不同浓度石油烃对油菜产量、土壤中石油烃残留量及土壤微生物的影响

通过盆栽试验，研究了不同浓度石油污染物对油菜产量、土壤石油烃残留量和土壤微生物区系的影响。研究结果表明：石油烃浓度低于500mg/kg时，可以促进油菜生长，表现为油菜产量增加，但是该石油烃浓度已经严重影响土壤中的微生物种类数量，表现为土壤中的放线菌数量急剧降低，细菌、真菌数量增加，油菜收获后土壤中石油烃含量小于安全值300mg/kg；当浓度超过500mg/kg时，随浓度的增加，对油菜的抑制作用增强，表现为油菜产量降低，土壤石油烃含量大于临界值500mg/kg，土壤细菌数量呈下降趋势、放线菌数量急剧降低、真菌数量变化不明显。综合各类指标，可以暂定在潮土上，石油烃对油菜的临界浓度暂定为500mg/kg。

Impacts of Petroleum pollutants On Rape Bio-mass ,Microbial Population And the petroleum pollutants Residue in soil

By pot experiment, we studied the impacts of petroleum pollutants on rape biomass, microbial population and the petroleum pollutants residue in soil. The results showed that petroleum pollutants could promote rape growth when the petroleum hydrocarbon consistency was below 500 mg/kg, shown as the increase of rape biomass; when the petroleum hydrocarbon consistency was 500 mg/kg, petroleum pollutants had a great influence on microbial population, the amont of actinomycete dramatic decreased, while the amount of bacterium and fungi increased on some degree. After the harvest of rape, the petroleum pollutants residue in soil was below 300mg/kg.When the petroleum hydrocarbon consistency was above 500 mg/kg, growth of rape was inhibited and the biomass of rape decreased. The amount of bacterium presented the downward trend with the increase of petroleum hydrocarbon consistency, the amont of actinomycete kept on decrease, and the amount of fungi was not obviously affected. Consolidating the various indicators, it was tentatively scheduled for alluvial soil, critical concentration of petroleum hydrocarbons on rape was scheduled for 500 mg/kg.