中文摘要：

二氧化硫（Sulfur dioxide,SO2）和多环芳烃（Polycyclic aromatic hydrocarbons,PAHs）是山西工矿区同时发现的两种典型环境污染物,对区域土壤环境的影响极大.本文以山西工矿区生黄土为供试土壤,以玉米种子为供试作物,采用室内培养皿育苗试验,研究了不同浓度的SO2（0、10、100、500、1 000 mg kg-1）与PAHs（0、1、10、50、100 mgkg-1）单一及复合污染对玉米种子的萌发率、苗期株高、根长和总生物量的影响,以表征SO2与PAHs复合污染的生态毒性.结果表明,与对照相比,SO2单一污染对玉米种子萌发起到促进作用,对玉米苗期株高、根伸长及早期总生物量则是低浓度（10-100 mg kg-1）促进生长,高浓度（500-1 000 mg kg-1）抑制生长;PAHs单一污染对玉米种子的萌发没有明显的影响,对玉米苗期株高、根伸长及总生物量也是低浓度（1-10 mg kg-1）促进生长,高浓度（50-100 mg kg-1）抑制生长;SO2-PAHs复合污染条件下,只有高浓度的复合污染处理对玉米种子萌发起抑制作用,但与对照相比没有显著性差异;低浓度的SO2与低浓度的PAHs处理对玉米株高、根伸长及总生物量有一定的刺激作用,而高浓度的SO2与高浓度的PAHs处理则抑制了玉米的生长,即随着SO2和PAHs浓度的升高,复合污染的毒性逐渐增强.多元回归分析进一步表明,玉米株高和根伸长主要受SO2和PAHs的共同影响,而玉米苗期总生物量主要受PAHs的影响.

英文摘要：

SO2 （sulfur dioxide） and PAHs （polycyclic aromatic hydrocarbons） are two typical environmental pollutants found at the same time in Shanxi industrial and mining areas. They have a great impact on the regional soil environment. In this study, seed germination, plant height, root elongation and biomass of maize in soils contaminated by SO2 and PAHs with different concentrations were studied to reveal the ecological toxicities of combined pollution. The results indicated that seed germination was slightly improved by the single pollution of SO2. Plant height, root elongation and biomass were slightly improved at lower concentrations （10-100 mg kg-~）, while inhibited at higher concentrations （500-1 000 mg kg-t）. The single pollution of PAHs had no significant effect on seed germination. Plant height, root elongation and biomass were also slightly improved at lower concentrations （1-10 mg kg-~）, while inhibited at higher concentrations （50-100 mg kg-~）. Under the combined pollution conditions, seed germination was inhibited at higher concentrations of SO2-PAHs, but no significant difference was found when compared with the control. Plant height, root elongation and total biomass of maize were slightly stimulated in case of low concentrations of SO2 and low concentrations of PAHs, while they were all inhibited in case of high concentrations. It suggested that the toxicities of combined pollution of SO2 and PAHs gradually increased with increasing concentration of SO2 and PAHs. By using the stepwise regression method, it was showed that plant height or root elongation of maize seedlingswas subject to the combined effect of PAHs and SO2. Meanwhile, PAHs was the main factor which affected the total biomass of maize seedlings under combined pollution conditions. Tab 6, Ref31