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  1. 4 Polish Polar Research

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  1. 4 Walker T. R.

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  1. 1 2008

  2. 3 2005

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1

Comparison of anthropogenic metal deposition rates with excess soil loading from coal, oil and gas industries in the Usa River Basin, NW Russia

100%
Walker T. R.
Polish Polar Research
|
2005
|
tom 26
|
nr 4
299-314
Trace metal composition of snowpack, snow-melt filter residues and top-soils were determined along transects through industrial towns in the Usa River Basin: Inta, Usinsk and Vorkuta. Elevated concentrations of deposition elements and pH in snow and soils associated with alkaline coal ash within 25-40 km of Vorkuta and Inta were found. Atmospheric deposition in the vicinity of Vorkuta and Inta, added significantly to the soil contaminant loading as a result of ash fallout. The element concentrations in soils within 20-30 km of Vorkuta do not reflect current deposition rates, but instead, reflect an historical pollution legacy, when coal mining activity peaked in the 1960s. There is little evidence of anthropogenic metal deposition around the gas and oil town of Usinsk.
2

Zinc accumulation in lichens due to industrial emissions around Vorkuta, northeast European Russia

100%
Walker T. R.
Polish Polar Research
|
2008
|
tom 29
|
nr 2
141-147
Zinc concentrations in apices [Zn 2+]apex of the lichens, Cladonia arbuscula and C. rangiferina were determined along transects through two sub-Arctic towns in the Usa River Basin, northeast European Russia. One transect, which was 130 km long running in an east-west direction, passed through the town of Vorkuta and the other transect, which was 240 km long running in a southwest-northeast direction, passed through Inta. Zinc accumulation in lichens, which was detected 25-40 km within the vicinity of Vorkuta, was largely attributed to local emissions of alkaline coal ash from coal combustion. The present results using C. arbuscula around Vorkuta are consistent with those of previous studies suggesting that this lichen is a useful bioindicator for trace metals. There was no such elevation of [Zn 2+]apex detected in C. rangiferina along the transect running through Inta.
3

Vertical organic inputs and bio-availability of carbon in an Antarctic coastal sediment

100%
Walker T. R.
Polish Polar Research
|
2005
|
tom 26
|
nr 2
91-106
Measurements were made of organic fluxes at a coastal sediment at Signy Island, South Orkney Islands, Antarctica, between December 1990 and March 1992. The deposition rate of organic matter to the sediment was measured at the same time with a maximum sedimentation rate of 306 mg C m-2 d-1. The rates of sedimentary organic input were small during winter ice cover, and the organic content of the sediment declined during this period as available organic matter was depleted. Fresh organic input occurred as soon as the sea-ice melted and ice algal biomass was deposited to the sediment; and was sustained during the spring after ice break-up by continued primary production in the water column. The proportion of available carbon in surface sediments was measured during a seasonal cycle using Pseudomonas aeruginosa as an indicator organism over the 0-1 cm depth horizon. Variations in the amount of organic matter deposited to the sediments and the proportion of available carbon were observed during the seasonal cycle. Seasonal variations of benthic activity in this coastal sediment was regulated by the input and availability of organic matter, and not by seasonal water temperature, which was relatively constant between -1.8 and 0.5 C.
4

Distribution of oxygen, sulfides and optimum temperature for sulfate reduction in Antarctic marine sediments

100%
Walker T. R.
Polish Polar Research
|
2005
|
tom 26
|
nr 3
215-230
Measurements were made of sediment characteristics, benthic microbial activity and optimum temperature for sulfate reduction at Signy Island, South Orkney Islands, Antarctica. There was little evidence to support any seasonal variation in oxygen penetration of surface sediments. Oxygen penetrated to only 1.5 to 3 mm throughout the year, despite bioturbation from a dense amphipod population. The distribution of acid volatile sulfides increased with depth below 1 cm and above this, surface sediments were lighter in colour and contained fewer sulfides. The rates of sulfate reduction increased during winter under sea-ice cover, and remained high after ice break up. Seasonal water temperature was relatively constant between -1.8 and 0.5°C. Optimum temperature for anaerobic sediment respiration was investigated using different substrates and was found to be in the range 17-27°C, suggesting that sulfate reducing bacteria are psychrotolerant as they were inhibited by low temperatures.
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