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-APPENDIX E - Preparation of the spatial data (input GIS layers)
-This appendix highlight the technical data of the reference system used in the current FFSM version and indicates how to reproduce them, e.g. for countries other than France or for update the Land Cover data.
-Data manipulation can be done using the open source software Quantum Gis (Quantum GIS Development Team, 2012) and Grass (GRASS Development Team, 2012).
-The next table shows the reference system of the spatial data. Their projection match the one of the CLC06 as distributed from the European Environmental Agency.
-^ Parameter   ^ Value                              ^
-| EPSG ID     | 3035                               |
-| projection  | 99 (Lambert Azimuthal Equal Area)  |
-| zone        | 0                                  |
-| datum       | etrs89                             |
-| ellipsoid   | grs80                              |
-| north       | 3168000                            |
-| south       | 1992000                            |
-| west        | 2976000                            |
-| east        | 4512000                            |
-| nsres       | 8000                               |
-| ewres       | 8000                               |
-| rows        | 147                                |
-| cols        | 192                                |
-| cells       | 28224                              |
-===== Common operations required to build the datasets =====
-==== Change a map projection ====
-To reproject  a map (e.g. NUTS) :
-  * Open a map with the target projection in Qgis;
-  * Right click the theme and from the drop-down menu select "use project projection based on this reference system";
-  * Open the shapefile you want to convert;
-  * In the project properties select "on the fly projection";
-  * Save the second shapefile "save as shapefile" and change the projection field option in "project projections".
-=== Clip a shapefile ===
-In order to e.g. clip the CLC06 shapefile only on France borders, the command in QGis is:\\
-Vector → Geo-processing tools → Intersection
-=== Map dissolve ===
-In order to dissolve a shapefile (e.g. to dissolve selected nuts2 for metro France in a single nuts1 map): \\
-Vector → Geo-processing tools → Dissolve\\
-To add to the newly created map the correct area column (in square meters): \\
-Vector → Geometry tools → Add or delete geometric columns
-==== DTM (Digital Terrain Model) ====
-The DTM used derives from the official IGN BD ALTI (modèles numériques de terrain - MNT)  downloaded here: http://professionnels.ign.fr/bdalti#tab-3\\
-The option chosen is the 1000m resolution in format ASC (Télécharger la BD ALTI® 1000 m Métropole (format ASC) (zip, 2,1 Mo)).\\
-The problem is that it comes in RGF93/Lambert-93 projection system (EPSG:2154). To convert it in EPSG:3035 one has to create a GRASS location with the EPSG:2154 projection (source); import the raster data (ESRI ascii format); create an other location with the EPSG:3035 (destination); import in destination the administrative borders; convert the admin borders from vector to raster; use the admin border raster as mark (r.mask); and finally use r.proj to import and reproject from source to dest the dtm file.\\
-Finally the imported dtm can be exported as ascii grid file.
-An alternative very precise DTM dataset for the whole Europe can be downloaded from here:\\
-http://www.eea.europa.eu/data-and-maps/data/eu-dem#tab-european-data
-To fill eventual null values run from GRASS:\\
-''r.fillnulls input=dtm output=dtm_nonulls''\\
-In order to compute the mortality parameters based on regions and elevation run in grass:\\
-''r.mapcalc 'mortality_multiplier200 = if( (regions == 61 || regions == 62 || regions == 81 || regions == 82 || regions == 83 || regions == 71  ) && (dtm_nonulls <= 500), 2.0, 1.0)'''
-==== Maps rasterisation ====
-Start GRASS, choose a folder where to keep your data, and click the Location Wizard to create a new Location. Give it a name and select as method to create the location to specify the reference systems from an EPSG code (e.g. 3035).\\
-To work with the default France data, set the regions details as in Table 20, for all other cases do not set the default region extend and resolution at this time (you'll do later after having imported a shapefile).\\
-Import a vector shapefile having the correct projection and area boundaries (e.g. the nuts of the country under interest).\\
-Set the region to match the newly imported vector map, setting the desired resolution (e.g. 8000) and clicking the option to align the region to resolution.\\
-In order to create the rasters of 8 km with inside the values of the area covered by the  clc06_{311|312|313} layers run the following script:
-<code bash>
-# First set resolution to 20 m..
-g.region -p res=20
-# Now rasterize the vector. This will give you as raster of 20m x 20m with values of 400 where the original vector covered, and null otherwise:
-v.to.rast clc06_311_v out=clc06_311_r20m type=area use=val val=400
-v.to.rast clc06_312_v out=clc06_312_r20m type=area use=val val=400
-v.to.rast clc06_313_v out=clc06_313_r20m type=area use=val val=400
-# Now change back the resolution to 8km..
-g.region -p res=8000
-# Use the "sum" method of r.resamp.stats to get the values for the new, coarse raster. This will leave you with a new raster of res 8km and with values 0-64000000:
-r.resamp.stats clc06_311_r20m out=clc06_311_8km_sqm method=sum
-r.resamp.stats clc06_312_r20m out=clc06_312_8km_sqm method=sum
-r.resamp.stats clc06_313_r20m out=clc06_313_8km_sqm method=sum
-</code>

French Forest Sector Model (FFSM++)

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