Browsing by Author "Najim, M.M.M"

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Assessment of Climate Extremes Based on SPI in WL1a Agroecological Zone - A Case Study from Kuruwita, Sri Lanka
(Sri Lanka Journal of Technology, 2020) Mendis, B.R.C.; Rasmiya Begum, S.L.; Najim, M.M.M
Drought and flood are the simple most significant climatological hazards in Sri Lanka, which primarily affects agricul tural productivity. Proper understanding and investigation of climatic extremes like drought and floods, plays a key role in planning and management of household, municipal, agricultural and industrial activities even with varied water availability. Therefore, the present study aimed to asses onset, severity and occurrence of drought and wet episodes (months) in Kuruwita region, which belongs to the Low Country Wet Zone Agro-ecological region using the Standardized Precipitation Index (SPI) at various time scales. SPI analyzed at 12 months’ time interval revealed that out of 45 years of study period (1961-2005), there were only four (1976, 1980-1981 and 1996) and six (1985-1986, 1988-1989, 2003-2004) drought and wet hydrological years, respectively. Further, the hydrological years 1981 and 2004 were identified as more affected years by drought and wet events, respectively, with relatively higher occurrence of climate extremes depicted by SPI, than normal conditions. The South-West monsoon (SWM) was found to be more prone to extreme climatic conditions, leading the Yala cropping season to become more abnormal with occurrence of more drought and wet months in Kuruwita. Therefore, the study suggests that implementation of proper mitigative measures like installation of rainwater harvesting systems, reuse or recycling of rainwater, cultivation of stress tolerant crop varieties, adaption of different cropping systems would be beneficial to minimize such adverse effects and for sustainable development in Kuruwita area
Environmental Flow Assessment–An Analysis
(Journal of Environmental Professionals Sri Lanka,, 2014) Halwatura, D.; Najim, M.M.M
Natural flow of a river is recognized as vital to sustaining riverine ecosystems. The biotic composition, structure and function of aquatic ecosystems depend largely on the hydrologic regimes; however flows of the world’s rivers are increasingly being modified through impoundments. Therefore calculation of the optimum flows for a healthier river is essential but there is no simple figure that can be given for the environmental flow requirements of rivers. Environmental flows refer to water for ecosystems. Ecosystems, however, provide a wide range of valuable services to people. Concept of the environmental flow was initiated not only to discover the river health and to manipulate river flow regimes, but also to get the maximum harvest from free flowing waters. Hence, providing for environmental flows is not exclusively a matter of sustaining ecosystems but also a matter of supporting human well being. As demand for freshwater continues to rise and ways are sought to improve water productivity, decision-making bodies at local, basin and national levels require accurate information on the role of river flows in sustaining a wide range of environmental benefits. For that reason assessment of environmental flows may contribute to setting management rules and monitoring their impact on river health.
Evaluation of Water Use in a Rice Double Cropping System in Malaysia
(Tropical Agricultural Research, 2021) Aminul, M.H.; Najim, M.M.M; Lee, T.S.
Water allocation modeling for Besut rice irrigation scheme in Malaysia
(Journal of the Agricultural Engineering Society of Sri Lanka,, 2004) Aminul Haque, M.; Lee, T.S.; Najim, M.M.M; Mohammed, T.A.