GIS analysis, biological samples (soil microorganism, invertebrate and plant), automatic weather station data and vegetation and invertebrate surveys to determine the terrestrial biocomplexity of the McMurdo Dry Valleys
Abstract:
The McMurdo Dry Valleys are the largest area of snow-free land in Antarctica. Managers ability to promote and protect these areas would benefit if we knew the biodiversity present and what controls it distribution. The research therefore focused on describing and predicting biodiversity of terrestrial habitats in the Ross Dependency, Antarctica. The aim is to produce a GIS/biodiversity database ... that links biodiversity with environmental factors such as geology, and soil moisture content, to produce a model that is easily understood and useable by non-specialists and endusers. Samples of soil, invertebrates and mosses were collected from the Miers, Marshall, and Garwood Valleys for geochemistry and biological analysis. Over 450 sampling sites were visited although roughly 15 were inaccessible due to terrain or snow cover. A total 435 vegetation and invertebrate surveys were made and over 450 soil samples collected. At each location up-to-date molecular techniques were used to describe the biota from visible lichens, mosses and invertebrates to the hidden microbes. The soil samples were subsampled and analyses of soil geochemistry, soil respiration, microinvertebrate content (e.g. nematodes, rotifers, tardigrades), and microbiological assays. Samples were collected and split in the field using aseptic techniques for DNA analysis. New genomic approaches that examine microbial communities as a whole (i.e., metagenomics) or even their entire functional aspects (i.e., metatranscriptomics) were used to provide a comprehensive picture of systematic and functional biodiversity, which will help resolve the drivers of biodiversity in the environment. The samples are part of a major landscape scale study to determine the primary drivers of biodiversity and distribution of flora and fauna in the Dry Valleys. In addition, the SOM and other nutrient status including the form of subsidy was determined, and this information will be placed, together with site-specific variables such as aspect, slope, water, snow, stability. The use of GIS is central to the success of this project and considerable success in collating, analysing and preparing information for the GIS analysis. Two automatic weather stations were installed together with various trap systems to measure transfer of material within the Miers and Garwood Valleys in the 2007-2008 field season and in the 2008-2009 field season another was installed in the Marshall Valley.
