Landscapes Forest and Global Change - ESA - Escola Superior ...

J. Russell et al. 2010. Developing models and processes to aid decision support for integrated land management
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Habitat supply models were developed for each of 17 species selected to evaluate the potential
of the FM area to provide suitable habitat (Van Damme et al. 2003). The models define habitat
suitability based on the provision of habitat elements required for survival and reproduction.
Within the models, special habitat element models were developed to characterize changes in
condition (i.e. abundance, density) of habitat elements through forest succession and disturbance.
Specific (i.e. canopy closure, tree height), general (i.e. perches, hiding cover) and habitat uses
(i.e. food) were included in the analysis. Habitat supply models projected suitability based on
home range size for each species and were used to assess each forest harvest scenario at 5-year
time steps. Additionally, the special habitat elements were analyzed within the habitat supply
model to determine a subset of elements that were most critical for the 17 species. These were
then associated with silvicultural practices, seral stages and dominant species groups and
embedded within the timber supply model as constraints.
2.3 Water
The Forest Watershed and Riparian Disturbance (FORWARD) project developed hydrologic
models at two spatial scales (first- and third-order watershed) to predict how forest harvesting
would change precipitation-normalized stream runoff at the watershed outlet (i.e. corrected for
both watershed area and precipitation inputs). This variable, termed a runoff coefficient, was
predicted for a given set of watershed attributes under forested conditions using a variant of the
Soil and Water Assessment Tool (SWAT) (Arnold et al. 1998). The data to populate these
runoff coefficient models were collected before and after experimental harvest from treatment
and reference watersheds. Data included streamflow at a high temporal resolution, as well as
improved digital elevation model, slope, soil and wetland coverage, and watershed boundaries.
SWAT simulations are still underway to compare measured to predicted runoff coefficients with
time after harvest and to calibrate the model for future FM planning cycles (Watson et al. 2008).
Water quality is being incorporated into SWAT modelling, as well as artificial neural network
modelling (Nour et al. 2006). The FORWARD project established indicators and ranges of
acceptability in changes in streamflow based upon changes in runoff coefficients (Prepas et al.
2008). Thus, potential changes to streamflow could be given equal or varying weight as
compared to other forest values during the development of a FM plan.
3. Results and Discussion
The structure of the FM planning analysis is hierarchical. The first task was to set the future
landbase condition that included climate and vegetation change, human population change,
wildfire response to these two conditions and oil and gas activities (Fig. 2). This produced a
landscape change outside the normal projection (i.e. these issues are not included in a standard
timber supply model). These conditions act as forest landbase constraints: over the standard
planning period of approximately 200 years these conditions enact significant changes in the
forest land base and forest growth patterns. This then produced future land base series on which
we could overlay a timber supply analysis. This analysis includes the constraints of biodiversity
(BAP) and water (FORWARD) (Fig 2). This was conducted for multiple future scenarios at two
basic levels of projection: multiple scenarios of each component part (e.g., different oil and gas
scenarios could be incorporated into the model leaving all other components static) and
projections with various elements turned on or off, dependent upon what multiple effects needed
to be focused upon for analysis. In this manner any number of iterations could be undertaken to
arrive at an understanding of how each element affects the system at certain levels or how
various combinations of elements can affect the system based on projected future scenarios.
The system described above is a logical evolution from the standard timber supply analysis
employed in much of Canada to a more holistic model concept that looks at all issues facing a
forest state. It is critical to model elements of varying forest values outside of traditional
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.