Davis Aerodrome Project (DAP) – Metazoan Biology and soil chemistry of the Davis Aerodrome site. The role of soil chemical characteristics in determining the spatial distribution of metazoan invertebrates in terrestrial

Full description

The Davis Aerodrome Project (DAP) collected a range of environmental survey data over several field seasons to support a comprehensive environmental assessment of the proposed aerodrome. This data includes flora, fauna, soils, lake ecosystem, nearshore, marine, air quality and meteorological information which has been collected by a number of different methods, and extends across the current Davis Station, proposed aerodrome and supporting infrastructure footprint (Ridge Site), previous sites considered for the aerodrome (Heidemann Valley, Adams Flat), as well as locations across the Vestfold Hills away from any of the proposed developments.
The Vestfold Hills is one of the largest ice-free coastal oases in Antarctica. Most of the soils of the Vestfold Hills are mineral in character, often with large grain size and apparently limited organic carbon content. The biology of the soils of the area has until recently been poorly known. Studies undertaken under the auspices of the Davis Aerodrome Project indicated that these soils do harbour a metazoan fauna that consists inter alia of nematodes, rotifers, tardigrades and mites. However, the factors that control the distribution of these animals are uncertain.

This metadata record refers to a dataset of selected chemical and biological characteristics of a series of samples collected from the proposed aerodrome site at Davis Research Station. The study site was chosen with two aims: (1) to determine the identity and distribution of animals at the site, and (2) to provide data that would aid in the development of a model of the distribution of the metazoan fauna that could be applied elsewhere in the Vestfold Hills.

The database is comprised of chemical and biological data for a set of soil samples collected from a grid pattern across the proposed aerodrome site. The grid was designed to look at chemical and biological variability across the site, both to determine the species present and to provide data for modelling of species' distributions. A five by twenty-five line grid was used (ie 125 samples in all), with a distance of 125 m between sampling points along both axes of the grid.

The data presented in this database includes the following aspects of soil chemistry and biology: percentage water content, percentage loss on ignition (more or less equivalent to percentage organic matter), electrical conductivity of a 1:5 soil:water extract (related to salt content of the soil), and details of metazoan animals observed in samples.

The data presented here is incomplete (as of 30/6/22). A more complete dataset will be submitted to the AADC on completion of data collection.

Latitude and longitude Resolution:
Samples site location was in general recorded with a GPS, and is therefore accurate. For some samples detailed data was not recorded, and so the target location has to be assumed. Both target and actual sample locations are listed in the dataset.

Data resolution:
The resolution of the chemical data is to the number of significant figures quoted in the dataset. However, there is no measure how much variability there would be between repeat measures on the same sample.

Date Resolution
The date sample collection is recorded. The date on which the detailed analyses were undertaken is not recorded.

Lineage

Progress Code: onGoing

Statement: The soil chemistry data presented here (water content, loss on ignition, and electrical conductivity) were obtained using standard techniques. Interpretation of such data is known to be problematic (for example, is loss on ignition entirely due to the oxidation of organic material, and is all organic material broken down at this temperature?) However, each of the datasets were obtained using a standardised technique and the datasets are internally consistent. Analysis of the biota has a number of possible problems, including: 1) Incomplete isolation of animals from the samples. The method used (flotation and isolation of the animals on a 50 micron filter) has been shown to be efficient, but animals may be missed. The implication of this concern is that the presence of a species in the sample cannot be questioned, but there is always the question of whether the apparent absence of a species is indeed absolute, or reflects incomplete isolation. 2) The taxonomy of the species present can be problematic. While some species are easy to identify, others can be more difficult. The species names given in this dataset are the most accurate that can be given at present (30/6/22). Further work will allow refinement of these names, and will be included in later versions of this database.

Notes

Purpose
This dataset records aspects of the chemistry and biology of soil samples collected from sites distributed across a gridded sampling area overlaying the proposed Davis aerodrome site. This sampling program aimed to collect base line information on micro-invertebrates inhabiting soils across the proposed aerodrome site, as well as more broadly across the Vestfold Hills, to inform environmental assessment processes being undertaken by the Davis Aerodrome and Davis Masterplan projects.