Bioavailability of macro and micronutrients across global topsoils : Main drivers and global change impacts

Ochoa‐Hueso, Raúl and Delgado‐Baquerizo, Manuel and Risch, Anita C. and Ashton, Louise and Augustine, David and Bélanger, Nicolas and Bridgham, Scott and Britton, Andrea J. and Bruckman, Viktor J. and Camarero, J. Julio and Cornelissen, Gerard and Crawford, John A. and Dijkstra, Feike A. and Diochon, Amanda and Earl, Stevan and Edgerley, James and Epstein, Howard and Felton, Andrew and Fortier, Julien and Gagnon, Daniel and Greer, Ken and Griffiths, Hannah M and Halde, Caroline and Hanslin, Hans Martin and Harris, Lorna I. and Hartsock, Jeremy A. and Hendrickson, Paul and Hovstad, Knut Anders and Hu, Jia and Jani, Arun D. and Kent, Kelcy and Kerdraon‐Byrne, Deirdre and Khalsa, Sat Darshan S. and Lai, Derrick Y.F. and Lambert, France and LaMontagne, Jalene M. and Lavergne, Stéphanie and Lawrence, Beth A. and Littke, Kim and Leeper, Abigail C. and Licht, Mark A. and Liebig, Mark A. and Lynn, Joshua S. and Maclean, Janet E. and Martinsen, Vegard and McDaniel, Marshall D. and McIntosh, Anne C. S. and Miesel, Jessica R. and Miller, Jim and Mulvaney, Michael J. and Moreno, Gerardo and Newstead, Laura and Pakeman, Robin J. and Pergl, Jan and Pinno, Bradley D. and Piñeiro, Juan and Quigley, Kathleen and Radtke, Troy M. and Reed, Paul and Rolo, Víctor and Rudgers, Jennifer and Rutherford, P. Michael and Sayer, Emma J. and Serrano‐Grijalva, Lilia and Strack, Maria and Sukdeo, Nicole and Taylor, Andy F.S. and Truax, Benoit and Tsuji, Leonard J. S. and van Gestel, Natasja and Vaness, Brenda M. and Van Sundert, Kevin and Vítková, Michaela and Weigel, Robert and Wilton, Meaghan J. and Yano, Yuriko and Teen, Ewing and Bremer, Eric (2023) Bioavailability of macro and micronutrients across global topsoils : Main drivers and global change impacts. Global Biogeochemical Cycles, 37 (6): e2022GB007. ISSN 0886-6236

Abstract

Understanding the chemical composition of our planet's crust was one of the biggest questions of the 20th century. More than 100 years later, we are still far from understanding the global patterns in the bioavailability and spatial coupling of elements in topsoils worldwide, despite their importance for the productivity and functioning of terrestrial ecosystems. Here, we measured the bioavailability and coupling of thirteen macro‐ and micronutrients and phytotoxic elements in topsoils (3–8 cm) from a range of terrestrial ecosystems across all continents (∼10,000 observations) and in response to global change manipulations (∼5,000 observations). For this, we incubated between 1 and 4 pairs of anionic and cationic exchange membranes per site for a mean period of 53 days. The most bioavailable elements (Ca, Mg, and K) were also amongst the most abundant in the crust. Patterns of bioavailability were biome‐dependent and controlled by soil properties such as pH, organic matter content and texture, plant cover, and climate. However, global change simulations resulted in important alterations in the bioavailability of elements. Elements were highly coupled, and coupling was predictable by the atomic properties of elements, particularly mass, mass to charge ratio, and second ionization energy. Deviations from the predictable coupling‐atomic mass relationship were attributed to global change and agriculture. Our work illustrates the tight links between the bioavailability and coupling of topsoil elements and environmental context, human activities, and atomic properties of elements, thus deeply enhancing our integrated understanding of the biogeochemical connections that underlie the productivity and functioning of terrestrial ecosystems in a changing world.