Author(s): Yiming Zhao; Xiaoqiang Chen; Wenfeng Huang; Zhijun Li

Linked Author(s): Zhijun Li, Yiming Zhao, Xiaoqiang Chen

Keywords: Ice-cover; Reservoir; Greenhouse gas; Spatial heterogeneity

Abstract: Ice-covered periods represent a critical but understudied phase in reservoir greenhouse gas (GHG) dynamics. Yet little is known about how seasonal ice cover alters the relative accumulation patterns of CH4, CO2, and N2O across hydrologically distinct reservoir zones. Here, we conducted a multi-depth investigation covering both the ice-covered and open-water periods in a seasonal ice-covered reservoir to evaluate the spatiotemporal distributions and environmental impacts of dissolved CH4, CO2, and N2O. Our results reveal strikingly different accumulation behaviors among the three gases during ice-covered periods: CH4 exhibited extreme buildup near the ice–water interface in lacustrine zones, while CO2 and N2O accumulated predominantly in bottom waters across all regions. During the open-water period, depth and temperature jointly regulate the CH4 concentration, while during the ice-covered period, these relationships disappear. In contrast, the controls on CO2 and N2O strongly governed by nutrient availability and chemical conditions throughout the sampling period. Compared with open-water seasons, ice cover not only intensified gas-specific accumulation but also shifted the dominant environmental controls, indicating distinct regulatory pathways for each GHG under winter isolation. These findings highlight the need to incorporate winter-specific processes into regional and global emission assessments.

DOI:

Year: 2026