有机肥配施生物炭对果园土壤反硝化微生物和酶活性的影响  

Effects of Organic Fertilizer Combined with Biochar on Denitrifying Microorganisms and Enzyme Activities in Orchard Soil

作　　者：邓正昕 高明[1] 熊子怡 王蓥燕 谢军[1] 王子芳[1] DENG Zheng-xin;GAO Ming;XIONG Zi-yi;WANG Ying-yan;XIE Jun;WANG Zi-fang(College of Resources and Environment,Southwest University,Chongqing 400715,China)

机构地区：[1]西南大学资源环境学院,重庆400715

出　　处：《环境科学》2023年第12期6955-6964,共10页Environmental Science

基　　金：重庆市技术创新与应用示范专项重点研发项目(cstc2018jscx-mszdX0061);国家自然科学基金项目(42177019)。

摘　　要：为研究有机肥配施生物炭对土壤反硝化势和反硝化微生物群落结构的影响,以柠檬果园土壤为研究对象,采用盆栽试验,设置不施肥(CK)、常规施肥(F)、有机肥(P)、化肥+生物炭(FP)和有机肥+生物炭(PP)共5个施肥处理,通过实时荧光定量PCR技术和末端限制性片段长度多态性分析(T-RFLP)分别研究了反硝化微生物的丰度和群落结构;采用冗余分析(RDA)明确影响反硝化微生物群落结构的环境因子,运用PLS-PM分析揭示影响柠檬果园土壤反硝化势的环境因子.结果表明:(1)与单施化肥处理(F)相比,有机肥和生物炭(P、FP和PP)处理均显著提高了土壤反硝化势,提高范围为147.8%~1445.3%.有机肥配施生物炭处理较单施有机肥土壤反硝化势降低了23.8%.(2)与CK处理相比,施肥处理明显提高了nirS和nirK型反硝化微生物丰度;化肥处理(F和FP)显著降低nosZ型反硝化微生物丰度.施加生物炭的处理显著改变反硝化微生物的多样性和均匀度,但具体规律及机质尚不清晰.(3)RDA分析结果表明,施肥能通过改变C/N、WC、NO_(3)^(-)-N、SOC、AK和AP等土壤环境因子,从而影响土壤nirS、nirK和nosZ型反硝化微生物的群落结构.(4)PLS-PM结果分析表明,土壤反硝化势与pH和nirK型反硝化微生物丰度呈极显著正相关,NO_(3)^(-)-N通过影响nirK型反硝化微生物群落丰度间接影响土壤反硝化势.此外,nirK型反硝化微生物群落是柠檬果园土壤反硝化作用的主导菌群.综上,有机肥主要通过调控土壤pH直接影响土壤反硝化势,通过调控NO-3-N含量影响nirK反硝化微生物丰度间接影响土壤反硝化势,有机肥配施生物炭能减缓单施有机肥造成的土壤反硝化势提高的情况,更适合在该地区果园中进行推广.To study the effects of organic fertilizer combined with biochar on soil denitrification and denitrifying microbial community structure,this study took lemon orchard soil as the research object and adopted a pot experiment,setting up five fertilization treatments:no fertilization(CK),conventional fertilization(F),organic fertilizer(P),fertilizer+biochar(FP),and organic fertilizer+biochar(PP).The abundance and community structure of denitrifying microorganisms were studied using real-time quantitative PCR and T-RFLP.Redundancy analysis(RDA)was used to explore the environmental factors affecting the denitrifying microbial community structure,and PLS-PM analysis was used to explore the environmental factors affecting the denitrification potential of lemon orchard soil.The results showed as follows:①compared with that under the single fertilizer treatment(F),the organic fertilizer and biochar(P,FP,and PP)treatments significantly increased the denitrification potential of the soil,ranging from 147.8%to 1445.3%.The denitrification rate of soil treated with organic fertilizer combined with biochar was 23.8%lower than that treated with organic fertilizer alone.②Compared with that in the CK treatment,fertilization treatment significantly increased the abundance of nirS and nirK denitrification microorganisms.Fertilizer treatments(F and FP)significantly reduced the abundance of nosZ denitrifying microorganisms.Biochar treatment significantly changed the diversity and uniformity of denitrifying microorganisms,but the specific law and mechanism quality remained unclear.③The results of RDA analysis showed that fertilization could affect the community structure of nirS,nirK,and nosZ denitrifying microorganisms by changing C/N,WC,NO_(3)^(-)-N,SOC,AK,and AP.④PLS-PM analysis showed that soil denitrification was positively correlated with pH and the abundance of nirK denitrification microorganisms,and NO_(3)^(-)-N indirectly affected soil denitrification by affecting the abundance of nirK denitrification microorganisms.In

关 键 词：生物炭 有机肥 反硝化势 反硝化微生物 环境因子 

分 类 号：X172[环境科学与工程—环境科学]