02/02/2010
GIS REPORT - TEAM SIX
Table of contents
o Digital Elevation Model
o Hydrology Processing
o Landuse Analysis
o Result
1
02/02/2010
Digital Elevation Model
ARC Catalog
Tin
(1/2)
75x75
Open topo75.txt and create a “Feature to
Class”.
.
ARC Map
Tinée
In Arc toolbox, made a Feature to Raster
and specified the good number of cell
size. In this case: 75.
Then, we have our DEM in 75 definition.
In order to obtain our TIN, use the Raster
to Tin tool in the 3D Analysis Toolbox.
We can also done this manipulation for
the topo300.txt file. In order to compare
75 and 300 definition.
Vésubie
Up Var
Elevation (meters)
Edge type
2500 - 3000
2000 - 2500
Down Var
1500 - 2000
1000 - 1500
800 - 1000
0
7,500
15,000
30,000 Kilometers
500 - 800
200 - 500
100 - 200
4 - 100
Digital Elevation Model
DEM
1
Estéron
(2/2)
75 x 75
.
Tinée
Vésubie
Up Var
DEM
Estéron
High : 3000 meters
Down Var
0
7,500
15,000
Low : 4 meters
30,000 Kilometers
Photos : http://www2.alpes-maritimes.equipement.gouv.fr
2
02/02/2010
Hydrology Processing
Fill Sink (1)
• A low pressure area is an area for which
the altitude of points surrounding the area
are higher: natural phenomenon or error
digital terrain model.
Flow Direction (2)
• In the Terrain Processing Tool, use the “Flow
Direction” Tool to obtain this map.
•Requires a Digital Terrain Model in data entry.
Produces as output a grid of integer values
representing directions
flows.
Hydrology Processing
Flow Accumulation (3) Stream Definition (4)
• Input parameters for Flow Accumulation:
- Matrix management of flows: the careful direction of flow
must have been calculated using the corrected DTM wells
- Weighting Matrix: This is an optional grid which assigns
weighing cells
• Calculate the flow accumulation in each cell.
Segmentation (5)
• Input data for Stream Definition:
- Matrix management of runoff
- Matrix accumulation of runoff
3
02/02/2010
Hydrology Processing
Catchment Grid Delineation (6) Catchment Polygon Processing (7)
Hydrology Processing
Drainage line processing (8)
•
Drainage point processing (9)
In the Terrain Processing Toolbox, use
the Drainage line processing Tool.
• In the Terrain Processing Toolbox,
use the Drainage point Tool using
the previous create file.
• Select the point corresponding at
each sub catchment.
4
02/02/2010
Hydrology Processing
•
At this moment of the processing, we
have to re start all the step in order to
obtain the good Stream, segmentation
stream and Polygon Catchment.
•
So, re start with the step number (4).
After done all this step we can calculate
the Longest Flow Path. For this, we have
to use in “Terrain Processing” the
“Longest Flow Path for Catchment” tool.
Watershed (10)
Keep the selection on the Drainage point
file and use the “Watershed” Tool in
“Spatial Analysis” Toolbox to obtain our
five Catchment.
.
Tinée
!
!
Vésubie
Up Var
!
Tinée
Up Var
Estéron
!
!
Vésubie
Estéron
Down Var
!
Down Var
Stream
0
7,500
15,000
30,000 Kilometers
!
Station
Landuse Analysis
Few step...
• Transform the Landuse_legend.txt file
in dbf. After this you can give coordinate
(X;Y) at your file. Right clic on the folder,
“Display XY Data”.
• Open the Varveg300.asc file. If you are
some problem to open this file open it
with a note pad and check the 2 first
line, compare it with the topo300.asc file.
• After that, you can join the two table
with a similar ID. In this case:
LABEL_LEVEL
5
02/02/2010
Table Result
Land use Result
% of global catchment
Tinée
Artificial area
0,822258342
Agricol area
4,366255537
Forest and semi naturel area
94,59476687
Wet land
0,082863244
Water bodies
0,133856009
Total
100
Artificial area (m²)
Agricol area (m²)
Forest and semi naturel
area (m²)
Wetland (m²)
Water bodies
(m²)
Area (m²)
1477504,8
4728015,36
608805852,8
0
295500,96
615306874
889827266
Upper Var
1994631,48
29919472,2
856583407,8
1329754,32
0
Vésubie
1625255,28
27924840,72
336353967,7
73875,24
0
365977939
Down Var
12041664,12
28072591,2
83552896,44
0
2733383,88
126400536
Estéron
1920756,24
10564159,32
307394873,6
517126,68
73875,24
320470791
Total
19059811,92
101209078,8
2192690998
1920756,24
3102760,08
2317983405
Table Result
Longest Flow Path / Slope Result
Longest Flow Path (km)
Tinée
67,48
Upper Var
85,36
Vésubie
46,22
Down Var
36,48
Estéron
58,14
Slope catchment (mean %)
Slope Stream (%)
Tinée
38,3
3,1
Upper Var
31,8
2,4
Vésubie
37,2
4,9
Down Var
22,14
2,5
Estéron
25,4
2,2
6