Differences in the intensity of past forest fire events inferred from stable oxygen isotope analysis of charred bark.

IF 1.7 3区农林科学 Q2 FORESTRY

Canadian Journal of Forest Research Pub Date : 2024-07-15 DOI:10.1139/cjfr-2024-0025

Tegan McWhirter, Elizabeth Webb, Jeffery P Dech

{"title":"Differences in the intensity of past forest fire events inferred from stable oxygen isotope analysis of charred bark.","authors":"Tegan McWhirter, Elizabeth Webb, Jeffery P Dech","doi":"10.1139/cjfr-2024-0025","DOIUrl":null,"url":null,"abstract":"Understanding past fire regimes requires reliable proxy data that record fire conditions and preserve them over time. The objective of this study was to determine if the oxygen isotope composition of charred bark samples (pyrogenic organic matter) could be used as proxy data to differentiate wildfires based on burn intensity. We collected charred and uncharred bark samples from three fire sites in northern Ontario, Canada that represented a gradient of fire intensity as depicted by Fire Weather Index (FWI) data. We hypothesized that the mean Δ18Obark-char (the difference between δ18O of uncharred bark and a charred sample) would be greater for fires with higher intensities. Analysis of variance of Δ18Obark-char indicated a significant effect of fire event (F=73.6, p<0.001), which explained 57.0 % of the variance. A prescribed surface fire treatment (mean FWI = 9.5) had significantly lower Δ18Obark-char than two natural crown fires (FWI = 21 and 27). These results demonstrate that Δ18Obark-char differentiated moderate from high intensity fires in a similar manner to the FWI data.","PeriodicalId":9483,"journal":{"name":"Canadian Journal of Forest Research","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Canadian Journal of Forest Research","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1139/cjfr-2024-0025","RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"FORESTRY","Score":null,"Total":0}

引用次数: 0

Abstract

Understanding past fire regimes requires reliable proxy data that record fire conditions and preserve them over time. The objective of this study was to determine if the oxygen isotope composition of charred bark samples (pyrogenic organic matter) could be used as proxy data to differentiate wildfires based on burn intensity. We collected charred and uncharred bark samples from three fire sites in northern Ontario, Canada that represented a gradient of fire intensity as depicted by Fire Weather Index (FWI) data. We hypothesized that the mean Δ18Obark-char (the difference between δ18O of uncharred bark and a charred sample) would be greater for fires with higher intensities. Analysis of variance of Δ18Obark-char indicated a significant effect of fire event (F=73.6, p<0.001), which explained 57.0 % of the variance. A prescribed surface fire treatment (mean FWI = 9.5) had significantly lower Δ18Obark-char than two natural crown fires (FWI = 21 and 27). These results demonstrate that Δ18Obark-char differentiated moderate from high intensity fires in a similar manner to the FWI data.

查看原文本刊更多论文

从烧焦树皮的稳定氧同位素分析推断过去森林火灾事件强度的差异。

要了解过去的火灾机制，需要可靠的替代数据来记录火灾情况并长期保存。本研究的目的是确定烧焦的树皮样本（热原有机物）的氧同位素组成是否可用作替代数据，根据燃烧强度来区分野火。我们从加拿大安大略省北部的三个火灾现场采集了烧焦和未烧焦的树皮样本，这些样本代表了火灾强度的梯度，正如火灾气象指数（FWI）数据所描述的那样。我们假设，火灾强度越高，平均Δ18Obark-char（未炭化树皮与炭化样本的 Δ18O之差）就越大。Δ18Obark-char的方差分析表明，火灾事件有显著影响（F=73.6，p<0.001），解释了57.0%的方差。与两场自然冠火（FWI = 21 和 27）相比，一场规定的地表火（平均 FWI = 9.5）的Δ18Obark-char 明显较低。这些结果表明，Δ18Obark-char 能以与 FWI 数据类似的方式区分中等强度和高强度火灾。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Canadian Journal of Forest Research 农林科学-林学

CiteScore

4.20

自引率

9.10%

发文量

109

审稿时长

3 months

期刊介绍： Published since 1971, the Canadian Journal of Forest Research is a monthly journal that features articles, reviews, notes and concept papers on a broad spectrum of forest sciences, including biometrics, conservation, disturbances, ecology, economics, entomology, genetics, hydrology, management, nutrient cycling, pathology, physiology, remote sensing, silviculture, social sciences, soils, stand dynamics, and wood science, all in relation to the understanding or management of ecosystem services. It also publishes special issues dedicated to a topic of current interest.