TY - JOUR T1 - Plant nitrogen and phosphorus limitation in 98 North American grassland soils JF - Plant and Soil Y1 - 2010 A1 - Craine, J.M. A1 - Jackson, R.D. KW - Colimitation KW - Grasslands KW - nitrogen KW - Phosphorus KW - stoichiometry AB -

The availability of nutrients is a critical determinant of ecological dynamics in grasslands, but the relationships between soil resource availability and nutrient limitation across ecosystems are not clear. To better understand how soil nutrient availability determines nutrient limitation in vegetation, we grew the same species of grass (Schizachyrium scoparium) in 98 North American grassland soils and fertilized them factorially with nitrogen (N) and phosphorus (P). On average adding N, P, and the two nutrients together increased biomass relative to unfertilized plants by 81%, 22%, and 131%, respectively. Plants grown on low-P soils were not primarily limited by P. Instead, these plants were colimited by N and P, while plants grown on high-P soils were primarily limited by N and only secondarily limited by P. Limitation was not predicted by total soil N. The preponderance of colimitation between N and P on low-P soils suggests that low P availability alters the N cycle to constrain supplies to plants such that N and P are made available in proportion to their demand by plants.

VL - 334 UR - https://link.springer.com/article/10.1007%2Fs11104-009-0237-1 ER -