生物质炭引起的土壤碳激发效应与土壤理化特性的相关性  

Correlation Between Biochar-induced Carbon Priming Effect in Soils and Soil Physiochemical Properties

作　　者：刘本娟 谢祖彬[1] 刘琦 王晓洁 林志斌[1,2] 卑其成 蔺兴武[1] 刘钢[1] 朱建国[1] LIU Benjuan;XIE Zubin;LIU Qi;WANG Xiaojie;LIN Zhibin;BEI Qicheng;LIN Xingwu;LIU Gang;ZHU Jianguo(State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;University of Chinese Academy of Sciences,Beijing 100049,China;College of Forestry,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]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 [2]中国科学院大学,北京100049 [3]南京林业大学林学院,南京210037

出　　处：《土壤》2021年第2期343-353,共11页Soils

基　　金：国家自然科学基金项目(41171191,31870500);国家科技基础性工作专项(2015FY110700);公益性行业(农业)科研专项(201503137)资助。

摘　　要：生物质炭添加到土壤中将引发不同的激发效应,然而生物质炭激发效应与土壤性质之间的关系还不明确。将等碳量的13C稳定性同位素标记的小麦秸秆及其制成的生物质炭分别添加到4种不同性质的土壤中,室内培养1年,测定生物质炭及秸秆中碳元素在不同土壤中的降解量及其对土壤原有机碳的激发效应量。结果表明:生物质炭在黑土水稻土以及下位砂姜土水稻土中引发了显著的负激发效应,激发效应量分别为–284 mg/kg和–157 mg/kg,而在红壤水稻土以及低肥力红壤水稻土(长期定位不施肥的红壤水稻土)中引发正激发效应,激发效应量分别为33.3 mg/kg和58.0 mg/kg;秸秆在4种土壤中引发的激发效应量不同,均为正激发效应,正激发效应量远大于生物质炭。生物质炭激发效应量与土壤的EC(r=–0.884)以及pH(r=–0.824)呈极显著的负相关关系。生物质炭–碳在不同土壤上的累积降解量存在显著差异,黑土水稻土中为15.6 mg/kg,红壤水稻土中为14.2 mg/kg,下位砂姜土以及低肥力红壤水稻土中相似,分别为10.4 mg/kg和9.92 mg/kg;秸秆–碳的累积降解量远大于生物质炭–碳,其在低肥力红壤水稻土中的降解量显著低于其他3种土壤。生物质炭添加在黑土水稻土中碳净损失量最低,下位砂姜土水稻土中次之,低肥力红壤水稻土中最高。研究表明,生物质炭在土壤中的固碳效果不仅受到生物质炭–碳自身降解速率的影响,还会受到生物质炭引发的土壤碳激发效应量的影响。Biochar–induced priming effects were different between different soils,however the relationship between the priming effect and soil properties were still unclear.13C-labelled biochar pyrolyzed from 13C-labelled wheat straw was incorporated into 4 kinds of soils with contrasting properties for one-year incubation in lab,additionally,equivalent carbon amount 13C labelled wheat straw was also conducted.Results showed that biochar induced significant negative priming effects in Mollisol paddy soil and Inceptisol paddy soil,and the priming amount were–284 mg/kg and–157 mg/kg,respectively,but in Ultisol paddy soil and low fertility Untisol paddy soil(long-term experiment plot without fertility amendment),biochar induced positive priming effects with 33.3 mg/kg and 58.0 mg/kg priming amount respectively;Wheat straw induced different positive priming effects in soils,and the positive priming amounts were higher than those of the biochar-induced.Biochar-induced priming effect was significantly negatively correlated with soil EC(r=–0.884)and soil pH(r=–0.824).After one-year incubation,and the cumulative biochar-carbon decomposition were 15.6 mg/kg in Mollisol paddy soil,14.2 mg/kg in Untisol paddy soil,10.4 mg/kg in Inceptisol paddy soil and 9.92 mg/kg in low fertility Untisol paddy soil;Straw-carbon cumulative decomposition was much higher than biochar-carbon,and it was the lowest in low fertility paddy soil than in other three soils.The calculated carbon net loss was the lowest in Mollisol paddy soil following by Inceptisol paddy soil,and low fertility Ultisol paddy soil was the highest.The study indicates that carbon sequestration effect of biochar is influenced not only by decomposition of biochar-carbon itself,but also by biochar-induced priming effect.

关 键 词：生物质炭 激发效应 土壤性质 稳定性同位素标记 固碳效果 

分 类 号：S154.2[农业科学—土壤学]