Iran is a large country with a great diversity of aquatic ecosystems including rivers, springs, shallow seas, lakes, waterfalls, lagoons, and wetlands. Despite the many types of aquatic habitats, there has been a limited study of the diatom flora. The purpose of this study is to present the diatom species and characterize their distribution in the Karaj River, which flows in Iran’s Central Alborz region. The Alborz is one of the Irano-Anatolian ecoregions that serve as biodiversity hotspots. The Central Alborz, located in the middle part of this mountainous area, is an outstanding ecological and geological resource. This study uses the diatom flora to determine the biodiversity in one of the major rivers of the Central Alborz. Periphytic diatom samples were collected monthly from six stations along the length of the Karaj River between May 2011 and April 2012. A total of 128 diatom taxa was found from 48 genera expanding our understanding of regional aquatic diversity as 42 species are recorded as new for the diatom flora of Iran. Furthermore, the biogeography of the diatom flora of the Karaj River is considered in relation to the rest of Iran, the Middle East, and Asian and European diatom communities.

中文翻译：

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伊朗阿尔伯兹中部卡拉季河中硅藻的生物多样性

伊朗是一个拥有多种水生生态系统的大国，包括河流、泉水、浅海、湖泊、瀑布、泻湖和湿地。尽管有许多类型的水生栖息地，但对硅藻群的研究仍然有限。本研究的目的是展示硅藻种类并描述它们在卡拉季河中的分布特征，卡拉吉河流经伊朗中部阿尔伯兹地区。Alborz 是作为生物多样性热点的伊朗-安纳托利亚生态区之一。Central Alborz 位于该山区的中部，是一个杰出的生态和地质资源。本研究使用硅藻群来确定中央阿尔伯兹省的一条主要河流中的生物多样性。2011 年 5 月至 2012 年 4 月期间，每月从卡拉季河沿岸的六个站点收集附生硅藻样本。共发现 128 个硅藻类群，来自 48 个属，扩大了我们对区域水生多样性的理解，因为有 42 个物种被记录为新物种伊朗的硅藻群。此外，还考虑了与伊朗其他地区、中东以及亚洲和欧洲硅藻群落相关的卡拉季河硅藻群落的生物地理学。