烟台四十里湾养殖水域氮的存在形态研究

FORMS OF NITROGEN IN THE YANTAI SISHILI BAY CULTIVATED WATER

１９９７年５、８、１１月及１９９８年３月对烟台四十里湾养殖水域的溶解无机氮、溶解有机氮及颗粒氮进行了调查，对不同形态氮的分布、季节变化及在总氮中所占比例进行了分析。结 果表明，春、夏季溶解态氮的分布主要受自然及养殖生物活动控制；秋、冬季主要受陆源输入 及物理混合控制。颗粒氮的分布主要受生物活动及陆源输入共同控制。全年总氮主要以溶解态氮为主，其中有机氮为主要存在形式，溶解无机氮主要以氨氮为主。溶解态氮的含量及在总氮中的比例从春季到冬季升高；颗粒氮正相反，颗粒氮的变化趋势与叶绿素ａ的变化基本相一致。

Four seasonal investigations into different nitrogen forms were carried out from May 1997 to March 1998 in the Yantai Sishili Bay cultivated water. The forms of nitrogen were separated into dissolved and particulate forms by filtration. The dissolved form was mainly composed of inorgenic and organic species. The dissolved inorganic nitrogen included ammonium, nitrate and nitrite. The results showed that the range of dissolved total hitrogen concentration was 7.16 117.07μmol/L, representing 69%-97% of total nitrogen. The range of dissolved inorganic nitrogen concentration was 0.73-32.12μmol /L. 43%-81% of dissolved inorganic nitrogen was ammonium, 13%-43% nitrate and 3%-29% nitrite. The range of dissolved organic nitrogen concentration was 6.04-97.12μmol/L, reptesenting 65%-97% of dissolved total nitrogen. The range of particulate nitrogen concentration was 0-13.71μmol/L representing 3%-31% of total nitrogen. The distributions of dissolved nitrogen in the Yantai Sishili Bay were influenced by natural and cultivated biological activities in spring and summer and by continental input and physical mixing in autumn and winter. The distributions of particulate nitrogen were controlled by both biological activities and continental input. The major form of total nitrogen through the whole year was dissolved nitrogen in which organic nitrogen was the main species. Ammonium was the dominant species of dissolved inorganic nitrogen. The dissolved nitrogen concentration and the percentage in total nitrogen became higher from spring to winter whose bend was contrary to chlorophyll-a; however, particulate nitrogen changed with a trend which was consistent with that of the chlorophyll-a.