All data is in Universal Transverse Mercator (UTM) Zone 6 projection, and WGS 84 datum.

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1 111 Mulford Hall, College of Natural Resources, UC Berkeley (510) EXPLORING MOOREA DATA WITH QUANTUM GIS In this exercise, you will be using an open-source FREE GIS software, called Quantum GIS, or QGIS. You can download QGIS at for free, and install it on both PCs and Macs. While QGIS contains less geoprocessing and spatial analysis tools than ArcGIS, it is an excellent program for exploring data and making maps, and best of all, it is FREE and EASY TO USE! In this exercise, you will be working with the Moorea datasets, some of which were downloaded from the Internet, and others which have been created from past research at Moorea. All data is in Universal Transverse Mercator (UTM) Zone 6 projection, and WGS 84 datum. ETM_satellite.tif - Landsat Enhanced Thematic Mapper (ETM) satellite image. 30-meter resolution. Source: Moorea_topo_bw.tif - Digital topographical map, in black & white. Source unknown. Moorea_topo_color.tif - Digital topographical map, in color. Source unknown. haapiti_photo.tif - Black & white aerial photograph of a portion (Haapiti area) of Moorea. Source unknown. papetoai_photo.tif - Black & white aerial photograph of a portion (Papetoai area) of Moorea. Source unknown. Airport.shp Airport location and runway. Source unknown. Channel_markers.shp Channel marker locations. Source unknown. hotel.shp Hotel location, points. Source unknown. hotel_bndy.shp Hotel property boundary. Source unknown. island_outline.shp Outline of the Island of Moorea. Source unknown. mooring2002.shp Locations of moorings, Source unknown. mpa1999.shp Marine Protection Areas, Source unknown. mpa2001.shp - Marine Protection Areas, Source unknown. mpa2002.shp - Marine Protection Areas, Source unknown. Reefs.shp Reef areas. Source unknown. Road.shp Main island road. Source unknown. towns.shp Town locations. Source unknown.

2 1. Start QGIS, by double clicking Quantum GIS (1.8) from your home screen. When the program opens, you can see that there is a Map area, Table of contents, Overview map area, and Toolbars. Click OK to close the QGIS tip. Toolbars Table of contents Map area 2. Find the Manage Layers toolbar, which looks like this: This is where you add data. There is a SEPARATE BUTTON for VECTOR, RASTER, GEODATABASE, and WEB MAPPING SERVICE data. You can also access each of these tools under the Layer menu. 3. Click on the Add a Raster Layer button: The Open dialog opens. Set Files of type to GeoTIFF. Navigate to C:\Workspace\Moorea\Moorea, and add the following layers: ETM_satellite.tif Haapti_photo.tif moorea_topo_bw.tif moorea_topo_color.tif papetoai_photo.tif

3 4. Experiment with different viewing options. Clicking the x next to the feature names in the table of contents will turn the layer on and off in the viewer. Moving the layer names in the table of contents will also change the order in which the layers are arranged in the viewer. 5. Click on the Add a Vector Layer button: Click the Browse button. Navigate to C:\Workspace\Moorea\Moorea, and add all the shapefiles layers that appear. Click Open twice to see the layers in your map. 6. Change the order (or turn off certain layers) until your map looks similar to the one below. 7. Change the symbology of your layers to appropriate symbols, by right-clicking and choosing Properties. For example, right-click on Road and choose Properties.

4 8. In the Layer Properties window for the Road layer, under the Style tab, choose from the saved styles at the bottom of the dialog window. * Note that if your window does not look like the one in the image to the right, you may need to click the New Symbology button in the top right corner. To fine tune your symbology selection, try adjusting the color and width. Click apply to see changes on you map. 9. Under the General tab, change the Display name to Main Moorea Road This is how you can change the display name in the Table of Contents. When you are finished setting the Layer Properties for the Road layer, click OK. 9. Open the Layer Properties for the island_outline layer. Under the Style tab, click the button to access more style options. Change the Fill Style to be No Brush, and the Border width to 1.5. Click OK.

5 10. Open the Layer Properties for the Reef layer, and under the Style tab, change the Transparency slider to be 50%. Explore the Map Navigation Toolbar Hover over each tool in the Map Navigation toolbar to see what they do: 1. Zooming & Panning Experiment with zooming in and out, using the zoom buttons. With the zoom in/out tools, you can either draw a box around the area you want to zoom in/out on, or you can click once. Use the pan tool to move the map around while staying at the same scale, or zoom level. There are many ways to move around your data use the tools that you like best! a. Click on Full Extent to zoom all the way out to all layers. b. Click once on a single layer to select it in the Layer List, and then click on Zoom to Layer: This will zoom your map to the extent of that layer only. 2. Identifying The identify tool can be a good way to browse the attribute information behind the geospatial data. Attributes are data that correspond to a spatial location, whether it is a point, line, or polygon shape. a. First click once on the towns layer to select it in the Layer List. b. Using the Identify tool, click on a town polygon. You can read the information about the feature that you clicked, in this case, the town s name. QGIS also has the

6 ability to automatically derive the area of selected polygon features, as seen in the results window. c. Explore other layers, such as the reefs and hotels, by identifying features. Be sure to select each layer in the Layer List to select it, before identifying it! 3. Measuring The measure tool is very good for performing fast and easy distance measurements. a. Click on the measure tool. A message might come up that looks like the one here. If it does, then you ll have to set the Projection. b. Go to the Settings menu, then to Project Properties. Under the Coordinate Reference System (CRS) tab, set the Projection to Projected Coordinate Systems > WGS 84 / UTM zone 6S. If you can t find it in the list, you can search for its ID by clicking EPSG ID and searching for c. Click once on the left side (west end) of the island and then on the right side (east end). Each left click will start a new segment. Right click to end the measurement. Try measuring some features of interest. d. You can also measure areas using the Measure Area tool from the drop down:

7 4. Exploring the Attribute Tables a. Select the Channel_markers layer in the Layer List, and click on the Open Attribute Table icon: A window called Attributes table - Channel_markesr opens. This is the attribute table for your Channel_markers layer. 5. Build a query From the attribute table, you can click on Advanced search (see circled above). The Search query builder window comes up. a. Double-click on ID0. b. Click on LIKE, because you are going to search for all markers that may include the word pylon c. Click on the Sample button, to view a sample of the values in that column field. d. Double-click pylon - Port. See below for illustration. e. Click Test to make sure the syntax is correct. Then click OK.

8 This finds THREE MATCHES that include the word pylon - port in the values of that column field. These are automatically selected, and are highlighted in yellow on the map. 6. Selecting features The select features by rectangle tool can help you find out the attributes of two or more features in a layer at once. a. Close the attribute table if it is still open, and click on the drop down arrow for the select tool. Choose the Select Rectangle Tool b. Click on the Channel_markers layer in the Layer List/Table of contents to select it. c. Draw a box around several channel markers on the map. e. Click on the Open Attribute Table button, and the Channel_markers attribute table opens. All the points that were selected are now highlighted. Explore other tools The two toolbars you have not used yet include: The DIGITIZING toolbar: The Digitizing toolbar is used to create new data ( digitize ) data on your map, or edit existing data. You have the ability to create/revise both spatial data (where a point, line, or polygon data exists), and the attribute/tabular data (the attribute data behind the spatial data).

9 PLUGINS: The Plugins manager (Plugins Manage Plugins) gives you access to many tools that are extensions of QGIS s core functionality Some recommended plugins include: Add Delimited Text Layer o Convert a list of xy coordinates to points GdalTools o Convert between different file types Interpolation plugin o Create a raster surface based on values within a vector point layer Raster Terrain Analysis Tool o Create Slope, Hillshade, and Aspect raster layers from a DEM. Spatial Query Plugin o Make spatial queries to vector data ftools o Adds a suite of geoprocessing tools under the Vector heading in the main applications drop down menus.. Export your map view by going to the File menu Save as Image... and change the File Type to JPG. Create a map layout by going to File New Print Composer This opens the print composer where you can design a map with scalebar, legend, etc. Save your map by going to the File menu Save Project, or by clicking on the Save icon: