不同种类的湿地植物积累Zn能力的差异及规律研究

为探索不同种类的湿地植物对废水中Zn吸收积累的差异,在人工湿地池中对10种湿地植物吸收积累Zn及其规律进行了研究。结果表明,不同种类的湿地植物间植株Zn浓度相差2.3倍,而植株Zn积累量相差56.6倍,其原因是不同湿地植物间植株生物量(干重)相差51.8倍。相关性分析表明,不同湿地植物的Zn积累量与植株Zn浓度间无明显关系,而与植株生物量间相关性达极显著水平。该结果说明,在处理Zn污染废水的湿地技术中,选择适宜的湿地植物种类对处理效果有很大影响。而选择高积累Zn湿地植物的首要指标是植物体的生物量,其次才是植株Zn浓度。本研究筛选出了5种对废水中Zn积累量高的湿地植物。

Variations among Wetland Plant Species in Zn Accumulation and Their Rules

In order to investigate the differences among wetland plant species in the uptake of Zn from wastewater,the accumulation of Zn in ten wetland plant species and the rules are studied in constructed wetlands.The results show that the difference among the plant species is 2.3 times for Zn concentrations in the plants,but as large as 56.6 times for Zn accumulations,for the variation among the plant species in plant biomass(dry weight) is more than 50 times.Relevant analysis indicates that the accumulations of Zn in wetland plants are not obviously related with Zn concentrations in the plants,but significantly with plant biomass.These results demonstrate that selection of suitable wetland plant species in the wetland for treatment of Zn-polluted wastewater will affect significantly the efficiency of wastewater treatment.The first index for high Zn accumulating wetland plant species is biomass,and the second index Zn concentration in plant.Five high Zn accumulating wetland plant species are screened out.