设施土壤微生物学特性变化研究

采用定点取样的方法，研究了不同种植年限设施土壤微生物主要类群、生物量碳和5种酶活性的变化特点，结果表明：（1）不同种植年限设施土壤微生物主要类群随季节变化不一致，细菌数量先升后降，高峰出现在6月，10月最低；真菌和放线菌数量均在3月最多，而后逐渐减少。随设施种植年限的延长，微生物总数逐渐增加，但真菌和放线菌占微生物总数的比例却呈下降趋势。与露地相比，设施栽培中真菌增加快于细菌。（2）不同种植年限设施土壤微生物生物量碳在3月和6月含量最高，随设施种植年限的延长，微生物生物量碳含量也增加。（3）不同种植年限设施土壤酶活性季节变化明显，除过氧化氢酶外，脲酶、酸性磷酸酶、中性磷酸酶和转化酶活性高峰主要出现在3月，土壤酶的总体活性随设施种植年限的延长有所下降。

Study on Changes of Microbial Characters in Greenhouse Soil

Through the method of fixed-point sampling,changes of microbial strains,microbial biomass carbon and five enzymes activities in greenhouse soil with different years cropping were evaluated.The results showed :(1) Changes of seasonal microbial strains were imcompatible with seasons in different years greenhouse cropping.The amount of bacteria increased firstly and then decreased,the highest amount appeared in June,while December was the lowest.The hightest amounts of actinomyces and fungi were in March,then declined gradually with seasons.The amount of microorganism became higher with years,while the percent of actinomyces and fungi to that one were lower.Compared with open field,the amount of fungi were incread more faster than bacteria in greenhouse cropping.(2) The hightest contents Of microbial biomass carbon occurred in March and June,and incread with different years greenhouse cropping.(3)Changes of seasonal soil enzyme activities were obviously with seasons in different years greenhouse cropping.Except catalase,the maximum enzyme activities of urease,acid phosphatase,neutral phosphatase and invertase occurred in March,the total enzyme activities were declined with years.