中文摘要：

以茅洲河口为研究对象，通过2014年1月对茅洲河153个站位进行的全潮观测，并测定其各站的无机营养盐质量浓度水平，分析了各站位营养盐的时空变化及成因，并估算了营养盐的人海通量。结果表明：茅洲河口NH4^＋-N、DTN、P04^3-P、SiO3^2- -Si等营养盐污染较严重，A1、A2、A3站位的NH4^＋-N、DTN、Po4^3- -P、siO3^2- -Si质量浓度范围相应地分别为15．8-19．8、18．0-29．0、0．25～2．15、6．16-9．03mg／L；11．5～23．4、25．9-53．6、1．70-2．70、5．04～6．28mg／L；0．74～7．39、3．06～24．9、0．01～0．98、2．77～4．17mg／L。A2站位的NH4^＋-N、DTN与潮汐的变化一致，表现出涨潮时升高、落潮时降低的变化特征；而各形态的磷、硅营养盐与潮汐的变化则不明显。在形态分布上，氨氮是溶解态总氮的主要存在形态，溶解态总磷则以磷酸盐为主。除硝态氮外，其余各营养盐之间均存在显著相关性，说明流域内氮、磷等营养盐的来源大致相同，而高质量浓度的氨氮表明生活污水等点源污染是流域内营养盐的重要影响因素。N／P比值表明茅洲河口水域磷是浮游植物的限制性因子。通量计算表明，茅洲河口AI、A2站位的NH4^＋-N的人海通量均较大，分别高达48．0和71．8g／s。

英文摘要：

In order to investigate the spatial and seasonal variation of nutrients and associated flux within a tidal cycle in the Maozhou Estuary, thirty-six water samples were collected from 3 sites （A1, A2 and A3） every two hours in January 2014 and analyzed for NH4^＋-N, NO3-N, DTN, PO4^3-P, DTP, and SiO3^2-Si. The results showed that the concentrations of NH4^＋-N, DTN, pO4^3-P, SiO3^2- -Si were 15.8-19.8, 18.0-29.0, 0.25-2.15 and 6.16-9.03 mg/L at A1, 11.5-23.4, 25.9~53.6, 1.70-2.70 and 5.04-6.28 mg/L at A2, and 0.74-7.39, 3.06-24.9, 0.01-0.98 and 2.77-4.17 mg/L at A3, respectively. The changes of NH4-N, DTN were consistent with that of tide at A2 except PO4^3- -P, DTP and SiO3^2- -Si. NH4^＋-N and PO43^- -P were found to be the major components of nitrogen and phosphorus. All nutrients except nitrate were correlated at a significant level of 0.01 with each other, indicating a common source of nutrients. Sewage discharge to the Maozhou River contributed principally to the high concentration of NH4^＋-N in the estuary. According to the results of nutrient ratios, it was considered that phosphate was a limiting factor for phytoplankton growth in the Maozhou Estuary. The fluxes of nutrients were calculated, yielding a high flux of NH4-N of 48.0 and 71.8 g/s at A1 and A2 respectively.