Teaching with Technology

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Spatial Data Analysis The accurate description
of data related to a process operating in space,
the exploration of patterns and relationships in
such data, and the search for explanation of such
patterns and relationships
Spatial Analysis vs. Spatial Data
Analysis Spatial Analysis what is here, and
where are all the Xs ??? Spatial Data Analysis
observation data for a process operating in
space and methods are used to describe or explain
the behavior, and/or relationship with other
phenomena.
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Types of Metics

• Area Metrics
• Patch Density, Size and Variability
• Edge Metrics
• Shape Metrics
• Core Area Metrics
• Nearest-Neighbor Metrics
• Diversity Metrics
• Contagion and Interspersion Metrics

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Landscape Ecology

• Structure the spatial relationships among the
  distinctive ecosystems or elements
• Function the interactions among the spatial
  elements
• Change the alteration in the structure and
  function of the ecological mosaic over time

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Fragstats McGarigal, K. and Marks, B.J. 1995,
Fragstats Spatial Pattern Analysis Program for
Quantifying Landscape Structure. General
Technical Report, PNW-GTR-351. Portland, OR, U.S.
Department of Agriculture, Forest Service,
Pacific Northwest Research Station, 122p.
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Terms

• Landscape a mosaic of patches.
• Patch the basic element or unit of the
  landscape defined relative to the phenomenon,
  that are dynamic and occur at multiple ecological
  scales with unique and meaningful boundaries
• Matrix the most extensive and most connected
  element dominating the function of the landscape
• Class a category or type of patch
• Ecological Scale both the Extent (area within
  the landscape boundary) and Grain (the size of
  the units of observation) defining the dynamics
  of the phenomenon.

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Landscape Structure Physiognomy / Pattern

• Composition The presence and amount of each
  element type without spatially explicit measures.
• Proportion, richness, evenness, diversity
• Configuration The physical distribution in
  space and spatial character of elements.
• Isolation, placement, adjacency
• some metrics do both

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Area Metrics

• Absolute Metrics
• Total Area (TA)
• Class Area (CA)
• Relative Metrics
• Percent
• (extent), or land percent of total occupied
  by each class
• (LSIM) Landscape similarity Index
• For each element LSIM extent
• Largest (LPI), Smallest (SPI)

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Density, Size and Variability

• Number of element (NE) or Patches (NP)
• Density of Element - patch density (PD) number
  of elements on a per unit basis
• Mean Element or Patch size (MPS)
• for the landscape
• for the class
• Patch size coefficient of variation (PSCV) a
  measure of relative variation, the difference in
  patch size among patches, (I.e. variability as a
  percentage of the mean).

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Edge Metrics

• Total Edge (TE) and Edge Density (ED), for all
  classes and by class
• Perimeter (PERIM) by patch
• Edge Contrast Index (EDGECON) difference across
  a boundary
• total edge contrast
• mean edge contrast
• area-weighted mean edge contrast
• contrast-weighted edge density

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Shape Metricsperimeter-area relationships

• Shape Index (SHAPE) -- complexity of patch
  compared to standard shape
• vector uses circular raster uses square
• Mean Shape Index (MSI) perimeter-to-area ratio
• Area-Weighted Mean Shape Index (AWMSI)
• Landscape Shape Index (LSI)
• Fractal Dimension (D), or (FRACT)
• log P 1/2Dlog A P perimeter, A area
• P sq.rt. A raised to D, and D 1 (a line)
• as polygons move to complexity P A, and D -gt 2
• A few fractal metrics
• Double log fractal dimension (DLFD)
• Mean patch fractal (MPFD)
• Area-weighted mean patch fractal dimension
  (AWMPFD)

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Core Area Metrics

• The area within a patch beyond a buffer or
  edge distance
• Corresponding metrics with those dealing with
• Density
• Size
• Variability

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Nearest-Neighbor Metrics

• The distance from a patch to the nearest
  neighboring patch of the SAME type
• Nearest-neighbor distance (near) just distance
• Proximity index (PROXIM), using a search radius
  distinguishes sparse distribution from complex
  clusters

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Diversity Metrics

• Influenced by the compositional and structural
  components of diversity
• Richness the number present
• Evenness the distribution of area among
  different types
• Shannons Diversity Index (SHDI) magnitude not
  meaningful, a relative index
• Simpsons diversity Index (SIDI) the probability
  that any types selected would be different
  (also a modified version)

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More on Diversity

• Patch Richness (PR) and Patch Richness Density
  (PRD)
• Evenness or, the distribution of area among
  types
• The compliment is Dominance
• Evenness 1- dominance
• Shannons evenness index (SHEI)
• Simpsons Evenness Index (SIEI)

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Contagion, Interspersion and Juxtaposition

• When first proposed (ONeill 1988) proved
  incorrect, Li Reynolds (1993) alternative
• Based upon the product of two (2) probabilities
• Randomly chosen cell belongs to patch i
• Conditional probability of given type i
  neighboring cells belongs to j
• Interspersion (the intermixing of units of
  different patch types) and Juxtaposition (the mix
  of different types being adjacent) index (IJI)