eDNA metabarcoding to monitor fish communities in a large river floodplain

This dataset contains raw and processed environmental DNA (eDNA)
metabarcoding and electrofishing data used to compare fish community
composition across the floodplain of Lake St. Pierre, the largest
floodplain habitat along the St. Lawrence River (Québec, Canada). The
study aimed to evaluate the effectiveness of eDNA metabarcoding relative
to traditional electrofishing for biomonitoring fish diversity in a
hydrologically dynamic and heterogeneous floodplain system. Sampling was
conducted across multiple floodplain sectors encompassing a gradient of
land uses, from natural wetlands to annual crop agriculture. The dataset
includes: (1) raw Illumina sequence files from eDNA samples, (2) processed
read tables generated following stringent bioinformatic filtering and
taxonomic assignment, (3) site-level electrofishing catch data including
species identity, abundance, and biomass, and (4) associated environmental
metadata (e.g., sector, land use classification, geographic coordinates).
These data underpin analyses demonstrating that eDNA metabarcoding detects
a broader range of species than electrofishing, while both methods
reliably capture the most abundant taxa. The dataset further supports
findings that eDNA-derived fish community composition is more strongly
associated with spatial structuring across floodplain sectors than with
variation in land use. The deposited files can be reused to explore
species-specific detection patterns, method congruence, and spatial
drivers of fish diversity in large river floodplains, and to inform future
methodological comparisons in freshwater biomonitoring.

本数据集涵盖用于对比圣劳伦斯河（加拿大魁北克省）最大洪泛平原栖息地——圣皮埃尔湖洪泛区鱼类群落组成的原始与预处理环境DNA（eDNA）宏条形码（metabarcoding）及电渔法数据。本研究旨在评估eDNA宏条形码技术相较于传统电渔法，在水文动态且异质性强的洪泛平原系统中开展鱼类多样性生物监测的有效性。采样覆盖多个洪泛平原片区，涵盖从自然湿地到一年生作物农业用地的土地利用梯度。本数据集包含以下内容：(1) 环境DNA样本的原始Illumina测序文件；(2) 经严格生物信息学过滤与物种分类注释后生成的预处理读长表；(3) 站点级电渔法捕获数据，包含物种鉴定结果、丰度与生物量；(4) 配套环境元数据（如片区信息、土地利用分类、地理坐标）。上述数据支撑的分析结果表明，eDNA宏条形码技术可检测到比电渔法更广泛的物种类群，且两种方法均能可靠捕获丰度最高的类群。本数据集进一步验证了相关研究发现：基于eDNA的鱼类群落组成与洪泛平原片区的空间结构关联性，远强于其与土地利用变化的关联性。本数据集所收录的文件可被重复利用，用于探究大型河流洪泛区的物种特异性检测模式、两种监测方法的一致性，以及鱼类多样性的空间驱动因子，同时可为未来淡水生物监测的方法学对比研究提供参考。