摘要
全球气候变化导致积雪减少与氮沉降加剧,共同威胁北方生态系统。本研究以华北退化沙荒地为对象,通过积雪覆盖/除雪和施氮(50 kg·ha^(-1))/不施氮双因子野外控制试验(4处理×4重复),探究短期(1年)复合处理对土壤细菌群落结构、多样性及网络稳定性的影响。结果表明:施氮处理(CKN1)显著提高土壤硝态氮(P<0.05)和微生物生物量碳(MBC)含量(P<0.05),细菌群落Sobs指数显著增加13%;除雪处理(S0N0)显著降低MBC含量(P<0.01)。冗余分析(RDA)揭示硝态氮(NO_(3)^(-)-N)、铵态氮(NH_(4)^(+)-N)和速效钾(AK)是驱动群落结构变化的关键因子,其中Methylomirabilota和NB1-j相对丰度与NO_(3)^(-)-N显著正相关(P<0.01)。分子生态网络分析表明,施氮与除雪处理均提升了网络复杂性。综上,积雪减少与氮沉降通过调控关键环境因子协同影响土壤微生物群落结构与网络稳定性,本研究为沙荒地生态修复提供了科学依据。
Global climate change had reduced snowpack and increased nitrogen(N)deposition,jointly threatening northern ecosystems.In this study,we investigated the short-term(1-year)effects of snow cover/removal and N addition(50 kg·ha⁻¹)/no addition(two-factor field experiment,4 treatments×4 replicates)on soil bacterial community structure,diversity,and network stability in a degraded sandy wasteland in North China.The results showed that N addition(CKN1)significantly increased soil nitrate nitrogen(NO_(3)^(-)-N)(P<0.05),microbial biomass carbon(MBC)(P<0.05),and notably elevated the Sobs index of the bacterial community(P<0.01).Conversely,snow removal(S0N0)significantly decreased MBC(P<0.01).Redun dancy analysis(RDA)identified NO_(3)^(-)-N,ammonium nitrogen(NH_(4)^(+)-N),and available potassium(AK)as key drivers of community structural changes,with Methylomirabilota and NB1-j relative abundance showing significant positive correlations with NO_(3)^(-)-N(P<0.01).Molecular ecological network analysis revealed that both N addition and snow removal enhanced network complexity.Therefore,snow reduction and N deposition synergistically affect soil microbial community structure and network stability by regulating key environmental factors,providing a scientific basis for ecological restoration of sandy wastelands.
作者
徐恒康
付尧
陈超
庞卓
张国芳
张微微
逯辉
孙鑫博
阚海明
XU Heng-kang;FU Yao;CHEN Chao;PANG Zhuo;ZHANG Guo-fang;ZHANG Wei-wei;LU Hui;SUN Xin-bo;KAN Hai-ming(Institute of Grassland,Flower and Landscape Ecology,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China;College of Agronomy,Hebei Agricultural University,Baoding,Hebei Province 071000,China;College of Grassland,Xinjiang Agricultural University,Urumqi,Xinjiang 830052,China)
出处
《草地学报》
北大核心
2025年第12期3874-3884,共11页
Acta Agrestia Sinica
基金
北京市农林科学院青年科研基金项目(QNJJ202333)
北京市农林科学院科技创新能力建设专项(KJCX20230406,KJCX20230305,KJCX20230220,KJCX20240319)资助。
关键词
降雪变化
微生物多样性
土壤理化性质
土壤细菌群落结构
分子生态网络
Changes in snowfall
Microbial diversity
Soil physical and chemical properties
Soil bacterial community structure
Molecular ecological network
