云南高原湖泊硅藻群落与生物多样性的分布特征研究

发布时间：2018-02-27 06:22

本文关键词： 云南湖泊古湖沼学时空尺度硅藻生产力-生物多样性模式　出处：《云南师范大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来全球变暖的持续与土地利用等人类活动的加剧明显改变了自然生态系统的结构与功能,生物多样性的保护面临着巨大挑战。湖泊作为特殊的自然综合体,正在面临着富营养化、工业污染、水文改造等多种环境压力的胁迫,并严重影响了水生生物的群落组成和生物多样性的分布模式。云南地区具有丰富的气候和地貌类型,造就了丰富的生物多样性,是全球生物多样性研究的热点地区之一。目前,对云南生物多样性的研究主要集中于陆地生态系统和短期的现代调查,对以湖泊为代表的水生生态系统和生物多样性长期变化的模式特征研究不足。因此,急需我们对云南湖泊生物多样性的时空分布格局与主要环境压力进行识别,从而为有效的保护云南湖泊生物多样性与生态修复提供重要的基础数据与科学依据。本文拟通过古湖沼学方法和相关数理统计分析,系统识别云南22个湖泊硅藻群落和生物多样的空间分布特征及其主控环境因子,并通过抚仙湖与滇池沉积物硅藻记录揭示湖泊生产力长期变化驱动生物多样性变化的时间格局。研究结果表明:1)空间尺度上,22个湖泊硅藻群落的分布主要受到湖泊形态、水化学特征和湖泊生产力的驱动;近百年来,抚仙湖与滇池硅藻群落的变化主要受湖泊生产力水平的长期驱动。2)云南湖泊部分硅藻是指示生态环境变化的敏感物种,如Cyclotella ocellata是严格意义上的贫营养物种,而Nitzschia gracilis可指示水体的富营养水平。3)基于硅藻群落的α和β多样性指标,在响应湖泊生产力变化的时空模式上具有高度的一致性;空间尺度上浅水和深水湖泊中呈现一致的单峰模式;而时间尺度上,不同类型湖泊的硅藻多样性随着生产力的增加存在两种不同的响应模式;4)不同营养水平下,硅藻生物多样性对硅藻群落生产力的维持作用存在差异,反映了人类活动的扰动对生物多样维持生态系统功能的调节作用。
[Abstract]:In recent years, the persistence of global warming and the intensification of human activities, such as land use, have obviously changed the structure and function of natural ecosystems, and the conservation of biodiversity is facing great challenges. It is facing the stress of various environmental pressures, such as eutrophication, industrial pollution, hydrological transformation and so on, and has seriously affected the community composition and biodiversity distribution pattern of aquatic organisms. Yunnan has rich climatic and geomorphologic types. It is one of the hotspots of biodiversity research in the world. At present, the research on biodiversity in Yunnan is mainly focused on terrestrial ecosystems and short-term modern surveys. Therefore, it is urgent for us to identify the spatial and temporal distribution patterns and the main environmental pressures of lake biodiversity in Yunnan Province, because of the lack of research on the model characteristics of long-term changes in aquatic ecosystems and biodiversity, which are represented by lakes. Therefore, this paper provides important basic data and scientific basis for the effective protection of biodiversity and ecological restoration of Yunnan lakes. The spatial distribution characteristics of diatom community and biological diversity in 22 lakes of Yunnan Province and their main controlling environmental factors were systematically identified. Diatoms in Fuxian Lake and Dianchi Lake sediments were recorded to reveal the temporal pattern of long-term changes in lake productivity driving biodiversity changes. The results showed that the distribution of diatom communities in 22 lakes was dominated by lake morphology on the spatial scale of 1: 1. The changes of diatom community in Fuxian Lake and Dianchi Lake were mainly driven by lake productivity level for a long period of time. 2) some diatoms in Yunnan Lake were sensitive species indicating the change of ecological environment. For example, Cyclotella ocellata is a strictly poor nutrient species, and Nitzschia gracilis can indicate the eutrophication level of water body. 3) based on 伪 and 尾 diversity indexes of diatom community, there is a high consistency in the spatio-temporal model of response to the change of lake productivity. On spatial scale, there is a single peak model in shallow water and deep water lakes, but on time scale, there are two different response models for diatom diversity in different types of lakes with increasing productivity. The diversity of diatoms on the maintenance of diatom community productivity is different, reflecting the disturbance of human activities on the regulation of biodiversity to maintain ecosystem functions.
【学位授予单位】：云南师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X524;X173

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