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Effects of nitrogen deposition on tree growth and soil nutrients in boreal scots pine stands
1998
Nissinen, A. | Hari, P. (Department of Forest Ecology, P.O. Box 24, University of Helsinki, 00014 Helsinki (Finland))
Evaluation of heavy metal lability in polluted soils by a cation exchange batch procedure
1998
Esnaola, M.V. | Millan, E. (Departamento de Quimica Aplicada Facultad de Quimica, Universidad del Pais Vasco, Apdo. 1072, 20080 San Sebastian (Spain))
Removal of trace metals from contaminated soils using EDTA incorporating resin trapping techniques
1998
Tejowulan, R.S. | Hendershot, W.H. (Department of Soil Science, University of Mantaram, Jin. Pendidikan No. 56, Mantaram, NTB (Indonesia))
Effects of enhanced N deposition as (NH4)2SO4 and HNO3 on base cation leaching from podzol microcosms
1998
White, C.C. | Cresser, M.S. (Department of Plant and Soil Science, University of Aberdeen, Cruickshank Building, Aberdeen, AB24 3UU (United Kingdom))
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.
Show more [+] Less [-]Effect of organic materials on partitioning, extractability and plant uptake of metals in an alum shale soil
1998
Narwal, R.P. (Agricultural Univ. of Norway, Aas (Norway). Dept. of Soil and Water Sciences) | Singh, B.R.
Modelling acidification effects on coniferous forest soils
1998
Eriksson, E. (Uppsala Univ. (Sweden). Dept. of Geosciences)
