Incidence and severity of Phoracantha-induced decline within high-elevation eucalypt woodlands are strongly associated with elevation and land management

作者：Matthew Brookhouse, Roger Farrow, J. Y. Meyer, Keith L. McDougall, Jessica Ward‐Jones, Genevieve T. Wright · 发表于：Forest Ecology and Management · 年份：2024 · DOI：10.1016/j.foreco.2024.121872 · 被引用次数：6 · 研究领域：Forest Insect Ecology and Management、Fire effects on ecosystems、Forest Ecology and Biodiversity Studies

Observations suggest that sudden canopy decline and death of widely dispersed individual trees, associated with wood-borer infestations, has recently expanded and intensified within high-elevation Eucalyptus pauciflora and E. lacrimans stands on the Kosciuszko massif, southeast Australia. Despite reports of insect infestations and associated tree decline over four decades, the phenomenon has been poorly understood and the identity of the associated wood-borer taxon only anecdotally resolved. We conducted a systematic study of sub-alpine forests in Kosciuszko National Park, NSW, with the intent of building a knowledge base of the phenomenon’s aetiology and guiding ongoing research priorities. Using 10-metre radius plots positioned on elevational transects in areas under shared management for snow-based recreation and conservation and areas managed for conservation-only, we found a strong association between increasing severity of wood-borer feeding galleries and decline of canopy condition. The presence of even the first indicators of insect infestation was associated with a three-fold increase in declining canopy condition. Two-way contingency analysis revealed that increasing severity of feeding galleries corresponded with a highly significant decline in canopy-condition. Indicators of wood-borer infestation held greater explanatory power for deteriorating crown condition, than the converse, indicating that wood-borer infestation more likely precede, than follow, canopy decl...