| 高寒沼泽草甸土壤微生物残体碳与微生物群落结构对增温与氮添加的响应 |
| 摘要点击 1412 全文点击 11 投稿时间:2025-08-18 修订日期:2025-10-30 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 高寒沼泽草甸 微生物残体碳(MNC) 氨基糖 酶活性 土壤微生物 |
| 英文关键词 alpine swamp meadow microbial necromass carbon (MNC) amino sugars enzyme activity soil microorganisms |
| DOI 10.13227/j.hjkx.202508165 |
| 作者 | 单位 | E-mail | | 白炜 | 兰州交通大学环境与市政工程学院, 兰州 730070 寒旱地区水资源综合利用教育部工程研究中心, 兰州 730070 | baiwei915@163.com | | 马若冰 | 兰州交通大学环境与市政工程学院, 兰州 730070 寒旱地区水资源综合利用教育部工程研究中心, 兰州 730070 | | | 陈梦佳 | 兰州交通大学环境与市政工程学院, 兰州 730070 寒旱地区水资源综合利用教育部工程研究中心, 兰州 730070 | | | 杨宜轩 | 兰州交通大学环境与市政工程学院, 兰州 730070 寒旱地区水资源综合利用教育部工程研究中心, 兰州 730070 | | | 王春雨 | 兰州交通大学环境与市政工程学院, 兰州 730070 寒旱地区水资源综合利用教育部工程研究中心, 兰州 730070 | | | 王一博 | 兰州大学资源环境学院, 兰州 730000 | |
|
| 中文摘要 |
| 气候变化,尤其是气温升高和大气氮沉降增加,已成为影响陆地生态系统碳循环的重要因素. 为探究高寒生态系统土壤微生物残体碳组分对土壤有机碳库的贡献及其影响因素,在青藏高原典型高寒沼泽草甸,设置增温、施氮、增温同时施氮和对照4种处理开展原位试验,分析了土壤真菌残体碳(FNC)和细菌残体碳(BNC)的变化特征及影响因子. 结果表明,增温导致FNC和FNC/SOC显著增加了23.20%和26.76%(P<0.05),施氮、增温同时施氮导致FNC分别显著下降61.86%、50.86%(P<0.05),FNC/SOC分别下降了15.81%和19.05%(P<0.05);BNC/SOC在施氮、增温同时施氮下明显被促进,分别显著增加了92.24%和73.58%(P<0.05);Mantel检验分析发现,真菌门类中子囊菌门、毛霉门、担子菌门、捕虫霉门与FNC呈显著相关,细菌门类中酸杆菌门、棒状杆菌门与FNC呈显著相关;相关性分析及PLS-PM分析表明,土壤养分特征在对微生物残体碳的影响中起主导作用,其中土壤有机碳、总磷和有机磷与微生物残体碳(MNC)呈显著正相关,而总氮、硝态氮则与其呈显著负相关;酶活性与 α多样性中,N-乙酰-β-D-葡萄糖苷酶、过氧化物酶、真菌Simpson指数、细菌Chaol指数与MNC呈显著正相关,而脲酶则与其呈显著负相关. 由上述结果可见,在高寒沼泽草甸生态系统,增温和施氮对土壤微生物残体碳的积累表现出相反的效应,且土壤养分特征是介导这一过程的关键因素. |
| 英文摘要 |
| Climate change, especially global warming and increasing atmospheric nitrogen (N) deposition, has become a major driver of carbon cycle in terrestrial ecosystems. To the role of microbial residues in soil organic carbon (SOC) accumulation and identify their controlling factors under climate change scenarios, a field experiment was conducted in an alpine swamp meadow on the Qinghai-Tibet Plateau. The experiment included four treatments: control group, warming, N addition, and combined warming with N addition. Soil microbial necromass carbon (MNC) was quantified by separately assessing fungal necromass carbon (FNC) and bacterial necromass carbon (BNC) using amino sugar biomarkers. Warming significantly increased FNC and FNC/SOC by 23.20% and 26.76%, respectively (P<0.05). In contrast, N addition and the combined treatment significantly decreased FNC by 61.86% and 50.86% (P<0.05) and decreased FNC/SOC by 15.81% and 19.05% (P<0.05). N addition and the combined warming with N addition significantly promoted the BNC/SOC by 92.24% and 73.58%, respectively (P<0.05). Mantel tests indicated significant correlations between FNC and dominant fungal phyla such as Ascomycota, Mucoromycota, Basidiomycota, and Zoopagomycota, and bacterial phyla including Acidobacteriota and Rokubacteria. Correlation analysis and PLS-PM revealed that soil nutrient properties were the primary factors influencing MNC. Specifically, SOC, total phosphorus (TP), and organic phosphorus (O-P) were significantly and positively correlated with MNC, while total nitrogen (TN) and nitrate nitrogen (NO3--N) were negatively correlated with it. Regarding soil enzymatic activities and microbial diversity indices, N-acetyl-β-D-glucosaminidase (NAG) activity, peroxidase (POD) activity, the fungal Simpson diversity index, and the bacterial Chao1 richness index positively correlated with MNC. Conversely, urease (URE) activity showed a significant negative correlation with MNC. These findings highlight divergent responses of MNC to climate warming and N deposition, driven primarily by soil nutrient properties. This study provides evidence for understanding the carbon stabilization mechanisms in cold region ecosystems under future climate change scenarios. |