海洋浮游植物对磷的响应研究进展

磷是海洋浮游植物赖以生存的一种必需营养元素.海洋浮游植物对磷的响应,与初级生产力、碳循环以及固氮作用密切相关.总结了浮游植物可利用的磷源:优先吸收溶解无机磷；在寡磷海域,可通过相关酶类协助利用溶解有机磷来抵御无机磷的缺乏.对比了不同种类浮游植物对不同形态磷源利用方式的差异并从浮游植物生理学角度阐述了存在差异的根本原因.探讨了浮游植物对低磷环境的响应机制.近期的研究发现浮游植物细胞表面可以吸附磷,该发现有利于更加准确地衡量浮游植物承受的营养盐限制问题,进一步完善对海洋磷储库及其生物地球化学循环的认识.最后提出了今后需进一步研究的关键科学问题:浮游植物细胞表面吸附磷的机制；对不同结构有机磷化物的利用机理；浮游植物对磷的海洋生物地球化学循环的响应及反馈作用.

Advances in Studies of Phosphorus Utilization by Marine Phytoplankton

Phosphorus is a necessary nutrient utilized by marine phytoplankton. Responses of marine phytoplankton to phosphorus are closely linked with primary production, carbon cycle and nitrogen fixation. The phosphorus pools utilized by phytoplankton are summarized. Phytoplankton prefers dissolved inorganic phosphorus, and can also utilize Dissolved Organic Phosphorus (DOP) by some enzymes in phosphorus deficient regions. Utilization of various phosphorus forms by different phytoplankton species is then compared. Phytoplankton physiology studies explained differences in phosphorus availability to different phytoplankton species. Strategies of phytoplankton response to phosphorus deficiency are also summarized. Recent studies indicated phosphorus could be adsorbed onto phytoplankton cell surface. Distinguishing cell surface adsorbed phosphorus can help to assess the nutrient limitation on phytoplankton growth more accurately and to better understand phosphorus inventory and its marine biogeochemical cycle. Finally, challenges in further studies are suggested as follows: the mechanism on phytoplankton cell surface adsorbed phosphorus; the mechanism on utilization of different DOP pools by phytoplankton; the feedback and response of phytoplankton to phosphorus marine biogeochemical cycle.