Land Use Mapping Project

Due Date: November 3, 2009

Construct a level II Land Use/Land Cover map for the area contained on the aerial image you downloaded from Google Map for this class. This map must be finished as a professional report map would be finished. This includes a title block with location, scale and legend.

You must also submit a written description of the project and area. The description should include information on the location of your image, UTM or lat/long corner coordinates, type of photography, map scale, resolution of your map and accuracy comments. Accuracy comments should include, but not be limited to general remarks about the accuracy of the map compared to what is found in that region today. You also should include a final paragraph with your concluding thoughts about this project.

This project is worth 100 points (70 points for the map and 30 points for the paper). Five points per day will be subtracted from the total for late papers.

Step 1: Finding the aerial view of your hometown

A. Open Google Earth. If your computer does not have a copy of Google Earth on it, you can download it for free by going to http://earth.google.com.

Find an aerial view of your hometown entering the address or zip code of your community. Be patient! The program should "fly" to this location.

B. Next you need to ZOOM in on the area you wish to map. To do this, just click on the navigation tools in the upper right of your screen. Practice moving north, south east and west. Zoom in and out. Familiarize yourself with the tools available.

C. Make sure the image you select is oriented with NORTH at the top of your map. Also make sure that your image is perfectly 'vertical'.

D. Once you have the image you would like to use, you need to have it approved by Dr. Ludwig. The best plan is to bring up the image on your screen and let her look at it. If that is not possible, you can save and email a copy of the image to her for approval.

Step 2: Saving a copy (actually two copies) of your image.

A. Once your image is approved, you should save your image(file-->save--> save image). Before you do this you need to TURN OFF EVERYTHING (look at the menus under VIEW and make sure everything is unchecked.) You want to save a clean image with nothing on it. (no legend, no grid, no nothing!).

B. After you have saved this "clean" image, go to the top menu bar under view and click on grid and legend. A lat/long grid should appear over your image and a legend will be placed in the SW edge of the map. Again SAVE this image--but make sure you give it a different name (such as imageGRID). If you have not moved the navigation tools, you should have two perfectly aligned images.

C. Open Adobe Photoshop. Import your google image by going to File-->Open and navigating to the location where you saved your images. Open the image WITHOUT the grid. This will become your "background" for your project.

D. Add a LAYER to your image by clicking the "add layer" icon on the layer window. If you can't find the layer window hit F7 and it should appear. Name this layer GRID.

E. Click on the layer called GRID. Basically just click on it in the layer box to make sure it is selected.
Go to File--> PLACE. Then navigate to the location where you saved the imageGRID file. Select it. This will place the second image on the layer called grid. If there is a big white X on the image, just click on it and the X should disappear. You now should have both the clean image and the image with the grid put into photoshop.

 

Step 3: Saving your file in the correct format

1. Launch Adobe Photoshop

2. Open the image by going to FILE > OPEN.  Navigate to your downloaded image.

3. Change the image to RGB by going to IMAGE > MODE > RGB Color.

4. SAVE by going to FILE > SAVE. When the box with the file on it opens, change the name to something you can remember and switch it to Photoshop format (see fig. 2). Save to your workspace folderand your USB storage device.


fig. 2 The Save pop-up dialog box (with the "Photoshop"file format circled).

Note: Because of the work involved in this project. I RECOMMEND you have at least TWO backup copies of your project. Keep one on a USB KEY and the other in the folder on the course server. At least one person in this class is going to complete this project only to discover that their file is gone or corrupted. You do not want that person to be YOU!!!! So.......heed these words.

 

 

Step 4: Learning to use the Toolbar

The major tools you will use for this project are identified in the graphic below. Try experimenting with them on a COPY of your image before you actually begin working.

 

Step 5: Using Layers

Layers are an important part of Photoshop. Basically they are similar to a transparent overlay that is placed over the top of the image. You can paint, draw lines, erase--basically anything you want on the layer. the beauty of using layers is if you make a mistake, just toss the layer away-- you haven't ruined the complete image.

The graphic below (fig. 4) shows the layers window. Selecting WINDOW and clicking on LAYERS in the menu will bring up this box. Typically this box will be open all the time.


fig. 4 - Layers floating palette with several sample layers

 

Step 6: Creating a new layer for your land use areas

First, enlarge your image to 100% size by holding down the  Control Key and hitting the + key.  Holding down the control key and hitting the - key will make your image smaller.  You should always be sure to work on your image at 100% size.  Some times you may want to zoom it a bit larger to help you determine land use patterns.  Try zooming (enlarging) your image so that it gets very blocky and pixelated.  These squares are individual pixels.  Unzoom back to 100%.

Once you are ready to define and work on outlining land use areas, create a new layer (by clicking on the "New Layer" icon in the Layers floating palette -- see fig. 4 above). To keep things easier, you should give names to your layers, and these names should be descriptive (see fig. 4 for name examples).To do so, right-click (or hold down the option key and click) on the layer you wish to rename and type in a new name.

I recommend you outline all land use polygons on one layer. Why? It makes it much easier to paint the individual land use types. After you have all land use areas outlined, simply duplicate the polygon layer so that one layer represents each Level I land use type. Then fill (using the paint bucket) only those polygons associated with that specific land type.

 

Step 7: Making your Polygon layer to outline land use areas

Make sure that the land use polygon layer you are going to work on is ACTIVE (it should be darker than the rest of the layers). Then, select the Pencil tool on the toolbar. Set the line width to to mark off your land use area to either 2 or 3 (on the Options Bar--just below the Menu).  Some students find it easier to use red or another visible color for the polygon lines.  I think it is easiest to just use black as a basic color for outlining the polygons, but it is your choice. Begin to outline each land use area as shown in fig. 5 below.  Hint:  You can easily draw a straight line with the pencil tool by clicking once where you want to start the line, then hold down the shift key and click where you want the line to end.


fig. 5 - Using the Pencil tool to draw
an outline of the land use area

Step 8: Coloring your land use area

Once you have all your land use areas outlined, you need to create a duplicate of that layer by right clicking (or option-click) on the layer name in the floating layer palette. Select Duplicate Layer and rename that layer using one of the Level I land use categories (ie Urban, Forest, etc.)

Select the color for "painting" by clicking on the eye dropper in the toolbar. Make sure the color palette is open (WINDOW-->SHOW COLOR-click on swatches) and click the eye dropper on the color you wish to use. You will notice that this color now is shown in the foreground color box on the toolbar.

Click on the Paint Bucket tool in the toolbox. Look for OPACITY on the Option Bar. Set it so you can still see the aerial photo. Typically 50-75% opacity works well--but it is dependent upon your individual photo.

Move your cursor over the area you wish to fill with paint and click.

Note: if the "paint" spills over and outside the area you wanted to fill, do an "undo" (EDIT -> UNDO FILL), and go back to your polygon outline. There must be NO GAP in your outline in order to contain the "paint" from your Paint Bucket tool. If a gap exists (even one tiny pixel) your paint will spill all over the image, covering it completely! If this happens, it isn't a big deal--just edit-undo... and use the pencil tool to close all "holes".


Fig. 6 - Using the Paint Bucket tool to fill
the outline of the land use area

 

Step 9: Numbering your land use area

For future reference, you need to number each area. To do so Photoshop automatically will create a new layer where you will put all the numbers. Activate the Text tool from the Toolbox and click over the area you wish to number. Adjust the font and the settings to your liking on the option bar - type in the number, and click "OK" when done. Note: Photoshop will create a new layer for each land use type. Some students have actually run out of layers (I think photoshop allows about 100 individual layers). You can MERGE several layers together to form one layer....and you might want to think about doing this for each level I land use type.

 

BEWARE - once you merge layers together, they can no longer be edited!!!!! Do this step carefully. I strongly recommend you make a backup copy before merging layers.

  1. Make sure only the layers you want to merge are visible (all should have eye icons on the Layers palette) and HIDE any layers you don't want to merge. They don't have to be consecutive. Hid the Background if you don't want to merge layers into it.
  2. Activate any one of the layers to be merged. BEWARE! If you merge an editable type layer or an adjustment layer, it will no longer be editable.
  3. Choose Layers-->Merge Visible from the top menu bar. This will put all the visible layers into ONE SINGLE LAYER.

 

fig. 8 - The land use area with a reference number
 
 



CLICK below to see a student examples from earlier classes.

Sample 1

Sample 2

Sample 3