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Publication Open Access Spatio-Temporal Rainfall Variability and Concentration over Sri Lanka(Hindawi, 2022-09-28) Pawar, U; Karunathilaka, P; Rathnayake, UChanges in precipitation patterns significantly affect flood and drought hazard management and water resources at local to regional scales. Therefore, the main motivation behind this paper is to examine the spatial and temporal rainfall variability over Sri Lanka by Standardized Rainfall Anomaly Index (SRAI) and Precipitation Concentration Index (PCI) from 1990 to 2019. The Mann–Kendall (MK) trend test and Sen’s slope (SS) were utilized to assess the trend in the precipitation concentration based on PCI. The Inverse Distance Weighting (IDW) interpolation method was incorporated to measure spatial distribution. Precipitation variability analysis showed that seasonal variations are more than those of annual variations. In addition, wet, normal, and dry years were identified over Sri Lanka using SRAI. The maximum SRAI (2.27) was observed for the year 2014 for the last 30 years (1990–2019), which shows the extremely wet year of Sri Lanka. The annual and seasonal PCI analysis showed moderate to irregular rainfall distribution except for the Jaffna and Ratnapura areas (annual scale-positive changes in Katugastota for 21.39% and Wellawaya for 17.6%; seasonal scale-Vavuniya for 33.64%, Trincomalee for 31.26%, and Batticaloa for 18.79% in SWMS). The MK test, SS-test, and percent change analyses reveal that rainfall distribution and concentration change do not show a significant positive or negative change in rainfall pattern in Sri Lanka, despite a few areas which experienced significant positive changes. Therefore, this study suggests that the rainfall in Sri Lanka follows the normal trend of precipitation with variations observed both annually and seasonally.Publication Open Access Spatio-Temporal Rainfall Variability and Concentration over Sri Lanka(Hindawi, 2022-09-28) Pawar, U; Karunathilaka, P; Rathnayake, UChanges in precipitation patterns significantly affect flood and drought hazard management and water resources at local to regional scales. Therefore, the main motivation behind this paper is to examine the spatial and temporal rainfall variability over Sri Lanka by Standardized Rainfall Anomaly Index (SRAI) and Precipitation Concentration Index (PCI) from 1990 to 2019. The Mann–Kendall (MK) trend test and Sen’s slope (SS) were utilized to assess the trend in the precipitation concentration based on PCI. The Inverse Distance Weighting (IDW) interpolation method was incorporated to measure spatial distribution. Precipitation variability analysis showed that seasonal variations are more than those of annual variations. In addition, wet, normal, and dry years were identified over Sri Lanka using SRAI. The maximum SRAI (2.27) was observed for the year 2014 for the last 30 years (1990–2019), which shows the extremely wet year of Sri Lanka. The annual and seasonal PCI analysis showed moderate to irregular rainfall distribution except for the Jaffna and Ratnapura areas (annual scale-positive changes in Katugastota for 21.39% and Wellawaya for 17.6%; seasonal scale-Vavuniya for 33.64%, Trincomalee for 31.26%, and Batticaloa for 18.79% in SWMS). The MK test, SS-test, and percent change analyses reveal that rainfall distribution and concentration change do not show a significant positive or negative change in rainfall pattern in Sri Lanka, despite a few areas which experienced significant positive changes. Therefore, this study suggests that the rainfall in Sri Lanka follows the normal trend of precipitation with variations observed both annually and seasonally.Publication Embargo An Efficient Root Induction Protocol for Mass Propagation of Jasminum sambac L.: (Madurai Jasmine)(Faculty of Humanities and Sciences,SLIIT, 2021-09-25) Sandamali, B. N; Kaushalya, L. M. N. M; Fonseka, D. L. C. KJasminum sambac L is an ornamental plant that produces white flowers with a very pleasant fragrance, extensively used in perfumery and religious purposes. Flowers and flower buds are used for making garlands, bouquets, hair adornments and religious offerings. Moreover flower oil used in cosmetics industry and the plant has a medicinal value. Since this plant is poorly set seeds and not respond well to other vegetative propagation methods developing a reliable propagation method for commercial production is timely important. Hence the present study was conducted to find out an efficient method for vegetative propagation of J. sambac using different concentrations (5-25 ppm ) of plant growth regulator; Indole Acetic Acid (IAA) and distilled water as control. Semi hard wood cuttings of J. sambac were used for propagation in a hydrorooting system. The experiment was arranged as a Completely Randomized Design (CRD) with nine replicates. The highest number of roots was observed in 25 ppm IAA but 15 and 20 ppm IAA did not show significant difference from 25 ppm. In all IAA treated cuttings, root initiation was observed 2 weeks after immersing in the solution where it was taken 8 weeks to initiate roots in control. The 25 ppm IAA showed the highest root length which was significantly higher than that of all other concentrations. In conclusion, 15, 20 and 25 ppm IAA concentrations were effective in inducing roots and 25 ppm IAA was effective in obtaining highest root length in semi hard wood cutting of J. sambac within 2 weeks in a hydro rooting system.