Quantity of Standing Litter: A Driving Factor of Root Dynamics
Current understanding of carbon cycling in terrestrial ecosystem views “quantity” of litter input as a parameter determining the size of soil C pools and soil respired CO2: quantity of litter input is not considered a driving factor affecting the patterns of terrestrial ecosystem processes. Emma J. Sayer and collaborators demonstrated that this may not be the case! With a neat and elegant, for its simplicity, manipulation experiment, Sayer et al. (this issue) showed how increasing input of leaf litter affects the patterns of root distribution along the soil profile, in a relatively nutrient rich tropical soil. In their study, roots responded rapidly to changes in fresh leaf litter input and appeared to closely follow the patterns of litter decomposition. Until this study, root exploitation of standing litter was seen solely as an adaptation to nutrient shortage in the mineral soil. Feedback processes between leaf litterfall, decomposition and root dynamics are envisaged. With global climate change likely to alter plant productivity and litterfall, similar feedbacks, if confirmed, will need to be included in terrestrial ecosystem C modelling.
Keywordslitterfall root growth tropical soils
Unable to display preview. Download preview PDF.
- Berg, B 1987Dynamics of nitrogen (15N) in decomposing Scots pine (Pinus sylvestris) needle litter. Long-term decomposition in a Scots pine forest. VICan. J. Bot.6615391546Google Scholar
- Dormaar, J F 1990Effect of active roots on the decomposition of soil organic materialsBiol. Fertil. Soils10121126Google Scholar
- Hoosbeek, M R, Lukac, M, Dam, D, Godbold, D L, Velthorst, E J, Biondi, F A, Peressotti, A, Cotrufo, M F, Angelis, P, Scarascia-Mugnozza, G 2004More new carbon in the mineral soil of a poplar plantation under free air carbon enrichment (FACE): Cause of increased priming effect?Glob. Biogeochem. Cycle1810411047Google Scholar
- Joslin, J D, Henderson, G S 1987Organic matter and nutrients associated with fine root turnover in a white oak standForest Sci.33330346Google Scholar
- Sayer, EJ, Tanner , EVJ, Cheesman, AW 2006 Increased litterfall changes fine root distribution in a moist tropical forestPlant Soil281513Google Scholar
- Wullschleger, S D, Norby, R J, Gunderson, C A 1997Forest trees and their response to atmospheric CO2 enrichment. A compilation of resultsAllen, L H JKirkham, M BOlszyk, D MWhitman, C E eds. Advances in Carbon Dioxide Effects ResearchAmerican Society of Agronomy Special PublicationMadison, WI79100Google Scholar