长期不同施肥对棕壤细菌群落结构和碳代谢功能的影响  

Eeffects of Long-Term Fertilization on Bacterial Community Structure and Carbon Metabolic Functions in Brown Soil

作　　者：白雨欣 刘灵芝[1] 安婷婷[1] 李双异[1] 汪景宽[1] BAI YuXin;LIU LingZhi;AN TingTing;LI ShuangYi;WANG JingKuan(College of Land and Environment,Shenyang Agricultural University/National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources/Key Laboratory of Arable Land Conservation in Northeast China,Ministry of Agriculture and Rural Affairs,Shenyang 110866;Shenyang Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016;University of Chinese Academy of Sciences,Beijing 101400)

机构地区：[1]沈阳农业大学土地与环境学院/土肥资源高效利用国家工程实验室/农业农村部东北耕地保育重点实验室,沈阳110866 [2]中国科学院沈阳应用生态研究所,沈阳110016 [3]中国科学院大学,北京101400

出　　处：《中国农业科学》2025年第8期1579-1590,共12页Scientia Agricultura Sinica

基　　金：国家重点研发计划(2021YFD1500205);辽宁省高等学校基本科研项目(LJKMZ20220995)。

摘　　要：【目的】了解农田土壤细菌种群结构、关键物种以及细菌碳代谢功能与长期不同施肥土壤理化、生物学性质的关联性。【方法】基于细菌16S rRNA分子标记,采用扩增子测序技术,解析沈阳农业大学长期定位实验站29年连续实施不同施肥(不施肥,CK;单施化肥,N4;化肥减量配施有机肥,M2N2)后,土壤细菌群落结构、生态网络、潜在碳代谢功能与土壤理化生物学性质的关系。【结果】不同施肥处理导致土壤理化生物学性质以及细菌种群、多样性和潜在碳代谢基因丰度发生明显变化。与不施肥(CK)相比,长期单施化肥(N4)显著降低了土壤pH、细菌物种数量和群落多样性,化肥减量配施有机肥(M2N2)具有良好的维持作用。长期施肥(N4和M2N2)虽显著增加土壤呼吸作用,但明显降低0—20 cm土层土壤净氮矿化速率。其中,与N4处理相比,M2N2处理可明显提升土壤净氮矿化速率。土壤NH4+-N含量、净氮矿化速率和pH是土壤细菌种群差异的重要影响因子。网络共现分析显示,Bradyrhizobium elkanii和beta proteobacterium WWH154是维持细菌生态网络稳定性的关键物种,其中,100株优势细菌物种全部与beta proteobacterium WWH154呈共现关系,54%的物种与Bradyrhizobium elkanii表现出共现关系。长期施肥(N4和M2N2)可增加两个关键物种的相对丰度,增幅61.9%—169.4%,M2N2处理的增幅更为明显。碳代谢基因功能预测发现,N4处理降低土壤细菌碳固定、氨基酰基转运RNA生物合成和氨基酸相关酶等碳代谢基因的丰度,M2N2处理则能较好地稳定碳代谢途径。【结论】长期施肥改变农田土壤理化和生物学性质,化肥减量配施有机肥(M2N2)通过富集关键物种,增加微生物网络复杂性来响应环境变化,维持土壤生态功能,进而提升作物产量。【Objective】This study aimed to elucidate the relationships among bacterial population structure,key species,carbon metabolic functions,and variations in soil physicochemical and biological properties resulting from long-term different fertilization treatments in agricultural soils.【Method】The amplicon sequencing technology based on the molecular marker of bacterial 16S rRNA were employed to analyze soil bacterial community structure,ecological networks,potential carbon metabolic functions,and their correlations with soil physicochemical and biological properties after 29 years of continuous application of various fertilization treatments(no fertilization as control,CK;chemical fertilizers,N4;and reduced application of chemical fertilizer combined with organic manure,M2N2) at the Long-term Positioning Experimental Station at Shenyang Agricultural University.【Result】Different fertilization treatments significantly altered soil physicochemical and biological properties,and bacterial populations,diversity,and abundance of potential carbon metabolic genes.Compared with CK treatment,N4 treatment significantly decreased soil pH value,bacterial abundance and community diversity,which indicated that M2N2treatment demonstrated a beneficial maintenance effect.Although long-term fertilization practices(both N4 and M2N2)significantly increased soil respiration rates,they also markedly reduced net nitrogen(N) mineralization rates at 0-20 cm soil layer.Furthermore,compared with N4 treatment,M2N2 treatment significantly enhanced soil net N mineralization rates.Soil ammonium N content,net N mineralization rate and pH value were the critical environmental factors influencing soil bacterial populations.Network co-occurrence analysis revealed that Bradyrhizobium elkanii and beta proteobacterium WWH154 were the key bacterial species that maintained the stability of bacterial ecological networks,and about 100 dominant bacterial species co-occurred fully with beta proteobacterium WWH154 and 54% of the species co-occurred wi

关 键 词：长期施肥 棕壤 关键物种 细菌多样性 网络共现 

分 类 号：S154.3[农业科学—土壤学]