Nutrients cause grassland biomass to outpaceherbivory
Date
2020-11
Authors
Borer, Elizabeth
Harpole, W. Stanley
Adler, Peter
Arnillas, Carlos Alberto
Bugalho, Miguel
Cadotte, Marc
Caldeira, Maria
Campana, Sofia
Dickman, Christopher
Dickson, Timothy
Journal Title
Journal ISSN
Volume Title
Publisher
Springer Nature
Abstract
Human activities are transforming grassland biomass via changing climate, elemental nutrients, and herbivory. Theory predicts that food-limited herbivores will consume any additional biomass stimulated by nutrient inputs (‘consumer-controlled’). Alternatively,nutrient supply is predicted to increase biomass where herbivores alter community com-position or are limited by factors other than food (‘resource-controlled’). Using an experiment replicated in 58 grasslands spanning six continents, we show that nutrient addition and vertebrate herbivore exclusion each caused sustained increases in above ground live biomass over a decade, but consumer control was weak. However, at sites with high vertebrate grazing intensity or domestic livestock, herbivores consumed the additional fertilization-induced biomass, supporting the consumer-controlled prediction. Herbivores most effectively reduced the additional live biomass at sites with low precipitation or high ambient soil nitrogen. Overall, these experimental results suggest that grassland biomass will outstrip wild herbivore control as human activities increase elemental nutrient supply, with widespread consequences for grazing and fire risk.
Description
Keywords
grassland biomass, herbivores, nutrients, herbivore control, Biology
Citation
Borer, E.T., Harpole, W.S., Adler, P.B., <i>et al.</i> (2020). Nutrients cause grassland biomass to outpace herbivory. Nature Communications, 11(6036).