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Global air emission inventories for anthropogenic sources of NOX, NH3 and N2O in 1990
1998
Olivier, J.G.J. | Bouwman, A.F. | Hoek, K.W. van der | Berdowski, J.J.M. (National Institute of Public Health and the Environment (RIVM), P.O. Box 1, NL-3720 BA Bilthoven (Netherlands))
Soil nitrous oxide and nitric oxide emissions as indicators of elevated atmospheric N deposition rates in seminatural ecosystems
1998
Skiba, U. | Sheppard, L. | Pitcairn, C.E.R. | Leith, I. | Crossley, A. | Dijk, S. van | Kennedy, V.H. | Fowler, D. (Institute of Terrestrial Ecology (ITE), Bush Estate, Penicuik EH26 0QB (United Kingdom))
Developmental instability in grayling (Thymallus thymallus) exposed to methylmercury during embryogenesis
1998
Voellestad, L.A. | Fjeld, E. | Haugen, T. | Oxnevad, S.A. (Division of Zoology, Department of Biology, University of Oslo, PO Box 1050, Blindern, N-0316 Oslo (Norway))
Critical loads for nitrogen deposition and their exceedance at European scale
1998
Kuylenstierna, J.C.I. | Hicks, W.K. | Cinderby, S. | Cambridge, H. (Stockholm Environment Institute at York, University of York, P.O. Box 373, York YO10 5YW (United Kingdom))
Effects of low pH and aluminum on root morphology of Japanese red cedar saplings
1998
Hirano, Y. | Hijii, N. (Laboratory of Forest Protection, School of Agricultural Sciences, Nagoya University, Nagoya 464-8601 (Japan))
Integrated pollution control | Umweltschutztechnik. English
1998
Förstner, Ulrich
Sustainable development and pollution control are the key factors in the development of strategies for the solution of environmental problems. This book offers an integrated treatment of all aspects of environmental protection and remediation. The presentation encompasses physical and chemical fundamentals, technological approaches as well as ecological, economic, and ethical aspects. The discussion of regulatory issues includes a comparison of environmental legislation in the US, Japan, and Europe. The book addresses students as a comprehensive text and serves as a handy reference for environmental professionals in industry, consulting services, administration, and environmental agencies and associations.
Mostrar más [+] Menos [-]Effects of Alkalinity and External Sulphate and Phosphorus Load on Water Chemistry in Enclosures in an Eutrophic Shallow Lake
1998
Bellemakers, Martijn J. S. | Maessen, Mario
As a result of changes in hydrology, the former mesotrophic, shallow lake Naardermeer, has been eutrophicated during the last decades. To compensate for shortage of water, eutrophicated water with different chemical characteristics has been supplied. In order to determine the effects of alkalinity, acidity and external sulphate and phosphorus load on eutrophication processes, developments in water chemistry have been studied in enclosures. A decrease of the phosphorus load of the lake did not improve water quality on the short term. This observation was confirmed by this enclosure experiment. Reduction of alkalinity did improve water quality, particularly by reductions of turbidity and chlorophyll-a content. The significant increase in sulphate load in the water layer led to deterioriation of the water quality and an increased biomass of sessile algae by internal eutrophication, probably as a result of increased sulphate reduction in the sediment. Therefore, it seems that lowering of sulphate concentrations in the inlet water after the removal of phosphorus is necessary to improve the water chemistry. The best option, however, is to restore the former hydrological conditions after which the system will be fed only by seepage of groundwater poor in nutrients and sulphate.
Mostrar más [+] Menos [-]Studies of Soils, Soil Water and Stream Water at a Small Catchment near Guiyang, China
1998
Larssen, Thorjørn | Jiling, Xiong | Vogt, Rolf D. | Seip, Hans Martin | Bohan, Liao | Dianwu, Zhao
Acid deposition is considered to be a major environmental problem in China, but information about effects on soils and waters is scarce. To contribute to increased knowledge about the problem a small catchment (about 7 ha) in the outskirts of Guiyang, the provincial capital of Guizhou in south-western China, was instrumented for collection of precipitation, throughfall, soil water and stream water. In addition soil samples have been collected and analyzed for key properties. Median pH in the precipitation is 4.40 (quartiles: 4.19 and 4.77) and the median sulfate concentration 228 µeq/L (quartiles: 147 and 334 µeq/L). The dry deposition of both SO₂ and alkaline dust is considerable. The sum of wet deposition of sulfate and dry deposition of SO₂ has been estimated to about 8.5 gSm⁻²yr⁻¹. The total S-deposition may be somewhat higher due to dry deposition of sulfate and occult deposition. In soil water, SO₄ ²⁻ is the major anion, generally ranging from 300 to 2500 µeq/L in the different plots. Calcium is an important cation, but there is also a considerable contribution of aluminum from the soil. In some of the plots the concentrations of inorganic monomeric aluminum (Ali) are typically between 200 and 400 µm. Potential harmful levels of aluminum and/or high Ali/(Ca²⁺ + Mg²⁺) molar ratios occur in the catchment, but damages to vegetation have not yet been reported. In most cases exchangeable aluminum accounts for between 75 and 95% of the total effective cation exchange capacity (CECE) in the mineral soils. The aluminum chemistry cannot easily be explained by conventional models as the Gaines-Thomas ion-exchange equation or equilibrium with an Al(OH)₃ mineral phase. The stream water is generally less acidic and has considerably lower concentrations of aluminum than the soil water, even though quite acid events have been observed (pH < 4.4). The median pH values are 4.9 and 5.0 in the two first order streams and 6.3 in the dam at the lower boarder of the catchment.
Mostrar más [+] Menos [-]Water supply and pollution control
1998
Viessman, Warren | Hammer, Mark J.
Resource added for the Environmental Engineering Waste and Water Technology program 105062.
Mostrar más [+] Menos [-]Occurrence of persistent organic contaminants and related substances in Hong Kong marine areas: an overview
1998
Connell, D.W. | Wu, R.S.S. | Richardson, B.J. | Leung, K. | Lam, P.S.K. | Connell, P.A. (Centre for Environmental Science and Technology, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China))