【摘要】 磷是淡水水体富营养化关键性限制因子之一.本研究采用化学连续提取法,分析贵州草海岩溶湿地不同水位下沉积物总磷（TP）与不同形态磷含量及分布特征,试图揭示水位抬升对草海沉积物磷释放风险的影响.结果表明:草海沉积物总磷（TP）含量在206.30—577.30 mg·kg^-1之间,均值为378.60 mg·kg^-1,在水位梯度下呈两端高中间低分布特征;磷形态组成以有机磷（Or-p）为主,自生钙磷（ACa-p）、碎屑钙磷（De-p）和闭蓄态磷（Oc-p）次之,交换态磷（Ex-p）、铝磷（Al-p）和铁磷（Fe-p）为最低,即草海沉积物磷活性以潜在释放和非活性为主,活性部分比重较低;活性磷（Act-p）含量在不同水位梯度下分布变化不大,潜在释放磷（Or-p）含量沿着水深加大呈逐渐增加趋势,非活性磷（Ina-p）含量稳定并与水位无明显相关性;可见,草海水位抬升将不会显著增加沉积物磷的直接释放风险,但会积累一定水平的潜在磷释放风险.更多还原

【Abstract】 Phosphorus is one of key factors leading eutrophication of fresh water bodies. In this study, the chemical continuous extraction procedure was used to analyze the content and distribution of total phosphorus（TP） and different forms of phosphorus in sediments of Caohai, a karst wetland in Guizhou Province. It was trying to reveal the impact of water level uplift on the risk of phosphorus release from the sediments of Caohai wetland. The results showed that the content of TP in sediments of Caohai wetland ranged from 206.30 to 577.30 mg·kg^-1, with an average value of 378.60 mg·kg^-1. Under the water level gradient, the distribution of TP concentration is in the shape of "U" with high concetrations at both ends and low concentrations in middle. The composition of phosphorus forms is dominated by organic phosphorus（Or-p）, followed by autogenous calcium phosphate（ACa-p）, detrital calcium phosphate（De-p） and closed storage phosphorus（Oc-p）, and the least part is exchangeable phosphorus（Ex-p）, aluminum-bound phosphorus（Al-p） and iron-bound phosphorus（Fe-p）. Therefore, phosphorus in the sediments of Caohai wetland mainly existed as potential release and inactivity forms, while the active part presented little effect to the cover water. The gradient distribution of Act-p was relatively uniform, and the Or-p increased gradually along with the variation of water depth. The Ina-p content was stable and had no significant correlation with water level.Therefore, there would be no significant increase in the direct release risk of phosphorus with the water level uplift. However, there might be an accumulation of potential release risk.更多还原