茂兰喀斯特森林不同演替阶段植物叶片功能性状与土壤因子的关系

Relationship between plant leaf functional traits and soilfactors at different succession stages in karst forest of Maolan

关键词:  喀斯特森林, 演替阶段, 叶片功能性状, 土壤因子, 生态策略

Key words:  karst forest, succession stage, leaf functional traits, soil factors, ecological strategy

摘要:

植物如何改变功能性状来适应环境一直是生态学的研究征点。为探究茂兰喀斯特森林不同演替阶段植物叶片的适应策略,该文以茂兰自然保护区5个不同演替阶段(草本、灌木、灌乔、乔木和顶极群落阶段)优势种为研究对象,测定不同演替阶段的优势植物叶片功能性状与土壤理化性质。结果表明:(1)随着植被正向演替的进行,土壤全氮(STN)含量、土壤有机质(SOM)含量、土壤含水量(SWC)逐渐增加,土壤全磷(STP)含量和土壤全钾(STK)含量先增加后减少,土壤pH值整体呈减小的趋势。(2)随着植被演替的进行,叶面积(LA)、叶干物质含量(LDMC)、叶厚度(LT)和叶片碳含量(LCC)逐渐上升,比叶面积(SLA)与叶片钾含量(LKC)则与之相反,叶片氮含量(LNC)呈先升后降的趋势,叶片磷含量(LPC)呈先降后升的趋势。(3)冗余分析表明,演替初期植物主要分布在土壤pH值高而STK、STP、SWC、SOM、STN相对低的环境中,群落内植物叶片采取高SLA、LNC、LPC,低LA、LDMC、LT、LWC的性状组合,演替晚期植物主要分布在土壤水分和养分含量较高的环境,LDMC、LT、LA、LWC与演替初期相比呈上升趋势,SLA、LNC、LPC与演替初期相比呈下降趋势。综上表明,随着植被演替的进行,植物通过改变功能性状来适应环境,叶片功能性状由演替初期的开放性策略转向后期的保守性策略。

Abstract:

How plants change functional traists to adapt to the environment has always been the focus of ecology. In order to explore the adaptive strategies of plant leaves at different succession stages in karst forest of Maolan, taking the dominant species in five different succession stages( herb, shrub, shrub-arbor, arbor and climax community stages)in Maolan Nature Reserve as the research object, the leaf functional properties and soil physical and chemical properties of dominant plants at different succession stages were measured. The results were as follows:(1)With the succession of vegetation, soil total nitrogen(STN)content, soil organic matter(SOM)content and soil water(SWC)content gradually increased, soil total phosphorus(STP)content and soil total potassium(STK)content first increased and then decreased, and soil pH value showed a decreasing trend as a whole.(2)With the succession of vegetation, leaf area(LA), leaf dry matter content(LDMC), leaf thickness(LT)and leaf carbon content(LCC)gradually increased. On the contrary, specific leaf area(SLA)and leaf potassium content(LKC), leaf nitrogen content(LNC)increased first and then decreased, and leaf phosphorus content(LPC)decreased first and then increased.(3)Redundant analysis showed that plants were mainly distributed in the soil environment of high pH and relatively low STK, STP, SWC, SOM and STN at the early succession stage. Plant leaves in the community took high SLA, LNC and LPC, and low LA, LDMC, LT and LWC. Plants at the late succession stage were mainly distributed in the soil environment of high moisture and nutrients. LDMC, LT, LA and LWC showed an upward trend compared with the early succession stage, and SLA, LNC and LPC showed a downward trend compared with the early succession stage. In conclusion, with the forward succession of vegetation, plants adapt to the environment by changing functional traits, and leaf functional traits change from open strategy in the early succession stage to conservative strategy in the late succession stage.