Extensive belowground carbon storage supports roots and mycorrhizae in regenerating scrub oaks.
Portions of a regenerating scrub oak ecosystem were enclosed in open-top chambers and exposed to elevated CO2. The distinct 13C signal of the supplemental CO2 was used to trace the rate of C integration into various ecosystem components. Oak foliage, stems, roots and ectomycorrhizae were sampled ove...
| Main Authors: | , , |
|---|---|
| Format: | |
| Language: | English |
| Published: |
2002
|
| Online Access: | http://ezproxy.villanova.edu/login?url=https://digital.library.villanova.edu/Item/vudl:177987 |
| Summary: | Portions of a regenerating scrub oak ecosystem
were enclosed in open-top chambers and exposed to
elevated CO2. The distinct 13C signal of the supplemental
CO2 was used to trace the rate of C integration into
various ecosystem components. Oak foliage, stems, roots
and ectomycorrhizae were sampled over 3 years and
were analyzed for 13C composition. The aboveground
tissue 13C equilibrated to the novel 13C signal in the first
season, while the belowground components displayed
extremely slow integration of the new C. Roots taken
from ingrowth cores showed that 33% of the C in newly
formed roots originated from a source other than recent
photosynthesis inside the chamber. In this highly fireprone
system, the oaks re-establish primarily by resprouting
from large rhizomes. Remobilization from belowground
C stores may support fine roots and mycorrhizae
for several years into stand re-establishment and,
therefore, may explain why belowground tissues contain
less of the new photosynthate than expected. Though it
has been shown that long-term cycles of C storage are
theoretically advantageous for plants in systems with frequent
and severe disturbances, such patterns have not
been previously examined in wild systems. |
|---|