植物-微生物联合修复石油污染土壤的实验室模拟

Laboratory simulation of plant-microbe combination repair of petroleum-polluted soil

对冰草、紫花苜蓿、冬小麦进行了为期63 d的实验室模拟,通过测定土壤脱氢酶活性、微生物数量以及土壤残油率的变化,分析了植物-微生物联合作用对不同质量分数土壤石油烃污染的修复效果,以期为后期的现场修复提供理论依据.结果表明：在石油烃质量分数为3%时,植物-微生物联合可使石油烃降解率达到84%-87%;3种植物的降油效果依次为紫花苜蓿〉冰草〉冬小麦,紫花苜蓿组最高石油降解率可达86.47%.在石油烃质量分数达到10%时,微生物的生长受到明显阻碍,土壤脱氢酶活性也大大降低,从而导致植物-微生物联合修复受阻,植物表现为生长缓慢,植物茎叶变小、微黄.因此,植物-微生物联合体系中,石油烃质量分数为3%时能促进微生物的繁殖,提高土壤中脱氢酶活性,促进植物和微生物对石油烃污染物的降解,加速油污土壤的修复作用.

The experiment selected the Agropyron cristatum,Medicago sativa L.,and Triticum aestivum,for a63-day laboratory simulation,measured the activities of soil dehydrogenase,the number of microbes in soil,and the changes in petroleum residual rates,and analyzed the remediation effects of plant-microbe combination repair in different petroleum densities,hoping to provide a theoretical basis for future remediation cases.The result showed that the plant-microbe combination repair could make the petroleum degradation rates reach to 84%-87%when the petroleum dcnsity was 3%.The three kinds of plant degradation effects were：Medicago sativa L.〉 Agropyron cristatum Triticum aestivum,and the Medicago sativa L.＇s petroleum degradation rate was up to 86.47%.When the petroleum density reached 10%,it was obvious that the microbe growth had been inhibited,and the activities of soil dehydrogenase was also greatly reduced.Thus inhibiting the plant-microbe combination repair,the plants growth became slow,the stems and leaves became smaller and turned a little yellow.Therefore,in the system of plant-microbe combination repair,the 3%petroleum density could promote the microbe growth,increase the activities of soil dehydrogenase,and promote the petroleum degradation of plants and microbes,accelerating the degradation effects of petroleum pollutants.