Transcript Starkey - York College of Pennsylvania

Geospatial Analysis of USDA/PDA Plum Pox Eradication Project Data
By Laura F. Starkey
Department of Biological Sciences, York College of Pennsylvania
Background on Plum Pox Virus
(PPV)
• PPV is a debilitating tree virus
• Infects stone (pitted) fruit trees such as; Peaches,
Plums, Almonds, Cherries, Apricots, etc. as well as
non-fruit bearing ornamental relatives
• Infected trees have reduced quality and quantity of
fruit production
• 4 strains located worldwide, USA only has PPV-D
located only in 4 counties in PA
• United States Dept. of Agriculture (USDA) and the
Pennsylvania Dept. of Agriculture (PDA) have
implemented The Plum Pox Eradication Project
USDA/PDA Survey Methods
Home Owner Survey
 100% of the host plants
are sampled
 Pre-2003 4 leaves were
collected from each host
plant, unless there was only
1 susceptible plant and then
8 leaves were taken
 Post-2003, 8 leaves are
collected from each host
plant.
Orchard Survey
 Pre-2003 orchards were
sampled using a random
zig-zag pattern for long
narrow blocks and a
crossing
pattern
for
relatively square blocks
 Post-2003, 100% of all
host trees were sampled
within 5 miles of a previous
positive site
Figure 1 – Land Use Map
This map displays the arrangement of Positive and
Susceptible locations as they occur over Land Use types
ArcGIS Methods
Results
 Obtain data (various sources; PASDA, USDA,
Chesapeake Bay project)
 Sort, organize, and group data into a Personal
Geodatabase (every data source has its own
projection and method of labeling)
 Create new attribute tables by extrapolating data
from multiple layers
 Create cost layer by overlapping two layers and
assigning color costs.
The Cost Map below indicates by color the most likely
areas where a positive plant may be found. The
USDA’s current homeowner survey method involves
surveying every susceptible tree on every property
located within the blue survey line (see below).
Figure 2 – Elevation Map
This map displays the arrangement of Positive and
Susceptible locations as they occur over Elevation
(meters above sea level)
With my results I suggest that properties be
prioritized based on my Cost Map. That way
every year when the survey ends, more
susceptible locations won’t be missed because
time was spent surveying the less susceptible
locations.
This Cost Map could be enhanced by including
another cost layer that would account for distance
from the nearest positive location.
Figure 5 - Cost Map
This map was created by giving each land use and
elevation feature a percentage of the color red based on
the number of positives found there, then overlaying the
maps
What is Geographic Information
Systems?
• Geographic Information Systems (GIS) contains 3
parts; the Geography (maps, GPS, etc), Information
(elevation, precipitation, land use, etc), and the
computer System (software and hardware) to combine
and make use of the previous 2 parts.
• GIS simply is applying location-dependent
information such as elevation to a map
• Allows for analysis of geographic-dependent data
Figure 3 – Land Use Histogram
Histogram of Positive and Susceptible location’s Land
Use types
Figure 4 – Elevation Histogram
Histogram of Positive and Susceptible location’s Elevation
My Project
• Make use of GIS in order to refine the
USDA and PDA’s eradication project
• Look at Land Usage and Elevation of
positive and susceptible locations in order to
create a Cost map of most susceptible
locations
Acknowledgements
• Dr. Bruce Smith, Mentor
• Donald Albright, Director of USDA, APHIS, PPV
Project
• Stewart Bruce, GIS Instructor
• Arthur Freda, IT Support for USDA, APHIS, PPV and
cartoonist