Department of Ecology, Environment and Evolution, La Trobe University, Bundoora, Victoria, 3086, Australia.
Research Centre for Future Landscapes, La Trobe University, Bundoora, Victoria, 3086, Australia.
Ecol Appl. 2021 Jun;31(4):e02308. doi: 10.1002/eap.2308. Epub 2021 Apr 7.
To mitigate the impact of severe wildfire on human society and the environment, prescribed fire is widely used in forest ecosystems to reduce fuel loads and limit fire spread. To avoid detrimental effects on conservation values, it is imperative to understand how prescribed fire affects taxa having a range of different adaptations to disturbance. Such studies will have greatest benefit if they extend beyond short-term impacts of burning. We used a field study to examine the effects of prescribed fire on birds and plants across a 36-yr post-fire chronosequence in a temperate dry forest ecosystem in southeastern Australia, and by making comparison with long-unburned reference sites (79 yr since wildfire). We modeled changes in the relative abundance of 22 bird species and the cover of 39 plant species, and examined how individual species, functional groups, species richness and community composition differed between sites with different fire history. For most individual bird and plant species modeled, relative abundance or cover at sites subject to prescribed fire did not change significantly with time since fire or differ from that of long-unburned vegetation. When bird species were pooled into functional groups, time since prescribed fire had strong effects on birds that forage in the lower-midstorey, facultative-resprouting shrubs and obligate-seeding shrubs. Species richness for both taxa did not differ between sites subject to prescribed fire and those in long-unburned vegetation. Bird communities varied significantly between the youngest (0-3 yr) and oldest (79 yr) post-fire age classes, driven by species associated with understorey vegetation. Plant community composition showed little evidence of a post-fire successional trajectory. The prevalence of bird species with broad habitat and dietary niches and plant regeneration through resprouting, make bird and plant communities in these forests relatively resilient to small and patchy prescribed fires they have experienced to date. Application of prescribed fire will be most compatible with maintaining biodiversity by taking a landscape approach that (1) plans for a geographic spread of stands with a range of between-prescribed-fire intervals to ensure provision of suitable habitat for all taxa, and (2) avoids burning in moist gullies to maintain their value as fire refuges.
为了减轻野火对人类社会和环境的影响,在森林生态系统中广泛采用了计划火烧来减少燃料负荷并限制火势蔓延。为了避免对保护价值产生不利影响,必须了解计划火烧如何影响具有一系列不同干扰适应能力的分类单元。如果这些研究能够超越燃烧的短期影响,将会有最大的益处。我们使用野外研究来检验澳大利亚东南部温带干旱森林生态系统中一个 36 年火后时间序列内的计划火烧对鸟类和植物的影响,并与长期未燃烧的对照点(自野火以来 79 年)进行比较。我们对 22 种鸟类的相对丰度和 39 种植物的盖度进行了建模,并研究了具有不同火烧历史的站点之间个体物种、功能群、物种丰富度和群落组成的差异。对于大多数建模的鸟类和植物物种,在受计划火烧影响的地点,相对丰度或盖度随时间的变化与火烧后时间没有显著变化,也与长期未燃烧的植被没有差异。当鸟类物种被归入功能群时,计划火烧后的时间对中层觅食的鸟类、兼性萌芽灌木和强制性种子灌木有强烈的影响。两种分类群的物种丰富度在受计划火烧影响的地点和长期未燃烧的植被之间没有差异。鸟类群落在最年轻(0-3 年)和最古老(79 年)火后年龄类之间有显著差异,这是由与林下植被相关的物种驱动的。植物群落组成几乎没有显示出火后演替轨迹的证据。具有广泛栖息地和饮食生态位的鸟类物种和萌芽再生的植物的流行,使这些森林中的鸟类和植物群落具有相对的弹性,可以适应它们迄今为止经历的小型和分散的计划火烧。通过采用景观方法来应用计划火烧,将最有利于维持生物多样性,该方法(1)规划具有一系列不同间伐间隔的林分的地理分布,以确保为所有分类单元提供合适的栖息地,以及(2)避免在潮湿的沟壑中燃烧,以保持其作为火灾避难所的价值。