http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
formalism for characterizing vegetation responses using classification trees and Dempster-Shafer theory of evidence
xiv, 151 leaves : illustrations ; 28 cm.
Predictive models of vegetation change are urgently needed
for range management and conservation purposes. Traditional
approaches based on climax equilibrium theory do not fit
observed dynamics of important types of grasslands and
shrublands. Most alternative communityand species-based
models require sophisticated information, are only locally
applicable or produce predictions that are not directly
interpretable for management decisions. Infon-nation
currently gathered in management settings is mostly ignored
despite its potential utility for predicting species
responses to disturbance regimes/events and management
practices. This study merges elements of comparative and
functional ecology in a conceptual approach to employ
managementlevel knowledge and autecological information 'in
the characterization of vegetation responses. A formalism is
proposed for practical applications that includes specific
methods for identifying response groups of species and
criteria for establishing agreement among expert sources.
Classification trees are used for arranging individual
species 'into response groups according to autecological
similarities for a set of adaptive attributes and specific
responses obtained from expert sources. Profiles of
attributes associated with responses to individual
disturbance factors are then combined and most probable
trends for response groups are generated using DempsterShafer
mathematical theory of evidence. Predictive rules and
attached belief intervals can be produced for every non-empty
combination of autecological profiles previously detemiined
for individual disturbance factors. TMs provides generality
and portability across physiognomically similar vegetation
types. The species profile approach also has important
implications for the conservation of functional diversity and
risk evaluation of invasion potential by non-native species.
A general application of the formalism to the vegetation of
the Edwards Plateau (Texas, USA), involving predictions for
the effects of grazing and fire, is implemented and
limitations and future developments required are discussed.
"Major Subject: Rangeland Ecology and Management".
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