Biogenic volatile organic compounds (bVOCs) play important roles in ecological interactions and Earth system processes, yet the biological and physical processes that drive soil bVOC exchanges remain poorly understood. In temperate forests, nearly all tree species associate with arbuscular mycorrhizal (AM) or ectomycorrhizal (ECM) fungi. Given well‐established differences in soil biogeochemistry between AM‐dominated and ECM‐dominated stands, we hypothesized that bVOC exchanges with the atmosphere would differ between soils from the two stand types. We measured bVOC fluxes at the soil‐atmosphere interface in plots dominated by AM‐ and ECM‐associated trees in a deciduous forest in south‐central Indiana, USA during the early and late vegetative growing season. Soils in both AM‐ and ECM‐dominated plots were a net bVOC sink following leaf‐out and were a greater bVOC sink or smaller source at warmer soil temperatures (T_s). The flux of different bVOCs from ECM plots was often related to soil water content in addition to T_s. Methanol dominated total bVOC fluxes, and ECM soils demonstrated greater uptake relative to AM‐dominated plots, on the order of 170 nmol m⁻² hr⁻¹ during the early growing season. Our results demonstrate the importance of soil dynamics characterized by mycorrhizal associations to bVOC dynamics in forested ecosystems and emphasize the need to study bidirectional soil bVOC uptake and emission processes.

中文翻译：

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阔叶混交林中土壤生物挥发性有机化合物的通量：温暖温度下的净吸收和菌根协会的重要性

生物挥发性有机化合物（bVOC）在生态相互作用和地球系统过程中起着重要作用，但是驱动土壤bVOC交换的生物和物理过程仍然知之甚少。在温带森林中，几乎所有树种都与丛枝菌根（AM）或外生菌根（ECM）真菌相关。鉴于AM为主和ECM为主的林分之间土壤生物地球化学的公认差异，我们假设两种林分之间的土壤中bVOC与大气的交换会有所不同。在植物生长早期和晚期，我们在美国印第安纳州中南部的落叶林中以AM和ECM相关树为主的样地中，测量了土壤-大气界面处的bVOC通量。T _s）。除了T _s之外，ECM图中不同bVOC的通量通常还与土壤含水量有关。甲醇主导的总bVOC通量，相对于AM主导的农田，ECM土壤表现出更大的吸收，在生长早期，其吸收量为170 nmol m ^-2  hr ^-1。我们的结果证明了以菌根关联为特征的土壤动力学对森林生态系统中bVOC动力学的重要性，并强调了研究双向土壤bVOC吸收和排放过程的必要性。