Grassland productivity limited by multiple nutrients

• Published in: Nature plants Vol. 1; no. 7; p. 15080
• Main Authors: Fay, Philip A., Prober, Suzanne M., Harpole, W. Stanley, Knops, Johannes M. H., Bakker, Jonathan D., Borer, Elizabeth T., Lind, Eric M., MacDougall, Andrew S., Seabloom, Eric W., Wragg, Peter D., Adler, Peter B., Blumenthal, Dana M., Buckley, Yvonne M., Chu, Chengjin, Cleland, Elsa E., Collins, Scott L., Davies, Kendi F., Du, Guozhen, Feng, Xiaohui, Firn, Jennifer, Gruner, Daniel S., Hagenah, Nicole, Hautier, Yann, Heckman, Robert W., Jin, Virginia L., Kirkman, Kevin P., Klein, Julia, Ladwig, Laura M., Li, Qi, McCulley, Rebecca L., Melbourne, Brett A., Mitchell, Charles E., Moore, Joslin L., Morgan, John W., Risch, Anita C., Schütz, Martin, Stevens, Carly J., Wedin, David A., Yang, Louie H.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 06.07.2015; Nature Publishing Group
• Subjects: 631/449/2668; 704/158/2445; 704/158/2453; Biomedical and Life Sciences; Continents; Ecosystem assessment; Ecosystems; Grasslands; Life Sciences; Micronutrients; Net Primary Productivity; Nitrogen; Nutrient availability; Nutrient enrichment; Nutrients; Phosphorus; Plant Sciences; Potassium; Primary production; Productivity; Terrestrial ecosystems
• ISSN: 2055-0278; 2055-0278
• DOI: 10.1038/nplants.2015.80

Terrestrial ecosystem productivity is widely accepted to be nutrient limited 1 . Although nitrogen (N) is deemed a key determinant of aboveground net primary production (ANPP) 2 , 3 , the prevalence of co-limitation by N and phosphorus (P) is increasingly recognized 4 – 8 . However, the extent to which terrestrial productivity is co-limited by nutrients other than N and P has remained unclear. Here, we report results from a standardized factorial nutrient addition experiment, in which we added N, P and potassium (K) combined with a selection of micronutrients (K + μ ), alone or in concert, to 42 grassland sites spanning five continents, and monitored ANPP. Nutrient availability limited productivity at 31 of the 42 grassland sites. And pairwise combinations of N, P, and K + μ co-limited ANPP at 29 of the sites. Nitrogen limitation peaked in cool, high latitude sites. Our findings highlight the importance of less studied nutrients, such as K and micronutrients, for grassland productivity, and point to significant variations in the type and degree of nutrient limitation. We suggest that multiple-nutrient constraints must be considered when assessing the ecosystem-scale consequences of nutrient enrichment. Terrestrial ecosystem productivity is widely accepted to be nutrient limited. A series of standardized nutrient addition experiments, carried out on grasslands on five continents, suggests aboveground grassland productivity is commonly limited by multiple nutrients, including potassium and micronutrients.