Characteristics of the presence and migration patterns of DOM between ice and water in the cold and arid Daihai Lake

Ting Pan; Yimeng Zhang; Fang Yang; Haiqing Liao; Weiying Feng; Fuhong Sun; Weilong Jiang; Qianqian Wang; Meichen Ji; Chenglei Yang; Matti Leppäranta

doi:10.1016/j.scitotenv.2024.170876

Characteristics of the presence and migration patterns of DOM between ice and water in the cold and arid Daihai Lake

Sci Total Environ. 2024 Apr 10:920:170876. doi: 10.1016/j.scitotenv.2024.170876. Epub 2024 Feb 15.

Authors

Ting Pan¹, Yimeng Zhang², Fang Yang³, Haiqing Liao⁴, Weiying Feng⁵, Fuhong Sun¹, Weilong Jiang¹, Qianqian Wang¹, Meichen Ji¹, Chenglei Yang⁶, Matti Leppäranta⁷

Affiliations

¹ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
² State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; Shandong Huankeyuan Environmental Engineering Co., Ltd, Jinan 250000, China.
³ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China. Electronic address: yang.fang@craes.org.cn.
⁴ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China. Electronic address: liaohq@craes.org.cn.
⁵ School of Space and Environment, Beihang University, Beijing 100191, China.
⁶ Shandong Huankeyuan Environmental Engineering Co., Ltd, Jinan 250000, China.
⁷ Institute for Atmospheric and Earth System Research, University of Helsinki, 00014 Helsinki, Finland.

PMID: 38367733
DOI: 10.1016/j.scitotenv.2024.170876

Abstract

Seasonal ice cover plays a crucial role in shaping the physical characteristics of lakes in cold and arid regions. Moreover, the ice significantly affects the level and quality of dissolved organic matter (DOM) in the water column. We utilized spectroscopy and mass spectrometry to analyze the molecular composition and distribution of DOM in ice cores and under-ice water in Daihai Lake. We identified the main environmental factors affecting DOM migration through structural equation modelling (SEM). The freezing process created a repulsive effect on DOM, with water samples demonstrating a greater DOM content than ice. The dominant part of the DOM in the ice cores was mainly comprised of protein-like materials (71.45 %), whereas water consisted of humus-like materials (54.81 %). The average molecular weight of the ice cover DOM (m/z = 396.77) was smaller than in the under-ice water (m/z = 405.42). While low-molecular and low-aromatic protein-like material tended to be trapped in the ice layer during ice formation, large-molecular and highly aromatic humic substances were more easily expelled into the water. Interestingly, condensed aromatic hydrocarbons were found to occur less frequently in the ice phase (11 %) compared to the aqueous phase (13 %). Both the lipid and protein/aliphatic compound structures exhibited slightly higher ratios in the ice (6 % and 8 %, respectively) than in water (1 % and 5 %, respectively). SEM between the ice cover environment and DOM indicated that the ice can influence the distribution pattern of DOM through the regulation of internal solute factors and other chemicals. The nature of the DOM and the rate of ice growth also play critical roles in determining the distribution mechanism of DOM for ice and water. The pollutant distribution characteristics and migration patterns between ice and water are essential for comprehending environmental water pollution and promoting pollution management and protection measures in cold region lakes.

Keywords: Dissolved organic matter; FT-ICR MS; Frozen period; Three-dimensional excitation-emission matrix.