Classification and dynamics of developmental stages in late-successional temperate forests

摘要: Late-successional forests often have complex disturbance histories that can result in stands with widely varying structure, ranging from young pole to uneven-aged old growth. Arranging chronosequences, however, is problematic because ‘stand age’ not a meaningful concept for multi-aged and ‘time since last stand-replacing disturbance’ cannot be determined tree-ring evidence. In this paper, we describe systematic approach classifying developmental stages late-successional using structural metrics known correlated key ecological properties such as total biomass, carbon storage, stand production rates, wildlife habitat. While conceptually based on the amount of aggregate crown area occupied by different size classes trees, computations study, ease use, are entirely absolute relative basal four (saplings, poles, mature, large trees). Eight forest recognized, including growth (early-, mid-, late-transition, steady state). The method was used classify 70 primary northern hardwood (Acer–Betula–Tsuga) landscape reserves upper Michigan, USA. degree which mimic underlying temporal trends dynamics investigated aid 30-year permanent plot records multi-century simulations CANOPY model. Results indicated good correspondence between postulated sequence field compared changes over time observed plots. support Bormann–Likens hypothesis number trees reaches maximum toward end lifespan an even-aged cohort subsequently declines state. most plots were uneven-aged, both data suggest pathways after very similar difficult distinguish form distributions. study landscapes, 78% classified growth, 39% early or mid-transition late transition should useful, appropriate site-specific modifications, evaluating meet goals under forestry methods, monitoring responses environmental change, examining biotic along gradient development following disturbance.