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Ecotonal changes and altered tree spatial patterns in lower mixed-conifer forests, Grand Canyon National Park, Arizona, USA

J. N. Mast, J. J. Wolf


Summary - what did the authors do and why?

The authors looked at species specific patch development, establishment, and the effects of climate and/or disturbance regimes, including fire suppression, within ecotones of mixed-conifer and ponderosa pine ecosystems.

Publication findings:

The authors found that along the mixed-conifer/ponderosa pine ecotone there has been a shift toward increasing mixed-conifer forest, especially white fir and other shade-tolerant and fire-intolerant species in historical ponderosa pine stands due to fire suppression. Pole-sized white fir were clumped at all patch sizes due to a lack of thinning by fire. This has caused dense thickets of white fir that do not permit ponderosa pine seedlings from regenerating.

Fire and Ecosystem Effects Linkages

Due to fire suppression, pole-sized white fir were clumped at all patch sizes due to a lack of thinning by fire. This has caused dense thickets of white fir that do not permit ponderosa pine seedlings from regenerating.

The authors found that along the mixed-conifer/ponderosa pine ecotone there has been a shift toward increasing mixed-conifer forest, especially white fir and other shade-tolerant and fire-intolerant species in historical ponderosa pine stands due to fire suppression. Pole-sized white fir were clumped at all patch sizes due to a lack of thinning by fire. This has caused dense thickets of white fir that do not permit ponderosa pine seedlings from regenerating.