standardization of environmental data and information - International ...

cm. Those two conditions made for a random distribution of the photo
profile – an important factor for data processing. The time intervals
between frames were from 10 s to 1 min, mostly in the range of 17-20 s.
Depending on distance to the bottom, each photograph covered between
3.8 and 4.4 m 3 . Printed on each bottom image were the frame number,
relative time and distance to the bottom. During the photo surveys, the
underwater navigation system gave a co-ordinate for the apparatus every
two minutes.
In the laboratory, each frame was converted to digital format, mostly
.tif files, and saved on compact disks. With these digital images from
photographs, it was possible to create a deep-sea photo database. Mr.
Melnik showed a sample photograph depicting a disturber track about 10-
12 cm high, with a holothurian (sea cucumber), probably 25-30 cm long,
crossing the track (see figure 1 above).
Suggestions for environmental baseline studies
Outlining proposed guidelines for environmental baseline studies,
Mr. Melnik said the study area should be a polygon about 4-5 kilometres²
that resembled a mine site in its physical, chemical and biological
characteristics, as determined by photo and television profiles and
bathymetric and echo-sounder surveys. Russian researchers had always
tried to select clear sediment areas with few or no manganese nodules,
because the disturber device needed a clear area to create a big plume of
sediment. Second, at least 30 sediment samples should be taken within
the polygon to ascertain the number and taxonomic types of meiofauna and
macrofauna and the chemical characteristics of pore water, and to perform
geological and gravimetric analysis of the sediments. During the last
Russian cruise there had been 30 stations, 12 using a multicorer and 18
using a box corer. As multicorers could not be used to collect macrofauna,
a large number of box-core samplers were needed; perhaps 30 were not
enough.
To collect macrofauna, he suggested the use of a 0.25m² box corer,
with the resulting sediment core separated into three layers at the 0-2, 2-5
and 5-10 cm levels, then washed with an elutriation device and a 0.3-mm
sieve, fixed using 4% formaldehyde and 80% alcohol, and stained with rose
Bengal. The specimens should be sorted and initially classified according to
the higher taxa – class, order and family. The sorted specimens should be
stored in 80% alcohol as collection material, which could then be moved to
other laboratories for study and possible species identification. The same
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