高级检索

    高寒草甸植物叶片氮和磷重吸收率对养分添加的响应及机理

    Response and mechanism of plant leaf nitrogen and phosphorus resorption efficiency to nutrient addition in an alpine meadow

    • 摘要:
      目的 本研究旨在揭示植物叶片氮和磷重吸收率对氮磷添加及交互作用的响应和机理,明确高寒草甸植物养分利用策略多样性。
      方法 以高寒草甸优势植物(垂穗披碱草、发草、灰苞蒿和鹅绒委陵菜)为研究对象,基于氮和磷添加两因子交互试验,研究高寒植物叶片养分重吸收率对养分添加的响应。
      结果 (1)禾本科叶片氮重吸收率随氮添加而增加,但杂类草叶片不受影响;此外,4种植物叶片磷重吸收率均不受氮添加的影响。(2)磷添加对所有植物叶片氮重吸收率和两种杂类草叶片磷重吸收率没有显著影响,但提高了禾本科叶片的磷重吸收率。(3)氮和磷共同添加降低了垂穗披碱草、灰苞蒿和鹅绒委陵菜叶片氮重吸收率,但提高了发草叶片的氮重吸收率。此外,氮和磷同时添加对4种植物叶片磷重吸收效率没有显著影响。
      结论 综上所述,本研究揭示了养分富集下高寒植物3种不同的养分重吸收策略,即对外源获取的养分全部重吸收(绿叶养分增加但凋落叶不增加)、部分重吸收(绿叶和凋落叶同时增加,但凋落叶增加较慢)和不进行重吸收(绿叶和凋落叶均增加,但凋落叶的幅度大于或等于绿叶;或绿叶和凋落叶不响应)。这些研究结果为理解高寒植物养分内循环策略的多样性和互补性提供了一定的启示。

       

      Abstract:
      Objective The purpose of our study was to reveal the response and mechanism of plant leaf nutrient resorption efficiency to nitrogen and phosphorus addition and their interaction, and to clarify the diversity of plant nutrient use strategies in alpine meadows.
      Method To answer this question, we performed an experiment of N and P addition in an alpine meadow, measured leaf nutrient resorption efficiency in four dominant species (Elymus nutans, Deschampsia cespitosa, Artemisia roxburghiana, Potentilla anserina).
      Result (1) N addition had positive effects on leaf N resorption efficiency (NRE) in graminoids, but the leaf NRE of forbs was not affected by N addition, while it did not affect P resorption efficiency (PRE) among four plant species. (2) P addition had no significant effect on the leaf NRE of all plants and the leaf PRE of two forbs, but increased the leaf PRE of graminoids. (3) N and P addition together reduced leaf NRE in E. nutans, A. roxburghiana and P. anserina, but increased NRE in D. cespitosa. Moreover, the combination of N and P addition had not significant effect on leaf PRE of four plants.
      Conclusion Overall, our study indicates that alpine plants adopt three nutrient resorption strategies for more nutrient supply: full resorption (increase green leaf nutrient but no change in senescent leaf), partial resorption (more increase in green leaf nutrient than senescent leaf) and no resorption (similar increase in green and senescent leaf nutrient). These findings provide implications for understanding the diversity and complementarity of nutrient internal circulation strategies in alpine plants.

       

    /

    返回文章
    返回