INVESTIGADORES
MARCO Diana Elizabeth
artículos
Título:
Invasion of Gleditsia triacanthos in Lithraea ternifolia montane forests of central Argentina
Autor/es:
DIANA MARCO; SERGIO PAEZ
Revista:
Environmental Management
Referencias:
Año: 2000 vol. 26 p. 409 - 419
Resumen:
ABSTRACT / The aim of this work is to study the invasion
system constituted by the alien species Gleditsia triacanthos
and the native dominant Lithraea ternifolia in montane forests
of central Argentina, considering life history and demographic
traits of both the alien and the native species and
different site conditions for population growth (good and bad
sites). Matrix models are applied to project the consequences
of differences in vital rates for population growth.
Analyzing these models helps identify which life cycle transitions
contributed most to population growth. Obtained population
growth rates are considered to assess predicted rates
of spread using the reaction-diffusion (R-D) model.
G. triacanthos presents many of the life history traits that
confer plants high potential for invasiveness: fast growth,
clonal and sexual reproduction, short juvenile period, high
seed production, and high seed germinability. These traits
would ensure G. triacanthos invasive success and the displacement
of the slow-growing, relatively less fecund native
L. ternifolia. However, since disturbance and environmental
heterogeneity complicate the invasibility pattern of G. triacanthos
in these montane forests, the outcome of the invasion
process is not straightforward as could be if only life
history traits were considered.
Great variation in demographic parameters was observed
between populations of each species at good and bad sites.
Though both good and bad sites signified increasing or at
least stable populations for G. triacanthos, for L. ternifolia
bad sites represented local extinction. Analyzing the results
of matrices models helps design the optimal management
for the conservation of L. ternifolia populations while preventing
the invasion by G. triacanthos. The predicted asymptotic
rate of spread for G. triacanthos at the good site was fourfold
greater than the predicted one for L. ternifolia, although the
difference was much smaller considering the bad site. The
usefulness of the R-D model to study this invasion system is
discussed.
seed production, and high seed germinability. These traits
would ensure G. triacanthos invasive success and the displacement
of the slow-growing, relatively less fecund native
L. ternifolia. However, since disturbance and environmental
heterogeneity complicate the invasibility pattern of G. triacanthos
in these montane forests, the outcome of the invasion
process is not straightforward as could be if only life
history traits were considered.
Great variation in demographic parameters was observed
between populations of each species at good and bad sites.
Though both good and bad sites signified increasing or at
least stable populations for G. triacanthos, for L. ternifolia
bad sites represented local extinction. Analyzing the results
of matrices models helps design the optimal management
for the conservation of L. ternifolia populations while preventing
the invasion by G. triacanthos. The predicted asymptotic
rate of spread for G. triacanthos at the good site was fourfold
greater than the predicted one for L. ternifolia, although the
difference was much smaller considering the bad site. The
usefulness of the R-D model to study this invasion system is
discussed.
G. triacanthos presents many of the life history traits that
confer plants high potential for invasiveness: fast growth,
clonal and sexual reproduction, short juvenile period, high
seed production, and high seed germinability. These traits
would ensure G. triacanthos invasive success and the displacement
of the slow-growing, relatively less fecund native
L. ternifolia. However, since disturbance and environmental
heterogeneity complicate the invasibility pattern of G. triacanthos
in these montane forests, the outcome of the invasion
process is not straightforward as could be if only life
history traits were considered.
Great variation in demographic parameters was observed
between populations of each species at good and bad sites.
Though both good and bad sites signified increasing or at
least stable populations for G. triacanthos, for L. ternifolia
bad sites represented local extinction. Analyzing the results
of matrices models helps design the optimal management
for the conservation of L. ternifolia populations while preventing
the invasion by G. triacanthos. The predicted asymptotic
rate of spread for G. triacanthos at the good site was fourfold
greater than the predicted one for L. ternifolia, although the
difference was much smaller considering the bad site. The
usefulness of the R-D model to study this invasion system is
discussed.
seed production, and high seed germinability. These traits
would ensure G. triacanthos invasive success and the displacement
of the slow-growing, relatively less fecund native
L. ternifolia. However, since disturbance and environmental
heterogeneity complicate the invasibility pattern of G. triacanthos
in these montane forests, the outcome of the invasion
process is not straightforward as could be if only life
history traits were considered.
Great variation in demographic parameters was observed
between populations of each species at good and bad sites.
Though both good and bad sites signified increasing or at
least stable populations for G. triacanthos, for L. ternifolia
bad sites represented local extinction. Analyzing the results
of matrices models helps design the optimal management
for the conservation of L. ternifolia populations while preventing
the invasion by G. triacanthos. The predicted asymptotic
rate of spread for G. triacanthos at the good site was fourfold
greater than the predicted one for L. ternifolia, although the
difference was much smaller considering the bad site. The
usefulness of the R-D model to study this invasion system is
discussed.