海洋施肥系采取人工措施向海洋上层提供氮、磷、铁等限制性营养元素以增加海洋初级生产力的行为，其在增殖生物资源和减缓气候变化方面均具潜力。海洋施肥研究已有20年历史，但国内尚无此类研究。本文介绍了海洋微量元素铁和大营养元素氮、磷施肥的概念和基本原理，回顾海洋施肥研究发展历程，总结现有研究成果，并简要评述海洋施肥技术在应用方面存在的争议。在此基础上，着重探讨海洋施肥在南海外海渔业开发方面的应用前景。南海光热充足，但外海表层水体大营养元素匮乏，生物生产力低下，大营养元素施肥可提高海域初级生产力，从而可持续地增加渔业产量；施肥促进浮游植物繁殖而在特定海域形成的饵料生物密集区会吸引鱼群聚集，从而提高外海渔业捕捞效率。南海北部近海渔业资源已过度利用，在继续控制捕捞渔船数量和功率的情况下，开发外海施肥的渔业资源增殖技术有助于部分转移近海捕捞压力，为近海渔业的恢复性增长创造条件。%Ocean fertilization is the intentional introduction of nutrient elements to certain region of the upper ocean to enhance primary productivity. It has potential to increase sustainable fish catch and sequester carbon di-oxide from the atmosphere. The study of ocean fertilization has lasted for 20 years, and the concept has extended from iron fertilization for mitigating climate change to macronutrient nourishment for storing carbon while at the same time increasing marine protein production. However, no such study has ever been undertaken in China and understanding of the concept is incomplete. An effort was made in this paper to introduce the concepts and princi-ples of micronutrient iron fertilization and macronutrient nitrogen and phosphorus nourishment. The history and recent progress in the study of ocean fertilization, as well as disputes over its application were also reviewed. Examination of the debate over a low fraction of new primary production sinking as particulate organic carbon leads to the suggestion that the most flows through the food web and ocean fertilization may have a greater poten-tial for increasing sustainable fish catch. The potential of macronutrient nourishment for fishery development in the oligotrophic South China Sea was further explored. In the central South China Sea basin, there is abundant heat and sunlight in the euphotic zone, but the phytoplankton primary productivity is very low. The biological productivity is strongly limited by available macronutrients because of permanent stratification. It was suggested that intentional introduction of macronutrient elements could help to increase new primary production and hence sustainable fish catch. The enriched patch with a bloom of dietary plankton may serve to attract and concentrate fish schools. This would increase fishing efficiency for the dispersing oceanic species. Fish stocks in the coastal and shelf waters of the northern South China Sea are in a status of depletion and overfishing, respectively. Ocean fertilization in the oligotrophic South China Sea represents a potential opportunity to relieve heavy fishing pres-sure on the coastal and shelf stocks. Assuming continuation of the current policy of strict limits on the number of fishing licenses and total fishing horsepower, developing a fishery in the open sea with ocean fertilization would lead to partial relocation of fishing effort away from the heavily fished waters. In addition to the enhanced fish production in the open sea, this would correspond to a reduction in fishing pressure and a recovery growth in fish harvest in the coastal and shelf waters.
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