Rugosity, "f"r, is a measure of small-scale variations or amplitude in the height of a surface,
where "A"r is the real (true, actual) surface area and "A"g is the
geometric surface area. [GoldBookRef|title=roughness factor (rugosity) "of a surface"|file=R05419]
Rugosity calculations are commonly used in marine science to characterize seafloor habitats.
Ecology: As a measure of complexity, rugosity is presumed to be an indicator of the amount of available habitat available for colonization by benthic organisms (those attached to the seafloor), and shelter and foraging area for mobile organisms.
Geology: For marine geologists and geomorphologists, rugosity is a useful characteristic in distinguishing different types of seafloors in remote sensing applications (e.g., sonar and laser altimetry, based from ships, planes or satellites).
Oceanography: Among oceanographers, rugosity is recognized to influence small-scale hydrodynamics by converting organized laminar or oscillatory flow into energy-dissipating turbulence.
Coral biology: High rugosity is often an indication of the presence of coral, which creates a complex surface as it grows. A rugose seafloor's tendency to generate turbulence is understood to promote the growth of coral and coralline algae by delivering nutrient-rich water after the organisms have depleted the nutrients from the envelope of water immediately surrounding their tissues.
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