生物多样性 ›› 2015, Vol. 23 ›› Issue (1): 89-100.DOI: 10.17520/biods.2014213

• 研究报告: 生态系统多样性 • 上一篇    下一篇

抚仙湖和滇池硅藻生物多样性与生产力关系的时间格局

陈小林1, 陈光杰1*, 卢慧斌1, 刘晓东2, 张虎才1   

  1. 1云南师范大学旅游与地理科学学院高原湖泊生态与全球变化重点实验室, 昆明 650500
    2中国科技大学地球与空间学院, 合肥 239000
  • 收稿日期:2014-10-09 修回日期:2014-11-21 出版日期:2015-01-20 发布日期:2015-05-04
  • 通讯作者: 陈光杰
  • 基金资助:

    国家自然科学基金项目;教育部科学技术研究项目;云南省中青年学术技术带头人培养计划;云南省创新团队;云南省高端人才项目

Long-term diatom biodiversity responses to productivity in lakes of Fuxian and Dianchi

Xiaolin Chen1, Guangjie Chen1*, Huibin Lu1, Xiaodong Liu2, Hucai Zhang1   

  1. 1Key Laboratory of Plateau Lake Ecology & Global Change, School of Tourism & Geography, Yunnan Normal University, Kunming 650500

    2School of Earth and Space Science, University of Science and Technology of China, Hefei 239000
  • Received:2014-10-09 Revised:2014-11-21 Online:2015-01-20 Published:2015-05-04
  • Contact: Guangjie Chen

摘要:

目前国内对生产力–生物多样性关系(productivity–diversity relationship, PDR)的研究主要集中于陆地生态系统和空间尺度, 少量关于湖泊系统的研究也主要集中于现代调查, 缺乏较长时间尺度上的模式探讨。本文应用沉积物色素记录重建了抚仙湖和滇池初级生产力变化历史, 对硅藻群落的主成分分析(PCA)表明两个湖泊的初级生产力都是驱动硅藻群落变化的主要环境梯度。进一步分析硅藻群落α与β多样性响应湖泊生产力水平的模式, 发现滇池硅藻群落表现为随着系统生产力的上升物种丰富度减少, β多样性降低, 而抚仙湖呈现相反的变化模式。两个湖泊β多样性与生产力平均水平的关系均表现出与α多样性相似的特征, 但在与生产力变化幅度的关系上, 滇池表现出显著的负相关, 而抚仙湖则没有显著的变化。滇池硅藻群落生产力随硅藻多样性的降低显著增加(R2 = 0.597, P < 0.01), 而在抚仙湖无显著变化, 表明了滇池群落多样性的维持对群落生产力的影响较弱, 如与营养盐富集的促进作用相比。滇池明显的富营养化过程与强烈的人类扰动带来的环境异质性降低可能对群落多样性–生产力的关系产生了明显的控制作用。

关键词: 云南湖泊, 硅藻, 时间尺度, 沉积物色素, 富营养化, 生物多样性

Abstract:

To date, productivity–diversity relationships (PDR) in terrestrial ecosystems have predominantly been examined across large spatial scales, while freshwater ecosystem studies typically focus on short-term field surveys. Here sediment records are used to examine the long-term patterns of PDR from two large lakes, Fuxian and Dianchi, which are currently oligo-mesotrophic and hyper-eutrophic, respectively. Changes in lake productivity and community structure were reconstructed based on sedimentary pigment concentrations (i.e. Chl-a) and diatom assemblages. Principal Component Analysis (PCA) of diatom community data showed that primary productivity was the most significant environmental gradient driving diatom community changes in both lakes. Lake productivity was positively correlated to diatom alpha- and beta-diversity indices in Lake Fuxian but negative in Lake Dianchi. The relationship between the magnitude of productivity change and diatom beta-diversity was significantly negative in Lake Dianchi while no trend was found in Lake Fuxian. There was a significantly negative relationship between diatom species richness and community productivity in Lake Dianchi, suggesting the influence of increased species richness in enhancing community productivity was overridden by human disturbances. Disturbance associated changes in limnological properties not only caused the loss of biodiversity, but also directly promoted diatom production through intensive nutrient enrichment.

Key words: Yunnan lakes, diatoms, temporal scale, sediment pigment, eutrophication, biodiversity