中文摘要：

分析了泉州湾溶解无机氮（DIN）春季的含量分布、组成、潮周期及其与环境因子的关系.根据高值区判断洛阳江口以县区农田养殖输入硝酸氮（NO3--N）为主,而晋江口以市区生活污水输入氨氮（NH4＋-N）为主,DIN含量的平面分布受NO3--N与NH4＋-N共同控制.DIN的平均组成为NO3--N最高,NH4＋-N其次,NO2--N远低于二者,NH4＋-N平均占比达35%左右,DIN的组成未达到热力学平衡.根据DIN含量与溶解氧（DO）及化学需氧量（COD）的相关性分析,推测三氮转换不仅受到氧化还原过程的影响,还受更为复杂的来源、人类活动及生物过程等的影响;根据DIN含量与盐度的关系,NO3--N及NO2--N均呈现保守行为,NH4＋-N淡水端有一定的增加现象,DIN含量与盐度的关系受NO3--N和NH4＋-N共同控制;DIN含量还受到悬浮物含量、温度、盐度及p H值等环境因子的控制,结合DIN含量与叶绿素a的相关性及分布情况,可推测春季DIN主要来源不是浮游植物分解.不同站位DIN含量的潮期变化相似,基本上都表现为涨潮冲淡作用下含量降低而落潮后回升.除此之外,泉州湾DIN含量的年际增长及超标均比较严重,需要采取相应的治理措施.

英文摘要：

In this paper we study the relations of distribution and composition of dissolved inorganic（ DIN） with tidal change and other factors in spring of Quanzhou Bay. The result shows that Luoyang River inputted more NO3--N from cropland aquaculture while Jinjiang River inputted more NH4＋-N from municipal sewage to the bay according to the nutrient content. The horizontal distribution of DIN was controlled both by NO3--N and NH4＋-N. The average percentage of NH4＋-N reached 35%,so the composition of DIN didn’t balanced by the thermodynamic equilibrium in Quanzhou Bay. The relationships among different nitrogen species were affected by complicated nitrogen sources,human activities and biochemical processes according to the correlations between DIN and DO,COD. According to the linear regressions between DIN and salinity,the mixing behavior of NO3--N and NO2--N is suggested to be con-servative besides some NH4＋-N from the fresh water end. Also,the mixing behaviors of DIN were controlled by both NO3--N and NH4＋-N. DIN was also controlled by environmental factors such as suspended solids,temperature,salinity,p H and chla. According to the distribution of DIN and its correlations with chl a,we suggest that the main source of NO3--N is from human input. Tidal cycle variation of DIN at different stations were similar,both showed a decreasing trend during the tide rising due to the seawater dilution and an increasing trend during the tide falling.Moreover,the excess and annual increment of DIN concentrations was much serious in Quanzhou Bay where more attentions should be paid.