Soil temperature was monitored at 5 soil sampling times and ambient air temperature was monitored at each site throughout the field season. The sampling sites were: Bare soil at higher elevations, namely Observation Bluff, Factory Bluffs, Jane Col and lower parts of Spindrift Col; Soils from below mosses on the Backslope and on Moss Braes. Soils from below higher plant species at Bernsten Point, Factory Bluffs, Moss Braes and North Point. Orthinogenic soils from around penguin colonies at Gourlay Peninsula, Spindrift Rocks and North Point and disturbed soil from around Signy Base.

Soil fungi communities from three Antarctic islands were characterised using DNA sequencing. Between October and November 2011, soil samples were collected from Bird Island, Signy Island and Leonie Island in the sub-Antarctic, low maritime and high maritime Antarctic respectively. Soil was collected under populations of Colobanthus quitensis (Kunth) Bartl. and Deschampsia antarctica Desv., the only two native vascular plant species that occur in Antarctica. Total DNA was extracted from the soils and fungal specific primers used to amplify the ribosomal ITS region for subsequent 454 pyrosequencing. Sequences are deposited in the NCBI Sequence Read Archive (study accession SRP068654). Funding was provided by the NERC grants NE/H014098/1, NE/H014772/1 and NE/H01408X/1.

To identify and quantify soil N species over a full growth season, small volumes of soil were removed from each sampling site 5 times during the field season and extracted in the laboratory. Bare soil at higher elevations, namely Observation Bluff, Factory Bluffs, Jane Col and lower parts of Spindrift Col; Soils from below mosses on the Backslope and on Moss Braes. Soils from below higher plant species at Bernsten Point, Factory Bluffs, Moss Braes and North Point. Orthinogenic soils from around penguin colonies at Gourlay Peninsula, Spindrift Rocks and North Point and disturbed soil from around Signy Base were collected. At the same time, soil pore water was extracted using Rhizon soil water samplers. DON (Dissolved organic Nitrogen) and Microbial biomass measurements were made by standard CHCl3 fumigation-extraction techniques. Turnover of DON in the soil was determined by the addition of 14C-labelled plant protein (purified from 14C-labelled algal cells) or 14C-labelled glucose to the soil at a range of concentrations, and their turnover (soil label depletion in combination with NH4 +, NO3-and 14CO2 production) was determined. Gross rates of N mineralization and nitrification were determined using 15N isotope dilution methodology. Laboratory analysis of N speciation and quantification, 14C uptake and respiration, 13C PLFA signatures and 15N analysis was done. Amino acid turnover times have been determined using 14C labelled amino acids. For the final stage of the project a mathematical model to describe plant-soil-microbial N fluxes in Antarctic soils was constructed.

To investigate the availability of peptides in the soils on Signy Island, soil solutions were sampled throughout the summer season, from mid November 2008 until early March 2009. Soil solution samples were extracted under vacuum, with minimal disturbance to the soil, through small porous tubes. A total of 19 sites across the island were sampled in areas dominated by all the major primary producers, vascular plants, mosses, algae and lichens. The collected soil solution samples were analysed for different forms of nitrogen, including peptides.