氮(N)是生物生命活动的基本营养元素,N循环是整个生物圈物质和能量循环的重要组成部分。近几十年来,环境和资源问题的日益突出促进了人们对海洋生态系统的研究及对海洋资源的开发和利用,海洋中的N循环亦受到了广泛关注。尤其是20世纪90年代以来,随着国际地圈与生物圈计划(IGBP)、全球海洋通量联合研究(JGOFS)、 Nitrogen (N) is a basic nutrient of biological life activities. The N cycle is an important part of the entire biological cycle and energy cycle. In recent decades, the increasing prominence of environment and resources has promoted the research on marine ecosystem and the exploitation and utilization of marine resources. The N cycle in the ocean has also drawn extensive attention. Especially since the 1990s, with the International Geosphere and Biosphere Program (IGBP), the Joint Global Ocean Flux Research (JGOFS)