Do species and functional groups differ in acquisition and use of C, N and water under varying atmospheric CO2 and N availability regimes? A field test with 16 grassland species
Article first published online: 21 DEC 2001
Volume 150, Issue 2, pages 435–448, May 2001
How to Cite
Reich, P. B., Tilman, D., Craine, J., Ellsworth, D., Tjoelker, M. G., Knops, J., Wedin, D., Naeem, S., Bahauddin, D., Goth, J., Bengtson, W. and Lee, T. D. (2001), Do species and functional groups differ in acquisition and use of C, N and water under varying atmospheric CO2 and N availability regimes? A field test with 16 grassland species. New Phytologist, 150: 435–448. doi: 10.1046/j.1469-8137.2001.00114.x
- Issue published online: 21 DEC 2001
- Article first published online: 21 DEC 2001
- Received: 11 September 2000 Accepted: 11 January 2000
- Functional groups;
- elevated carbon dioxide;
- N availability;
- grasses, forbs;
- • To evaluate whether functional groups have a similar response to global change, the responses to CO2 concentration and N availability of grassland species from several functional groups are reported here.
- • Sixteen perennial grassland species from four trait-based functional groups (C3 grasses, C4 grasses, non-leguminous forbs, legumes) were grown in field monocultures under ambient or elevated (560 µmol mol−1) CO2 using free-air CO2 enrichment (FACE), in low N (unamended field soil) or high N (field soil +4 g N m−2 years−1) treatments.
- • There were no CO2 × N interactions. Functional groups responded differently to CO2 and N in terms of biomass, tissue N concentration and soil solution N. Under elevated CO2, forbs, legumes and C3 grasses increased total biomass by 31%, 18%, and 9%, respectively, whereas biomass was reduced in C4-grass monocultures. Two of the four legume species increased biomass and total plant N pools under elevated CO2, probably due to stimulated N-fixation. Only one species markedly shifted the proportional distribution of below- vs aboveground biomass in response to CO2 or N.
- • Although functional groups varied in responses to CO2 and N, there was also substantial variation in responses among species within groups. These results suggest that current trait-based functional classifications might be useful, but not sufficient, for understanding plant and ecosystem responses to elevated CO2 and N availability.