Down wood and biodiversity — implications to forest practices

摘要: Many species require or use down wood (fine and coarse woody debris) as habitat. Where forestry has been practiced for several rotations large proportions of these are considered threatened. Key attributes determining the suitability habitat decay stage, tree species, size, specifically diameter. Both quantity distri- bution suitable influence species' presence abundance. We present a simple framework describing based on broad natural history features, derive predictions from framework, then test by review summary literature. Our focus is terrestrial vertebrates, particularly in Pacific Northwest. Species other than ver- tebrates addressed to ensure that metrics derived vertebrates also appropriate organisms. Basic same, but values span larger range among nonvertebrates. Current evidence suggests ''ex- tinction debt'' apparent nonvertebrates approaching vertebrates. Predictions underlying his- tory hold when tested. From basis we guidelines forest planning practice, suggest how regional target can be derived. Resume´ : Plusieurs especes necessitent ou utilisent le bois mort (debris ligneux fins grossiers) comme Laou ` l'on pratiquela foresterie au cours de plusieurs rotations, considere qu'une proportion ces deviennent menacees. Les caracteristiques determinant l'utilitedu regroupent l'etat decomposition, les es- peces d'arbres et leurs dimensions, surtout diametre. quantites ainsi que la distribution adequat influen- cent des leur abondance. auteurs presentent un cadre travail decrivant l'utilisation du mort, basesur elargies d'histoire naturelle, deduisent apartir d'un tel cadre, verifient finalement par une revue resumede litterature. On met l'accent sur vertebres terrestres, particuliere- ment region Pacifique nord-ouest. egalement d'autres vertebres, afin s'assurer chiffres inferes pour sont appropries organismes. mesures base restent memes, mais valeurs pertinentes couvrent plus spectre parmi non-vertebres. La preuve actuelle suggere « dette d'extinction » apparente non-vertebres approche celle vertebres. derivees l'histoire naturelle sous-jacente supportent mise al'epreuve. Sur cette base, directives larges planification pratique forestiere suggerent comment peut en deduire cible al'echelle regio- nale. Mots-cles: biodiversite ´ ,d ebris grossiers, d'extinction, pratiques forestieres, orga- nismes saproxyliques. (Traduit Redaction)