Heino J. auteur aut IRD Melo A. S. auteur aut IRD Bini L. M. auteur aut IRD Altermatt F. auteur aut IRD Al-Shami S. A. auteur aut IRD Angeler D. G. auteur aut IRD Bonada N. auteur aut IRD Brand C. auteur aut IRD Callisto M. auteur aut IRD Cottenie K. auteur aut IRD Dangles Olivier auteur aut IRD Dudgeon D. auteur aut IRD Encalada A. auteur aut IRD Gothe E. auteur aut IRD Gronroos M. auteur aut IRD Hamada N. auteur aut IRD Jacobsen D. auteur aut IRD Landeiro V. L. auteur aut IRD Ligeiro R. auteur aut IRD Martins R. T. auteur aut IRD Miserendino M. L. auteur aut IRD Md Rawi C. S. auteur aut IRD Rodrigues M. E. auteur aut IRD Roque F. D. auteur aut IRD Sandin L. auteur aut IRD Schmera D. auteur aut IRD Sgarbi L. F. auteur aut IRD Simaika J. P. auteur aut IRD Siqueira T. auteur aut IRD Thompson R. M. auteur aut IRD Townsend C. R. auteur aut IRD text journalArticle eng text/pdf born digital access The hypotheses that beta diversity should increase with decreasing latitude and increase with spatial extent of a region have rarely been tested based on a comparative analysis of multiple datasets, and no such study has focused on stream insects. We first assessed how well variability in beta diversity of stream insect metacommunities is predicted by insect group, latitude, spatial extent, altitudinal range, and dataset properties across multiple drainage basins throughout the world. Second, we assessed the relative roles of environmental and spatial factors in driving variation in assemblage composition within each drainage basin. Our analyses were based on a dataset of 95 stream insect metacommunities from 31 drainage basins distributed around the world. We used dissimilarity-based indices to quantify beta diversity for each metacommunity and, subsequently, regressed beta diversity on insect group, latitude, spatial extent, altitudinal range, and dataset properties (e.g., number of sites and percentage of presences). Within each metacommunity, we used a combination of spatial eigenfunction analyses and partial redundancy analysis to partition variation in assemblage structure into environmental, shared, spatial, and unexplained fractions. We found that dataset properties were more important predictors of beta diversity than ecological and geographical factors across multiple drainage basins. In the within-basin analyses, environmental and spatial variables were generally poor predictors of variation in assemblage composition. Our results revealed deviation from general biodiversity patterns because beta diversity did not show the expected decreasing trend with latitude. Our results also call for reconsideration of just how predictable stream assemblages are along ecological gradients, with implications for environmental assessment and conservation decisions. Our findings may also be applicable to other dynamic systems where predictability is low. specialized Altitude range comparative analysis environmental filtering insects latitude spatial extent variance partitioning AMERIQUE EUROPE 082 5 6 1235-1248 2015 2045-7758 https://www.documentation.ird.fr/hor/fdi:010064028 10.1002/ece3.1439 2045-7758 [F B010064028] https://www.documentation.ird.fr/hor/fdi:010064028 https://www.documentation.ird.fr/intranet/publi/2015/04/010064028.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2015-05-04 2017-08-23 fdi:010064028 fre