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Effect of pluviographic parameters and runoff on suspended sediment concentration in small streams
1998
Stefanovic, J. | Bulajic, Z. (Institut za zemljiste, Beograd (Yugoslavia))
Hydrological, psamological and pluviographical measurements in experimental watershed area in the watershed of River Topciderska (Serbia, Yugoslavia) was analyzed. Interrelations between suspended sediment concentration in streams on the one hand and runoff, rainfall, rainfall intensity and index of previous rainfall on the other hand was came from this analyze. Effects of these parameters on suspended sediment concentration was considered for a single rainfall epizode, during the period of torrential waves and as annual value. Specific coefficients (coefficient of annual rainfall structure and coefficient of annual runoff structure) were used in this paper, with help of them effects of torrential waves and intensity rainfall on average annual suspended sediment concentration were considered.
显示更多 [+] 显示较少 [-][Protective utilization of water and land in the Bistrica river basin [Montenegro, Yugoslavia]]
1998
Popovic, V. (Institut za zemljiste, Beograd (Yugoslavia)) | Ivanovic, S. | Ivanovic, S. | Petrovic, P.
In this paper, we are consider processing of soils erosion and his way on protection expoitation of water for population water supply, melioration's systems for irrigation and for strew of manger of the Lim river with the tug and suspend bank (Montenegro, Yugoslavia). We are given suggestions for protective utilization of agricultural and forest lands and the possibilities of water exploitation from Bistrica river (Montenegro, Yugoslavia). That is useful for fishing, irrigation, energetic, tourism and water supply. In this paper, you can meet some suggestions about exploitations of minerals and organic fertilizars that are not toxics and they not any influence on pollution of land and water.
显示更多 [+] 显示较少 [-]The dynamics of dissolved nitrogen in a blanket peat dominated catchment
1998
Adamson, J.K. | Scott, W.A. | Rowland, A.P. (Environmental Change Network, Institute of Terrestrial Ecology, Merlewood Research Station, Grange-over-Sands, Cumbria, LA11 6JU (United Kingdom))
The impact of land use on N2O emissions from watersheds draining into the Northeastern Atlantic Ocean and European Seas
1998
Kroeze, C. | Seitzinger, S.P. (WIMEK, Wageningen Agricultural University, Wageningen (Netherlands))
Polychlorinated biphenyls in a rural watershed in the southern prairie region of Canada
1998
Rawn, D.F.K. | Halldorson, T.H.J. | Lawson, B.D. | Muir, D.C.G. (Department of Soil Science, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 (Canada))
Nitrogen deposition in Canada's Boreal Shield: implications for the Kyoto Protocol
1998
Brydges, T.G. (39 Elizabeth Street South, Brampton, Ontario, Canada L6Y 1RR2 (Canada))
Application of a conceptual catchment scale nitrate transport model on two rural river basins
1998
Herpe, Y. van | Troch, P.A. | Callewier, L. | Quinn, P.F. (Laboratory of Hydrology and Water Management, University of Gent, Gent (Belgium))
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.
显示更多 [+] 显示较少 [-]Airborne Pollution in Five Drainage Basins in Eastern Finnmark, Norway: an Evaluation of Overbank Sediments as Sampling Medium for Environmental Studies and Geochemical Mapping
1998
Langedal, Marianne | Ottesen, Rolf Tore
To study whether airborne pollution can be detected in overbank sediments, samples collected from five overbank sediment profiles in eastern Finnmark, Norway, at 1 cm depth intervals, were subjected to chemical analysis and ²¹⁰Pb dating. The studied drainage basins constitute parts of an area polluted by emissions from two Ni-Cu smelters in Russia. In the most polluted catchment area, the surface sample showed a 5-fold higher Ni concentration and a 3-fold higher Cu concentration than the pre-industrial sediments at depth. The increases started at the same time as the smelters. Slight Ni increases were also detected in the neighbouring drainage basin, while no significant concentration change was seen in drainage basins previously shown to be only weakly influenced by the smelter emissions. In the most polluted drainage basin, the increase in Ni accumulation rate did not equal the airborne deposition rate. Selective surface erosion of fine grained particles with adhering airborne Ni has probably caused excess Ni accumulation in both overbank and lake sediments. On the contrary, opening of minerogenic point sources may dilute the pollutant concentrations in the drainage sediments. Thus, dating of the sediment profiles is necessary to determine the airborne pollutant accumulation rates. However, dating is not necessary to map the resultant concentration increase, that may show the increased exposure of humans and biota in contact with the sediments.
显示更多 [+] 显示较少 [-]Athmospheric deposition and soil solution chemistry on plots of third monitoring level in the Sance watershed, Beskids Mts. [Czech Republic]
1998
Moravcik, P. (Ustav pro Vyzkum Lesnich Ekosystemu, Jilove u Prahy (Czech Republic))