Canadian journal of forest research. 2007 Jan., v. 37, no. 1, p. 93-102.
NALT Subjects:
Pinus resinosa dry matter partitioning carbon sequestration carbon forest trees tree growth forest growth forest stands age structure environmental factors stand management hardwood coniferous forests allometry roots shoots Michigan
Other Subjects:
root-shoot ratio
Issue Date:
Jan-2007
Abstract:
Carbon (C) allocation to the perennial coarse-root system of trees contributes to ecosystem C sequestration through formation of long-lived live wood biomass and, following senescence, by providing a large source of nutrient-poor detrital C. Our understanding of the controls on C allocation to coarse-root growth is rudimentary, but it has important implications for projecting belowground net primary production responses to global change. Age-related changes in C allocation to coarse roots represent a critical uncertainty for modeling landscape-scale C storage and cycling. We used a 55 year chronosequence approach with complete above- and below-ground harvests to assess the effects of stand development on biomass partitioning in red pine (Pinus resinosa Ait.), a commercially important pine species. Averaged within site, individual-tree root/shoot ratios were dynamic across stand development, changing from 0.17 at 2-, 3-, and 5-year-old sites, to 0.80 at the 8-year-old site, to 0.29 at the 55-year-old site. The results of our study suggest that a current research challenge is to determine the generality of patterns of root-shoot biomass partitioning through stand development for both coniferous and hardwood forest types, and to document how these patterns change as a function of stand age, tree size, environment, and management.