植物生态学报 ›› 2019, Vol. 43 ›› Issue (5): 418-426.doi: 10.17521/cjpe.2018.0317

• 研究论文 • 上一篇    下一篇

甘南高寒草甸群落的物种-多度关系沿坡向的变化

李全弟,刘旻霞(),夏素娟,南笑宁,蒋晓轩   

  1. 西北师范大学地理与环境科学学院, 兰州 730070
  • 收稿日期:2018-12-18 接受日期:2019-05-12 出版日期:2019-05-20 发布日期:2019-10-18
  • 通讯作者: 刘旻霞 E-mail:xiaminl@163.com
  • 基金资助:
    国家自然科学基金(31760135);国家自然科学基金(31360114)

Changes in species-abundance relationships of plant communities with slopes in alpine meadows of Gannan, China

LI Quan-Di,LIU Min-Xia(),XIA Su-Juan,NAN Xiao-Ning,JIANG Xiao-Xuan   

  1. College of Geography and Environmental Sciences, Northwest Normal University, Lanzhou 730070, China
  • Received:2018-12-18 Accepted:2019-05-12 Online:2019-05-20 Published:2019-10-18
  • Contact: LIU Min-Xia E-mail:xiaminl@163.com
  • Supported by:
    Supported by the National Natural Science Foundation of China(31760135);Supported by the National Natural Science Foundation of China(31360114)

摘要:

物种-多度格局研究是揭示群落组织结构和物种区域分布规律的重要手段。该研究以青藏高原东北部的甘南高寒草甸为研究对象, 基于野外调查和室内分析, 研究了不同坡向的环境因子、植物群落分布, 并利用RAD软件程序包对其进行了拟合分析。结果显示: 在南坡-北坡上, 土壤含水量从南坡(0.18 g·g -1)到北坡(0.31 g·g -1)呈现递增的趋势, 土壤温度从南坡(22.33 ℃)到北坡(18.13 ℃)以及光照强度从南坡(744.15 lx)到北坡(681.93 lx)均呈逐渐减小的趋势。物种-多度分布曲线的斜率从南坡向北坡依次减小。随着坡向由南向北转变, 物种-多度和物种多样性都呈递增的趋势。通过6个模型对坡向梯度的物种-多度分布进行拟合发现, 甘南高寒草甸区的物种-多度分布主要是以生态位模型为主, 其次是随机分布模型。青藏高原高寒草甸微生境梯度上的物种在总体上的资源分配模式是以固定分配模式为主, 稀有种的资源分配模式是以随机性模型为主, 常见种的资源分配模式则是以确定性模型为主。

关键词: 甘南高寒草甸, 坡向, 物种-多度, 常见种, 稀有种

Abstract:
Aims The study of species diversity patterns is useful in understanding community structure and resource allocation patterns in the succession process in alpine meadows. The present study aims to explore: 1) the changes in community species-abundance relationships in alpine meadows of the Qinghai-Xizang Plateau with mountain slopes; and 2) the difference between the abundances of common and rare species, and their roles in the ecological mechanisms. Methods Field investigation was carried out in alpine meadows of the Qinghai-Xizang Plateau followed by lab analyses in Lanzhou. RAD was used to analyze the difference in environmental factors and plant communities among different slope aspects. Important findings Soil water content increased gradually from the south to north slopes (from 0.18 g·g -1 on the south slope to 0.31 g·g -1 on the north slope), while soil temperature and light intensity showed the opposite trends (from 22.33 ℃ and 744.15 lx on the south slope to 18.13 ℃ and 681.93 lx on the north slope, respectively). The species abundance and species diversity increased, while the slope of species abundance curves decreased from the south to north slopes. Among the six species abundance fitting models, the ecological niche model best explained the species abundance curves followed by the random distribution model. Further analysis showed that the overall resource allocation pattern of species was mainly fixed distribution. In addition, the resource allocation pattern of the rare species was mainly random, while that of the common species was mainly deterministic.

Key words: Gannan alpine meadow, slope gradient, species-abundance, common species, rare species