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Polish mountain forests: past, present and future
1997
Grodzinska, K. | Szarek-Lukaszewska, G. (W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Krakow (Poland))
Ambient tropospheric ozone in the Ukrainian Carpathian Mountains and Kiev region: detection with passive samplers and bioindicators plants
1997
Blum, O. | Bytnerowicz, A. | Manning, W. | Popovicheva, L. (Central Botanical Garden, National Academy of Sciences, Timiryazevskaya St 1, 252014 Kiev (Ukraine))
Evaluation of ozone injury on foliage of black berry (Prunus serotina) and tall milkweed (Asclepias exaltata) in Great Smoky Mountains National Park
1997
Chappelka, A. | Renfro, J. | Somers, G. | Nash, B. (School of Forestry, Auburn University, Auburn, AL 36849 (USA))
Deterioration of forests in the Sudety Mountains, Poland, detected on satellite images
1997
Bochenek, Z. | Ciolkosz, A. | Iracka, M. (Institute of Geodesy and Cartography, Remote Sensing and Spatial Information Centre-OPLIS, ul.Jasna 2/4, 00-950 Warsaw (Poland))
Air pollution status of a representative site in the Czech Republic Brdy Mountains
1997
Zeller, K. | Cerny, M. | Bytnerowicz, A. | Smith, L. | Sestak, M. | Michalec, M. | Pernegr, V. | Kucera, J (USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Ft. Collins, CO (USA))
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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