The ocean serves as a significant contributor of atmospheric Hydrogen (H₂) with indirect greenhouse effects. However, uncertainties persist regarding internal production and consumption processes of marine H₂, as well as controlling factors. Our study examined the spatial distribution and source-sink dynamics of marine H₂ in the Eastern Indian Ocean. H₂ concentrations in surface seawater exhibited a range of 2.95–21.96 nmol L⁻¹. High concentrations of H₂ were observed in the anoxic water in the Bay of Bengal. Rates of H₂ photo-production and microbial consumption in surface seawater ranged from 1.80 to 17.78 nmol L⁻¹ h⁻¹ and 1.02–9.18 nmol L⁻¹ h⁻¹, respectively. When considering the entire mixed layer, photo-production contribute to approximately 31%–43% of the total H₂ removal, with cyanobacteria potentially serving as another source in the mixed layer. Compared with the sea-to-air exchange, microbial consumption was the primary removal pathway of H₂ in seawater.

中文翻译：

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东印度洋海洋氢的分布特征与动态


海洋是大气中氢 （H₂） 的重要贡献者，具有间接的温室效应。然而，海洋 H₂ 的内部生产和消费过程以及控制因素仍然存在不确定性。我们的研究考察了东印度洋海洋 H₂ 的空间分布和源-汇动力学。表层海水中的 H₂ 浓度范围为 2.95-21.96 nmol ^L-1。在孟加拉湾的缺氧水中观察到高浓度的 H₂。表层海水中 H₂ 光的产生率和微生物消耗率分别为 1.80 至 17.78 nmol ^{L-1 h-1} 和 1.02-9.18 nmol ^{L-1 h-1}。当考虑整个混合层时，光产生约占总 H₂ 去除的 31%-43%，蓝藻可能是混合层中的另一个来源。与海-气交换相比，微生物消耗是海水中 H₂ 的主要去除途径。