Dear friends, reprints of the papers quoted below (see abstracts at the
bottom of this message) can be delivered on request.
1/ POLYCHAETE PATTERNS FROM AN OCEANIC ISLAND IN THE EASTERN CENTRAL
ATLANTIC: LA GOMERA (CANARY ARCHIPELAGO) (reprints already available).
Herrando-Pérez S, San Martín G & Nuñez J, 2001.
Cahiers de Biologie Marine 42(3), 275-287.
KEYWORDS: Polychaete, Diversity, Reproduction, Dispersion, Oceanic Islands,
Biogeography.
2/ RECOVERY PATTERNS OF MACROBENTHOS AND SEDIMENT AT A CLOSED FLY-ASH
DUMPSITE (reprints available from November 2001).
Herrando-Pérez S & Frid CLJ, 2001.
Sarsia 86(4/5). In press.
KEYWORDS: Recovery, Fly-ash, Dumping, Sediment dynamics, Macrobenthos,
Trophic structure, Opportunism.
3/ THE CESSATION OF LONG-TERM FLY-ASH DUMPING: EFFECTS ON MACROBENTHOS AND
SEDIMENTS (just a few reprints left).
Herrando-Pérez S & Frid CLJ, 1998.
Marine Pollution Bulletin 36(10), 780-790.
KEYWORDS: Fly-ash, Recovery, North Sea, Northumberland, Macrofauna.
Best regards. Salva
<salherra at ctv.es>
1/ POLYCHAETE PATTERNS FROM AN OCEANIC ISLAND IN THE EASTERN CENTRAL
ATLANTIC: LA GOMERA (CANARY ARCHIPELAGO)
Abstract: The polychaete macrofauna along the shallow sublittoral of La
Gomera (Canary Islands, eastern Central Atlantic) was surveyed during the
summer 1995 with a 0.01 m2 van Veen grab. Sampling resulted in a moderate
number of specimens per sample unit, which influenced the assessment of a
and b diversity. Diversity patterns followed sediment and hydrographic
gradients between the north of the island (coarse sandy bottoms directly
exposed to the open ocean), and the south (sheltered fine sandy bottoms).
Of the 81 taxa recorded, two species were new to science, while a further
24 species were cited for the first time to the Canaries. Spionids (46 % of
faunal density), syllids (14 species) and onuphids were locally well
represented and their distribution responded to life history features and
sediment types. Polychaetes with a wide biogeographic range and relying on
meroplanktonic phases for dispersal predominated. Factors controlling the
access of polychaete populations to oceanic islands are discussed,
including the role of major surface oceanic currents in the dispersion of
larvae and reproductive adaptations of species.
2/ RECOVERY PATTERNS OF MACROBENTHOS AND SEDIMENT AT A CLOSED FLY-ASH DUMPSITE
Abstract: Almost 14 million tonnes of fly ash from the Blyth Power Station
were disposed of at a sublittoral dumpsite off the NE of England from 1956
to December 1992. The recovery of the sediment and the macrofauna at two
impacted areas was assessed against ambient, control conditions by means of
a 0.1 m2 van Veen grab. An area of 27 km2 was covered by three sediment
surveys (August 1993, March & October 1994) and three faunal surveys
(January 1994, September 1993 & 1994). Sediment trends were analysed by
means of PCA and mapping, whereas species patterns were contrasted through
trophic and a-diversity measures. Signs of recovery were observed over the
whole study period, though dramatic increases in a-diversity and the
recuperation of the impacted subsurface detritivore species only occurred
between winter and summer 1994 simultaneous with a 80 % loss of fly-ash in
the sediments at the dumpsite. Macrobenthic recolonisation involved
opportunists, ambient dominants, and taxa experiencing regional expansion.
Species replacement and change in dominance characterised the succession
towards ambient conditions, and were still obvious by the Summer 1994 when
over 40 % of the background density had been reached. Coarse wastes derived
from dumping, both fly-ash aggregates and clinker, have persisted in
inshore areas impacting this, normally, soft-bottomed system. The rate of
change in sediment characteristics at the dumpsite could imply that
considerable amounts of waste remain buried under a layer of sand and could
surface in the future, re-setting the on-going process of recovery.
3/ THE CESSATION OF LONG-TERM FLY-ASH DUMPING: EFFECTS ON MACROBENTHOS AND
SEDIMENTS.
Abstract: Four decades of continual fly-ash disposal off Northumberland
(UK) ended in December 1992. Quantitative sampling of the sediment and the
macrobenthos was undertaken in the Summer 1993 over 27 km2 of seabed
covering the Blyth fly-ash dumpsite and the surrounding area. The offshore
portion of the region surveyed bore only traces of fly-ash particles, waste
being confined to the region shallower than 45 m. There, disposals have
changed local sedimentary conditions increasing the spatial patchiness of
sediment types and altering silt-clay dynamics. Inshore of the dumpsite,
substrata affected by long-term tipping have effectively become an
artificial reef due to the cementation of the waste. The seabed within the
designated dumpsite was still composed of pure fly-ash , resulting in
macrobenthic densities and species richness markedly lower than control
areas, though higher than in a previous survey in 1988. At the dumpsite,
47-66% of the species had only or two representatives and juveniles made up
47-88% of the individuals. Additional faunal impoverishment occurred where
pebbly clinker and aggregates abounded. Nine months after cessation of
dumping recovery was essentially dependant on the decrease in the
concentration of the waste and will proceed as the gradual fertilization of
the sediments occurs.
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