摘要
岩溶区黄龙病柑橘园土壤氮转化存在特殊性。土壤改良剂生物炭对岩溶区黄龙病柑橘园土壤N_(2)O排放的影响及其微生物调节途径目前尚不清楚。本文通过室内培育试验研究了生物炭添加对岩溶区黄龙病脐橙园土壤N_(2)O排放、土壤氮素净硝化率/矿化率、硝化和反硝化功能基因的影响及其相互关系。结果表明,添加生物炭改变了土壤氮素净硝化率/矿化率、反硝化相关功能基因nosZ和硝化相关功能基因AOA-amoA、AOB-amoA的丰度,添加量为2%时是多数指标增长的峰值,与对照差异显著。添加生物炭降低了岩溶区脐橙园土壤N2O的平均排放速率和累积排放量,但各处理间差异不显著。DCA排序显示生物炭添加不同处理N_(2)O的排放速率主要受NH_(4)^(+)-N含量、nirK丰度、nosZ丰度的负向影响,NO_(3)^(–)-N含量和AOA-amoA丰度的正向影响。若要进一步提升生物炭对该土壤的减排效果,应注意提升土壤NH_(4)^(+)-N水平和反硝化相关功能基因丰度,抑制土壤NO_(3)^(–)-N水平和硝化相关功能基因AOA-amoA的丰度。本研究结果可为岩溶区黄龙病柑橘园土壤N_(2)O减排及调节机制研究提供借鉴。
Soil nitrogen transformation of the Huanglongbing citrus orchard in the karst area has a particularity.The effects of soil amendment biochar on soil N_(2)O emissions from the Huanglongbing citrus orchards in the karst areas and the microbial regulation pathways are currently unclear.In this study,the effects of biochar addition on soil N_(2)O emissions,soil nitrogen net nitrification rates/mineralization rates,nitrification,and denitrification functional gene expression and their relationships were analyzed through cultivation experiments.The results showed that the addition of biochar altered the net nitrification rates/mineralization rates of soil nitrogen,abundance of denitrification-related functional genes nosZ,and nitrification-related functional genes AOA-amoA and AOB-amoA.When 2%biochar was added,it was the peak of most indicators,which was significantly different from the control.The addition of biochar reduced the average emission rates and cumulative emissions of N_(2)O from the soil of the navel orange orchard in the karst area,but the differences among treatments were not significant.The DCA ordination test results showed that the N_(2)O emission rates of different biochar addition treatments were mainly affected by the negative effects of NH_(4)^(+)-N content,nirK abundance,and nosZ abundance and the positive effects of NO_(3)^(–)-N content and AOA-amoA abundance.To improve the effects of biochar on reducing soil N_(2)O in the future,attention should be paid to increasing soil NH_(4)^(+)-N levels and the abundance of denitrification-related functional genes,while suppressing soil NO_(3)^(–)-N levels and the abundance of nitrification-related functional genes,AOA-amoA.The results of this study provide a reference and support for tion-related functional genes,AOA-amoA.The results of this study provide a reference and support for the study of soil N_(2)O emission reduction and mainatinence of the Huanglong citrus orchards in karst areas.
作者
岳鹏鹏
付灿
江晓雨
王蓉
黄雅丹
YUE Peng-peng;FU Can;JIANG Xiao-yu;WANG Rong;HUANG Ya-dan(School of Intelligent Medicine and Biotechnology,Guilin Medical University,Guilin,Guangxi 541199;Graduate School of Guilin Medical University,Guilin,Guangxi 541199)
出处
《地球学报》
CAS
CSCD
北大核心
2022年第4期502-508,共7页
Acta Geoscientica Sinica
基金
广西自然科学基金项目(编号:2018JJB150056)
广西科技基地和人才专项(编号:2020AC20045)联合资助。
作者简介
第一作者:岳鹏鹏,女,1981年生。博士,副教授。研究方向为全球变化生态学与微生物生态学。E-mail:yue_pengpeng@163.com。;通讯作者:黄雅丹,女,1980年生。硕士,助理研究员。主要从事微生物生态学研究。E-mail:2376393446@163.com。