If forests are to be used in @entity515 mitigation projects, it is essential to understand and quantify the impacts of disturbance on net ecosystem productivity ( @entity2282 ; i.e., the change in ecosystem @entity505 (C) storage with time). We examined the influence of live tree and @entity400 ( @entity400 ) on @entity2282 during secondary succession based on data collected along a 500-year chronosequence on the Wind River Ranger District, Washington. We developed a simple statistical model of live and dead wood accumulation and decomposition to predict changes in the woody component of @entity2282 , which we call @entity2282 (w). The transition from negative to positive @entity2282 (w), for a series of scenarios in which none to all wood was left after disturbance, occurred between 0 and 57 years after disturbance. The timing of this transition decreased as live-tree growth rates increased, and increased as @entity400 left after disturbance increased. Maximum and minimum @entity2282 (w) for all scenarios were 3.9 and -14.1 Mg C ha-1 year-1, respectively. Maximum live and total wood C stores of 319 and 393 Mg C ha(-1), respectively, were reached approximately 200 years after disturbance. Decomposition rates (k) of @entity400 ranged between 0.013 and 0.043 year-1 for individual stands. Regenerating stands took 41 years to attain a mean live wood mass equivalent to the mean mass of @entity400 left behind after logging, 40 years to equal the mean @entity400 mass in 500-year-old forest, and more than 150 years to equal the mean total live and dead wood in an old-growth stand. At a rotation age of 80 years, regenerating stands stored approximately half the wood C of the remaining nearby old-growth forests (predominant age 500 years), indicating that conversion of old-growth forests to younger managed forests results in a significant net release of C to the atmosphere.

Successional changes in live and dead wood XXXX stores: implications for net ecosystem productivity.

@entity505 :: ('MESH:D002244', 'Chemical') :: ['carbon'] @entity400 :: ('MESH:D014202', 'Disease') :: ['CWD', 'coarse woody debris'] @entity2282 :: ('4311', 'Gene') :: ['NEP'] @entity515 :: ('CHEBI:29334', 'Chemical') :: ['CO2']
@entity505 :: (MESH:D002244,Chemical) :: ['carbon']
