甲基溴替代技术对番茄温室土壤养分及微生物量碳的影响

Impact of alternative methyl bromide technology on soil nutrient and microbial biomass carbon in tomato greenhouse

试验干2001--2003年研究了甲基溴替代技术对温室番茄土壤养分及微生物量碳的影响，替代技术为太阳能配合生防制剂木霉菌（SS＋BCA）、甲基溴及减量甲基溴（常规用量75％）覆盖不透膜（MB＋VIF）、威百亩（MS）及减量威百亩（常规用量75％）覆盖不透膜（MS＋VIF）。结果表明：2001～2002年各处理对土壤pH、有效磷、有效钾及阳离子交换量影响不显著，甲基溴熏蒸（VIF膜和PE膜）提高了土壤铵态氮的释放；4个化学处理（MB，MB＋VIF，MS及MS＋VIF）可显著降低土壤微生物量碳含量，但彼此之间差异不显著。2002～2003年增施有机肥后，4个化学处理效果与2001～2002年相同，太阳能消毒则提高了土壤铵态氮的释放，对土壤微生物碳的影响也达到化学处理的水平。两季番茄中土壤微生物量碳均季节性波动明显，施用有机肥可加速微生物的周转。

Four alternative technologies to the use of methyl bromide with ordinary film（ MB ＋ PE）, metham sodium with ordinary film（ MS ＋ PE）, MB and MS dosage reduction by virtually impermeable films（VIF） and soil solarization in combination with selected biological control agents（ SS ＋ BCA）, were chosen for application to an experimental site in Qingzhou, Shandong Province from 2001 to 2003. Soil nutrient indices and microbial biomass C were respectively investigated. Resuits for 2001- 2002 show that soil pH, available P and K and cation exchange capacity（CEC） have no significant difference among the treatment plots. Methyl bromide fumigation measures under PE and VIF prompt release of NH^＋4-N. Soil microbial biomass C decreases after soil disinfection and has no significant difference among treatments with MB ＋ PE, MB ＋ VIF, MS ＋ PE and MS ＋ VIF. Results for 2002 -- 2003, when organic fertilizers were applied, are similar to that for 2001--2002, except that SS ＋ BCA promotes NH^＋4-N release and decreases microbial biomass C. In the two years of 2001 --2003, microbial biomass C shows significant seasonal variation and application of organic fertilizer accelerates microbial biomass C turnover.