The influence of carbon cycling on oxygen depletion in north-temperate lakes
The influence of carbon cycling on oxygen depletion in north-temperate lakes
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DOI：
10.5194/bg-20-5211-2023
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发表时间：
2023-12
期刊：
影响因子：
4.9
通讯作者：
A. Delany;R. Ladwig;C. Buelo;Ellen Albright;P. Hanson
中科院分区：
文献类型：
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作者：
A. Delany;R. Ladwig;C. Buelo;Ellen Albright;P. Hanson
抽象。夏季湖泊层化过程中的低层氧耗可导致缺氧和缺氧条件。缺氧是一种水质问题，具有许多后果，包括冷水鱼类栖息地减少，饮用水质量下降，以及沉积物中营养物质和有机碳（OC）释放增加。外来和本地的OC负荷有助于氧耗提供基板微生物呼吸，但是，它们的相对贡献，在不同的湖泊系统的氧耗仍然不确定。湖泊特征，如营养状态，水文和形态，也影响碳循环过程，并可能影响氧耗动态。为了研究碳循环对低层水体氧消耗的影响，我们使用了一个基于过程的两层湖泊模型来模拟威斯康星州六个湖泊20年（1995-2014）的日常代谢动态。物理过程和内部代谢过程包括在模型中，并被用来预测溶解氧（DO），颗粒态有机碳（POC），溶解态有机碳（DOC）。在我们对贫营养型、中营养型和富营养型湖泊的研究中，我们发现自生作用比他生作用对低湖水中氧耗的影响要重要得多。在富营养化研究湖泊中，水柱中的本地POC呼吸对贫湖氧气消耗的贡献最大。POC水柱呼吸和沉积物呼吸在中营养和贫营养研究湖泊有类似的贡献。考虑到湖泊生产力和有机碳负荷的处理和命运的呼吸源的差异进行了讨论。
Abstract. Hypolimnetic oxygen depletion during summer stratification in lakes can lead to hypoxic and anoxic conditions. Hypolimnetic anoxia is a water quality issue with many consequences, including reduced habitat for cold-water fish species, reduced quality of drinking water, and increased nutrient and organic carbon (OC) release from sediments. Both allochthonous and autochthonous OC loads contribute to oxygen depletion by providing substrate for microbial respiration; however, their relative contributions to oxygen depletion across diverse lake systems remain uncertain. Lake characteristics, such as trophic state, hydrology, and morphometry, are also influential in carbon-cycling processes and may impact oxygen depletion dynamics. To investigate the effects of carbon cycling on hypolimnetic oxygen depletion, we used a two-layer process-based lake model to simulate daily metabolism dynamics for six Wisconsin lakes over 20 years (1995–2014). Physical processes and internal metabolic processes were included in the model and were used to predict dissolved oxygen (DO), particulate OC (POC), and dissolved OC (DOC). In our study of oligotrophic, mesotrophic, and eutrophic lakes, we found autochthony to be far more important than allochthony to hypolimnetic oxygen depletion. Autochthonous POC respiration in the water column contributed the most towards hypolimnetic oxygen depletion in the eutrophic study lakes. POC water column respiration and sediment respiration had similar contributions in the mesotrophic and oligotrophic study lakes. Differences in terms of source of respiration are discussed with consideration of lake productivity and the processing and fates of organic carbon loads.