Scholarlink

<p>Mountain pine beetles have caused extensive tree mortality in Canadian boreal forests. In some areas, ectomycorrhizal (EM) pine stands have been replaced by arbuscular mycorrhizal (AM) vegetation. Given the distinct effects EM and AM fungi have on nutrient and carbon cycling, this study examined whether shifts in mycorrhizal dominance post-disturbance would coincide with changes in soil carbon. We predicted reduced total mineral soil carbon stocks in disturbed stands but increased carbon allocation into stable mineral-associated organic matter (MAOM). We surveyed soils and vegetation in 80 lodgepole pine-dominated sites; half disturbed 12–16&#xa0;years prior and half intact. We separated soils into MAOM and particulate organic matter (POM) to assess the size and carbon and nitrogen concentrations of each fraction. Despite distinct mycorrhizal group dominance between disturbances, disturbed forests held similar total mineral soil carbon stocks as intact sites, while C/N ratios were lower. In coarse-textured soils, disturbed sites had lower C/N in POM compared to intact sites. No differences in MAOM C/N were detected between disturbances, and the proportion of carbon stored in MAOM versus POM remained unchanged. The lower C/N of mineral soil in disturbed sites likely reflects higher-quality litters from AM vegetation. Still, the influence of mycorrhizal type on soil carbon should be interpreted cautiously, as variations in litter quality among AM species and abiotic factors could confound results. This study suggests that soil carbon stores in disturbed boreal forests are resistant, and mycorrhizal shifts alone may not substantially alter long-term soil carbon dynamics.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Over a Decade Later, Soil Carbon Stores in Boreal Forests are Resistant to Extensive Tree Mortality

  • 期刊论文

  • 发表日期：

    2025年8月28日

查看全文
  • Nicole Lau,
  • Sylvie Quideau,
  • Oleksandra Hararuk,
  • Justine Karst

摘要

Mountain pine beetles have caused extensive tree mortality in Canadian boreal forests. In some areas, ectomycorrhizal (EM) pine stands have been replaced by arbuscular mycorrhizal (AM) vegetation. Given the distinct effects EM and AM fungi have on nutrient and carbon cycling, this study examined whether shifts in mycorrhizal dominance post-disturbance would coincide with changes in soil carbon. We predicted reduced total mineral soil carbon stocks in disturbed stands but increased carbon allocation into stable mineral-associated organic matter (MAOM). We surveyed soils and vegetation in 80 lodgepole pine-dominated sites; half disturbed 12–16 years prior and half intact. We separated soils into MAOM and particulate organic matter (POM) to assess the size and carbon and nitrogen concentrations of each fraction. Despite distinct mycorrhizal group dominance between disturbances, disturbed forests held similar total mineral soil carbon stocks as intact sites, while C/N ratios were lower. In coarse-textured soils, disturbed sites had lower C/N in POM compared to intact sites. No differences in MAOM C/N were detected between disturbances, and the proportion of carbon stored in MAOM versus POM remained unchanged. The lower C/N of mineral soil in disturbed sites likely reflects higher-quality litters from AM vegetation. Still, the influence of mycorrhizal type on soil carbon should be interpreted cautiously, as variations in litter quality among AM species and abiotic factors could confound results. This study suggests that soil carbon stores in disturbed boreal forests are resistant, and mycorrhizal shifts alone may not substantially alter long-term soil carbon dynamics.