Plants, generally
and as individual species, are among the important controls
on nutrient cycling in terrestrial ecosystems. An understanding
of the effects of plant species on nutrient cycling should
improve our ability to predict ecosystem response to
perturbations such as climate change or invasion by exotic
species. Such knowledge may also aid in guiding ecosystem
management and restoration of late-successional composition
and function of forests in addition to structural characteristics.
Old-growth forests of the Pacific Northwest provide a
unique opportunity to examine tree species effects on
soils in a wide range of ecosystems that developed with
minimal anthropogenic disturbance.
The
overall objective of this research is to explore the
relationship of forest ecosystem structure and composition
with function. In particular, this project addresses
the following questions:
•
How
do individual tree species differ in their influence
on soils of mixed old-growth forests of the Oregon
Coast Range?
•
How important are tree species effects across a broad geographic area?
•
What are some potential mechanisms by which tree species influence soil properties
and nutrient cycles?
In an observational study, soil and foliar properties
are being quantified and compared among tree species within and across mixed
old-growth
stands. A manipulative study tests the leaf-litter leachate mechanism of
tree species influence on soils in the laboratory.
For additional information about this research study see
the 2005 CFER
Annual Report. (2.2 MB)
All objectives for this study have been met. A Master's thesis (Cross 2006) was defended July 27, 2006. The final thesis will be available
soon from the CFER program office.
