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highway stormwater runoff quality: development of surrogate parameter relationships
1997
Thomson, N. R. | McBean1, E. A. | Snodgrass, W. | Monstrenko, I. B.
The development of relationships for predicting the impact of highway stormwater runoff is described. The predictive relationships are regression-based equations reflecting variations in the magnitude of the constituents of interest. The objective is to identify a subset of constituents that can be used as surrogates for the remaining constituents as a means of decreasing the costs of collection and measurement of highway stormwater runoff quality data.The Minnesota highway stormwater quality database complied in the late 1970's and early 1980's is employed in identifying the set of surrogate parameters. The findings indicate that total suspended solids, total dissolved solids, total volatile solids, and total organic carbon are effective surrogate parameters for numerous metals, ionic species, and nutrients. The findings also indicated that the developed ionic species constituent relationships are portable, while the metal and nutrient constituent relationships were limited to urban sites with similar environmental conditions. The development of these relationships represents a step towards remediating and preventing the problem of nonpoint source highway pollution.
Show more [+] Less [-]Increased cadmium availability to crops on a sewage-sludge amended soil
1997
Tichý, R. | Ný, V. | Kužel, S. | Kolář, L.
Analysis of spatial distribution of sewage-sludge born cadmium on the experimental plot revealed positive correlation of total cadmium and organic matter. Soil pH fluctuated randomly on the field. ‘Bioavailable’ concentrations, as determined by NH₄-acetate extraction, were closely correlated to the total cadmium levels, and only negligible effects of pH and/or organic matter fluctuations were recorded. Desorption model using modified Freundlich isotherm was applied to predict risks of cadmium solubilization at different conditions. Simulations revealed that the organic matter content within the ranges found at the experimental field cannot support a proper immobilization of cadmium at pH-range observed at the field. The phenomenon was explained by ineffective care for the soil in the past.
Show more [+] Less [-]The difference in brown trout (Salmo Trutta L.) blood composition from acidic and limed sites of two rivers in Western Norway
1997
Galina, Maria S.
Certain blood morphology parameters: red blood cell (RBC) sizes; percentage of polymorphonuclear leukocytes and ratio polychromatocyte/RBC in Brown trout (Salmo trutta L.) from acidified water (mean pH value 4.94) and limed water (mean pH value 5.66) were investigated. The sizes of RBC long axises were significantly larger in fish from acidic environment than from limed condition (14.37 and 12.96μm respectively). The percentage of polymorphonuclear cells (7.86 and 3.32) and polychromatocyte/RBC ratio (0.079 and 0.019) were also significantly larger in fish from the acidified environment. Blood morphology parameters are concluded to be usefull for testing and detection of long-term acidic stress in fish in nature.
Show more [+] Less [-]Effects of metals on the microbial mineralization of organic acids
1997
BRYNHILDSEN, LENA | Rosswall, T. (Thomas)
The effects of chemical speciation on mineralization of organic compounds was studied using citric acid as a model substance. The degradation of ¹⁴C-labeled Al-, Co-, Cu-, and Zn-citrate was followed in chemically well-defined media inoculated with mixed cultures of microorganisms (soil extracts from two soils). The degradation of citrate was completely inhibited when the acid was bound to Zn, Cu, or Co and partly inhibited when bound to Al. The mineralization of citrate as well as histidine was also followed by incubation of the complexes (Cu, Zn, Al) in the two soils. No effect of metals on the degradation of histidine was seen. The degradation of citrate in soils was also unaffected when complexed to Cu and Zn, whereas Al exerted an inhibited decomposition in both soils.
Show more [+] Less [-]Sulphur isotope composition of stream water, moss and humus from eight arctic catchments in the Kola Peninsula region (NW Russia, N Finland, NE Norway)
1997
de Caritat, P. | Krouse, H. R. | Hutcheon, I.
In summer 1994, stream water, moss and humus samples were collected for sulphur isotopic analysis from eight catchments located in the western Kola Peninsula region, where several industrial centres emit high loads of SO₂ and other elements to the atmosphere. Three potential sources of sulphur and their isotopic signatures were identified: (1) marine (δ ³⁴S+20 to +21‰ CDT), (2) anthropogenic emissions (<+10‰), and (3) geogenic (variableδ ³⁴S, mostly <+10‰). Averaged per catchment, the sulphur isotopic composition varies between +6.0 and +16.3‰ for stream water sulphate, +6.0 and +8.4‰ for moss sulphur, and +5.2 and +12.2‰ for humus sulphur. Theδ ³⁴S composition of stream water from the more remote catchments is quite variable, reflecting several natural (geogenic) sources, but it becomes restricted to the range +8 to +10‰ near the pollution sources. A plot ofδ ³⁴S vs. 1:SO₄ in stream water suggests that sulphate originating from the smelters has aδ ³⁴S value ≈+9.5‰, and is a dominant source. Sulphur isotope values for moss and humus are consistent with the deduced composition for the emitted sulphur, though for humus a component of geogenic sulphur incorporated via vegetation uptake may play a role. Further isotopic characterisation of atmospheric emissions, together with environmental samples, is needed to better understand sulphur sources and sinks in the area.
Show more [+] Less [-]Recent lake acidification and recovery trends in southern Quebec, Canada
1997
Bouchard, André
A total of 51 lakes in southern Quebec, Canada, were sampled between 1985 and 1993 to study changes in water chemistry following reductions in SO₂ emissions (main precursor of acid precipitation). Time series analysis of precipitation chemistry revealed significant reductions in concentrations and deposition of SO₄ ²⁻ from 1981 to 1992 in southern Quebec as well as reductions in concentrations and deposition of base cations (Ca²⁺, Mg²⁺), NO₃ ⁻ and H⁺ in the western section of the study area. Reductions in atmospheric inputs inputs of SO₄ ²⁻ have resulted in decreased lakewater SO₄ ²⁻ concentrations in the majority of the lakes in our study, although only a small fraction (9 of 37 lakes used in the temporal analysis) have improved significantly in terms of acidity status (pH, acid neutralizing capacity — ANC). The main response of the lakes to decreased SO₄ ²⁻ is a decrease in base cations (Ca²⁺+Mg²⁺), which was observed in 17 of 37 lakes. Seventeen lakes also showed significant increases in dissolved organic carbon (DOC) over the period of study. The resulting increases in organic acidity as well as the decrease in base cations could both play a role in delaying the recovery of our lakes.
Show more [+] Less [-]Effects of diazinon on some population parameters ofMoina Macrocopa (Cladocera)
1997
Wong, C. K.
The effects of the organophosphate insecticide diazinon on selected population parameters of the freshwater cladoceran Moina macrocopa were studied. Survivorship and average longevity were affected by exposure to 1.00 μg L⁻¹ or higher concentrations. Exposure to diazinon had no effect on the time of first reproduction, but animals did not reproduce in 10.00 μg L⁻¹ and the number of offspring produced by a female during her entire life span was reduced in 1.00 μg L-1. The intrinsic rate of population growth and the generation time were not significantly affected by exposure to diazinon.
Show more [+] Less [-]Sources of trace metals in streams and headwater lakes in finland
1997
TARVAINEN, TIMO | Lahermo, Pertti | MANNIO, JAAKKO
Distributions of Mn, Zn, Cu, Ni, Cr, Pb, As, and Cd in Finnish surface waters were studied by comparing two data sets: samples from 154 headwater lakes collected by the Water and Environment Administration in 1992 and samples from 1165 headwater streams collected during the environmental geochemical mapping program of the Geological Survey of Finland in 1990. It was expected that headwater lakes with catchments smaller than 1 km²; and high lake percentage (ratio of lake area to catchment size) would be more influenced by atmospheric trace metal deposition than the streams, with average catchment size of 30 km²;.The lakes with highest arsenic concentrations lie in an area with greenstones and arsenic-rich black schists. The same lakes have high copper concentrations, which evidently are derived from the Cu-rich greenstones of the catchment. The high copper concentrations of streams and lakes in the industrialized region of the southwest coast are due to several anthropogenic sources.The highest concentrations of chromium occur in brown stream and lake waters rich in humic matter, while manganese and zinc concentrations, which are controlled by acidity, tend to be elevated in low-pH waters. The high nickel concentrations in lakes in southwestern Finland probably are due to anthropogenic input, while Ni anomalies in stream and lake water in eastern Finland are correlated with high Ni contents of glacial till. The lead concentrations in lakes are mainly of airborne anthropogenic origin.The pattern of atmospheric deposition is reflected in the concentrations of Cd, As, Cu, Zn, and Ni in headwater lakes, but land-use, the natural distribution of metals in the overburden, water acidity, and the amount of humic substances influence the distribution of trace metals in both lakes and streams. Thus the trace metal distribution in headwater lakes cannot be used alone to estimate the contribution of anthropogenic atmospheric deposition to metal anomalies in Finnish surface waters.
Show more [+] Less [-]Zero test emissions of sulphur dioxide from large coal under staged fluidized bed combustion
1997
Khan, W. Z. | Gibbs, B. M.
This paper reports the emissions of SO₂ from large coal under staged combustion without any additive. A stainless steel combustor, 2 m high and 0.3×0.3 m in cross section was used. Fluidizing air was supplied through a multihole distributor. An adjustable secondary air injector was used along the vertical axis of the combustor to introduce secondary air in the freeboard. From 0–40% of total air was injected in the freeboard above the bed. The experiments were carried out at fluidizing velocities of 1–2 m s⁻¹, bed temperatures of 1103–1153°K, 20–40% excess air, and bed particle sizes of 665μm. Bed temperature and level of air staging had the most significant effect on SO₂ emissions.
Show more [+] Less [-]Accumulation of cadmium and zinc from diffuse immission on acid sandy soils, as a function of soil composition
1997
Wilkens, B. J. | Loch, J. P. G.
Sandy soils, in the border area of Belgium and the Netherlands (the Kempen region), are heavily contaminated by atmospheric deposition of cadmium and zinc from nearby smelters. Groundwater contamination by leaching from these low retention soils is subject of study. There are reports of high cadmium and zinc concentrations in groundwater in the area, but in most cases the direct sources are unknown. In an attempt to predict present or future risk of groundwater contamination by soil leaching, metal binding processes (retardation) were studied that are specific for these soil types under the existing acidifying conditions. From four fields nine contaminated profiles were sampled and analyzed for cadmium and zinc. Average concentrations of 131μg g⁻¹ zinc and 1.6μg g⁻¹ cadmium with maximum values of 2989μg g⁻¹ respectively 16.3μg g⁻¹ were found. In addition pH and contents of organic matter, aluminium, iron, and manganese were determined. The relative importance of these soil parameters for metal retardation is derived from the profiles. The data show that organic matter is the most important soil component for binding cadmium and zinc. Adsorption of cadmium and zinc on aluminium, iron and manganese (hydr) oxides appears to be of minor importance at low pH (<5.5).
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