standardization of environmental data and information - International ...

too difficult to deal with and were of no use for monitoring. In using
nematodes as an example, he was not implying that their behaviour was
typical for meiofauna, since copepods behaved completely differently.
Research methods
Describing how biologists worked with these small, multicelled
animals, he said samples were collected with a core sampler. Specimens
not taken with a high quality meiofauna sampler were dubious, and even
box cores were not good enough for meiofauna. Experiments had shown
that an average of 60% of the meiofauna were lost with a box corer, the
problem being that this proportion was variable. Next, using tube samples
from a bionic multiple corer that had been brought back on the boat, the
sediment was sectioned, usually at one-centimetre intervals. The only part
of the sediment normally studied was the top 0-1 cm, because working with
meiofauna was labour intensive and looking through the whole core would
mean that fewer samples could be studied. Investigating this top
centimetre probably gave a good idea of what was going on, because more
organisms lived in that interface area than in any other segment. This
might be a bad assumption but it had now become standard. Once
sectioned, the cores were shoved into plastic bags with a preservative --
formalin for morphology or alcohol for genetic work. Nothing else could be
done on the boat; the materials went into boxes and then back to the
museum.
In the museum, the first step was to separate the animals from the
sediment. This non-trivial process could not be automated; it was a
technical rather than a scientific task but it was labour intensive and skilled.
The technician performing this work took about one week per sample.
Floatation methods were used to separate the animals from most of the
muck, but finally each animal had to be picked out by hand on a titanium
wire. Each worm, about 0.5 millimetres long on average, was then placed
on a watch glass of glycerine alcohol (glycerol). The glycerine alcohol was
put into a desiccator for a day or two, leaving a watch glass full of
nematodes. These would have to be mounted on slides before any work
could be done with them. With shallow water collections, all the animals
could be put on one slide, but that did not work with deep-sea samples
because their taxonomy was unknown. The animals had to be used as a
voucher collection, because the species could not be identified from a book.
Usually, about ten were mounted to each slide; one per slide would be
better, but if a core contained 3000 animals, that many slides would be a
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