TY - JOUR

T1 - World distribution, diversity and endemism of aquatic macrophytes

AU - Murphy, Kevin

AU - Efremov, Andrey

AU - Davidson, Thomas A.

AU - Molina Navarro, Eugenio

AU - Fidanza, Karina

AU - Betiol, Tânia Camila Crivelari

AU - Chambers, Patricia

AU - Grimaldo, Julissa Tapia

AU - Martins, Sara Varandas

AU - Springuel, Irina

AU - Kennedy, Michael

AU - Mormul, Roger Paulo

AU - Dibble, Eric

AU - Hofstra, Deborah

AU - Lukács, Balázs András

AU - Gebler, Daniel

AU - Båstrup-Spohr, Lars

AU - Urrutia-Estrada, Jonathan

PY - 2019

Y1 - 2019

N2 - To test the hitherto generally-accepted hypothesis that most aquatic macrophytes have broad world distributions, we investigated the global distribution, diversity and endemism patterns of 3457 macrophyte species that occur in permanent, temporary or ephemeral inland freshwater and brackish waterbodies worldwide. At a resolution of 10 × 10° latitude x longitude, most macrophyte species were found to have narrow global distributions: 78% have ranges (measured using an approach broadly following the IUCN-defined concept “extent of occurrence”) that individually occupy <10% of the world area present within the six global ecozones which primarily provide habitat for macrophytes. We found evidence of non-linear relationships between latitude and macrophyte α- and γ-diversity, with diversity highest in sub-tropical to low tropical latitudes, declining slightly towards the Equator, and also declining strongly towards higher latitudes. Landscape aridity and, to a lesser extent, altitude and land area present per gridcell also influence macrophyte diversity and species assemblage worldwide. The Neotropics and Orient have the richest ecozone species-pools for macrophytes, depending on γ-diversity metric used. The region around Brasilia/Goiás (Brazil: gridcell 10–20 °S; 40–50 °W) is the richest global hotspot for macrophyte α-diversity (total species α-diversity, ST: 625 species/gridcell, 350 of them Neotropical endemics). In contrast, the Sahara/Arabian Deserts, and some Arctic areas, have the lowest macrophyte α-diversity (ST <20 species/gridcell). At ecozone scale, macrophyte species endemism is pronounced, though with a>5-fold difference between the most species-rich (Neotropics) and species-poor (Palaearctic) ecozones. Our findings strongly support the assertion that small-ranged species constitute most of Earth's species diversity.

AB - To test the hitherto generally-accepted hypothesis that most aquatic macrophytes have broad world distributions, we investigated the global distribution, diversity and endemism patterns of 3457 macrophyte species that occur in permanent, temporary or ephemeral inland freshwater and brackish waterbodies worldwide. At a resolution of 10 × 10° latitude x longitude, most macrophyte species were found to have narrow global distributions: 78% have ranges (measured using an approach broadly following the IUCN-defined concept “extent of occurrence”) that individually occupy <10% of the world area present within the six global ecozones which primarily provide habitat for macrophytes. We found evidence of non-linear relationships between latitude and macrophyte α- and γ-diversity, with diversity highest in sub-tropical to low tropical latitudes, declining slightly towards the Equator, and also declining strongly towards higher latitudes. Landscape aridity and, to a lesser extent, altitude and land area present per gridcell also influence macrophyte diversity and species assemblage worldwide. The Neotropics and Orient have the richest ecozone species-pools for macrophytes, depending on γ-diversity metric used. The region around Brasilia/Goiás (Brazil: gridcell 10–20 °S; 40–50 °W) is the richest global hotspot for macrophyte α-diversity (total species α-diversity, ST: 625 species/gridcell, 350 of them Neotropical endemics). In contrast, the Sahara/Arabian Deserts, and some Arctic areas, have the lowest macrophyte α-diversity (ST <20 species/gridcell). At ecozone scale, macrophyte species endemism is pronounced, though with a>5-fold difference between the most species-rich (Neotropics) and species-poor (Palaearctic) ecozones. Our findings strongly support the assertion that small-ranged species constitute most of Earth's species diversity.

KW - Aquatic plants

KW - Biodiversity hotspots

KW - Latitudinal diversity gradient

KW - Macroecology

KW - World ecozones

U2 - 10.1016/j.aquabot.2019.06.006

DO - 10.1016/j.aquabot.2019.06.006

M3 - Journal article

AN - SCOPUS:85068355301

VL - 158

JO - Aquatic Botany

JF - Aquatic Botany

SN - 0304-3770

M1 - 103127

ER -