Emerald ash borer (EAB; Agrilus planipennis Farimaire) has been found in 35 US states and five Canadian provinces. This invasive beetle is causing widespread mortality to ash trees (Fraxinus spp.), which are an important timber product and ornamental tree, as well as a cultural resource for some Tribes. The damage will likely continue despite efforts to impede its spread. Further, widespread and rapid ash mortality as a result of EAB is expected to alter forest composition and structure, especially when coupled with the regional effects of climate change in post-ash forests. Thus, we forecasted the long-term effects of EAB-induced ash mortality and preemptive ash harvest (a forest management mitigation strategy) on forested land across a 2-million-hectare region in northern Wisconsin. We used a spatially explicit and spatially interactive forest simulation model, LANDIS-II, to estimate future species dominance and biodiversity assuming continued widespread ash mortality. We ran forest disturbance and succession simulations under historic climate conditions and three downscaled CMIP5 climate change projections representing the upper bound of expected changes in precipitation and temperature. Our results suggest that although ash loss from EAB or harvest resulted in altered biodiversity patterns in some stands, climate change will be the major driver of changes in biodiversity by the end of century, causing increases in the dominance of southern species and homogenization of species composition across the landscape.

在美国的35个州和加拿大的五个省中发现了翡翠ash虫（EAB；Agrilus planipennis Farimaire）。这种侵入性的甲虫正在给灰树造成广泛的死亡（Fraxinusspp。），这是重要的木材产品和观赏树木，也是某些部落的文化资源。尽管努力阻止其扩散，但破坏可能仍会继续。此外，预计由于EAB而导致的广泛而快速的灰烬死亡率将改变森林的组成和结构，特别是当其与灰烬后森林中气候变化的区域影响相结合时。因此，我们预测了EAB诱发的灰烬死亡率和先发制粉灰收获（森林管理减缓策略）对威斯康星州北部200万公顷地区的林地的长期影响。我们使用空间明确和空间互动的森林模拟模型LANDIS-II来估算未来物种的优势地位和生物多样性，假设灰烬持续死亡。我们在历史气候条件下进行了森林扰动和演替模拟，并进行了三个降级的CMIP5气候变化预测，分别代表了降水和温度的预期变化上限。我们的结果表明，尽管EAB或收成造成的灰分流失导致某些林分的生物多样性模式发生了变化，但到本世纪末，气候变化将成为生物多样性变化的主要驱动力，从而导致南部物种的优势度增加以及物种组成的均质化整个景观。