Decomposition of non-native wood and its effects on saprotrophic fungal communities in tropical ecosystems
B.J. WIJAS , H. FLORES-MORENO, S.D. ALLISON, L.A. CERNUSAK, A.W. CHEESMAN, P. EGGLETON, J.R. POWELL, A.E. ZANNE
University of Miami, Department of Biology, 1301 Memorial Dr., Coral Gables, 33146, FL, USA

Life strategies of fungi make them one of the main contributors to decomposition of dead plant material, especially deadwood. As native forests around the globe are being replaced by plantations of non-native species, the capacity of local fungal species to decompose vegetation may be compromised, hence influencing nutrient cycling. Here, we investigated the response of deadwood fungal communities and their function as decomposers in non-native wood compared with native wood. We measured decomposition rates of 16 native species of wood and one non-native species ( Pinus radiata ) over 4 years in a tropical rainforest and savanna and assessed their fungal communities using amplicon sequencing. We found that decomposition rates of non-native pine were slower than native wood species in both ecosystems however difference in decomposition rates was higher in the rainforest (2.2 times slower) than the savanna (1.7 times slower). Concurrently, we found that fungal communities were similar in native species and pine in the savanna but not in the rainforest. Together, these results suggest that the ability of fungal saprotrophic communities to decompose non-native species is ecosystem dependent. Fungi may be more specialized and more sensitive to the introduction of non-native tree species in rainforests compared with drier savanna ecosystems.