扎龙湿地表层沉积物中磷形态的分布特征

表层沉积物中磷形态的浓度是衡量湿地富营养化程度的最基本指标，为了对研究区表层沉积物中总磷及磷形态的空间分布特征进行分析，通过SMT法对扎龙湿地表层沉积物中280个采样点的磷含量进行测量，在GIS的支持下，利用Kriging插值方法了解其空间差异并探究原因。结果表明，研究区表层沉积物中总磷（TP）含量在202~1014 mg/kg之间，主要以无机磷（IP）形态存在，平均占TP的56%。TP主要集中在研究区的中部地区，并呈现出由西南向东北递减的趋势，且南部和北部地区含量较低；各形态磷的分布特征均与TP相似；有机磷（OP）的分布特征主导了TP的分布；各形态磷之间均呈现显著相关，揭示出扎龙湿地表层沉积物中各形态磷间可能相互转化；研究区内源负荷严重，对扎龙湿地富营养化具有较大潜在威胁。

Distribution Characteristic of Phosphorus Forms in Surface Sediments in the Zhalong Wetland

In order to investigate the spatial variability of TP and different forms of phosphorus in surface sediment from 280 samples in the Zhalong wetland, the geostatisties method combined with geographic information system （GIS） were applied. TP and different forms of phosphorus were determined by SMT method and the concentrations of TP ranged from 202 to 1014 mg/kg. The results indicated that TP was dominated by inorganic phosphorus （IP）, which accounting for 56%. The contents of TP and different forms of phosphorus were high in the middle of the study area, and which were relatively low in the north and south. The distribution characteristics of TP were mainly decided by the distribution characteristics of OP. Each of the phosphorus forms was likely to transform to another, and the serious of inner source pollution potentially augmented the eutrophication in Zhalong wetland.