【作者】 辛玉玲；

【导师】 易秀；

【作者基本信息】 长安大学 ， 环境工程， 2007， 硕士

【摘要】 研究土壤中重金属的复合污染对植物生长发育及其产生的生态效应,对揭示重金属复合污染机理、评价环境质量及采取合理的污染防治措施具有十分重要的理论意义和实际价值。本文选择铬和砷作为研究对象。利用黑麦种子发芽试验、盆栽试验,通过观察种子的发芽情况、植物的生长情况(株高、鲜重等)和植物体内的生理指标的变化来确定铬、砷及其交互作用对植物生长的影响,并通过土壤吸附试验阐明土壤对铬和砷的吸附规律,从而判断铬、砷及其交互作用对土壤和植物的生态效应。通过试验得出以下结论:(1)土壤吸附试验表明,土壤对Cr(Ⅵ)、As(Ⅴ)的吸附量分别随着处理浓度的增大而增大,吸附率均呈下降趋势;交互处理中,高浓度Cr(Ⅵ)(大于10mg/L)的加入使得土壤对As(Ⅴ)的吸附能力降低;低浓度Cr(Ⅵ)(小于10mg/L)对土壤吸附As(Ⅴ)的能力几乎没有影响;当Cr(Ⅵ)的处理水平小于10mg/L,As(Ⅴ)的加入对土壤吸附Cr(Ⅵ)的能力有影响。(2)种子发芽试验表明,Cr(Ⅵ)处理浓度在0～120mg/L时,可以促进黑麦种子的发芽,而As(Ⅴ)在0～100mg/L之间则产生抑制作用;交互处理中,Cr(Ⅵ)的加入会减缓As(Ⅴ)对黑麦种子发芽的抑制作用;As(Ⅴ)的加入会阻碍Cr(Ⅵ)对黑麦种子发芽的促进作用。(3)盆栽实验结果表明:1)随着As(Ⅴ)处理浓度(0～70mg/kg之间)的增大,植物样中的As含量也随之增大;As(Ⅴ)对黑麦出苗、生长发育、叶绿素合成和细胞膜结构都有刺激作用,随着As(Ⅴ)浓度的增大刺激作用逐渐减弱;2)不同处理浓度(0～100mg/kg)的Cr(Ⅵ)都会对黑麦出苗、株高、鲜重有毒害作用,同时对细胞膜结构有破坏作用,但能刺激光合作用,促进叶绿素a、b的生成;3) Cr(Ⅵ)、As(Ⅴ)交互处理产生的生物效应很复杂,但对黑麦产生的效应总体趋势是Cr(Ⅵ)的影响比As(Ⅴ)大。更多还原

【Abstract】 To study on the growth and development of plant and which produces ecological effect compound pollution of heavy mental in soil has theoretical significance and practical worthiness to announce the mechanism of compound pollution and ecological effect,evaluate the environmental quality and operate reasonable countermeasures to heavy mental pollution.Chromium(Cr) and Arsenic(As) have been selected as the study objects.Though the observation on burgeon situation,development situation(stem length,fresh weight) and the changes of physiologic indexes in plants from burgeon test and potted test of rye,the effect of Cr(Ⅵ)、As(Ⅴ) and Cr(Ⅵ)-As(Ⅴ) interaction on plant development are ascertained.The absorption rules of soil to Cr(Ⅵ) and As(Ⅴ) are set forth by soil adsorption test,accordingly, the ecological effect on soil and plant are judged,the conclusions from the tests as following:(1) the soil absorption test indicates that the adsorption quantities of Cr(Ⅵ) and As(Ⅴ) increase respectively with increase of managing density,the absorptivities are prone to reduce; In the treatment of interaction course,the absorption of As(Ⅴ) is reduced by the input of Cr (Ⅵ) high density(higher than 10mg/L) and the low density(lower than 10mg/L) nearly has no effect,the input of As(Ⅴ) do has influence to the soil absorption of Cr(Ⅵ) when the treatment level of Cr(Ⅵ) lower than 10mg/L.(2) the burgeon test indicates that burgeon of rye seeds has been accelerated when treatment density of Cr(Ⅵ) between 0 to 120mg/L while been restrained when treatment density of As(Ⅴ)between 0 to 100mg/L;In the treatment of interaction course,the input of Cr (Ⅵ) will reduce the restrained function of As(Ⅴ) and the input of As(Ⅴ) will reduce the accelerated function of Cr(Ⅵ).(3) conclusions from the potted test as following:1) The content of As(Ⅴ) in the plant samples increases with the treatment density of As(Ⅴ)(between 0 to 70mg/kg);seeding emergence,growth and development,chlorophyl compound and structure of cell membrane are activated by the input of As(Ⅴ),the effect gradually reduces with the activation;2)The seeding emergence,stem length and fresh weight are poisoned and the structure of cell membrane of rye are destroyed while the photosynthesis is activated and chlorophyll a and b are accelerated by treatment density(between 0 to70mg/kg) at different level;3) The biological effect of Cr(Ⅵ)-As(Ⅴ) interaction is very complicated,the trend of Cr(Ⅵ) effect on rye is greater than that of As(Ⅴ).更多还原