Phillip B. McKenna, Natasha Ufer, Vanessa Glenn, David Doley, Stuart Phinn, Peter D. Erskine
{"title":"Old Man Saltbush mortality following fire challenges the resilience of post-mine rehabilitation in central Queensland, Australia","authors":"Phillip B. McKenna, Natasha Ufer, Vanessa Glenn, David Doley, Stuart Phinn, Peter D. Erskine","doi":"10.1111/emr.12579","DOIUrl":null,"url":null,"abstract":"<p>Landscape rehabilitation following mining is required to be resilient to disturbance impacts such as fire, drought and disease. As mining companies undergo the process of rehabilitation certification and mine closure, there are notable knowledge gaps on the ecological risks associated with mature rehabilitated landscapes, based largely on the assumption that rehabilitation is analogous to reference communities. However, the response to fire disturbance across a range of landscapes remains largely untested and in particular there is limited understanding of recovery traits of plant species that occur naturally or are commonly seeded into rehabilitation. In August 2018, a controlled fire was applied to 37 hectares of 12-year-old coal-mine rehabilitation in central Queensland, Australia. We used a combination of (i) ground plot surveys and (ii) drone imagery to compare the vegetation response of burnt woody species to unburnt controls prior to, and for, two years following the fire. The survival of the most dominant shrub species found on the rehabilitation site was significantly impacted by the fire. Old Man Saltbush (<i>Atriplex nummularia</i> Lindl. subsp. <i>nummularia</i>) recorded significant post-fire mortality, with ground surveys recording an average reduction of 89% of stems per hectare across the burnt site, while unburnt controls remained unchanged. The plot data analysis was supported with high spatial and temporal resolution drone imagery, classified using a Random Forest machine-learning approach. Change analysis of these maps showed a significant decline of 82% in Old Man Saltbush plant density and 92% reduction in foliage cover following the fire. In addition, the mean canopy area of individual Old Man Saltbush shrubs reduced significantly from a pre-fire mean of 11.3 to 4.8 m<sup>2</sup> two years following the fire. A spatial proximity analysis showed that those individuals that survived the fire were located significantly closer to unburnt areas and bare spoil, indicating that discontinuous ground fuel loads can greatly improve the survivability of individuals. This study provides new evidence on the contested fire sensitivity of Old Man Salt bush and demonstrates the risk that future climate-driven extreme events may have on the resilience of novel ecosystems.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":null,"pages":null},"PeriodicalIF":16.4000,"publicationDate":"2023-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/emr.12579","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Accounts of Chemical Research","FirstCategoryId":"93","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/emr.12579","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Landscape rehabilitation following mining is required to be resilient to disturbance impacts such as fire, drought and disease. As mining companies undergo the process of rehabilitation certification and mine closure, there are notable knowledge gaps on the ecological risks associated with mature rehabilitated landscapes, based largely on the assumption that rehabilitation is analogous to reference communities. However, the response to fire disturbance across a range of landscapes remains largely untested and in particular there is limited understanding of recovery traits of plant species that occur naturally or are commonly seeded into rehabilitation. In August 2018, a controlled fire was applied to 37 hectares of 12-year-old coal-mine rehabilitation in central Queensland, Australia. We used a combination of (i) ground plot surveys and (ii) drone imagery to compare the vegetation response of burnt woody species to unburnt controls prior to, and for, two years following the fire. The survival of the most dominant shrub species found on the rehabilitation site was significantly impacted by the fire. Old Man Saltbush (Atriplex nummularia Lindl. subsp. nummularia) recorded significant post-fire mortality, with ground surveys recording an average reduction of 89% of stems per hectare across the burnt site, while unburnt controls remained unchanged. The plot data analysis was supported with high spatial and temporal resolution drone imagery, classified using a Random Forest machine-learning approach. Change analysis of these maps showed a significant decline of 82% in Old Man Saltbush plant density and 92% reduction in foliage cover following the fire. In addition, the mean canopy area of individual Old Man Saltbush shrubs reduced significantly from a pre-fire mean of 11.3 to 4.8 m2 two years following the fire. A spatial proximity analysis showed that those individuals that survived the fire were located significantly closer to unburnt areas and bare spoil, indicating that discontinuous ground fuel loads can greatly improve the survivability of individuals. This study provides new evidence on the contested fire sensitivity of Old Man Salt bush and demonstrates the risk that future climate-driven extreme events may have on the resilience of novel ecosystems.
采矿后的景观恢复需要能够抵御火灾、干旱和疾病等干扰影响。随着矿业公司经历恢复认证和矿山关闭的过程,在与成熟的恢复景观相关的生态风险方面存在显著的知识差距,这主要是基于恢复类似于参考社区的假设。然而,一系列景观对火灾干扰的反应在很大程度上仍未经过测试,尤其是对自然发生或通常被播种到恢复中的植物物种的恢复特征的了解有限。2018年8月,澳大利亚昆士兰州中部37公顷12年历史的煤矿修复工程发生受控火灾。我们使用了(i)地面调查和(ii)无人机图像的组合,来比较两次之前和之后被烧毁的木本物种对未燃烧对照的植被反应 火灾后数年。在修复现场发现的最具优势的灌木物种的生存受到火灾的严重影响。Old Man Saltbush(Atriplex nummularia Lindl.subsp.nummularia)记录了显著的火灾后死亡率,地面调查记录了整个燃烧现场每公顷树干平均减少89%,而未燃烧的对照保持不变。地块数据分析得到了高空间和时间分辨率无人机图像的支持,使用随机森林机器学习方法进行分类。对这些地图的变化分析显示,火灾后,Old Man Saltbush的植物密度显著下降了82%,树叶覆盖率下降了92%。此外,个别老人Saltbush灌木的平均树冠面积从火灾前的平均值11.3显著减少到4.8 m2二 火灾后数年。空间邻近度分析表明,那些在火灾中幸存的个体的位置明显更靠近未燃烧区域和裸露的弃土,这表明不连续的地面燃料负载可以大大提高个体的生存能力。这项研究为Old Man Salt灌木丛有争议的火灾敏感性提供了新的证据,并证明了未来气候驱动的极端事件可能对新生态系统的恢复力产生的风险。
期刊介绍:
Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance.
Accounts of Chemical Research replaces the traditional article abstract with an article "Conspectus." These entries synopsize the research affording the reader a closer look at the content and significance of an article. Through this provision of a more detailed description of the article contents, the Conspectus enhances the article's discoverability by search engines and the exposure for the research.