Transcript 3_01_04_Kilifi

Vegetation Change
Detection in a Low
Lying Atoll Island
Kilifi
Postgraduate climate change
University of the South Pacific
Focus
• COMMUNITY PERCEPTION OF
IMPACTS OF ENVIRONMENTAL
AND CLIMATE CHANGE WITH
SPECIFIC FOCUS ON
VEGETATION CHANGES IN LOW
LYING ATOLL ISLANDS: A CASE
STUDY OF NANUMEA, VAITUPU
AND FUNAFUTI IN
• TUVALU
Approach
• Use of individual’s perception
living the study area as a tool to
obtain useful information related
to the topic;
• Use of GIS and remote sensing to
perform mapping vegetation
change with a scale of 1:10,000
Water
security
Biosecurity
Food
Security
Fires
Bush
Purpose for Vegetation Change
Detection
To determine the potential of using
remote sensing in the context of
vegetation change using
photography with a scale of
1:10,000 in low lying atoll islands
within a period of three years
Vegetation Change
Detection:
• Mapping (satellite image) for year
2003;
• Mapping repeated for the 2006;
• Overlay of both mappings;
• Highlighting change;
Geometric Correction
Essential
1. Image enhancement
To increase contrast between the
vegetation types Image
enhancement
2. Vegetation interpretation
Digitizing
Interpretation key
Dense coconut
A clear forest among
vegetation
Mangrove vegetation
Raster Data - Vector Data
• vector data contains
x, y co-ordinates,
direction and
distance to the next
point, annotation is
added to the polygon
• raster data contains
the annotation and x,
y of is centre
Vector to Raster
TAB
DXF
ANNOTATION
LAYER
ERDAS RASTER
Overlay Analysis 1:10,000
2003
2006
Change within 3 Years
Vegetation 2003
Vegetation 2006
Comparison 2003 & 2006
2003
2006
Vegetation 2003
Vegetation 2006
Latest Mapping
See SOPAC and LRD
Website (soon)
Area Calculation Vegetation
Cover 2003 – 2006 (Nanumea)
Conclusion
• Changes in vegetation detection were
detected but very small simply
because the period is too short.
• Mapping vegetation change of
1:10,000 scale is possible in a low
lying atoll islands within a 3 years
period;
• Measured variables can be used later
for future research;
Thank You