植物生态学报

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三江源地区高寒湿地土壤微生物生物量碳氮磷及其化学计量特征

聂秀青1,王冬2,周国英1,熊丰1,杜岩功1   

  1. 1. 中国科学院西北高原生物研究所
    2. 中国林业科学研究院林业研究所
  • 收稿日期:2021-03-26 修回日期:2021-08-18 发布日期:2021-08-26
  • 通讯作者: 王冬
  • 基金资助:
    林木培育重点实验室专项资金项目;第二次青藏科考项目;国家自然科学基金;国家重点研发项目;青海省自然科学基金;青海省国际交流合作项目

Microbial biomass carbon, nitrogen phosphorus and their stoichiometric characteristics in the Three Rivers Source Region alpine wetlands

Xiu-Qing NIE1,Dong Wang2,周 国英熊 丰1, 4   

  • Received:2021-03-26 Revised:2021-08-18 Published:2021-08-26
  • Contact: Dong Wang
  • Supported by:
    Key Laboratory of Tree Breeding and Cultivation Special fund Project;the Second Tibetan Plateau Scientific Expedition and Research Program;The National Natural Science Foundation of China;the National Key Research and Development Program of China;Qinghai Province International Exchange and Cooperation Project;the Natural Science Foundation of Qinghai

摘要: 微生物生物量及其化学计量特征是土壤养分循环的重要参数,对预测气候变化和提高模型准确性及其理解陆地生态系统养分循环都起到重要作用。目前,尚不清楚三江源地区高寒湿地土壤微生物生物量及其化学计量特征。为了明晰高寒生态系统土壤微生物生物量碳(MBC)、微生物生物量氮(MBN)、微生物生物量磷(MBP)及其化学计量特征,本研究通过在三江源区高寒湿地连续两年的野外调查和室内培养,分析了50个样点的数据,探究三江源高寒湿地MBC、MBN、MBP及其化学计量特征,明确了土壤理化特性和微生物群落特征对其影响。结果表明:(1) 三江源高寒湿地MBC、MBN和MBP分别为105.11、3.79和0.78 mmol kg-1,MBC: MBN、MBC: MBP、MBN: MBP和MBC: MBN: MBP分别为50.56、184.89、5.42和275: 5: 1。高寒湿地土壤的MBC显著地高于高寒草甸的MBC,而MBN和MBP在高寒湿地和高寒草甸之间没有显著性差异;高寒湿地土壤的MBC: MBN和MBC: MBP显著地高于高寒草甸,而MBN: MBP在高寒湿地和高寒草甸之间的差异不显著;(2) 土壤理化特性与MBC、MBN和MBP具有显著的相关性。土壤含水率与MBC: MBN和MBC: MBP之间存在显著的负相关关系,而土壤容重与MBC: MBN和MBC: MBP之间存在显著的正相关关系,土壤全氮含量和MBC: MBP之间存在显著的负相关关系,而与MBC: MBN之间的关系不显著。土壤理化特性对MBN: MBP的影响不显著;(3) 整体而言,微生物群落结构与MBC、MBN和MBP之间存在显著的相关性。微生物群落结构和MBC: MBN和MBC: MBP的关系是相似的,总磷脂脂肪酸(PLFA)、革兰氏阳性菌、革兰氏阴性菌、细菌、放线菌、丛枝菌根真菌和其他PLFA与MBC: MBN和MBC: MBP之间存在显著的负相关关系,而真菌:细菌与MBC: MBN和MBC: MBP之间存在显著的正相关关系,真菌与MBC: MBN和MBC: MBP之间的关系不显著。除丛枝菌根真菌外,MBN: MBP与微生物群落结构均无显著的相关关系。土壤理化性质和微生物群落结构与高寒湿地微生物生物量及其化学计量比之间呈显著的相关性,这将有助于更深入地理解高海拔地区的土壤养分循环。

关键词: 青藏高原, 高寒湿地, 微生物生物量, 化学计量特征, 微生物群落结构

Abstract: Aims Microbial biomass and their stoichiometric characteristics are not only significant parameters for soil nutrient cycles, but also can contribute to predicating climate changes, improving model accuracy, and deeply understanding terrestrial nutrient cycling. Our objective was to investigate microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), and microbial biomass phosphorus (MBP) and their stoichiometric characteristics of alpine wetlands in the Three Rivers Source Region. Methods Using data from 50 sites, we explored MBC, MBN, MBP, their stoichiometric ratio and their relationship with controlling factors of alpine wetlands across the Three Rivers Source Region. Important findings Our results showed that 1) MBC, MBN, MBP were 105.11, 3.79, 0.78 mmol kg-1, respectively, and MBC: MBN, MBC: MBP, MBN: MBP, MBC: MBN: MBP were 50.56, 184.89, 5.42, 275:5:1, respectively. 2) Soil physical and chemical properties could significantly affect MBC, MBN, and MBP. Soil moisture had significant negative effects on both MBC:MBN and MBC:MBP, while bulk density had positive effects on both MBC:MBN and MBC:MBP. Soil total nitrogen had negative relationship with MBC:MBP, while had weak effects on MBC:MBN. And soil physical and chemical properties also had weak effects on MBN:MBP. 3) Generally, soil microbial community had significant effects on MBC, MBN, and MBP. Soil microbial community had similar effects on both MBC:MBN and MBC:MBP. Total phospholipid fatty acid (PLFA), gram-positive bacteria, gram-negative bacteria, bacteria, actinomycete, arbuscular mycorrhizal fungi, and other PLFAs had negative effects on MBC:MBN and MBC:MBP, while fungi:bacteria had positive effects on both MBC:MBN and MBC:MBP, but fungi had weak relationship with both MBC:MBN and MBC:MBP. Except arbuscular mycorrhizal fungi, MBN:MBP had weak relationship with soil microbial community. Soil physical and chemical properties, and soil microbial community had significant effects on soil microbial biomass and their stoichiometric characteristic in Three Rivers Source Regions alpine wetlands, which are greatly helpful for deeply understanding terrestrial of high altitude nutrient cycling.

Key words: Qinghaizang Plateau, alpine wetlands, microbial biomass, stoichiometric characteristic, microbial community structure