我省主要土壤微生物数量及其肥力状况分析

本文采用分析对比法测定了土壤中好气性细菌、放线菌、霉菌以及土壤蓝藻的细胞量;还测定了包括好气性固氮菌、纤维素分解菌、硝化细菌和氨化细菌四类群具有生理活性的微生物。同时,对土壤的主要农化性状进行了分析。试验表明,土壤肥力状况同微生物数量呈正相关。土壤肥力差异是灌漠土>黑垆土>黄绵土。亚高山草甸土虽然含有机质较多,微生物总量却较小。各类土中的微生物总数多达一亿个/克干土以上。其中细菌约占95%,放线菌占4%,霉菌和蓝藻较少。灌漠土和黑垆土含有较多的好气性固氮菌、纤维素分解菌,表明了该类土壤具有良好的肥力性状和熟化程度较高。

Analysis of Main Soil Microorganisms and its Fertility in Gansu

The present paper deals with correlation between content of soil microorganisms and fertility of five groups main soil in Gansu.The studies during 1982—1985 indicated as foll -ows:1.The total amount of microorganisms is more than 10 per gram of dry soil in five soil groups determinate while mold and blue algae are quite few in the total amount- The correlation between the tolal amount of mircoorganisms and soil fertility is positive in cropped soils,The results are arranged in the following order:zhangye irregated desert soil>Qingyang ortho heilu soil>Wuwei irregated desert soil>Dingxi yellow mein soil among cropped soils,The content of microorganisms in Tianzhu sunalpine meadow soil is very low 2.The useful microbial group differ in five determinate soils,3.The cellulose-decomposing bacterium and nitrogen-fixing bacterium in the determienate soils coincide in number.