Ectomycorrhizal fungal communities and soil chemistry in harvested and unharvested temperate Nothofagus rainforests

The composition of ectomycorrhizal (EcM) fungal communities in Nothofagus rainforests and the responses of the fungal communities to timber harvesting have been unknown. We investigated EcM communities in two sites, 9 to 11 years after timber harvesting, and tested whether changes in the communities were driven by soil chemistry. The fungal communities in both sites were highly diverse, yet 53 out of 140 distinct terminal restriction fragment length polymorphism (T-RFLP) patterns were shared between the sites. At both sites, timber harvesting reduced the presence of EcM roots and caused shifts in the fungal community in the organic soil horizons. At one site, Laccaria spp. increased in harvested areas, which partially correlated with an increase in soil mineralizable nitrogen. The other site showed a decreased abundance of Russula sp. (cf. R. purpureotincta, R. roseostipitata) in harvested areas, which correlated with declines in soil carbon and organic horizon depth, and a decline in the abundance of rare species at the edge of harvested areas, which was related to inorganic phosphorus. The results show that EcM fungal communities in Nothofagus temperate rainforest are highly diverse at the local scale, yet have a high degree of similarity across sites. These communities are directly affected by timber harvesting and by shifts in soil chemistry following timber harvesting.