Structure, diversity, and biophysical properties of old-growth forestsin the Klamath region, USA

Northwest Science
By:  and 



The diverse old-growth forests in Klamath region of northern California and southern Oregon provide valuable ecosystem services (e.g., maintaining watersheds, wildlife habitat, recreation), but may be vulnerable to a wide range of stressors, including invasive species, disrupted disturbance regimes, and climatic change. Yet our understanding of how forest structure in the Klamath region relates to the current physical environment is limited. Here we provide present-day benchmarks for old-growth forest structure across a climatic gradient ranging from coastal to dry interior sites. We established 16 large (1 ha) forest plots where all stems > 5 cm in diameter were identified to species and mapped. Climate across these sites was highly variable, with estimated actual evapotranspiration correlated to several basic measures of forest structure, including plot basal area, stem size-class inequality, tree species diversity and, to a lesser extent, tree species richness. Analyses of the spatial arrangement of stems indicated a high degree of non-uniformity, with 75% of plots showing significant stem clumping at small spatial scales (0 to 10 m). Downscaled predictions of future site water balance suggest changes will be dominated by rapidly increasing climatic water deficit (D, a biologically meaningful index of drought). While these plots give a picture of current conditions, continued monitoring of these stands is needed to describe forest dynamics and to detect forest responses to ongoing and future stressors.

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Publication type Article
Publication Subtype Journal Article
Title Structure, diversity, and biophysical properties of old-growth forestsin the Klamath region, USA
Series title Northwest Science
DOI 10.3955/046.089.0208
Volume 89
Issue 2
Year Published 2015
Language English
Publisher BioOne
Contributing office(s) Western Ecological Research Center
Description 12 p.
First page 170
Last page 181
Country United States
Other Geospatial Klamath region
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
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