University of Sri Jayewardenepura: Journals & Proceedings
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Gene-wide Diversity of Two Personality-Related Genes (DRD4 and SERT) in Urban and Rural Populations of House Swallows across Sri Lanka to South Pacific Indicates a Possible Demographic Expansion or Local Selection in Rural Populations
Get PDFUrbanization-related environmental and landscape changes often negatively impact biodiversity, primarily due to habitat loss and fragmentation, forcing wildlife to migrate to new habitats. Nevertheless, urban exploiters and urban adapters seem to thrive in urban environments. Behavioral plasticity might play a role in their successful urban adaptations. However, the mechanisms of how these behavioral variations are produced and maintained at the genetic level are not well understood. Neurotransmitter-related genes DRD4 and SERT have been associated with several behaviors that might play a role in urban adaptations. House swallow superspecies complex that includes Hill swallows (H. domicola), Pacific swallows (H. tahitica), and Welcome swallows (H. neoxena), is an example of urban adapters that have increasingly been observed to be nesting on artificial structures. In this study, the genetic diversity of DRD4 (9.06 kb) and SERT (21.1 kb) genes were assessed in 12 House swallow populations in a wide geographic range from Sri Lanka to Oceanic Southeast Asia, Australia, and Fiji Islands. The proportion of heterozygote sites for each population was significantly higher (P<0.01) in urban populations for both genes. Multi-locus heterozygosity (MLH) did not show similar patterns in the SERT gene, with no significant difference. However, a significant difference could be observed in DRD4 when the Sri Lankan population was excluded from the analysis. The Hill swallow population in Sri Lanka showed extremely low heterozygosity in the DRD4 region compared to the rest of the populations, which was not evident in the SERT region. The Sri Lankan population also had the highest number of private alleles and the highest proportion of minor alleles in both genes. More rural, Queensland, and West Australia populations (for DRD4), and Queensland, West Australia New South Wales, and Tasmania populations (for SERT) showed significantly negative Tajima‘s D values indicating expansion after a bottleneck or a selective sweep. The Sri Lankan population indicated a population contraction or a balancing selection scenario with a significantly positive Tajima‘s D value in SERT. Higher genetic diversity in urban populations and negative Tajima‘s D values in rural populations might suggest a demographic expansion in the lower levels of urbanization gradient with the introduction to anthropogenic resources. However, different patterns of diversity and neutrality estimates in the two genes suggest that they may be impacted by more local evolutionary processes in the genome, like adaptation through a selective sweep or balancing selection, rather than by broader demographic changes in the populations.
Keywords: Animal behavior, Fitness indicators, Local adaptation, Personality genes, Urbanizatio
Characterization of the Vocal Repertoire of Sri Lankan Jackal (Canis aureus nariya)
Get PDFVocalization is an intriguing ecological phenomenon shown across the animal kingdom. In mammals, the structure and context of vocalization are highly variable. The Sri Lankan Jackal (Canis aureus nariya) is the only wild canid species and the third largest carnivore in the island, however, little is known about its vocalization. The objective of this study is to characterize the vocal repertoire of the Sri Lankan Jackal. Provoked and spontaneous jackal vocalizations were studied from August 2021 to May 2022 as part of a broad ecological study of the species. A playback acoustic method was used to provoke the Jackal‘s vocal response. Pre-recorded howling calls were broadcasted using a speaker in several known locations where jackals are known to occur including Athurugiriya (Western Province), Periyakamkulam (Northern Province), Sellankandal wewa (Northwestern Province) and Udawalawe National Park (Sabaragamuwa Province). Unprovoked vocalizations were studied in Mannar (Northern Province), Sigiriya (Central Province) and, Gampaha (Western Province). Complete group howls and other vocalizations were recorded at the Udawalawe National Park using an Omni-directional Microphone fitted to a parabolic reflector and a Marantz solid-state recorder. Spectrometric analyses were done using Raven Pro (v. 1.6.3) bioacoustics software. Different syllable types and vocal types were identified using the differences in duration of notes (sec), frequency (Hz), frequency modulation (Hz), and the number of emphasized harmonics. Our results suggested that the jackal vocal repertoire consisted of phrases of syllable series forming a continuum and a variety of recognizable sounds. The jackal vocalization comprised of a total of 23 syllable types forming 05 vocal types, that include the bark (n=1), whimper (n=6), whine (n=12), short-lone howl (n=4), and group yip-howl (n=3). The group-yip howl is its group vocalization as well as its major vocal type in the repertoire–forming the iconic jackal howl. Our results further indicate that the functions of their vocal repertoire may be related to re-union, territorial defense as well as reinforcing group bonds.
Keywords: Canidae, Frequency modulation, Vocal behavior, Vocal ecology, Nariya 
Dung Beetle Functional Diversity and Ecosystem Services (Resource Relocation) in Different Land Use Types in the Upper Walawe Basin Area
Get PDFConversion of forest habitat to different land uses will change the environmental quality of the altered land. Since the relationship between anthropogenic disturbance and animal diversity and ecosystem services emerged, much scientific research has been conducted on this aspect. The present study focuses on comparing dung beetles, a known biological indicator, on examining five diverse environs (large forests, forest patches, Pinus plantations (Pinus caribaea), home gardens, and tea plantations) Coprophagous beetles of the subfamily Scarabaeinae (Coleoptera: Scarabaeidae). This study examined whether dung beetles' diversity, species richness, functional groups, and ecosystem services (dung removal) vary with the habitat types. We also assumed that the intensity of anthropogenic activities varies in these habitats. The experiment was conducted for 48 hours each in five habitat types with three selected replicates per each habitat type. The Shannon-Weiner Diversity Index shows that the highest dung beetle diversity is recorded in large forest areas (2.1719). The highest species abundance (186) and richness (22) were recorded in the large forest. The lowest species abundance was recorded in tea plantations (109). The lowest species richness was recorded in pinus plantations (10). Moreover, functional group diversity is high in habitats with fewer human activities. The dominant species in large forests is Onthophagus favrei (dominancy index-2.9%). In forest patches and pinus plantations, Onthophagus amphinasus (19%) and Paracopris signatus (36.30%) appeared consecutively. In home gardens and tea plantations, the most dominant species is Onthophagus unifasiatus (26.50% and 28.40%). Habitats with anthropogenic activities have less species richness and a high dominancy index. Furthermore, dung beetle resource relocation efficiency was skewed toward forest areas. The highest dung removal percentage was recorded in forest areas (large forest-9.58% and forest patches-7.33%). The dung removal in the anthropogenic activities related to land uses was decreased as a home garden (7.17%), Pinus plantation (6.58%), and tea plantation (5.42%). Moreover, large dung beetles (body mass≥0.5 g) were only recorded in large forests and forest patches. Low diversity in tea plantations could be attributed to pesticide and fertilizer usage, as beetles are highly sensitive to these chemicals. Pinus plantations showed low rates of dung removal because resource availability in those habitats is less due to the fewer mammals. These findings indicate that replacing forests and forest areas with simplified human residential areas and agricultural systems can result in shifts towards less specialized dung beetle communities with altered proportions to other animal groups.
Keywords: Scarabaeinae, Dung removal, Species richness, Species abundance, Dominance index 
Conservation of Coastal Agriculture and Forestry–towards a Sustainable Blue Economy
Get PDFBlue economy is an economic system or sector that seeks to conserve marine and freshwater environments while using them in a sustainable way to develop economic growth and produce resources such as energy and food. In terms of the global economy, around 90 per cent of all internationally traded goods are shipped by sea, and the market value of marine and coastal resources and industries is estimated at US$3 trillion per year or about 5 per cent of global gross domestic product. Sustainable use of ocean, seas and marine resources, as set out in SDG14, lies at the center of a sustainable blue economy. Sri Lanka‘s coastline is 1,340 kilometres and approximately 33 percent of Sri Lanka's population lives in coastal areas that support diverse livelihoods, from fishing to tourism to manufacturing and modern urban services. The coastal areas often provide excellent soil and climatic conditions for agriculture, which has been practiced for thousands of years and plays an important role in the economy of coastal areas. Apart from the traditional rice based farming systems it also comprise of coastal fishing and coastal aquaculture, seaweed cultivation, coconut based cropping systems, commercial cash cropping systems and homestead farming systems. With regards to forests, mangroves, coastal forests, savannah woodlands, dry forests are present in these areas. Further, coral reefs, sea grass beds, salt marshes also play an important role in sustaining the balance as together they provide habitats for biodiversity, food, shade, medicine, products for the industry, protection of the coastline and carbon sequestration. However, these ecosystems are threatened due to numerous factors; climate change (as it induces flooding, shoreline erosion, salinity intrusion, temperature rise), due to conflicting activities such as operational in these coastal areas such as infrastructure including shoreline structures (harbors, breakwaters, tourist hotels), other tourism activities, industry etc. On the face of this, these ecosystems are often in the frontline to get depleted. The habitats are also getting modified due to the increase of toxicity from both inland and marine pollution, invasion of species. Therefore more concerted effort need to be exerted for the conservation and sustainable use of the oceans, seas and marine resources if the country wants to reap the benefits of the blue economy sustainably. As oceans are shared by many countries, actions need to be taken at country, region and even global levels in the areas of regulation, technology transfer, enhancing awareness and education. A mechanism for regular monitoring is a must and this responsibility need to be shared by all the stakeholders. It is imperative to zone the coastal areas so that complementary activities will be lumped together. It is also required to strengthen the already available international agreements between the member countries such as South Asian Seas Programme, Programmes with the International Maritime Organisations, IORA (Indian Ocean Rim Association), BIMSTECH in arriving at regional policies and action plans and implementation of same with proper monitoring. The quantification of the resource is a vital step. It is also important to operationalize the Coastal Zone Management Plans in existence and declare Special Area Management Sites to ensure conservation and sustainable use of these resources.
Keywords: Coastal agriculture, Forestry, Blue economy, Sustainable development goals, Management plans 
Study of BOD: COD Ratio as an Indicator for Wastewater of Rubber Industry Sector
Get PDFWhen considering the rubber industry sector, the most significant challenge is the efficient wastewater treatment before discharging it into the natural environment. The rubber industry is considered to be highly chemical and water-intensive: and involves enormous quantitative s of waste production. The ratio between Biological Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) is a widely used parameter in characterising wastewater and then the same was used in this study as an indication to measure the efficiency of wastewater treatment plant operated in the rubber industry sector. Data for the study was extracted from samples collected from 10 wastewater treatment plants of rubber industries in the Sabaragamuwa Province; two samples from each representing before and after treatment. The samples were tested in two replicated for BOD5, COD, pH, and conductivity. These selected rubber factories contain lagoon/pond type wastewater treatment systems or activated sludge wastewater treatment systems. The results showed that the treated wastewater samples were within the range of 0.1–0.4 of BOD5: COD and were below the BOD5: COD permissible level as per CEA standards. (General standards for rubber in inland surface waters; Latex-BOD 60, COD 400; Lanka rubber/crepe rubber–BOD 50, COD 400) comparing the BOD, COD, pH, and conductivity influent and effluent of the treatment process proves the effectiveness of each treatment plant of the relevant industry. Tested samples show a high BOD5: COD ratio in influent and effluent of wastewater treatment system indicate that wastewater of the industry is easily biodegradable. However, more research comparing the characteristics of different rubber manufacturing processes is needed to develop this approach further.
Keywords: BOD, COD, BOD: COD ratio, Wastewater treatment plant 
Life Cycle Assessment of Conventionally and Organically Grown Pineapple in Gampaha District
Get PDFPineapple is one of the major commercial fruits grown in Gampaha and Kurunegala districts of Sri Lanka. Most cultivations are under conventional practices which generate significant environmental impacts while there are few organic cultivations (~1%). There is lack of published on the environmental impacts related to cultivation of pineapple in Sri Lanka. This study therefore aimed to quantify and compare environmental impacts of conventionally and organically grown pineapple in Gampaha District. Environmental impacts were compared using Life Cycle Assessment (LCA) tool which evaluates the potential environmental impacts throughout the life cycle of a product or a process. According to ISO 14040:2006 and ISO 14044:2006 guidelines, LCA methodology has four main phases such as goal and scope definition, life cycle inventory analysis (LCI), life cycle impact assessment (LCIA), and life cycle interpretation. The system boundary for the study was from cradle to farm gate. All the environmental impacts were estimated for a functional unit of one tonne of pineapple. Primary data for the LCA was gathered using a pre-tested structured questionnaire conducted among twenty conventional- and six organic farms. Input and output inventories were prepared during LCI phase. Under LCIA phase, impact categories such as global warming potential (GWP), eutrophication, human toxicity, terrestrial ecotoxicity, and freshwater ecotoxicity were considered. Results indicated that conventional cultivation system has significantly higher impacts compared to the organic cultivation system. Global warming potential of conventionally cultivated one tonne of pineapple was 182.23 kg CO2 eq. It was 26.72 kg CO2 eq for organic cultivation indicating 7 times lower impact. Eutrophication potential was 6.63 kg PO43- eq for conventional cultivation while that for organic cultivation was 0.81 kg PO43- eq (8 times lower). Pesticide use has resulted in 2,279.12 kg 1,4 DB eq of human toxicity, 18,331.71 kg 1,4 DB eq of freshwater ecotoxicity and 1,624,494.37 kg 1,4 DB eq terrestrial ecotoxicity for conventional cultivation while organic cultivations have resulted in no toxicity. The results highlight significant contribution of synthetic fertilizers and pesticides towards all five impact categories of the LCA. The results could provide implications for promoting organic cultivation in order to reduce the impacts on the environment in the long run.
Keywords: Life cycle assessment, Pineapple, Conventional cultivation, Organic cultivation, Environmental impacts 
Influence of Biochar on Plant Uptake of Personal Care Products: Caffeine and Triclosan
Get PDFThe use of personal care products (PCPs) extends a person's longevity. Nonetheless, because of its uncontrolled burden on the environment, it is regarded as an emerging contaminant. The goal of this research is to determine the influence of cinnamon wood biochar (CWBC) on plant uptake of caffeine (CFN) and triclosan (TRI) from the soil. Ipomeoa aquatica was cultivated for 4 weeks in soil with a 2.5% CWBC amendment and spiked with 100 mg/kg CFN and 200 mg/kg TRI. Ultra- High-performance liquid chromatography (UHPLC) was used to quantify the CFN and TRI in the plant. The surface morphology of CWBC was investigated by scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) surface area. The gasification of biomass which increased the CWBC's surface area to 589 m2/g, due to the development of a porous structure. The CFN accumulated more in the shoot of the plant whereas TRI accumulated in the root. The addition of 2.5% CWBC significantly (p<0.05) decreased the root and shoot accumulation of CFN by 40.4% and 70.9%, whilst those for TRI by 38.9% and 19.9%, respectively. The relative bioconcentration factors (RBF) of CFN and TRI in shoot and root was calculated by the ratio of bioconcentration factor (BCF) using RBF=〖BCF(CWBC amended soil)⁄〖BCF_soil and the results suggested that the addition of 2.5% CWBC decrease the RBF below the one indicating the effectiveness of CWBC towards mitigating the plant uptake of PCPs. Overall, the present study suggested the application of biochar to soil significantly decreased the plant uptake of PCPs, thus, can reduce the potential risk caused by the unintentional consumption of contaminated vegetables.
Keywords: Personal Care Products, Soil amendment, Health risk, Plant uptake 
Influence of Environmental Factors in Determining Tourist Destinations
Get PDFTourism is a growing industry in many countries of the world and for many countries it is a potential source of economic growth and employment opportunities. Focusing on Sri Lanka in terms of tourism, tourism is the third largest foreign exchange earner in Sri Lanka. It is important to correctly identify the internal tourist destinations in Sri Lanka, as well as the environmental factors that influence those destinations' decisions, so that development projects can be made. Accordingly, through this study, the environmental factor has been studied in determining the tourist destinations. The three places chosen as the study area of this research are Sinharaja Rainforest in Kalawana Divisional Secretariat Division of Ratnapura District of Sri Lanka, Bopath Ella Waterfall located in Kuruvita Divisional Secretariat Division and Sitawaka Botanical Garden located in Seethawaka Divisional Secretariat Division of Colombo District. The judgment-based method was used to select the three tourist destinations. Also, 120 people were used as a sample for data collection. A simple random sampling method was used. Primary data and secondary data were used for this study. Participant observation, interview method and questionnaire method were used to collect primary data. IBM SPSS-26 version software was used for data analysis and a Binary Logistic model was used to identify how much influence the environmental factor has in determining tourist destinations. Accordingly, it was studied here whether the environmental factor affecting the decision of a tourist destination changes according to variables such as age, gender, marital Status, education level, occupation, income level etc. According to the results of the research, the Chi- square value is 56.435. The P value is statistically significant at the 1% level. That means the P value of the model is 0.000 (P<0.01). That means that the model is statistically significant. That is, according to the independent variables used above, it can be concluded that there is a change in the influence of the environmental factor to determine a tourist destination. In the analysis, the statistical significance of each independent variable was tested by the Wald test, which can identify the effect of each independent variable on the model. Accordingly, it was clear from this research that the variables of profession and education have a significant effect on the environmental factor that affects the decision of a tourist destination.
Keywords: Education, Environmental factor, Profession, Tourist destinations 
Studies on Bamboo Dendrocalamus asper Seed Viability Changes with the Storage Age in Sri Lanka
Get PDFDendrocalamus asper is an introduced bamboo species grown in wet/intermediate climatic areas of Sri Lanka. It has many uses in both economic, environmental contexts. Propagation through seeds is well adapted practice among medium to large scale groves. The Sowing medium plays an important role in the production of good quality seedlings. Therefore, this study aims to determine the best nursery media for seed germination and evaluate the performance of seeds yearly which were kept in a refrigerator (4o C) from 2018 to 2023. Seven sowing media (Treatments) were set up as river sand alone, river sand+topsoil (1:1), river sand+coir dust (1:1), compost only, topsoil only, coir dust only, and river sand+compost (1:1) as the first experiment in 2018 to determine the best sowing media for seed germination. Germination pots were set up in a completely randomized design (CRD) with twenty replicates using 10 seeds per each treatment. Germination percentages were recorded in 12, 15 and 18 days after seed sowing. Treatment differences were tested by ANOVA and significant means were separated using the Duncan multiple range test. The results reviled that treatment with river sand with topsoil (1:1) and Treatment only with river sand were shown best media for seed germination. The corresponding values were 40.98%, 44.29%, and 47.97% for river sand with topsoil (1:1) and 38.74%, 39.84%, 44.11% for medium with river sand only. Thereafter best sowing media treatment with river sand with topsoil (1:1) were used to test the seeds germination percentage using cool stored (4o C) seeds in year 2019, 2020, 2021, 2022 and 2023 and the figures were reported descriptively after 12, 15 and 18 after sowing. Average seed germination percentage 18 days after seed sowing dropped to 45.10% in 2019. The germination percentages for 2020 were 37.1%, 40.20%, and 41.5%, in that order. The experiment was conducted again in 2021, with germination rates of 35.40%, 36.90%, and 37.90%. It was 34.22%, 35.22%, and 36% in 2022, respectively. Although 36% germination was recorded at the end of 15 days, only 21% survived at the end. Rest of the plants were died due to the poor vigor and poor performance of seeds. After 18 days, the experiment conducted in 2023 showed that 17.50% of the seeds had germinated. The research findings showed that seed viability of (Dendrocalamus asper) has gradually declined with time in Sri Lanka.
Keywords: Bamboo, Dendrocalamus asper, Germination percentage, Sowing media, Viabilit
A Preliminary Study on Sri Lankan Impatiens: Phylogenetics and Morphological Evidences
No full textGenus Impatians (Family Balsaminaceae) having 23 native species in Sri Lanka, displays a high endemicity of nearly 70%. The objectives of the present study were to assess the phylogenetic placement of Sri Lankan Impatiens and to elucidate the morphological characters supporting their relationships. Based on the sequence availability, Internal Transcribed Spacer (ITS) region was used for a total of 57 species, including seven Sri Lankan Impatiens species. Maximum likelihood and neighbour joining analysis were performed to produce the phylogenetic trees using Hydrocera triflora as the outgroup. Selected morphological characters were obtained using published literature and herbarium records with special emphasis on floral characteristics to produce the cladogram. Analysis was conducted using R 4.2.2 version. Likelihood and neighbour joining analysis produced congruent phylogenetic trees. Results revealed that, Sri Lankan Impatiens taxa forms a monophyletic separate cluster revealing their phylogenetic distinctiveness. Sri Lankan group show a close relationship with Impatiens native to China and India providing insights to their biogeographic affinities. Furthermore, morphological data supported the relationships derived from molecular phylogenetic analysis. Two distinct species clusters were identified in both the phylogram and cladogram; I. henslowiana and I. grandis constituted one cluster, while I. leptopoda and I. flaccida comprised the other. These preliminary results provide baseline information to investigate character evolution, floral adaptations, more resolved phylogeny, and biogeography of old-world Impatiens species.
Keywords: Impatiens, Phylogeny, ITS, Morpholog