高原鼠兔和刈割扰动对高寒草甸植物群落和土壤特征的影响  

Effects of plateau pika and mowing disturbances on plant community and soil physical and chemical properties in alpine meadow

作　　者：苏晓雪 李希来[1] 孙华方 宋梓涵 李杰霞 张静[1] SU Xiaoxue;LI Xilai;SUN Huafang;SONG Zihan;LI Jiexia;ZHANG Jing(College of Agriculture and Animal Husbandry,Qinghai University,Xining 810016,China;College of Ecological Environment and Resources,Qinghai Minzu University,Xining 810007,China;Key Laboratory of Adaptation and Evolution of Plateau Biota,Northwest Institute of Plateau Biology,Chinese Academy of Sciences,Xining 810008,China)

机构地区：[1]青海大学农牧学院,西宁810016 [2]青海民族大学生态环境与资源学院,西宁810007 [3]中国科学院西北高原生物研究所高原生物适应与进化重点实验室,西宁810008

出　　处：《生态学报》2024年第22期10189-10199,共11页Acta Ecologica Sinica

基　　金：青海省科学技术厅科技援青合作专项项目(2023-QY-210);国家自然科学联合基金项目(U21A20191);青海大学青年教师科研基金项目(2021-QNY-12);高等学校学科创新引智计划项目(D18013)。

摘　　要：受过度放牧和高原鼠兔暴发的双重扰动影响,青藏高原高寒草甸植物群落和土壤特征发生显著变化。以青海省河南蒙古族自治县克其河滩高寒草甸为研究对象,通过连续5年的控制试验,分析不同刈割强度和高原鼠兔密度处理对高寒草甸植被群落和土壤性质的影响。研究结果表明:(1)刈割和高原鼠兔两种处理干扰及交互作用显著影响植被高度和盖度(P<0.05),随着年份的增加,植被群落盖度显著下降;不同年份间植被盖度,地上生物量,禾本科、莎草科、豆科、杂类草功能群重要值,植被群落Simpson指数、Shannon⁃Wiener指数、物种均匀度指数和物种丰富度指数存在显著差异(P<0.05)。(2)随着年份与刈割强度的增加,土壤全氮、全磷表现为先增加后减少的趋势。年份、刈割强度及其之间的交互作用对土壤温度有显著影响(P<0.05),重度刈割处理使得土壤温度显著提高(P<0.05)。不同刈割强度和鼠兔密度影响下年份、刈割强度及其交互作用对草地全氮和全磷有极显著影响(P<0.01)。高原鼠兔数量的增加显著降低了土壤pH,高密度干扰下较无鼠兔干扰pH下降了0.23,鼠兔密度对土壤全氮和全磷含量没有显著影响。中度刈割有利于退化高寒草甸植被和土壤的恢复,因此,通过控制放牧强度和高原鼠兔密度,正确识别草地放牧强度和鼠兔种群密度生态阈值,进行草地的合理管控,有利于草地畜牧业的持续高质量发展。Plant community and soil characteristics of alpine meadow could be obviously changed by both overgrazing and plateau pika outbreaks.This paper takes alpine meadow in Keqihetan,Henan Mongolian Autonomous County,Qinghai province as an example to study pika disturbance and mowing effects on plant community and soil physical and chemical properties in alpine meadow through a five⁃year controlled experiment.Mowing intensity and pika density are taken as two disturbance factors on vegetation community and soil in alpine meadow.The study results show that:(1)Mowing intensity,pika density and their interaction obviously interfere with vegetation height and coverage(P<0.05).During the 5⁃year experimental period,the coverage of vegetation community decreased significantly.There are significant differences in vegetation coverage,aboveground biomass,importance values of the functional groups of Gramineae,Cyperaceae,Leguminosae and Forbs,Simpson index,Shannon⁃Wiener index,species evenness index and species richness index of vegetation communities among different years(P<0.05).(2)Total nitrogen and phosphorus raise as time and mowing density increase,then they both decline.Duration,mowing intensity,and their interaction has significant effects on soil temperature(P<0.05),and heavy mowing treatment increase soil temperature(P<0.05)significantly.Pika density,duration,mowing intensity,and their interaction has significant effects on total nitrogen and phosphorus(P<0.01).Plateau pika density increase brings a significant decrease in soil pH,and the pH decreases by 0.23 under high density treatment compared with no pika treatment.Meanwhile pika density has no significant effects on soil total nitrogen and phosphorus content.Therefore,moderate mowing is conducive to the restoration of the degraded alpine meadow vegetation and soil.In addition,identifying and setting the ecological thresholds of grazing intensity and plateau pika density in the degraded alpine meadow are critical to achieve sustainable and high⁃quality develo

关 键 词：高寒草甸 刈割 高原鼠兔 干扰 植物群落 土壤特征 

分 类 号：S812[农业科学—草业科学]