摘要
对太湖不同营养水平和不同特征的4种沉积物的总磷、磷形态、粒径组成、化学组成进行了分析,模拟研究了不同pH值对上覆水体中总溶解性磷和溶解性活性磷含量的影响.结果表明,太湖沉积物样品总磷含量在336.1～3408.01mg/kg,属于中富营养化到极富营养化水平.pH值是影响磷释放的重要因素,碱性条件下,促进NaOH-P的释放;酸性条件下,促进HCl-P的释放.严重富营养化湖区沉积物的磷主要由无机磷组成,其中主要是NaOH-P,该区中pH值增加会导致磷释放量的大幅度增加,而pH值下降对磷释放量的影响较小.中富营养化湖区沉积物的无机磷组成中,部分湖区NaOH-P含量高,部分湖区HCl-P含量高,所以该区中pH值变化对沉积物磷释放的影响,由于NaOH-P和HCl-P含量不同而存在差异,NaOH-P含量较高,pH值增加会导致磷释放量的大幅度增加;HCl-P含量较高,pH值下降会导致磷释放量的大幅度增加.
Four kinds of sediments representing different nutrient levels and features of Taihu Lake, China were studied; total phosphorus form of the phosphorus, grain size and chemical composition of sediments were analyzed. Simulated study was made for the influence of different pH value on the contents of total dissoluble and soluble reactive phosphorus in overlaying water. The total P contents of these sediments samples were 336.l-3408.01 mg/kg, belonging to mestrophic to maximum eutrophic levels. The pH value was the important factor affecting the release of phosphorus from these sediments. Under acid and alkaline conditions it favored the phosphorus release; under alkaline condition it promoted the NaOH-P release; under acid condition, it promoted the HCl-P release. In Taihu lake heavy eutrophic area the phosphorus of sediment was composed mainly from inorganic phosphorus, in which it was mainly NaOH-P, so in Taihu lake heavy eutrophic area, pH value increasing could increase the amount of phosphorus release greatly, but pH value decreasing affected the amount of phosphorus release rather little. In the composition of inorganic phosphorus of the sediment in Taihu lake mestrophic area, NaOH-P and HCl-P contents in partial areas were high; thus, the influence of pH value change on the sediment phosphorus release in lake area of mestrophic level differed, due to different contents of NaOH-P and HCl-P in the composition of inorganic phosphorus. Higher content of HCl-P with pH value decreasing could induce great increase of phosphorus release.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2004年第6期707-711,共5页
China Environmental Science
基金
国家重点基础研究发展规划项目(2002CB412304)
关键词
太湖
沉积物
磷形态
磷释放
营养水平
PH值
Taihu Lake
sediment
phosphate forms
phosphate release
nutrient level
pH value
