阿什河流域10种水生植物对水质氮磷的净化能力比较

摘要

阿什河是松花江重要的一级支流,水环境污染问题最为突出.针对阿什河流域氮磷污染严重、水质恶化、生物多样性低等问题,选取千屈菜(Lythrum salicaria)、菖蒲(Acorus calamus)、泽泻(Alisma plantago-aquatica)、慈姑(Sagittaria trifolia)、芦苇(Phragmites australis)、菰(Zizania latifolia)、显脉苔草(Carex kirganica)、水葱(Scirpus validus)、狭叶香蒲(Typha angustifolia)、香蒲(Typha orientalis)10种阿什河流域常见植物作为研究对象,在室内静水条件下对其氮磷富集和水质净化的能力进行比较研究.结果表明:①不同植物净增生物量之间具有显著差异(P<0.05),生物量的变化范围为492.71~939.19 g∕m2,其中净增生物量最高的泽泻是最低的慈姑的1.91倍.②不同植物的植株茎叶部和根部的氮、磷含量也具有一定的差异,茎叶部TN含量(以质量分数计)为3.46~19.55 mg∕g,TP含量为1.34~4.77 mg∕g;根部TN含量为3.88~13.59 mg∕g,TP含量为1.16~7.59 mg∕g;TN、TP在茎叶部的富集能力均大于根部,有效刈割是彻底去除污染物的有效手段.③在水体中TN、TP浓度(以质量浓度计)为2.08~3.03、0.56~0.77 mg∕L时,不同植物对水质的净化能力也存在一定的差异,不同植物对TN、TP的去除率为64.96%~86.03%、64.64%~85.12%.④不同植物TN、TP富集贡献率范围分别为50.24%~80.71%、54.85%~93.44%.研究显示,植物净增生物量湿质量、干质量均与TP富集率相关性较高,可以作为植物筛选的一个重要的参考因素;水葱、芦苇、菰和千屈菜可作为阿什河流域生态修复的备选植物.%Ashi River is an important tributary of Songhua River and its water pollution become most servious than others. Aiming at the problem of pollutions of nitrogen(N) and phosphorus(P) and biodiversity decreasing,we studied the enrichment ability of N and P and water purification under indoor hydrostatic conditions about ten common plants of Ashi River, which are Lythrum salicaria, Acorus calamus,Alisma plantago-aquatica,Sagittaria trifolia, Phragmites australis, Zizania latifolia, Carex kirganica, Scirpus validus, Typha angustifolia and Typha orientalis. The results showed that:(1) The net accumulated biomass of different plants(range from 492.71 g∕m2 to 939.19 g∕m2) were changed significantly(P<0.05),in which the highest net accumulated biomass of A. plantago-aquatica was 1.91 times higher than the lowest plant of S. trifolia;(2) There was a little different in N and P concentration of root,stem-leave of different plants. The range of total N and P contents of stem-leaf were 3.46-19.55 and 1.37-4.77 mg∕g respectively,and of root were 3.88-13.59 and 1.16-7.59 mg∕g, the enrichment ability of stem-leaf was greater than that of root, efficient mowing is the most effective way to thoroughly remove contaminants;(3) When the concentrations of TN and TP in water was between 2.08-3.03 and 0.56-0.77 mg∕L,the water purification ability was a little different among these ten plants. The removal efficiency of the TN and TP were 64.96%-86.03% and 64.64%-85.12%. (4) The contribution rate of enrichment efficiency of TN and TP for aquatic plant was 50.24%-80.71% and 54.85%-93.44%. The P enrichment efficiency which can be used an important index to plant choosing,correlated significantly with plant net and wet accumulated biomass,S.validus,P.australis,Z.latifolia and L.Solitary can be used to be ecological remediation plants in Ashi Rive Basin.