| Profiling Diseases
Using Landscape Metrics to Measure Suitability of a Forested
Watershed for Different Objectives
Forest managers traditionally treat a forest as a collection of
stands, where each stand is inventoried and managed for specific
objectives. Several contiguous stands make up a watershed. The easily
identified boundaries of a watershed have resulted in this geographic
boundary becoming an important landscape for management. Characterizing
the complexity of a landscape within the planning process has been
a challenge. Finer scaled techniques are not always appropriate
for large spatial scales, such as a watershed. Rocky Mountain Research
Station scientists worked with National Forest planners to demonstrate
the utility of profiling as a tool for forest planning, and the
utility of comparing several metrics for spatial heterogeneity based
on distribution of stands with suitable characteristics under actual
and optimal conditions on a watershed. Optimal conditions are defined
by expert opinions. The actual condition over the watershed, as
determined from existing stand inventory data, is then compared
with target conditions using an analysis method called profiling,
which develops profiles using a multidimensional scaling (MDS) procedure.
Profiles for various target landscapes are plotted in MDS. The distance
from the center of the target space to the plotted position of the
actual stand is a measure of dissimilarity. By comparing the condition
of the actual watershed with what the experts envisioned would be
optimal, suitability of the watershed for the given use can be quantified.
Planners will then have an idea of whether the watershed can be
managed to reach the desired objective, and managers will have a
tool to monitor changes over time for evaluating progress toward
meeting forest plans.
Citation: Lundquist, J.E., L.R. Lindner, and J. Popp. 2001. Using
landscape metrics to measure suitability of a forested landscape:
a case study for old growth. Canadian Journal of Forestry Research.
31:1786-1792.
Integrating concepts of landscape ecology with the molecular
biology of forest pathogens
Rocky Mountain Research Station scientists John Lundquist and Ned
Klopfenstein argue that, rather than focusing research on characterizing
diversity within forest pathogens using molecular markers, we need
to also broaden our scope to characterize the features of the landscape
that help create or maintain this microbial diversity. Forest diseases
commonly occur in a patchwork across natural landscapes, with resultant
diversity in genetic composition of fragmented populations. Genetic
diversity is a result of local adaptation caused by evolutionary
forces that can act rapidly in tiny microbes. The challenge is to
determine what genetic level is meaningful at the landscape (metapopulation)
scale. Understanding the dynamics of disease in complex ecosystems
has always been a major issue in forestry: big, slow-acting forests
trying to fight off small, fast microbes. Now, geographic information
systems (GIS), spatial analysis and modeling, and remote sensing
give us the tools to detect and interpret genetic differences across
broad disease populations. Integrating molecular biology with landscape
ecology will help land managers better understand, and deal with,
forest disease patterns and the processes that produce them.
Citation: Lundquist, JE, Klopfenstein, NB. 2001. Integrating concepts
of landscape ecology with the molecular biology of forest pathogens.
Forest Ecology and Management 150: 213-222.
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