摘要
通过纯培养试验、室内培养试验和水稻盆栽试验研究了稀土元素镧对红壤微生物区系的影响 .结果表明 :镧对纯培养细菌、放线菌、真菌均有较强的毒害作用 .对镧的敏感性顺序为 :放线菌 >细菌 >真菌 .在低浓度下 ,镧对土壤细菌、放线菌、真菌的作用不明显 ,在高浓度下 ,表现为抑制作用 .在低浓度下 ,镧对土壤硝化细菌有强烈的刺激作用 ,最大刺激率达到 70 % ,随着浓度的升高则产生抑制作用并不断增强 .镧对土壤反硝化细菌作用不明显 .在低浓度下 ,镧对土壤自生固氮菌有某些刺激作用 ,随着浓度的升高 ,则产生显著的抑制作用 .土壤硝化细菌可以作为稀土对作物增产效应的指示菌 ,硝化细菌和自生固氮菌可以作为稀土污染土壤生态环境的指示菌 .外源稀土对红壤微生物区系产生抑制作用的临界浓度在 1 50 mg/ kg左右 .
The effect of Lanthanum(La) on the microflora of red soil was studied by pure culture,soil culture and rice pot culture experiment.La was poisonous to soil bacteria,actinomyces and fungi in pure culture experiment,the sensitivity of which to La was decreased in order of actinomyces>bacteria>fungi.La had no significant effect on soil bacteria,actinomyces and fungi at low concentration while had inhibitory effect at high concentration.La had stimulative effect on soil nitrifier at low concentration and the maximum stimulation ratio reached 70 percent while had inhibitory effect at high concentration and the inhibition was strengthened with increasing concentration.La had slightly stimulative effect on soil azotobacter at low concentration while had inhibitory effect at high concentration.La had no significant effect on soil denitrifier.Nitrifier could be used as indicator bacteria of the biological effect of rare earth,nitrifier and azotobacter could be used as indicator bacteria of rare earth\|polluted soil,the critical concentration was about 150mg/kg.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2000年第6期28-31,共4页
Environmental Science
基金
国家自然科学重大基金!资助项目 (2 9890 2 82 )
