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付志鑫  李雪  刘妍  范亚文 《湖泊科学》2017,29(5):1274-1278
2011-2012年间对扎龙国家级自然保护区的藻类标本进行采集及观察鉴定.研究发现,该区域鼓藻类植物生物多样性较高,共观察到90个分类单位.研究过程中发现宽带鼓藻属的一个新种——Pleurotaenium parvulum Li,FanWei.该物种特征为植物体单细胞,细胞小型,长圆柱形;半细胞顶端平截,其缘边横断面可见5个小结节;细胞壁平滑或具点纹;半细胞具两个轴生星状的色素体,每个色素体具1个蛋白核.本文比较了该物种与其相近种类之间的差异.  相似文献   
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Monthly collections of phytoplankton were supported by physical–chemical data and measures of chlorophyll a concentrations in the search for particular environmental factors that could explain the constant presence of desmids in a Mexican tropical lake, a characteristic not common among the phytoplanktic communities of Mexican lakes. Samplings were taken from the water column in the deepest part of the lake (40 m) and intensified in the metalimnetic zone, whose establishment was monitored by observations of temperature and oxygen profiles. The general behavior of Lake Zirahuén was typical of warm monomictic tropical lakes at high elevation: a short mixing phase during the hemispheric winter. The depth of ZMIX and Zeu revealed a well-illuminated epilimnion, suggesting that phytoplankton communities are not likely to be light-limited. The oligotrophic nature of the lake is indicated by discrete concentrations of inorganic nutrients, PTOT in the interval of 0.01–0.03 mg l−1 and chlorophyll a between 0.23 and 3.98 μg l−1. These characteristics together with a low concentration of calcium, define a lacustrine environment different from other Mexican lakes, and one that could be suitable for desmids communities.  相似文献   
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