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Fire effects on the vital rates and stochastic population growth rate of the rare shrub Lindera subcoriacea Wofford

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  • Department of Army, Fort Bragg and Camp Mackall Military Installations
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Understanding demographic vital rates and the factors that affect those rates are key components of successful conservation strategies for many threatened and endangered rare plant species. Lindera subcoriacea is a rare dioecious shrub that occupies isolated wetland habitats in a small number of locations in the southeastern United States. The species faces a number of threats to its continued persistence, including habitat destruction, invasive species, and population isolation. From 2011 to 2019, we collected demographic information from 290 L. subcoriacea individuals within 28 populations on Fort Bragg, North Carolina and used the data to estimate demographic vital rates in unburned populations and after being exposed to prescribed fire. We then constructed population matrices and estimated population growth rates under a 3-, 5-, and 10-year return interval. Results indicated that L. subcoriacea individuals have high survivorship in both burned and unburned populations, seed production was reduced 1- and 2-year post-fire, seed production was highly uneven across individuals, seedling recruitment was extremely low, and simulated population growth rates were only above 1.0 under the 10-year fire return interval. Taken together, these results indicate that (1) L. subcoriacea populations are persisting with population growth rates close to one, (2) the short-term impacts of fire on the overall population growth rate of L. subcoriacea, while only 2–3% may determine long-term population viability, and (3) extremely uneven seed production and limited recruitment of seedlings into larger size classes make L. subcoriacea populations vulnerable to stochastic demographic processes.
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Fire effects on the vital rates and stochastic population
growth rate of the rare shrub Lindera subcoriacea Wofford
Wade A. Wall .Andrew S. Walker .Janet B. Gray .Matthew G. Hohmann
Received: 7 July 2020 / Accepted: 19 October 2020 / Published online: 16 November 2020
ÓThis is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2020
Abstract Understanding demographic vital rates
and the factors that affect those rates are key
components of successful conservation strategies for
many threatened and endangered rare plant species.
Lindera subcoriacea is a rare dioecious shrub that
occupies isolated wetland habitats in a small number
of locations in the southeastern United States. The
species faces a number of threats to its continued
persistence, including habitat destruction, invasive
species, and population isolation. From 2011 to 2019,
we collected demographic information from 290 L.
subcoriacea individuals within 28 populations on Fort
Bragg, North Carolina and used the data to estimate
demographic vital rates in unburned populations and
after being exposed to prescribed fire. We then
constructed population matrices and estimated popu-
lation growth rates under a 3-, 5-, and 10-year return
interval. Results indicated that L. subcoriacea indi-
viduals have high survivorship in both burned and
unburned populations, seed production was reduced 1-
and 2-year post-fire, seed production was highly
uneven across individuals, seedling recruitment was
extremely low, and simulated population growth rates
were only above 1.0 under the 10-year fire return
interval. Taken together, these results indicate that (1)
L. subcoriacea populations are persisting with popu-
lation growth rates close to one, (2) the short-term
impacts of fire on the overall population growth rate of
L. subcoriacea, while only 2–3% may determine long-
term population viability, and (3) extremely uneven
seed production and limited recruitment of seedlings
into larger size classes make L. subcoriacea popula-
tions vulnerable to stochastic demographic processes.
Keywords Demography Fire trap Lauraceae
Lindera subcoriacea Longleaf pine Matrix models
Introduction
Anthropogenic factors are increasingly threatening the
persistence of plant species on a global scale (Giam
Communicated by Neal J. Enright.
W. A. Wall (&)M. G. Hohmann
US Army Corps of Engineers, Engineer Research and
Development Center, P. O. Box 9005, Champaign,
IL 61826, USA
e-mail: Wade.A.Wall@usace.army.mil
M. G. Hohmann
e-mail: Matthew.G.Hohmann@usace.army.mil
A. S. Walker
US Forest Service, 141 East Fisher Avenue, New Bern,
NC 28560, USA
e-mail: Andrew.Walker@usda.gov
J. B. Gray
Endangered Species Branch, Bldg 0-9125 McKellors
Road, Fort Bragg, NC 28310, USA
e-mail: jGrayjb74@gmail.com
123
Plant Ecol (2021) 222:119–131
https://doi.org/10.1007/s11258-020-01092-3(0123456789().,-volV)(0123456789().,-volV)
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