Brassard François, Murphy Brett P, Ferrier Simon, Andersen Alan N
Research Institute for the Environment and Livelihoods, Charles Darwin University, Ellengowan Drive, Casuarina, Darwin, NT, 0810, Australia.
Commonwealth Scientific and Industrial Research Organisation, GPO Box 1700, Canberra, ACT, 2601, Australia.
Oecologia. 2025 Feb 28;207(3):41. doi: 10.1007/s00442-025-05683-7.
The hypothesis that pyrodiversity begets biodiversity is foundational to conservation management in fire-prone ecosystems and has received extensive research attention. However, empirical evidence for the hypothesis remains ambivalent. Moreover, few studies directly assess the key question of how much pyrodiversity is needed to conserve all species within a community. A novel way of addressing this is to use the biodiversity-maximisation approach developed for reserve selection as part of strategic conservation planning. We apply this approach to an ant dataset from a long-term fire experiment in northern Australia to establish how many of the six experimental fire treatments are required to represent all local ant diversity. We identified the treatment combinations required to maximise species richness and geometric mean abundance. We repeated this for six fire-activity classes based on cumulative fire intensity experienced by plots over the course of the experiment. We found that a very limited number of fire treatments or fire activity classes were needed to represent all of the highly diverse ant species and to maximise the geometric mean abundance of ants. We attribute this to the substantial small-scale heterogeneity of fire behaviour and vegetation structure within individual fire treatments. We conclude that high pyrodiversity at larger spatial scales is not required for sustaining ant biodiversity in our study system. We believe that a reserve selection approach is a powerful method for assessing how much pyrodiversity is needed to conserve biodiversity and recommend that it be applied to other taxa and other ecosystems.
火多样性孕育生物多样性这一假说，是易发生火灾的生态系统保护管理的基础，并且已受到广泛的研究关注。然而，该假说的实证证据仍然模棱两可。此外，很少有研究直接评估需要多少火多样性才能保护群落中的所有物种这一关键问题。解决这个问题的一种新方法是使用为保护区选择而开发的生物多样性最大化方法，作为战略保护规划的一部分。我们将这种方法应用于澳大利亚北部一项长期火灾实验的蚂蚁数据集，以确定六种实验性火灾处理中需要多少种来代表所有当地蚂蚁的多样性。我们确定了使物种丰富度和几何平均丰度最大化所需的处理组合。我们根据实验过程中地块经历的累积火灾强度，对六个火灾活动类别重复了这一过程。我们发现，只需非常有限数量的火灾处理或火灾活动类别，就能代表所有高度多样的蚂蚁物种，并使蚂蚁的几何平均丰度最大化。我们将此归因于各个火灾处理中火灾行为和植被结构存在大量的小尺度异质性。我们得出结论，在我们的研究系统中，维持蚂蚁生物多样性不需要在更大空间尺度上具有高火多样性。我们认为，保护区选择方法是评估保护生物多样性需要多少火多样性的一种有力方法，并建议将其应用于其他分类群和其他生态系统。
