379of spatially explicit modeling, a compelling question or objective justifying the
need to do spatially explicit modeling should be a prerequisite to developing a spa-
tial STSM. That said, good cases for spatially explicit STSMs can usually be made
for wildlife management, nonnative plant species control and monitoring (Frid and
Wilmshurst 2009 ; Frid et al. 2013a, b), and wildland fire (Miller 2007 ). In these
cases, the position and size of natural and managed transitions can critically affect
project-specific metrics that track the condition of ecological systems studied.
Extreme weather events and climate projection do vary across the landscape. Thus,
studies looking to consider these issues ought to include a spatial component. There
are a number of nonspatial (Evers et al. 2011 , 2013 ; Provencher et al. 2013 ; Low
et al. 2010 ; Forbis et al. 2006 ; Creutzburg et al. 2012 ) and spatially explicit
(Provencher et al. 2007 ) STSM applications with a Bromus component.
13.2.6 Uses and Benefits of State-and-Transition
Simulation Modeling
While conceptual STMs are useful tools for describing vegetation dynamics and
identifying possible management prescriptions at the site-specific scale, they can fall
short of providing prognostic information for landscape scale vegetation manage-
ment efforts. Land managers are frequently faced with limited resources and compet-
ing objectives and an interest in knowing how their actions will play out on the
landscape. For example, should restoration resources be applied toward areas affected
by woody species encroachment or toward areas affected by annual species inva-
sions? In addition to competing objectives such as these, land managers are often
faced with uncertainties and incomplete information of the vegetation dynamics for
the landscape of concern. Despite these challenges, land managers must frequently
make decisions about the allocation of limited vegetation management resources. At
landscape scales, STSMs are valuable tools for identifying robust management strat-
egies, important trade-offs, and critical uncertainties for decision making.
STMs are popular among range and forest managers because they are easy to
communicate and typically require less data to parameterize than more complex
process-based models under different applications. However, STSMs can include
information from process-based models and analysis (Halofsky et al. 2013 ). These
models are management oriented and simulations can be useful to solve complex
management questions. STSMs have the major benefits of being flexible and foster-
ing stakeholder engagement and buy-in (Price et al. 2012 ; Nixon et al. 2014 ).
Simulations have the ability to predict changes in vegetation under different scenar-
ios considering alternative management actions and hypotheses about the response
of natural systems to them. The variety of scenarios that can be explored—from cli-
mate change to single management actions (e.g., prescribed burning)—is very large
and feasible. The social benefit of model building is that it allows land managers and
scientists to explicitly document their understanding and assumptions about ecologi-
cal processes, management actions, and the interactions between the two. Such a
13 State-and-Transition Models: Conceptual Versus Simulation Perspectives...