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Soil Acidification Induced by Ammonium Sulphate Addition in a Norway Spruce Forest in Southwest Sweden
2003
Bergholm, Johan | Berggren, Dan | Alavi, Ghasem
The contributions of different acidifying processes to the total protonload (TPL) of the soil in control plots (C) and ammonium sulphate treatedplots (NS) were studied in a Norway spruce stand in Southwest Sweden during 1988–1998. The annual deposition of inorganic nitrogen and sulphate was on average 18 kg N and 20 kg S ha⁻¹. In addition the NS treated plots received 100 kg N and 114 kg S ha⁻¹annually. The amounts of nutrients added to the ecosystem by wet and dry deposition and the leaching at 50 cm depth were calculated. The net atmosphericproton load, the proton load by nitrogen transformations in the soil, the sulphate sorption/desorption in the soil and the excess base cation accumulation in biomass were calculated. There was no leaching of inorganic nitrogen from control plots during the study period. The net atmospheric proton deposition, originating from sulphuric and nitric acid deposition, was the main contributor to TPL in control plots. The addition of ammonium sulphate increased the leaching of ammonium, nitrate, sulphate, magnesium and calcium but not of potassium. The TPL in NS plots was about ten times that in control plots. The nitrogen transformation processes were the main contributors to TPL to NS soil, in the beginning by ammonium uptake and later also by nitrification. The pH decreased by 0.4 units in the mineral soil. The between-year variation in TPL during the eleven year period in C plots (200–1500 molcha⁻¹yr⁻¹) and in NS plots (1000–13000 molcha⁻¹yr⁻¹) was mainly dependent on the sorption or release of sulphate. Both in C and NS, the TPL was buffered mainly by dissolving solid aluminium compounds, most probably some Al(OH)₃phase.
显示更多 [+] 显示较少 [-]Comparison of Heavy Metal Adsorptions by Thai Kaolin and Ballclay
2003
Chantawong, V. | Harvey, N. W. | Bashkin, V. N.
The adsorption characteristics of heavy metals: cadmium(II), chromium(III), copper(II), nickel(II), lead(II), and zinc(II) ions by kaolin (kaolinite) and ballclay (illite) from Thailand were studied. This research was focussed on the pH, adsorption isotherms of single-metal solutions at 30–60 °C by batch experiments, and on ion selectivityin mixed and binary combination solutions. It was found that, except Ni, metal adsorption increased with increased pH of the solutions and their adsorption followed both Langmuir and Freundlich isotherms. Adsorption of metals in the mixture solutions by kaolin was: Cr > Zn > Cu ≈ Cd ≈ Ni > Pb, and for ballclay was: Cr > Zn > Cu > Cd ≈ Pb > Ni. The adsorption of metals was endothermic, with the exception of Cd, Pb and Zn for kaolin, Cu and Zn for ballclay. Kaolin and ballclay exhibited relatively hard Lewis base adsorption site. The presence of other metals may reduce or promote the adsorption of heavy metals. The presence of Cr³⁺induced the greatest reduction of metal adsorptiononto kaolin, as did the presence of Cu²⁺for ballclay.
显示更多 [+] 显示较少 [-]Chemical degradation methods for wastes and pollutants
2003
Tarr, Matthew A.
Assessment of industrial pollution
2003
In the Indian context.
显示更多 [+] 显示较少 [-]Agriculture non-point source pollution control | Agriculture nonpoint source pollution control
2003
Cestti, Rita | Srivastava, Jitendra | Jung, Samira
Annotation This publication aims to draw the attention of professionals and practitioners working in agricultural and environmental sectors to the experience and successes of the environmentally friendly good agricultural practices being used in the Chesapeake Bay Region of the United States to reduce nutrient loads in water. | Annotation Over the last few decades the quality of many international water bodies has deteriorated, resulting in economic losses from declines in the fishing industry and in tourism, as well as a loss of biodiversity and health impacts from contaminated water. This deterioration has been caused by many factors including nutrient run-off from agriculture, insufficiently treated sewage, drainage of wetlands, coastal erosion, introduction of exotic species, eutrophication and inadequate resource management. One of the most significant sources of degradation has been form excessive discharge of nitrogen and phosphorus compounds (nutrients), due to the poor management practices used in agricultural, domestic and industrial activities. This publication aims to draw the attention of professionals and practitioners working in agricultural and environmental sectors to the experience and successes of the environmentally friendly good agricultural practices being used in the Chesapeake Bay Region of the United States to reduce nutrient loads in water.
显示更多 [+] 显示较少 [-]Drinking water quality in Podgorica [Montenegro, Serbia&Montenegro] - dependence of chlorination by products concentration on the organic matter in water
2003
Karajic, M. | Djurovic, D. (Institut za zdravlje Crne Gore, Podgorica (Serbia and Montenegro))
Presentation is dealing with data on raw and drinking water quality of water supply sources and water supply systems in Podgorica, Montenegro (Serbia&Montenegro). Special attention was paid to organic matter content, concentration of disinfectants and disinfection by-products. Average values of all parameters examined are below maximum permissible levels defined by regulations. That means that physical-chemical quality of water is excellent.
显示更多 [+] 显示较少 [-]Lake Ohrid littoral water characteristics according to comparative parameters
2003
Novevska, V. | Vasileska, A. (Hidrobioloski zavod, Ohrid (The Former Yugoslav Republic of Macedonia))
Water quality analyses were performed on littoral water samples, collected on Lake Ohrid in 2002 (January, February, June, July, August and September). Several microbiological parameters were compared. The number of Escherichia coli, the number of organotrophic bacteria and the phosphatase activity index were measured. Samples were collected along the shore of Lake Ohrid, i.e. at the village of Pestani, at Hotel Metropol, in Ohrid Bay and at the lake inflow of River Velgoska. The results of the study show that the different parameters are not compatible in terms of water quality characterization. The differences found are discussed below.
显示更多 [+] 显示较少 [-]Penilia avirostris - indicator of refreshed and eutrophic water
2003
Vukanic, V. (Institut za biologiju mora, Kotor (Serbia and Montenegro))
During the analyses of zooplankton and hydrography samples from continuous field research in monthly series during 2002 on three shallow stations (Orahovac, Morinj and near the Institute) and 4 central stations in Boka Kotorska Bay (Adriatic sea, Montenegro (Serbia&Montenegro)), exceptionally dense populations of Penilia avirostris were observed. Presence of this species in refreshed waters during the summer in other parts of Adriatic and Mediterranean, and its designation as an indicator, are reasons for presentation of these gathered results from yearly cycle in Boka Kotorska Bay.
显示更多 [+] 显示较少 [-]Physical and chemical properties as well as the contents of dominating ions in spring waters of Zlatibor region [Serbia, Serbia&Montenegro] whose capacities and locations may satisfy the requirements for their bottling
2003
Stevanetic, V. (Zavod za zastitu zdravlja, Uzice (Serbia and Montenegro))
Nowadays people increasingly use bottled water for drinking which makes bottling a very profitable business. The aim of this paper is better understanding of physical and chemical properties as well as the contents of dominating ions and microbiological purity of 13 spring waters existing on the territory of Zlatibor region (Serbia, Serbia&Montenegro) which according to its water capacity, its watershed features and good roads availability may be further explored for the purpose of water bottling.
显示更多 [+] 显示较少 [-]Eutrophication and bacterial pollution of the Montenegrian coastal sea during 2002
2003
Regner, D. | Vuksanovic, N. | Stjepcevic, B. | Joksimovic, D. (Institut za biologiju mora, Kotor (Serbia and Montenegro))
In this paper, results of seasonal investigations throughout 2002, important for evaluation of the eutrophication and bacterial pollution of the Montenegrin coastal sea were presented. It was established that the difference between warmer and colder periods of the year was highest in the part of the Montenegrin coastal sea exposed to the strongest impact of the open waters of the Southern Adriatic.
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