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Regulating pollution
1997
Davies, J. Clarence | Mazurek, Jan
What laws, processes, and institutions exist to protect the American environment? To what degree do they succeed, and where do they fall short? This important new book concisely describes and evaluates America's pollution control system. It concludes, "For all its accomplishments... the pollution control regulatory system is deeply and fundamentally flawed." The authors, analysts with RFF's Center for Risk Management, examine the fragmented tangle of statutes, regulatory bodies, and programs designed to control environmental degradation in the United States. CRM Director Davies and Mazurek employ carefully chosen criteria such as pollution reduction, economic efficiency, and responsiveness to social values in order to judge the effectiveness of the various instruments -- and the system as a whole -- in protecting the environment. Their description of the system is concise and clear, and their selection of criteria is an important contribution to program evaluation. The book also compares U.S. performance with that of other countries. The authors' goal is a critical understanding of pollution regulation in the United States, thus laying the groundwork for improving it. Regulating Pollution emerges from a major research project undertaken by RFF's Center for Risk Management with support from the Andrew W. Mellon and Smith Richardson foundations. The three-year project constitutes the first in-depth, systematic evaluation of U.S. pollution control efforts.
Показать больше [+] Меньше [-]Air pollution
1997
Michaelis, W. (Walfried)
Controlling pollution
1997
Mehta, Shekhar | Mundle, Sudipto | Sankar, U.
The state of India's environment has been deteriorating steadily over the past two decades. Ambient standards of air, water and soil pollution are routinely exceeded with potentially disastrous consequences. Recognising the seriousness of the problem, the Indian government has recently introduced a series of measures which concentrate on practical aspects of implementation. | However, there are few studies available which can guide the formulation of policies in terms of the most appropriate choice of instruments which can contain pollution and protect India's environment. | That is the central purpose of this pioneering study - namely, to assess the efficacy of alternative instruments for pollution abatement based both on theoretical explorations and real-life case studies. The authors begin by reviewing the existing policy regime and analysing its impact on the quality of air and water in India's cities and rivers respectively. They then proceed to assess the choice of instruments for pollution control by linking economic and environmental systems.
Показать больше [+] Меньше [-]The body's battle against pollution
1997
Olinescu, Radu | Smith, Terrance L. | Hertoghe, J.
Relationship between sugar maple decline and corresponding chemical changes in the stem tissue
1997
Mohamed, H. K. | Pathak, S. | Roy, D. N. | Hutchinson, T. C. | McLaughlin, D. L. | Kinch, J. C.
Wood cores were taken at breast height of mature sugar maple (Acer Saccharum Marsh.) trees of approximately the same age from four sites in Ontario, Canada differing in soil characteristics and general tree health. The soils of two of the sites were acidic (podzols), while the soils of the other two sites were calcareous (brunisols). Selected elemental analyses using Neutron Activation Analysis were conducted on the soils and the xylem wood of the sugar maple trees, and the results were compared relative to tree health. Aluminum in stem xylem was found to be significantly higher in declining trees (mean 7.7 ppm) relative to the healthy trees (mean 4.0) from the acidic sites, where aluminum was freely available in the soil. Soil extractable aluminum was also significantly higher in the soil adjacent to the declining trees (mean 5.10) compared to the healthy trees (mean 3.20). These results show that xylem aluminum contents reflect the increased availability of aluminum in acidifying soils and provide additional evidence that dendrochemistry may be used as a proxy environmental monitoring tool.
Показать больше [+] Меньше [-]Impact of high aluminium loading on a small catchment area (thuringia slate mining area) —geochemical transformations and hydrological transport
1997
Peiffer, Stefan | Beierkuhnlein, Carl | Sandhage-Hofmann, Alexandra | Kaupenjohann, Martin | Bär, Silke
A field study was performed on the effects of acid mine leachate from slate mine tailings seeping into a small river passing through the tailings. Before entering the tailings the river water has high alkalinity which neutralizes acidity upon mixing with leachate within the tailings. Donwstreams of the tailings the pH of the river water ranges about pH = 8, the water contains high concentrations of sulfate (≈1500 μmol/1 and particulate bound aluminium (≈80 μmol/I), but low concentrations of dissolved aluminium (≈3 μmol/1). It is therefore assumed that AI(OH)₃ colloids are precipitated during the neutralisation process and transported out of the tailings. The concentration of particulate bound aluminium along the river shows a strong correlation with the concentration of sulfate, which indicates that particulate bound aluminium is conservative. It therefore seems that under dry weather conditions (under most of the sampling was performed) no chemical retention mechanism exists which confines the distribution of aluminium to a restricted part of the catchment area. In contrast, the white river sediment is rich in both aluminium and sulfate, which suggests the temporary formation of aluminium hydroxosulfate minerals. Favorable (i.e. acidic) conditions may prevail at high discharges where the acidity accumulated in the tailings is flushed into the river with its subsequent acidification.
Показать больше [+] Меньше [-]Oil and gas industrial chemicals' cytotoxicity studied by allium test
1997
Zoldoš, Vlatka | Vidaković-Cifrek, Željka | Tomić, Mihovil | Papeš, Dražena
Allium test has already been used to determine cytotoxicity of waste drilling fluids. In the present work the cytotoxicity of four pure chemicals (Defoamex, Idthin 400, Magco Thin and Slick Pipe) was investigated. Those chemicals are components of drilling fluids, therefore, they are usually constituents of oil and gas industry waste waters. The tested chemicals were prepared in 1:9 dilution and cytotoxic effects on root-tip meristem ofAllium ascalonicum were analysed after 24-, 48- and 72-hour-treatments. All samples showed cytotoxicity which was proved by cytogenetic parameters such as inhibition of mitotic activity and increase of mitotic abnormalities and chromosomal aberrations in comparison with the control. Almost all mitotic abnormalities induced by four chemicals tested were the result of disturbed spindle mechanisms accompanied with stickiness. Slick Pipe revealed the most prominent mitodepressive effect and induced a high number of abnormalities. It caused a significant decrease of mitotic activity and increase of mitotic abnormalities after all three treatment durations, while chemicals Defoamex and Magco Thin showed a significant decrease of mitotic activity only after 72-hour-treatment. Chemicals Defoamex, Idthin 400 and Magco Thin revealed a significant increase of mitotic abnormalities after 48- and 72-hour-treatments.
Показать больше [+] Меньше [-]Metal extractability and availability in a soil after heavy application of either nickel or lead in different forms
1997
NOGALES, R. | GALLARDO-LARA, F. | BENITEZ, E. | Soto, J. | HERVAS, D. | Polo, A.
A greenhouse experiment using soil was conducted to investigate the effects of the addition of different forms of either nickel or lead, together with an acidifying agent, on the distribution of Ni, Pb, Zn, Cu and Mn in wheat plants, and on the post-harvest extractability of these elements in the soil. Two treatments consisting of soil alone or soil mixed with sewage sludge at a rate of 200 Mg ha⁻¹ were used as controls. Nickel (400 mg kg⁻¹) or lead (1600 mg kg⁻¹) was added to the soil as an inorganic salt or mixed previously with sewage sludge. Six further treatments including an acidifying agent (wastewater from olive oil processing: alpechin) were also prepared. Wheat (Triticum aestivum L. var. Mesa) plants were harvested 75 d after germination. Dry matter yield of wheat was increased by the addition of sewage sludge. No reductions in yield were observed after the addition of nickel or lead. Nickel concentration and uptake by wheat, and extractability from soil, were higher when the sewage sludge enriched in nickel was added to soil. This effect was enhanced when the acidifying agent was also added. In contrast, lead availability was higher after the addition of inorganic Pb to soil. The addition of both forms of Ni enhanced Zn, Cu and Mn uptake by the plant, whereas the addition of lead increased Zn and Cu. After harvesting, increases in extractable Zn and Cu in the soil were observed only in treatments with sewage sludge, and not after the addition of Ni or Pb, or after the addition of the acidifying agent. Decreasing the pH of the soil with the acidifying agent tended to increase Mn uptake by wheat, and Mn extractability from the soil after harvesting.
Показать больше [+] Меньше [-]Major pathways for nitrogen removal in waste water stabilization ponds
1997
Lai, Patrick C. C. | Lam, Paul K. S.
A study on the factors influencing nitrogen removal in waste water stabilization ponds was undertaken in an eight-pond series in Werribee, Australia. Nitrogen species including Kjeldahl nitrogen, total ammonia nitrogen, nitrite and nitrate were monitored monthly from March 1993 to January 1994. At the same time, pH, temperature, chlorophylla content and dissolved oxygen were also recorded. Highest nitrogen removal occurred during the period with highest levels of chlorophylla content and dissolved oxygen, but the rate of nitrogen removal was not related to temperature and pH. Enhanced photosynthetic activities resulting from an increased phytoplankton abundance due to prolonged detention time caused an increase in dissolved oxygen, and created an optimum condition for nitrification to occur. In this process, ammonia was oxidized to nitrite and nitrate which were subsequently reduced to elemental nitrogen. Apart from nitrification-denitrification which was the major nitrogen removal pathway in the study system, algal uptake of ammonium, nitrate and nitrite as nutrient sources also contributed to the nitrogen removal. The role of phytoplankton and zooplankton in the treatment process in waste stabilization ponds was discussed.
Показать больше [+] Меньше [-]a new high-pressure squeezing technique for pore fluid extraction from terrestrial soils
1997
Böttcher, Gerd | Brumsack, Hans-J. | Heinrichs, H. (Hartmut) | Pohlmann, Markus
A new plastic-lined high-pressure squeezing device has been developed for the extraction of soil pore solutions. At a maximum pressure of 1100 kg cm⁻² the water recovery ranged between 30 and 55% of the total water content. Pressure dependent squeezing experiments showed a general increase in Si, Mn, Mg, Ca, K, Na, Al, Fe, Cd, and Zn concentrations with progressive pore water extraction and increasing pressure, indicating that micro pore solutes have the highest concentrations of solutes. Soil samples with moisture contents of more than about 15% generally provided enough water for major and trace element analyses. The data do not reveal any contamination of the pore fluids from the squeezing device. An advantage of this method is that the solution could be closely related to a specific soil horizon on a cm scale and also to the time of sampling. A further application of this squeezing method is the possibility of pressure dependent sequential squeezing to obtain fluids from different pore spaces.
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