摘要
选取衡水湖14个具有代表性点位的沉积物样品,分析沉积物中总有机碳(TOC)、总磷(TP)、速效磷、pH 以及不同形态氮、磷的分布特征.结果表明:衡水湖沉积物中 TOC 的平均含量为20.29 g/kg,pH平均值为 7.77,呈弱碱性.不同形态氮的平均含量为SAEF-N(0.06±0.02 mg/g)＜IEF-N(0.15±0.03 mg/g)＜SOEF-N(0.22±0.09 mg/g)＜WAEF-N(0.73±0.21 mg/g),SOEF-N中NO3--N占主导地位,其他三种形态氮中NH4+-N占主导地位.TP的平均含量为1.36 g/kg,属于中等以上污染水平,速效磷的平均含量为15.96 mg/kg,不同形态磷的平均含量为Ca-P(129.40 mg/kg)＜O-P(117.61 mg/kg)＜NH4Cl-P(56.10 mg/g)＜Fe-P 和 Al-P(35.74 mg/kg),衡水湖沉积物中磷释放的风险相对较低,氮存在一定释放的风险.
Abstract
Sediment samples from 14 representative sites in Hengshui Lake as the research object to analyze the change characteristics of total organic carbon(TOC),total phosphorus(TP),available phosphorus,pH,and different forms of nitrogen and phosphorus in the sediments.The results showed that the average TOC content and pH value in Hengshui Lake sediments were 20.29±0.62 g/kg and 7.77±0.14 respectively,showing a weak alkalinity.The average nitrogen content of different forms was as follows:strong base extractable nitrogen(SAEF-N,0.06 mg/g,46.54%)<ion exchange nitrogen(IEF-N,0.15 mg/g,17.59%)<strong oxidizer extractable nitrogen(SOEF-N,0.22 mg/g,38.86%)<weak acid extractable nitrogen(WAEF-N,0.73 mg/g,28.82%).NO3--N was dominated in SOEF-N,and NH4+-N was dominated in the other three forms of nitrogen.The average content of TP was 1.36 g/kg,which belonged to the above medium pollution level,and the average content of available phosphorus was 15.96 mg/kg.The average content of phosphorus in different forms was calcium bound phosphorus(Ca-P,129.40 mg/kg)<closed storage phosphorus(O-P,117.61 mg/kg)<weakly adsorbent phosphorus(NH4Cl-P,56.10 mg/g)<the sum of Fe-bound phosphorus(Fe-P)and Al-bound phosphorus(Al-P)(35.74 mg/kg).In summary,the risk of phosphorus release in Hengshui Lake sediments was relatively low,and there was a certain risk of nitrogen release.
NETL
NSTL
万方数据