Hi T. Bar

You might consider the OBIS extensions for Darwin Core since you are concerned with marine stuff.

http://iobis.org/obis/obis.xsd

SampleSize:  the size of the sample from which the collection/observation was drawn.  It can be a volume (e.g. for a phytoplankton sample), a linear distance (e.g. for a visual transect or net haul), a surface area (e.g. for a benthic core), etc.  This field must also include the units, e.g. 200 mfor a transect, or 0.25 m^2 for a benthic grab (use ^ to denote a superscript).  Note that when multiple collections/observations are reported from the same physical sample, a code identifying the sample can be placed in the Field_Number field to allow all collections/observations from a single sample to be connected.  

IndividualCount is a count of specimens (e.g. not a count of species).  If you want to indicate multiple species, then you would have a record for each along with the identification and the count  of individuals of that species.

So in the OBIS schema you have:

ObservedIndividualCount: The number of individuals (abundance) found in a collection/record event.

Cheers,

Tim

On 28 Nov 2008, at 17:05, bar tomas wrote:

Sorry if this question is misplaced in this discussion list, but I haven't been able to find a mailing list on the conceptual aspects of Darwin Core.

 

I am interested to know if there are any recommendations on how to represent abundance in Darwin Core. I have seen some datasets using IndividualCount and SampleSize. For instance, for a fishing survey, would you use IndividualCount for the number of species in a catch, and SampleSize for the distance towed?

 

Thank you very much

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