Assessment of fungal diversity and deterioration in a wooden structure at New Harbor, Antarctica

Scientists working at New Harbor, Antarctica in November 1959 used a wooden crate as a makeshift workspace and kitchen. The structure has been used intermittently over the subsequent decades and still remains at the site with various materials left in and around it. The wooden structure was assessed for deterioration and samples collected to determine the diversity of fungi at the site after 43 years in the Antarctic environment. Results from these investigations are compared to the results from research on the historic huts of Ross Island, approximately 70 km east of New Harbor that were built 48-58 years earlier. Our analysis shows the wood of the New Harbor structure is extremely weathered and soft rot decay was detected in the wood in contact with the ground. Fungal cultures isolated from wood of the structure were identified using sequences of the internal transcribed spacer region of the rDNA. Several species of Cadophora were identified including C. malorum, C. luteo-olivacea, C. fastigiata and a previously undescribed species designated C. sp. NH. Laboratory decay experiments using two Cadophora species isolated from New Harbor demonstrated extensive decay and loss of biomass in hardwood wafers after 16 weeks. Other fungi isolated from the wood included species of Cladosporium, Hormonema, Penicillium and Lecythophora. Wind erosion has also severely affected the structure's exterior wood causing deep furrowing between earlywood and latewood cells. In general, the deterioration and fungi found at the site were similar to those found at the historic expedition huts on Ross Island, however, one species obtained is unique to the New Harbor site. This research expands our knowledge of the microbes colonizing wood brought into the polar environment and provides additional information on deterioration and decomposition processes occurring in Antarctica.