喀纳斯景区山地草甸不同退化阶段群落共有种的生态化学计量特征研究  

Ecological stoichiometry characteristics of common species in mountain meadows at different stages of degraded succession in the Kanas Scenic Area

作　　者：唐高溶[1] 郑伟[1,2] 王祥[1] 朱亚琼[1] 吴燕锋[1] 

机构地区：[1]新疆农业大学草业与环境科学学院,新疆乌鲁木齐830052 [2]新疆维吾尔自治区草地资源与生态重点实验室,新疆乌鲁木齐830052

出　　处：《草业学报》2016年第12期63-75,共13页Acta Prataculturae Sinica

基　　金：国家自然科学基金项目(31460636);中国科学院战略性先导科技专项(XDA05050405)资助

摘　　要：通过在新疆喀纳斯景区山地草甸群落中对不同退化阶段4个典型样点进行样方调查与采样,结合室内分析,探究了不同退化阶段山地草甸群落共有植物及土壤的碳(C)、氮(N)、磷(P)化学计量特征及其内在联系,揭示了山地草甸生态系统养分循环规律和系统稳定机制。研究结果表明,1)3种群落共有植物的重要值、盖度、密度和生物量都随着草地的退化加剧而上升,平均高度和叶绿素相对含量随着退化的加剧而降低。2)随着草地退化程度的增加,群落共有种C、N、P含量均下降,草甸早熟禾C∶N则先降低后升高,其余2种共有种均上升;群落Ⅰ中3种共有植物叶片的N∶P都在14和16之间,剩余3个群落中,草甸早熟禾叶片N∶P高于16,而千叶蓍和短柄苔草叶片的N∶P均小于14。3)叶绿素相对含量与植物的N含量呈显著的正相关,植物盖度与其化学计量比的相关性不显著,植物的高度、密度、生物量与其化学计量比相关性的显著性取决于物种和生境。4)土壤的C、N、P含量均影响植物的C、N、P含量,呈显著的线性正相关。喀纳斯景区未退化阶段的植物生长受N、P双重元素的限制或者均不受限,退化阶段的植物生长主要受N的限制。因此,喀纳斯景区山地草甸土壤生态化学特征对退化山地草甸的植被恢复有着重要影响。The overall aim of this research was to analyze nutrient cycling and the ecosystem stability mechanisms of mountain meadows.We analyzed the stoichiometry characteristics of carbon（C）,nitrogen（N）,and phosphorus（P）in three common species（Poa pratensis,Carex pediformis,Achillea millefolium）and soil in mountain meadows at different stages of degradation in the Kanas Scenic Area,Xinjiang Uygur Autonomous Region.The results showed that：1）the importance values,coverage,density,and biomass of the three species increased with increasing degrees of degradation of the mountain meadows,but the average plant height and chlorophyll content of leaves decreased.2）The C,N,and P contents of common species decreased with increasing degradation.The C∶N of P.pratensis increased from community Ⅰ to Ⅱ and then decreased.The C∶N of other common species increased with increasing degradation.The N∶P of three common species ranged from 14 to 16in communityⅠ.In other communities,the N∶P exceeded 16 in P.pratensis,but was lower than 14 in A.millefoliumand C.pediformis.3）There was a positive relationship between chlorophyll content and leaf N content.There was no correlation between coverage and the stoichiometric ratio of leaves and soil.The significance of correlations between plant height,density,biomass,and stoichiometric ratios depended on the species and habitats.4）There were positive,significant,linear correlations between C,N,P contents in soil and in leaves.Plant growth in non-degraded meadows was mainly restricted by soil N and P or not restricted,and it was mainly restricted by soil N in degraded meadows.Together,these results show that soil nutrient stoichiometry has important effects on vegetation recovery in mountain meadows.

关 键 词：山地草甸 退化阶段 共有种 生态化学计量 营养限制 

分 类 号：S812[农业科学—草业科学]