with VNS 3: GIS Basics
Part 8B. Placing Ecosystems
with Shapefile Objects
1. There are two ways to associate
the imported Pine Burn vectors with the Pine Burn
Ecosystem. One way is to copy each vector to the Ecosystem. This
is called hard linking and we've done it in previous tutorials.
It works great for a few vectors but is very tedious and inefficient
for thousands of them. The second way to associate vectors to
Ecosystems is to dynamically link them with a Search Query.
2. Go to the Land Cover Task
Mode. Expand the Ecosystems category and open the
Pine Burn Ecosystem. Go to the General page, Vector
Placement section, and select Link Operations .
3. Select Query and New
4. This will open the Search Query window, conveniently named Pine Burn.
The default filter is set to search the appropriate database
5. The Filter Criteria
page sets the conditions for searching the selected database
objects. We're going to use the shapefile attribute for ecosystem
type, ECOS, so select it from the Attribute Field
6. This is the Search Query for
finding Pine Burn vectors, so make the ECOS Attribute
value similar to pine burn. We could also use equal
to (=) and type in all caps, but similar avoids
problems caused by case issues in the original shapefile.
7. Go to the Database Editor. Select one of the DEMs to deselect
8. Go to the Search Query General page and Select Items
Now to test the Search Query.
9. The 9 Pine Burn vectors will
be selected in the Database Editor.
10. Open the Environment
to the Ecosystems page and Remove the Pine Burn
Ecosystem. This will restrict its rendering to vectors only.
Confirm the operation.
11. Save the project and render
a Main preview. The Pine Burn Ecosystem rendered within
all Pine Burn vectors.
12. We don't need the rendered
vectors in our view. Go the Database Editor
Properties page and select the 9 PB vectors if
they're not still selected. Click a Render checkbox to
deselect them all.
13. Save the project and render
14. The next thing we'll do is
use the species percentage attributes to drive the relative distributions
of Ecotypes within the Pine Burn Ecosystem. This is where Thematic
Maps come in. They map attribute values to Component values.
15. Bring up the Pine Burn
Editor and turn to the
Foliage page. The Overstory Ecotype will be the
dominant foliage species and the Understory Ecotype
will be the subdominant species.
16. Select the Overstory
Ecotype and turn to the Parameters page.
17. The Density is currently
a static value. Select Thematic Operations
and Create Thematic Map.
18. The Data page is where
we assign the attribute to the map. This is the Overstory, so
choose DOM_DENSIT from the Channel 1 dropdown list.
19. Back in the Ecosystem Editor, select the Understory Ecotype
and turn to the Parameters page. Select Density Thematic
Create Thematic Map.
20. Go to the Data page.
This is the Understory, so choose SUB_DENSIT from the
Channel 1 dropdown list.
21. Open another Main
view in the upper right quad. Save the project and render a preview.
The foliage densities are different now because they're using
shapefile attributes applied with Thematic Maps.
22. To display vector attribute
information in a render, right-click a forested area in the view.
A new Point tab will appear in the lower Scene-at-a-Glance pane. Here you'll see the vector name,
Attributes, Layers, and Components for those pixels within a
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