Jerry Franklin - Early seral forest: a diminishing resource?

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Jerry Franklin - Early seral forest: a diminishing resource?

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Jerry Franklin - Early seral forest: a diminishing resource?

  1. 1. What is a “good” forest opening? <ul><li>Is the future a concern? </li></ul>
  2. 2. Early Successional Communities <ul><li>What is high quality early seral forest habitat? </li></ul><ul><li>How has it been created in the past? </li></ul><ul><li>Where will it be provided in the future? </li></ul><ul><li>What silvicultural tools can provide for this habitat? </li></ul>
  3. 5. Well, let’s take a look at nature’s varieties of early successional communities on forested sites * Most notably, they are not dominated by trees!
  4. 6. Attributes of Early Successional Communities on Forest Sites Jerry F. Franklin and Mark Swanson University of Washington (jff@u.washington.edu)
  5. 7. Definition: <ul><li>Early successional communities are the communities that occupy potentially forested sites between the time of a stand-replacement disturbance and re-establishment of a closed forest canopy </li></ul>
  6. 11. Early Successional Communities <ul><li>Altered (non-forest-dominated) microclimate </li></ul><ul><li>Structurally rich (with most natural disturbances) </li></ul><ul><li>Biodiversity rich </li></ul><ul><li>Process rich (alterations in ecosystem functions) </li></ul>
  7. 12. Altered microclimate: <ul><li>Not dominated by trees! </li></ul><ul><li>Sunny, greater microclimate extremes </li></ul><ul><li>Heterogeneity </li></ul><ul><li>Terrestrial (non-tree) and aquatic ecosystems “bloom” </li></ul>
  8. 15. Structurally rich: <ul><li>Wood legacies (snags & logs) </li></ul><ul><ul><li>Habitat </li></ul></ul><ul><ul><li>Long-term energy/nutrient source </li></ul></ul><ul><ul><li>Physical interactions </li></ul></ul><ul><ul><li>PERSISTS & ONLY SOURCE of CWD for MANY DECADES </li></ul></ul><ul><li>Diversity and balance (evenness) in plant life forms </li></ul>
  9. 25. Biologically rich: <ul><li>Most biodiverse of forest stages </li></ul><ul><li>Diversity composed of </li></ul><ul><ul><li>Legacy species </li></ul></ul><ul><ul><li>Opportunists (weeds?) </li></ul></ul><ul><ul><li>Habitat specialists </li></ul></ul><ul><ul><li>Predators (land & water) </li></ul></ul><ul><li>Adapted, native tree genotypes </li></ul>
  10. 29. Black-backed woodpecker. Photo: Dr. R. Hutto
  11. 30. Three-toed woodpecker. Photo: Dr. R. Hutto
  12. 31. Mountain Bluebird. Photo: Dr. R. Hutto
  13. 32. Olive-sided Flycatcher. Photo: Dr. R. Hutto
  14. 33. Western meadowlark. Photo: Dr. R. Hutto
  15. 34. White-crowned sparrow. Photo: Dr. R. Hutto
  16. 35. Garter Snake. Photo: Dr. C. Crisafulli.
  17. 36. Process Alterations (Terrestrial): <ul><li>Significant nitrogen fixation </li></ul><ul><li>Accelerated nutrient cycling </li></ul><ul><li>Diversity in primary productivity </li></ul><ul><ul><li>More complex food webs </li></ul></ul><ul><ul><li>Increased herbivory </li></ul></ul><ul><li>Effects on hydrologic cycle </li></ul><ul><ul><li>Often, increased flows </li></ul></ul>
  18. 39. Process Alterations (Aquatic): <ul><li>Significant primary productivity </li></ul><ul><li>More diverse allochthonous inputs </li></ul><ul><li>Richer food webs </li></ul><ul><li>Greater fish production </li></ul>
  19. 41. Other Attributes of ESFCs: <ul><li>Duration – highly variable depending upon disturbance size, type, and chance </li></ul><ul><ul><li>Example short: small windthrow </li></ul></ul><ul><ul><li>Example long: large or repeated wildfire or fire on severe site </li></ul></ul><ul><li>Heterogeneity – initial & developmental </li></ul>
  20. 44. Ecological Importance of ESFCs <ul><li>Opportunity for organisms and processes absent/poorly represented under closed forest </li></ul><ul><li>Opportunity for nutrient recharge </li></ul><ul><li>Regional and local hotspots of biological diversity (source areas) </li></ul>
  21. 49. So, what is high quality early successional habitat? <ul><li>Early successional communities with a large array of structural and organismal legacies and </li></ul><ul><li>Exhibiting heterogeneity in space and time and </li></ul><ul><li>Diverse in life forms, food webs, and ecosystem processes </li></ul>
  22. 50. Does the job! <ul><li>Provides for the richness of </li></ul><ul><li>Biodiversity </li></ul><ul><li>Functional diversity </li></ul><ul><li>That we want to sustain in our forest landscapes </li></ul>
  23. 53. How has it been created in the past?
  24. 57. How (where) will it be provided for in the future?
  25. 62. What management tools can provide for this habitat?
  26. 63. Best management tool for early successional habitat: CONSERVE IT WHEN AND WHERE NATURE CREATES IT
  27. 66. Naturally-regenerated ESFCs are likely to be more resilient under climate change due to - greater species diversity - tree genotypes selected by nature (i.e., environmental stresses)
  28. 74. Pacific Tree Frog. Photo: Dr. C. Crisafulli.
  29. 75. What is a “good” forest opening? <ul><li>Is the future a concern? </li></ul>
  30. 77. Where management goals are primarily oriented toward characteristic biodiversity and ecological processes,“hurrying” ecosystem development through the pre-canopy closure stage is not appropriate
  31. 78. Salvage: <ul><li>WILL eliminate key structural legacies </li></ul><ul><ul><li>Key habitat and substrate, so many secondary effects on biota </li></ul></ul><ul><ul><li>This is a LONG TERM impact, since no new CWD for many decades </li></ul></ul><ul><li>WILL destroy/damage recovering vegetation </li></ul><ul><li>MAY cause damage to aquatic ecosystems and and soils </li></ul>
  32. 79. Salvage logging never contributes directly to ecological recovery Salvage logging is always a tax on ecological recovery; the tax may be large or small
  33. 80. Reforestation will usually: <ul><li>Reduce the duration of ESFCs </li></ul><ul><li>Reduce heterogeneity of the process by which closed forest canopy is re-established </li></ul><ul><li>Alter genotype of planted species (less selection by environment) </li></ul><ul><li>Homogenize composition of forest </li></ul>
  34. 81. Potential negative management <ul><li>Early SFCs need full compliment of biological legacies to fully function </li></ul><ul><li>Salvage will reduce functionality </li></ul><ul><li>Reforestation will truncate & modify ESFCs </li></ul><ul><li>Naturally-regenerated ESFCs are more likely to be resilient to climate change (more diverse, good genotypes) </li></ul>
  35. 83. Blue Grouse. Photo: Dr. C. Crisafulli.
  36. 85. Principle 3: Conservation of biological legacies is critical for postfire reestablishment of characteristic levels of ecosystem processes & biodiversity
  37. 87. Principle 5: Whatever activities are undertaken – seek to avoid causing additional harm and to enhance natural recovery processes!
  38. 88. BIOLOGICAL LEGACIES <ul><li>Organisms and reproductive structures </li></ul><ul><li>Structures and organic matter </li></ul><ul><li>Organically-derived spatial patterns </li></ul>
  39. 90. Salvage of dead wood <ul><li>Done to capture socio-economic value </li></ul><ul><li>Has negative impacts on recovery </li></ul><ul><li>Removal of legacies is most profound long-term impact </li></ul>
  40. 92. Timber salvage rarely, if ever, contributes directly to ecological recovery, including native biodiversity
  41. 93. Salvage is always a tax on ecological recovery! The tax may be large or small depending upon the salvage operation.
  42. 94. Importance of Coarse Wood <ul><li>Habitat for species </li></ul><ul><li>Organic seedbeds (nurse logs) </li></ul><ul><li>Modification of microclimate </li></ul><ul><li>Protection of plants from ungulates </li></ul><ul><li>Sediment traps </li></ul><ul><li>Sources of energy & nutrients </li></ul><ul><li>Sites of N-fixation </li></ul><ul><li>Special source of soil organic matter </li></ul><ul><li>Structural elements of aquatic ecosystems </li></ul>
  43. 95. The early post-disturbance period of forest ecosystem development - pre-tree-canopy closure – is profoundly important!
  44. 96. Deer Mouse. Photo: Dr. C. Crisafulli.
  45. 97. Montane Shrew. Photo: Dr. C. Crisafulli.
  46. 98. Northern Pocket Gopher. Photo: Dr. C. Crisafulli.
  47. 100. Where management goals are directed to sustaining ecosystem services and biodiversity, most postdisturbance “restoration” activities are inappropriate
  48. 101. MAJOR EXCEPTION: Human intercession may contribute ecologically where the disturbances are unique (uncharacteristic) in either intensity or frequency or invasive species are involved

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