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Jalaldeen Mohamed Harris Periyathamby Vinobab Ranil Kavindra Asela Kularatne Champika Ellawala Kankanamge 《环境科学学报(英文版)》2016,28(9):211-218
The necessity to understand the relationship between cyanobacterial species abundance and water quality variations in coastal lagoons is crucial to develop strategies to prevent further cyanobacterial proliferation. This paper evaluates the relationship between water quality variations on the distribution of cyanobacteria during a 12-month period in Batticaloa Lagoon (Sri Lanka) using Redundancy analysis and Pearson correlations. Drastic variations in pH, temperature, salinity, dissolved oxygen (DO) and total phosphorus (TP) levels were reported, but not turbidity and NO3−. This brackish waterbody is hypereutrophic (TP levels > 0.1 mg/L). The cyanobacterial community contained 13 genera and 22 species. NO3−, TP and turbidity levels positively influenced cyanobacterial abundance during all seasons indicating that nutrient (largely phosphorus) and sediment entry control is highly crucial along with periodic monitoring of cyanobacterial growth. 相似文献
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Influence of tropical seasonal variations on landfill leachate characteristics--results from lysimeter studies 总被引:2,自引:0,他引:2
Tränkler J Visvanathan C Kuruparan P Tubtimthai O 《Waste management (New York, N.Y.)》2005,25(10):1013-1020
Considering the quality of design and construction of landfills in developing countries, little information can be derived from randomly taken leachate samples. Leachate generation and composition under monsoon conditions have been studied using lysimeters to simulate sanitary landfills and open cell settings. In this study, lysimeters were filled with domestic waste, highly organic market waste and pre-treated waste. Results over two subsequent dry and rainy seasons indicate that the open cell lysimeter simulation showed the highest leachate generation throughout the rainy season, with leachate flow in all lysimeters coming to a halt during the dry periods. More than 60% of the precipitation was found in the form of leachate. The specific COD and TKN load discharged from the open cell was 20% and 180% more than that of the sanitary landfill lysimeters. Types of waste material and kind of pre-treatment prior to landfilling strongly influenced the pollutant load. Compared to the sanitary landfill lysimeter filled with domestic waste, the specific COD and TKN load discharged from the pre-treated waste lysimeter accounted for only 4% and 16%, respectively. Considering the local settings of tropical landfills, these results suggest that landfill design and operation has to be adjusted. Leachate can be collected and stored during the rainy season, and recirculation of leachate is recommended to maintain a steady and even accelerated degradation during the prolonged dry season. The open cell approach in combination with leachate recirculation is suggested as an option for interim landfill operations. 相似文献
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Rajendram Thivyatharsan H. A. Y. R. Gunarathna Benedict Francis Antony Basnayake Periyathamby Kuruparan 《Journal of Material Cycles and Waste Management》2012,14(1):27-37
The objective of the study was to develop a low cost and environmentally friendly liner system for a landfill bioreactor to
harness energy from waste. The landfill bioreactor test cell was constructed and evaluated for performance under dry tropical
conditions of Sri Lanka. The research was carried out from March 2009 to September 2010. The clay-waste polyethylene-clay
composite liner system was developed and permeability was tested. The permeability values of the liner under both saturated
and unsaturated conditions at the high estimated hydraulic head of 86.2 cm were in between 6.3 × 10−8 and 2.6 × 10−8 cm/s. The permeability of the liner under waste filled condition varied between 2.17 × 10−9 and 8.15 × 10−9 cm/s, which satisfies the standard permeability value. Thus, the results were below the minimum requirement at very high
estimated leachate head. After loading the test cell, leachate and permeate characteristics were analyzed for 273 days, from
January 2010 to September 2010. The study showed the relationships among various parameters including pH, electrical permeability,
chemical oxygen demand, biological oxygen demand, ammonia, nitrate, phosphate, total solids, volatile solids, total suspended
solids and volatile suspended solids. The results of the analysis indicated that there are significant differences in the
values of leachate and permeate parameters. The permeate parameters had values very much lower than those of leachate. It
reveals that the clay-waste polyethylene-clay composite liner system reduced the concentration of these parameters when the
leachate passed through the liner. The biofilm formed in waste polyethylene within the liner may have degraded most of organic
materials found in the leachate when it passed through the liner. Therefore, the clay-waste polyethylene-clay composite liner
system can be applied for full scale landfill bioreactors, particularly for Asian developing countries, due to better performance
and more environmentally friendly characteristics. 相似文献
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