Soil Chemistry data collected from the Windmill Islands, February 2019

A total of 93 soil samples was collected from 3 remote sites (Browning Peninsula, Mitchell Peninsula, Robinson Ridge) in Windmill Islands, Eastern Antarctica. A standard sampling design was applied across 3 sites where soils in the subsoil layer (3-10cm) were collected from three transects, 2 m apart, with samples taken at variable lag distances of 0, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50, 100, 100.1, 100.2, 100.5, 101, 102, 105, 110, 120, 150, 200, 200.1, 200.2, 200.5, 201, 202, 205, 210, 220, 250 and 300 m. A subsample of 18 samples (Samples at 6x points 0, 2, 100, 102, 200, 202 of each transect) were selected for a biodiversity project to study what ecological drivers along the natural environmental gradient in each site, shape the local microbial community structure. For each of the 18 samples, gDNA was subjected to Illumina sequencing (16S, A16S, 18S) post extraction in triplicates with the FastDNA SPIN kit. The sequencing run is still in progress and data will thus, be available later in Nov/Dec 2021. A suite of environmental analyses was performed on these selected 18 samples. The environmental analyses conducted include determining the dry matter fraction of each sample, and measuring the pH and conductivity using a 1:5 soil:water extract. The soil:water extract was also used to determine concentration of water-extractable chemicals (Cl, NO2, NO3, Br, PO4, SO4, NH3) via ion chromatography. Nitrogen species (NO3, NH3) obtained with potassium chloride extract and bicarbonate extractable PO4 were also included. Measurement of major elemental concentrations (SiO2, TiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, K2O, P2O5, SO3, F, Cl, V2O5, Cr2O3, Mn3O4, NiO, CuO, ZnO, SrO, ZrO2, BaO) were performed using X-ray fluorescence (XRF) analysis. Total Kjeldahl digested phosphorus and nitrogen were measured as well as total carbon, hydrogen, nitrogen and sulphur by combustion. Micronutrients (P, K, Ca, Mg, Zn, B, S, Cu, Fe, Mn, Na) relative to the cation exchange capacity (CEC) of the samples were measured using a Melich-3 extraction. Particle sizing was done via laser diffraction to differentiate the samples into three size ranges, gravel (greater than 2mm), sand (63-2000µm) and mud (less than 63µm).Given that we have performed the same set of environmental analyses on the soil samples collected from the same transect points from the same sampling area in 2005/2006, we would like to test with this 2019 dataset, whether it fits projections of a trend expected in a warming climate. On top of that, we can decipher how each site differed from each other in terms of microbial community, which is typically reflected by the difference in soil chemistry.