University of Sri Jayewardenepura: Journals & Proceedings
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Application of Multispectral Drone for Quantitative Assessment of the Fertilizer Requirement for the Up-country Tea Plantation in Sri Lanka
Get PDFThe amount of chlorophyll content and structure would differ between diseased and healthy plants, affecting the NDVI values, which strongly correlated with fertilizer applications. The primary goal of this research is to use a multispectral drone to quantify the fertilizer requirements for the sample tea plantations in Nuwara Eliya, Sri Lanka. In contrast, a drone with multispectral imaging camera sensors was used to gather images covering blue, green, red, red-edge, and near-infrared bands. The collected images were analyzed, and geographic outputs were generated. The processed geospatial data were used to determine the NDVI values for each tea field, and the general health of the tea was estimated. Finally, NDVI readings and geospatial products from each tea field related to soil analytical data. Based on the NDVI values, 25 selected soil samples were collected using sampling plots. The concentrations of pH, electrical conductivity (EC), nitrogen (N), phosphorus (P) and potassium (K) were then determined using standard soil testing procedures. Finally, soil analysis results were combined with the geospatial data. In addition, the amount of Dolomite for each tea field was calculated based on the pH values, and the amount of nitrogen, phosphorus, and potassium was calculated as yield and area and based on the number of tea bushes. The tea plantations show an NDVI range of 0.76-0.81 for low healthy tea, 0.81-0.86 for medium healthy tea and 0.86-0.97 for healthy tea. The healthiness percentages of one of the tea plantation show 18% healthy tea, 54% medium healthy tea, and 22% low healthy tea. Conversely, the healthiness percentages of the other tea plantation show 44% healthy tea, 39% medium healthy tea and 17% low healthy tea based on the NDVI value. The average value of pH, EC, N, P, and K are 4.84, 41.58, 0.29, 0.11, 0.04 in tea plantations, respectively, and in other planation, average values of pH, EC, N%, P%, and K% are 4.83, 40.96, 0.36, 0.25, 0.04 respectively. The amounts of Dolomite for each tea field are 2685.32 Kg/ha and 977.34 Kg/ha. In one tea field, an average annual NPK fertilizer need is 685 kg per hectare, 94 kg per hectare, and 269 kg per hectare, respectively. Additionally, calculations based on tea bushes indicate that the average annual NPK fertilizer requirements are 685 kg, 89 kg, and 254 kg, respectively. Other tea filed average annual NPK fertilizer need is 88 kg per hectare, 24 kg per hectare, and 68 kg per hectare, respectively. Additionally, calculations based on tea bushes indicate that the average annual NPK fertilizer requirements are 90 kg, 25 kg, and 70 kg, respectively. However, these values have several limitations, such as climate, soil, plant, and cultural practices. This study mainly focuses on and creates Insights into Plant Health by assessing precise plant-level data using a multispectral imaging system. It had not been correlated with other factors except soil conditions.
Keywords: Unmanned aerial vehicles, Multispectral, NDVI, Tea, Fertilize
Release of Potassium Ions from Feldspar by Organic Acids Present in Potassium-Solubilizing Bacteria
Get PDFAgricultural production and quality are determined by the nutrient levels in the soil. Permanent agricultural lands are usually nutrient deficient and it is compensated by fertilization. Recent studies have found that potassium-bearing chemical fertilizers caused some environmental issues and these fertilizers are expensive. Therefore, the development of a new method for supplying potassium to plants using ingredients found in Sri Lanka is important. In this respect, the bioconversion of feldspar using biotechnological processing to obtain potassium fertilizers is very promising. The overall objective of this study is to explore the release of potassium ions from feldspar (Microcline- KAlSi3O8) found in Sri Lanka by organic acids present in potassium-solubilizing bacteria to improve the efficiency of these minerals to use in more sustainable agricultural practices. In this research, the solubilization of feldspar with citric, oxalic, succinic, and tartaric acids (the main acids that are produced by potassium solubilizing bacteria) was studied, concerning the effect of acid type, the effect of each acid concentration, the effect of particle size of feldspar, the effect of incubation time, and the changes in pH over time. Ground feldspar (0.150–0.300 mm and 0.075– 0.150 mm) was separately shaken with 0.01, 0.02, 0.03, 0.04 and 0.05 M of each organic acid for different periods (1, 2.5 and 4 hours) and the released potassium ion concentration was measured using a flame photometer and pH change was measured using a pH meter. The extent of solubilization of feldspar was shown to be influenced by the type of organic acid used. In comparison to inorganic acids (H2SO4), some organic acids were more successful in solubilizing feldspar. Both oxalic and tartaric acids showed a higher capability of releasing potassium from the feldspar than other acids by up to 9 folds. The solubilization was insignificant for the same acid when the acid concentration was changed. The solubility of feldspar in all acids increased as the particle size decreased. The solubilization of feldspar was increased practically in almost all acids as time increased. pH was increased in almost all acids when the reaction time was increased. These findings show that both oxalic and tartaric acids are the most successful acids in solubilizing feldspar. Finding bacteria that secrete these acids as their major byproducts and conditions that secrete these acids would be beneficial for agriculture and feldspar can be used to supply potassium to agricultural lands.
Keywords: Organic acids, Feldspar, Solubilization 
Connecting the Dots; Environmental Literacy Index in Measuring Knowledge for Environmental Conservation
Get PDFConservationist Aldo Leopold noted that acts of conservation without the requisite desires and skill are futile. Systematic environmental education plays a significant role in enhancing knowledge and competencies for environmental sustainability through a scientifically informed citizenry. The environmental education spiral consists of three key elements; environmental awareness, environmental conduct, and environmental literacy. While environmental conduct that emerged with awareness contributes to the reduction of environmental degradation, scholars argue that environmental literacy contributes to conservation. With the objective of developing an environmental literacy index, this research assessed environmental knowledge, personal conduct, and the extent of application of environmental knowledge. Key informant interviews were held to develop the index with 30 criteria, and a survey was held with 160 students in schools and universities, teachers, and development officers. Environmental literacy is seen as the individual‘s understanding and competencies that create rational and informed decisions and contributions to conserve natural systems and associated communities that create a sustainable and environmentally friendly quality of life. Environmental education can take place in many forms and is incorporated in the school education syllabus from grade one to eleven in general, and in the science stream. Among the school students, the majority (76%) were able to identify and understand age- appropriate environmental features and significance, however, had very low (13%) personal conduct for reducing pressure on the environment, while had moderate (38%) literacy levels. The average responses of the university students were 82%, 48% and 63%. Teachers, including non- science subjects teaching, had a similar status with the university students, indicating 84%, 54%, and 61%. The development officers showed slightly different patterns, representing 73%, 41% and 51%. Among all the respondents, only 13% identified agriculture practices may contribute to water pollution, 12% stated that the transport sector contributes to greenhouse gas emissions, and 9% believed that energy practices at home contribute to global warming. The study reveals that environmental understanding has not contributed much to personal behaviours to reduce the pressure on the environment, and environmental literacy has not been in a state of environmental activism.
Keywords: Environmental conservation, Environmental education, Environmental literacy 
Phytochemical Analysis of Some Selected Indigenous Plants in Eastern Region of Sri Lanka used for Minimizing Insect Damage on Stored Grains during Storage
Get PDFGrains are precious food in developing countries but are tragically susceptible to attack by several stored insects. Thus, grain productions often fall below demand. As the resistance of pests against synthetic chemical pesticides and residues in foods increased, consumers‘ awareness turned toward food and environmental safety. The studies conducted in Sri Lanka revealed that the botanical pesticides are being used to minimize these problems and have the potential to battle against pests on stored grains during storage. Further the reference in Sri Lanka evidenced that the botanical pesticides are readily available, inexpensive, easily biodegradable and low toxic to non-target organisms. With this concept the present study has been undertaken to analyze the secondary metabolites, known as phytochemicals that possess antioxidant or anti insecticidal properties, which are much safe, eco-friendly and can combat with the man-made chemicals in controlling the storage pests. The study was carried out to find the presence of phytochemicals namely, alkaloid, flavonoid, phenol, tannin, steroids, cardiac glycosides, terpenoid, saponine and reducing sugars in an aqueous extract of some selected indigenous plants, which are available in Eastern Region of Sri Lanka namely; Capsicum annuum (Chilli), Citrus aurantiifolia (Lime) Piper nigrum (Pepper), Azadiracta indica (Neem), Moringa oleifera (Moringa) Eucalyptus globules (Eucalyptus), Justicia adhatoda (Adhathodai) Annona reticulate (Annona), Cymbopogan citratus (Lemon grass) Vitex trifolia (Nochchi), Ocimum tenuiflorium (Thulsi), Lantenna camera(Nayunni), Eichhornia crassipes (Water hayasinth), Tagetes erecta (Marigold) piper longum (Thipilli) and Achyranthes aspera (Nayuruvi), that have pesticidal properties. The leaves of selected crops were dried at room temperature for a period of one week and grounded in to fine powder to take 10 g of powder from each to prepare 200 ml of water extract using electro thermal soxhlet for 36 hours and analyses qualitatively by the standard scientific procedures. The results showed that the water extract of Neem, Moringa and Thulsi contained all the above tested phytochemicals. The flavonoid was observed in all tested crops except Thipilil, which contained only phenol and tannin. Further Pepper, Eucalyptus, Lemon grass, Annona, and Chilli did not show alkaloids where Annona had only flavonoid, phenol and tannin. Nochchi showed all the phytochemicals except cardiac glycosides and terpenoid. The study confirmed the strength of tested crops in utilizing them in the pest management programme at storage because of the presence of one or more groups of the major insecticidal components like, alkaloids and flavonoids. The study also exposes the way for further studies related to the impact of individual plant insecticidal components against storage pests.
Keywords: Aalkaloids, Aqueous, Extract, Grains and phytochemical 
Mangrove Biodiversity Conservation and Aquaculture Practices in Sri Lanka: An Overview
Get PDFThe tropical island of Sri Lanka is endowed with a diverse and resourceful coastal area of 1,700 km coastline and 152,000 ha of highly productive 82 lagoons and 93,075ha of 45 estuary ecosystems. Around 33% of the population in coastal areas is engaged in fishing as the main income source, which contributes to around 1.10% of the national GDP. The objective of the review was to provide an overview of the present status of Sri Lankan coastal aquaculture, mangrove coverage, and conservation status. Mangroves are ecologically and economically important ecosystems providing the best nursery grounds for both blackish and marine species, covering only 0.24% of Sri Lanka‘s total land area. In addition, as the most carbon-rich forests in the tropics, mangroves provide a wide range of ecosystem services and biodiversity conservation. Currently, Sri Lankan mangroves are estimated to cover 160 km2 and are distributed mainly in Jaffna, Kalpitiya, Batticaloa, Rekawa, and Trincomalee. Including endangered species such as Sonneratia apetala, Ceriops decandra, and Lumnitzera littorea, there are 21 true mangrove species, and 24 mangrove associate species can be found. However, mangrove ecosystems in Sri Lanka are progressively under threat due to coastal aquaculture practices, especially shrimp farming and development projects. Human settlements, overexploitation, and climatic variables such as coastal flooding, drought, rainfall, salinity changes, increased sea level, and sea surface temperature have significantly influenced coastal aquaculture and substantially damage the mangroves resulting in loss of mangrove biodiversity. Between 1980 and 2005, approximately 25% of mangrove habitats are estimated to have been destroyed. Recently, 1,000-1,200 hectares of mangroves have been established in 23 wetlands in Sri Lanka becoming leader of the mangrove conservation in Commonwealth countries. In conclusion, it is imperative to apply international standards for mangrove-based aquacultural practices, mangrove rehabilitation, and technical and management interventions.
Keywords: Biodiversity, Coastal aquaculture, Coastal ecosystems, Mangroves 
Cassava Flour as a Possible Replacement for Wheat Flour: A Comprehensive Review Considering the Sri Lankan Scenario
Get PDFCassava (Manihot esculenta) is a long tuberous starch-containing root crop that stands as a significant staple food globally. Its adaptability to various climates has increased its commercial growth. However, challenges such as toxic cyanogenic glucosides and rapid perishability in cassava demand its processing for safety and extended shelf-life. In Sri Lanka, where cassava is widely consumed, surplus production can be a highly prospective revenue. This review summarizes the utilization of cassava flour as a potential alternative for wheat flour emphasizing the Sri Lankan scenario. The cassava flour production process involves cleaning, peeling, slicing, drying, grinding, and sieving. Nutritional composition varies among cultivars, with variations in starch, amylase, fiber, protein, and ash. The cyanogenic levels also depend on the cultivars. Cassava flour emerges as a promising wheat flour substitute due to its abundance, effortless cultivation practices, nutritional profile, and unique functional properties. Furthermore, cassava flour is gluten-free and considered as the most comparable gluten-free substitute to wheat flour in terms of texture and taste. The incorporation of cassava flour into bakery products shows an opportunity to reduce the massive dependence on costly wheat flour imports in developing countries, which improves the country’s revenues. This review focuses on diverse food applications of cassava flour, including cookies rackers, biscuits, and commercial products, highlighting cassava flour's market potential in Sri Lanka amidst the increasing demand for gluten-free products.Keywords: Cassava Flour, Wheat Flour, Substitute, Sri Lanka, Food Product
Clinical challenges in cutaneous leishmaniasis: A cohort from Southern Province, Sri Lanka
Get PDFSouthern Province of Sri Lanka is endemic to cutaneous leishmaniasis (CL). This study aims to describe the clinico-demographic profile of a cohort of CL patients (n=115, CL confirmed by PCR), reported at two main hospitals in the Matara and Hambantota districts of the Southern Province, highlighting the novel clinical presentations and possible challenges and/or favourable findings in the elimination of CL from the Province, along with a comparison with the provincial literature (Quality-checked publications of similar data) to identify possible disease trends, which could be useful in planning control programmes. We have found that CL is common in young males, and typically appears as single nodules in the upper limb. These nodules often contain high parasite loads. Our observations show that ulceration of papules and plaques is a new development in the province. This could have significant implications for differential diagnosis and chronicity. One positive trend we have observed is the early seeking of treatment, which had improved diagnostic rates. Additionally, there has been an increase in reporting of papules, which were silent reservoirs of CL. This indicates an increased awareness of the disease among patients in this cohort. However, several negative trends were identified as well. The Tangalle divisional secretariat division has emerged as a possible new disease focus. Furthermore, the high number of nodules and lesions with high parasite loads, which are likely to be less responsive to treatment, could pose challenges for CL elimination. It is important to note that these findings are based on a limited sample size and should be further investigated with a larger sample to gain more comprehensive understanding of the situation.
KEYWORDS: Cutaneous leishmaniasis, Southern Province, Sri Lanka, clinical, demographic, Leishmania donovani
 
Return to Reading: An appeal to reconsider the pedagogy of Teaching English as a Second Language in Sri Lanka
Get PDFThis paper calls for a rethinking about the pedagogy of teaching English in Sri Lanka and suggests an alternate and effectively possible way through getting students to read for pleasure. In answering the question as to how we can bring in an impactful, low-cost solution – as other ways seem difficult in this country at the moment - to improving the teaching/learning of English in Sri Lanka, this paper hopes to show, through research done in this area by Second Language Acquisition theorists, that reading for pleasure especially at young ages, but also among adult learners, is a practically possible and suitable solution to this country, which has a strong public library system in place. Therefore, the focus is mainly on the necessity and the worth of such a programme to university students - the tertiary education sector being where the researcher is mainly involved in - and will bring in the ideas of SLA theorists, mainly Stephen D. Krashen, to advocate a particular pedagogy. Therefore, the paper will limit itself to showing why such a programme is necessary and how it can be put in place, using the work that has been done so far in this field through the English for Fun project, centered at the University of Sri Jayewardenepura and taken across the country through the National Library and the public libraries under its purview. The idea is to demonstrate the actual possibilities that arise when educational systems and the national library system work together, to put parallel and even alternate ways of teaching in place in this field that is crying out for innovation.
KEYWORDS: TESL, Reading, Poverty, Pleasure, Libraries
 
A COMPARATIVE STUDY OF DETERMINATIONS OF RESERVATION WAGE EXPECTATIONS AMONG UNEMPLOYED MEN AND WOMEN IN SRI LANKA
Get PDFThe "reservation wage" concept indicates the minimum compensation a person is willing to accept when seeking employment. This study aims to determine how reservation wage expectations differ between unemployed men and women in Sri Lanka. This analysis used secondary data extracted from the Sri Lanka Labour Force Survey (2021), which was conducted by the Department of Census and Statistics, and encompasses a sample size of 1,567 total unemployed, comprising 739 unemployed males and 828 unemployed females. A semi-log model was applied separately to the unemployed men, the unemployed women and the total unemployed to achieve the study's objective. The results indicated that gender significantly influences reservation wage expectations among unemployed men and women. Compared with women, unemployed men have a higher reservation wage expectation. Noteworthy variables, including household size, age, and unemployment duration, exhibit varying degrees of insignificance in shaping reservation wage expectations for both genders. Finally, this study concluded that the reservation wage expectations among unemployed men and women in Sri Lanka are significantly affected by various demographic, household socio-economic and regional geographical factors. This study provides valuable insights for policymakers to foster gender equality and labour market inclusivity to reduce the gender gap in Sri Lanka
Investigation of the Structure of the Complex Oligomeric Mixture Formed During Grignard Tetramethylation of N-benzylphthalimide
Get PDFTMIO or 1,1,3,3-tetramethylisoindolin-2-yloxyl (5, Scheme 1) is one of the most versatile isoindoline nitroxides due to its applications [1, 2] and a variety of important advantages such as thermal stability, low reactivity towards olefins [3], symmetrical nature [4], UV detectability [5] and relative inertness to free radical attack [4][4]. The most common and effective pathway for synthesizing 5 remains the Grignard-based approach in which N-benzylphthalimide 1 is treated with methylmagnesium halide in refluxing toluene, followed by subsequent debenzylation and oxidation of the resulting secondary amin