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  • The dataset contains measurements of mean atmospheric ammonia concentrations taken at seven locations in and around Cape Hallett, northern Victoria Land. The data were obtained using ALPHA passive diffusion samplers mounted at a height of 1.5 m above ground. Samplers were exposed in triplicate at each site for three periods: 26th December 2005 to 10th January 2006, 11th to 17th and 17th to 23rd January 2006, which coincided with the penguin breeding season. Various chemical and physiological analyses of ecological materials were also conducted during the period December 2004 to January 2006, to study the effects of nitrogen enrichment on lichens. Analyses were performed on whole thalli of Umbilicaria decussata and Xanthomendosa borealis and the terminal 10-20 mm of Usnea sphacelata with Nitrogen (N), Phosphorus (P) and delta 15N values determined. Other samples analysed for N and P values include guano-rich surface soil collected from Seabee Hook to a depth of 5 mm, and an Adelie chick leg muscle, dissected from recent skua kills. Replicate values for phosphomonoesterase activity in the lichen species Usnea sphacelata, Umbilicaria decussata and Xanthomendosa borealis are listed. Lichen samples were collected from various Cape Hallett sites and analysed using the p-nitropenol phosphate method at a range of pH values.

  • In 1991 a nitrogen x phosphorus fertilisation experiment on dwarf shrub tundra close to Ny-Alesund, Svalbard was established. Treatments (0, 10, 50 kg N ha-1 yr-1; 0, 5 kg P ha-1 yr-1) were applied to Cassiope heath for 3 years and Dryas heath for 8 years. In 2011 the experiment was revisited to investigate the persistence of effects of fertilisation on species composition, vegetation nutrient status and ecosystem carbon stocks. The whole experiment has been led by Dr Sarah Woodin and colleagues, University of Aberdeen. The 2011 study, for which data are provided, was undertaken by Dr Lorna Street. Funded was provided by the NERC grant NE/I016899/1