Disturbance, succession, and maintenance of species diversity in an East Texas forest.

摘要: Vegetation change following selective logging and major natural disturbance was in- vestigated through the use of stand history reconstruction population monitoring in an east Texas pine-hardwood forest. High frequencies release beech (Fagus grandifolia) white oak (Quercus alba) occurred after apparently disturbances 1800-1810, 1860-1870, 1960-1970, beginning 1910. Pulses recruitment all except most recent one. Age data suggest that 1910 asynchronous among species, with loblolly pine (Pinus taeda) regenerating first, followed sequentially by oak, red maple (Acer rubrum), beech. At present, only magnolia (Magnolia grandiflora) is showing significant new recruitment. After disturbance, pines grew rapidly became dominant re-forming overstory. Most hardwoods originating 19 10 did not reach White initially outgrew presently larger. Over last 20 yr growth has been greater than growth, resulting a decline average size difference between individuals these species. Presently, mortality rates understory populations are high for sweetgum, blackgum, oaks, low magnolia. These latter two species also faster growing. Ifthese trends continue, will become increasingly predominant forest eventually overstory as well. Map show saplings small trees abundant under but Future therefore likely to accelerate succession more shade-tolerant parts now dominated re-initiate regeneration, including areas results pattern cyclical replacement driven which may help preserve diversity southern mesic forests.