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.

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Transcript 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.

Introduction Part 1

Exercise 6 - ArcView 8 Population Demographics Adjacent to National Estuarine Research Reserves

Overview and the Coastal Context Formatting Data for Analysis Discussion Part 2 Discussion Applying These Skills Elsewhere Analysis and Display of Demographic Data 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

Courtesy of

More Impervious Surface Calculations

Written by OSU Marine Resources Mgmt. student Danielle Pattison

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

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

Part 1: Formatting Data for Analysis

Background

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.

Goal

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 3

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 1: Formatting Data for Analysis

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

Tools to Use Data

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 4

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 1: Formatting Data for Analysis

Did You Know?

1. Select New England NERRs by Location

 To begin, start map, navigate to the ex6_coast data directory in your student working directory and select the

ArcMap New_England

mxd

. When prompted, select to start the program with an existing 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

Transparency

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 ?

Which coast of the US are most of the NERR sites located on?

___________________________________________________________

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

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

Part 1: Formatting Data for Analysis

1. Select New England NERRs by Location (cont’d.)

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

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

Web Sites

For more information on the National Estuarine Research Reserves System visit

http://www.ocrm.nos.n

oaa.gov/nerr/

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 1: Formatting Data for Analysis

Did You Know?

2. Select Watersheds by Location

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.

 Right click on

ne_watersheds

, Selection > Clear Selected Features. Turn off

ne_watersheds

Watersheds

“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! 8

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 1: Formatting Data for Analysis

Did You Know?

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

Spatial Bookmarks

A spatial bookmark identifies a particular geographic location that you want to save and refer to later. 

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

layer

40%

transparent. tab and make the 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

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

Part 1: Formatting Data for Analysis

3. Select Counties by Location (cont’d)

 Right-click on

ne _counties

Selected Features. and turn off the labels. Then choose Selection > Zoom to  Export the selected features to create a new shapefile. Name this layer

watershed_counties.shp

data to your map.

and save it to your student directory. Choose

Yes

to add this  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) 11

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 1: Formatting Data for Analysis

Did You Know?

3. Select Counties by Location (cont’d)

 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.

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.

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.

The TIGER/Line files are downloaded in compressed shapefile format for a selected county or data layer.

 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.

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.)

Did You Know?

13  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.

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.

  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.

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. 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:   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.

Joining tables

appends the attributes from one table onto the other based on a field common to both tables.

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.

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.

 Close the Attribute Tables.

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 (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

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

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

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 18

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 2

: Analysis and Display of Demographic Data Summary of Process Steps

1. Add and Calculate a New Field –

change between 1990 and 2000 show the population

2. Display Population Data –

look at several population parameters including total population, population density, and population change

3. Join Tables –

shapefile join demographic data to a county

4. Use Different Classification Methods

understand the various classification schemes available in ArcMap

–

use and

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

Data

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 19

Tools to Use

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

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

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

 Return to Calculate Values to bring up the Field Calculator. 20

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

 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) 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!  Close the Attribute Table when you are finished.

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

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

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

Did You Know?



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

. 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

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.

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

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 level.

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  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 Did You Know?

4. Use Different Classification Methods (cont’d)

The most common classification methods are:

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 exclude it from our data display.

– 1100. Since we aren’t interested in the water area, we can assume it has zero “persons” and

 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

. Click

in the Classification box, and then

Apply

in the Properties box.

Natural Breaks

identifies breakpoints between values

Quantile

– – each class contains the same number of features

Equal Interval

– divides values into equal ranges

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.

 Return to the Classification box by clicking on the method type automatically changes to

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,

Manual

. The Break Values listed to the right also reflect the changes being made.

Standard Deviation

– shows distributions above and below the mean

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)

 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

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

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

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. 28

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 2: Analysis and Display of Demographic Data Did You Know?

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

pts. Click

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.

Styles

An organized collection of symbols and map elements ArcMap starts with two default symbol styles: ESRI and a Window generated symbol set. Many other industry specific (civic, weather, evnironmental, real estate, etc) styles can be accessed at: Tools > Styles > Style Manager.  Close Layer Properties. There are over 12,000 symbols available in ArcMap!

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

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 tab near the bottom of the map view.  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

button on the Layout Toolbar.

 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

These are just a few of the many templates available to you. Explore them more thoroughly on your own when you have time.

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.

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

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

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

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. 34

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

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.

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. 35

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

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

Part 3: Using C-CAP Data to Determine Impervious Surfaces Background

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.

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

Goal

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 37

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 3: Using C-CAP Data to Determine Impervious Surfaces Data 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

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

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. 38

GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

Part 3: Using C-CAP Data to Determine Impervious Surfaces Web Sites

1. Examine C-CAP Data Classifications

 Turn on

ne_nerrs

and zoom to the Wells NERR (WEL) in Maine.

For more information on the CCAP data, visit:  Start ArcMap and open the

CCAP.mxd

map document.

scenes covering much of the New England coastal area. You are looking at two full C-CAP

www.csc.noaa.gov/crs /lca/ccap.html

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

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. 40

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)

FYI

 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.

The land cover grids were produced in ArcView 3x using the C-CAP Data Handler Extension. 41  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

Part 3: Using C-CAP Data to Determine Impervious Surfaces

2. Determine the Percentage of Impervious Surface in the Great Bay NERR Watershed (cont’d)

 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.

FYI

42 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.

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

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

Discussion: Overview of Management Applications

1. Which watershed has more impervious surface?

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 C CAP data?

answer in lab report

Don’t forget the Challenge Exercise!!

Challenge Exercise

Calculate more precise estimates for impervious surfaces.

Consider High Intensity Developed areas to be 90% impervious, and Low Intensity Developed areas to be 65% impervious. Does it drastically change your results?

Answer in lab report GEO 265 - GIS Practicuum

Ex. 6 - Population Demographics Adjacent to National Estuarine Research Reserves

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