Global impoverishment of natural vegetation revealed by dark diversity
Meelis Pärtel, Riin Tamme, Carlos P. Carmona, Kersti Riibak, Mari Moora, Jonathan Bennett, Alessandro Chiarucci, Milan Chytrý, Francesco de Bello, Ove Eriksson, Susan Harrison, Rob J. Lewis, Angela T. Moles, Maarja Öpik, Jodi N. Price, Vistorina Amputu, Diana Askarizadeh, Zohreh Atashgahi, Isabelle Aubin, Francisco M. Azcárate, Matthew D. Barrett, Maral Bashirzadeh, Zoltán Bátori, Natalie Beenaerts, Kolja Bergholz, Kristine Birkeli, Idoia Biurrun, José M. Blanco‐Moreno, Kathryn J. Bloodworth, Laura Boisvert‐Marsh, Bazartseren Boldgiv, Pedro H. S. Brancalion, Francis Q. Brearley, Charlotte Brown, C. Guillermo Bueno, Gabriella Buffa, James F. Cahill, Juan Antonio Campos, Giacomo Cangelmi, Michele Carbognani, Christopher Carcaillet, Bruno Enrico Leone Cerabolini, Richard Chevalier, Jan Clavel, José Miguel Costa, Sara A. O. Cousins, Jan Čuda, Mariana Dairel, Michele Dalle Fratte, Alena Danilova, John Davison, Balázs Déak, Silvia Del Vecchio, Iwona Dembicz, Jürgen Dengler, Jiří Doležal, Xavier Domene, Miroslav Dvorský, Hamid Ejtehadi, Lucas Enrico, Dmitrii Epikhin, Anu Eskelinen, Franz Essl, Gaohua Fan, Edy Fantinato, Fatih Fazlioglu, Eduardo Fernández‐Pascual, Arianna Ferrara, Alessandra Fidélis, Markus Fischer, Maren Flagmeier, T’ai G. W. Forte, Lauchlan H. Fraser, Junichi Fujinuma, Fernando Forster Furquim, Berle Garris, Heath W. Garris, Melisa A. Giorgis, Gianpietro Giusso del Galdo, Ana González‐Robles, Megan Good, Moisès Guardiola, Riccardo Guarino, Irene Guerrero, Joannès Guillemot, Behlül Güler, Yinjie Guo, Stef Haesen, Martin Hejda, Rúben Heleno, Toke T. Høye, Richard Hrivnák, Yingxin Huang, John T. Hunter, Dmytro Iakushenko, Ricardo Ibáñez, Nele Ingerpuu, Severin D. H. Irl, Eva Janíková, Florian Jansen
Abstract
Anthropogenic biodiversity decline threatens the functioning of ecosystems and the many benefits they provide to humanity1. As well as causing species losses in directly affected locations, human influence might also reduce biodiversity in relatively unmodified vegetation if far-reaching anthropogenic effects trigger local extinctions and hinder recolonization. Here we show that local plant diversity is globally negatively related to the level of anthropogenic activity in the surrounding region. Impoverishment of natural vegetation was evident only when we considered community completeness: the proportion of all suitable species in the region that are present at a site. To estimate community completeness, we compared the number of recorded species with the dark diversity—ecologically suitable species that are absent from a site but present in the surrounding region2. In the sampled regions with a minimal human footprint index, an average of 35% of suitable plant species were present locally, compared with less than 20% in highly affected regions. Besides having the potential to uncover overlooked threats to biodiversity, dark diversity also provides guidance for nature conservation. Species in the dark diversity remain regionally present, and their local populations might be restored through measures that improve connectivity between natural vegetation fragments and reduce threats to population persistence. A comparison of alpha diversity (number of plant species) and dark diversity (species that are currently absent from a site despite being ecologically suitable) demonstrates the negative effects of regional-scale anthropogenic activity on plant diversity.