Global Patterns and Controls of Nutrient Immobilization on Decomposing Cellulose in Riverine Ecosystems

Autor: David M. Costello, Scott D. Tiegs, Luz Boyero, Cristina Canhoto, Krista A. Capps, Michael Danger, Paul C. Frost, Mark O. Gessner, Natalie A. Griffiths, Halvor M. Halvorson, Kevin A. Kuehn, Amy M. Marcarelli, Todd V. Royer, Devan M. Mathie, Ricardo J. Albariño, Clay P. Arango, Jukka Aroviita, Colden V. Baxter, Brent J. Bellinger, Andreas Bruder, Francis J. Burdon, Marcos Callisto, Antonio Camacho, Fanny Colas, Julien Cornut, Verónica Crespo‐Pérez, Wyatt F. Cross, Alison M. Derry, Michael M. Douglas, Arturo Elosegi, Elvira de Eyto, Verónica Ferreira, Carmen Ferriol, Tadeusz Fleituch, Jennifer J. Follstad Shah, André Frainer, Erica A. Garcia, Liliana García, Pavel E. García, Darren P. Giling, R. Karina Gonzales‐Pomar, Manuel A. S. Graça, Hans‐Peter Grossart, François Guérold, Luiz U. Hepp, Scott N. Higgins, Takuo Hishi, Carlos Iñiguez‐Armijos, Tomoya Iwata, Andrea E. Kirkwood, Aaron A. Koning, Sarian Kosten, Hjalmar Laudon, Peter R. Leavitt, Aurea L. Lemes da Silva, Shawn J. Leroux, Carri J. LeRoy, Peter J. Lisi, Frank O. Masese, Peter B. McIntyre, Brendan G. McKie, Adriana O. Medeiros, Marko Miliša, Yo Miyake, Robert J. Mooney, Timo Muotka, Jorge Nimptsch, Riku Paavola, Isabel Pardo, Ivan Y. Parnikoza, Christopher J. Patrick, Edwin T. H. M. Peeters, Jesus Pozo, Brian Reid, John S. Richardson, José Rincón, Geta Risnoveanu, Christopher T. Robinson, Anna C. Santamans, Gelas M. Simiyu, Agnija Skuja, Jerzy Smykla, Ryan A. Sponseller, Franco Teixeira‐de Mello, Sirje Vilbaste, Verónica D. Villanueva, Jackson R. Webster, Stefan Woelfl, Marguerite A. Xenopoulos, Adam G. Yates, Catherine M. Yule, Yixin Zhang, Jacob A. Zwart
Přispěvatelé: Suomen ympäristökeskus, The Finnish Environment Institute
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Global Biogeochemical Cycles, 36(3)
Global Biogeochemical Cycles
Global Biogeochemical Cycles 36 (2022) 3
Global Biogeochemical Cycles, 36, 3, pp. 1-15
Global Biogeochemical Cycles, 36, 1-15
ISSN: 0886-6236
Popis: Microbes play a critical role in plant litter decomposition and influence the fate of carbon in rivers and riparian zones. When decomposing low-nutrient plant litter, microbes acquire nitrogen (N) and phosphorus (P) from the environment (i.e., nutrient immobilization), and this process is potentially sensitive to nutrient loading and changing climate. Nonetheless, environmental controls on immobilization are poorly understood because rates are also influenced by plant litter chemistry, which is coupled to the same environmental factors. Here we used a standardized, low-nutrient organic matter substrate (cotton strips) to quantify nutrient immobilization at 100 paired stream and riparian sites representing 11 biomes worldwide. Immobilization rates varied by three orders of magnitude, were greater in rivers than riparian zones, and were strongly correlated to decomposition rates. In rivers, P immobilization rates were controlled by surface water phosphate concentrations, but N immobilization rates were not related to inorganic N. The N:P of immobilized nutrients was tightly constrained to a molar ratio of 10:1 despite wide variation in surface water N:P. Immobilization rates were temperature-dependent in riparian zones but not related to temperature in rivers. However, in rivers nutrient supply ultimately controlled whether microbes could achieve the maximum expected decomposition rate at a given temperature. Collectively, we demonstrated that exogenous nutrient supply and immobilization are critical control points for decomposition of organic matter. Key Points • Nitrogen (N) and phosphorus (P) immobilization was measured on organic matter (cotton) in 100 rivers and riparian zones representing 11 biomes • Elevated temperature in riparian zones and phosphate in rivers increased immobilization, and consequently accelerated decomposition • N and P immobilization was strongly linked by microbial stoichiometry despite widely varied surface-water nutrient ratios Plain Language Summary Bacteria and fungi contribute to the breakdown of leaf litter in rivers and floodplains. To break down leaf litter, these microbes need the nutrients nitrogen and phosphorus (P), and microbes can get nutrients either from the leaf litter itself or from the environment. Most leaf litter has low nutrient content and microbes must rely on the environment to supply nutrients. We studied microbial nutrient uptake from the environment during litter breakdown to determine whether it varies predictably across the globe and how it is influenced by changing climate and nutrient pollution. In 100 rivers and floodplains in 11 of Earth's major biomes we placed small strips of cotton as stand-ins for leaf litter. Nutrient uptake was consistently greater on cotton strips that were submerged in the river compared to cotton on the floodplain. For microbes in the river, nutrient uptake was faster in instances where there was more P in the water. For microbes in the floodplain, nutrient uptake was faster where temperatures were warmer. Faster nutrient uptake by microbes was linked with faster cotton breakdown in rivers and floodplains. Our study shows that climate change and nutrient pollution can alter the activity of microbes in rivers and floodplains.
Databáze: OpenAIRE