There are a growing number of human activities occurring within the marine environment. Concern over the possible impacts of these activities on the marine and coastal environment has led to the development of national, regional, and global commitments that aim to preserve, and, where possible, to mitigate impacts on marine environments (UKMMAS 2010).
Different human activities exert a variety of pressures and these pressures will, in turn, have different levels of impact on habitats and species. To enable management of these impacts, we need to better understand how human activities and biodiversity interact spatially and temporally. We can then assess the sensitivity of the habitats and species that are exposed to these activities, and thus the associated pressures. When combined, exposure and sensitivity provide an indication of a habitat’s ‘vulnerability’ to impacts.
To support this vulnerability assessment approach, JNCC are developing methods for creating geospatial pressure datasets for use at a regional and national scale. These datasets are created using a GIS to delineate their spatial extent and all activities that are known to exert the pressure are considered. In the UK one of the priority pressures on benthic habitats is Physical Damage – “Habitat structure changes - abrasion & other physical damage” hereafter referred to as ‘abrasion’, which is described as the “disturbance of sediments where there is limited or no loss of substrate from the system”.
This layer depicts figure 2 - Subsurface swept area ratio for UK vessels (≥15m) in 2012 - from JNCC report 515 available via http://jncc.defra.gov.uk/page-7358