秸秆生物炭对烤烟生长发育、土壤有机碳及酶活性的影响

摘要

为探讨秸秆生物炭在植烟土壤的应用效果，通过盆栽试验研究了不同生物炭添加量对烤烟生长发育、土壤有机碳及酶活性的影响。结果表明，土壤中添加适量生物炭（0.2%~1.0%）有助于烤烟的生长发育，表现为株高、叶面积及地上部茎、叶生物量的增加，而较高的添加量（5.0%）则有抑制作用；但烟株根系发育与此不同，其根系生物量与根冠比随生物炭添加量的增加而增加，其中以添加量5.0%时烤烟根系生物量及根冠比最高。此外，随生物炭添加量的增加，土壤有机碳及活性有机碳含量均呈增加趋势，但活性有机碳的增加效果没有总有机碳明显。土壤脲酶、蔗糖酶和酸性磷酸酶活性均随生物炭添加量的增加有不同程度提高，过氧化氢酶活性则下降或变化不大。因此，生物炭施用对烤烟生长发育及土壤生物活性具有重要影响，由于生物炭与土壤的相互作用是一个长期过程，后续还需通过长期定位试验来系统研究其对烟草生长发育的正负效应及其内在机理。%To investigate the effects of biochar application on tobacco field, pot experiments were conducted to study the impacts of straw biochar at different levels on tobacco growth, soil organic carbon and enzyme activities. The results showed that the growth of tobacco was promoted by biochar application in the soil at moderate levels (0.2%-1.0%). Tobacco height, tobacco leaf area, and the biomass of stem and leaves were all increased with moderate levels but inhibited by the high level (5.0%) of biochar application. Different from the aboveground organs, the growth of tobacco roots and the root/shoot ratio were both promoted with the tested levels of biochar application, with the 5.0% level of biochar treatment having the highest root biomass and root/shoot ratio. Moreover, the contents of soil organic carbon and active organic carbon both increased with the increase of biochar application, reaching the highest values in the 5.0% biochar treatment. The increase of active organic carbon was however less than that of total organic carbon. The soil urease, invertase and acid phosphatase activities all increased in different extent with the increase of biochar application, but the catalase activities were decreased or not changed. In summary, the effects of straw biochar application on tobacco growth and soil biological activities are very important, but the interaction between biochar and soil is a long-term process in tobacco field. Long-term experimental studies should be conducted to test the positive and negative effects of biochar application on tobacco growth and development and its related mechanisms.