祁连山东缘高寒草甸灌丛化对植被群落与土壤理化特性的影响  

Effects of shrub encroachment of alpine meadows on vegetation community structure and soil physicochemical properties

作　　者：包段红 孙小妹[4] 张志明 王文碧 杨婷 王艳[1,2] 王静[5] 苏军虎[1,2,3] BAO Duanhong;SUN Xiaomei;ZHANG Zhiming;WANG Wenbi;YANG Ting;WANG Yan;WANG Jing;SU Junhu(College of Grassland Science,Key Laboratory of Grassland Ecosystem(Ministry of Education),Gansu Agricultural University,Lanzhou 730070,China;Gansu Agricultural University-Massey University Research Centre for Grassland Biodiversity,Gansu Agricultural University,Lanzhou 730070,China;Gansu Qilian Mountain Grassland Ecosystem Field Scientific Observatory,Wuwei 733000,China;College of Resource and Environmental Science,Gansu Agricultural University,Lanzhou 730070,China;Lanzhou Vocational and Technical College,Lanzhou 730070,China)

机构地区：[1]甘肃农业大学草业学院/草业生态系统教育部重点实验室,兰州730070 [2]甘肃农业大学-新西兰梅西大学草地生物多样性研究中心,兰州730070 [3]甘肃省祁连山草原生态系统野外科学观测研究站,武威733000 [4]甘肃农业大学资源与环境学院,兰州730070 [5]兰州职业技术学院,兰州730070

出　　处：《生态学报》2024年第14期6208-6218,共11页Acta Ecologica Sinica

基　　金：甘肃省自然科学基金(22JR5RA1057);中央引导地方科技发展资金项目(23ZYQH0298);武威市市级科技计划项目(WW2002YFS008)。

摘　　要：为明晰祁连山东缘高寒草甸灌丛化对其植被群落与土壤理化特性的影响,选取甘肃省天祝藏族自治县高寒草甸灌丛化区域,调查其植被,采集土壤测定理化性质,分析植被与土壤的互馈关系。结果表明:高寒草甸植被的均匀度指数、高度、盖度、地上生物量、土壤含水率随灌丛化过程增加(P<0.05),而多样性指数和容重均降低;全磷含量在各土层以灌丛区最高,但C∶P和N∶P以草甸区最高;土壤N∶P<14表明土壤养分主要受限于氮;土壤脲酶和过氧化氢酶活性在草甸区各土层显著高于灌丛区(P<0.05);冗余分析显示前两个排序轴的累计解释量为54.88%,土壤过氧化氢酶与植被特征拟合的结果最好(Pr=0.010),表明高寒草甸灌丛化过程中土壤过氧化氢酶受植被特征的制约最大。可见,高寒草甸灌丛化显著影响了植被群落结构与土壤理化特性,在祁连山生态保护和管理中应该予以重视。Shrub encroachment is an important ecological process that affects the nutrient cycle of alpine meadows.In order to investigate the impact of shrub encroachment on vegetation communities and soil physicochemical properties in alpine meadows along the eastern edge of the Qilian Mountains,this study focused on the shrub encroachment alpine meadow area of Tianzhu Tibetan Autonomous Region in Gansu Province.The study analyzed the characteristics of the vegetation in the meadow area,excessive area under the crown grass,bush in the excessive area,excessive area under the crown grass,bush in the scrub area,as well as the physical properties of the soils at depths of 0—10 cm,10—20 cm,and 20—30 cm.The study examined the nutrient content,stoichiometric ratios,the activities of urease,alkaline phosphatase,catalase,and sucrase activities.The results showed that the evenness index,height,cover and aboveground biomass of alpine meadow vegetation at the eastern edge of the Qilian Mountains increased significantly with the process of shrub encroachment.However,Simpson′s index,Shannon-Wiener′s index,and abundance index decreased.Soil water content in the 0—10 cm layer was significantly higher in the scrub area than in the meadow area.Additionally,the bulk density in the staggered area was significantly higher than that in the scrub area(P<0.05),and there was no significant change in pH.Soil nitrogen content in the 20—30 cm layer was significantly higher in the meadow area than in the staggered area,but C∶P soil total nitrogen content in the 20—30 cm layer was significantly higher in the meadow area than in the scrub area.Furthermore,the total phosphorus content in the 0—30 cm layer was significantly higher in the scrub area than in the meadow area(P<0.05),C∶P and N∶P were the highest in the meadow area,but the significance of soil organic matter content was not apparent.Soil N∶P<14 indicated that nitrogen was the main limiting factor for soil nutrients.The activities of soil urease and catalase were sign

关 键 词：高寒草甸 灌丛化 土壤酶活性 化学计量特征 植被特征 

分 类 号：Q948.113[生物学—植物学]