Abstract: Utilizing crushed forage straw or planting green manure forage grass is the most economical and effective biological measures for the remediation of petroleum contaminated soil. The remediation effects of nine kinds of forage straws on the biochemical properties of petroleum-contaminated soil including the microbes, soil enzyme activities and nutrient availability were studied in this paper by collecting typical wasteland soil in petroleum-contaminated areas of northern Shaanxi. Results showed that all six kinds of forge straws contributed to the soil respiration and growth of microbes, promoted urease, alkaline phosphatase and dehydrogenase activities, increased the contents of soil available potassium, available Mn and available zinc, and decreased the soil pH value and catalase activity to some extent in three levels of petroleum-contaminated soil. Comprehensive analyses indicated that in light pollution, the straw of Festuca rubra had the best repair effect on the biochemical properties of petroleum-contaminated soil, followed by Coronilla varia and Astragalus adsurgens. In middle pollution, only Medicago sativa straw had significant remediation effect on the biochemical properties of petroleum-contaminated soil. In severe pollution, the straw of Medicago sativa had the best repair effect on the biochemical properties of petroleum-contaminated soil, followed by Festuca rubra and Coronilla varia straws.

Key words: Petroleum-contaminated soil, Soil remediation, Forage straws, Soil microorganisms, Soil enzyme, Soil nutrient

摘要： 利用牧草秸秆或直接种植绿肥牧草是修复石油污染土壤最经济有效的生物措施。通过采集陕北石油污染区典型荒地土壤，分别以3种石油污染水平油土混合培养后，施入当地6种常见牧草秸秆粉碎样品进行分解培养试验，检测不同牧草秸秆对油污土壤的微生物、酶活性和养分有效性等生物化学性质的修复效应，并利用主成分分析法综合分析修复效果。结果表明：6种牧草秸秆处理均可在一定程度上促进3种水平油污土壤微生物的生长和繁殖，提高土壤脲酶、碱性磷酸酶和脱氢酶活性，增加土壤速效K、有效Mn和有效Zn含量，降低土壤pH值和H₂O₂酶活性。综合而言，轻度污染时，紫羊茅（Festuca rubra）秸秆修复效果最好，其次为小冠花（Coronilla varia）和沙打旺（Astragalus adsurgens）；中度污染时，只有苜蓿（Medicago sativa）具有明显的修复效果；重度污染时，苜蓿的修复效果最好，其次为紫羊茅和小冠花。

关键词: 石油污染土壤, 土壤修复, 牧草秸秆, 土壤微生物, 土壤酶, 土壤养分