中文摘要：

海水中低浓度的亚硝酸盐和硝酸盐的测定方法主要有4种，即分光光度法（富集分光光度法和液芯波导分光光度法）、高效液相色谱法、荧光法和化学发光法。这些测定方法比传统的分光光度测定法有更高的灵敏度和更低的检测限，可以对海水中纳摩尔级低浓度的亚硝酸盐和硝酸盐进行测定。化学发光法和液芯波导分光光度法的自动化程度高，测定时对样品的需求量少，后者还实现了多个参数的实时现场测定，因而成为目前海水中低浓度亚硝酸盐和硝酸盐测定的主流方法，具有广阔的应用前景。

英文摘要：

The concentrations of nitrite and nitrate in the open ocean of South China Sea and in the area of harmful marine microalgae bloom along the coast of mainland China （especially Changjiang estuary and East China Sea） are constantly lower than the detection limit of the conventional spectrophotometric method. This paper presents other authors＇ methods, by which the nano-molar level concentrations of nitrite and nitrate in seawater may be detected. The methods include preconcentration-spectrophotometric method, liquid core waveguide-spectrophotometric method, high performance liquid chromatographic method, fluorimetric method and chemiluminescent method. We made a synopsis of their principles, procedures, and applications of these methods, and compared them on detection limits, precisions, advantages, and disadvantages.