In order to study solid microbial agent bioremediation for petroleum contaminated soil in Karamay oilfield,the physicochemical properties of soil were analyzed.The optimal bioremediation conditions and the changes of soil microbe quantity,enzyme activity and hydrocarbon component in the process of bioremediation were investigated.The results showed that the Karamay petroleum contaminated soil was silt-based gray desert soil with low H 2 O content,high oil content,weak alkaline,and the available content of three major nutrients (nitrogen,phosphorus and potassium) was low,which was not conducive to the growth of microorganisms.The optimal bioremediation conditions were soil porosity 55%,moisture mass fraction 25%,inoculation amount of microbial agent 5%,nitrogen/phosphorus molar ratio 10 and the addition amount of biosurfactant 0.5%. After 60 d bioremediation under the optimal conditions,the oil content in petroleum contaminated soil dropped from 4.07% to 1.81% with the degradation rate 55.53%,and n-alkanes less than C2 7 were biodegraded obviously.In this process,both the microbe quantity and enzyme activities (dehydrogenase activity, catalase activity and polyphenol oxidase activity ) in the soil were improved.In the bioremediation process,only the improvement of external environment conditions for biostimulation could not effectively remove petroleum hydrocarbons,while the addition of microbial agents for bioaugmentation on the basis was the key factor to remove petroleum pollutants from soil.%分析了克拉玛依石油污染土壤的理化性质，采用固体微生物菌剂对该土壤进行生物修复，考察了最优修复条件及修复过程中土壤微生物数量、酶活性和石油烃组分的变化。结果表明，克拉玛依石油污染土壤是以粉砂为主的灰漠土，含水率低，含油率高，弱碱性，土壤中三大营养元素(氮、磷、钾)的有效含量低，不利于微生物的生长繁殖。最优修复条件为土壤孔隙度55%、含水率25%、固体菌剂添加量5%、氮/磷摩尔比10、生物表面活性剂添加量0.5%，在此条件下经过60 d 的生物修复，含油率由最初的4.07%下降到1.81%，降解率为55.53%，小于C27的正构烷烃得到了明显的降解，土壤中的微生物数量、酶活性(脱氢酶活性、过氧化氢酶活性和多酚氧化酶活性)均有所提高。在生物修复过程中，单靠改善外在环境条件进行生物刺激，无法有效去除石油烃，添加微生物菌剂进行生物强化是去除土壤中石油类污染物的关键因素。
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