5种湿地植物对含盐生活污水的净化效果及其生理响应

Purifying effects and physiological response of five wetland plants to saline domestic sewage

为了明确湿地植物对含盐生活污水的净化效果及其生理响应,本研究以芦苇(Phragmites australis)、千屈菜(Lythrum salicaria)、水莎草(Juncellus serotinus)、石菖蒲(Acorus gramineus Soland)和灯心草(Juncus effusus L.)为试验材料,探究含盐生活污水对这5种湿地植物生长、光合作用及抗氧化系统的影响,并对其净化效果进行评价。结果表明,含盐生活污水抑制了5种湿地植物的生长和光合作用,其中,芦苇受抑制程度最轻,与对照相比,其株高、根长、干质量、净光合速率(Pn)、气孔导度(Gs)、胞间二氧化碳浓度(Ci)和蒸腾速率(Tr)分别降低30.84%、16.96%、23.41%、23.73%、26.72%、27.86%和25.51%。含盐生活污水提高了5种湿地植物的丙二醛(MDA)含量和抗氧化酶活性,其中,芦苇的MDA含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性及抗坏血酸过氧化物酶(APX)活性分别较对照提高了65.03%、38.51%、44.76%、58.90%和60.79%。5种湿地植物均可显著提高含盐生活污水中化学需氧量(COD)降低率以及铵态氮(NH+4-N)、总氮和总磷的去除率。其中,芦苇和千屈菜净化效果最佳,灯心草次之,水莎草和石菖蒲净化效果最差。将芦苇、千屈菜和灯心草随机组配成4种组合,芦苇-千屈菜-灯心草组合对含盐生活污水的净化效果最佳,COD降低率、NH+4-N去除率、总氮去除率和总磷去除率分别达到80.96%、84.95%、82.65%和84.18%。本研究结果可以为湿地植物在含盐生活污水净化中的应用提供了理论依据。

To study the purifying effects and physiological response of five wetland plants to saline domestic sewage,Phragmites australis,Lythrum salicaria,Juncellus serotinus,Acorus gramineus Soland and Juncus effusus L.were selected as experimental material.In addition,effects of saline domestic sewage on the growth,photosynthesis and antioxidant system of wetland plants were investigated,and the purifying effects were evaluated.The results showed that the growth and photosynthesis of five wetland plants were inhibited under saline domestic sewage stress,and the inhibitory degree of reed was the least.Compared with control,the plant height,root length,dry weight,net photosynthetic rate(Pn),stomatal conductance(Gs),intercellular carbon dioxide concentration(Ci)and transpiration rate(Tr)of reed were decreased by 30.84%,16.96%,23.41%,23.73%,26.72%,27.86%and 25.51%,respectively.The content of malondialdehyde(MDA)and the activities of antioxidant enzymes in five wetland plants were increased under saline domestic sewage stress.Compared with control,the MDA content and the activities of superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),ascorbate peroxidase(APX)of reed were increased by 65.03%,38.51%,44.76%,58.90%and 60.79%,respectively.The reduction rate of chemical oxygen demand(COD),removal rates of NH+4-N,total nitrogen and total phosphorus in saline domestic sewage were significantly increased by five wetland plants.The purifying effects of wetland plants followed the order of Phragmites australis and Lythrum salicaria>Juncus effusus L.>Juncellus serotinus and Acorus gramineus Soland.Four combinations were randomly composed by Phragmites australis,Lythrum salicaria and Juncus effusus L..The Phragmites australis-Lythrum salicaria-Juncus effusus L.had the best purifying effect on saline domestic sewage,and the reduction rate of COD,removal rates of NH+4-N,total nitrogen and total phosphorus were 80.96%,84.95%,82.65%and 84.18%,respectively.The results of this study can provide theoretical basis for the application of wetland plants in the purification of saline domestic sewage.