Hansen Paige M, Semenova-Nelsen Tatiana A, Platt William J, Sikes Benjamin A
Department of Ecology and Evolutionary Biology and Kansas Biological Survey, University of Kansas, Lawrence, KS 66047 USA.
Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 USA.
Fungal Ecol. 2019 Dec;42. doi: 10.1016/j.funeco.2019.07.006. Epub 2019 Aug 23.
While the negative effects of infrequent, high-intensity fire on soil fungal abundance are well-understood, it remains unclear how the short-term history of frequent, low-intensity fire in fire-dependent ecosystems impacts abundance, and whether this history governs any abundance declines. We used prescribed fire to experimentally alter the short-term fire history of patches within a fire-frequented old-growth pine savanna over a 3 y period. We then quantified fungal abundance before and after the final fire using phospholipid fatty acid (PLFA) assays and Droplet Digital™ PCR (ddPCR). Short-term fire history largely did not affect total fungal abundance nor pre- to post-fire abundance shifts. While producing similar conclusions, PLFA and ddPCR data were not correlated. In addition to piloting a new method to quantify soil fungal abundance, our findings indicate that, within fire-frequented pine savannas, recurrent fires do not consistently decrease total fungal abundance, and abundance changes are not contingent upon short-term fire history. This suggests that many fungi in fire-dependent ecosystems are fire-tolerant.
虽然不频繁的高强度火灾对土壤真菌丰度的负面影响已为人熟知，但在依赖火灾的生态系统中，频繁的低强度火灾的短期历史如何影响真菌丰度，以及这段历史是否导致了真菌丰度的下降，仍不清楚。我们通过规定火烧，在3年时间里对一片经常发生火灾的老龄松树林地内的斑块短期火灾历史进行了实验性改变。然后，我们使用磷脂脂肪酸（PLFA）分析和液滴数字PCR（ddPCR）对最后一次火烧前后的真菌丰度进行了量化。短期火灾历史在很大程度上既没有影响真菌的总丰度，也没有影响火烧前后的丰度变化。虽然得出了类似的结论，但PLFA和ddPCR数据并不相关。除了试点一种量化土壤真菌丰度的新方法外，我们的研究结果表明，在经常发生火灾的松树稀树草原中，反复发生的火灾并不会持续降低真菌的总丰度，且丰度变化并不取决于短期火灾历史。这表明在依赖火灾的生态系统中，许多真菌具有耐火性。
