重金属污水对不同湿地植物种子萌发的影响

为探讨湿地植物种子在重金属污染湿地植被恢复中的应用,以17种临沂地区常见湿地植物种子为材料,研究了不同浓度重金属污水对其萌发的影响。结果表明:随着重金属污水浓度的增加,萌发率、萌发指数及活力指数,除了芦苇、芦竹、风车草、黄菖蒲、灯芯草、泽泻和石龙芮,其他均呈现先升高后降低的趋势,浓度越高受到的抑制越明显,且在T3和T4处理下均显著低于对照(P0.05);重金属污水对活力指数的抑制作用大于对萌发率和萌发指数的抑制;17种供试湿地植物种子普遍对重金属污水有一定的耐性;通过隶属函数值聚类分析,将供试植物在种子萌发期划分为耐重金属污水较好、中等和较差3种类型,其中黄菖蒲和黄花蔺耐性较差,12种植物耐性中等,香蒲、小香蒲和芦苇耐性较好,说明这3种植物在种子萌发期对重金属污水具有较强的抗性,在利用植物种子修复重金属污染湿地中可优先作为选择的材料。

Influence of heavy metal waste water on seed germination of different wetland plants

Our objective was to explore the germination of wetland plant seeds in heavy metals waste water.Seventeen species of wetland plant seeds were collected and incubated in the waste water with different heavy metal concentrations.The results showed that the germination rate, germination, index and vigor index of 10 seeds increased at first and then decreased with increasing heavy metal concentrations except Phragmites caustralis, Arundo donax, Cyperus alternifolius, Lris pseudacorus Linn, Juncus effuses, Alisma plantago-aquatica, Ranunculus sceleratus L.The higher the concentration, the more obvious inhibition was observed.All the parameters in both T3 and T4 were significantly lower than those of the control(P>0.05).The inhibition to the vitality index was greater than the germination rate and germination index.All the seeds had certain resistance to heavy metal stress.The cluster analysis of the membership function integrated values showed that the test plants were divided into 3 categories with high, medium and low resistance to heavy metal stress during germination.Both Lris pseudacorus Linn and Limnocharis flava were lowest resistant to heavy metals.Twelve species were middle resistant.Typha orientalis, Typha minima, Phragmites caustralis were highest resistant to heavy metals, suggesting that they might be suitable to grow in the wetland contaminated with heavy metals.