Exercise 6 - ArcView 8
Population Demographics Adjacent to
National Estuarine Research Reserves
Introduction
Part 1
Discussion
Part 2
Overview and the Coastal Context
Formatting Data for Analysis
Applying These Skills Elsewhere
Analysis and Display of Demographic Data
Discussion
Overview of Management Applications
Introduction
Understanding C-CAP Data
Part 3
Using C-CAP Data to Determine Impervious Surfaces
Discussion
Overview of Management Applications
Challenge
More Impervious Surface Calculations
Courtesy of
Written by OSU Marine Resources Mgmt. student Danielle Pattison
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Introduction: Skills Learned
Before beginning this exercise, please copy the data
directory \\sci-geo\geo265\data\ex6_coast to your student
working directory.
For this exercise, please turn in your lab report, including
answers to the questions posed in the exercise, as well
as the requested map layout. You will also hand in your
lab notebook. Again, please refer to the syllabus for
complete guidelines on writing these two documents.
After completing this exercise, you will have the skills to:
•
Use and understand Census data
•
Join and relate tables
•
Add and calculate table fields
•
Use various legend classifications and symbols
•
Create maps with multiple data frames
•
Use Coastal Change Analysis Program (C-CAP) data
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
Background
Goal
As a coastal resource manager, you are concerned with
the health and vitality of the nation’s coastal areas. With
coastal populations on the rise, you are particularly
interested in marine protected areas and how well they
are actually being protected from the human activities
outside their borders. In this exercise you will look at
National Estuarine Research Reserves (NERRs) in New
England and determine the areas of influence around
them. One of the challenges will be dealing with the
differences between natural and physical boundaries.
Physical processes may occur within natural boundaries,
but data is often available and management decisions
made in accordance with political boundaries. Therefore,
you will have both watershed and county boundaries to
work with. Once you have determined your areas of
influence, you will also need to find and incorporate
demographic data for those areas in preparation for
Exercise B.
After hearing the lecture and working through the
exercises, the student will be able to select features
based on location and create new layers containing
these data. The student will also be able to find and
understand census data, as well as being able to join
this and other tabular data to existing shapefiles.
Objectives
1. Reselect watersheds that intersect NERRs boundaries
2. Reselect counties that intersect and influence these
watersheds
3. Join the table containing population statistics and
demographic data for 2000 with the county shapefile
table
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 1: Formatting Data for Analysis
Tools to Use
Data
Summary of Process Steps
1. Select New England NERRs by Location – Create a
new shapefile of the NERRs that are located in the New
England states
2. Select Watersheds by Location – Create a new
shapefile of watersheds that intersect the New England
NERRs
3. Select Counties by Location - Create a new shapefile
of counties that have significant area within the chosen
watersheds
4. Find Census TIGER Data - Use the Internet to find
sites where 2000 Census TIGER data is available to
download
5. Join Table to Shapefile – Join the 2000 demographic
data to your county shapefile
4
New_England2.mxd
ArcMap document
states
Polygon layer of US
states
NERRs
Polygon layer of US
NERRs
ne_states
Polyline shapefile of New
England states
ne_watersheds
Polygon shapefile of New
England watersheds
ne_counties
Polygon shapefile of New
England counties
nerr_counties.lyr
Polygon layer file of counties
that intersect with NERRs
ne_dem_2000.dbf
DBF table of New England
census demographic data
Select By Location
Use this function to
select features based
on their location relative
to another feature
Join Data
Use this function to
append additional data
to a layer’s attribute
table
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
Did You Know?
1. Select New England NERRs by Location
Transparency
 To begin, start ArcMap
. When prompted, select to start the program with an existing
map, navigate to the ex6_coast data directory in your student working directory and select
the New_England.mxd ArcMap document file.
 Turn on the NERRs layer.
Notice that the NERRs layer, showing the nation’s estuarine research reserves, is hard to
see unless you turn off the States layer. Instead of having to do that, you can make the
state layer partially transparent.
 Double click on states.shp to open the Layers Properties dialog box. Click on the Display
tab, and set the Transparent value to 75%. Click OK.
? Which coast of the US are most of the NERR sites located on?
You can make raster,
TIN, and feature layers
transparent in scenes
and maps. For example,
you can use transparent
layers to:
•Visualize data that is
scattered above and
below a reference plane
•Compare two surfaces
•Show terrain and
subsurface features at
the same time
___________________________________________________________
You will select and work with those sites within the New England states.
 Turn on ne_states, right click on it, and select Zoom To Layer.
You can also use the
Adjust Transparency
tool on the Effects
toolbar in ArcMap to set
the transparency for a
layer.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
1. Select New England NERRs by Location (cont’d)
 On the menu bar,
click Selection > Select by Location.
 Choose to select features from
 The NERRs layer
 That intersect
 The features in the ne_states layer
 Click Apply and Close
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
Web Sites
1. Select New England NERRs by Location (cont’d.)
For more information on
the National Estuarine
Research Reserves
System visit
http://www.ocrm.nos.n
oaa.gov/nerr/
As you can see, there are four National Estuarine Research Reserve sites within New
England. One each in Maine, New Hampshire, Massachusetts, and Rhode Island. They
are the Wells NERR, Great Bay NERR, Waquoit NERR, and Naraganset NERR
respectively.
 To create a separate shapefile of just these selected sites, right-click on NERRs and
choose Data > Export Data. Export the selected features using the same coordinate
system as the layer’s source data, and save it in your student directory under /ex6 as
new_nerrs.shp.
 Click Yes to add the data to your map.
 Right-click on NERRs, and choose Selection > Clear Selected Features. Turn off NERRs.
 Again, your new NERRs layer may be hard to see until you change the color. Double click
on the symbol box of new_nerrs and change the fill color to a bright red. Change the
outline color to red as well. Click OK.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
Did You Know?
2. Select Watersheds by Location
Watersheds
Now that you have the New England NERRs, you want to know which watersheds they
are part of.
 Turn on the ne_watersheds shapefile.
 Choose Selection > Select by Location. Set the parameters so that you are selecting
features from ne_watersheds that intersect with new_nerrs. Click Apply. Close the
dialog box when it is finished.
 Zoom in on the selected watersheds. In the Table of Contents, right-click on
ne_watersheds and choose Selection > Zoom to Selected Features.
 Right-click on ne_watersheds and export the data as a new shapefile to your student
directory. Name it nerr_watersheds. As before, export just the selected features and use
the source data layer’s coordinate system.
 Add the new data layer to the map.
“That area of land, a
bounded hydrologic
system, within which all
living things are
inextricably linked by
their common water
course and where, as
humans settled, simple
logic demanded that
they become part of a
community."
John Wesley Powell,
geographer
Remember - no matter
where you are, you're in
a watershed!
 Right click on ne_watersheds, Selection > Clear Selected Features. Turn off
ne_watersheds.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 1: Formatting Data for Analysis
3. Select Counties by Location
You will now select the counties that contain these watersheds, and therefore influence
the NERR sites.
 Turn on ne_counties.
It is difficult to see the county borders underneath the watershed polygons. Making
nerr_watersheds partially transparent will allow you to view both layers and all their
boundaries. Also, if your new shapefiles are assigned colors which are not easy to
distinguish from the others, always feel free to change the symbol color.
 Open the Layer Properties for nerr_watersheds. Click the Display tab and make the
layer 40% transparent.
9
Did You Know?
Spatial Bookmarks
A spatial bookmark
identifies a particular
geographic location that
you want to save and
refer to later.
Bookmarks are easy to
create. Once you have
your data view set to a
particular area, simply
go to
View > Bookmarks >
Create
 From the menu bar, click on View > Bookmarks. Select RI_watershed.
 Right-click on ne_counties, and choose Label Features.
You are looking at the area surrounding the Narragansett NERR in Rhode Island. As you
can see, the watershed for this area overlaps several counties. Some more than others.
For example, Worcester and Plymouth counties each have substantial areas within the
watershed zone. Middlesex County, on the other hand, overlaps the watershed by just a
small piece. You want to select only those counties with at least a moderate impact on the
watershed area.
As you pan and zoom
around your map, you
can easily return to the
study area by accessing
the bookmark.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
3. Select Counties by Location (cont’d)
 Navigate to Select by Location.
 In the Select by Location dialog box, choose to select features from the ne_counties
layer, that have their center in features from the nerr_watersheds layer. Click Apply.
Move the dialog box to the side, and see that many of the influencing counties
surrounding the NERR have been selected, but not all of them. You will now add to your
selection those counties which do not have their center within the watershed region, but
are still considered significantly within the watershed.
 For your next selection in the Select by Location dialog box, choose to add to the currently
selected features in, and keep ne_counties checked. Choose those features that are
within a distance of features in nerr_watersheds.
 You will notice that the option to enter a distance buffer becomes available. Enter –2, and
change the units to miles. This will select those counties which overlap the watershed by
at least 2 miles. Click Apply.
 Close the dialog box when the selection process is complete.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
3. Select Counties by Location (cont’d)
 Right-click on ne _counties and turn off the labels. Then choose Selection > Zoom to
Selected Features.
 Export the selected features to create a new shapefile. Name this layer
watershed_counties.shp and save it to your student directory. Choose Yes to add this
data to your map.
 Clear the selected features from ne_counties, and turn the layer off.
 Rearrange your Table of Contents so that the top three layers are new_nerrs,
nerr_watersheds, and watershed_counties in that order from top to bottom. To move a
layer, simply highlight it and drag it up or down in the Table of Contents.
You now have those counties which influence the New England NERR sites selected and
in a separate shapefile to work with for the rest of this exercise.
? Why was it important to select counties that overlapped with the watershed
regions, instead of just those that intersected with the boundaries of the NERRs?
(answer in your lab report)
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
Did You Know?
3. Select Counties by Location (cont’d)
The TIGER/Line files
are a digital database of
geographic features,
such as roads,
railroads, rivers, lakes,
political boundaries,
census statistical
boundaries, etc.
covering the entire
United States.
 To see a comparison, add
nerr_counties.shp to your map. The area around
Narragansett NERR is a good example of how many counties would have been missed
without considering the watershed coverage.
 Remove nerr_counties from the Table of Contents.
4. Find Census TIGER Data
Census data can be very useful in evaluating and understanding the geographic patterns
of human activity. These data can also help us visualize the proximity of the activities to
environmental areas. Understanding the types and extent of certain activities can aid
coastal managers in protecting coastal areas and resources.
 Open the Attribute Table for watershed_counties, and examine the various data fields.
Notice that this table contains 1990 population data for each of the selected counties.
More up to date population figures are available, as well as a variety of other demographic
data. You will find and use Census TIGER data for this additional information.
The TIGER/Line files
are downloaded in
compressed shapefile
format for a selected
county or data layer.
TIGER® stands for
Topologically Integrated
Geographic Encoding
and Referencing
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 1: Formatting Data for Analysis
4. Find Census TIGER Data (cont.)
 Open Internet Explorer and go to www.google.com. Search for “2000 census tiger data”
 The first entry of your search results should be Geography Network. Click on this entry
to go to the Geography Network site.
 This is a site, operated by ESRI, where you can easily download free Census Tiger data.
Click on the link to Download Data.
 The next page allows you to choose Census data by state. Select any state of interest to
you, either by clicking on the map or selecting the state name from the drop down menu.
 The following page is where you select the data you wish to download by county or data
layer. Take a moment to explore this page, particularly the various options under the
Select by Layer menu to become more familiar with the types of data available. In your
lab report, briefly describe some of the files that you have downloaded and opened
due to your own interest. Include the readme file from one of the layers in your lab
report.
 In the interest of time, the necessary data for all the New England counties has been
downloaded and put into a single table for you. It is important however, for you to know
where this data came from, in the case that you need to use Census data in the future.
13
Did You Know?
The Geography
Network is an online
resource for finding and
sharing geographic
content, including maps
and data, from many of
the world's leading
providers.
The Geography
Network can also be
accessed directly
through ArcMap!
File > Add Data from
Internet > Geography
Network
FYI
For this exercise we are
using Census County
Demographics (SF1).
 Close the Geography Network window.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 1: Formatting Data for Analysis
5. Join Table to Shapefile
In the next exercise you will calculate the population change between 1990 and 2000. In
order to do that, you will join a table of 2000 demographic statistics, including population,
to your watershed_counties layer.
 If necessary, open the attribute table for the watershed_counties layer.
 Use
to add the table called ne_dem_2000.dbf. from the data folder. This table is the
previously mentioned aggregate file of Census Tiger data, and contains the demographic
data for all the New England counties. Right click on the title and open the table.
 Arrange the two tables so you can view the field headings of both at the same time.
In order to join two tables they must share a common field, known as a common key. Look
at the column titled “FIPS” in the watershed_counties table. Compare that to the “STFID”
column in the ne_dem_2000 table. They have different headings, but both contain unique
identifying numbers referring to the same thing. (The first two numbers are the state code,
and the last three numbers are the county code). You will use these fields as the common
key for the tables.
Remember, watershed_counties is a subset of counties you created from ne_counties so
it does not contain records for every county in New England, as ne-dem_2000 does. You
are only interested in the information from ne_dem_2000 that corresponds to the counties
in your watershed layer.
 Close the Attribute Tables.
14
Did You Know?
If you have information
stored in a table, such
as a dBASE, INFO, or
geodatabase table, you
can associate it with
your geographic
features and display the
data on your map by
one of two methods:
Joining tables appends the attributes
from one table onto the
other based on a field
common to both tables.
Relating tables defines a relationship
between two tables—
also based on a
common field—but
doesn't append the
attributes of one to the
other. Instead, you can
access the related data
when necessary.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
5. Join Table to Shapefile (cont’d.)
 Since you will be joining data to
watershed_counties, begin by opening its
Layer Properties. In the Layer Properties box,
click on the Joins & Relates tab. Under
Joins, click the Add button.
 Make sure the first pull-down menu is set to
Join attributes from a table.
 Choose FIPS as the field to base the join on.
 Choose ne_dem_2000 as the table being
joined.
 Choose STFID as the other field to base the
join on.
 Click OK.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 1: Formatting Data for Analysis
5. Join Table to Shapefile (cont’d)
 In the Layer Properties box, click on the Fields tab. Examine the new fields that have
been added. You will have to widen the Name field to view the field titles in this table.
Notice that the title now includes the name of the table it originated from. This is
particularly helpful when you have commonly named fields.
 Close Layer Properties and any open tables.
 Save your map document.
In Part 1 you selected NERRs in New England, selected watersheds that intersected with
the New England NERRS, and selected counties that were significantly within those
watersheds. You did this to find the counties whose populations and activities have an
influence on the NERR sites. Once you had these counties, you were able to join Census
TIGER data to your county shapefile.
In Part 2 you will use this and other demographic data to look at and map various
population and environmental parameters.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Discussion: Applying These Skills Elsewhere
Can you think of other scenarios where political vs. natural boundaries
could be an issue? (answer in your lab report)
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
Background
Goal
Now that you have determined the areas influencing the
New England NERR sites, your interests will focus on the
population changes and demographics of these areas.
After looking for areas of especially high population
change, you will concentrate on Barnstable County,
Massachusetts, the location of the Waquoit NERR. It will
be up to you to determine which of the county
demographic data is most important to consider for
coastal management purposes, and the best way to
display the information you have.
To use census and other tabular data to calculate and
represent population changes. The student will also have
the skills to display demographic information in an
appropriate and meaningful way.
Objectives
1. Perform table calculations
2. Use and understand different legend classifications
3. Create a map layout using multiple data frames
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
Tools to Use
Summary of Process Steps
Data
1. Add and Calculate a New Field – show the population
change between 1990 and 2000
2. Display Population Data – look at several population
parameters including total population, population
density, and population change
3. Join Tables – join demographic data to a county
shapefile
4. Use Different Classification Methods – use and
understand the various classification schemes available
in ArcMap
5. Layer Symbology – learn more about the tools
available to effectively display your data
6. Choose Four Demographic Parameters to Map –
select and customize maps for four parameters of
interest to coastal managers
7. Create a Map From a Template – a quick look at some
of the templates available in ArcMap
8. Create a Map Layout with Multiple Data Frames –
use the Layout View to customize your map
9. Tips For Customizing Your Map Layout – tips for
adding map features, customizing legends and data
frames
New_England.mxd
ArcMap document
nerr_watersheds.shp
Polygon shapefile of
watersheds adjacent to
NERRs
watershed_counties.shp
Polygon shapefile of
watershed influencing
counties
trt25001.shp
Polygon shapefile of
Barnstable census tracts
t9025001.dbf
DBF table of Barnstable
demographics
York.mxd
ArcMap document
Field Calculator
Use this tool to perform
mathematical
calculations to set a
field value for a single
record or all records.
Join Data
Use this function to
append additional data
to a layer’s attribute
table
Change Layout
Lets you change the
layout of your map by
choosing a different
template
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
1. Add and Calculate a New Field

If necessary, start ArcMap and open the NewEngland.mxd map document you saved
from the previous exercise. Open the Attribute Table for watershed_counties.shp.
You will now create a new field to show the population change from 1990 to 2000.

In the Attribute Table click on Options > Add Field. Name the new field pop_chng and
change the Type to Long Integer. Click OK.
The new field will be inserted as the last column of the original data set, in this case the
last column with watershed_counties in the title.

Right-click on the new field header and choose Calculate Values.

A message will pop up warning you that you have not started an editing session. Click
No to exit the message, and begin an editing session. To do this, Click Editor on the
Editor toolbar and choose Start Editing. In the Start Editing dialog box, highlight your
source folder (ex6_coast in your directory) and make sure watershed_counties is listed
as being available for editing. Click OK.

Return to Calculate Values to bring up the Field Calculator.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 2: Analysis and Display of Demographic Data
1. Add and Calculate New Field (cont’d.)

In the Field Calculator set the expression to read
[ne_dem_2000.POP2000] – [watershed_counties.POP1990]
Click OK.

After the calculations have completed, take a moment to look at the numbers. It may be
easier to put them in order. To do so, right-click on the field heading and choose Sort
Descending.
?
Which county has experienced the greatest population change? Does any one
state appear to be changing more than the others? Have any county populations
decreased? Which one(s)? (answer in your lab report)

Close the Attribute Table when you are finished.
21
FYI
Mouse Over Tip
Sometimes layer titles
are longer than the
spaces provided for
them (as in the Field
Calculator) and are hard
to read. Rather than
having to scroll over to
read the full title, hold
your cursor over the
layer name for a second
and the name will
appear in its entirety!
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
2. Display Population Data
Now that you have joined the demographic data to the watershed_counties layer, you
can use the new attributes to symbolize the layer.

Zoom to the extent of watershed_counties and turn off the nerr_watersheds layer.

Double click on watershed_counties and select the Symbology tab if necessary.

Choose to Show Quantities, and Graduated colors.

For Value, select ne_dem_2000.POP2000. Drag the Properties box to the side so you
can view your map. Click Apply.
This is showing the population, or number of people, in the selected New England
counties. While this is useful information, it may not be the best way to show how
populated each of the counties are. Now you will look at population density, or the
population per square mile. This can be done two ways. You could create a new field in
the attribute table and calculate the population density (pop2000/area), as you did to find
the population change. You can also normalize, or divide one attribute by another, and
get the same result. Normalization can be done in the Symbology section of the Layer
Properties box.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
2. Display Population Data (cont’d)

With Value still set to ne_dem_2000.POP2000, select watershed_counties.AREA for
Normalization. Click Apply. Notice how the classification of the counties changes on the
map.

Set Normalization back to NONE. Choose the field you created,
watershed_counties.pop_chng, as the Value. Click Apply. This shows how much the
population changed between 1990 and 2000.
?
You have seen how displaying population data differently affects the map. When
might you be interested in each of these three parameters? Total population;
population density; population change? (answer in your lab report)
For the remainder of this exercise you will focus on a county that is experiencing a high
degree of population change. As you can see on your map, the area around Waquoit
NERR on Cape Cod, Massachusetts has undergone some of the highest levels of
population change. We will look more closely at Barnstable County.

Close Layer Properties.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 2: Analysis and Display of Demographic Data
3. Join Tables

You will now add two new items specific to Barnstable county. One is a shapefile of
Barnstable county divided up by census tracts. The other is a table with the associated
demographic data by census tracts. These data are Census TIGER files and were
downloaded from the Geography Network Web site.

Add trt25001.shp and t9025001.dbf from the data folder in your student directory. A
warning box will pop up telling you that these items are in a different projection than your
current map projection. Click OK. For the best possible alignment and accuracy you
would want to actually change the coordinate system of the new layers, but for our
simple viewing purposes ArcMap’s “on the fly” projection change is sufficient.

In the Table of Contents, change the layer name of trt25001.shp to Barnstable census
tracts. Turn off all layers except Barnstable census tracts. Zoom to that layer.

Open the tables for the Barnstable layer and t9025001.dbf. Scroll all the way to the right
in t9025001. The common field for these tables is titled KEY. This is the field you will use
to join the two tables. Close both tables.

Join the table t9025001 to the Barnstable census tracts layer. (Remember, this is done
through the Layer Properties box of the Barnstable layer). Make sure that you
understand the process.
24
Did You Know?
ArcMap supports
project on the fly,
meaning that you can
make a map in one
projection(referred to as
a coordinate system)
and have your data
stored in any number of
projections.
To enable a feature
layer to be projected on
the fly, ArcMap needs to
know the source
coordinate system (for
the layer) and the target
coordinate system (for
the Map display).
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
4. Use Different Classification Methods

Open the Layer Properties for the Barnstable layer and click on the Fields tab. Scroll
through the list of fields to see what new information is available to you. There are
significantly more data fields at the census tract level than there were at the county
level.

Click on the Symbology tab. Under Show, select Quantities: Graduated colors. For
Value, select t9025001.PERSONS. Move the Properties box to one side so you can
view your map. Click Apply.
Notice in the Classification section of the Properties box, where it says Natural Breaks
(Jenks). This is the default method of classification in ArcMap. This method uses natural
groupings or patterns in the data to define classes and shows clusters or concentrations
of values.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 2: Analysis and Display of Demographic Data
4. Use Different Classification Methods (cont’d)
Also notice that a border of water surrounding Cape Cod is included in this layer and is
being classified. Look at the classification ranges. The first one goes from 0 – 1100.
Since we aren’t interested in the water area, we can assume it has zero “persons” and
exclude it from our data display.

Did You Know?
The most common
classification methods
are:
Natural Breaks –
identifies breakpoints
between values
In the Properties box, click Classify. Click Exclusion.

Under the Query tab, set the expression to read "t9025001.PERSONS" = 0

Under the Legend tab, make sure the box for “show symbol for excluded data” is
unchecked. Click OK. Click OK in the Classification box, and then Apply in the
Properties box.
Not only does the map look better without the surrounding water area, those 0 values
will no longer be incorporated into classification schemes, which could potentially skew
the results.

26
Return to the Classification box by clicking on Classify. Examine the graphical display.
The blue lines on the graph show where the data are broken into different classes. Put
your cursor over one of the lines. The cursor turns into a side-to-side arrow, allowing you
to click on and move the break line to a new value. Notice that as soon as you do this,
the method type automatically changes to Manual. The Break Values listed to the right
also reflect the changes being made.
Quantile – each class
contains the same
number of features
Equal Interval – divides
values into equal ranges
Standard Deviation –
shows distributions
above and below the
mean
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
4. Use Different Classification Methods (cont’d)

Change the Classification Method type to Equal Interval. This classification scheme
divides the range of attribute values into equal-sized subranges. For example, values
that ranged from 0-50 and had 5 classes, would be divided as 0-10,11-20, 21-30, etc.

Click OK and Apply to see the changes on the map. What do you think of the changes?
This map doesn’t show as much variety between counties. Look again at the graphic in
the Classification box. Notice that most of the data fall within 2 classes, so this
classification type would probably not be the best choice for this data set.
What types of data may be better suited for equal interval classification? (answer
in lab report)
?

This time, change the Classification Method to Quantile. In a quantile classification,
each class contains an equal number of features. Click OK and Apply to see the
changes on the map.
For any of these classification methods, you can also change the number of classes.
Experiment with this for a moment.
As you have seen, your map will look very different depending on the classification
method and number of classes you choose to use. An important aspect of displaying
any data is finding the combination best suited for your data and what you want it to
show.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
5. Layer Symbology
In addition to changing the way your data is classified, you have many other options
available as to how to display your data.

Under Show: Quantities, change from Graduated color to Dot density. Highlight
t9025001.PERSONS in the Field Selection box, and click on the arrow to move it into
the box on the right. Change the Dot Value to 500, and click Apply. Each dot represents
500 people.

This time, change the Symbology to Proportional symbols. Select
t9025001.PERSONS for the Field Value. This time you get a warning about this field
having some zero values and asking you to exclude them. Using the Exclude button,
exclude the data where persons equal zero, just as you did previously. Click Apply. In
this case, the symbol size represents total population values.

To look at population density, normalize t9025001.PERSONS to the size of the counties.
(In this case, t9025001:LAND_KM). Areas of high population density are now much
easier to distinguish.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 2: Analysis and Display of Demographic Data
5. Layer Symbology (cont’d)

Under Show, click on Charts and select Pie. This type of symbology makes it easy to
compare related fields. As an example, we’ll look at how people in this area get to work.

About halfway down the Field Selection box, highlight and move to the right the fields
DRVALONE, CARPOOL, and PUBTRANS. Click the Size button, and change to size to
22 pts. Click OK and Apply.

Let’s say you are particularly interested in seeing the percentage of commuters who use
public transportation. The color scheme is randomly assigned for the pie chart, but you
can change it. Double click on the symbol next to PUBTRANS in the Layer Properties
box, and change it to bright yellow. Click Apply.

Finally, change the classification back to showing population density in Graduated colors
using Natural breaks.

Close Layer Properties.
29
Did You Know?
Styles
An organized collection
of symbols and map
elements
ArcMap starts with two
default symbol styles:
ESRI and a Windowgenerated symbol set.
Many other industry
specific (civic, weather,
evnironmental, real
estate, etc) styles can
be accessed at:
Tools > Styles > Style
Manager.
There are over 12,000
symbols available in
ArcMap!
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
6. Choose Four Demographic Parameters to Map
Read this section so that you understand your objective, and then move onto sections 7
and 8 for further instructions and tips on creating your map layout.
Choose four parameters that you think would be of interest to a coastal manager for the
area. They can be ones you have already worked with, or new ones. Look through the
attribute table and see what you can come up with. Try to incorporate some of the
different classification methods and symbology styles you have just learned about.
Choose between either Wells NERR in York, Maine or Waquoit NERR in Barnstable,
Mass. If you choose to work with York, Maine, you will find a York.mxd map document in
the data folder with the necessary files.
Feeling stuck? Start with something simple like population density, either as a graduated
color or proportional symbol. Or show housing units using dot density. How about a pie
or bar chart of residences that use public vs. private sewage systems? You could show
the ratio of housing units that are renter occupied versus owner occupied, rental rates by
graduated color, which counties have a majority of seasonal residents, or look for areas
with older homes – those built prior to 1970.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 2: Analysis and Display of Demographic Data
7. Create a Map From a Template
Before you begin your own layout, you will see how templates can be used to make
quick and easy maps.

If necessary zoom to the extent of the Barnstable layer.

Change to the Layout View by clicking on the

Go to File > Save as. Navigate to your student working directory, name your file Blank,
and change the file type to .mxt. You have just saved a blank template that you will be
using in the next exercise.

Click the Change Layout

In the Select Template box, click the General tab and highlight LetterLandscape.mxt.
Click Finish. Notice that the template includes a standard title area, north area, scale
bar and legend. You can click on any one of these and drag it to a more appropriate
place on your map layout.

Click the Change Layout button again. This time choose LandscapeClassic.mxt.
tab near the bottom of the map view.
31
FYI
Template saving tip
If you save a template
in the ArcMap
Templates folder
(\ArcGIS\arcexe82\bin\
Tempates), it will show
up in the list of
templates on the
General panel of the
New map document
dialog box.
button on the Layout Toolbar.
These are just a few of the many templates available to you. Explore them more
thoroughly on your own when you have time.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
8. Create a Map Layout With Multiple Data Frames
In this section of the exercise you will be creating one map layout comprised of four
separate maps. Each of the four maps will come from a different data frame in ArcMap.
So far you have been working with all your data in one data frame. You will need to
create three more data frames. The same data layers can be used in all the data
frames, but each can be customized to show something unique.

Click the Change Layout button and under the My Templates tab, select the blank.mxt
template you created in the previous section.

Under File > Page Setup, change the Page Orientation to Landscape.

In the Layout View, click on the data layout. Once it is highlighted, grab a corner and
reduce it to about ¼ the size of the page. Position this data frame in one quadrant of
the page.

Your default (and only) view at this point is named Layers. Rename it to Data Frame 1.
You can do this by clicking on the title in the Table of Contents, or by going through its
Properties box. Also in the Data Frame Properties box, click on the General Tab and
change the display units to “Miles”. The map units should be decimal degrees.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
8. Create a Map Layout With Multiple Data Frames (cont’d)

You will now create three more data frames. Click Insert > Data Frames. In the Layout
View resize it to be the same as Data Frame 1. Reposition it in another quadrant of the
page. In the Table of Contents rename the New Data Frame to Data Frame 2.

Repeat this process until you have four Data Frames.
When you are sizing and positioning your data frames, you may want to leave space at
the top of the page for a title and at the bottom for all the other important cartographic
elements that you need to include on your map (Remember the SIX cartographic
elements!).
In order to work with an individual
data frame, it must be active.
You can make a data frame active
by clicking on it in the Layout View
or right-click it and select Activate
in the Table of Contents.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
8. Create a Map Layout With Multiple Data Frames (cont’d)

If you haven’t done so already, rename your new data frames – Data Frame 2, 3, and 4.

In Data Frame 1 in the Table of Contents, right-click on Barnstable census tracts and
select Copy. Paste it into each of the other three Data Frames. (Right-click on each of
the Data Frames in the Table of Contents and click Paste Layer)
Now you are ready to begin customizing each data frame to display a different
parameter from the data available to you. You can switch back and forth between the
Data View and the Layout View. The Data View will show only the active data frame and
it may be easier to work with the individual data frames in this mode.
Feel free to copy and paste any other layers into your new data frames as needed. For
example, having new_nerrs would be useful to show where the Waquoit (or Wells)
NERR is in relation to the demographics within the county.
See the next page for suggestions on customizing your map. As you customize a data
frame, have fun, and be creative!

When you have finished, save your map document and prepare a copy (screen shot) of
your map for your lab report. Close ArcMap.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 2: Analysis and Display of Demographic Data
9. Tips For Customizing Your Map Layout
Since you are not using a template, you will need to add your own legend, north
arrow, and scale bar. This can be done using the Insert portion of the menu bar.
The Legend Wizard that comes up when you click Insert > Legend, offers a variety of
options for customizing your legend. It is relatively self explanatory and allows you to:
- choose which layers to include in your legend
- change background colors and border styles
- change symbol patch styles
You can also change layer titles. When you customize the symbology of each layer, an
additional title gets added to the layer describing the classification. For example, look at
the Barnstable census tract layer in any of the Data Frames. If you haven’t already
changed it, the sub-title should read t9025001.PERSONS/t9025001.LAND_KM. Not a
very clear title to have on your map legend! Highlight the sub-title and click it once to
change the name to something more appropriate, like Population Density. Changing it in
the Table of Contents will automatically update it in your layout, even if you’ve already
added the legend for that Data Frame.
To customize the look of the data frame itself, you can double click on the Data
Frame title in the Table of Contents or right-click > Properties on the data frame in the
Layout View. This brings up the Data Frame Properties box. Go to the Frame tab to
change the background colors and border styles of each data frame.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Discussion: Overview of Management Applications
1. Which parameters did you choose to include in your map?
2. What other data would you like to have analyzed, given more time?
(answer these questions in your lab report)
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 3: Using C-CAP Data to Determine Impervious Surfaces
Background
Goal
Land cover information can give you, a coastal resource
manager, insight into how the land in your area is being
utilized. This in turn can help determine the impact of
different coverage types on local habitats or water quality.
In this exercise you will find the amount of impervious
surface in two NERR watersheds and compare the
results. Impervious surfaces are of interest because they
are a main contributor to surface water runoff and its
effects, including water quality degradation, erosion,
flooding and sedimentation. You will use land classified as
Developed to determine imperviousness since
development results in more paved surfaces and less
area for water to drain into soils.
After completing the exercise, the student will better
understand C-CAP data and how they can be used in
coastal management.
Objectives
1. Become familiar with C-CAP data classifications
2. Use C-CAP data to determine the percentage of
impervious surface within watersheds
It should be noted that for Part 3 we are considering all
developed land to be impervious. While this will only give
us a very rough estimate, it is adequate for our
comparison purposes. You will be given the opportunity to
do more precise calculations in the Challenge Exercise.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 3: Using C-CAP Data to Determine Impervious Surfaces
Summary of Process Steps
1. Examine C-CAP data classifications – familiarize
yourself with the classification schemes used in C-CAP
data
2. Determine the percentage of impervious surface in
the Great Bay NERR watershed – use the Select by
Attribute function and table Statistics to calculate this
percentage
3. Determine the percentage of impervious surface in
the Narragensett Bay NERR watershed – repeat the
process for the Rhode Island NERR watershed
Data
CCAP.mxd
ArcMap document
ne_nerrs
Polygon shapefile of NERRs
in New England
nerr_watersheds
Polygon layer of watersheds
adjacent to NERRs
nh_nh19930612.img
C-CAP land cover image of
New Hampshire
ma_ma19970623.img
C-CAP land cover image of
Massachusetts
NHnerr_landcov
C-CAP land cover layer of
Great Bay NERR area
RInerr_landcov
C-CAP land cover layer of
Narragansett Bay NERR area
38
Tools to Use
Select By Attribute
Use this function to
select features based
on their attributes
Statistics
Use this function to get
statistics describing the
values in a table’s
numeric columns, such
as the sum, minimum,
mean, maximum, and
standard deviation of
those values.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 3: Using C-CAP Data to Determine Impervious Surfaces
Web Sites
1. Examine C-CAP Data Classifications
For more information on
the CCAP data, visit:
 Start ArcMap and open the CCAP.mxd map document.. You are looking at two full C-CAP
scenes covering much of the New England coastal area.
www.csc.noaa.gov/crs
/lca/ccap.html
 Turn on ne_nerrs and zoom to the Wells NERR (WEL) in Maine.
To download CCAP
data, visit:
www.csc.noaa.gov/crs
/lca/locate.html
Or
www.csc.noaa.gov/crs
/lca/locateftp.html
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
40
Part 3: Using C-CAP Data to Determine Impervious Surfaces
1. Examine C-CAP Data Classifications (cont’d)
 Turn off ne_nerrs and examine the land cover in the Wells NERR. Consult the C-CAP
legend in the Table of Contents.
? What type of land cover makes up most of the Wells NERR area?
? Notice the white lines running north-south in the area. What do they represent?
(answer in lab report)
 Zoom to the extent of ne_nerrs and turn the layer back on. Also turn on nerr_watersheds.
For the rest of the exercise you will be looking at land cover within the watersheds of Great
Bay and Narragansett Bay NERRs.
 Turn off nh_nh19930612.img and ma_ma19970623.img, and close their legends (by
clicking the minus sign next to their name).
 Turn on NHnerr_landcov and expand its legend.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
Part 3: Using C-CAP Data to Determine Impervious Surfaces
1. Examine C-CAP Data Classifications (cont’d)
 Turn off the watershed layer so that you can see the land cover grid. This layer shows just
the land cover within the Great Bay NERR watershed.
41
FYI
The land cover grids
were produced in
ArcView 3x using the
C-CAP Data Handler
Extension.
 Zoom to the NHnerr_landcov layer, and open its Attribute Table. The attribute table
contains records for each of the land classifications (Class_names) along with how many
pixels are assigned that classification (Count). Also notice the Level1 field which is a more
generalized set of land cover classifications. For example, Level1 classifies the three
forest land cover categories (Deciduous, Evergreen, and Mixed Forest) into one Forested
Land class.
2. Determine the Percentage of Impervious Surface in the Great Bay NERR
Watershed
You will now find the total area (represented by pixels) of the watershed, and the area
classified as Developed in order to calculate the percentage of impervious surface.
 In the Attribute table right-click on the Count field header, and go to Statistics. First, you
are interested in how many pixels make up the entire watershed scene. That is
represented by the Sum. Jot that number down. ____________ (Total pixels in NHnerr
watershed) Close the Statistics window.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 3: Using C-CAP Data to Determine Impervious Surfaces
FYI
2. Determine the Percentage of Impervious Surface in the Great Bay NERR
Watershed (cont’d)
You may have noticed
that the color for
selected items is the
same as symbol color
for …. In the C-CAP
data legend. There isn’t
much…. Present in
these land cover scenes
so it did not pose a
problem for
distinguishing the
selected items. If it had,
however, it is possible
to change the Selection
color for better contrast
with your layers.
 In the Attributes window, click Options > Select by Attributes.
 Create a new selection using the expression Level1 = ‘Developed Land’. Click Apply.
As you can see in the Attribute Table, this has selected those pixels designated as both
High and Low Density Developed.
 Close the Select by Attribute window, and move the Attribute Table so that you can see
the areas selected on the land cover grid.
 In the Attribute Table, right-click on Count and go to Statistics. This time it is only
considering the selected areas, so the Sum in this case are just those pixels classified as
Developed Land. Jot this number down: _________ (Developed Land pixels in Nhnerr
watershed) Close the Statistics window.
 To find the percentage of this watershed that has impervious surfaces divide the
Developed Land pixels by the Total pixels. (A calculator can be found by clicking on Start
at the bottom of your screen. Start > Programs > Accessories > Calculator)
______ % of the NHnerr watershed is impervious surface.
To Change the
Selection Color, click
Selection > Options and
choose a new Selection
Color
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
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Part 3: Using C-CAP Data to Determine Impervious Surfaces
3. Determine the Percentage of Impervious Surface in the Narragansett Bay
NERR Watershed and put this in your lab report.
 Follow the same procedures to determine the impervious surface percentage for the
Narragansett Bay watershed.
 Find the sum of all RInerr_landcov pixels
_________ (Total pixels in RInerr watershed)
 Select Developed Land, and find the sum
_________ (Developed Land pixels in RInerr watershed)
 Calculate the percentage of impervious surface
_________ % of the RInerr watershed is impervious
In Part 3 you worked with and became familiar with C-CAP data. You selected individual
land cover classes and used statistics about those classes to determine the percentage of
impervious surfaces in NERR watersheds.
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
44
Discussion: Overview of Management Applications
Challenge Exercise
1. Which watershed has more impervious surface?
Calculate more precise
estimates for
impervious surfaces.
2. What implications might this have on the NERR and the water quality
of the bay?
3. What else could you find out about the watershed region using CCAP data?
Consider High Intensity
Developed areas to be
90% impervious, and
Low Intensity
Developed areas to be
65% impervious.
answer in lab report
Don’t forget the Challenge Exercise!!
Does it drastically
change your results?
Answer in lab report
GEO 265 - GIS Practicuum
Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves
45
Congratulations!
You have completed Exercise 6!
Let’s quickly review what you did and what you learned –
You began by selecting NERRs in New England, and then finding the watersheds and counties
that influence those NERRs. By doing this you learned how to select features based on where
they are in relation to features in other layers.
Once you had the counties that made up these influential areas, you found and incorporated the
corresponding Census TIGER data. In the process, you learned not only how to find appropriate
Census data, but how to join tabular data to your existing shapefiles.
From there, you calculated the 1990-2000 population change for your counties and used a variety
of classification methods to display population information. This taught you how to create and
calculate new data fields, as well as getting you familiar with what classification types work best
with different data.
You then concentrated on one county (Barnstable, MA) and brought in its census
tract and demographic data. You used this data to create a map layout using
multiple data frames. Each data frame represented an environmental parameter
that you deemed important to coastal managers. Again, you gained experience
joining tables and using various classifications and symbology.
Finally, you learned about C-CAP data. You became familiar with the C-CAP
classification scheme, how to select individual land cover classes, and how to
use the attribute table statistics.
Most importantly, you learned how all of these skills can and are used in the
application of coastal management!
GEO 265 - GIS Practicuum