巢湖沉积物中氮与磷赋存形态研究

Forms of Phosphorus and Nitrogen Existing in Sediments in Chaohu Lake.

利用连续提取法研究巢湖沉积物中不同赋存形态P、N的组成和分布特征。结果显示,巢湖沉积物中总P含量为0.1110.655 g.kg-1,平均0.358 g.kg-1,主要由无机P组成(65%72%),赋存形态以铁结合态为主;巢湖沉积物中总N含量为0.2200.922 g.kg-1,平均0.532 g.kg-1,以有机N为主,约占总N的94.7%。有机N含量与有机指数等指标显示,巢湖处于清洁与尚清洁状态。湖泊沉积物中有机质、总N、总P间相关分析表明,湖泊营养物质来源具同一性趋势;有机C/N比值的研究结果显示,有机质主要来源于陆源。

In order to investigate cycling and burial of phosphorus and nitrogen in Chaohu Lake, the sequential extraction method was used to measure different forms of phosphorus and nitrogen in sediments of the lake. It was found that total P in the sediment ranged from 0.111-43. 655 g·kg^- 1, averaging 0.358 g·kg^- 1, and was composed mainly of inorganic P （65%-72%）, dominated with Fe-bound P. Total N in the sediment ranged from 0. 220-0. 922 g·kg^- 1, averaging 0.532 g·kg^- 1, and was composed mainly of organic nitrogen （94.7%）. All these indices signify that Chaohu Lake is in the state of cleanness and almost cleanness. The very close linear relations between organic matter, total phosphorus and total nitrogen in the sediments indicate the nutrients in Chaohu Lake come from the same source. The mean TOC/N ratio of the sediment suggests that the organic matter in Chaohu Lake originates from land.