2016 SoE Marine Chapter - State and Trends - Seabed, slope (250 m - 700 m)

The Marine chapter of the 2016 State of the Environment (SoE) report incorporates multiple expert templates developed from streams of marine data. This metadata record describes the Expert Assessment "The state and trends of quality of habitats and communities – seabed, slope (250 m - 700 m)". The full Expert Assessment, including figures and tables (where provided), is attached to this record. Where available, the Data Stream(s) used to generate this Expert Assessment are accessible through the "On-line Resources" section of this record.

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DESCRIPTION OF HABITAT/COMMUNITY FOR EXPERT ASSESSMENT
This specified depth range (250 m to 700 m) defines the upper continental slope. This habitat is mostly an extremely narrow and typically steep ribbon of seabed beyond the shelf-break, but wider in places (GBR/Coral Sea and North-west Regions). Where it is narrowest and steepest in the Temperate East and South-east Regions, it is typified by sediment draped slopes interspersed with deep reefs, canyons and pinnacles (small seamounts); the latter two habitats are assessed separately. Considering its planar area, this habitat supports disproportionately highly productive fisheries and is therefore subject to high levels of pressure, particularly in the South-east and parts of the Temperate East, but less so in other regions.
Nearly 20% of the 200-700 m depth zone has been mapped with multibeam sonar (MBS) resulting in detailed bathymetry and acoustic backscatter maps of the seabed that enable the identification of deep reefs (Kloser & Keith 2013). The largest proportional coverage is in the southern regions, 75% in the South-east Region, and 36% in the South-west; coverage of the northern regions is