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النتائج 1 - 10 من 11
Cadmium availability to wheat in five soil series from the Yonne district, Burgundy, France.
1997
Mench M. | Baize D. | Mocquot B.
Anthropogenic impacts on natural nitrogen isotope variations in Pinus sylvestris stands in an industrially polluted area
1997
Jung, K. | Gebauer, G. | Gehre, M. | Hofmann, D. | Weissflog, L. | Schuurmann, G. (Department of Chemical Ecotoxicology, Centre for Environmental Research Leipzig-Halle, P.O. Box 2, D-04301 Leipzig (Germany))
The influence of air pollutants on needles and stems of Scots pine (Pinus sylvestris L.) trees
1997
Kurczynska, E.U. | Dmuchowski, W. | Wloch, W. | Bytnerowicz, A. (Department of Biophysics and Cell Biology, Silesian University, ul. Jagiellonska 28, 40-034 Katowice (Poland))
The synergism between SO2 oxidation and manganese leaching on spruce needles - a chamber experiment
1997
Burkhardt, J. | Drechsel, P. (Department of Agroecology, University of Bayreuth, D-95440 Bayreuth (Germany))
Stemflow chemistry of urban street trees
1997
Takagi, M. | Sasaki, S. | Gyokusen, K. | Saito, A. (Department of Silviculture, Faculty of Agriculture, Kyushu University, Fukuoka 812 (Japan))
Interactions between the Encelia leaf beetle and its host plant, Encelia farinosa: the influence of acidic fog on insect growth and plant chemistry
1997
Redak, R.A. | Trumble, J.T. | Paine, T.D. (Department of Entomology, University of California, Riverside, CA 92521 (USA))
The uptake of particulates by an urban woodland: site description and particulate composition
1997
Freer-Smith, P.H. | Holloway, S. | Goodman, A. (Forestry Commission Research Division, Alice Holt Lodge, Wrecclesham, Farnham, Surrey, GU10 4LH, UK)
Thallium in French agrosystems-II. Concentration of thallium in field-grown rape and some other plant species
1997
Tremel, A. | Masson, P. | Garraud, H. | Donard, O.F.X. | Baize, D. | Mench, M. (Unite d'Agronomie, INRA, Centre Bordeaux-Aquitaine, BP 81, F-33883 Villenave d'Ornon (France))
Long term evolution of petroleum biomarkers in Mangrove soil (Guadeloupe)
1997
Munoz, D. | Guiliano, M. | Doumenq, P. | Jacquot, F. | Scherrer, P. | Mille, G. (Laboratoire de Chimie Analytique de l'Environnement, Case 312, Faculte des Sciences et Techniques de St Jerome, 13397 Marseille Cedex 20 (France))
Whole-catchment liming at Tjønnstrond, Norway: An 11-year record
1997
Traaen, T. S. | Frogner, T. | Hindar, A. | Kleiven, E. | Lande, A. | Wright, R. F.
In June 1983 a whole-catchment liming experiment was conducted at Tjønnstrond, southernmost Norway, to test the utility of terrestrial liming as a technique to restore fish populations in remote lakes with short water-retention times. Tjønnstrond consists of 2 small ponds of 3.0 and 1.5 ha in area which drain a 25-ha catchment. The area is located at about 650–700 meters above sea-level in sparse and unproductive forests of spruce, pine and birch with abundant peatlands. A dose of 3 ton/ha of powdered limestone were spread by helicopter to the terrestrial area. No limestone was added to the ponds themselves. The ponds were subsequently stocked with brown and brook trout.Liming caused large and immediate changes in surface water chemistry; pH increased from 4.5 to 7.0, Ca increased from 40 to 200μeq/L, ANC increased from −30 to +70μeq/L, and reactive-Al decreased from about 10 to 3μmol/L. During the subsequent 11 years the chemical composition of runoff has decreased gradually back towards the acidic pre-treatment situation. The major trends in concentrations of runoff Ca, ANC, pH, Al and NO₃ in runoff are all well simulated by the acidification model MAGIC. Neither the measured data nor the MAGIC simulations indicate significant changes in any other major ion as a result of liming.The soils at Tjønnstrond in 1992 contained significantly higher amounts of exchangeable Ca relative to those at the untreated reference catchment Storgama. In 1992 about 75% of the added Ca remains in the soil as exchangeable Ca, 15% has been lost in runoff, and 10% is unaccounted for.The whole-catchment liming experiment at Tjønnstrond clearly demonstrates that this liming technique produces a long-term stable and favourable water quality for fish. Brown trout in both ponds in 1994 have good condition factors, which indicate that the fish are not stressed by marginal water quality due to re-acidification. The water quality is still adequate after 11 years and >20 water renewals. Concentrations of H⁺ and inorganic Al have gradually increased and approach levels toxic to trout, but the toxicity of these are offset by the continued elevated Ca concentrations. Reduced sulphate deposition during the last 4 years (1990–94) has also helped to slow and even reverse the rate of reacidification. The experiment at Tjønnstrond demonstrates that for this type of upland, remote terrain typical of large areas of southern Norway, terrestrial liming offers a suitable mitigation technique for treating acidified surface waters with short retention times.
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