standardization of environmental data and information - International ...

If all the animals on the bottom were wiped out, would the fish
care? Rex noted that at abyssal depths there were many fewer fish. To
estimate the diversity of the fish megafauna in the abyss, he had had to
lump together a huge number of trawl samples to get enough individuals.
All food in the abyss, except for chemosynthetic communities, was extrinsic
in origin, sinking from the surface in a variety of forms. The reason for the
marked decline in standing stock with depth was that less food arrived
there.
It could not be said, Smith observed, that the animals in the water
column were independent of those on the seafloor. Though there were no
strong linkages between the abyssal seafloor and the euphotic zone, many
species that moved had large vertical ranges. For example, deep-sea
amphipods that fed on the seafloor had been trapped 1 or 2 km above the
seafloor in the water column, indicating that their life history and feeding
biology were linked to the bottom. Citing another example of interaction,
Rex recalled that the holotype of one large deep-sea crustacean was known
from the stomach contents of a gull.
Smith cited a study by Ken Smith 39 in which upside-down sediment
traps that captured rising particles had found an upward flux that was about
40 percent of the downward flux. There was also evidence that the
amphipod mentioned by Rex that had been found in the gut of a sea gull
stored its food energy in droplets of lipids that caused its body to float to the
surface when it died. This had been a concern for people investigating
radioactive waste in the deep sea, where even a little bit of material rising
from the bottom might cause serious contamination. Though the euphotic
zone would not die if life on the seafloor were wiped out, and the tuna and
whales probably would not care, linkages did exist.
Species identification and sampling technology
Given the fact that science was far from knowing all the species in
the deep sea, could just the macrofauna in the CCFZ be described before
mining started? Otherwise, nobody would know whether a species had
been made extinct and non-governmental organizations might take up this
argument to oppose mining.
Rex replied that conducting a taxonomic synthesis of publications
and/or a large biotic survey would be ambitious. He did not think that
would be necessary to gauge the impact, however. Consistency in
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