Latitude dictates plant diversity effects on instream decomposition
Luz Boyero, Javier Pérez, Naiara López‐Rojo, Alan M. Tonin, Francisco Correa‐Araneda, Richard G. Pearson, Jaime Bosch, Ricardo Albariño, Sankarappan Anbalagan, Leon A. Barmuta, Leah Beesley, Francis J. Burdon, Adriano Caliman, Marcos Callisto, Ian C. Campbell, Bradley J. Cardinale, J. Jesús Casas, Ana M. Chará‐Serna, Szymon Ciapała, Éric Chauvet, J. Checo Colón-Gaud, Aydeé Cornejo, Aaron M. Davis, Monika Degebrodt, Emerson S. Dias, María Elisa Díaz, Michael M. Douglas, Arturo Elosegi, Andrea C. Encalada, Elvira de Eyto, Ricardo Figueroa, Alexander S. Flecker, Tadeusz Fleituch, André Frainer, Juliana França, Erica A. García, Gabriela García, Pavel García, Mark O. Gessner, Paul S. Giller, Jesús E. Gómez, Sergio Gómez, José Francisco Gonçalves, Manuel A. S. Graça, Robert O. Hall, Neusa Hamada, Luiz Ubiratan Hepp, Cang Hui, Daichi Imazawa, Tomoya Iwata, S. A. Edson, Samuel Kariuki, Andrea Landeira‐Dabarca, María Leal, Kaisa Lehosmaa, Charles M’Erimba, L. C. Marchant, Renato Tavares Martins, Frank O. Masese, Megan R. Camden, Brendan G. McKie, Adriana O. Medeiros, Jen A. Middleton, Timo Muotka, Junjiro N. Negishi, Jesús Pozo, Alonso Ramírez, Renan de Souza Rezende, John S. Richardson, José Rincón, J. L. Rubio, Claudia Serrano, Angela R. Shaffer, Fran Sheldon, Christopher M. Swan, Nathalie Sia Doumbou Tenkiano, Scott D. Tiegs, Janine Rodulfo Tolod, Michael Vernasky, Anne Watson, Mourine J. Yegon, Catherine M. Yule
Abstract
Running waters contribute substantially to global carbon fluxes through decomposition of terrestrial plant litter by aquatic microorganisms and detritivores. Diversity of this litter may influence instream decomposition globally in ways that are not yet understood. We investigated latitudinal differences in decomposition of litter mixtures of low and high functional diversity in 40 streams on 6 continents and spanning 113° of latitude. Despite important variability in our dataset, we found latitudinal differences in the effect of litter functional diversity on decomposition, which we explained as evolutionary adaptations of litter-consuming detritivores to resource availability. Specifically, a balanced diet effect appears to operate at lower latitudes versus a resource concentration effect at higher latitudes. The latitudinal pattern indicates that loss of plant functional diversity will have different consequences on carbon fluxes across the globe, with greater repercussions likely at low latitudes.