碳中和是应对全球气候变化的重要手段，而负排放技术是实现碳中和目标的关键一环。 海洋作为地球上最大的活跃碳库，在负排放技术开发中有着巨大潜力，为实现碳中和目标提供了 重要支撑。其中，海水碱度提升技术被认为是一种高效且兼具生态效益的负排放技术，即通过人 为投加碱性物质提高表层海水碱度，在促进海洋吸收CO2的同时，缓解海洋酸化。基于海洋碳酸盐 平衡体系等理论基础，概述了海水碱度提升技术的基本原理，并结合国内外研究进展，总结了不同 尺度的研究。从多维度对比评估了该技术的碳汇潜力和成本，指出其在实施路径、生态影响评估 和公众接受度等方面的挑战。结合海水碱度提升技术特点和我国沿海地区实际情况，提出了耦合 污水处理厂基础设施和海岸带工程等的协同实施路径，为推动海水碱度提升技术的工程应用提供 创新思路，进一步丰富了发展海洋蓝色碳汇的科学内涵和路径

Abstract：Carbon neutrality is a crucial strategy for combating global warming, and Negative Emissions Technologies (NETs) are key to achieving this goal. The ocean, as the largest carbon reservoir on Earth, plays an irreplaceable role in regulating the global carbon cycling and holds significant potential for negative emissions. Ocean alkalinity enhancement is regarded as a highly efficient and ecologically beneficial negative emissions technology. This technology not only increases ocean alkalinity by adding alkaline minerals to seawater, thereby enhancing the absorption of atmospheric CO2, but also improves the buffer capacity to resist the ocean acidification. This study introduces the mechanisms and advancements in ocean alkalinity enhancement research at multiple scales, based on the dissolution theory of carbonates in the ocean. Assessing the potential for negative emissions and associated costs reveals several challenges regarding implementation pathways, environmental impacts and public acceptance. Considering the specific conditions of China's coastal regions and the characteristics of ocean alkalinity enhancement technology, the study proposes the pathway integrated with wastewater treatment plant and coastal engineering. Furthermore, it presents an innovative concept on the application of ocean alkalinity enhancement and enriches the scientific understanding of blue carbon sinks.