Microorganisms play a dominant role in Antarctic ecosystems, yet little is known about how fungal diversity differs at sites with considerable human activity as compared to those that are remote and relatively pristine. Ross Island, Antarctica is the site of three historic expedition huts left by early explorers to the South Pole, Robert F. Scott and Ernest Shackleton. The fungal diversity of these wooden structures and surrounding soils was investigated with traditional culturing methods as well as with molecular methodology including denaturing gradient gel electrophoresis (DGGE) using the internal transcribed spacer (ITS) regions of ribosomal DNA for identification. From historic wood and artifact samples and soils adjacent to the huts as well as soil samples obtained from the Lake Fryxell Basin, a remote Dry Valley location, and remote sites at Mt. Fleming and the Allan Hills, 71 fungal taxa were identified. The historic huts and associated artifacts have been colonized and degraded by fungi to various extents. The most frequently isolated fungal genera from the historic woods sampled include Cadophora, Cladosporium and Geomyces. Similar genera were found in soil samples collected near the huts. Sampling of soils from locations in the Transantarctic Mountains and Lake Fryxell Basin at considerable distances from the huts and with different soil conditions revealed Cryptococcus spp., Epicoccum nigrum and Cladosporium cladosporioides as the most common fungi present and Cadophora species less commonly isolated. DGGE revealed 28 taxa not detected by culturing including four taxa which possibly have not been previously described since they have less than 50% ITS sequence identity to any GenBank accessions. Fungi capable of causing degradation in the wood and artifacts associated with the expedition huts appear to be similar to those present in Antarctic soils, both near and at more remote locations. These species of fungi are likely indigenous to Antarctica and were apparently greatly influenced by the introduction of organic matter brought by early explorers. Considerable degradation has occurred in the wood and other materials by these fungi.
Bibliographical noteFunding Information:
The authors would like to thank Shona Duncan and Joanne Thwaites of the University of Waikato, New Zealand for assistance in field work and Professor Diana Wall of Colorado State University for providing soil samples from the Lake Fryxell Basin and for organizing this special issue of Soil Biology and Biochemistry. We also thank Dr. Jason Smith Department of Plant Pathology, University of Minnesota for his help with DGGE methodology and manuscript review. We would also like to thank Nigel Watson and the Antarctic Heritage Trust for their cooperation and support, the personnel at Scott Base and McMurdo Station for their assistance in carrying out this research in Antarctica and Antarctica New Zealand for their support. This research is based upon work supported by the National Science Foundation. This project serves as partial fulfillment of the requirements for Master of Science degree at the University of Minnesota.
Copyright 2008 Elsevier B.V., All rights reserved.
- Dry valleys
- Historic huts
- Ross island