【作者】 彭晓赟；

【导师】 赵运林；

【作者基本信息】 湖南农业大学 ， 植物学， 2009， 硕士

【摘要】 为研究水生植物修复湿地中重金属污染的问题,本试验选择洞庭湖中的乡土优势植物菰,对其在重金属镉单一污染及有机污染物p,p’-DDT与重金属Cd复合污染下进行耐性试验和富集试验,并在这两种污染土壤中通过添加改良剂(石灰和有机肥菜枯)的方式研究重金属镉对其生长发育、生理生化的影响,进一步研究了改良剂对重金属镉污染的富集效应。主要研究结果如下:单一Cd污染条件下随着Cd浓度的增加,菰的生长受到严重的抑制,表现为叶绿素含量降低;可溶性糖含量先升高后下降;植株地上部分和地下部分钾的含量均表现出低浓度下的促进而高浓度下的抑制;植株地上部分和地下部分锌积累量均随重金属Cd浓度的增多而减小。有机污染物p,p’-DDT与重金属Cd复合污染条件下,随着Cd浓度的增加,菰的株高、地上部干重和地下部干重均要低于单一污染条件下,说明复合污染对菰的毒害更大。Cd在菰植株体内的分布规律为地下部分＞地上部分。复合污染条件下,Cd的迁移能力发生变化,在复合污染条件下,菰植株体内Cd的含量升高,随着Cd浓度的增加,升高的越多。添加等量的改良剂(石灰和有机肥菜枯)虽然未能完全消除Cd污染对菰植株毒害,但其毒害程度有所减轻。石灰和有机肥菜枯这两种改良剂能不同程度的提高土壤pH值,降低土壤中有效态重金属含量,从而显著地抑制了Cd向菰地上部的转移,降低了重金属在菰地上部植株中的积累,改善了菰的生长和发育。并且石灰在治理污染时效果要优于有机肥菜枯。更多还原

【Abstract】 To research remediation effect of aquatic plants on heavy metal pollution in marsh, the native dominant plant Zizania latifolia Turcz. in the Dongting lake was selected for this experiment. Endurance test and accumulation test of Z. latifolia Turcz. were conducted under two different treatment soils: soil polluted only by heavy metal Cd and soil polluted by Cd and organic pollutant p,p ’-DDT. Cd effect on plant development、physiology and Biochemistry were studied under amendment addition of lime and organic manure to research amendments’effect on heavy metal accmulation, Main conclusions were listed as follows:With increase of the concentration of Cd, Z. latifolia Turcz. growth was severely inhibited under single Cd polluted. The inhibited effect showed in follow aspects: chlorophyll content decreased; Soluble sugar content increased in the lower Cd concentration treatment and decreased in the higher Cd concentration treatment; Potassic content in both aboveground part of plant and underground part of plant were stimulated in lower concentration and which were inhibited in higher concentration; Zinc concentration in both aboveground part of plants and underground parts of plant decreased as the Cd concentration increased.With increase of the concentration of Cd, the plant height, dry weight of aboveground biomass and underground biomass in treatment with organic pollutant p,p ’-DDT and heavy metal Cd were lower than that in the treatment with single heavy metal Cd. The results indicated that complex pollution was more toxic than single pollution for Z. latifolia Turcz.Underground part of plants had more Cd content than that in aboveground part. Cd migrating capacity changed in complex polluted treatment. Cd content in Z. latifolia Turcz increased as the Cd concentration increased and the increased extent was more under high concentration Cd than under low concentration Cd treatment.Amendments addition can not completely eliminate but partly decrease Cd toxicity on Z. latifolia Turcz. The reasons were that amendments(lime and organic manure ) can increase soil pH and mitigate available heavy metal content in the soil. And Cd migrating capacity significantly inhibited from underground part of soil to aboveground part of soil,accumulation of Cd in aboveground part of soil decreased, which improved development and growth condition of Z. latifolia Turcz. Meanwhile, lime had a better effect than organic manure in pollution remediation.更多还原