Intra-specific genetic diversity and ecophysiological performance of the aeroterrestrial green alga Klebsormidium (Klebsormidiophyceae, Streptophyta) in biological soil crusts along a gradient of land-use intensity

沿土地利用强度梯度的生物土壤结皮中陆生绿藻 Klebsormidium（Klebsormidiophyceae，Streptophyta）的种内遗传多样性和生态生理学性能

• 批准号: 191091616
• 负责人: Professor Dr. Ulf Karsten
• 金额: --
• 依托单位: Lehrstuhl Angewandte Ökologie und Phykologie
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/191091616?language=en
• 关键词: Intra; specific; genetic; diversity; ecophysiological

Aeroterrestrial filamentous green algae of the widely distributed, cosmopolitan genus Klebsormidium (Klebsormidiophyceae, Streptophyta) are typical components of biological soil crusts. These communities occur in all climatic zones and on all continents on Earth, where soil moisture is limiting. Biological crusts form water-stable aggregates that have important ecological roles in primary production, nitrogen fixation, nutrient cycling, water retention and stabilization of soils. Although available data on Klebsormidium are generally limited, its functional importance in biological soil crusts is regarded as high. Therefore, Klebsormidium will be investigated under different land-use intensities, as provided by the Biodiversity Exploratories, and in a changing world by a comprehensive evaluation of its intra-specific genetic diversity and ecophysiological performance. Such a combined approach has never been applied before to aeroterrestrial green algae, and hence represents one of the key innovations of this proposal. A representative set of soil samples will be collected from the experimental plots of the 3 research site in the Biodiversity Exploratories, from which unialgal Klebsormidium cultures will be established. Molecular-taxonomical characterisation of these strains will be undertaken using 18s rDNA, ITS-2 and rbcL markers. The intra-specific genetic diversity of strains of the same species will be evaluated using microsatellites. Based on the molecular data a range of selected genotypes of the same Klebsormidium species will be ecophysiologically characterised by comparatively measuring growth and photosynthesis as function of light, temperature, water and nutrient gradients to identify the physiological plasticity and ecological limits within the respective population. The data will indicate whether and how changes in land-use intensity will influence population structure and ecological performance of Klebsormidium in soil crusts.

气生丝状绿色藻类广泛分布于世界各地的克雷伯藻属（Klebsormidiophyceae，Streptophyta），是生物土壤结皮的典型组成部分。这些群落出现在地球上所有气候带和所有大陆，土壤水分有限。生物结皮形成水稳性聚集体，在初级生产、固氮、养分循环、保水和土壤稳定方面具有重要的生态作用。虽然克雷伯菌属的现有数据普遍有限，但其在生物土壤结皮中的功能重要性被认为很高。因此，Klebsormidium将在不同的土地利用强度下进行调查，由生物多样性探索中心提供，并在不断变化的世界中，通过对其种内遗传多样性和生理生态性能的综合评价。这样的组合方法以前从未应用于气地绿色藻类，因此代表了该提议的关键创新之一。将从生物多样性探索站的3个研究点的实验地块中收集一组具有代表性的土壤样品，并从中建立单藻克雷伯藻培养物。这些菌株的分子分类特征将进行使用18 S rDNA，ITS-2和rbcL标记。将使用微卫星评价同一物种菌株的种内遗传多样性。基于分子数据，将通过比较测量生长和光合作用作为光、温度、水和营养梯度的函数来对相同克雷伯菌属物种的一系列选定基因型进行生理生态学表征，以确定相应种群内的生理可塑性和生态极限。这些数据将表明土地利用强度的变化是否以及如何影响土壤结皮中克雷伯氏菌的种群结构和生态表现。