贺兰山不同海拔优势植物细根-根际土壤生态化学计量特征  

Ecological stoichiometric characteristics of the fine roots and rhizosphere soil of dominant plants at different altitudes in the Helan Mountains

作　　者：张硕 郭艳菊 邱开阳[1,2,3,4] ZHANG Shuo;GUO Yanju;QIU Kaiyang(School of Forestry and Prataculture,Ningxia University,Yinchuan 750021,Ningxia,China;Ningxia Grassland and Animal Husbandry Engineering Technology Research Center,Yinchuan 750021,Ningxia,China;Key Laboratory for Model Innovation in Forage Production Efficiency,Ministry of Agriculture and Rural Affairs,P.R.China,Ningxia University,Yinchuan 750021,Ningxia,China;Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwestern China,Ningxia University,Yinchuan 750021,Ningxia,China)

机构地区：[1]宁夏大学林业与草业学院,宁夏银川750021 [2]宁夏草牧业工程技术研究中心,宁夏银川750021 [3]宁夏大学农业农村部饲草高效生产模式创新重点实验室,宁夏银川750021 [4]宁夏大学西北土地退化与生态恢复国家重点实验室培育基地,宁夏银川750021

出　　处：《草业科学》2025年第2期316-328,共13页Pratacultural Science

基　　金：宁夏自然科学基金优秀青年项目(2022AAC05007);宁夏大学卓越农林本科人才培养卓越教学团队(新农科)项目(ZYJXTD2023003);宁夏大学大学生创新创业训练计划项目(202410749569)。

摘　　要：为探究优势植物细根−根际土壤碳(C)、氮(N)和磷(P)含量及其生态化学计量比沿海拔梯度的变化特征及其相互关系,于2023年8月-9月,以贺兰山沿海拔梯度选取的5个典型植被类型(荒漠草原、浅山灌丛、常绿针叶林、亚高山灌丛草甸和高山灌丛草甸)为研究对象,分别采集优势植物细根及根际土壤,并测定其C、N和P含量。结果表明:1)优势植物细根全碳、C꞉N与根际土壤C꞉P、N꞉P均随海拔上升呈增加趋势,而根际土壤全磷呈相反的变化趋势;不同海拔优势植物细根全氮、全磷和根际土壤C꞉N随海拔升高呈现先升高后降低的趋势,呈倒“V”型分布,最大值均出现在常绿针叶林,与优势植物细根C꞉P的变化趋势相反。2)不同海拔优势植物细根全碳与根际土壤有机碳(P=0.041)、全氮(P=0.016)、根际土壤C꞉P(P=0.013)、N꞉P(P=0.007)均呈显著正相关关系。高海拔(亚高山灌丛草甸和高山灌丛草甸)较低海拔(荒漠草原和浅山灌丛)出现了根际土壤磷限制。本研究结果可为山地生态系统的生态恢复与长期发展提供科学依据。In order to determine the variation characteristics and correlation of carbon(C),nitrogen(N),and phosphorus(P)contents in dominant plant fine roots and rhizosphere soil,as well as their ecological stoichiometric ratios,along an altitudinal gradient,we assessed five typical vegetation types(desert steppe,low mountain shrubland,evergreen coniferous forest,subalpine shrub meadow,and alpine shrub meadow)in the Helan Mountains from August to September 2023.We collected the fine roots of dominant plants and rhizosphere soil and determined their C,N,and P contents.The results revealed the total C in dominant plant fine roots and the C꞉N ratio increased with altitude,whereas the C꞉P and N꞉P ratios in rhizosphere soil showed an opposite trend.Comparatively,the total N and total P contents in dominant plant fine roots and the C꞉N ratio in rhizosphere soil showed an initial increase followed by a subsequent decline with increasing altitude,characterized by an inverted“V”distribution,with the maximum values being recorded in the evergreen coniferous forest,which was opposite to the trend observed for the C꞉P ratio in the dominant plant fine roots.In addition,we detected significant positive correlations between total C in the dominant plant fine roots and the organic C(P=0.041),total N(P=0.016),C꞉P ratio(P=0.013),and N꞉P ratio(P=0.007)in rhizosphere soil at different altitudes.Compared with lower altitudes(desert steppe and low mountain shrubland),we observed P limitation in the rhizosphere soil at higher altitudes(subalpine shrub meadow and alpine shrub meadow).The findings of this study will provide a scientific basis for the ecological restoration and long-term development of mountain ecosystems.

关 键 词：贺兰山 生态化学计量比 细根 海拔梯度 根际土壤 

分 类 号：Q948.1[生物学—植物学]