滇池沉积物总氮的时空变化特征研究

Spatial and Temporal Dynamic Variation of Nitrogen in Sediment of Dianchi Lake

采用GPS定位,对滇池海埂、斗南、罗家村、新街、昆阳等5个代表性样点沉积物总N含量进行为期1年的动态监测,分析了不同区域、不同层次、不同时期滇池沉积物总N的变化.结果表明全湖全年沉积物总N的平均含量为4.91g/kg,年变化范围是4.13～5.41 g/kg,呈现明显的季节性变化,总体趋势夏季高、冬季低,但不同区域变化高峰和趋势不同.沉积物总N层次变化差异显著,表现为表层＞中层＞底层,各层次年变化范围分别为表层3.54～9.10g/kg、中层2.72～8.04 g/kg、底层1.23～5.37g/kg.各区域沉积物总N平均含量以海埂和罗家村最高,斗南和新街较低.

The spatial and dynamic variation of total nitrogen contents at different depths of sediments in 5 representative sites of Dianchi Lake (Haigeng, Dounan, Luojiacun, Xinjie, and Kunyang) were studied from May 2003 to May 2004. The results showed that: The average content of sediment total nitrogen was 4.91 g/kg with an annual range of 4.13 ~ 5.41g/kg. Sediment total nitrogen was influenced obviously by seasons, i.e., high in summer and low in winter. The peak and trend of sediment nitrogen content in different sites and at different layers were significantly different, which showed an order of surface > middle > bottom, varied at 3.54 ~ 9.10 g/kg, 2.72 ~ 8.04 g/kg, 1.23 ~ 5.37 g/kg, respectively. The nitrogen contents were higher in Luojiacun and Haigeng, while lower in Dounan and Xinjie.