植烟根际土壤生物活性对生物炭配施有机菌肥的响应

通过大田试验研究植烟土壤在生物炭与不同比例复方有机菌肥配施的条件下,烤烟根际土壤生物活性的动态变化,为植烟土壤的合理施用生物炭及有机菌肥提供理论依据。在施用等量烟草专用复合肥的基础上,设置CK(不施有机肥,烟农习惯施肥即仅施复合肥525 kg/hm2)、T1(增施生物炭1500 kg/hm2)、T2(增施复方有机菌肥1500 kg/hm2)、T3(增施60%复方有机菌肥+40%生物炭)、T4(增施50%复方有机菌肥 +40%生物炭)、T5(增施40%复方有机菌肥+60%生物炭)6个处理。结果表明,T2处理提高了整个生育期的土壤蔗糖酶活性,T2和T3处理显著提高了30 d的土壤脲酶活性,其酶活性分别为0.74 mg/(g.d)和0.75 mg/(g.d)。T2处理显著提高了30 d的土壤微生物量碳(达到810.09 mg/kg)和微生物碳熵,T3处理提高了整个生育期的微生物量氮和微生物氮熵；同时施用菌肥可明显提高土壤细菌、真菌和放线菌的数量,尤其T2处理的细菌和放线菌数量在整个生育期均最高。在豫中烟区,施用复方有机菌肥及60%复方有机菌肥配施40%生物炭对改善根际土壤微生物环境和土壤肥力效果最好。

Response of Tobacco Planting Rhizosphere Soil Biological Activities to Biochar Combined with Compound-organic-bacteria-fertilizer

The aim is to provide a basis for the reasonable application of biochar and compound-organicbacteria- fertilizer (COBF) in tobacco- planting soil. Based on the same amount of compound fertilizer application, six treatments were set up. Soil was sampled during the key tobacco growth stage (i.e. 30, 60, and 90 days after transplanted). The soil sample was analyzed for the effect of biochar and COBF on soil microorganisms’activities. The results showed that the sucrase activity in soil was significantly improved with T2 treatment in the whole growth period. The urease activity in soil under T2 and T3 treatments were significantly promoted attheearly growth stage (30d), and the urea seactivity was 0.74mg/(g·d)and0.75mg/(g·d), respectively. The microbial biomass carbon (SMBC, 810.09 mg/kg) and microbial biomass carbon entropy were improved under T2 treatment. The microbial biomass nitrogen (SMBN) and SMBN/TN were improved under T3 treatment during the whole tobacco growth period. The bacteria, fungi and actinomyce population were increased by COBF application. The highest population of bacteria and actinomyce appeared under T2 treatment during the whole tobacco growth period. Generally, in the central area of Henan Province, the application of COBBF and 60% COBBF combined with 40% biochar are the optimal practice to improve the soil microbial environment and fertility.