Organizational response to disaster -the case of tsunami, December 2004

The Tsunami struck Sri Lanka on 26th December 2004, causing an enormous devastation of human lives and property. State and non-state sectors being unprepared and poor coordination of international and local assistance left people internally displaced even after one year of the disaster. Using primary and secondary data, the study assessed the responsiveness of the organizations to the Tsunami disaster in the Galle district and developed a model of action for effective disaster management.

The study identified the response levels of the organizations at relief, recovery, reconstruction, rehabilitation and development stages. There was no pre-preparation for a major disaster in Galle district. The disaster relief was provided by unplanned emergent structures. The prevailing administrative structures, political institutions, Center for National Operations, Non-governmental organizations, volunteers and community-based groups provided relief for two months. The government established the emergency operation structures for national level coordination.

At the recovery stage community and the private sector organizations have been marginalized in the response system. Governmental and NGOs have focused on providing transitional shelters and dry rations. The reconstruction and rehabilitation stages have focused on housing, livelihoods, social rehabilitation and infrastructure, which were in progress through September 2006. The Galle district emergency operation center completed the Disaster management plan for the district in July 2005. The parliament of Sri Lanka approved the Sri Lanka Disaster Management Act, No 13 of 2005, under which the National Disaster Management center has been established.

The model identifies organizational structure to coordinate donor assistance and link to community needs, through national and local level coordinating institutions with the contribution of different sectors and with proper monitoring. Getting the vulnerable community to actively participate in disaster management activities leading towards development will minimize the damage. Suggestions are made for specific capacity building measures for the different levels of the institutional model.

S F Ansar and M W A P Jayatilaka
Department of Agricultural Extension, University of Peradeniya, Sri Lanka.

Identification of resilient species for maritime vegetation affected by tsunami in Hambantota district of Sri Lanka

Among the many coastal districts struck by the Tsunami disaster, Hambantota District in the Southern region, suffered heavy losses to the coastal vegetation, biodiversity, increase salinity level of crop lands and water pollution, thus transforming the coastal area unsuitable for agriculture. A field survey was conducted to identify the damaged/ tolerant/ recovered species of maritime vegetation at three stages (1 week, 1 month and 6 months after Tsunami).

Within one week of Tsunami, all Banana (Musa Spps) plants, Mango (Mangifera indica), Citrus Spps, and Fish tail palms (Cariyota urenus) were found to be dead. At the same time Coconut (Cocos nucifera), Tamarind (Tamarindus indica), Ipil ipil (Leucaena leucocephala), Sooriya (Drespesia populrea) Maliththa (Salvadora persica), Kottamba (Terminalia catappa), Wal beli (Hibiscus tiliaceus) and Diya mudilla (Barringtonia asiatica) were not damaged by Tsunami. Some Cinnamom (Cinnamomum verum) plants, Jak (Artocarpus heterophylus), Bread fruit (Artocarpus altilis), Teak (Techtonia grandis), Kohomba (Azadirechta indica), Terminalia catappa and Wood apple (Feronia limonia) were defoliated. Pandanus tectorius plants, which were established in near the sea, were almost unaffected.

It was observed that one month after Tsunami, Mangifera indica, Beli (Eagle marmelos), Billing (Averrhoea bilimbi), Areconut (Areca catechu) and Cariyota urenus have not recovered. In contrast, some plant species such as Azadirachta indica, Tamarindus indica, Cocos nucifera, Leucaena leucocephala, Pandanus, Terminalia catappa, Acacia spps, Callophylum inophylum and Katu andara (Prosopis juliflora) have survived.
Six months after tsunami, some defoliated tree species have started to produce new flushes, showing complete recovery (> 90 %) (Azadirachta indica, Tamarindus indica, Feronia limonia, Zisipus jujuba, Salvadora persica and Manilkara hexandra). About 30 % recovery rate was observed in Artocarpus nobilis and Terminallia catappa. Artocarpus nobilis plants were rejuvenated; young shoots were seen in mature stems of the plant. Some herbs were found in coastal belt, Nagadarana, Tridax procumbanse, Attana (Datura spps) and Maturutala. Antigonan spps and Muhudu bimthambaru (Ipomoea pescapre) were seen as creeping type plants. Crowfoot grass and Bala thana grass were also recorded near the coast. Although practically no damage was recorded for Katu andara, in some certain areas of Hambantota District, it has started to germinate, where it was not present may be due to high tolerance to salinity.

Tree species of Pandanus, Cocos nucifera, Terminalia catappa, Manilkara hexandra ,Berringtonia asiatica, Prospis juliflora, Azadirachta indica, Hibiscus tiliaceus, Sooriya, Tamarindus indica, Salvadora persica and Feronia limonia and shrubs species of Maduruthala, Tridax, ‘Nagdarana, Attana and Wara (Calotropis gigantean), and creeping type plants species of Balathana grass, Crowfoot grass, Neranchi, Ipomoea pescapre can be recommended for rehabilitation of maritime vegetation of affected areas in Hambantota District.

K M C Fernando, S Subasinghe and A A Kumara
Department of Crop Science, Faculty of Agriculture, University of Ruhuna, Kamburupitiya, Sri Lanka

Impact of post – tsunami rehabilitation activities on selective fishing in the Northern coast of Jaffna peninsula

A questionnaire based survey was conducted in May 2006, among the Tsunami affected fishermen of Northern Jaffna peninsula, in order to assess the fishing effort after Tsunami rehabilitation activities. 4337 families along the coast from Valvettithurai to Kaddaikadu were included in to the survey and they were divided in to 72 sites according to their respective donor agencies. 16 Non governmental organizations were identified as donor agencies for permanent housing schemes, out of which 6 agencies directly donated fishing gears and boats. The types and numbers of fishing gears and boats used before and after tsunami were recorded.

Results indicate that all the traditional canoes have been replaced by fiber reinforced boats and the number of boats showed 12% increase after tsunami. Before tsunami, there were diverse types of fishing gears with wide range of mesh size. But post tsunami rehabilitation aids provided only the gill nets of 2 different mesh sizes, one for fish and the other for skates. Although large numbers of boats have been given, most of them are not in use because of the prevailing unrest situation in this region. Therefore fishing effort due to the increased number of boats is immaterial. But reduced diversity of fishing gear will have major impact on stock. Since fishing is restricted in to a narrow belt along the coast repeated use of skate gill net by most of the fishermen will lead to an over exploitation of skate species. Similarly, selective fishing by gill net will deplete coastal fish species. Therefore donor agencies should focus on remedial actions in order to diversify the fishing gears in type and in mesh size.

S Kugathas, Y Sivatharshan, and K Sivashanthini
University of Jaffna, Sri Lanka

Assessment of tsunami damage on the coastal vegetation in 3 selected locations in Yala National Park

Tsunami, the killer wave swept nearly two thirds of the coast of Sri Lanka on 26th of December, 2004. About 40,000 people died and around 500,000 people were displaced, more than 119,000 houses damaged either fully or partially. About 13 coastal districts were directly affected, the north and east suffered the brunt of the blow accounting for about 2/3 of deaths and 60% of displacements. In terms of ecological aspects, with the exception of few species, most of the vegetation suffered total or partial death, lagoons, estuaries, coral reefs, sea grass beds, salt marshes and mangroves experienced the damage at varying levels.

A study was conducted in 3 Tsunami affected locations in Block 2 of the Yala Natoinal Park with a view to assess the condition of the vegetation more than 1.5 years after the incident. In each site, 3 plots which were 10 x 10m were demarcated the vegetation including trees, shrubs and ground vegetation was assessed. A tsunami non affected site in close proximity to the study sites was taken as the control. Direct observations were also made on the dead plants, regenerated one, other external differences observed (color changes etc.). Shannon’s Diversity Index (Diversity, Evenness and Dominance) and Stand Variables such as Relative Frequency and Relative Density were calculated using the data. In addition to the vegetation, soil and water were also assessed for pH, conductivity, salinity etc. The measurements were repeated twice in the experimental period of 6 months.

51 species which belongs to 30 families were observed (without ground vegetation) in the 27 plots studied. The stand variables did not differ significantly between the 3 sites studied. However, some species had higher proportional abundances in Tsunami affected sites compared to those which were not affected. Kathurupila (Tephorosia purpurea), Lunuwarana (Crateva religiosa), Ranawara (Cassia auriculata) were more prominent in the Tsunami affected sites in Mahaseelawa compared to the non affected sites in the same location. Patassa was seen abundantly in non tsunami affected sites. Korakaha (Memecylon umbellotum) and Katupila (Tephorosia purpurea) were most abundant among the shrubs in tsunami affected areas while Wal pichcha (Momordica diocia) was prominent in unaffected areas. In the Patanangala site, among the trees Elabatu was seen quite prominently (Solanum xanthocarpum). Attana (Datura metel), Wal kochchi (Croton bonplandianus) recorded the highest proportional abundance. In non tsunami affected areas Gandapana (Lantana camara) and Maduruthala (Hortinia horibunda) recorded the highest abundance. In Buthawapitiya site Lunuwarana (Crateva religiosa) , Ranawara (Cassia auriculata), Katupila (Tephorosia purpurea), and Pila (Tephorosia purpurea ). Andara (Acacia leucophloea) was seen in both tsunami affected and non affected areas.

In general, four species were observed to be dominant in the vegetation in the Tsunami affected areas ie, Walkochchi (Croton bonplandianus), Attana (Datura metal), Kathurupila (Tephorosia purpurea). Leguminosae and Euphorbiaceae were the most dominating families in species of this Tsunami affected sites and Rubaceae and Oleaceae were the most dominant species in Tsunami not affected areas.

The water quality showed significant variation between the sites studied while soil parameters were not significantly different. The electrical conductivity of water was highest in Bathuwapitiya site pH did not show significant difference between sites. Buthawapitiya recorded high salinity values compared to other sites. Soils did not record values which were significantly different.

(SME ’s were considered to be business that had employed less than 25 workers and less than Rs.5 Mn turn over in immediately preceding 12 months period.)

P Wijesinghe1 and D M S H K Ranasinghe2
1 Urban Development Authority
2 Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka

Organizational response to disaster -the case of tsunami, December 2004

The Tsunami struck Sri Lanka on 26th December 2004, causing an enormous devastation of human lives and property. State and non-state sectors being unprepared and poor coordination of international and local assistance left people internally displaced even after one year of the disaster. Using primary and secondary data, the study assessed the responsiveness of the organizations to the Tsunami disaster in the Galle district and developed a model of action for effective disaster management.

The study identified the response levels of the organizations at relief, recovery, reconstruction, rehabilitation and development stages. There was no pre-preparation for a major disaster in Galle district. The disaster relief was provided by unplanned emergent structures. The prevailing administrative structures, political institutions, Center for National Operations, Non-governmental organizations, volunteers and community-based groups provided relief for two months. The government established the emergency operation structures for national level coordination.

At the recovery stage community and the private sector organizations have been marginalized in the response system. Governmental and NGOs have focused on providing transitional shelters and dry rations. The reconstruction and rehabilitation stages have focused on housing, livelihoods, social rehabilitation and infrastructure, which were in progress through September 2006. The Galle district emergency operation center completed the Disaster management plan for the district in July 2005. The parliament of Sri Lanka approved the Sri Lanka Disaster Management Act, No 13 of 2005, under which the National Disaster Management center has been established.

The model identifies organizational structure to coordinate donor assistance and link to community needs, through national and local level coordinating institutions with the contribution of different sectors and with proper monitoring. Getting the vulnerable community to actively participate in disaster management activities leading towards development will minimize the damage. Suggestions are made for specific capacity building measures for the different levels of the institutional model.

S F Ansar and M W A P Jayatilaka
Department of Agricultural Extension, University of Peradeniya, Sri Lanka.

Hydrogeological condition and groundwater quality distribution in the tsunami affected Southern coastal area of Sri Lanka

Groundwater monitoring in the tsunami affected southern coastal Weligama bay area was conducted during May 2005 to July 2006 to determine the hydrogeological conditions and groundwater quality by selecting 90 dug wells where water level, electrical conductivity (EC), total dissolved solids (TDS) and pH was measured in monthly interval. The Weligama bay area is located in latitudes and longitudes of 80022’, 5097’. The dug wells are sunk into the permeable quaternary sand deposits in the coastal margin at Weligama Bay area is very permeable and hydro-geological conditions are very favorable for saltwater intrusion.

The study helped to prepare groundwater isograph map and the distribution of EC, TDS and pH maps using the GIS package MAPINFO. Groundwater isograph map help to identify groundwater distribution of the coastal area of Weligama. There exist a closed relationship between topographical map & groundwater contour map.

The results of the study revealed that the Electrical conductivity of well water in all wells situated in the Tsunami affected Zone are turned to be saline (EC in average increases from 1500 µ Siemens per cm to around 4000 µ siemens /cm.). According to the hydrographs prepared during the study period, unconfined quaternary aquifer ground water level intimately related to atmospheric precipitation. The characteristic of the hydrograph provides a conclusion, that the recharge of unconfined ground water in quaternary aquifer takes place during the period of monsoon rain and quality of ground water due to tsunami has not changed specially.

R U K Piyadasa1, K D N Weerasinghe2, D S E Kumara2, H K C S Lakmal2
J A Liyanage3

1 Department of Geography, University of Colombo, Sri Lanka
2 Department of Agricultural Engineering, , University of Ruhuna, Sri Lanka
3 Dept of Chemistry, University of Kelaniya, Sri Lanka

Assessment of tsunami damage on the coastal vegetation in five selected districts in the coastal zone of Sri Lanka, after one and half years of tsunami

Tsunami, the killer wave swept nearly two thirds of the coast of Sri Lanka on 26th of December, 2004. About 40,000 people died and around 500,000 people were displaced, more than 119,000 houses damaged either fully or partially. About 13 coastal districts were directly affected, the north and east suffered the brunt of the blow accounting for about 2/3 of deaths and 60% of displacements. In terms of ecological aspects, with the exception of few species, most of the vegetation suffered total or partial death, lagoons, estuaries, coral reefs, sea grass beds, salt marshes and mangroves experienced the damage at varying levels. This study was conducted with the patronage of the Food and Agricultural Organisation of the UN to scientifically assess the response of the coastal ecosystems with special reference to coastal forests to the Tsunami, almost one and half years of the incident.

The study focused on 5 tsunami affected districts namely, Kalutara, Galle, Matara, Hambantota and Ampara. In each district, approximately 6 sampling locations selected based on the topography maps and ground information. In each sampling location, a transect which was 10m wide and upto 250m inland was taken. The transect was divided into 50m blocks, the first one laid at the start of vegetation line of the beach. In each 50m section of the transect, all the plant species were enumerated. For the ground vegetation, percentage ground cover was taken. Using an index, the level of damage was evaluated for each plant. Composite soil samples were taken at each 50m segment and analysed for Electrical Conductivity, Soil Organic Carbon and major nutrients. Water samples were taken from existing wells located close by.

Although most of the vegetation, except for few exceptions, suffered badly at the time of Tsunami, there was extensive regeneration on the coast at the time of our study. The species which suffered the tsunami damage most were Palmyrah palm (Borassus flabellifer), Del (Artocarpus nobilis), Araliya (Borassus flabellifer), Puwak (Areca catechu), Banana (Musa spp), Kitul (Caryota urens), Guava (Psidium guajava), Avacardo pears (Persea gratissima), trees of Citrus family ie Oranges, Lemon, Lime (Citrus spp.) Alstonia, Teak (Tectona grandis) etc. Of these, most of the species had regenerated to varying degrees, the most difficult ones being Araliya, Palmyrah, plants of citrus family, Kitul, Guava.

With a view to find out the species which are more robust in the regeneration, percentage ground cover (in ground vegetation) and relative abundance (in tree/shrub vegetation) were taken in each 50m segment of a plot. The districts did not vary significantly in the biodiversity. However, the species abundance showed a significant variation especially between the districts of the western coast (Kalutara, Galle, Matara) with that of south and eastern coasts (Hambantota and Ampara). While Mudu bim thamburu (Ipomea pescaprae) was the most prominent ground cover in the western districts, Maha ravana ravul (Spinifex spp.) was more prominent in both south and eastern districts. With regard to the abundance of trees/shrubs, Wetakeiyya (Pandanus sp), Coconuts (Cocos nucifera), Gam suriya (Thespesia spp.), Mudilla (Barringtonia spp.), Domba were most abundant. In the South and Eastern districts, Maliththan (Woodfordia fruitocosa), Andara (Prosopis juliflora), Palmyrah palm, Cashw nut (Anacardium occidentale) and Neem (Azadirachta indica), Indi, (Phoenix spp) Korakaha/ Kayan (Memecylon angustifolium) were prominent. In the South and South-eastern districts, Aththana (Datura metel), Wal kochchi had spread into invasive levels while the regeneration of Ranawara (Cassia auriculata) also had increased.

With regard to the physical parameters, soil carbon content showed a decrease with the increase in distance from the beach. The Electrical Conductivity (EC) also showed a decreasing trend with the increasing distance from the beach in all the districts studied. In general, all the nutrients (Total N, Available P, Available K, Ca, Mg and Na) showed an increase upto about 50m compared to that of non tsunami levels and then decreased. The pH of the water samples taken in all the districts were between 7-8 indicating a neutral level while the EC values were higher than the standard of 4 mil semens.

With regard to the establishment of Green Belt, the coastal area could be broadly categorised into natural, rural and urban landscapes. For the natural landscapes like mangroves, sand dunes and coastal forests, facilitation/restoration of the natural vegetation is recommended. Selection of species should be in line with the naturally occurring ones in the ecosystem. In total locations, planting a strip of natural littoral woodland and strand plants seaward of agricultural crops is suitable. For urban locations, patches of natural vegetation could be integrated as far as possible with the most suitable concept for the area. There could be open grassed/sandy/paved parks or playgrounds or sports grounds of various sizes, provided there is a substantial belt of trees on the seaward side, and in cyclone prone areas, wind shelter belts on all sides. In cyclone prone areas, wind shelter belts should be planted around crops and settlements: the trees and shrubs used could be introduced species as well as indigenous/ native (found naturally in Sri Lanka) and endemic (found naturally only in Sri Lanka) species.

The design of the Green belt should include both ground vegetation, shrubs and then trees. Based on the study results, composition of the vegetation for both ground vegetation, shrub layer and the tree layer has been proposed for all the 5 districts. In the tree layer, there were two distinctions, one for the bioshield which is located at close proximity to the sea and then the trees outside the bioshield comprising of more multipurpose ones serving both protection and production purposes. Further, general designs were recommended for the west coast and southeast and eastern coasts. Guidelines were also proposed for rehabilitation of the mangrove areas and sand dunes.

D M S H K Ranasinghe and W M P S B Wahala
Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka

Post-tsunami natural regeneration of coastal vegetation in the Hambantota district in south-eastern Sri Lanka.

A qualitative rapid survey was conducted in 45 plots distributed in the gentle seashore vegetation and sand dunes (n = 13), coastal scrublands (n = 19), and mangroves (n = 13) along the coastline of Hambantota District, affected by the Indian Ocean tsunami. The objective of the survey was to investigate the natural regeneration of coastal vegetation 20 months after the tsunami disturbance.

21 plant species belonging to 19 families were recorded as the prominent plants regenerating in affected mangroves, while 16 species in 15 families and 32 species in 23 families were observed as prominent plants to regenerate in affected areas of the gentle sea-shore vegetation and coastal scrublands respectively.

In tsunami affected mangrove stands Acanthus ilicifolius (in 50% of study plots), Achrosticum aureum (40%) and Lumnitzera racemosa (17%) were the dominant species establishing in open muddy substrates, while Clerodendrum inerme (57%), Lumnitzera racemosa and Excoecaria agallocha (29% each) were regenerating in sand deposited in the mangrove patches.

Ipomoea pes-caprae (85%), Scaevola taccada and Calotropis gigantea (23% each) were observed as the dominant species re-establishing in the gentle seashore vegetation, while Spinifex littoreus shows a slow rate of regeneration. Most of the destroyed Pandanus odoratissimus bushes facing the beach are not regenerating. Instead a new row of Pandanus was observed regenerating immediately backing the original stands. Prominent species regenerating in coastal scrublands are Croton bonplandianus and Gymnema sylvestre (37% each), Clerodendrum inerme (16%), Calotropis gigantea (10%) and Crateva adansonii (10%) and saplings of Azadirachta indica and Limonia acidissima.

Invasive alien plants, mainly Opuntia dillennii have established well and spreading vigorously in affected coastal scrublands (58%), some study plots of gentle seashore vegetation (31%) as well as on sand depositions in the affected mangroves (15%). This species was observed replacing the spaces occupied by destroyed Pandanus odoratissimus bushes and Spinifex littoreus beds. Invasive alien plants such as Prosopis juliflora and Lantana camara were also spreading in tsunami disturbed coastal scrublands.

M S J Perera1, C N B Bambaradeniya2, P G D R Perera3, V A M P K Samarawickrema2 and H D D C K Perera2
1Department of Natural Resources, Sabaragamuwa University of Sri Lanka,
Sri Lanka.
2The World Conservation Union (IUCN), Sri Lanka Country Office, Colombo,
Sri Lanka.
3The Open University of Sri Lanka, Sri Lanka.

Coordination and information management mechanisms of the tsunami emergency and rehabilitation operations in agriculture, fisheries and forestry sectors in Sri Lanka

The widespread destruction caused by tsunami on December 26, 2004 brought a heavy toll on livelihoods and natural resources in the three sectors. Numerous international and national organizations assist the affected areas with main aim of restoring shattered livelihoods and for rehabilitation of natural resources for sustainable use by mitigating such disasters in the future.

Several projects were initiated to assess the damages and to restoring to build those back better. However, due to increasing number of emergency and rehabilitation projects in affected areas, there is a problem of coordination and sharing resources. Therefore, this study was focused to assess present status of coordination activities, to share experiences and knowledge for development of sustainable future plans and strategies for coordination and information management in the long run.

The study examined and reviewed the current situation with multi stakeholder participation from government, non government, private sector and community with regard to objectives of the study. Outputs were categorized under; overall status of mechanisms, opportunities for further development and improvement mechanisms best suited for Sri Lanka in line with the “build back better” strategy, and the way forward in terms of information management, exchange and coordination mechanisms for future work.

The study revealed that the need of cross sectoral coordination and information sharing is essential due various reasons such as large volume of information, as to achieve better accuracy and targeting etc., The study proposes to setup divisional/district level mechanism and focal point for coordination and information sharing among Government, donor, private agencies and I/NGOs. There will be similar setup at provincial and national level. The study further proposes certain guidelines such as, to have a focal point in each agency for dissemination of information, making coordination mandatory than voluntary, ethics in data use, giving due regard for Information management process by way of collection of specific data, sharing of data etc., Finally, two models are proposed for coordination and for information sharing among three main sectors.

W M B S Nissanka
Reconstruction and Development Agency (RADA), Colombo 01, Sri Lanka

Designing green belts in the coastal zone of Hambantota

Tsunami, which occurred in the Indian Ocean on 26th of December, 2004 caused severe damage to Sri Lanka’s coastline. Hambantota District, situated in the south of the country was among the worst affected. 19 GS Divisions in the Districts were affected. As a measure towards protection of the coastline from future such hazards, establishment of a green belt has been suggested by the Government. The location of this belt was proposed to be in the strict conservation zone of the coast which was 100m in the western coast and 200m in the eastern coast. The limits were then revised and the present reservation limits were in accordance with those listed in the Revised Coastal Zone Management Plan 1997.

The present study was conducted with a view to design a green belt for Hambantota District. It was hoped to recommend the most suitable species and their arrangement taking into consideration the natural landscape features of the coastline. Further, the modalities of the implementation of such a belt also was discussed with the existing organisations in the District including govt,, non govt, private and the communities.

The exact study area was limited to the coastline between Kudawella to Kubukkan Oya. Data were collected in 12 sampling locations. The methods used for data collection were, reconnaissance survey, floral sampling, focal group discussions and community survey. In the floral sampling, a transect of 10m x 50m was established from the beach towards the inland at each sampling location and all the species were identified. The intention of this was to identify the species which are most resistant to coastal hazards. Focal group discussions were held with the key players in the green belt establishment in the District. The main aim of this was to identify their level of support and willingness to participate in the Green Belt.

According to the results, the coastline of Hambantota can be divided into natural, rural and urban areas. Among the natural areas, mangroves and sand dunes were prevalent. Recommendations are given in the use of most suitable plants for individual areas in the District ie Rekawa, Yala National Park. Mahalewaya, Rathupasgodalla and rural areas. Many govt, and non govt. organisations were involved in tree planting. However, there was no coordinated effort. The neighbouring communities expressed their willingness to participate in this exercise especially in tree planting and maintenance.

N I Kalasinghe1, and D M S H K Ranasinghe2
1National Aquatic Research Agency (NARA), Mattakkluliya, Sri Lanka.
2Department of Forestry & Environmental Science, University of Sri Jayewardenepura