Influence of past and current factors on the beta diversity of coastal lagoon fish communities in South America

Aim: We aimed to assess the relative influence of past (Quaternary paleodrainage characteristics) and current factors on the beta diversity of freshwater fishes in coastal lagoons and explore the main processes involved.

Location: Atlantic coast of South America. Taxon: Fishes (173 species)

Methods: We built a dataset of species occurrence in 129 lagoons across eight freshwater ecoregions of the world (FEOWs) located between latitudes 0° and 36° and calculated beta diversity (βjac) and its turnover (βjtu) and nestedness (βjne) components. We used a partial Mantel test and multiple regressions on distance matrices to evaluate the importance of past and current factors, and of geographical distance in determining beta diversity. Past variables were those representing the historical freshwater habitat during the last glacial maximum (LGM), and contemporary variables were those related to current habitat.

Results: We found high values of βjac within the FEOWs, with βjtu prevailing ...

研究目的：本研究旨在评估第四纪古水系特征（Quaternary paleodrainage characteristics）与当代因子对沿海潟湖淡水鱼类β多样性的相对影响，并探究其背后的核心调控过程。
研究区域：南美洲大西洋沿岸。
研究类群：鱼类（共173种）。
研究方法：本研究构建了分布于纬度0°至36°区间内的8个全球淡水生态区（Freshwater Ecoregions of the World, FEOWs）中129个潟湖的物种出现数据集，并计算了贾卡德β多样性（βjac）及其周转组分（βjtu）与嵌套组分（βjne）。本研究采用偏曼特尔检验与距离矩阵多元回归分析方法，评估过去因子、当代因子及地理距离对β多样性的贡献程度。其中，过去变量指代末次盛冰期（Last Glacial Maximum, LGM）时期的历史淡水生境特征，当代变量则与当前生境相关。
研究结果：本研究发现全球淡水生态区（FEOWs）内的βjac值较高，且以βjtu占主导地位……