摘要
以大兴安岭落叶松(Larix gmelini)林火灾后恢复中期的林地土壤为研究对象,利用高通量测序技术和磷脂脂肪酸法(PLFAs)测定和分析不同强度火烧过后土壤细菌和真菌的群落组成和多样性,采用随机森林回归模型和偏最小二乘结构方程模型筛选关键微生物物种并评估土壤理化性质对微生物的影响.结果表明:火灾后恢复中期过程中的土壤微生物量碳(MBC)和总氮(TN)显著高于未过火森林(P<0.05),而含水率(MC)和土壤速效钾(AK)含量显著降低(P<0.05);轻、中度火干扰的土壤细菌Shannon指数显著降低(P<0.05);轻、重度火干扰的土壤真菌Shannon指数显著升高(P<0.05);中度火干扰的土壤细菌生物量和微生物总生物量的含量均无显著差异(P>0.05);火灾后恢复中期土壤细菌优势菌门的相对丰度无显著变化(P>0.05),而真菌Basidiomycota相对丰度显著升高(P<0.05),Ascomycota显著降低(P<0.05);PCoA和PLS-SEM结果显示,土壤微生物的Beta多样性差异显著(P=0.001),火干扰作用显著改变了土壤有机碳(SOC)(-1.27)、AK(-0.91)和真菌组成(-0.68),MBC显著改变了细菌组成(0.29),SOC的含量显著改变了细菌组成(0.77),细菌生物量(0.86),细菌多样性(-0.98)和真菌组成(-0.68).研究发现,火烧过后的寒温带落叶松林土壤细菌和真菌通过中期年限的恢复后,其多样性、组成和生物量仍未恢复到未火烧时的状态,SOC是主要影响因素.
In this study,the soils of Larix gmelini forest after fire in the middle recovery period were selected as the research object.Illumina MiSeq technology and phospholipid fatty acid method(PLFAs)were used to determine and analyze the community composition and diversity of soil bacteria and fungi after different intensities of fire.Random forest regression model and partial least squares structural equation modeling were used to screen key microbial species and evaluate the effects of soil physicochemical properties on microorganisms.The results showed that soil microbial biomass carbon(MBC)and total nitrogen(TN)in the middle recovery period after fire were significantly higher than those in the unburned forest(P<0.05),while moisture content(MC)and soil available potassium(AK)content were significantly reduced(P<0.05);the Shannon index of soil bacteria in low and moderate fire disturbance was significantly reduced(P<0.05),the Shannon index of soil fungi in low and high fire disturbance was significantly increased(P<0.05),there was no significant difference in the content of soil bacterial biomass and total microbial biomass in moderate fire disturbance(P>0.05);the relative abundance of dominant bacterial phyla in soil bacteria in the middle recovery period after fire did not change significantly(P>0.05),the relative abundance of Basidiomycota increased significantly(P<0.05),while Ascomycota decreased significantly(P<0.05);PCoA and PLS-SEM results showed that the Beta diversity of soil microorganisms was significantly different(P=0.001).Fire disturbance significantly changed soil organic carbon(SOC)(-1.27),AK(-0.91)and fungal composition(-0.68),MBC significantly changed bacterial composition(0.29),and SOC content significantly changed bacterial composition(0.77),bacterial biomass(0.86),bacterial diversity(-0.98)and fungal composition(-0.68).The study found that after the fire,the diversity,composition and biomass of soil bacteria and fungi in the cold temperate Larix gmelini forest had not recovered to the state before the fire after the recovery of the mid-term,and SOC was the main influencing factor.
作者
程智超
杨立宾
付晓宇
逯昕明
刘思远
魏丹
CHENG Zhi-chao;YANGLi-bin;FU Xiao-yu;LU Xin-ming;LIU Si-yuan;WEI Dan(Institute of Natural Resources and Ecology,Heilongjiang Academy of Sciences,Harbin 150040,China)
出处
《中国环境科学》
北大核心
2025年第10期5836-5847,共12页
China Environmental Science
基金
国家林业草原生态保护恢复资金项目(GZCG2023-024)
黑龙江省省属科研院所科研业务费项目(CZKYF2023-1-B024)。
关键词
寒温带落叶松林
火灾后恢复中期
土壤微生物
群落结构
生物量
cold temperate Larix gmelini forest
mid term recovery after fire
soil microbial
community structure
biomass
