褐土和潮土土壤微生物量氮的测定研究

研究了用碱性过硫酸钾氧化法流动注射分析仪测定褐土和潮土土壤微生物量氮的可行性,并与开氏法进行了比较,同时采用碱性过硫酸钾氧化法测定了河北省不同肥力水平褐土和潮土麦田土壤微生物量氮含量.结果表明:采用碱性过硫酸钾氧化法,可使褐土和潮土浸提液中加入的有机态氮(尿素和EDTA)和铵态氮的回收率达95.33%～100%,与开氏法所测结果基本一致,相关系数达0.99.采用碱性过硫酸钾氧化法测得河北省2大土类不同肥力水平麦田土壤微生物量氮为1.80～66.76 mg/kg,其中褐土为6.39～66.76 mg/kg、潮土为1.80～20.98 mg/kg.

Study on Measuring Methods of Soil Microbial Biomass Nitrogen in the Cinnamon Soil and Chao Soil

The possibility of measuring soil microbial biomass nitrogen(SMB-N) in the cinnamon soil and chao soil by alkaline persulfate method-continuous flow analytical system(CFA)was carried,and was compared with kjeldahl method.At the same time,soil microbial biomass nitrogen was measured of different out,fertility wheat field in Hebei Province.The results showed that firstly,the recovery rate of organic N(Urea-N and EDTA-N)and NH~ _4-N added in soil extraction of different fertility soil were 95.33%-100% by alkaline persulfate method.And the results of alkaline persulfate method and kjeldahl method were consistent with(interrelated coefficient r =0.99).Soil microbial biomass nitrogen of different fertility wheat field were 6.39-66.76 mg/kg by alkaline persulfate method,6.39-66.76 mg/kg in the cinnamon soil,1.80-20.98 mg/kg in the Chao soil.