生物炭及秸秆对水稻土各密度组分有机碳及微生物的影响  

Effects of biochar and straw on both the organic carbon in different density fractions and the microbial biomass in paddy soil

作　　者：韩玮[1] 申双和[1] 谢祖彬[2] 李博[1] 李玉婷[1] 刘琦[2] 

机构地区：[1]气象灾害预报预警与评估协同创新中心,江苏省农业气象重点实验室,南京信息工程大学,南京210044 [2]土壤与农业可持续发展国家重点实验室,中国科学院南京土壤研究所,南京210008

出　　处：《生态学报》2016年第18期5838-5846,共9页Acta Ecologica Sinica

基　　金：土壤与农业可持续发展国家重点实验室开放课题(Y212000016);江苏省高校自然科学研究面上项目(14KJB170013);江苏省农业气象重点实验室开放基金(JKLAM201205)

摘　　要：生物炭被认为是土壤碳封存的有效手段,但是关于生物炭对土壤不同密度组分有机碳影响的研究报道很少。以南方稻麦轮作区水稻土为研究对象,通过田间小区试验研究了不施有机物(CK)、玉米秸秆还田(CS)、施用300℃热解生物炭(300BC)、施用400℃热解生物炭(400BC)和施用500℃热解生物炭(500BC)处理对土壤轻重组分质量比例,土壤轻重组分有机碳和土壤微生物的影响。结果表明:1)施用生物炭显著提高了土壤轻组的质量比例和土壤轻组有机碳含量,轻组有机碳含量为500BC>400BC>300BC>CS>CK,对重组有机碳影响不显著,但重组有机碳在土壤中占重要比例;2)施加生物炭后土壤微生物量相比对照也有提高,但是与施加秸秆处理相比,微生物量提高幅度较小。研究表明,生物炭能提高土壤有机碳含量,尤其提高了土壤轻组有机碳的累积,但由于生物炭特殊的芳烃结构,其轻组组分化学性质稳定,这与传统的土壤有机碳轻组理论不同。与秸秆处理相比,生物炭处理具有较低的土壤微生物量与微生物商,有利于土壤碳的固定。The loss of soil organic matter is a major concern in many areas of the world, especially in China, in rice paddies under warm-humid climatic conditions. Because carbon content is typically associated with soil quality, there is a need to preserve soil carbon pools. Biochar is a material that has shown promise as a means of soil amendment and carbon sequestration. However, it is unclear how the added biochar affects the distribution of organic carbon among different density fractions. In the current study, a field experiment was conducted to study the effects of biochar application on the organic carbon distribution among different density fractions and the soil microbial biomass of paddy soil. The five treatments were soil only （CK）, soil and corn straw （CS）, soil and biochar produced at 300℃ （300BC）, soil and biochar produced at 400℃ （400BC）, and soil and biochar produced at 500℃ （500BC）. The different biochars were added to the field twice, at a concentration of 6 t/hm2. The results show that biochar application increased the size of the light fraction proportion significantly, by 39.81%-41.20% compared to the CK treatment. This may be because of the low density of biochar. The added biochar increased the organic carbon content of the light fraction （LFOC） significantly, by 60.04%-69.66% compared to the CK treatment. LFOC in the different treatments was ordered as follows：500BC 〉 400BC 〉 300BC 〉 CS 〉 CK. The organic carbon content was highest in the 500BC treatment, with a value of 185.1 g/kg. This may be due to the higher carbon content of biochar produced at higher temperatures. With the increase in pyrolysis temperature, the volatile matter content decreased, the organic carbon content increased, and the stability of the organic carbon increased. Additionally, compared to the control, corn straw application also increased the organic carbon content. The organic carbon content was significantly lower in the straw amendment treatment than in the biochar treatments. None

关 键 词：生物炭 土壤有机碳 轻组有机碳 微生物生物量 

分 类 号：S153.6[农业科学—土壤学] S154.3[农业科学—农业基础科学]