Physical and biological impact of marine aggregate extraction along the French coast of the Eastern English Channel: short- and long-term post-dredging restoration

  • Published source details Desprez M. (2000) Physical and biological impact of marine aggregate extraction along the French coast of the Eastern English Channel: short- and long-term post-dredging restoration. ICES Journal of Marine Science, 57, 1428-1438.


This study is summarised as evidence for the following.

Action Category

Cease or prohibit aggregate extraction

Action Link
Subtidal Benthic Invertebrate Conservation
  1. Cease or prohibit aggregate extraction

    A before-and-after, site comparison study in 1994–1997 of eight sites in one area of sandy and gravelly seabed in the English Channel, off the coast of France (Desprez 2000) found that 16–28 months after ceasing aggregate extraction, invertebrate species richness, abundance, and biomass appeared to have increased, and had become more similar to that of adjacent natural sites where extraction did not occur. Data were not statistically tested. After cessation, species richness at extraction sites increased and appeared to be more similar to natural sites (before: 37% that of natural sites; after 16 months onwards: >100%). Increases were also observed for biomass (before: 17%; after 16 months: 35%; after 28 months: 75% that of natural sites) and abundance (before: 14%; after 16 months: 56%; after 28 months: 57% that of natural sites). Aggregate extraction took place between 1980 and 1994. In 1994 (prior to cessation), 1996 (after 16 months) and 1997 (after 28 months), invertebrate communities were surveyed at five extracted sites and three natural sites (1 km outside the extraction area). Samples were collected using a sediment grab (0.1 m2; three samples/site/year) and invertebrates (>1 mm) identified, counted, and dry-weighed.

    (Summarised by: Anaëlle Lemasson)

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