中文摘要：

为探讨巢湖磷形态内源污染特征及生物有效性,采用传统化学方法和梯度扩散膜技术（DGT）,分析了巢湖水体和沉积物磷形态的空间分布特征和不同区域沉积物对磷的吸附特性.结果表明,西部湖区水体中总磷（TP）和可溶性无机磷（DIP）浓度高于中、东部湖区,处于富营养化水平.不同湖区沉积物中TP、铁/ 铝结合态磷（Fe/ Al？P）和藻类可利用磷（AAP）由大到小依次为西部、东部和中部,钙结合态磷（Ca？P）分布没有明显差异,有机磷（OP）含量由大到小依次为东部、西部和中部湖区;沉积物中生物有效性磷（DGT-P）含量全湖分布差异较小,河口处波动较大,说明河口受河流携带污染物影响较大;沉积物中DGT？P 含量与高活性AAP、Fe/ Al-P、OP 和DIP 含量相关系数R 分别为0.541、0.547、0.731（P〈0.01）和0.438（P〈0.05）,因此可考虑将DGT 作为生物有效性磷监测手段.等温吸附实验表明东、西部湖区沉积物对磷酸盐具有较高吸附潜能,中部湖区较低;然而平衡溶液中DGT？P 却存在较大差异,西部湖区9 号样点最大平衡浓度（0.62 mg·L-1 ）约为东部湖区3 号样点（0.07 mg·L-1 ）的9 倍,说明沉积物对上覆水磷的生物有效性存在较大影响.

英文摘要：

To explore endogenous pollution and bio.availability of different forms of phosphorus （P） in the water and sedi.ments of Lake Chaohu, conventional chemical approaches and diffusive gradients in thin.films （DGT） technology wereused to analyze spatial distribution of different forms of P in the water and sediments and P adsorption by sediments in dif.ferent zones. Results show that the water in the western part of the lake was higher than the waters in the central and east.ern parts of the lake in content of total P （TP） and dissolved inorganic P （DIP） and could be sorted into the level of eu.trophication. Among the five chemically extractable forms of P in the sediments, TP, Fe/ Al.P （iron/ aluminum bound P）and AAP （algal.available P） in the three parts of the lake followed an order of western part 〉 eastern part 〉central part incontent; OP （organic P） in an order of eastern part 〉 western part 〉 central part; Ca.P （calcium bound P） did not varymuch between the parts; and DGT.P （P determined with the DGT method） did not either within the lake, but did in theareas of river mouths, indicating that the areas of river mouths were greatly influenced by the pollutants carried by riverflows. DGT.P in the sediments was positively related to highly active AAP, Fe/ Al.P,OP and DIP, with coefficient R being0.541, 0.547,0.731（P〈0.01） and 0. 438（P〈0.05）, respectively, which indicates that the DGT device was effective inmonitoring bio.available P in the sediments. Isothermal adsorption study indicates that the sediments in the western andeastern parts of the lake were both high in P adsorption potentiality, while those in the central part were quite low. Howev.er, DGT.P in equilibrium solutions varied sharply, with the highest equilibrium concentration of the sample from SamplingSite No. 9（0.62 mg·L-1） in the western part of the lake being 9 times as high as that of the sample from Sampling StieNo. 3（0.07 mg·L-1） in the eastern part of the lake, suggesting that s