产漆酶真菌对高寒草甸土壤有机质矿化特性的研究

Effect of a Laccase Producing Fungus on the Mineralization Characteristics of Soil Organic Matter in Alpine Meadow

为了了解产漆酶微生物真菌对高寒草甸土壤有机质的矿化作用及其特性,实验采用室内密闭静置培养法,对添加产漆酶真菌Marasmius tricolor 310b发酵粗酶液对高寒草甸土壤生物活性有机碳库的影响进行了研究。结果表明:与对照组相比,添加产漆酶真菌Marasmius tricolor 310b发酵粗酶液后,在整个培养期内土壤CO2释放量和微生物生物量碳含量随培养时间的延长,呈现不断下降的趋势,35 d后趋于稳定;在整个培养周期,微生物呼吸熵的变化总体呈对数降低趋势,处理组符合方程y=-9.964ln(x)+32.281(R2=0.9744),对照组符合方程y=-9.788ln(x)+28.683(R2=0.95),处理组土壤CO2的累计释放量始终高于对照组(P<0.05),说明菌株310b促进了土壤有机质矿化作用。土壤有机碳含量在培养前期开始降低,但差异不显著,15 d后处理组的土壤有机碳含量低于对照组(P<0.05),说明不同阶段产漆酶真菌对有机质的周转速率不同,推测产漆酶真菌对有机质的转化作用与土壤环境条件有关。

To understand the mineralization and characteristics of laccase-producing fungi on soil organic matter in an alpine meadow,the effect of fermented crude liquid enzyme of a laccase producing fungus marasmius tricolor 310b on soil biologically active organic carbon pool in an alpine meadow was studied by indoor standing closed culture method.The results showed that compared with the control group,the soil CO2 release and microbial biomass carbon content in the whole culture period showed a decreasing trend with the extension of culture time after the addition fermented crude liquid enzyme of laccase-producing fungus marasmius tricolor 310b,and tended to be stable after 35 days.In the whole culture period,the change of microbial respiration entropy showed a logarithmic decreasing trend.The treatment group conformed to the equation y=-9.964 ln(x)+32.281(R2=0.9744),and the control group conformed to the equation y=-9.788 ln(x)+28.683(R2=0.95).The cumulative release of soil CO2 in the treatment group was always higher than that in the control group(P<0.05),which indicated that strain 310b promoted the mineralization of soil organic matter.The soil organic carbon content began to decrease in the early period of culture,but the difference was not significant.After 15 days,the soil organic carbon content of the treatment group was lower than that of the control group(P<0.05),indicating that the turnover rate of laccase-producing fungi to organic matter is different at different stages.It was speculated that the transformation of laccase-producing fungi on the organic matter was related to soil environmental conditions.