毕业论文终-毛春霞.doc

编号 本科生毕业设计(论文) 题目：铅与酸雨对大豆植株 生物量影响 环境与土木工程 学院 环境工程 专业 学 号 1003080114 学生姓名 毛春霞 指导教师 王丽红 副教授 二〇一二年六月 摘 要 关键词：酸雨；铅；生物量；产量；鲜(干)重 ABSTRACT This paper is engaged in an experiment to explore the com effects of the Lead (Pb) and acid rain (AR) on biomass of water cultured soybean (Glycine max) plants in different growing periods. The results showed that: (1) With the AR or Pb treatment, biomass indexes (leaf area, fresh and dry weight of leaf, stem and root) of soybean seedlings were all decreased, and the lower the pH of AR was or the higher the Pb concentration was, the more serious the damage was. Besides, the response of different organs to the AR or Pb treatment varied, the decrease degree order of biomass was: root stem leaf. It was similar that the damage orders of other growth stages (the beginning pod stage and the beginning seed stage) compared with that of the seedling stage, but the damage degree order was the seedling stagethe beginning pod stagethe beginning seed stage. In addition, during the beginning pod stage, the damage of 90 mg·L-1 Pb treatment was the lowest. (2) In the pH3.0 + Pb groups, the biomass of soybean seedlings was lowest; as the soybean plants grew up, the growth rate of the soybean became slower, leading to the less effects of the combined pollution on soybean, especially in the pH3.0 + low 35 mg·L-1 Pb group. The decrease degree of the biomass of soybean seedlings in the pH3.5 + Pb groups was lower than that in other groups, which was not obvious under other growth stages. In the pH4.5 + Pb (150 mg·L-1) group, the soybean seedlings could not resist the high Pb pollution by its own self-protection. Compared with the control, the number of pods under the beginning seed stage was decreased obviously. Besides, in the AR + Pb groups, the decrease degree of soybean biomass was: rootstemleaf; moreover, compared with AR or Pb treatment, combine