摘要:
The vertical distribution and influencing factors were examined in combination with TN,TP,OM and particle size which was from the middle part of Dali Nor's columnar sediment.The TP,TN and OM in sediments range from 2.12 g·kg-1to 3.71 g·kg-1,0.48 g·kg-1to 0.74 g · kg-1and 4.71 g·kg-1to 7.97 g· kg-1 with an average of 2.98 g · kg-1,0.64 g· kg-1 and 6.29 g· kg-1 respectively.During 1832 -1941,the TP,TN and OM with a lower content and kept a nearly even trend.During 1941-1965,the TN and TP concentration presented a trend of first increasing then decreasing,OM content showed a trend of decrease.During 1965-2011,the concentration of TN,TP and OM presented a trend of increasing in total.The C/N ratio in sediment explain the zooplankton and phytoplankton are the main source of the nutrients and organic matter.Primary composition of grain size of sediment is clay.The OM,TN and TP in sediment shows a significant correlation.It means the organic nitrogen was the mainly nitrogen forms in sediment.The biogeochemical cycles of phosphorus and the sediment organic matter has a greatly correlation.The deposition behavior between the sediment phosphorus and nitrogen are similar since the TN and TP has positive correlation.TN,TP and OM in sediment presented on positive correlation with grain which the diameter is less than 4 μm,but revealed the negative correlation with grains which have other diameters.%通过对达里湖湖中心柱状沉积岩芯总氮(TN)、总磷(TP)、有机质(0M)和粒度指标的测试与分析,探讨其垂向分布特征及影响因素.结果表明,营养盐TN、TP和OM的含量分别为2.12~3.71 g/kg、0.48 ~0.74 g/kg和4.71% ~7.97%,平均值分别为2.98 g/kg、0.64 g/kg和6.29%.1832~ 1941年,TN、TP和OM含量较为稳定且含量较低;1941 ~ 1965年,TN和rP含量不同程度上先增加后减小,OM含量呈减小趋势;1965~2011年,TN、TP和OM含量整体上表现为增加趋势.沉积物中C/N值显示有机质及营养盐的主要来源为浮游动植物,沉积物粒级组成以粘土为主.沉积物中OM与TN和TP极显著相关,说明沉积物中氮主要以有机氮的形式存在,有机质与磷的生物地球化学循环也有相当紧密的关联;TN与TP表现出极显著相关性,说明沉积物氮、磷在沉积行为上有一定的相似性.沉积物中TN、TP和有机质与粒径小于4μm的颗粒正相关,与其它粒径的颗粒负相关.