Unexpected westward range shifts in European forest plants link to nitrogen deposition
Pieter Sanczuk, Kris Verheyen, Jonathan Lenoir, Florian Zellweger, Jonas J. Lembrechts, Francisco Rodríguez‐Sánchez, Lander Baeten, Markus Bernhardt‐Römermann, Karen De Pauw, Pieter Vangansbeke, Michael P. Perring, Imre Berki, Anne D. Bjorkman, Jörg Brunet, Markéta Chudomelová, Emiel De Lombaerde, Guillaume Decocq, Thomas Dirnböck, Tomasz Durak, Caroline Greiser, Radim Hédl, Thilo Heinken, Ute Jandt, Bogdan Jaroszewicz, Martin Kopecký, Dries Landuyt, Martin Macek, Frantíšek Máliš, Tobias Naaf, Thomas A. Nagel, Petr Petřík, Kamila Reczyńska, Wolfgang Schmidt, Tibor Standovár, Ingmar R. Staude, Krzysztof Świerkosz, Balázs Teleki, Thomas Vanneste, Ondřej Vild, Donald P. Waller, Pieter De Frenne
Abstract
Climate change is commonly assumed to induce species' range shifts toward the poles. Yet, other environmental changes may affect the geographical distribution of species in unexpected ways. Here, we quantify multidecadal shifts in the distribution of European forest plants and link these shifts to key drivers of forest biodiversity change: climate change, atmospheric deposition (nitrogen and sulfur), and forest canopy dynamics. Surprisingly, westward distribution shifts were 2.6 times more likely than northward ones. Not climate change, but nitrogen-mediated colonization events, possibly facilitated by the recovery from past acidifying deposition, best explain westward movements. Biodiversity redistribution patterns appear complex and are more likely driven by the interplay among several environmental changes than due to the exclusive effects of climate change alone.