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Methodologies
METHODOLOGIES
Fragmentation metrics
Effective mesh size, largest patch index and patch-size power law.
Method
Effective mesh size (Jaeger 2000): m = Σ aᵢ² / A, the area of the patch you would land in if you dropped a random point on mangrove. Largest patch index = largest patch ÷ total area × 100.
Power-law exponent α uses the maximum-likelihood estimator of Clauset, Shalizi & Newman (2009) for patches above a minimum size x_min.
How to interpret it
A bigger effective mesh size means a less fragmented landscape. A heavy-tailed size distribution (small α) means a few very large stands carry most of the area.
Limits. Patches cut by the mapping boundary are counted as separate patches.
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