Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Mangrove Conservation Program
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Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Mangrove Conservation Program. www Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Mangrove Conservation Program. www Publication of Seacology-Sudeesa Mangrove Museum Special issue Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Seacology-Sudeesa Sri Lanka Mangrove Conservation Program. July 27th, 2018 Seacology-Sudeesa Northern Province Community Training Centre Vidathalathivu, Sri Lanka Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Mangrove Conservation Program. www Publication of Seacology-Sudeesa Mangrove Museum Special issue Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Seacology-Sudeesa Sri Lanka Mangrove Conservation Program. Volume 2, (1) July, 2018 ISSN 2602 – 8840 Editorial Board: Editor – in – Chief K.B. Ranawana, Department of Zoology, University of Peradeniya Editorial Assistance H.M.D.R. Herath, Department of Sociology, University of Peradeniya D.R.G.W.B. Ellepola, Department of Zoology, University of Peradeniya V.A.Sanjeewa Jayarathne, Department of Zoology, University of Peradeniya Publisher: Small Fisher Federation (Sudeesa), Sri Lanka Printed by: Sanduni Offset Printers (Pvt) Ltd No:4/1, Sarasaviuyana Goodshed Road, Sarasaviuyana, Peradeniya Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Mangrove Conservation Program. www CONTENTS Page no. Status of mangrove ecosystems in Northern Sri Lanka R.M.D. Alawathugoda, K.T. Premakantha, D.K.N.G. Pushpakumara, 1 T. Sivananthawerl, and M.G.W.M.W.T.B. Dissanayake Assessment of mangrove vegetation distribution, fishery and water quality in the 2 Nayaru lagoon, Mullativu, Sri Lanka G. Ellepola, K.B. Ranawana, and R. Chandrajith Leadership initiatives of the Sri Lanka Navy for rehabilitation and conservation 3 of marine environment including mangroves of Sri Lanka K. Nuwarapaksha Comparison of carbon stocks and carbon dioxide removal capacity of Hada Oya 4 estuary and Okanda creek mangrove ecosystems in the east coast of Sri Lanka M. G. M. Prasanna, K. B. Ranawana, and K. M. G. G. Jayasuriya Development of methods to preserve natural color and texture of salt marsh 5 plant specimens P.C. Premathilake Mangrove and associated ichthyofaunal diversity in Nasivanthivu pristine 6 ecosystem in Valaichenai lagoon K.Priyanka, J.M. Harris and M.Vinobaba 7 Distribution of Avicennia marina in the Jaffna district, Sri anka. P. Rajkumar, C.S. Wijesundara, and K.B. Ranawana Distribution of mangrove species in Anthanathidal and Kapputhu areas in the 8 Jaffna Peninsula, Sri Lanka P. Rajkumar, C.S. Wijesundara, and K.B. Ranawana Fisheries in mangroves of southeast coast of India for economic value and 9 ecological significance N. Rajendran and K. Kathiresan Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Seacology-Sudeesa Sri Lanka Mangrove Conservation Program. www STATUS OF MANGROVE ECOSYSTEMS IN NORTHERN SRI LANKA R.M.D. Alawathugoda 1, K.T. Premakantha 1, D.K.N.G. Pushpakumara 2, T. Sivananthawerl 2, M.G.W.M.W.T.B. Dissanayake 3 1 Forest Department, 2 Faculty of Agriculture, University of Peradeniya, 3 Ministry of Mahaweli Development and Environment Mangrove forests are among the most threatened ecosystems globally, and Sri Lanka has around 15,000 ha of mangrove forests distributed along its coastal belt covering 14 out of 25 administrative districts. Being located in densely populated areas, these mangrove forest patches are highly vulnerable for conversion to other land uses such as shrimp farming, salt manufacturing and other development projects, other than degradation through anthropogenic factors. Among total mangrove areas available, more than 40% is situated in Northern districts and the situation of these forests are not much studied compared to other areas due to the civil war that prevailed in the northern areas of the country. Therefore, a study was conducted in mangrove forest areas in four Northern districts, namely Jaffna, Mullaithivu, Kilinochchi and Mannar. The study covered 21 locations in these districts and assessed the growth condition, tree density, regeneration, species composition and biomass of mangrove vegetation. The data was collected on tree species, height and diameter at breast height (dbh) for trees (>10 cm dbh) and saplings (<10 cm dbh, >1.5 m height), and count of seedlings (<1.5 m height) in circular sampling plots (10 m radius plots for trees, 3m radius plots for saplings and seedlings). Biomass was computed using allometric equations developed for mangroves. Maximum number of species in terms of both trees and saplings found in a certain location was five in all districts, and the most frequently found species were Avicennia marina, Exoecaria agallocha and Lumnitzera racimosa. In general most of these vegetations are very low in height with average height of trees and saplings varying between 3-6 m and 2-4 m respectively. Most of the sites exhibited high density of saplings (trees less than 10 cm dbh) while tree (larger than 10 cm dbh) density was quite low. In Jaffna and Kilinochchi a large proportion of Basal Area (BA/ha) is coming from sapling category while in the sites in Mullaithivu tree category is more prominent to contribute to Basal Area. Above ground biomass of these forests are quite low compared to other mangrove vegetations. Seedling regeneration highly varies among different locations. Key words: Mangrove species, growth, forest structure, biomass Corresponding author: [email protected] Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Seacology-Sudeesa Sri Lanka Mangrove Conservation Program. www ASSESSMENT OF MANGROVE VEGETATION DISTRIBUTION, FISHERY AND WATER QUALITY IN THE NAYARU LAGOON, MULATIVU, SRI LANKA G. Ellepola1, K.B. Ranawana1 and R. Chandrajith2 1Department of Zoology, Faculty of Science, University of Peradeniya 2Department of Geology, Faculty of Science, University of Peradeniya Until recently, the lagoons in the north of Sri Lanka were neglected due to the prevailed civil war conditions. Therefore, their ecological significance, its contribution to local economy and the status of threat were not assessed previously. Findings of the current study provide information on above aspects of Nayaru lagoon, Sri Lanka. During the study in 2014, an extensive habitat mapping survey was carried out over a period of twelve months. The distribution of mangroves and their extent were estimated using line transect methods and fish data and daily catch information were collected based on information gathered at fish landing sites. Water samples were collected from several locations in the lagoon and they were chemically analyzed after being brought back into the lab. The Nayaru lagoon was located (9°06'-9°l0'N, 80°50'-80°53'E) in the northeast coast of Sri Lanka in the Mullaitivu District of Northern Province (1267 ha). The lagoon has a wide mouth located at the southeastern part of the lagoon. Nay Aru and Palidai Aru were the main freshwater sources to the lagoon entering from its western side. Eastern shore of the lagoon is devoid of mangroves while a well-developed mangrove cover was seen in the southern and western shores of the lagoon. Seven true mangrove species namely Avicennia marina, Exoecaria agallocha, Lumnitzera racemosa, Raizophora mucronata, Aegiceras corniculatum, Avicennia officinalis and Heritiera littoralis were recorded around the lagoon. The mangroves were dominated by Avicennia maraina (relative density 60.6%) and Aegiceras corniculatum, Avicennia officinalis and Heritiera littoralis were the least abundant species. Cynometra iripa was a rare mangrove associate recorded in the area. The lagoon supported a rich fishery and villagers in Nayaru, Alamphil, Chemalai and Kumulmunai depends (479 registered fishermen) on the lagoon fishery as a regular income source. Gill nets, cast nets, hook and line and crab traps are the major fishing gear used by the fishermen. Seventeen species of fin fish belonging to 15 families, the mangrove crab Scylla serrata and Fenneropenaeus indicus were harvested from the lagoon. Bulk of the catch was represented by Mugil cephalus (52%) and other abundant species were Chanos chanos, Lates calcarifer, Arius bilineatus and Eleuthronema tetradactylum. About 29% of the total catch was represented by shellfish species where Scylla serrata was the most abundant. The estimated annual yield of the lagoon was 9.237 Kg ha-1 year-1 which is a lower amount compared to other shallow coastal lagoons in Sri Lanka. 3- Maximum PO4 concentration in the lagoon was around 0.27 mg/L during the dry season. Due to the 3- high PO4 loads an uncontrolled growth of the filamentous algae in Kumulamunai side of the lagoon was observed. Alteration to the hydrological regime of the lagoon was observed as a threat to the lagoon ecosystem and its fisheries. Key words: water quality, fishery, hydrology Corresponding author: [email protected] Proceeding of the International Symposium on Mangrove Ecosystems 2018 of Seacology-Sudeesa Sri Lanka Mangrove Conservation Program. www LEADERSHIP INITIATIVES OF THE SRI LANKA NAVY FOR REHABILITATION AND CONSERVATION OF MARINE ENVIRONMENTS INCLUDING, MANGROVES OF SRI LANKA K. Nuwarapaksha Senior Staff Officer (Marine Conservation & Monitoring Unit), – Sri Lanka Navy Mangroves are an important marine ecosystem in Sri Lanka which covers more than 15,000 ha of the country. Various human and natural impacts such as development,