La Mucuy Plot A
Relief and tree basal area visualization
by Deanna Sanchez
Relief of hillside created from relative elevation at 11x11 grid points
by the Spline function in Arc View. The lowest value (-8.137) was added
with + sign to each point to obtain the map referenced to a zero datum
in the lowest point (NE corner). Click here to see
the data.
Tree basal area was added as cylinders proportionally for each grid
cell. The number of trees per cell ranges from 3 to 11. Forest plot is
32 m x 32 m.
Notes:
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The dates correspond to February 1997 days: 19,20,21,22 and 25,26,27,28
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The site is near the City of Merida which is approx 80 38' N and 70 14'
W
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The Spline function extends the edges of the "hillside" when it interpolates
the elevations, yet the vertex points still retain the exact elevation
points. (For example, the far bottom right vertex is still at elevation
zero; spline has extended the coverage further down to a "negative 5".)
There is a way to "clip" the extending portion, if needed.
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Arc View does not allow to make the cylinders more "tree-like", e.g. to
change diameters at some height to mimic tree crown. Trees are shaded "on
themselves", but trees do not cast a shadow on the other trees (or the
ground) using ArcView. Further visualization enhancements will require
different software.
Relief only
Grid points (from the north) and Relief
from excel worksheet
Relief using ArcView:
Relief and trees: 12 images obtained by combining four angles
of view (N, S, W, E) with three different times of the day (11 am, 1 pm
and 3 pm). In addition, views from above are provided. Tree height was
assumed to be 15 m and scaled with respect to plot size 32x32 m.
