长江口附近氮的地球化学 Ⅱ.长江口附近海水中的亚硝酸盐及氨  

MARINE GEOCHEMISTRY OF NITROGEN NEAR ESTUARY OF CHANGJIANG RIVER Ⅱ .NITRITE AND AMMONIA IN SEA WATER NEAR ESTUARY

作　　者：顾宏堪[1] 马锡年[1] 沈万仁[1] 任广法[1] 陈志[1] 习焕祥 李国基[1] 张莲影[1] 

机构地区：[1]中国科学院海洋研究所

出　　处：《山东海洋学院学报》1982年第2期31-38,共8页

摘　　要：海水中的NO2-N，是NH4氧化成为NO3ˉ的中间形态，是氧化还原态的指标。而NH4-N则是有机N分解的第一个无机产物。NO2ˉ及NH1+如同NO3ˉ样，可直接被浮游植物同化。大陆迳流及大气降水常带来大量的NH4+。当浮游植物茂盛时，浮游植物与NH4^+构成了直接循环，The horizontal distribution of NO2-N near estuary of the Changjiang River during five cruises between August and December 1963 shows that there is a gradient in summer-autumn with a tendency of high contents in estuary and low in offshore water, such as 10→0.8 mg/m3 in August. In autumn-winter, it tends to homogeneous distribution. Obviously, the high concentration is from the river water. The NH4-N contents are high in the estuarine water in all seasons, 60-140→20 mg/m3. The NO; maximum layer is a characteristic of vertical profile distribution of NO2-N. The mechanism of NO2- maximum is due to consumption of NO2- by phytoplankton in upper water layer and regeneration of NO; from dead organisms below the thermocline. It coincides with the high phytoplankton mass, high O2% high total organic-N and low-nutrients in the water layer above the thermocline. The NH4-N contents in the upper layer and especially in bottom are higher than in the middle layer. In monthly variation, high NO2-N is in summer-autumn in estuarine and coastal waters and NO2- maximum layer, and in autumn-winter in other offshore area.However, the content of total inorganic nitrogen near the estuary of the Changjiang River is high which keeps high primary productivity, and it is not a limiting factor of phytoplankton.In the nitrogen cycle in the sea, the different thermodynamic free energy ΔG0 in NH4+=NO2-and NO2- = NO3-, which shows the spontaneous degree of reaction, coincides with the reaction rate of kinetics dc/dt, it shows that there may be Various catalysts, especially enzymes, in sea water owing to the activity of organisms, so there may be a relationship between ΔG0 and dc/dt in the sea. After catalyst removes the potential barrier of kinetics of a spontaneous reaction, the reaction will take place automatically and directly from initial state to final state, and the reaction rate of kinetics, dc/dt, may relate to the thermodynamic free energy, ΔG0, which shows the spontaneous degree of reaction.

关 键 词：长江口 氮 海水化学 亚硝酸盐 氨 

分 类 号：P734.44[天文地球—海洋化学]