不同中药渣组合好氧堆肥产物对土壤碳矿化特性的影响

Effects of Compost Products of Different Chinese Medicinal Residues on Soil Carbon Mineralization

为研究不同配方中药渣废弃物好氧堆肥产品品质差异及其对土壤碳素矿化的影响,设置了好氧堆肥和有机肥还田两个试验。通过工厂化条垛式好氧堆肥试验,研究了中药渣废弃物3种组合,在相同碳氮比、不同木质纤维素含量下对好氧堆肥产品品质的影响;采用土壤呼吸瓶进行室内恒温恒湿培养模拟土壤施肥效应,研究了3种有机肥施用对不同肥力土壤有机碳分解动态的影响。试验结果显示:中药渣物料的初始木质纤维素含量显著影响堆肥产品的碳氮养分转化和腐殖质组分。与初始低木质纤维素含量处理(T1)相比,高木质纤维素含量处理(T3)堆肥有机碳降解难,堆肥产品中全碳含量提高5.7%,全氮含量降低18.4%,但有利于腐殖质形成,尤其是显著增加胡敏酸组分20.9%。3种中药渣堆肥产品等碳量输入对不同肥力土壤的碳素矿化效果差异显著,高肥力土壤CO_(2)-C的释放速率和累积释放量均高于低肥力土壤,但有机碳的累积矿化率却低于低肥力土壤,并且高肥力土壤中添加T1堆肥产品累积矿化率显著高于添加T3堆肥产品。两个肥力土壤中有机肥中胡敏酸组分与土壤碳素矿化率之间呈显著负相关关系。因此,为提高有机肥的土壤固碳效应,可适当提高有机肥中胡敏酸组分,但不同肥力土壤应采用不同的养分管理策略。

In order to provide scientific basis and theoretical guidance for rational return to field of compost products,the quality difference of aerobic compost products from different formulations of Chinese medicinal residues and its influence on soil carbon mineralization were studied.The conducted experiment included two stages of aerobic composting and organic fertilizer return to the field.Through the factory strip aerobic composting experiment,the effects of three combinations of Chinese medicine residues on the quality of aerobic composting products at the same C/N ratio and different lignocellulose contents were studied,while soil breathing bottle was used for indoor culture under the constant temperature and humidity to simulate the effect of soil fertilization,and the effects of three kinds of organic fertilizers on the dynamic changes of organic carbon decomposition and soil organic carbon mineralization were studied under different fertility levels.The results show that lignocellulose content in the combinations of traditional Chinese medicine residues significantly affect carbon and nitrogen transformation and humus components of compost products.Compared with the initial low lignocellulose content treatment(T1),organic carbon is difficult to degrade under the high lignocellulose content treatment(T3),whose total carbon and nitrogen contents of the compost product is 5.7%higher and 18.4%lower than those of T1.And T3 is beneficial to the formation of humus,especially to humic acid component which is significantly increased by 20.9%compared with T1.The effects of three corresponding organic fertilizers on carbon mineralization are significantly different for different fertility soils under the same carbon input.The release rate and cumulative release amount of CO_(2)-C in high fertility soils are higher than those in low fertility soils,but the cumulative mineralization rate of organic carbon is lower than that in low fertility soils.In addition,the cumulative mineralization rate of T1 compost in high fertility soil is significantly higher than that of T3 compost.Humic acid component in organic fertilizer has a significant negative correlation with soil carbon mineralization,therefore,in order to improve soil carbon sequestration,humic acid components can be appropriately increased in organic fertilizers,however,different nutrient management strategies should be adopted for different fertility levels of soil.