Below-ground carbon input to soil is controlled by nutrient availability and fine root dynamics in loblolly pine
Article first published online: 30 APR 2002
Volume 154, Issue 2, pages 389–398, May 2002
How to Cite
King, J. S., Albaugh, T. J., Allen, H. L., Buford, M., Strain, B. R. and Dougherty, P. (2002), Below-ground carbon input to soil is controlled by nutrient availability and fine root dynamics in loblolly pine. New Phytologist, 154: 389–398. doi: 10.1046/j.1469-8137.2002.00393.x
- Issue published online: 30 APR 2002
- Article first published online: 30 APR 2002
- Received: 16 July 2001 Accepted: 14 December 2001
- seasonal phenology;
- fine root turnover;
- nutrient availability;
- water availability;
- loblolly pine;
- root dynamics
- • Availability of growth limiting resources may alter root dynamics in forest ecosystems, possibly affecting the land–atmosphere exchange of carbon. This was evaluated for a commercially important southern timber species by installing a factorial experiment of fertilization and irrigation treatments in an 8-yr-old loblolly pine (Pinus taeda) plantation.
- • After 3 yr of growth, production and turnover of fine, coarse and mycorrhizal root length was observed using minirhizotrons, and compared with stem growth and foliage development.
- • Fertilization increased net production of fine roots and mycorrhizal roots, but did not affect coarse roots. Fine roots had average lifespans of 166 d, coarse roots 294 d and mycorrhizal roots 507 d. Foliage growth rate peaked in late spring and declined over the remainder of the growing season, whereas fine roots experienced multiple growth flushes in the spring, summer and fall.
- • We conclude that increased nutrient availability might increase carbon input to soils through enhanced fine root turnover. However, this will depend on the extent to which mycorrhizal root formation is affected, as these mycorrhizal roots have much longer average lifespans than fine and coarse roots.