Published In

Antarctic Science

Document Type

Article

Publication Date

7-10-2013

Subjects

McMurdo Dry Valleys (Antarctica), Taylor Glacier (Antarctica), Antarctica -- Ecology

Abstract

Water tracks are zones of high soil moisture that route shallow groundwater down-slope, through the active layer and above the ice table. A water track in Taylor Valley, McMurdo Dry Valleys, was analysed for surface hydrogeological, geochemical, and biological characteristics in order to test the hypothesis that water tracks provide spatial structure to Antarctic soil ecosystems by changing the physical conditions in the soil environment within the water tracks from those outside the water tracks. The presence of the water track significantly affected the distribution of biotic and abiotic ecosystem parameters: increasing soil moisture, soil salinity, and soil organic matter within the water track relative to soils outside the water track, and reducing soil phosphate, soil pH, and the population of nematodes and other invertebrates in water track soils relative to off track soils. These results suggest that water tracks are distinct and extreme ecological zones in Taylor Valley that provide long-range (kilometre to multikilometre) structure to Antarctic hillslope ecosystems through physical control on soil moisture and solute content. Contrary to expectations, these high soil-moisture sites are not hotspots for faunal biological activity because high soil salinity makes them suitable habitats for only the most halo-tolerant organisms

Description

Copyright 2013 Cambridge University Press

This is the publishers PDF reproduced here with author and publisher permissions. The original publication is available at http://journals.cambridge.org

DOI

10.1017/S095410201300045X

Persistent Identifier

http://archives.pdx.edu/ds/psu/10493

Share

COinS