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(GSFM)- Applications for Ocean Conservation and Management

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(GSFM)- Applications for Ocean Conservation and Management A New Global Seafloor Geomorphic Features Map - Applications for Ocean Conservation and Management Miles Macmillan-Lawler, Peter Harris, Elaine Baker, Jonas Rupp GRID-Arendal, Geoscience Australia, Conservation International Why Map Seafloor Geomorphology? • Seafloor geomorphology can be mapped at global scale using existing data • Is a useful surrogate for biodiversity at the global scale. i.e Seamounts have a different suite of species to Abyssal Plains • Support improved management of the marine environment (eg MSP, feature inventories) • Can be built upon using other physical and biological data Heezen and Tharp, 1960’s Global Map 1977 Interpretation of seafloor morphology – drawn by hand! From Agapova et al. (1979) Improved digital bathymetry now available! Geomorphic Feature Interpretation • SRTM30Plus v7 + other data • Features defined based on shape, slope, rugosity and TPI etc. • Combination of automated algorithms and expert interpretation • Minimum feature size mapped ~10 square kilometres How do we map seafloor geomorphic features? bathymetry contours Slope TPI IHO Categories Global Seafloor Geomorphic Features Map Some interesting statistics • 131,192 separate polygons • 10,234 seamounts and guyots • Passive margin continental shelf width nearly 3x that of active margins • Polar submarine canyons are twice as large • Large rift valley segments are associated with slow spreading rates Application of the GSFM for management • Pacific – PACIOCEA & EPOG • Global MPA representativeness • VME identification • CCZ assessment PACIOCEA project area Features in the PACIOCEA project area features in the PACIOCEA project area What summarises the PACIOCEA project area • Small amount shelf and slope • Large amount of abyssal habitats, esp hills and mountains • Escarpment, seamount, guyot, ridge trough trench and plateau all represented above global average Classification of seamounts and guyots and canyons • Seamounts and guyots important features for biodiversity. • PACIOCEA project area contains 2784 seamounts, 93 guyots. • Classified based on geomorphometric and physical parameters Seamount and guyot classification Parameter Classes Relevance Height Small (< 2000 m) Larger seamounts cover more depth ranges and thus Large (> 2000 m) potentially more species habitats Peak Depth Shallow – photic (< 50 m) Seamounts that extend into the photic or mesophotic Shallow – mesophotic (50 – 150 m) zones will support different species that those that do Medium – fishable depths (150 – 2000 m) not. Shallow seamounts (less than 2000m) may be Deep (> 2000 m) exposed to fishing pressures using current fishing techniques. Seamount type Seamount Guyots have a truncated peak and may offer different Guyot habitat at the peak depth range than an equivalent height seamount. Salinity No significant variation (not used) No variation observed in the deep waters of this region Dissolved oxygen Low (<1 ml/l) Low dissolved oxygen (< 1ml/l) can inhibit some Adequate (>1 ml/l) organisms Temperature Cold (<4 degrees) The temperature range 4-12 degrees Celsius represents Cool (4-12 degrees) the temperature range for the cold water coral Lophelia Warm (>12 degrees) pertusa Maximum Weak (< 0.125 ms-1) Stronger maximum bottom currents are likely to lead to Bottom Current Strong (> 0.125 ms-1) greater disturbance and promote a different suite of species. Physical Data Seamount and guyot classification • 28 different categories of seamount • Only 9 categories have 50 or more seamounts Seamount and guyot classification Global MPAs – WDPA August 2013 version CDB - Aichi Target 11 By 2020, at least 17 per cent of terrestrial and inland water areas and 10 per cent of coastal and marine areas, especially areas of particular importance for biodiversity and ecosystem services, are conserved through effectively and equitably managed, ecologically representative and well- connected systems of protected areas and other effective area-based conservation measures, and integrated into the wider landscape and seascape. Global Status of MPAs • 3% of the oceans in MPAs • 97% of MPAs in EEZs • Majority of MPAs small • Majority of area from few large MPAs What features are represented in MPAs Abyssal Plains – Globally 0.7 % in MPAs Cape Verde Abyssal Plain Seamounts – Globally 2.9 % in MPAs Kelvin seamount in northwest Atlantic Trenches – Globally 8.5 % in MPAs Japan Trench Less than 3% of MPAs are in ABNJ Abyssal Plains Seamounts Trenches Representation in MPAs Globally what’s in and what’s not? • Feature representation ranges from 0.5 and 8.5% • Deep water features poorly represented • Representation of features varies in the different oceans • Features in ABNJ poorly represented Questions? [email protected] www.grida.no www.bluehabitats.org.
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