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Variations in Important Water Quality Parameters and Fish Species of Thondaimanaru Lagoon, Jaffna, Sri Lanka

2024-06-05T04:11:18Z

Title: Variations in Important Water Quality Parameters and Fish Species of Thondaimanaru Lagoon, Jaffna, Sri Lanka Authors: Shobiya, P.; Sivashanthini, K.; Sutharshiny, S.; Gunaalan, K. Abstract: Thondaimanaru lagoon is one of the shallow coastal lagoons in Jaffna peninsula. This study was conducted to assess the present status of water quality and fish species composition of this lagoon. Water sampling was conducted from July 2016 to December 2016. Nine random samples were collected monthly in order to determine water temperature, pH, salinity, Dissolved Oxygen, Total Dissolved Solids, Electric Conductivity and turbidity. A smarTROLL Multi parameter (Insitu 458389) was used to measure all the parameters except turbidity, which was measured by turbidity meter (2100Q HACH). Random samples of fishes were collected once a month. One-way ANOVA was used for statistical analysis. Water temperature, Electric Conductivity, Total Dissolved Solids, Dissolved Oxygen, salinity and turbidity showed significant variations (p < 0.05) whereas pH value did not show a significant difference (p > 0.05) among the months. Chanos chanos, Hemirhamphus sp., Nematalosa nasus, Mugil cephalus, Liza parsia, Oreochromis mossambicus, Arius caelatus and Gerres lucidus were present throughout the study period. Results revealed that the important water quality parameters fluctuated due to seasonal environmental changes. As a result of the shallow water level, rate of evaporation as well as precipitation had a significant influence on the water quality characteristics.

Marine Fungal Diversity and its Bioprospecting Potential for Human Health

2024-06-05T04:08:52Z

Title: Marine Fungal Diversity and its Bioprospecting Potential for Human Health Authors: Kalaiselvam, M. Abstract: Fungal biodiversity was extensively surveyed along southeast coast of India. A total of 98 species of fungi belonging to 31 genera were isolated from the mangrove soil samples, and 32 species of 12 genera under 4 families for oleaginous molds and yeasts from the mangrove root-soil. In addition, 45 species of 23 genera belonging to 4 families were documented as endophytes in the leaves of three mangroves. Also, 22 species of 15 genera under 10 families were recorded as lichenized fungi the mangrove areas. Additionally 95 species of 41 genera belonging to 5 families were identified as halophilic fungi from two different solar salterns. Predominant fungal strains were identified based on molecular techniques (18S ribosomal DNA (ITS) sequences) and the sequences have been deposited in the Genbank with accession numbers. Further, bioprospecting the fungi revealed the presence of different active bio-molecules such as citric acid from Aspergillus niger, cyclosporine A (CyA) from Fusarium oxysporum, taxol from Fusarium moliniforme, β glucan from Pleurotus florida, 5-Oxa-6-azaspiro oct-6-ene from Alternaria alternata, chitosan from endolichenic fungi, isoquercitrin from Xylaria sp., ergosterol peroxide from Fulvifimes sp., biofuel from Rhodotorula muciloginosa and antidermatophytic biomolecules from certain fungi. Above all, cultivation technique has been perfected for the production of edible mushroom, P. florida using marine waste.

Isolation and Identification of Novel Bacteria that Could Potentially Capable of Degrading Crude Oil from a Heavily Contaminated Sites in Sri Lanka

2024-06-05T04:06:40Z

Title: Isolation and Identification of Novel Bacteria that Could Potentially Capable of Degrading Crude Oil from a Heavily Contaminated Sites in Sri Lanka Authors: Manilgama, T.T.D.; Hemachandra, C.K.; Wewalwela, J.J.; Kapuruge, T.N.; Rodrigo, W.W.P.; Fonseka, W.R.K. Abstract: Bioremediation is the most harmless and efficient method for degrading petroleum hydrocarbons. The objective of the present study was to isolate and identify potential crude oil degrading bacteria from chronically contaminated sites located at Colombo and Gampaha districts of Sri Lanka. Primary enrichments were prepared by inoculating sludge and water samples separately into the Bushnell Hass Minimal Salt medium amended with 2% crude oil as the source of carbon and energy, incubated at 28 oC for 5 days at 130 rpm. Eleven bacterial isolates were obtained from spread plates prepared after fifth enrichment. The Gram’s staining showed that all the isolates were gram negative rod shape. Growth kinetics were assessed by culturing each isolate in BHMS amended with 2% crude oil under the constant culture conditions stated above with two replicates and a control. OD620 was measured in every 24 hours interval and several isolates showed excellent growth (Isolate 1, 2, 3 and 8), high growth (isolate 5), moderate growth (isolate 11, 12 and 14) and low growth (isolate 10 and 13) in respect to OD value. Partial gene sequences of 16S rRNA was shown 99% and 100% identities for Pseudomonas aeruginosa. However, the morphological variations observed in the crude oil layers and in the culture media due to the production of pigments pertaining to different isolates revealed that among the isolates, different strains of Pseudomonas aeruginosa might be present.

Impacts of Barrage Construction on Socio – Economic Status of Fishers in Thondaimanaru Lagoon, Jaffna, Sri Lanka

2024-06-05T04:02:15Z

Title: Impacts of Barrage Construction on Socio – Economic Status of Fishers in Thondaimanaru Lagoon, Jaffna, Sri Lanka Authors: Shobiya, P.; Sivashanthini, K.; Sutharshiny, S.; Gunaalan, K. Abstract: Present study was conducted to determine the impacts of barrage construction on livelihood status of fishers who involve fishing in Thondaimanaru lagoon. The data related to the socio economic condition of the fisher folk in the particular area were obtained through a pre tested structured questionnaire and in-depth guided interviews from July 2016 to January 2017. Randomly selected 25 fishermen were interviewed. The collected data were subjected to descriptive statistical analysis. Survey results indicated that 88% of fishermen are living as nuclear families consisting of 4 - 5 members. Majority of fishermen are Hindus and 92% are married. About 64% engaged in fishing are under age group of 36 - 55. Education is still not prominent among the fishers. Only 84% has primary education. The main occupation in this society is fishing and earned highest monthly income (6000 ± 1000). It was found that installation of barrage plays a crucial role in socio - economic status of fishers of Thondaimanaru lagoon, where it has severely affected the traditional employment of fishing and reduced the production of fish and hence their income. It was apparent from the present study that these fishermen have poor livelihood status and they need support from government or other organizations to enhance their socio–economic status.