摘要
稳定性是生物炭发挥固碳功能的基础,探究生物炭在土壤中的降解特征具有重要的现实意义。以水稻秸秆为生物质原料,在不同炭化温度和蛭石改性条件下制得一系列生物炭,探索其稳定性变化规律,并通过实验室恒温培养试验,研究了蛭石改性和未改性水稻秸秆生物炭在红壤、水稻土中的短期降解行为及其影响因素。水稻秸秆生物炭的碳含量随炭化温度的升高而增加,经蛭石改性后降低了20.3%~32.6%。当炭化温度从300℃升高至700℃时,生物炭的可溶性有机碳(DOC)含量表现为先增后减的变化趋势,在400℃时为最大值,700℃时为最小值。蛭石改性降低了所有生物炭的DOC含量。生物炭的H/C随炭化温度升高而降低,且经蛭石改性后有所降低。与300℃生物炭相比,700℃未改性和蛭石改性生物炭的热损失量分别降低了56.1%和56.8%。蛭石改性使生物炭的热损失量降低14.8%~45.6%。水稻秸秆生物炭的含碳官能团主要由芳香碳、烷氧碳与非取代脂肪烃组成,其中芳香碳含量最高;随着炭化温度的升高,生物炭中的芳香碳含量增加,烷氧碳与非取代脂肪烃含量下降;蛭石改性增加了生物炭中的芳香碳含量。与红壤相比,水稻土中生物炭的碳含量更低;与淹水条件相比,干旱条件下土壤中生物炭的碳含量更低。结果表明,蛭石改性在降低生物炭中碳含量的同时增加了生物炭的稳定性。相比于红壤,生物炭在水稻土中的碳降解速度更快;相比于淹水条件,干旱条件下生物炭的碳降解速度更快。综合来看,蛭石改性为显著影响生物炭在土壤中发生碳素降解的最主要因素,其次为土壤类型,水分状况的影响相对较弱。
Stability is the basic premise for biochar use as a mode of carbon sequestration.It is of great practical significance to explore the degradation characteristics of biochar in soils.In this study,rice straw and vermiculite were chosen as the biomass and mineral modification material to produce biochar,and the stability of the produced biochar was analyzed.Lab incubation experiments were carried out to study the short-term degradation behavior of biochar and its influencing factors.Results showed that the C content of biochar increases with an increase in carbonization temperature.After vermiculite modification,the C content of biochar reduced by 20.3%~32.6%.When the carbonization temperature increased from 300℃to 700℃,the dissolved organic carbon(DOC)of biochar first increased and then decreased,with the maximum value at 400℃and the minimum value at 700℃.Vermiculite modification reduced the DOC content of all biochar.With an increase in carbonization temperature,the H/C of biochar decreased.The H/C of modified biochar was lower than that of unmodified biochar.Compared with 300℃biochar,the thermal mass loss of 700℃unmodified and modified biochar decreased by 56.1%and 56.8%,respectively.Vermiculite modification reduced the thermal mass loss by 14.8%~45.6%.All biochar was mainly composed of aromatic C,O-alkyl C,and alkyl C,among which the content of aromatic C was the highest.With an increase in carbonization temperature,the aromatic C content in biochar increased,while the O-alkyl C and alkyl C contents decreased.Vermiculite modification increased the content of aromatic C.Compared with red soil,the C content of biochar in paddy soil was lower.Compared with flooding conditions,the C content of biochar under drought conditions was lower.These results indicate that vermiculite modification reduces the content of C in biochar and increases the stability of biochar.Compared with red soil,the C degradation of biochar in paddy soil is faster.Compared with flooded conditions,the C degradation of biochar under dry conditions is faster.Vermiculite modification is the primary factor affecting the degradation of biochar in the soil,followed by soil type and water condition.
作者
王瑞
刘玉学
高诚祥
何莉莉
汪玉瑛
吕豪豪
杨生茂
梁宗锁
WANG Rui;LIU Yuxue;GAO Chengxiang;HE Lili;WANG Yuying;LÜHaohao;YANG Shengmao;LIANG Zongsuo(College of Life Sciences and Medicine,Zhejiang Sci-Tech University,Hangzhou 310018,China;Institute of Environment,Resource,Soil and Fertilizer,Zhejiang Academy of Agricultural Sciences,Hangzhou 310021,China;Engineering Research Center of Biochar of Zhejiang Province,Hangzhou 310021,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2021年第9期1954-1962,共9页
Journal of Agro-Environment Science
基金
国家自然科学基金项目(41701334,42077090)
浙江省自然科学基金项目(LY20D010005)。
关键词
生物炭
改性
稳定性
土壤
固碳
biochar
modification
stability
soil
carbon sequestration
