The carbon source-sink function of Hulun Lake, a large shallow eutrophic lake in northern China

Lakes are known to play a crucial role in the world-wide carbon cycling due to the efficient organic carbon burial as well as large amount of CO2 emissions to the atmosphere. Despite the increasing importance of understanding these processes in the context of global warming and escalating human acti...

Full description

Saved in:
Bibliographic Details
Main Authors: Fengju Zhang, Bin Xue, Shuchun Yao
Format: Article
Language:English
Published: Frontiers Media S.A. 2025-06-01
Series:Frontiers in Ecology and Evolution
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fevo.2025.1614198/full
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849471267606888448
author Fengju Zhang
Bin Xue
Shuchun Yao
author_facet Fengju Zhang
Bin Xue
Shuchun Yao
author_sort Fengju Zhang
collection DOAJ
description Lakes are known to play a crucial role in the world-wide carbon cycling due to the efficient organic carbon burial as well as large amount of CO2 emissions to the atmosphere. Despite the increasing importance of understanding these processes in the context of global warming and escalating human activities, the carbon source-sink dynamics of lakes remain elusive. In this study, we compared two approaches, a mass balance approach and the CO2 emission-carbon burial balance method to investigate the role of lake as carbon source or sink in Hulun Lake (the largest lake in northeastern China) from June 2015 to May 2016. Both approaches converged on the same conclusion that Hulun Lake was a great carbon source. With the overall mass balance calculations, total carbon input was 112.4×103 t during our study period, with the largest input was from the inlet rivers (107.5×103 t). The total carbon output was 448.2×103 t, and the CO2 emission accounted for about 99% of the output. The net carbon budget was -289×103 t, suggesting that Hulun Lake was a great carbon source. Furthermore, the total C-CO2 emission was three times higher than sediment carbon accumulation, stressing Hulun Lake was an important carbon source. The carbon source function mainly results from low primary production, long lake water residence time, high allochthonous carbon inputs (carbon derived from external terrestrial and atmospheric sources) and intensive human activities (e.g., grazing intensity up to 2.0 livestock units/ha, approaching the maximum stocking rate for Inner Mongolian grasslands). While further research is necessary to generalize these findings, our results provide compelling evidence for the significant role of lakes in the carbon cycle, and highlighting the importance of considering both carbon burial and carbon emission in assessments of the carbon sink-source function.
format Article
id doaj-art-1c7449045c13402ca67d32a4bcddbe8b
institution Kabale University
issn 2296-701X
language English
publishDate 2025-06-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Ecology and Evolution
spelling doaj-art-1c7449045c13402ca67d32a4bcddbe8b2025-08-20T03:24:53ZengFrontiers Media S.A.Frontiers in Ecology and Evolution2296-701X2025-06-011310.3389/fevo.2025.16141981614198The carbon source-sink function of Hulun Lake, a large shallow eutrophic lake in northern ChinaFengju Zhang0Bin Xue1Shuchun Yao2School of Geography, Geomatics and Planning, Jiangsu Normal University, Xuzhou, ChinaNanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, ChinaNanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, ChinaLakes are known to play a crucial role in the world-wide carbon cycling due to the efficient organic carbon burial as well as large amount of CO2 emissions to the atmosphere. Despite the increasing importance of understanding these processes in the context of global warming and escalating human activities, the carbon source-sink dynamics of lakes remain elusive. In this study, we compared two approaches, a mass balance approach and the CO2 emission-carbon burial balance method to investigate the role of lake as carbon source or sink in Hulun Lake (the largest lake in northeastern China) from June 2015 to May 2016. Both approaches converged on the same conclusion that Hulun Lake was a great carbon source. With the overall mass balance calculations, total carbon input was 112.4×103 t during our study period, with the largest input was from the inlet rivers (107.5×103 t). The total carbon output was 448.2×103 t, and the CO2 emission accounted for about 99% of the output. The net carbon budget was -289×103 t, suggesting that Hulun Lake was a great carbon source. Furthermore, the total C-CO2 emission was three times higher than sediment carbon accumulation, stressing Hulun Lake was an important carbon source. The carbon source function mainly results from low primary production, long lake water residence time, high allochthonous carbon inputs (carbon derived from external terrestrial and atmospheric sources) and intensive human activities (e.g., grazing intensity up to 2.0 livestock units/ha, approaching the maximum stocking rate for Inner Mongolian grasslands). While further research is necessary to generalize these findings, our results provide compelling evidence for the significant role of lakes in the carbon cycle, and highlighting the importance of considering both carbon burial and carbon emission in assessments of the carbon sink-source function.https://www.frontiersin.org/articles/10.3389/fevo.2025.1614198/fullcarbon budgetmass balancecarbon evasioncarbon burialHulun Lake
spellingShingle Fengju Zhang
Bin Xue
Shuchun Yao
The carbon source-sink function of Hulun Lake, a large shallow eutrophic lake in northern China
Frontiers in Ecology and Evolution
carbon budget
mass balance
carbon evasion
carbon burial
Hulun Lake
title The carbon source-sink function of Hulun Lake, a large shallow eutrophic lake in northern China
title_full The carbon source-sink function of Hulun Lake, a large shallow eutrophic lake in northern China
title_fullStr The carbon source-sink function of Hulun Lake, a large shallow eutrophic lake in northern China
title_full_unstemmed The carbon source-sink function of Hulun Lake, a large shallow eutrophic lake in northern China
title_short The carbon source-sink function of Hulun Lake, a large shallow eutrophic lake in northern China
title_sort carbon source sink function of hulun lake a large shallow eutrophic lake in northern china
topic carbon budget
mass balance
carbon evasion
carbon burial
Hulun Lake
url https://www.frontiersin.org/articles/10.3389/fevo.2025.1614198/full
work_keys_str_mv AT fengjuzhang thecarbonsourcesinkfunctionofhulunlakealargeshalloweutrophiclakeinnorthernchina
AT binxue thecarbonsourcesinkfunctionofhulunlakealargeshalloweutrophiclakeinnorthernchina
AT shuchunyao thecarbonsourcesinkfunctionofhulunlakealargeshalloweutrophiclakeinnorthernchina
AT fengjuzhang carbonsourcesinkfunctionofhulunlakealargeshalloweutrophiclakeinnorthernchina
AT binxue carbonsourcesinkfunctionofhulunlakealargeshalloweutrophiclakeinnorthernchina
AT shuchunyao carbonsourcesinkfunctionofhulunlakealargeshalloweutrophiclakeinnorthernchina