Minireviews: Neighborhood Effects, Disturbance Severity, and Community Stability in Forests |
| |
Authors: | Lee E Frelich Peter B Reich |
| |
Institution: | (1) Department of Forest Resources, University of Minnesota, 1530 North Cleveland Avenue, St. Paul, Minnesota 55108, USA , US |
| |
Abstract: | A theoretical framework and conceptual model for temporal stability of forest tree-species composition was developed based
on a synthesis of existing studies. The model pertains primarily to time periods of several tree lifetimes (several hundred
to a few thousand years) at the neighborhood and stand spatial scales (0.01–10 ha), although a few extensions to the landscape
scale are also made. The cusp catastrophe was chosen to illustrate compositional dynamics at the stand level for jack pine,
northern hardwood, and white pine forests in the Great Lakes Region of the United States and for tropical rainforests in the
northern Amazon basin. The models feature a response surface (degree of dominance by late-successional species) that depends
on two variables: type of neighborhood effects of the dominant tree species and severity of disturbances. Neighborhood effects
are processes that affect the chance of a species replacing itself at the time of disturbance (they can be positive, neutral,
or negative) and are of two types: overstory–undestory effects, such as the presence of advanced reproduction; and disturbance-activated
effects, such as serotinous seed rain. Disturbance severity is the proportion of trees killed during a disturbance. Interactions
between neighborhood effects and disturbance severity can lead to either punctuated stability (dramatic but infrequent change
in composition, in those forests dominated by species with positive neighborhood effects) or succession (continuous change,
in those forests dominated by species with neutral-negative neighborhood effects). We propose that neighborhood effects are
a major organizing factor in forest dynamics that provide a link across spatial scales between individual trees and disturbance/patch
dynamics at the stand and landscape scales.
Received 23 June 1998; accepted 16 December 1998. |
| |
Keywords: | : community stability disturbance severity neighborhood effects punctuated stability succession |
本文献已被 SpringerLink 等数据库收录! |
|