Terrestrial mosses which retain moisture provide a suitable ambience for diatoms colonization and suitable experimental platforms for observing climate change impact. The distribution and diversity patterns of such epibryic diatom communities are governed by various biotic and abiotic factors of moss habitats. The present study is first of ever attempt to investigate the moss-inhabiting diatoms in relation to various abiotic environmental variables from the Indian Himalayan Region (IHR). Samples were collected from 23 different sites in the Neora Valley National Park in Eastern Himalayas and analyzed through standard methods. Two-way indicator species analysis (TWINSPAN) and cluster analysis (CA) performed to classify the samples and habitats while direct canonical correspondence analysis (CCA) was used to determine the linkage between moss-inhabiting diatom species from various sample and abiotic environmental gradients. A total of 27 diatoms found colonizing on terrestrial moss patches from 23 sites of the park. CCA ordination plots showed that pH, conductivity and relative humidity were the primary factors influencing the diatom diversity and distribution, but altitude and temperature had no influence on the species distribution. But, correlation study on the average valve length of the most abundant and frequent taxa of Neora Valley National Park, i.e. Eunotia paludosa, E. bigibba and Hantzschia amphioxys, in relation to the environmental variables like, altitude, moisture content, relative humidity and temperature revealed a significant inference. The average valve length of these three diatoms decreases in warmer and drier climatic conditions at lower altitudes. Thus, these can be considered as potential indicator species to observe any climate change.

中文翻译：

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印度Neora谷国家公园（东部喜马拉雅山）的苔藓栖硅藻作为生态指标

保留水分的陆地苔藓为硅藻的定殖提供了合适的环境，并为观察气候变化的影响提供了合适的实验平台。这些外生硅藻群落的分布和多样性模式受苔藓生境的各种生物和非生物因素控制。本研究是有史以来首次尝试调查与印度喜马拉雅地区（IHR）的各种非生物环境变量相关的生苔硅藻。从喜马拉雅东部的尼奥拉河谷国家公园的23个不同地点收集了样本，并通过标准方法进行了分析。进行了双向指示剂物种分析（TWINSPAN）和聚类分析（CA）来对样品和生境进行分类，而直接典范对应分析（CCA）用于确定来自各种样品的生苔硅藻物种与非生物环境梯度之间的联系。在公园的23个地点的地面苔藓上发现了总共27个硅藻。CCA排序图显示，pH，电导率和相对湿度是影响硅藻多样性和分布的主要因素，但海拔和温度对物种分布没有影响。但是，有关Neora谷国家公园最丰富和最频繁的类群的平均气门长度的相关研究，即 在公园的23个地点的地面苔藓上发现了总共27个硅藻。CCA排序图显示，pH，电导率和相对湿度是影响硅藻多样性和分布的主要因素，但海拔和温度对物种分布没有影响。但是，有关Neora谷国家公园最丰富和最频繁的类群的平均气门长度的相关研究，即 在公园的23个地点的地面苔藓上发现了总共27个硅藻。CCA排序图显示，pH，电导率和相对湿度是影响硅藻多样性和分布的主要因素，但海拔和温度对物种分布没有影响。但是，有关Neora谷国家公园最丰富和最频繁的类群的平均气门长度的相关研究，即Eunotia paludosa，E。bigibba和Hantzschia amphioxys与诸如海拔，湿度，相对湿度和温度之类的环境变量有关，这表明存在明显的推断。这三个硅藻的平均气门长度在较低海拔的温暖和干燥气候条件下会降低。因此，这些可被视为观察任何气候变化的潜在指示物种。