Three arsenic⁃resistant strains of fungi were isolated and identified as Chaetomiumglobosum, Alternaria tenuissi⁃ma and Scheffersomyces stipitis from arsenic contaminated soils, and tested for tolerance of the strains to As and effects of the treatment of As⁃contaminated soils with the strains on soil As bio⁃availability relative to duration of the exposure to and inoculation rate of the fungi. Results show that the three strains were quite good in tolerance to As5+ in the range of 5-100 mg·L-1 As5+ and displayed an order of Scheffersomyces stipitis > Alternaria tenuissima > Chaetomium globosum. When As concentration was in the range of 5-10 mg·L-1 , Scheffersomyces stipitis was somewhat promoted in growth. Within the first 30 days of the inoculation of the three strains, soil bio⁃available As increased by 137�2, 77�9 and 36�5 times, respective⁃ly, as compared with CK. Their effects on soil As varied with their inoculation rate, displaying a rising trend with the rate and a positive relationship.%从砷污染土壤中分离出3株对砷具有耐受性的真菌菌株，考察了菌株对砷的耐受能力及菌体处理污染土壤时间、菌体投加量对土壤生物砷有效性的影响。经鉴定，3种菌株分别为球毛壳霉（ Chaetomium globosum）、细极链格孢（ Alternaria tenuissima）和木糖发酵酵母（ Scheffersomyces stipitis）。结果表明：3种菌株对ρ为5～100 mg·L－1的砷具有良好的耐受性，且耐受性从大到小依次为木糖发酵酵母、细极链格孢和球毛壳霉；ρ为5～10 mg·L－1的砷对木糖发酵酵母的生长有一定的促进作用，30 d内土壤生物有效态砷含量与对照相比分别提高137�2、77�9和36�5倍；不同浓度菌体对于土壤砷具有不同的作用效果，土壤有效态砷含量随球毛壳霉、细极链格孢和木糖发酵酵母投加量的增加而增加，且两者呈正相关。
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