污泥和盐渍土混配介质的性质及对5种野生植物生长的影响

Physical and Chemical Properties of Mixtures of Sludge and Saline Soil and Their Effects on Growth of Five Species of Wild Plants

将污泥与滨海盐渍土按照不同比例(污泥质量分数分别为0、20%、40%、60%、80%和100%)混配,开展三叶鬼针草(Bidens pilosa)、稗(Echinochloa crusgalli)、荆芥(Schizonepeta tenuifolia)、金叶马兰(Kalimeris indica)和蒲公英(Taraxacum mongolicm)5种野生植物的盆栽试验,研究污泥混配介质的理化性质,污泥比例对植物成活率、叶绿素含量和干质量的影响,以及植物体内各种重金属的累积浓度,探索污泥在滨海区盐渍土中的最佳施用比例,并对野生植物资源进行评价。结果表明,污泥改良滨海盐渍土是可行的,污泥质量分数为20%～60%时,混配介质的理化指标符合CJ/T 340—2011《绿化种植土壤》,Cd、Cu、Zn、Cr、Pb和Ni含量符合GB 15618—95《土壤环境质量标准》中的二级标准,并以60%污泥+40%滨海盐渍土的质量配比效果最佳,该混配介质中植物存活率达100%;三叶鬼针草、稗子、荆芥、金叶马兰和蒲公英是上海市滨海地区优良的植被恢复先锋植物。

Feasibility of the application of sludge to amelioration of coastal saline soil was studied through a pot experi- ment using 5 species of wild plants, Bidens pilosa, Echinochloa crusgalli, Schizonepeta tenuifolia, Kalimeris indica and Taraxacum mongolicm. Mixtures of sludge and coastal saline soil were prepared with the former accounting for 0, 20% , 40% , 60% , 80% and 100% , separately. In order to explore for the most suitable application ratio of the sludge to the soil and appraise the wild plant resources, physicochemical properties of the mixtures were determined and effects of the mixtures on survival rate, chlorophyll content and dry weight of the plants analyzed, and cumulative concentrations of heavy metals in the plants measured. Results show that it is feasible to use the sludge to ameliorate the coastal saline soil, when the concentration of sludge was between 20% - 60% , the physicochemical properties of the mixtures satisfied ＂Planting Soil for Greening＂ （ CJ/T 340--2011 ）. The optimal sludge-soil ratio is 60% ： 40% , and the survival rate of plants is 100%. Bidens pilosa, Echinochloa crusgalli, Schizonepeta tenuifolia, Kalimeris indica and Taraxacum mongolicm arc excellent pioneer plant species in restore vegetation in the coastal area of Shanghai.