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231.
232.
The pollution of the marine environment caused by land-based sources threatens or impairs the health of the ecosystems and the value of human uses of the coastal waters. the Contracting Parties to the Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region agreed to take all appropriate measures to prevent, reduce and control pollution. in the first meeting of the Contracting Parties, the development of a protocol on the control of marine pollution from land-based sources was recommended as a measure to protect the marine environment.
A small group of experts from the Caribbean Region formulated a strategy for controlling land-based sources of marine pollution. Due to the diverse nature, resources and capabilities of the countries comprising the Region, the pollution control strategy suggested by the group of experts included the following techniques or their most appropriate combination: (1) pollution prevention measures, (2) effluent limitations, (3) water quality limitations, (4) environmental planning, and (5) best management practices. the desirable control strategy should be based on a system of discharge permits in the case of point source pollution, which includes effluent and water quality limitations. the technology based effluent limitations could be applied as a short-range strategy to control pollution from industrial and domestic point source discharges. the use of water quality standards could become part of a long-range strategy for controlling point sources. for nonpoint sources, it would be virtually impossible to develop effluent limitations. Thus, the implementation of best management practices and effective environmental planning would be the most reasonable control strategy for non-point sources. However, pollution prevention measures could consist of a “black list” of substances that should be completely banned, and a “grey list” for those that should be strictly limited. These lists should be adopted or appropriately modified for the conditions of the Wider Caribbean Region.
The development of control based on the water quality of the receiving body of water involves the collection and analysis of effluent and ambient data to develop water quality based permit limits and to assess compliance with these permits. Finally, any marine pollution control strategy developed by the countries of the Region should be mutually agreed upon and implemented within a period of ten years from the ratification of a protocol on land-based sources of marine pollution. 相似文献
A small group of experts from the Caribbean Region formulated a strategy for controlling land-based sources of marine pollution. Due to the diverse nature, resources and capabilities of the countries comprising the Region, the pollution control strategy suggested by the group of experts included the following techniques or their most appropriate combination: (1) pollution prevention measures, (2) effluent limitations, (3) water quality limitations, (4) environmental planning, and (5) best management practices. the desirable control strategy should be based on a system of discharge permits in the case of point source pollution, which includes effluent and water quality limitations. the technology based effluent limitations could be applied as a short-range strategy to control pollution from industrial and domestic point source discharges. the use of water quality standards could become part of a long-range strategy for controlling point sources. for nonpoint sources, it would be virtually impossible to develop effluent limitations. Thus, the implementation of best management practices and effective environmental planning would be the most reasonable control strategy for non-point sources. However, pollution prevention measures could consist of a “black list” of substances that should be completely banned, and a “grey list” for those that should be strictly limited. These lists should be adopted or appropriately modified for the conditions of the Wider Caribbean Region.
The development of control based on the water quality of the receiving body of water involves the collection and analysis of effluent and ambient data to develop water quality based permit limits and to assess compliance with these permits. Finally, any marine pollution control strategy developed by the countries of the Region should be mutually agreed upon and implemented within a period of ten years from the ratification of a protocol on land-based sources of marine pollution. 相似文献
233.
ABSTRACT: The SMEMAX transformation, its modified versions and power transformation were applied to 55 long-term records of annual maximum flood flows tested previously for independence, homogeneity and completeness. Even though SMEMAX transformation reduced the coefficient of skewness to near zero for flood data, their distribution was not a true normal distribution. In almost all cases, the coefficient of kurtosis was quite different from 3.0 of the normal distribution. Empirical criteria showed that SMEMAX transformation performed well only for 40 (70 percent) of the 55 stations tested. Its performance level dropped, especially for stations which had both the coefficient of skewness and kurtosis greater than 3.0 and 10.0, respectively. Power transformation was generally better in transforming the flood data to a normal distribution. It performed well for 50 (90 percent) of the 55 stations tested. The coefficient of skewness in case of the data transformed by power transformation was much closer to the zero value than in the case of SMEMAX transformed series. The SMEMAX transformation and its two modified versions yielded identical results when flood frequency analysis was performed. Computationally, all three methods were equally simple and easy to apply for flood frequency analysis. In some cases, the coefficient of kurtosis for the transformed distributions obtained both by SMEMAX and power transformations deviated farther from that for the normal distribution than for the parent distribution. 相似文献
234.
Sustainable technologies for on-site domestic wastewater treatment: a review with technical approach
Sharma Meena Kumari Tyagi Vinay Kumar Singh Nitin Kumar Singh Surya Pratap Kazmi Absar Ahmad 《Environment, Development and Sustainability》2022,24(3):3039-3090
Environment, Development and Sustainability - The rapid population growth has rendered the centralized sewerage systems a non-realistic option in sparsely populated areas, particularly in... 相似文献
235.
Singh Gaurav Kumar A. R. S. Jaiswal R. K. Singh Surjeet Singh R. M. 《Environment, Development and Sustainability》2022,24(10):12311-12339
Environment, Development and Sustainability - Runoff estimation is of immense importance in hydrological analysis for water resource planning and management. The developing countries cannot afford... 相似文献
236.
Singh A 《Environmental pollution (Barking, Essex : 1987)》1997,95(3):289-291
Net photosynthesis, leaf area, biomass, and number, size and activity of nodules were examined in three leguminous plants subjected under field conditions to supplemental UV-B radiation equivalent to a 15% ozone depletion at 25 degrees N latitude. Enhanced UV-B radiation adversely affected the net photosynthetic rate, growth characteristics and nodule activity in all three species. Maximum reduction in net photosynthesis occurred in Phaseolus mungo cv. Pant U-30, whereas the greatest reduction in nitrogenase activity occurred in Vigna radiata. 相似文献
237.
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239.
Siddiqui ZA Singh LP 《Journal of environmental biology / Academy of Environmental Biology, India》2005,26(1):117-122
Glasshouse experiments were conducted twice to assess the ash amendments (0, 20, and 40% with soil), a phosphate solubilizing microorganism Pseudomonas striata and a root-nodule bacterium Rhizobium sp on the reproduction of root-knot nematode Meloidogyne incognita and on the growth and transpiration of pea. Amendments of fly ash with soil had no effect on transpiration. However, M. incognita reduced the rate of transpiration from 1st week onward after inoculation while inoculation of Rhizobium sp and P. striata increased transpiration from 1st week onward after their inoculation both in nematode inoculated and uninoculated plants. Increase in transpiration was greater when both organisms were inoculated together. Addition of 20 and 40% fly ash with soil was beneficial for plant growth both in nematode inoculated and uninoculated plants. Inoculation of above organisms also increases plant growth of nematode inoculated and uninoculated plants in different fly ash soil mixture but increase in growth was greater when both organisms were inoculated together. Use of 20% fly ash increased galling and nematode multiplication over plants grown in without fly ash while 40% fly ash had adverse effect on galling and nematode multiplication. Rhizobium sp had greater adverse effect on galling and nematode multiplication than P. striata. Use of both organisms together had greater adverse effect on galling and nematode multiplication than caused by either of them alone. Highest reduction in galling and nematode multiplication was observed when both organisms were used in 40% fly ash amended soil. However, highest transpiration was observed in plants without nematodes and inoculated with both organisms together both in with or without fly ash amended soil. 相似文献
240.
Atmospheric depositions around a heavily industrialized area in a seasonally dry tropical environment of India 总被引:1,自引:0,他引:1
Clear and through-fall bulk depositions were collected in the downwind of a highly industrialized region in Sonbhadra district of India to estimate the influence of anthropogenic activities on chemical composition of depositions. Significant spatial and temporal variations in depositions of cations and anions were observed. Depositions were higher near the thermal power stations and coal mines as compared to distantly situated site. Seasonally summer samples showed maximum cation and anion depositions followed by winter and minimum in rainy season. The mean pH of the depositions indicates that rainfall in the area is alkaline. Among the anions, maximum deposition was recorded for SO4(2-) followed by NO3- and minimum for Cl-. Among the cations, Ca2+ deposition was maximum followed by NH4+. Na+, K+ and Mg2+ deposition rates showed more or less similar values. The depositions of cations and anions as well as pH were higher in through-fall than clear-fall samples. Results of the present study suggest that atmospheric depositions are strongly modified due to thermal power stations and coal mines in the area. 相似文献