表面活性剂LAS与重金属Cd复合污染对黄豆生长的影响

Complex Effects of LAS and Cd on Growth of Soybean

采用盆栽试验方法,研究了表面活性剂LAS(十二烷基苯磺酸钠)与重金属Cd单一及复合污染对黄豆生长和生理生化指标的影响。结果表明,在单一LAS污染条件下,较低浓度的LAS(≤15mg·L-1)能促进黄豆的生长,较高浓度的LAS(≥50mg·L-1)对黄豆有毒害作用。在单一Cd污染条件下,土壤中Cd浓度为5mg·kg-1和10mg·kg-1时,黄豆的生长受到严重的抑制。在同一Cd污染土壤中,随着灌溉水LAS浓度的升高,黄豆的株高、干重、叶片叶绿素含量和SOD活性都呈先升后降的趋势,当LAS浓度为50mg·L-1时,这些指标的数值最大,而MDA含量随着LAS浓度的升高呈先降后升的趋势。通过这些生长及生理生化指标的测定,可以得知低浓度LAS(≤50mg·L-1)能部分缓解Cd对黄豆的毒害。

Effects of single and complex pollution of dodecyl benzene sulfonic acid sodiumsalt( LAS) and cadmium on the growth of soybean( Clycine max) were studied with pot culture experiments. The results showed that the lower concentrations( ≤ 15 mg· L- 1) of LAS could promote soybean growth, while LAS was toxic to soybean at higher concentrations( ≥ 50 mg· L- 1) . The growth of soybean was seriously inhibited in the soils with 5 and 10 mg· kg- 1 of Cd. The plant height, dry weight, chlorophyll content and superoxide dismutase( SOD) activity of leaves increased first, then decreased with increasing LAS concentrations in the same Cd- polluted soils; while the content of malondialdehyde( MDA) in leaves decreased first and then raised slightly with increasing LAS concentrations. The maximum values of these indexes appeared at the solution with 50 mg· L- 1 LAS. According to the change of these indexes, lower concentrations of LAS( ≤ 50 mg· L- 1) can partly mitigate the toxicity of Cd to soybean plants.