Sustainable management, earthquake disturbances, and transient dynamics: modelling timber harvesting impacts in mixed-species forests
Authored by Georges Kunstler, Robert B Allen, David A Coomes, Charles D Canham, Elaine F Wright
Date Published: 2013
DOI: 10.1007/s13595-012-0256-6
Sponsors:
New Zealand Foundation for Research Science and Technology
United Kingdom Natural Environment Research Council (NERC)
Platforms:
SORTIE
Model Documentation:
Other Narrative
Flow charts
Mathematical description
Model Code URLs:
Model code not found
Abstract
There is strong interest in sustainable forest management systems that
preserve characteristics of forests close to naturalness. Assessing the
effectiveness of these systems is difficult because defining
``natural{''} baselines from which impacts are estimated is challenging
and because the influence of harvesting can have complex interactions
with major natural disturbances.
We used SORTIE/NZ, an individual tree-based forest dynamics model, to
understand how harvesting and earthquake disturbance affect the dynamics
of a New Zealand podocarp-angiosperm forest.
Having parameterized SORTIE/NZ with extensive field data, we ran
simulations for three natural dynamics scenarios (no disturbance and two
earthquake scenarios) and then added podocarp harvesting scenario to
each of these.
Simulations suggest that this forest is experiencing transient dynamics, with a natural rise in the dominance of one species of slow-growing
podocarp with and without earthquake. Harvesting podocarps strongly
affected its increase in basal area.
Our results indicate that transient dynamics may occur in mixed podocarp
forests and major disturbances may have complex interactions with
management. Evaluating management impacts without accounting for these
complex dynamics may be misleading. Models make predictions about
transient trajectories that may help to evaluate these impacts.
Tags
Climate
Land-use
Variability
Rain-forest
Vegetation
New-zealand
Temperate
Growth nothofagus forests
Shade-tolerance
South-island