[Objective] The purpose of this paper was to investigate the effect of biochar and its interaction with root exudate nicotine on the physiological activity of root zone soil during tobacco cultivation. Field comparative experiments with different application amounts of biochar in Qixingguan Tobacco Station of Bijie Tobacco Company was set up. [Method] Based this experiment, different amounts of biochar, such as CK（0 kg 667 m-2 biochar）, T10（10 kg 667 m-2 biochar）, T20（20 kg 667 m-2 biochar）, T40（40 kg 667 m-2 biochar） and T80（80 kg 667 m-2 biochar）were applied in the farmland to investigate their influences on soil biological properties of flue-cured tobacco root zone. Ammonium nitrogen（NH4 +-N）, nitrate nitrogen（NO3--N）, hot water extracted organic nitrogen（HWON）,moderately stable organic N（6 M HCl hydrolyzed nitrogen, a-ON）, microbial biomass carbon（MBC）, microbial biomass nitrogen（MBN）, microbial hydrolysis activity（FDA activity）, soil basal respiration（SBR） and soil mineralizable N quantity（MinN） were determined by conventional methods. [Result]（1） The soil FDA activity was reduced in the biochar-amended soil. Compared to CK, the T40 and T80 treatments showed a significant decrease of33% ～ 55%, and there was no significant difference with other treatments. Overall, the greater the amount of biochar used, the greater the reduction in biological activity.（2） Compared to the CK treatment, soil basal respiration（SBR）was gradually enhanced with increasing biochar dosage and increased by about 33% in the T40 and T80 treatments.（3） For soil respiration, compared to adding only glucose, the soil respiration rate was lower after adding both glucose and nicotine, however, soil basal respiration remained the same for all treatments and was significantly lower than the CK treatment（P ＜ 0.05）.（4） Compared with the treatment of biochar alone, nicotine could stimulate the mineralization of soil N, but high amount of biochar（T80） could counteract the effect of nicotine. [Conclusion] Appropriate application of biochar may reduce the overall soil microbial activity in the root zone of tobacco plants and increase the basal respiration and nitrogen mineralization potential of the soil, while nicotine will reduce the glucose respiration and increase the mineralization potential of biochar-added soils, conversely. However, the effects of nicotine secreted by the root zone on the soil will be inhibited by hight levels of biochar. by biochar.

本文对各种混凝土(矿粉、粉煤灰、硅灰的掺入量为0、10％、20％、30％和40％,水胶比为0.3、0.32、0.38和0.42)进行电通量测试实验,结果表明:随着矿物掺和料的掺量增加,电通量值减小;不同掺和料的混凝土,电通量出现最大减幅时对应的掺量变化段不相同;当掺量达到30％之后,电通量变化幅度减少,趋于稳定;电通量随着水胶比增加而增加,抗氯离子渗透能力随之降低;掺矿粉的混凝土电通量最大,掺硅灰的电通量最小,但硅灰受水胶比的影响更大些.

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