Occurrence of Arbuscular Mycorrhizal Fungi across a Range of Alpine Humus Soil Conditions in Kosciuszko National Park, Australia

Abstract

The occurrence of arbuscular mycorrhizal fungi (AMF) was examined in tall alpine herbfields (Celmisia-Poa alliance) in Kosciuszko National Park, Australia. Relatively undisturbed areas and areas which had been successfully, and unsuccessfully, rehabilitated in the 1960s and 1970s following severe loss of vegetation and soil erosion were sampled. Most common plant species in undisturbed areas were colonized by AMF, often with greater than 50% of root length colonized. Colonization by AMF of the dominant species, Poa fawcettiae, was substantially lower in areas that had failed to re-establish vegetation or a soil profile following rehabilitation, and in areas that had been successfully rehabilitated, but had again started to degrade in the 1990s. This lower colonization may be attributed to a number of factors. These include toxic effects from Zn released from galvanized wire used in the rehabilitation work and the loss of the organic horizon resulting in reduced AMF inoculum levels, extreme soil temperatures and low soil water. The study indicated that AMF might need to be considered when planning the rehabilitation of degraded areas of herbfields in Kosciuszko National Park.