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Thesis Submitted to in Partial Fulfilment of the Requirements for the Award Of BIOECOLOGICAL STUDY OF BENTHIC COMMUNITIES IN THE KODUNGALLUR-AZHIKODE ESTUARY, SOUTH WEST COAST OF INDIA Thesis submitted to Cochin University of science and technology In partial fulfilment of the requirements for the award of the Degree of Doctor of Philosophy In MARINE BIOLOGY under the FACULTY OF MARINE SCIENCES JAYACHANDRAN P.R. (Reg. No. 4278) Department of Marine Biology, Microbiology and Biochemistry School of Marine Sciences Cochin University of Science and Technology Kochi-682016 December 2017 Bioecological study of benthic communities in the Kodungallur-Azhikode Estuary, South West Coast of India Ph.D. Thesis under the Faculty of Marine Sciences Author Jayachandran P.R. Research Scholar (Full time) Department of Marine Biology, Microbiology and Biochemistry School of Marine Sciences, Cochin University of Science & Technology Kochi - 682 016, Kerala, India e-mail: [email protected] Supervising Guide Dr. S. Bijoy Nandan Professor Department of Marine Biology, Microbiology and Biochemistry School of Marine Sciences Cochin University of Science and Technology Kochi - 682 016, Kerala, India e-mail: [email protected] December 2017 Department of Marine Biology, Microbiology and Biochemistry School of Marine Sciences Cochin University of Science & Technology Dr. S. Bijoy Nandan Professor Email: [email protected] This is to certify that the thesis entitled “Bioecological Study of Benthic Communities in the Kodungallur-Azhikode Estuary, South West Coast of India” is an authentic record of research work carried out by Mr. Jayachandran P.R. (Reg. No. 4278), under my scientific supervision and guidance in the Department of Marine Biology, Microbiology and Biochemistry, Cochin University of Science and Technology, in partial fulfilment of the requirements for the Degree of Doctor of Philosophy in Marine Biology, School of Marine Sciences, Cochin University of Science and Technology under the faculty of Marine sciences and that no part thereof has been presented before for the award of any other degree, diploma or associateship in any University. It is also certified that all the relevant corrections and modifications suggested by the audience during the pre-synopsis seminar and recommended by the doctoral committee have been incorporated in the thesis. Kochi - 682 016 Dr. S. Bijoy Nandan December, 2017 (Supervising Guide) DECLARATION I hereby declare that the thesis entitled “Bioecological Study of Benthic Communities in the Kodungallur-Azhikode Estuary, South West Coast of India” is an authentic record of research work done by me under the supervision of Dr. S. Bijoy Nandan, Professor, Department of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Technology, in partial fulfilment of the requirements for the Degree of Doctor of Philosophy in Marine Biology, School of Marine Sciences, Cochin University of Science and Technology under the faculty of Marine sciences and no part of this has been presented for any other degree or diploma earlier. Jayachandran P.R. Kochi - 682 016 December, 2017 ACKNOWLEDGEMENT I express my profound sense of gratitude to my supervising guide Dr. S. Bijoy Nandan, Professor, Department of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, CUSAT for his invaluable pieces of advice, constant inspiration and patient criticisms throughout the tenure of my research work. At each critical juncture, he guided me, the appreciation given for my small efforts gave me the confidence to proceed, his unconditional support since deciding the topic to the submission of thesis is exemplary. I am grateful to the current and former Deans and Directors of the Faculty of Marine Sciences, CUSAT for their support. I am greatly indebted to Prof. (Dr.) Rosamma Philip, the Head, Department of Marine Biology, Microbiology and Biochemistry for the support and encouragement I received throughout my research period. The support and encouragement offered by Dr. K.J. Joseph (Retired Professor of department) during the initial period of my research work has been an important influence in structuring this thesis. The kind consideration and encouragement of Prof. (Dr.) Aneykutty Joseph, Prof. (Dr.) A.A. Mohamed Hatha, and retired Professors of the department, Dr. R. Damodaran, Dr. C.K. Radhakrishnan, Dr. Babu Philip and Dr. A.V. Saramma is duly acknowledged. I am also thankful to other faculties of the department Dr. Priyaja P., Dr. Swapna P. Antony, Dr. K.B. Padmakumar and Dr. Manjusha. K.P for their support and encouragement. I am greatly indebted to the Kerala State Council for Science, Technology and Environment for the financial assistance under the scientific research project entitled “Ecology and fish production potential of the Kodungallur-Azhikode backwater ecosystem”. I wish to keep on record my wholehearted and sincere gratitude to the Director and office staffs of School of Industrial fisheries for availing the facilities for field sampling by “R.V. King Fisher” also thankful to Mr. Anilajan P.B. and Mr. Suresh M.A. (crew members) for helping and caring me throughout the sampling. I am also thankful to the people of Kodugallur-Azhikode area for their cooperation and love throughout the sampling period. The support provided by my colleague Ms. Sreedevi O.K. during the sampling period and further analysis are greatly acknowledged. I owe gratitude to the administration and supporting staffs of Department of Marine Biology Microbiology and Biochemistry, School of Marine Sciences and Main Campus of CUSAT for the support throughout my research period. I am grateful to current and former Librarian and support staffs of the School of Marine Sciences library for their help and cooperation. I am also thankful to Research Gate community for valuable feedback and support during the study. The assistance rendered by Dr. P. Graham Oliver (National Museum of Wales, and Bangor University, Dr. Hugo H. Kool and Dr. Henk Dekker (Naturalis Biodiversity Center, Leiden, The Netherlands), Anders Hallan (Australian Museum, Sydney), Dr. Ronald Fricke (SMN.H.S, Germany), Kevin Webb (NHMUK, UK), Dr. Richard Preece (University Museum of Zoology, Cambridge), Dr. S. Ajmal Khan (Retired Professor, The Centre of Advanced Study (CAS) in Marine Biology, Annamalai University), Dr. Naidu S.A. (ICMAM, Chennai), Dwi Listyo Rahayu (IISI, Indonesia), Dr. Subba Rao (former scientist ZSI), Dr. Deepak Samule (NCSCM, Chennai) and so many are greatly acknowledged. Encouragement and support of Prof. (Dr.) P. K. Abdul Azis (Former vice-chancellor of CUSAT & Aligarh Muslim University, Dr. N.G.K. Pillai (Former Scientist, CMFRI, Kochi), Dr. D. Mohan, Scientist, (ICMAM-PD, Chennai), Dr. M. Harikrishnan (Director, School of Industrial fisheries, CUSAT, Kochi), Dr. Abdul Jaleel (Scientist, NIO-RC, Kochi), Dr. Prabhakaran M.P. (Assistant professor, KUFOS, Kochi), Dr. K.K. Subhash Babu (Assistant professor, University of Jimma, Ethiopia), Dr. Shyam Kumar (Assistant professor, Maharajas College, Kochi), Dr. Mujeeb Rahman (Assistant professor, MES College, Ponnani), Dr. Naveesn Sathyan and Mr. Anilkumar P.R. (IISESR, Trivandrum), Dr. Mangala Unni, Dr. Harishankar H.S., Dr. Smitha C.K., Dr. Lathika Cicily, Dr. S. Vineetha, Dr. V. Ambily, Dr. Thasneem T.A., Dr. Anu Pavitran, Dr. Sreekumar, Mrs. Jini Jacob, Mr. Akhilesh Vijay, Mrs. Asha C.V., Mrs. Geetha P.N., Mrs. Sreelakshmi S., Mrs. Philomina Joseph, Mrs. Rani Varghese, Mrs. Preethy C.M., Mrs. Sajna, Mrs. Neelima Vasu, Mrs. Regina Hershey, Mrs. Retina I. Cleetus, Mrs. Krishnapriya P. P., Mrs. Radhika R., Mrs. Athira Krishnan, Mrs. Rakhi Gopalan, Mrs. Kapila K., Mrs. Vijayalakshmi K.C., Mrs. Emilda Rosmine, Mrs. Jisha Kumaran, Ms. Anu P.R., Ms. Santu K.S., Ms. Vineetha, Ms. Sruthy Sebastian, Mr. Susan P.S., Mr. Midhun A.M., Mr. Don Xavier N.D., Mr. Sanu V.F., Mr. Aji Mathew, Mr. Vishnu Sagar, Mr. Akhil Gosh, Mr. Aravind E. Haridas, Mr. Jabir T., Mr. Abhijith M. and so many for their kind consideration and willingness to help at any time. I also have pleasure in acknowledging my M.Sc. classmates for their help. I wish to express heartfelt gratitude to my loving mother Renuka P.K, father Mr. Rajakumar N.P., brother Mr. Visudhan P.R., sister in law Mrs. Rajeswari and my nephew Mr. Guruchinthanan V., without whom I would not have been able to complete this work on time. I am grateful to my wife Jima M. who allowed me to pursue this dream, also my heartfelt thanks for her immense love and support. I also thank my in-laws for their support. Throughout this journey, there have been many people, family, friends, acquaintances and even strangers who helped and supported me either knowingly or unknowingly, my sincere thanks to each of them. Above everyone else, I thank god who has inscribed me on the palms of his hands. Jayachandran Dedication To my parents, In consideration of love and affection INDEX Acknowledgements List of tables List of figures List of acronyms & abbreviations I. General Introduction 1-18 II. Study area, sampling design and analysis 19-38 II. 1. Study site: Kodungallur-Azhikode estuary 19 II. 2. Sampling design 22 II. 3. Hydrographic methods & analysis 23 II. 4. Sediment collection & analysis 26 II. 5. Collection, processing & identification of macrobenthos 27 II. 6. Collection, processing & identification of meiobenthos 28 II. 7. Feeding guild analysis 29 II. 8. Marine biotic indices 29 II. 9. Statistical methods and analysis 32 III. Hydrography and sediment characteristics 39-88 III. 1. Introduction 39 III. 2. Hydrographic methods 41 III. 2. 1. Rainfall 41 III. 2. 2. River discharge 41 III. 2. 3. Depth 43 III. 2. 4. Water temperature 43 III. 2. 5. Water turbidity 44 III. 2. 6. Water transparency (Secchi depth) 46 III. 2. 7. Salinity 47 III. 2. 8. Water pH 48 III. 2. 9. Water Eh 49 III. 2. 10. Dissolved oxygen 50 III. 2. 11. Biological oxygen demand 51 III. 2. 12. Dissolved nutrients 52 III. 2. 13. Chlorophyll-a 56 III. 3. Sediment characteristics 59 III. 3. 1. Sediment temperature 59 III.
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