新疆的微藻及其群落结构

摘要

为了解新疆的微藻资源及其群落特征，研究于2013年5月和2014年6月对新疆包括荒漠、草甸、农田、滩涂等土壤生境和湖泊、水库、河流、池塘、沟渠等水体生境中的微藻进行了采样调查，共采集到标本329个，其中水样256个，土样73个。经室内鉴定发现，陆生藻有77种，优势种呈蓝藻-绿藻型，主要是席藻属(Phormidium)的种类、具鞘微鞘藻(Microcoleus vaginatus)、土生绿球藻(Chlorococcum humicola)；水生藻有272种，优势种呈绿藻-硅藻-蓝藻型，主要集中在颤藻属(Oscillatoria)、席藻属(Phormidium)、栅藻属(Scenedesmus)、单针藻属(Monoraphidium)和舟形藻属(Navicula)。整体而言，北部中温带干旱区的微藻较南部暖温带极端干旱区更丰富，而且主要集中在中温带干旱区的滩涂、湖泊和河流生境。依多维尺度分析发现，土壤生境下同一气候区的滩涂和草甸的微藻群落结构较为相似，荒漠和农田生境的群落结构无气候区域差异。在水生生境下，暖温带极端干旱区河流中的群落结构与其他4种水境中差别较大；中温带干旱区的湖泊和河流相似，其他生境中的差别都较大，这说明气候带和生境类型都对微藻群落有影响。%We conducted studies in May 2013 and June 2014 in Xinjiang to better understand the community structure of microalgae in this area and the impacts of habitational environments on their distribution. The sampling sites were lo-cated in different aquatic (lakes, rivers, ditches, ponds, reservoirs) and terrestrial (deserts, meadows, farmlands, shal-lows) habitats in Xinjiang. Two hundred and twenty microalgae samples were collected including 185 water samples and 35 soil samples. Seventy-seven species of terrestrial microalgae were identified, and 9 of them (mainly Cyanophyta and Chlorophyta) were dominant, such asPhormidium, Microcoleus vaginatus, andChlorococcum humicola. There were 272 of aquatic species, 42 of which were dominant, and the dominant species were a complex of Chlorophyta, Bacil-lariophyta and Cyanophyta, includingOscillatoria,Phormidium,Scenedesmus,Monoraphidium,Navicula and so on. Compared to the southern warm-temperate extreme arid zone, microalgae species were more abundant in the northern mid-temperate arid zone, especially enriched in shallows, rivers and lakes. According to the multidimensional scaling analysis, terrestrial habitats such as beaches and meadows had similar community structures of microalgae in the same climate zone, while deserts and farmlands had the same community structure in spite of the climate difference. As for the aquatic habitats, there were remarkable differences in the community structure between rivers and other 4 aquatic habitats in the warm-temperate extreme arid zone; in the mid-temperate arid zone, the community structures in the lakes and rivers were similar, but there was a great difference among other aquatic habitats. Our study indicated that different climates and habitational environments may have impacts on microalgae species.