second year). From Vizhinjam, along south Kerala, 91 species of 30 genera and 90 species of35 genera were recorded in the sea in the first and second years respectively whereas in the adjacent bay 88 and 95 species belonging to 28 genera were recorded. 2. Diatoms and dinoflagellates, the two most diverse phytoplankton groups were rich in species diversity and density at both the sites, with the diatom species contributing the maximum to phytoplankton community structure. Blue green algae, mainly Trichodesmium sp was recorded from Chombala (12.5%) and Vizhinjam bay (8.3%) but was more frequent (25%) from Vizhinjam sea. A rapidophyte Chat/onella marina was recorded only from Chombala. Diatoms formed 83.5 % of the community at Chombala, while at Vizhinjam they formed 70.9"10, the reduction in contribution mainly due to the dominance of dinoflagellates; the diversity being controlled by the two genera Ceratium and Peridinium. 3. The annual average phytoplankton diversity index at Chombala was 1.88, of which the diversity of diatom and dinoflagellate were 1.81 and 0.29 respectively. 4. The diatom community at Chombala consisted of 10 families, of which members of the families Coscinodiscaceae (32.7%), Fragilaroideae(19.3%) and Biddulphiae (16.4%) were dominant Among the 7 families of dinoflagellates recorded at Chombala, Gymoodinaceae (24.3%), Peridinaceae (13.3%) and Ceratiaceae (13%) dominated the phytoplankton community structure. 5. The annual average phytoplankton diversity at Vizhinjam bay and sea were 2.13 and 2.09 respectively, of which the diversity indices of diatom and dinoflagellate in the sea were 1.85 and 1.15 and in the bay 1.5 and 0.98 respectively. 6. The diatom community at Vizhinjam sea consisted of 9 families of which members of Chaetocerae (28.4%), Fragilaroideap. (19"10), Biddulphiae (16.8%) and Coscinodiscacea (16.6%) were dominant. Among dinoflagellates, the families Dinophysiaceae (26.3%), Ceratiaceae (23.7%), Peridinaceae (36.1 %) dominated the phytoplankton community structure. At Vizbinjam bay, of the 9 families, members of Chaetocerae (21.6%), Fragilaroideat.(21.2%), Biddulphiae (17.3%) and Coscinodiscaceae. (16.3%) were dominant and among dinoflagellates, the families Peridinaceae (37.1 %), Dinophysiaceae (35.4%), Ceratiaceae (17 .9"10), dominated the phytoplankton community structure. 7. In the family Dinophysiaceae, the family in which DSP toxicity is shown by most of its members, two species were common Prorocellhlm micans was present in 6 and Dillophysis caudata in 15 out of the 24 sampled months at Vizhinjam.

Item Type:Thesis (PhD)
Supervisor(s):Kripa, V
Uncontrolled Keywords:algal blooms; Kerala coast; India
Subjects:Theses
Marine Environment > Algal Blooms
Divisions:CMFRI-Cochin > Fishery Environment
ID Code:7603
Deposited By:Dr. V Mohan
Deposited On:17 Feb 2011 17:13
Last Modified:20 Jan 2014 14:15

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