dot maps

[Russ Spangler]

Bryan raised a good point below when stating that programs like MapInfo
aren't flexible for fine-tuning dot maps.  I've been using ArcView to
generate dot maps based on GPS data and lat/long data from gazeteers, and
have been able to get points located very accurately.  Arcview allows one
to zoom in and maintains precision of the specimen location so at small
scale, very accurate dot maps are produced.  I think producing a variety of
scales of dot maps for different needs may be a useful solution for
presentation. Meaning, for taxa that are obviously widespread and localized
points don't give much more information than "blobs" drawn to represent a
generalized range, kep the map scale large.  For taxa that are very locally
distributed, a scale small enough to show individual localities (and
perhaps any important environmental factors mapped simultaneously) would be
the best to present.  The increasing amount of geospacial data for things
like soil type, water availability, etc. that are available as ArcView
layers, these small scale maps will be invaluable for determining the
variables that ultimately affect taxon distribution and can even be useful
in drawing range "predictions" based on environmental similarities to
specimen collection localities.  If you don't have ArcView, but know
someone who does and can show it to you, check it out.  It seems to be a
very powerful way to not only map specimens, but to keep track of data
associated with each one that can, as mentioned below, be coded as
characters in interactive keys.

Cheers,
Russ Spangler
>
>Ideally it would be nice if mapping programs (such as MapInfo) could use the
>same flora distribution data to zoom in on distributions as the scale became
>smaller. Theoretically it could then be possible to fine-tune the
>distribution patterns of individual collections within the area of a 100 km
>wide dot.  This geographic and spatial data could then presumably be
>able to link up with on-line interactive identification and information
>retrieval programs.

----------------------------------------------------------
Russ Spangler                    spangler at oeb.harvard.edu
Harvard University Herbaria      http://www.fas.harvard.edu/~spangler
22 Divinity Avenue               Herbaria room 315
Cambridge, MA  02138             (617) 496-1566
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