Historical Creation of Early Seral Habitat: Fire, Wind, Bugs
1. Historical Creation of Early Seral Habitat: Fire, Wind, Bugs … Fred Swanson USDA Forest Service Pacific Northwest Research Station
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6. Non-forest openings Patch size Persistence of early seral (yrs) 0 50 100 small large Mount St. Helens Blast zone – planted Canopy gap Mount St. Helens Blast zone - unplanted Mesic meadows Xeric meadows Lava flows Mount St. Helens Primary succ. zone Clearcuts fast (Yang et al) slow Wildfire tropics
13. Stand-Replacing Disturbance in Western Washington, 1972-2004 Fires Harvests 1972-1977 1977-1984 1984-1988 1988-1992 1992-1996 1996-2000 2000-2002 2002-2004 Volcanic eruption
14. Age Class Distributions in Coastal Oregon Source: various CLAMS analyses (Spies et al. 2007) Early seral
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Hinweis der Redaktion
Relative to HRV in the coast range, we have no shortage of early-seral forest in current landscape. Slide compares age-class distributions in current landscape (‘initial’, 1996) with HRV (300 years pre-Euro-settlement) and 100 years from now (CLAMS simulation – ignore for now). ~30% of current forest is early seral, vs. 3-12% historically.