Background In ichthyological publications from both Russia as a whole, and from the study region, lack of data indicating the actual results of observations in a specific place all result in publication of a generalised analysis. Although our publications contain such data, they are, however, not convenient for users performing global analysis. The main purpose of publishing a database is to make our data available in the global biodiversity system to a wide range of users. Dataset represents a significant addition to the distribution of species in this area. The data can be used to analyse future changes in ichthyofauna, as well as to help the authorities to manage their territory more efficiently. This publication describes a dataset that contains information on fish encounters in the Upper Don basin and the middle Volga (centre of the European part of Russia) over a 30-year period (1990-2020). The dataset contains information on 6400 occurrences of 394341 specimens of 56 species, 99.9% of specimens being identified to the species level. A total of 883 sites were studied, of which 253 were in lentic biotopes (lakes - 121, ponds - 123, backwater - 5, reservoir - 3, pit - 1), 630 were in lotic (rivers - 628, stream - 1, channel - 1). One collecting site has an average of 7.2 species (from 1-21 species per location). Only those species that form self-reproducing populations are given. The dataset is a compilation of data from several working author groups. All observations have precise geo-referencing with the names of water bodies (rivers, lakes etc.). New information All presented data are published in the form of a database for the first time. Some data form the basis of previously-published works (3998 observations, 62%) and some are published for the first time (2402 observations, 38%). A large amount of data comes from small water bodies that have been neglected by previous researchers.

中文翻译：

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伏尔加河中部和顿河上游地区的鱼类出现情况（俄罗斯）


背景 在整个俄罗斯和研究区域的鱼类学出版物中，缺乏表明特定地点实际观测结果的数据都导致发表了概括性分析。尽管我们的出版物包含此类数据，但它们不方便用户进行全局分析。发布数据库的主要目的是让我们的数据在全球生物多样性系统中可供广泛的用户使用。数据集代表了该地区物种分布的显着增加。这些数据可用于分析鱼类动物群的未来变化，并帮助当局更有效地管理其领土。本出版物描述了一个数据集，其中包含 30 年期间（1990-2020 年）顿河上游盆地和伏尔加河中部（俄罗斯欧洲部分中心）鱼类遭遇情况的信息。该数据集包含 56 个物种 394341 个标本 6400 次出现的信息，99.9% 的标本已被识别到物种级别。总共研究了 883 个地点，其中 253 个位于静水生境（湖泊 - 121 个，池塘 - 123 个，回水 - 5 个，水库 - 3 个，坑 - 1 个），630 个位于激流区（河流 - 628 个，溪流 - 1 个，通道 - 1).一个采集点平均有 7.2 个物种（每个地点 1-21 个物种）。仅给出那些形成自我繁殖种群的物种。该数据集是来自多个工作作者组的数据的汇编。所有观测结果都有精确的地理参考和水体名称（河流、湖泊等）。新信息 所有呈现的数据首次以数据库的形式发布。 有些数据构成了先前发表的作品的基础（3998 个观测值，62%），有些数据是首次发表（2402 个观测值，38%）。大量数据来自先前研究人员忽视的小型水体。