The Effects of Freeze–Thaw Cycles on Methane Emissions From Peat Soils of a High-Altitude Peatland

The Qinghai– Tibet Plateau (QTP), which embodies the largest area of permafrost at mid–low altitudes world, has been experiencing rapid degradation and changes in freeze–thaw processes for past decades. However, responses potential feedbacks methane flux from peatlands on QTP to changing cycles (FTCs) remain unknown. In this study, we collected peat soils Zoîgé peatlands, peatland complex QTP, examine emissions under simulated diurnal FTC scenarios. incubation experiments 15 days, two temperature ranges −5 4°C (mild) −15 (intense) were applied sets soil samples, each them was characterized by 100% or 80% maximum water holding capacity (MWHC). results showed that peak emission occurred after first cycle (FTC1), with highest reaching a value 0.103 mg kg −1 ·h . Generally, cumulative elevated FTCs, relative higher rates found 2nd 15th FTC, compared those low-altitude peatlands. Methane significantly correlated export dissolved organic carbon (DOC) activities β -D-cellobiosidase phenol oxidase various conditions. This study highlights importance FTCs stimulating implies during high-altitude would increase warmer climate future.