长期定位施氮对连作番茄土壤可培养微生物数量的影响

以蔬菜长期定位施肥试验为基础,采用选择性培养基培养微生物,研究长期施氮对连作番茄土壤微生物的组成及数量的影响,并测定了土壤养分,探讨了土壤微生物与土壤养分的相关性。结果表明:处理AN0土壤好气性固氮菌数量最多,显著高于其他处理,处理AN1和BN2显著低于其他处理,施用有机肥可提高土壤中好气性固氮菌的数量。处理AN1氨化细菌数量,显著高于其他处理,BN2和AN2氨化细菌数量较少,有机肥和低浓度氮肥配施可提高土壤中氨化细菌数量,施用高浓度氮肥降低氨化细菌数量。施用有机肥可提高土壤中亚硝化细菌、反硝化细菌和纤维素分解菌的数量。反硝化细菌数量与全磷和速效磷含量显著相关,亚硝化细菌数量与碱解氮、速效钾和速效磷含量显著相关。纤维素分解菌与全氮、碱解氮、速效磷、有机质和速效钾含量显著相关。

Effect of Long-term Nitrogen Application on Culturable Microorganisms Quantity of Tomato Continuous Cropping

Based on the long-term fertilization experiment,the test studied the effect of the composition and quantity of soil microorganisms by selective medium methods,while measured soil nutrients and discussed the correlation with microbe.The results showed that the effect of different fertilizing methods on physiological groups of soil microorganism.Aerobic azotobacter amount of AN0 was the significantly higher than that of other treatments,AN1 and BN2 were significantly lower than other treatments.Organic manure increased aerobic azotobacter amount,but inorganic fertilizer could decrease the amount.The number of BN2 and AN2 were lower than that of others,and both had no significant differences with control.Organic manure in the combination of low level inorganic nitrogen fertilizer increased amount of ammonifying bacteria,while high level nitrogen fertilizer decreased the amount.Organic manure increased the number of nitrosobacteria,denitrifying bacteria,and cellulose-decomposing microorganisms.Denitrifying bacteria amount showed a significant correlation with total N and available P content,while nitrosobacteria amount showed a significant correlation with available N,available K and available P content.It was showed that the correlation cellulose-decomposing microorganisms amount with total N,available N,available P,O.M.,and available K content.