Human activities shape global patterns of decomposition rates in rivers
Scott D. Tiegs, Krista A. Capps, David M. Costello, John P. Schmidt, Christopher J. Patrick, Jennifer J. Follstad Shah, Carri J. LeRoy, Vicenç Acuña, Ricardo Albariño, Daniel C. Allen, Cecília Alonso, Patricio Andino, Clay P. Arango, Jukka Aroviita, Marcus Vinícius Moreira Barbosa, Leon A. Barmuta, Colden V. Baxter, Brent J. Bellinger, Luz Boyero, Lyubov Bragina, Lee E. Brown, Andreas Bruder, Denise A. Bruesewitz, Francis J. Burdon, Marcos Callisto, Antonio Camacho, Cristina Canhoto, María M. Castillo, Éric Chauvet, Joanne E. Clapcott, Fanny Colas, J. Checo Colón-Gaud, Julien Cornut, Verónica Crespo‐Pérez, Wyatt F. Cross, Joseph M. Culp, Michaël Danger, Olivier Dangles, Elvira de Eyto, Alison M. Derry, Verónica Díaz Villanueva, Michael M. Douglas, Arturo Elosegi, Andrea C. Encalada, Sally A. Entrekin, Rodrigo Espinosa, Verónica Ferreira, Carmen Ferriol, Kyla M. Flanagan, Alexander S. Flecker, Tadeusz Fleituch, André Frainer, Nikolai Friberg, Paul C. Frost, Erica A. García, Liliana García-Lago, Pavel García, Mark O. Gessner, Sudeep D. Ghate, Darren P. Giling, Alan Gilmer, José Francisco Gonçalves, Rosario Karina Gonzales, Manuel A. S. Graça, Michael Grace, Natalie A. Griffiths, Hans‐Peter Grossart, François Guérold, Vladislav Gulis, Pablo E. Gutiérrez‐Fonseca, Luiz Ubiratan Hepp, Scott N. Higgins, Takuo Hishi, Joseph Huddart, John Hudson, Moss Imberger, Carlos Iñiguez‐Armijos, Mark W. Isken, Tomoya Iwata, David J. Janetski, Andrea E. Kirkwood, Aaron A. Koning, Sarian Kosten, Kevin A. Kuehn, Hjalmar Laudon, Peter R. Leavitt, Aurea Luiza Lemes da Silva, Shawn Leroux, Peter J. Lisi, Richard A. MacKenzie, Amy Marcarelli, Frank O. Masese, Peter B. McIntyre, Brendan G. McKie, Adriana O. Medeiros, Kristian Meissner, Marko Miliša, Shailendra Mishra, Yo Miyake, Ashley H. Moerke
Abstract
Rivers and streams contribute to global carbon cycling by decomposing immense quantities of terrestrial plant matter. However, decomposition rates are highly variable and large-scale patterns and drivers of this process remain poorly understood. Using a cellulose-based assay to reflect the primary constituent of plant detritus, we generated a predictive model (81% variance explained) for cellulose decomposition rates across 514 globally distributed streams. A large number of variables were important for predicting decomposition, highlighting the complexity of this process at the global scale. Predicted cellulose decomposition rates, when combined with genus-level litter quality attributes, explain published leaf litter decomposition rates with high accuracy (70% variance explained). Our global map provides estimates of rates across vast understudied areas of Earth and reveals rapid decomposition across continental-scale areas dominated by human activities.