Ge Mengyu, Korrensalo Aino, Laiho Raija, Lohila Annalea, Makiranta Päivi, Pihlatie Mari, Tuittila Eeva-Stiina, Kohl Lukas, Putkinen Anuliina, Koskinen Markku
Department of Agricultural Sciences, University of Helsinki, PO Box 56, Helsinki, 00014, Finland.
School of Forest Sciences, University of Eastern Finland, PO Box 111, Joensuu, 80101, Finland.
New Phytol. 2023 May;238(3):1019-1032. doi: 10.1111/nph.18798. Epub 2023 Mar 7.
Aerenchymatic transport is an important mechanism through which plants affect methane (CH ) emissions from peatlands. Controlling environmental factors and the effects of plant phenology remain, however, uncertain. We identified factors controlling seasonal CH flux rate and investigated transport efficiency (flux rate per unit of rhizospheric porewater CH concentration). We measured CH fluxes through individual shoots of Carex rostrata, Menyanthes trifoliata, Betula nana and Salix lapponum throughout growing seasons in 2020 and 2021 and Equisetum fluviatile and Comarum palustre in high summer 2021 along with water-table level, peat temperature and porewater CH concentration. CH flux rate of C. rostrata was related to plant phenology and peat temperature. Flux rates of M. trifoliata and shrubs B. nana and S. lapponum were insensitive to the investigated environmental variables. In high summer, flux rate and efficiency were highest for C. rostrata (6.86 mg m h and 0.36 mg m h (μmol l ) , respectively). Menyanthes trifoliata showed a high flux rate, but limited efficiency. Low flux rates and efficiency were detected for the remaining species. Knowledge of the species-specific CH flux rate and their different responses to plant phenology and environmental factors can significantly improve the estimation of ecosystem-scale CH dynamics in boreal peatlands.
通气组织运输是植物影响泥炭地甲烷（CH₄）排放的一种重要机制。然而，环境因素的控制以及植物物候的影响仍不确定。我们确定了控制季节性CH通量速率的因素，并研究了运输效率（单位根际孔隙水CH浓度的通量速率）。在2020年和2021年的整个生长季节，我们测量了通过喙毛茛苔草、睡菜、矮桦和拉普兰柳单个枝条的CH通量，以及在2021年盛夏测量了水木贼和沼委陵菜的CH通量，同时测量了地下水位、泥炭温度和孔隙水CH浓度。喙毛茛苔草的CH通量速率与植物物候和泥炭温度有关。睡菜以及灌木矮桦和拉普兰柳的通量速率对所研究的环境变量不敏感。在盛夏，喙毛茛苔草的通量速率和效率最高（分别为6.86 mg m⁻² h⁻¹和0.36 mg m⁻² h⁻¹（μmol l⁻¹）⁻¹）。睡菜显示出高通量速率，但效率有限。其余物种的通量速率和效率较低。了解物种特异性CH通量速率及其对植物物候和环境因素的不同反应，可显著改善对北方泥炭地生态系统尺度CH动态的估计。
Zotero 插件