植物生态学报 ›› 2016, Vol. 40 ›› Issue (8): 775-787.doi: 10.17521/cjpe.2015.0288

• 研究论文 • 上一篇    下一篇

不同雪被厚度下典型高山草地早春植物叶片性状、株高及生物量分配的研究

高景1,2, 王金牛1,3,,A;*(), 徐波1,2, 谢雨1,2, 贺俊东1,2, 吴彦1,,A;*()   

  1. 1中国科学院成都生物研究所, 成都 610041
    2中国科学院大学, 北京 100049
    3International Centre for Integrated Mountain Development (ICIMOD), Kathmandu, Nepal
  • 出版日期:2016-08-10 发布日期:2016-08-23
  • 通讯作者: 王金牛,吴彦 E-mail:wangjn@cib.ac.cn;wuyan@cib.ac.cn

Plant leaf traits, height and biomass partitioning in typical ephemerals under different levels of snow cover thickness in an alpine meadow

Jing GAO1,2, Jin-Niu WANG1,3,*(), Bo XU1,2, Yu XIE1,2, Jun-Dong HE1,2, Yan WU1,*()   

  1. 1Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China

    2University of Chinese Academy of Sciences, Beijing 100049, China

    3International Centre for Integrated Mountain Development (ICIMOD), Kathmandu, Nepal
  • Online:2016-08-10 Published:2016-08-23
  • Contact: Jin-Niu WANG,Yan WU E-mail:wangjn@cib.ac.cn;wuyan@cib.ac.cn

摘要:

在高寒生命带, 雪被作为重要的综合环境因子, 影响着植物的生理生态特征、种群动态及群落演替等过程, 进而作用于生态系统的功能与服务。通过在青藏高原东缘高寒草甸设置厚雪、中雪和浅雪3个地段, 选取早春开花的常见种紫罗兰报春(Primula purdomii)、甘肃马先蒿(Pedicularis kansuensis)、高原毛茛(Ranunculus tanguticus), 研究了三种植物株高、叶片性状和生物量分配随雪被厚度的变化规律, 以及三者之间的关系。结果表明: 甘肃马先蒿和高原毛茛在生境状况较好的地段比叶面积相对较高, 紫罗兰报春由于具有根状茎和肉质根, 在厚雪地段比叶面积相对较小; 关于单个物种的地上-地下生物量的关系, 紫罗兰报春在厚雪和浅雪地段为完全一致的异速生长关系, 而甘肃马先蒿和高原毛茛在个别地段并无显著相关关系。总体而言, 三种植物整体样本的地上-地下生物量在不同雪被地段均为异速生长关系, 不支持等速生长假说, 并且地上生物量能够很好地解释地下生物量的变异; 功能性状和生物量指标间的相关性, 在紫罗兰报春和高原毛茛表现较好, 而在甘肃马先蒿表现较弱。植物对环境变化的适应具有一定的规律, 同时也表现出物种特异性。今后的研究中, 应注重构建植物适应环境变化的功能性状谱, 以更好地理解全球变化背景下植物功能性状的响应及其适应策略。

关键词: 雪被厚度, 早春植物, 比叶面积, 株高, 生物量分配, 异速生长

Abstract:
Aims In the cold life zones, snow cover is a comprehensive environmental factor that directly influences soil temperature, soil water content, light and nutrient availability. Plants in these zones develop a series of unique mechanisms involving phenological characteristics, reproductive strategies, physiology and morphology to adapt to environmental changes. This paper is focused on the responses of plant leaf traits, height and biomass partitioning to variations in snow cover thickness, in order to better understand the responses of plant functional traits and specific adaptation strategies under global climate change scenarios. Methods Three transects were established along a gradient of snow cover in an alpine meadow of Mt. Kaka, in the eastern Qinghai-Xizang Plateau. Primula purdomii, Pedicularis kansuensis and Ranunculus tanguticus, which are three widely distributed and dominant ephemerals, were sampled and studied, particularly at their blooming stages. Plant height, specific leaf area (SLA) and biomass partitioning were measured accordingly. Important findings The values of SLA in Pedicularis kansuensis and R. tanguticus were relatively greater under better soil conditions; it was smaller in Primula purdomii with thick snow cover. The relationship between aboveground biomass and belowground biomass in Primula purdomii was allometric at sites with both thick and thin snow cover. No significant relationships were found between aboveground biomass and belowground biomass in Pedicularis kansuensis and R. tanguticus at some individual sites. However, when samples of the three species were pooled, the relationships between aboveground biomass and belowground biomass were allometric at all sites, which did not support isometric scaling hypothesis. In addition, on sites with either thick or thin snow cover, aboveground biomass had greater rate of accumulation than belowground biomass; whereas on sites with medium snow cover, the rate of biomass accumulation was greater for belowground component than aboveground component. Functional traits and biomass variables were better correlated in Primula purdomii and Pedicularis kansuensis than in R. tanguticus.

Key words: snow cover thickness, ephemeral plant, special leaf area, plant height, biomass partitioning, allometric scaling