LABORATORY 9
Application of Geographic
Information Systems in Pest Management
March 20, 2007
Andy Roberts
Department of Entomology
- "Everything is related to everything else, but near
things are more related than distant things." ...... Waldo
Tobler's First Law of Geography.
Purpose:
- This laboratory session will present basic GIS concepts and applications
with emphasis on insect pest management in forest ecosystems.
Overview:
- The class will be divided into 8 groups of two students:
- 1) A hands-on discussion of maps and their characteristics to introduce
the concept of Geographic Information Systems (GIS). For a PDF version
of this lab lecture (click
here )
- 2) An introductory lecture/discussion period to examine GIS as a tool,
with emphasis on the Slow-the-Spread gypsy moth IPM Pilot Project
- 3) A simple exercise designed to give students experience with the methodology
for using GIS in problem-solving will be demonstrated.
Lab Problem:
For a PDF version of this problem: click here
- Montgomery County is suffering from high gypsy moth populations in specific
locations. Intervention with insecticides has been proposed as a method
to deal with this problem. You are a resource manager in the county and
have been given the task of delineating treatment areas based upon specific
characteristics. Your task is to determine the location, number, and size
of treatment blocks for several different treatment combinations based
on the criteria below:
- 1. Gypsy moths were monitored in Montgomery Co. with pheromone-baited
traps. While a trap catch of 1 is generally of little significance, for
this exercise we will assume it indicates potentially damaging populations.
Also, we will assume that there is no need to treat populations which
are not in decisuous forests, since gypsy moth primarily is a defoliator
of hardwoods. Thus, treatment will be applied only in areas where:
a) moth catch is 1 or greater and
b) land cover is deciduous forest.
- 2. Insecticides to be used are Dimilin (diflubenzuron) and Bacillus
thuringiensis.. Because of Dimilin's adverse effect on aquatic systems,
it cannot be used within 100 meters of streams and other water bodies.
Thus, the analysis must determine where Dimilin may be used and where
Bt must be used:
c) Bt must be used within 100 meters of streams.
d) Dimilin may be used in all other areas.
- 3. Treatments must be timed with larval development. Larvae develop
more slowly at lower temperatures, and there is a direct relationship
between temperature and elevation. Thus, larval development is slower
at high elevations, and treatments must be applied at different times
based on this factor:
e) treatments lower than 2500 feet will be applied first.
f) treatments at or above 2500 feet will be applied later.
Data layers:
You were provided figures of GIS data layers which might (or might not)
be useful in solving the problem. These will be discussed in class, but
it will be helpful to review these as they might provide insight into the
problem.
Using the information we discussed in class on the gypsy moth treatment
problem, create a table containing the area in acres and hectares for each
of the treatment combinations
1. Dimilin, early treatment
2. Dimilin, late treatment
3. Bt, early treatment
4. Bt. late treatment
Additional preparation and general electronic reference
materials available for your use:
- There are many WWW sites which pertain to GIS. These discuss GIS problems,
present new approaches and techiniques in GIS, describe GIS software,
serve as data repositories, or describe specific projects which use GIS.
Listed below are a few of the best or most significant (according to me)
sites which we encourage you to check out before class.
- The Gypsy Moth Slow-the-Spread
Web server (from VT Entomology). A good example of using GIS in large-scale
IPM programs.
- Many references and links
to GIS data and other info. A great place to start.
- USGS Home PageESRI
(ARC/INFO). Home of the most popular GIS software in the world.
