Browsing by Author "Jayalath, J.I.K.G."

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Background Levels of Heavy Metals in Moss Hyophila Involuta as A Bioindicator Using Four Strict Nature Reserves in Sri Lanka: Sinharaja Rainforest, Knuckles Mountain Range, Horton Plains National Park and Hakgala Mountain Forest
(Faculty of Graduate Studies, University of Kelaniya, Sri Lanka, 2016) Jayalath, J.I.K.G.; Deeyamulla, M.P.; de Silva, R.C.L.
Atmospheric deposition of six heavy metals (Zn, Cu, Pb, Ni, Cr and Cd) using the moss Hyophila involuta as a bioindicator was investigated to establish the background levels of heavy metals for different geographical and climatic zones of Sri Lanka. Moss sampling was carried out in four strict nature reserves in different geographical and climatic zones of Sri Lanka, namely Sinharaja rainforest (6°24′–6°27′ N, 80°24′–80°26′ E, 450– 500 m) from wet zone, Knuckles mountain range (7°31′ N, 80°43′ E , 1,000–1,300 m) from intermediate zone, Horton Plains National Park (6°46′–6°48′ N, 80°47′–80°49′ E, 2,000–2,200 m) and Hakgala mountain forest (6°55′ N, 80°48′ E, 1,700–1,800 m) from wet zone and Central highlands using about 10 sampling sites from each location within a month from October to November 2015. Concentrations of heavy metals in moss were analysed by using atomic absorption spectrometer. The atmospheric deposition of heavy metal concentrations in all sampling stations is given for dry weight of moss and the ranges of six elements around four strict nature reserves were 9.58– 65.68, 1.87–9.97, 1.20–10.56, 1.12–7.81, 1.20–10.60 and 0.05–0.36 μg/g for Zn, Cu, Pb, Ni Cr and Cd separately. According to the statistical analysis (one-way ANOVA , p < 0.05), accumulation of Cu, Cr and Cd in moss was not significantly change among four strict nature reserves and accumulation of Ni and Pb in moss was significantly higher around Hakgala mountain forest. Atmospheric deposition of Zn in moss was significantly higher around Knuckles mountain range area than other sampling locations. Therefore background levels of heavy metals in moss can be expressed as as 5.53 (±1.75), 7.23 (±2.11), 4.03 (±1.41), 6.61 (±2.58) and 0.17 (±0.06) μg/g for Cu, Pb, Ni, Cr and Cd respectively for the most of the geographical and climatic zones of Sri Lanka and background levels of Zn can be established as 30.62 (±8.11) and 47.42 (±12.31) μg/g for wet zone including Central highlands and intermediate zone of Sri Lanka respectively.
Moss (Barbula sp.) as a bioindicator to monitor heavy metal air pollution: Comparison of native moss and moss bag technique
(Sri Lanka Association for the Advancement of Science, 2008) Jayalath, J.I.K.G.; Deeyamulla, M.P.
Biomonitoring techniques using moss (Barbula sp.) as a bioindicator have been used to examine heavy metal deposition in local areas and around point sources. We sought to determine the efficacy of moss bag technique and native moss method against bulk deposition to determine heavy metal air pollution. Atmospheric heavy metal deposition was determined around the industrial area of Sapugaskanda which includes an oil refinery, an industrial zone and three power plants; Sedawatte which has the influence of Kalanitissa power plant and Dalugama University premises which close to the A1 road. Heavy metals (Pb, Ni, Cu, Cd and Cr) were determined by Atomic Absorption Spectroscopy (AAS) during six months of period from October 2007 to March 2008. Heavy metal concentrations measured in three sampling sites during six months of period is given in μg/g dry weight of moss sample in native moss and moss bag technique. Concentration of heavy metals in bulk collector is expressed in μg/cm2 area of the funnel. Dry weight of moss in unit area was used to bring these results into a common unit. A hypothesis was developed according to the equality of population variance of results in two methods and the corresponding significant levels (α value-probability of making a decision to reject the null hypothesis when the null hypothesis is actually true) were obtained from the F distribution table to compare native moss method and moss bag technique with bulk deposition method. The results indicate that the moss bag technique is most suitable to monitor heavy metal air pollution than the native moss method when compared with the bulk deposition method.
Moss (Barbula sp.) used as biomonitor of atmospheric heavy metal deposition: Estimation of uptake efficiencies
(Sri Lanka Association for the Advancement of Science, 2008) Jayalath, J.I.K.G.; Deeyamulla, M.P.; Senanayake, S.P.
Concentrations of Pb, Ni, Cu, Cr and Cd in two Barbula species in permeable bags (moss bag method) were compared with bulk deposition measurements of these elements at three monitoring stations; Dalugama, Biyagama and Sedawatte which can be identified as highly polluted areas in Sri Lanka. Amount of heavy metals in moss and bulk collector were determined by Atomic Absorption Spectrophotometry (AAS) during six months of period from October 2007 to March 2008. Heavy metal concentrations measured in three monitoring stations during six months period is given in μg/g dry weight of moss sample. Concentration of heavy metals in bulk collector is expressed in μg/cm2 area of the funnel. These elements showed generally significant correlations between moss and bulk deposition, and uptake efficiencies (Ex) relative to that of Pb were estimated using the formula E x (%) = K x × 100 where Kx is the slope of the K Pb regression line of element x, and KPb is the slope of the regression line of Pb in mosses vs atmospheric deposition. The uptake efficiency of heavy metals were also established for each site using another formula Esx (%) = C D×A where Esx (%) is the uptake efficiency of an element x at monitoring station s, C is the moss concentration, D is the bulk deposition and A is a “ratio constant” estimated for each monitoring station. The uptake efficiencies of heavy metals to be: Ni 50-65 %; Cu 55-70%; Cr 45-60 %; Cd 60-70% for Barbula sp.1 and Ni 65- 70%; Cu 80-90 %; Cr 30-50%; Cd 45-60% for Barbula sp.2. Therefore Ni and Cu have higher uptake efficiency towards Barbula sp.2 whereas Cr and Cd have higher uptake efficiency towards Barbula sp.1.