Impacts of Sea Level Rise on Fishes
Insightful
GeoInformatics
www.insightfulgeo.
ca
Source: IPCC, 2013
Sea level is expected to rise past historical levels in the next 100
years.
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Sea
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Year
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SL 1 SL 1.5
Recent study show that sea level rise can drown and shrink
wetlands because of coastal squeeze.
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Projected distribution of salt marsh areas at Year 2100 sea levels (m)
Source: Torio & Chmura, 2013
How will a shrinking marsh surface affect fish habitats within the
salt marsh?
Image source: http://ian.umces.edu/imagelibrary/displayimage-4192.html
To examine the impacts sea level rise on salt marsh as fish habitats,
the size, configuration and connectivity of salt marsh patches were
evaluated.
Patch size and configuration Connectivity
Results indicate that at moderate sea level rise, salt marsh area
increased resulting in more available fish habitats.
-At high sea level, 40% of the future marshes will be in
private properties!
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ES
LI
Constant Accretion
Accretion = SLR
Carrying Capacity (ESLI)
Not only the size but also the variability of marsh patches increased
with moderate sea level rise.
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Are
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ha)
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Are
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Sea Level (m)
Constant Accretion
Accretion = SLR
Patch size standard deviation Mean Patch Size
Apart from habitat size and variability, complexity of marsh edges
which provide refuge for small fishes also increased.
Edge Density Fractal Dimension
Furthermore, moderate flooding from sea level rise increased
connectivity between habitat patches.
Summary and conclusion
Moderate sea level rise resulted in
expansion of fish habitats. Moderate means
sea levels not exceeding 1 meter. Sea
levels exceeding this threshold resulted in
reduced habitat size, configuration and
fragmentation.