Fungal colonization on excavated prehistoric wood: Implications for in-situ display

Abstract

Excavations at the Neolithic settlement of Dispilio, Greece, have revealed significant amounts of waterlogged wood, some of which is being considered for in-situ display. This study investigated the presence of fungi and their biodeterioration patterns on the excavated material. Data will be used to assess the current threat from degradation and to aid in the design of appropriate control measures for any future display strategy. Fungi were isolated using different culture media and species were identified from slide cultures using light and fluorescence microscopy. Wood micro-morphology was examined using scanning electron and light microscopy. Seventeen fungal species were identified, all of which are typical terrestrial species, suggesting that they have developed in the exposed, post-excavation environment, rather than under waterlogged burial conditions. According to the literature many of the isolated species are potential wood deteriogens. In addition to fungi, abundant bacterial growth was observed in most samples. Microscopic examination of wood cells showed patterns of decay associated with soft-rot fungi, and tunnelling and erosion bacteria, suggesting past attack related to the waterlogged burial environment. The results obtained indicated fungal colonization of exposed timbers, presenting a potential threat to their long-term survival. Any in-situ display strategy, such as continuous or periodic water-spraying of the excavated wood, should include measures to monitor and control fungal growth.