Puig-Gironès Roger, Brotons Lluís, Pons Pere
Departament de Ciències Ambientals, Universitat de Girona, Girona, Catalonia, Spain.
Forest Sciences Centre of Catalonia (CEMFOR-CTFC), Solsona, Catalonia, Spain.
PLoS One. 2017 Mar 29;12(3):e0173599. doi: 10.1371/journal.pone.0173599. eCollection 2017.
Wildfires play a determining role in the composition and structure of many plant and animal communities. On the other hand, climate change is considered to be a major driver of current and future fire regime changes. Despite increases in drought in many areas of the world, the effects of aridity on post-fire colonization by animals have been rarely addressed. This study aims to analyse how a regional aridity gradient affects post-fire recovery of vegetation, bird species richness and the numbers of four early to middle-successional warbler species associated with the shrub cover. The database contains bird relative abundance and environmental variables from 3072 censuses in 695 transects located in 70 recently burnt areas (1 to 11 years after wildfire) in Catalonia (Spain), which were sampled between 2006 and 2013. Generalized linear mixed models (GLMMs) showed that plant cover was affected by time since fire, aridity and forest management. However, only the highest vegetation height layer (>100 cm) recovered slower in arid areas after fire. Time since fire positively influenced bird species richness and the relative abundance of the four focal species. The post-fire recovery of Melodious (Hippolais polyglotta) and Subalpine warblers (Sylvia cantillans) was hampered by aridity. Although this was not demonstrated for Dartford (S. undata) and Sardinian warblers (S. melanocephala), their occurrence was low in the driest areas during the first three years after fire. Overall, this study suggests that future increases in aridity can affect plant regeneration after fire and slow down the recovery of animal populations that depend on understorey and shrublands. Given the recently highlighted increases in aridity and fire frequency in Mediterranean-climate regions, improved knowledge on how aridity affects ecological succession is especially necessary.
野火在许多动植物群落的组成和结构中起着决定性作用。另一方面，气候变化被认为是当前和未来火灾格局变化的主要驱动因素。尽管世界许多地区干旱加剧，但干旱对火灾后动物定居的影响却很少得到研究。本研究旨在分析区域干旱梯度如何影响火灾后植被的恢复、鸟类物种丰富度以及与灌木覆盖相关的四种中早期演替莺类物种的数量。该数据库包含了2006年至2013年间在西班牙加泰罗尼亚70个最近发生火灾的地区（火灾发生后1至11年）的695个样带中3072次鸟类普查的相对丰度和环境变量。广义线性混合模型（GLMMs）显示，植物覆盖受火灾后的时间、干旱程度和森林管理的影响。然而，只有最高植被高度层（>100厘米）在火灾后的干旱地区恢复较慢。火灾后的时间对鸟类物种丰富度和四种重点物种的相对丰度有积极影响。干旱阻碍了歌林莺（Hippolais polyglotta）和亚高山林莺（Sylvia cantillans）火灾后的恢复。虽然对于达特福德林莺（S. undata）和撒丁岛林莺（S. melanocephala）来说这一点尚未得到证实，但在火灾后的头三年里，它们在最干旱地区的出现频率较低。总体而言，本研究表明，未来干旱加剧可能会影响火灾后的植物再生，并减缓依赖林下植被和灌木丛的动物种群的恢复。鉴于最近地中海气候地区干旱和火灾频率增加的情况，尤其有必要更好地了解干旱如何影响生态演替。
