孝感市野猪湖沉积物及水生植物残体中的氮、磷分布特征

Spatial Distribution of Nitrogen and Phosphorus in the Sediments and Aquatic Plant Residues from Yezhu Lake, Xiaogan City

对孝感市野猪湖6个采样点30 cm沉积物柱样中沉积物及水生植物残体中总氮(TN)和总磷(TP)进行了研究。结果表明,两者TN的含量均以Ⅰ号点最高,说明氮可能主要来自于河流的汇入。沉积物的TN和TP在垂向分布上,与沉积深度相关不显著。水生植物残体的TN与沉积深度相关不显著;但TP在垂向分布上,6个点的0~5 cm段的TP平均含量都高于25~30 cm段,TP与沉积深度呈显著负相关,即沉积年代越晚,TP含量越高,沉积年代越早,TP含量越低。研究认为,湖泊沉积物中的水生植物残体可作为湖泊营养化过程中的一种证据材料,对研究浅水湖泊的营养变化过程具有参考意义。

Sedimentary columns were collected and sliced by 30 cm vertically from 6 sampling points in Yezhu Lake to study on the distribution characteristics of total nitrogen and total phosphorus in the sediments and aquatic plant residues.The results showed that the highest content of total nitrogen(TN)was detected in both sediments and aquatic plant residues from sampling siteⅠ,indicating that nitrogen were mainly from the lake's feeder rivers.In the vertical distribution,the contents of TN and TP in sediments had no significant correlation with sediment depth.In addition,there was no significant correlation between the content of TN in aquatic plant residues and sediment depth.However,the average content of TP in 0~5 cm columns collected from 6 sampling points was much higher than in 25~30 cm columns,suggesting that the content of TP in aquatic plant residues was significantly negative correlated with sediment depth.In other words,the more modern the age of the sedimentation,the higher the content of TP was,and vice versa.Therefore,the aquatic plant residues in lake sediments can provide evidence for the lake eutrophication,which is valuable for studying changes in nutrition in shallow lakes.