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--- introgis [2019/11/11 16:45]
qcbs [Exercise 6 - Using GRASS within QGIS]
+++ introgis [2019/11/12 17:17] (current)
qcbs [Exercice 4 - Downloading files, recap and challenge!]
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 **CHALLENGE 2**: Regenerate your interpolated raster maps for each time periods using the Multi-level B-Spline Interpolation tool in Saga. Use the Processing toolbox for this. Compare those maps with the ones you obtained with Inverse Distance Weighting.
 ====== Exercice 4 - Downloading files, recap and challenge! ======
-For this exercise, you will need to extract the mean elevation and the land cover at occurence sites of the [[http://www.gbif.org/|Global Biodiversity Information Facility (GBIF)]] falling within the Wemindji aboriginal territory, in the James Bay area of Quebec. **You will want to work with the UTM Zone 17N / NAD83 reference system**. Note that to reproject a raster, the preferred way is to use Raster>Projections>Warp.To achieve the objective, you will need to complete the following steps:
+For this exercise, you will need to extract the mean elevation and the land cover at occurence sites of the [[http://www.gbif.org/|Global Biodiversity Information Facility (GBIF)]] falling within the Wemindji aboriginal territory, in the James Bay area of Quebec. **You will want to work with the UTM Zone 17N / NAD83 reference system**. Note that to reproject a raster, the preferred way is to use Raster>Projections>Warp. To achieve the objective, you will need to complete the following steps:
-  * On the [[http://open.canada.ca/|Canada Open Government]] website, download raster [[http://ftp.geogratis.gc.ca/pub/nrcan_rncan/elevation/cdem_mnec/|elevation files]] for zones 33D and 33E at the 1:250,000 scale.
+  * On the [[https://open.canada.ca/en/open-data|Canada Open Government]] website, download raster [[http://ftp.geogratis.gc.ca/pub/nrcan_rncan/elevation/cdem_mnec/|elevation files]] for zones 33D and 33E at the 1:250,000 scale.
   * Download this {{::qc_land_use_33de.zip|ZIP package}} containing a tif file with a recent land cover classification of the area and the associated style/colormap in qml format.
-  * On Open Government website, download the shapefile of Aboriginal Lands of Canada Legislative Boundaries (al_ta_ca_shp_gdm_en.zip). The shapefile of interest is the one that ends with _MODIFIED
+  * On the MERN website (https://mern.gouv.qc.ca/territoire/portrait/portrait-donnees-mille.jsp), download the "Découpages administratifs", "Municipalités, TNO et territoires autochtones" dataset as a shapefile. You will want the polygon layer.
   * Download {{::occurrence.txt|this file}} containing the [[http://www.gbif.org/|GBIF]] species occurences in the Wemindji region. Note that this file is TAB delimited and the coordinates are in Latitude, longitude (WGS84). You can open it in a text editor to explore it's content.
-  * Using the latitude, longitude coordinates, add the GBIF occurences to the map canvas.
+  * Using the latitude, longitude coordinates, add the GBIF occurences to the map canvas (it is TAB delimited).
   * Merge the elevation raster layers (.tif) into one using Raster>Miscellaneous>Merge. Save the output as a .tif file.
+  * Use a filter to isolate the Wemindji territory (MUS_MN_MUN column)from the municipalities layer.
   * Clip the occurrences to obtain only those within the Wemindji territory.
   * Use the 'point sampling tool' plugin to extract the name of each species in latin, the land cover and the elevation at each occurrence location. Note that some locations contain a large number of occurrences.
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 Use the Cluster Analysis for Grids function in Processing Toolbox>SAGA to perform an unsupervised classification of your images using bands 3,4,5 and 7.
-====== Exercise 6 - Using GRASS within QGIS Processing toolbox ======
+====== Exercise 6 - Using GRASS with QGIS Processing toolbox ======
 Objective: Isolate the largest contiguous patch of land that is not covered by water and that is at least 1km from roads.
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 **Step 1**: Save the file routes.shp as a new layer with the CRS NAD83 / UTM 18N. Do the same for the Region_Hydrique shapefile.
-**Step 2**: Convert the routes and the Region_Hydrique files to raster format using the v.to.rast function. Choose the "Source for raster values" as "va", and put 1 in the "Raste vale (use=val). Do the same for the regions hydriques.
+**Step 2**: Convert the routes and the Region_Hydrique files to raster format using the v.to.rast function. Choose the "Source for raster values" as "va", and put 1 in the "Raster value (use=val)". Do the same for the regions hydriques.
 **Step 3**: Use the r.grow.distance function to create a continuous raster map in which each pixel is assigned the distance from the closest route. Use the routes layer in raster format (Step 6) as the input.