Landscape Structural Metrics
Sibyl Brunner
Ana Stritih
Vincent Cohen
Prof. Dr. Adrienne Grêt-Regamey
Landscape Structural Metrics
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Lang und Blaschke, 2007
Area metrics
Patch level:
Patch Size (PS)
Class level:
Mean Patch Size (MPS)
Patch Size Standard
Deviation (PSSD)
= spread of patch sizes
Patch Size Coefficient of
Variation (PSCV)
= standardized spread of
patch sizes
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MPS =
n
j=1 a ij
ni
n
j=1
PSSD =
PSCV =
n = number of patches, a = area
n
j=1 a ij
aij −
ni
ni
𝑃𝑆𝑆𝐷
∙ 100
𝑀𝑃𝑆
2
Core area metrics
Patch level:
Core Area (CA)
= core area of a patch
Core Area Index (CAI)
= Percentage of the patch that
is comprised of core area
Landscape level:
Cority (CY)
= Fragmentation with
respect to a core area
distance
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𝑁𝑃 − 𝑁𝐶𝐴𝐼=0
𝐶𝑌 =
𝑁𝐶𝐴
NP = number of patches
NCAI=0 = patches without core area
NCA = number of core areas
Edge metrics
Patch/class/landscape level:
Total Edge (TE)
= total edge length
Edge Density (ED)
= edge length per area
Mean Patch Edge (MPE)
= mean edge length per patch
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Tasks
• Application of the landscape metrics you have learned
today in the lecture
• Using GIS extension but also GIS «normal» functions to
calculate
 Very short introduction into
«patch analyst»
 Work through the questions
 15 minutes before official end
of the lecture: discussion of
selected questions
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Discussion
Area metrics
• Which units do the metrics PS, MPS, PSSD and PSCV have?
• Compare the MPS, PSSD annd PSCV of individual wetland types. What information
doe the metrics convey, what do you observe?
Core area metrics
• What do the columns denote when calculating CA in Patch analyst?
• Which untis do the metrics CAI and CY have. What information doe the metrics
convey, what do you observe?
Edge metrics
• Calculate TE, ED and MPE for the three landscapes. How do the results relate to
your observations?
• Remove the unnatural borders. How does it affect your results?
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Discussion
Area metrics
• Which units do the metrics PS, MPS, PSSD and PSCV have?
• Compare the MPS, PSSD annd PSCV of individual wetland types. What information
doe the metrics convey, what do you observe?
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Discussion
Core area metrics
• What do the columns denote when calculating CA in Patch analyst?
Multiple cores detached
• How to calculate CAI and CY in Patch Analyst?
• Which units do the metrics CAI and CY have? What information do the metrics
convey, what do you observe?
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Discussion
Edge metrics
• Calculate TE, ED and MPE for the three landscapes. How do the results relate to
your observations?
Agriculture
Conifer
mixed
• Remove the unnatural borders. How does it affect your results?
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