Plant Mapping

Gordon Wells (wells@ic.upc.es)
Wed, 6 Mar 1996 11:21:49 UTC+0100

Concerning the recent plans to include geographical
information in the CP Database, on 6 March 1996,
Rick Walker wrote:

> The CIRCLE entry is a latitude and longitude plus a radius.

> The POLY entry is a three or more x,y coordinates, in this case
> delimiting a triangular distribution region.

> For a poacher to exploit the information, they would need to search
> a 100 square km area to find the exact site. For an even rarer species,
> the GRID could be set to 50km resolution.

I see a potential problem with this. When you want to place a
circle or triangle over a particular habitat, where will you
choose to place the center of the circle ? The really only
logical place is right in the center of where the plants grow.
This means that anyone wanting to find plants in that circle
would probably find something if they just went right to
the center. This would be especially true for the rarer
species - in fact, the rarer the species, the more likely it
would be to find plants right in the center of the circle.
Of course, the exception would be habitat areas with "holes"
in the center, or where there are a few very small sites
scattered around different points in the circle. Of course,
you could always offset the circle a bit in order to be
misleading, but this would just add inaccuracy to the
geographical data.

So, I don't see how specifying the areas by single circles
and triangles is going to help make it any more difficult
to find the plants. Perhaps this is a silly point, but if
you compare this idea with what you generally see in the
habitat maps of CP books (large, irregularly shaped areas),
you can see the difference.

Gordon Wells
Instituto de Cibernetica
Diagonal 647, planta 2
Barcelona 08028
SPAIN