Zoology
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Item Toward Sustainable Environmental Quality: Priority Research Questions for Asia(Environmental Toxicology and Chemistry, 2021, 2021) Kenneth, M.Y.; Leung;, Katie W.Y.; Yeung;, Jing; You; Kyungho, Choi; Xiaowei, Zhang; Ross, Smith; Guang-Jie; Zhou; Mana, M.N; Yung, Carlos Arias-Barreiro; Youn-Joo An, S; Rebekah, Burket; Robert, Dwyer; Nathalie, Goodkin; Yii Siang; Hii;, Tham; Hoang;, Chris; Humphrey;, Chuleemas Boonthai; Iwai;, Seung-Woo; Jeong;, Guillaume; Juhel;, Ali; Karami;, Katerina Kyriazi; Lee;, Bin-Le; Lin; Ben, Lu; Patrick, Martin; Mae Grace; Nillos;, Katharina; Oginawati; Rathnayake, I.V.N; Risjani, Mohammad Yenny;; Shoeb;, Chin Hon; Tan; Maria Claret; Tsuchiya; Gerald T; Ankley;, Alistair; B.A; Boxall, Murray A; Rudd, Bryan W.Environmental and human health challenges are pronounced in Asia, an exceptionally diverse and complex region where influences of global megatrends are extensive and numerous stresses to environmental quality exist. ...Item Chromosomal Abnormalities in Allium cepa Induced by Treated Textile Effluents: Spatial and Temporal Variations(Journal of Toxicology, 2020) Wijeyaratne, W. M. D. N.; Wickramasinghe, P. G. M. U.Appropriate effluent treatment processes are expected to significantly reduce the toxicity of effluents before they are released to the natural environment. 0e present study was aimed to assess the spatial and temporal variations of the physical and chemical water quality parameters of a natural water body receiving treated textile effluents and to assess the chromosomal abnormalities induced by the treated textile effluents. Four sampling sites (A: effluent discharge point; B: 100m downstream from site A along the tributary; C: 200m downstream from site A along the tributary; D: 100m upstream from site A along the tributary) were selected associated to a tributary that received treated textile effluent. 0e physical and chemical water quality parameters were measured in the composite water samples collected from the study sites, and Allium cepa bioassay was conducted using aged tap water as the control. Sampling was conducted in both rainy and dry seasons. 0e conductivity, TDS, COD, and colour intensity of the water samples collected from the study sites were significantly higher during the dry season compared to those in the rainy season. Allium cepa root meristematic cells exposed to water samples from sites A, B, and C showed a significantly high interphase and prophase indices compared to those exposed to aged tap water and upstream site during both rainy and dry seasons. 0e mitotic index of the root tip cells of Allium cepa bulbs exposed to the water samples collected from the effluent discharge point (site A) and from the 100m downstream site from site A (site B) was significantly lower than that of the other sites in both rainy and dry seasons. However, the mitotic index of the root tip cells of Allium cepa bulbs exposed to the water samples from the upstream site was not significantly different from that of the control treatment during both sampling seasons. 0e bioassay indicated that the mitotic index and phase index of the root meristematic cells of Allium cepa can be affected by the treated textile effluents released to the water body and the occurrence of C metaphase, chromosomal adherence, bridges, disturbed anaphase, vagrant chromosomes, and chromosomal breaks indicated that the treated textile effluent receiving tributary can possibly contain genotoxic and mutagenic compounds which can induce chromosomal abnormalities.Item Allometric Modelling of the Stem Carbon Content of Rhizophora mucronata in a Tropical Mangrove Ecosystem(International Journal of Forestry Research, 2020) Nilmini Wijeyaratne, W. M. D.; Liyanage, P. M.Mangrove ecosystems are identified as important blue carbon ecosystems because they play an important role in carbon sequestration among the coastal ecosystems. .e present study was conducted to develop an allometric model to determine the stem carbon content of Rhizophora mucronata in a conserved tropical mangrove ecosystem. .e stepwise regression with backward elimination was used to identify the best fit model to predict the stem carbon content of Rhizophora mucronata. .e allometric equation, Ln C � −2.403 + 2.247 Ln DBH, where C: stem carbon content and DBH: diameter at breast height, was constructed to be evaluated and validated as the most suitable and practically applicable model. .e reliability of the model was 76.7%, and the model was significant at 95% level of significance. .e model bias values and the model efficiency values for the best fit model suggested that the model is suitable to be used practically. .e present study used a nondestructive method of measuring individual tree parameters to develop this allometric equation to predict the stem carbon content and it is considered as an environmentally friendly approach with minimum damage to the tree.