Metal deposition patterns in central Scotland,as determined by Lichen transplants

Lichen transplants of Hypogymnia physodes were used in a high-density network of sites for collecting airborne metals from the atmosphere in Armadale, a small industrial town in central Scotland. The mapping of the concentrations of various metals revealed a gradient of metal values which decreased outwards from the town's steel foundry. The findings were discussed in the context of a previous epidemiological investigation of lung disease in the town.     

Distributions of lead and cadmium in dust in the vicinity of a sewage sludge incinerator

The content of lead and cadmium in surface dust within a 4 km radius of a sewage sludge incinerator has been investigated. Particular attention was given to Pb and Cd in different size fractions of dust, an aspect not explored in previous studies, and the differences between expressions of contamination as concentration or loading were examined. Despite suggestions from reports that sludge incinerators may have difficulty in complying with emission standards, the present investigation found little evidence for a major contribution to local pollution by the incinerator. Certainly, the highest Cd level was found some 2.2 km downwind of the prevailing wind direction from the incinerator, suggesting some resultant contamination, although the levels do not appear to be excessive. Similar observations apply to Pb contamination of the area. While data of the type produced in this study contribute to an understanding of environmental quality, both loadings and levels need to be considered, as the implications of only consideration one of these may be limited and even misleading.     

Seasonal Variation of Chemical Composition in Fine Particles at Gosan, Korea

PM_2.5 aerosol samples were collected at Gosan in Jeju Island during six intensive measurement periods between November 2001 and August 2003. In order to investigate the chemical composition of fine particles, major ion components, trace elements, and elemental and organic carbon were analyzed. Quite different seasonal characteristic in the chemical composition of fine particles was observed. The concentration of most secondary aerosol components showed a summer minimum and a winter maximum with higher correlation between them at Gosan. This fact clearly reveals the possibility of long-range transport of such pollutants in winter. On the other hand, OC and EC had the highest concentration and good correlation with ion components, such as K⁺, Ca²⁺ in fall. It means that biomass burning could significantly influence the ambient fine carbonaceous particulate in fall, which was primarily long-range transported.     

Evaluation of Potential Molecular Markers for Urban Stormwater Runoff

Source specificity and persistence of several sulfur-polycyclic aromatic hydrocarbons (S-PAHs), nitro-PAHs (N-PAHs), and triphenylene were examined via analyses of stormwater runoff and wastewater effluent samples and spiked samples upon exposure to sunlight. Samples were collected during the 1997/1998 wet weather season from two major storm channels and four major wastewater treatment plants in southern California. Among the target compounds examined, 2-(4-morpholinyl)benzothiazole, dibenzothiophene, and triphenylene/chrysene were detected in storm runoff only. However, 2-(4-morpholinyl)benzothiazole appeared to degrade rapidly in seawater and sediment after sunlight exposure, which might impede its use as a runoff indicator. Dibenzothiophene and triphenylene also degraded quickly in sunlight-exposed seawater samples, but remained fairly abundant in sediments after six months of exposure to sunlight. They are by far the most promising candidates of urban runoff markers based on the criteria of abundance, source specificity, and persistence, although more research efforts are needed to ensure that no other sources would also contribute significantly to their presence in the aquatic environment.     

Bacterial degradation of acetone in an outdoor model stream

Diurnal variations of the acetone concentration in an outdoor model stream were measured with and without a nitrate supplement to determine if the nitrate supplement would stimulate bacterial degradation of the acetone. Acetone loss coefficients were computed from the diurnal data using a fitting procedure based on a Lagrangian particle model. The coefficients indicated that bacterial degradation of the acetone was occurring in the downstream part of the stream during the nitrate addition. However, the acetone concentrations stabilized at values considerably above the limit of detection for acetone determination, in contrast to laboratory respirometer studies where the acetone concentration decreased rapidly to less than the detection limit, once bacterial acclimation to the acetone had occurred. One possible explanation for the difference in behavior was the limited 6-hour residence time of the acetone in the model stream.     

Some properties of calcium-activated adenosine triphosphatase from the hermatypic coralGalaxea fascicularis

Samples of the hermatypic coralGalaxea fascicularis were collected between April 1987 and April 1990 from coral reefs off Singapore (103 °45E; 1 °13N). Ca²⁺-activated adenosine triphosphatase (ATPase) activity was detected in the plasma-membrane-enriched heavy microsomal fraction ofG. fascicularis. The high affinity component hadKm andVmax values of 0.0021 mM and 0.050 µmol Pi mg^–1 protein min^–1, respectively; corresponding values for the low affinity component were 0.15 mM and 0.85 µmol mg^–1 protein min^–1. The activity of the high affinity component was inhibited 80 and 50%, respectively, by the anticalmodulin drugs calmidazolium and chlorpromazine. The low affinity component of the Ca²⁺-ATPase may represent activities of alkaline phosphatase, Ca²⁺-ATPase from membranes of mitochondria and endoplasmic reticulum, or calmodulin-dissociated plasma membrane Ca²⁺-ATPase resulting from the removal of Ca²⁺ by EDTA during the isolation process. The high affinity Ca²⁺-ATPase is probably the enzyme responsible for Ca²⁺ extrusion from the cells ofG. fascicularis. The high and low affinity components of this Ca²⁺-ATPase could use ATP and ADP as substrates. Maximum activities of both components were registered at pH 7 and at 45°C. Ruthenium red, a specific inhibitor of Ca²⁺-ATPase, inhibited the activities of the high and low affinity Ca²⁺-ATPase by 100 and 60%, respectively. Inhibition of the activities of both components was also observed with sulphydryl reagents (PCMB and mersalyl). However, DCMU, diamox, dinitrophenol, iodoacetate, fluoride, cyanide, ouabain, oligomycin B and L-phenylalanine had no effect on the enzyme activities.     

ANALYSIS OF STREAMFLOW TRENDS AND THE EFFECTS OF CLIMATE IN PENNSYLVANIA, 1971 TO 20011

An understanding of temporal trends in total stream‐flow (TSF), base flow (BF), and storm runoff (RO) can help in the development of water management plans for watersheds and local communities. In this study, 47 streams across Pennsylvania that were unregulated and unaffected by karst environments or coal mining were studied for flow trends and their relationships to selected climate parameters for the period 1971 to 2001. LOWESS curves for annual flow showed that almost all of the selected streams in Pennsylvania had downward trends in total TSF, BF, and RO. Using a seasonal Mann‐Kendall analysis, downward trends were significant at an α= 0.05 level for 68, percent 70 percent, and 62 percent of the streams and at an α= 0.10 level for another 19, 17, and 13 percent of the streams for TSF, BF, and RO, respectively. The ratio of BF to TSF (RBS) had significant upward trends for 34 percent of the streams at an α= 0.05 level and for another 9 percent of the streams at an α= 0.10 level, indicating that TSF decreased relative to BF for more than 40 percent of the streams during the previous 30 years. Downward trends in TSF, BF, and RO were most common for the months of June, July, and December. Trend analyses using monthly and annual total precipitation and mean temperature showed some association between climate and the streamflow trends, but Spearman's correlation and partial Mann‐Kendall analyses revealed that the trends in TSF, BF, and RO could not be explained by trends in precipitation and temperature alone, and thus urbanization and development may have played a role.