A PROPOSED DESIGN
FOR MONITORING CHANGES
IN VEGETATION HEALTH AND VIGOR
IN ALASKA
Vernon J. LaBau
Project Leader
Anchorage Forestry Sciences Laboratory
201 East 9th Avenue, Suite 303
Anchorage, Alaska 99501
ABSTRACT
There is evidence that much of the Alaska flora are sensitive to the impact of global climate change.
This paper proposes a methodology for monitoring the health and vigor of Alaska vegetation to seek
evidence of global climate changes. The monitoring concept, based, in part, on a system developed for
assessing vegetation biomass and plant composition, would be applied in the boreal and temperate forests
of interior and coastal Alaska. To capture vegetation change in these sensitive forests, it is
important that a monitoring system be established in Alaska soon.
BACKGROUND
During the past decade, the scientific, social
and political arenas have become increasingly
concerned about the worldwide health of forests.
But only recently have acid rain, stratospheric
ozone depletion and atmospheric carbon loading
become targets of significant public attention
and scientific study (Office of the President,
1989). As concern grew, more scientists began
examining reductions in forest area and changes
in forest health for evidence of global climate
change.
The scientific community is particularly
interested in establishing programs for
monitoring the health and vigor of vegetation.
Generally these programs are envisioned as
observation and measurement of vegetation changes
in systematically located sites. The sites would
be visited initially to determine the current
health and vigor of the vegetation. Then,
periodic visits would be made to determine any
changes in health and vigor.
The studies would be designed to establish a
significant relationship between observed changes
and whatever was causing the changes. If the
changes are related to climatic shifts or some
form of atmospheric change, then, hopefully,
statistical analysis will correlate plant changes
to global climate shifts. For example, it is
hoped that statistical relationships may be shown
through evaluation of chemical analyses of
vegetation and soils and climatic or atmospheric
changes.
Arctic vegetation is expected to react early to
global climate change because harsh growing
condition cause many "indicator plants" to exist
in a naturally stressed condition. If stress is
reduced, for example, by climate warming, the
plants should show increased growth. If some
other condition becomes a factor, such as acid
rain, those stressed indicator plants may
disappear from the ecosystem. For this reason,
it's important that a monitoring program be
established soon in Alaska.
However, global climate change may not be the
only factor affecting vegetation change.
Therefore, studies must be designed to capture
other possible relationships as effectively as
possible, given limitations of money, personnel
and time.
Our monitoring design interfaces with the Global
Change Research Program (GCRP) of the Pacific
Northwest and the Pacific Southwest Forest and
Range Experiment Stations (USDA, 1990). The GCRP
emphasizes better understanding and management of
interactions between climate change, air
chemistry and ecosystems processes and
productivity in four ecosystems chosen for study.
GCRP integrates process and small-scale response
research with watershed- and landscape- level
studies.
Our monitoring design also is directly connected
with work being done by the Atmospheric
Deposition/Vegetation Survey Research Development
and Application Program of the US Forest Service
in Triangle Park, NC (Barnard, 1990).
A sound time-series plant monitoring program must
begin with baseline information on health and
vigor. Forest Inventory and Analysis (FIA)
Research Work Units of the US Forest Service have
a nationwide set of baseline data and information
on forest and rangelands that appears to apply to
such a study.
Since enactment of the McSweeney-McNary Act of
1928, Forest research (formerly called Forest
Survey) teams in the United States have
characterized forest vegetation at sample plot
locations and extrapolated this information to
the larger population. Initially, this was done
primarily for the purpose of estimating timber
areas, volume, growth and mortality.
Passage of the Resources Planning Act (RPA) in
1974 by the US Congress empowered Forest
Inventory and Analysis (FIA) research units to
evaluate all vegetation on forest and rangelands.
Since then, many FIA units have developed
methodologies for evaluating all vegetation
within sample areas.