水生植物种植场磷素分布特征与植物吸收

研究了水生植物种植场水体、沉积物及植物的磷含量及分布特征,结果表明进水的P浓度高于V类水标准,水生植物种植区内的由于受到沉淀、吸附及植物吸收的影响,水体P浓度远低于进水,水体不同形态P与TP之间呈现良好的相关关系;沉积物的TP质量分数在335～672 mg.kg-1之间,表层沉积物P质量分数是影响底层沉积物P质量分数的主要因素之一,沉积物中的TP和IP、OP之间同样存在相关性;水生植物对P均具有较好的吸收富集能力,不同水生植物的迁移系数均在0.5以上,平均为0.82,其中的黄花蔺（Limnocharis flava）与欧慈菇（Sagittaria sagittifolia）显示对P的良好吸收和迁移能力。基于本次调查的水生植物P质量分数统计分析表明,95%的水生植物地上部P质量分数正常值范围在1 415～4 947mg.kg-1之间,而地下部的P质量分数正常值范围在2 178～5 702 mg.kg-1之间。

Phosphorus distribution characteristics and its phyto-extraction in a hydrophytes breeding nursery

Phosphorus concentration and distribution characteristics of water,sediments and plants in a hydrophytes breeding nursery were studied in this paper.The result indicated that inflow P concentrations were much higher than the Class V surface water stan-dard.It was also observed that P concentrations were much lower in the hydrophytes breeding area than those in the inflows which might attribute to the effects of precipitation,adsorption and phytoextraction.There was a significant relationship between Total Phosphorus（TP） and different P fractions.Total phosphorus concentration of surface sediments ranged from 335 mg·kg-1 to 672 mg·kg-1 and had an obvious effect on TP concentration of lower-level sediments.Inorganic P and Organic P of sediments had a posi-tive correlation with TP of sediments.Data showed that all tested hydrophytes samples exhibited high ability for P accumulation and the transfer coefficients were larger than 0.5,with a mean value of 0.82.Limnocharis flava and Sagittaria sagittifolia showed the most effective P adsorption and accumulation ability in all hydrophytes.Statistical analysis of P concentrations of tested hydrophytes indicated that P concentration of shoots ranged from 1415 to 4945 mg·kg-1 and that of roots was 2178～5702 mg·kg-1 with 95% confidence interval,respectively.