1、第 32 卷 第 6 期Vol.32,No.6157-1662023 年 6 月草业学报ACTA PRATACULTURAE SINICA刘彩凤,段媛媛,王玲玲,等.高原鼠兔干扰对高寒草甸植物物种多样性与土壤生态化学计量比间关系的影响.草业学报,2023,32(6):157166.LIU Cai-feng,DUAN Yuan-yuan,WANG Ling-ling,et al.Effects of plateau pika(Ochotona curzoniae)disturbance on the relationship between plant species diversity and
2、 soil ecological stoichiometry in alpine meadows.Acta Prataculturae Sinica,2023,32(6):157166.高原鼠兔干扰对高寒草甸植物物种多样性与土壤生态化学计量比间关系的影响刘彩凤,段媛媛,王玲玲,王乙茉,郭正刚*(兰州大学草地农业教育部工程研究中心,兰州大学草地农业科技学院,甘肃 兰州 730020)摘要:植物物种多样性和土壤生态化学计量比间的关系,是草地植物群落结构维持的关键。高原鼠兔干扰虽被证实能够影响植物物种多样性、土壤有机碳、全氮和全磷的含量,但是否影响高寒草甸植物物种多样性和土壤生态化学计量比间的关系,
3、尚不清楚。本研究以甘南和青海湖流域为对象,采用配对设置样地的方法,分析了高原鼠兔干扰对高寒草甸植物物种多样性和土壤生态化学计量比间关系的影响。结果表明:高原鼠兔干扰显著增加了物种丰富度指数、土壤有机碳、全氮和全磷含量,以及土壤 C N 和 C P(P0.05),但没有显著影响物种多样性指数、物种均匀度指数和土壤 N P。高原鼠兔干扰增加了物种丰富度指数和物种多样性指数与土壤 C N 间的正相关性(P0.05),减弱了物种丰富度指数与土壤 C P 间的正相关性(P0.01);物种多样性指数与土壤 C P 间的关系从高原鼠兔未干扰生境的对数关系转变为干扰生境的二次函数关系(P0.05),而物种丰富
4、度指数与土壤 N P 间的关系从高原鼠兔未干扰生境的不显著相关,改变为干扰生境的显著负相关二次函数(P0.01);物种多样性指数与土壤N P间的关系从未干扰生境的显著正相关二次函数(P0.05),变为干扰生境的不显著相关,这确证了高原鼠兔干扰能够改变植物物种多样性与土壤生态化学计量比间的关系,为全面解释高原鼠兔干扰下草地植物群落结构的维持提供了基础信息。关键词:高原鼠兔干扰;高寒草甸;植物物种多样性;土壤生态化学计量比;相关性Effects of plateau pika(Ochotona curzoniae)disturbance on the relationship between pl
5、ant species diversity and soil ecological stoichiometry in alpine meadowsLIU Cai-feng,DUAN Yuan-yuan,WANG Ling-ling,WANG Yi-mo,GUO Zheng-gang*Engineering Research Center of Grassland Agriculture,Ministry of Education,College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou 7
6、30020,ChinaAbstract:The relationship between plant species diversity and soil ecological stoichiometry is key to maintaining plant community structure in grasslands.Although plateau pika(Ochotona curzoniae)disturbance has been reported to have impacts on plant species diversity and soil C,N and P co
7、ntents,whether plateau pika disturbance influences the relationship between plant species diversity and soil ecological stoichiometry in alpine meadows is not yet well documented.In this study,an experimental survey in the Gannan area of Gansu Province and the Qinghai Lake basins of Qinghai Province
8、 was conducted to investigate the effects of plateau pika disturbance on plant species DOI:10.11686/cyxb2022271http:/收稿日期:2022-06-21;改回日期:2022-09-14基金项目:国家自然科学基金(32171675),中央高校基本科研业务费专项资金(lzujbky-2022-it41)和西藏科技重大专项-西藏草业时空拓展技术模式创新与示范(XZ202101ZD0003N)资助。作者简介:刘彩凤(1999-),女,山西朔州人,在读硕士。E-mail: 通信作者 Corre
9、sponding author.E-mail:Vol.32,No.6ACTA PRATACULTURAE SINICA(2023)diversity,soil ecological stoichiometry and their relationship in alpine meadows.In this research,paired-plots were used to collect data and soil samples.The results of this study showed that plateau pika disturbance significantly incr
10、eased species richness index,soil organic carbon,total nitrogen,total phosphorus contents,soil C N and C P(P0.05),but had no significant effect on species diversity index,species evenness index and soil NP.In addition,plateau pika disturbance increased the positive correlation of species richness in
11、dex and species diversity index with soil C N(P0.05)and weakened the positive correlation between species richness index and soil CP(P0.05).The relationship between species diversity index and soil CP changed from a logarithmic relationship in the absence of plateau pikas to a quadratic relationship
12、 in the presence of plateau pikas(P0.05),and the relationship between species richness index and soil NP changed from an insignificant correlation in the absence of plateau pikas into a significant negative correlation with a quadratic function in the presence plateau pikas(P0.05).The relationship b
13、etween species diversity index and soil NP was a significant positive correlation with a quadratic function in absence of plateau pikas,and became an insignificant correlation in the presence of plateau pikas(P0.05).The findings of this study verify that plateau pika disturbance has impacts on the r
14、elationship between plant species diversity and soil ecological stoichiometry.Our research provides basic information on multiple parameters,relevant to maintenance of plant community structure in alpine meadows in the presence of plateau pikas.Key words:plateau pika disturbance;alpine meadow;plant
15、species diversity;soil ecological stoichiometry;correlation植物和土壤间相互依存和适应的关系,是草地植物群落结构和功能维持的主要途径之一1。虽然土壤养分含量是草地植物正常生长发育的基础2,但不同植物对土壤氮磷的需求特性不同3-4。土壤 C N能够反映土壤为植物提供 N的可利用性,土壤 C P反映植物利用土壤中 P的限制性,土壤 N P反映了植物生长主要受 N还是 P限制5。因此,土壤 C N P 不仅能够测度土壤 N 和 P 的可利用性,而且能够反映植物遭受 N 或 P 的限制。土壤 C N P 因干扰而改变意味着土壤 N 和 P 的利
16、用性随之而改变,导致有些植物生长潜势增强或者为群落内原来没有的物种提供良好生境,而有些植物生长势则会减弱或由于 N 和 P供给不足而退出植物群落6,从而引起植物群落多样性的变化。当植物群落组分变化时,以凋落物形式输入到土壤的有机物质和植物根系分泌物必然有所改变5,这会影响土壤微生物活性,反而又影响土壤 C N P7,因此植物物种多样性与土壤 C N P间是相互影响,密不可分的8-10。已有研究表明,油蒿(Artemisia ordosica)植物群落土壤8,撂荒造林地土壤9,以及弃耕地次生演替土壤10的 C N 和 C P,均与物种多样性指数呈显著正相关。当土壤 C N 逐渐增加时,土壤 N 有效性降低5,此时禾本科植物因喜食氮素而迫使其生长受到抑制6,这会减轻植物群落内禾本科植物对其他物种的竞争压力,从而为低矮和少数机会主义物种提供良好生境,此时植物群落内物种数会增加。撂荒造林地土壤本身缺 P9,土壤开始为 N 限制,逐渐演变为 N 和 P共同限制,后期为 P限制,N 限制会抑制禾本科植物生长,减轻低矮植物的生长压力,N 和 P共同限制时,植物生态位开始分化,有较多物种共存,而 P限