武汉市菱角湖沉积物中营养元素的分布特征

The Dstribution of Nitrogen and Posphorus in the Sediment of Lingjiaohu Lake in Wuhan

研究了武汉菱角湖沉积物中N、P元素的水平和垂向分布特征,采集并分析了3个深达0.5~1.0 m的沉积柱.结果表明:全湖沉积物中平均P含量为(0.76±0.23)^(1.32±0.35)g/kg.湖心点沉积物总氮含量最高,高达(10.96±0.83)g/kg,沿岸两个点总磷含量分别为(8.34±0.12)g/kg和(9.26±1.21)g/kg.在垂向呈阶段性变化,N、P呈现阶段性变化,垂向分布上40 cm以内的中表层沉积物的营养元素含量高于稳定层,但表层含量(0~20cm)反而低于中层(20~40 cm).说明对营养元素的外源控制达到了一定效果,沉积物中氮磷元素均有所降低,但沉积物中的高含量的N、P元素仍是湖泊的主要来源.

To investigate the spatial distribution of nitrogen （ N） and phosphorus （ P） in the sediments of Lingjiaohu Lake , three sedimentary columns up to 0.5~1.0m were acquired and analyzed .The results indicated that the average P contents was （0.76 ±0.23）^（1.32 ±0.35） g/kg.The total N content in the sediments of the middle of the lake was the highest , up to （10.96 ±0.83） g/kg;while in two of the offshore sampling points , it was（8.34 ±0.12）g/kg and（9.26 ±1.21）g/kg respectively.The distribution of nutritive elements also varies vertically , the N, P content in the 0-40 cm surface layer was higher than that in the deeper section .However, the N,P content in the 0~20 cm surface region was lower than that in 20-40 cm the middle layer , suggesting that the measures for the control of nutritive elements in recent years have achieved some effect.The N, P content in the sediments have reduced , but are still in a high level and remain the major endogenous load of the lake .