GRASS-HRU

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[[Bild:Grasshru.png|thumb|rechts|GRASS-HRU]] The complete process chain for the HRU derivation was implemented according to a service-oriented application in GRASS-GIS. The execution enironment is strictly separated from the operating environment by using a preconfigured, virtual machine which is in charge of data preparation and the calculation of HRUs in GRASS-GIS. A plug-in developed for QGIS creates an intuitive, wizard-driven and transparent environment for the execution of the process chain.
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[[de:GRASS-HRU]]
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[[pt:GRASS-HRU]]
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[[File:Grasshru.png|thumb|rechts|GRASS-HRU]] The complete process chain for the HRU derivation was implemented according to a service-oriented application in GRASS-GIS. The execution environment is strictly separated from the operating environment by using a preconfigured, virtual machine which is in charge of data preparation and the calculation of HRUs in GRASS-GIS. A plug-in developed for QGIS creates an intuitive, wizard-driven and transparent environment for the execution of the process chain.
  
==Download and Installation of GRASS-HRU==
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== Download/Installation of GRASS-HRU==
  
=== Downloading the hard disk image (''Virtual Appliance'') and QGIS-Plugin  ===
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=== Download ===
The following files should be downloaded from http://www.geoinf.uni-jena.de:
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*grass-hru.mf
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*grass-hru.ovf
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*grass-hrus.vmdk
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Together they create a so-called ''Virtual Appliance'' which will be required in the following section.
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In addition, the QGIS plug-in for HRU derivation should be downloaded from the same website:
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*hruwps.zip
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=== Installing the VirtualBox ===
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Use the installation package for a complete and easy installation:
[[Bild:Vbox_setup.jpg|thumb|links|Installation von VirtualBox]]
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The derivation of HRUS with GRASS-GIS, which will be explained below, requires a virtualization software which hosts a linux system and all software and scripts needed. VirtualBox should be used - the current version 3.2.10 can be downloaded at
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http://www.virtualbox.org/wiki/Downloads.
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The wizard leads you through the steps of the installation process. It should be noted that:
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*a temporary deactivation of the network connection is necessary and therefore not unusual
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*all necessary drivers should be installed
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After a successful installation VirtualBox can be launched and the import of a preconfigured hard disk image can start:
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{| class="wikitable"
# Datei -> Appliance importieren
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|-
# Load the Appliance under '''Auswählen''' (see above) (file ''grass-hru.ovf'')<br/>[[Bild:Import_app.jpg]]<br/><br/>
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! !! Download
# Apply the imported configuration of the Appliance and end the import process with '''Abschließen''' <br/>[[Bild:Import_app_2.jpg]]<br/><br/>
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|-
# The appliance is being imported...<br/>[[Bild:Import_app_3.jpg]]<br/><br/>
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| Installer (Windows) || [<!--http://www.geoinf.uni-jena.de/~c3schs/grass-hru/ILMS-3.1.zip-->http://jams.uni-jena.de/ilmswiki/files/ILMS_v3.1_2.zip ILMS_v3.1_2.zip]
# ...and will be available through an entry in the VirtualBox main window (GRASS-HRU 1.0)<br/>[[Bild:Import_app_4.jpg]]<br/><br/>
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|}
  
=== Installing QuantumGIS ===
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(follow the instructions given [[GRASS-HRU_Manual_install|here]] to do a manual installation of GRASS-HRU)
[[Bild:Qgis_setup.jpg|thumb|links|Installation von QunatumGIS]]The current version of QuantumGIS is available at http://www.qgis.org/wiki/Download. The ''Standalone Installer'' is recommended - the download address for version 1.6 is http://qgis.org/downloads/QGIS-OSGeo4W-1.6.0-14615-Setup.exe.
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Please note: For the HRU derivation the GRASS plug-in for QuantumGIS is not required but it is included in the installer version 1.6. As an alternative, the installer version 1.4 of QuantumGIS can be used, which does not install a GRASS plug-in and therefore reduces the filesize. (http://qgis.org/downloads/QGIS-1.4.0-1-No-GrassSetup.exe)
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===Installing the Plug-in===
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=== Installation ===
To install the actual plug-in for HRU derivation in QuantumGIS the following steps have to be followed:
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For installing the GRASS-HRU software package, please follow these steps:
# Unzip the zip archive ''hruwps.zip'', which has been dowloaded (see above), into the plug-in file of QuantumGIS. According to the QuantumGIS version the folder is called
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# Unpack the downloaded GRASS-HRU archive in your desired location
#*../QuantumGIS/python/plugins ''oder''
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# <span style="color:red;">Currently, the automatic detection of 32/64 bit system failed in some cases - so it is recommended to edit the setup.cfg manually ("version" in section "general": "32bit" or "64bit")</span> 
#*../QuantumGIS/apps/qgis/python/plugins
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# Choose the setup file (setup.exe) and execute it as an administrator (right click the file -> Execute as Administrator)
# QuantumGIS starten
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# Whenever asked for permission to install software/drivers during setup, please confirm
# Plugins -> Plugins verwalten<br/>[[Bild:Qgis_plugin_2.jpg]]<br/><br/>
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# During installation, you are prompted to restart the computer – please quit setup, reboot and restart the setup script (with administrator rights) again
# Im ''QGIS Plugin Manager'' nach ''HRU WPS-Client'' suchen, aktivieren und mit '''Ok''' bestätigen <br/>[[Bild:Qgis_plugin.jpg]]<br/><br/>
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# Once the installation has finished, close the installer by pressing the "exit setup" button
# Das Tool zur HRU-Ableitung kann nun über einen separaten Button in der Menüleiste gestartet werden<br/>[[Bild:Qgis_plugin_3.jpg]]<br/><br/>
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==Vorbereitung==
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==Starting GRASS-HRU==
Bevor mit der HRU-Ableitung begonnen werden kann, muss sichergestellt sein, dass folgende Punkte abgearbeitet wurden:
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In order to start the HRU delineation process, please start GRASS-HRU as follows:
# Start der neu angelegten ''Virtual Appliance'' mit dem Namen "GRASS-HRU 1.0" durch Doppelklick auf den entsprechenden Eintrag im VirtualBox-Fenster (bzw. Schaltfläche "Starten"). Der darauf startende Boot-Vorgang im separaten Fenster sollte abgewartet werden und kann bei Erscheinen des Login-Prompts minimiert werden ('''nicht''' schließen!). Die virtuelle Maschine läuft während der gesamten HRU-Ableitung im Hintergrund.<br/>[[Bild:Start_app_1.jpg]]<br/>Hinweis: Durch Eingabe von http://localhost in die Adresszeile eines Internetbrowsers kann überprüft werden, ob die virtuelle Maschine erfolgreich gestartet werden konnte und eine Verbindung zu ihr möglich ist. Eine Internetseite mit dem Schriftzug "It works!" sollte geladen werden.
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# Im Windows-Dateiexplorer auf ''Extras -> Netzlaufwerk verbinden'' klicken und als Ordner '''http://localhost/in''' eintragen. Außerdem einen freien Laufwerksbuchstaben auswählen, z.B. '''Z:'''<br/>[[Bild:Start_app_2.jpg]]<br/><br/>In diesem Ordner sind nun alle Eingangsdaten abzulegen. Das bereits existierende Unterverzeichnis ''/gehlberg'' enthält Beispieldaten sowohl für Eingangs- als auch Ergebnislayer. In dem neuen Netzwerkordner können nach Belieben eigene Unterordner für die benötigten Eingangsdaten angelegt werden.
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# From the GRASS-HRU installation folder, please start the GRASS-HRU Launcher by double-clicking GRASS-HRU.exe
# Jetzt kann das Plugin aus QuantumGIS heraus gestartet werden. Hierfür QuantumGIS starten und auf das GRASS-HRU-Icon (siehe oben) klicken - das Plugin für die HRU-Ableitung wird geöffnet. Ein Klick auf das Lupen-Icon rechts neben der Adresszeile sollte eine erfolgreichen Meldung über die Verbindung liefern.<br/>[[Bild:Grass_hru_1.jpg]]<br/><br/>
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# From the menu bar, start the GRASS server appliance by clicking the green start icon and wait, until the appliance has fully booted
==Details zur HRU-Ableitung unter Verwendung des Wizards==
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# Press the GRASS-HRU@QGIS button to launch the bundled QGIS version
===Schritt 0: Setup===
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# Activate the GRASS-HRU plugin in QGIS by following these steps:
*Auswahl des digitalen Geländemodells (DGM) im GeoTiff-Format sowie eines Pegeldatensatzes im Shapefile-Format, jeweils über den ''Datei''-Button neben dem Eingabefeld.
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#* choose "Plugins -> Manage Extension..." from the QGIS menu
*Auswahl zusätzlicher Datenlayer (Landnutzung, Boden, Geologie) durch den ''Hinzufügen''-Button rechts neben der ''Data Layer'' Tabelle.
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#* tick the checkbox in front of GRASS-HRU
*Aufziehen einer Bounding-Box (erster Links-Klick: Eckpunkt links oben, zweiter Links-Klick: Eckpunkt rechts unten, Rechtsklick: Bounding-Box löschen). Die entstandene Bounding-Box sollte das komplette, zu untersuchende Einzugsgebiet umschließen.
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# Start the GRASS-HRU wizard by choosing its launcher button from the toolbar: [[File:Grasshru.png|30x30px|text-bottom]]
[[Bild:Grass_hru_2.jpg]]
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# After you have finished using GRASS-HRU, stop the GRASS server appliance by clicking the red stop button
===Schritt 1: Preparation===
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*Es besteht die Möglichkeit, lokale Senken im DGM zu entfernen. Falls das vorliegende DGM noch nicht gefüllt wurde, ist ''default filling'' aus der Methodenliste auszuwählen.
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==Details on the HRU Derivation Using the Wizard==
*Für die zu berechnende Hangneigung und Hangausrichtung sind keine weiteren Eingaben nötig.
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===Step 0: Setup===
[[Bild:Grass_hru_3.jpg]]
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*Selection of the digital terrain model (DGM) in GeoTiff format and a shapefile format, each by using the button ''Datei'' next to the input field.
===Schritt 2: Reclass===
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*Selection of additional data layers (land use, soil, geology) by clicking on the add button on the right hand side of the ''Data Layer'' chart. For each of the entries, right click it and choose the appropriate parameter file name
*Über die verschiedenen Reiter (DEM, Slope und Aspect) erfolgt die Klassifikation der entsprechenden Karte.
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*Opening a  bounding box (first left mouse click: top left-hand corner, second left mouse click: bottom right-hand corner, right mouse click: delete bounding box). The resulting bounding box should comprise the complete catchment area to be analysed.  
*Die Standardbereiche bzw. -werte können jeweils übernommen oder angepasst werden. Im Falle einer Modifizierung ist darauf zu achten, dass die jeweiligen Minima und Maxima nicht unter- bzw. überschritten werden.
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[[File:Grass_hru_2.jpg]]
*Soll ein Datensatz nicht in HRU-Ausweisung einfließen, so kann dieser abgewählt werden (Checkbox ''not required'').
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[[Bild:Grass_hru_4.jpg]]
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===Step 1: Preparation===
===Schritt 3: Waterflow===
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*It is possible to delete local sinks from the DGM. In case the current DGM has not been filled yet, ''default filling'' should be selected from the methodology list.
*Zur Ableitung des Gewässernetzes, der Fließakkumulation und -richtung sowie der Teileinzugsgebiete ist die Eingabe eines Schwellenwerts ''Minimum Size Of Basins'' erforderlich.
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*For the calculation of slope and slope orientation no further input is necessary.
*Dieser Parameter bestimmt u.a. den Detailgrad des Gewässernetzes bzw. die Anzahl der Teileinzugsgebiete. Der Schwellenwert legt die Größe des kleinsten, abzuleitenden Teileinzugsgebiets fest und ist in Zellen (Pixelanzahl) anzugeben.
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[[File:Grass_hru_3.jpg]]
*Beispiel: Ein Wert von 1500 (und eine angenommene Auflösung von 25m) führt zur Ausweisung von Teileinzugsgebieten größer als (1500*25*25)/1000000 = 0.9375km² ~ 1km².   
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[[Bild:Grass_hru_5.jpg]]
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===Step 2: Reclass===
===Schritt 4: Outlet Watersheds===
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*According to the different indices (DEM, Slope and Aspect) the corresponding map is classified.
*Folgende Teilschritte sind für die Berechnung einer Karte der an Pegeln abgeleiteten Teileinzugsgebiete notwendig:
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*The standard areas and values can be applied or modified. In case of a modification values cannot be below or above the corresponding minima and maxima.  
*#Pegel- und Gewässernetzkarte ganz nach oben in der Legende verschieben, so dass beide Datensätze sichtbar werden.
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*If a data set should not be used for HRU derivation, it can be deselected (Checkbox ''not required'').
*#Mit dem Zoom-Werkzeug überprüfen, ob die einzelnen Pegel exakt auf dem abgeleiteten Gewässernetz liegen. Falls nicht, mit Hilfe des Werkzeugs zum Verschieben von Vektorpunkten den Pegel-Layer so abändern, dass '''alle Pegel im Einzugsgebiet''' auf den Gewässerabschnitten liegen. Dafür wie folgt vorgehen:
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[[File:Grass_hru_4.jpg]]
*##Pegel-Layer in der Legende markieren und Vektor-Bearbeitungsmodus [[Bild:Qgis_tool_1.jpg|30px]] von QuantumGIS aktivieren
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*##Tool zum Verschieben von Vektorpunkten [[Bild:Qgis_tool_2.jpg|30px]] starten und Pegel auf die entsprechenden Gewässerabschnitte verlegen
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===Step 3: Waterflow===
*##Zum Abschluß den Bearbeitungsmodus durch erneutes Klicken auf [[Bild:Qgis_tool_1.jpg|30px]] verlassen und das Speichern der Änderungen bestätigen
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*For the derivation of the water supply network, flow accumulation and flow direction and for partial catchment areas a threshold value ''Minimum Size Of Basins'' is required.
*#Haben alle Pegel im Einzugsgebiet die korrekte Position auf dem Gewässernetz, müssen die für die Berechnung relevanten Pegel schließlich markiert werden - hierfür das Markierungs-Werkzeug [[Bild:Qgis_tool_3.jpg|30px]] verwenden.
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*This parameter determines, for example, the degree of detail of the water network or the number of partial catchment areas. The threshold value determines the smaller, derivable partial catchment area and is indicated in cells (number of pixels).
*In der Auswahlliste ''Name of corresponding attribute (ID)'' die Bezeichnung des Shapefile-Attributes wählen, welches eine eindeutige Kennziffer ('''ganzzahlig und > 0''', z.B. Pegel-ID) für jeden Pegel repräsentiert.
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*Example: A value of 1500 (and an assumed solution of 25m) results in a designation of partial catchment areas bigger than (1500*25*25)/1000000 = 0.9375km² ~ 1km².   
[[Bild:Grass_hru_6.jpg]]
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[[File:Grass_hru_5.jpg]]
===Schritt 5: Overlay===
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*Bei der Verschneidung aller Datenlayer (bestimmte Layer können durch Abwählen auch unberücksichtigt bleiben) entstehen Kleinstflächen, welche als HRUs ungeeignet sind und deswegen eliminiert werden sollten.
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===Step 4: Outlet Watersheds===
*Zu diesem Zweck wird ein Schwellenwert definiert (''Size of smallest area to remove''), welcher die Minimumgröße einer HRU (in Zellen) festlegt.
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*The following steps are necessary for the calculation of a map showing partial watersheds derived from their water levels:
*Beispiel: Ein Wert von 8 (und eine angenommene Auflösung von 25m) führt zur Ausweisung von HRUs, welche größer als (8*25*25) = 5000m² =0.5ha sind. 
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*#Pan the water level and supply map up in the key, so both data sets are visible.
[[Bild:Grass_hru_7.jpg]]
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*#Check with the zoom tool whether the singular water levels lie exactly on the derived water supply network. If not, modify the level layer until '''all levels in the watershed''' lie on the water sections. To do so, please proceed as follows:  
===Schritt 6: Topology===
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*##Select the level layer on the key and activate the vector editing mode of QuantumGIS [[File:Qgis_tool_1.jpg|30px]]  
*Für die Bestimmung der topologischen Verknüpfung von HRUs (und Gewässersegmenten) ist keine gesonderte Parametereingabe erforderlich.
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*##Take the tool for panning vector points [[File:Qgis_tool_2.jpg|30px]] and relocate the corresponding watersheds
*Das Modul berechnet
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*##Finally, cancel the edit mode by clicking on [[File:Qgis_tool_1.jpg|30px]] again and agree to save changes
**die N:1 Topologie (HRUs können in nur eine benachbarte HRU/einen Gewässerabschnitt entwässern)
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*#If all water levels in the catchment area have the correct position in the water network, those levels relevant to the calculation have to be selected - use the marker tool [[File:Qgis_tool_3.jpg|30px]].  
**die N:M Topologie (HRUs können in mehrere benachbarte HRUs/Gewässerabschnitte entwässern)
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*Choose the shapefile attribute on the selection list ''Name of corresponding attribute (ID)'' which represents a unique parameter for the level ('''integer and > 0''', e.g. level ID).  
**die Gewässertopologie (topologische Verknüpfung aller Gewässersegmente)
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[[File:Grass_hru_6.jpg]]
*Die Option ''Enable discrete reaches'' ist eine Erweiterung des Verfahrens zur Topologie-Ableitung und momentan in der Entwicklung noch nicht abgeschlossen.
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[[Bild:Grass_hru_8.jpg]]
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===Step 5: Overlay===
===Schritt 7: Statistics===
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*The intersection of all data layers creates small areas (specific layers can be disregarded by deselecting them). Those areas are not suitable as HRUs and should therefore be eliminated.
*Die bis hierher im Rasterformat vorliegende HRU-Karte (GeoTiff) wird in diesem Schritt in ein Shapefile konvertiert, wobei ausgewählt werden kann, welche zusätzlichen Eigenschaften einer einzelnen HRU in die Attributtabelle übernommen bzw. berechnet werden sollen.
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*For this purpose a threshold value is defined (''Size of smallest area to remove'') which determines the minimum size of an HRU (in cells).
[[Bild:Grass_hru_9.jpg]]
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*Example: A value of 8 (and an assumed solution of 25m) results in a designation of HRUs which is bigger than (8*25*25) = 5000m² =0.5ha  
 +
[[File:Grass_hru_7.jpg]]
 +
 
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===Step 6: Topology===
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*For the determination of the topological connection of HRUs (and water segments) no specific parameter input is necessary.
 +
*The module calculates
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**the N:1 topology (HRUs can drain in only one neighboring HRU/river section)
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**the N:M topology (HRUs can drain in several neighboring HRUs/river sections)
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**water topology (topological combination of all river sections)
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*The option ''Enable discrete reaches'' is an extension of the topological derivation and its development has not yet been finished.
 +
[[File:Grass_hru_8.jpg]]
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===Step 7: Statistics===
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*The existing HRU map in grid format (Geo Tiff) is now converted into a shapefile. In doing so, additional features of a single HRU can be selected which are taken to the attribute chart or are supposed to be calculated.  
 +
[[File:Grass_hru_9.jpg]]

Latest revision as of 19:05, 4 March 2019

GRASS-HRU
The complete process chain for the HRU derivation was implemented according to a service-oriented application in GRASS-GIS. The execution environment is strictly separated from the operating environment by using a preconfigured, virtual machine which is in charge of data preparation and the calculation of HRUs in GRASS-GIS. A plug-in developed for QGIS creates an intuitive, wizard-driven and transparent environment for the execution of the process chain.

Contents

Download/Installation of GRASS-HRU

Download

Use the installation package for a complete and easy installation:

Download
Installer (Windows) ILMS_v3.1_2.zip

(follow the instructions given here to do a manual installation of GRASS-HRU)

Installation

For installing the GRASS-HRU software package, please follow these steps:

  1. Unpack the downloaded GRASS-HRU archive in your desired location
  2. Currently, the automatic detection of 32/64 bit system failed in some cases - so it is recommended to edit the setup.cfg manually ("version" in section "general": "32bit" or "64bit")
  3. Choose the setup file (setup.exe) and execute it as an administrator (right click the file -> Execute as Administrator)
  4. Whenever asked for permission to install software/drivers during setup, please confirm
  5. During installation, you are prompted to restart the computer – please quit setup, reboot and restart the setup script (with administrator rights) again
  6. Once the installation has finished, close the installer by pressing the "exit setup" button

Starting GRASS-HRU

In order to start the HRU delineation process, please start GRASS-HRU as follows:

  1. From the GRASS-HRU installation folder, please start the GRASS-HRU Launcher by double-clicking GRASS-HRU.exe
  2. From the menu bar, start the GRASS server appliance by clicking the green start icon and wait, until the appliance has fully booted
  3. Press the GRASS-HRU@QGIS button to launch the bundled QGIS version
  4. Activate the GRASS-HRU plugin in QGIS by following these steps:
    • choose "Plugins -> Manage Extension..." from the QGIS menu
    • tick the checkbox in front of GRASS-HRU
  5. Start the GRASS-HRU wizard by choosing its launcher button from the toolbar: Grasshru.png
  6. After you have finished using GRASS-HRU, stop the GRASS server appliance by clicking the red stop button

Details on the HRU Derivation Using the Wizard

Step 0: Setup

  • Selection of the digital terrain model (DGM) in GeoTiff format and a shapefile format, each by using the button Datei next to the input field.
  • Selection of additional data layers (land use, soil, geology) by clicking on the add button on the right hand side of the Data Layer chart. For each of the entries, right click it and choose the appropriate parameter file name
  • Opening a bounding box (first left mouse click: top left-hand corner, second left mouse click: bottom right-hand corner, right mouse click: delete bounding box). The resulting bounding box should comprise the complete catchment area to be analysed.

Grass hru 2.jpg

Step 1: Preparation

  • It is possible to delete local sinks from the DGM. In case the current DGM has not been filled yet, default filling should be selected from the methodology list.
  • For the calculation of slope and slope orientation no further input is necessary.

Grass hru 3.jpg

Step 2: Reclass

  • According to the different indices (DEM, Slope and Aspect) the corresponding map is classified.
  • The standard areas and values can be applied or modified. In case of a modification values cannot be below or above the corresponding minima and maxima.
  • If a data set should not be used for HRU derivation, it can be deselected (Checkbox not required).

Grass hru 4.jpg

Step 3: Waterflow

  • For the derivation of the water supply network, flow accumulation and flow direction and for partial catchment areas a threshold value Minimum Size Of Basins is required.
  • This parameter determines, for example, the degree of detail of the water network or the number of partial catchment areas. The threshold value determines the smaller, derivable partial catchment area and is indicated in cells (number of pixels).
  • Example: A value of 1500 (and an assumed solution of 25m) results in a designation of partial catchment areas bigger than (1500*25*25)/1000000 = 0.9375km² ~ 1km².

Grass hru 5.jpg

Step 4: Outlet Watersheds

  • The following steps are necessary for the calculation of a map showing partial watersheds derived from their water levels:
    1. Pan the water level and supply map up in the key, so both data sets are visible.
    2. Check with the zoom tool whether the singular water levels lie exactly on the derived water supply network. If not, modify the level layer until all levels in the watershed lie on the water sections. To do so, please proceed as follows:
      1. Select the level layer on the key and activate the vector editing mode of QuantumGIS Qgis tool 1.jpg
      2. Take the tool for panning vector points Qgis tool 2.jpg and relocate the corresponding watersheds
      3. Finally, cancel the edit mode by clicking on Qgis tool 1.jpg again and agree to save changes
    3. If all water levels in the catchment area have the correct position in the water network, those levels relevant to the calculation have to be selected - use the marker tool Qgis tool 3.jpg.
  • Choose the shapefile attribute on the selection list Name of corresponding attribute (ID) which represents a unique parameter for the level (integer and > 0, e.g. level ID).

Grass hru 6.jpg

Step 5: Overlay

  • The intersection of all data layers creates small areas (specific layers can be disregarded by deselecting them). Those areas are not suitable as HRUs and should therefore be eliminated.
  • For this purpose a threshold value is defined (Size of smallest area to remove) which determines the minimum size of an HRU (in cells).
  • Example: A value of 8 (and an assumed solution of 25m) results in a designation of HRUs which is bigger than (8*25*25) = 5000m² =0.5ha

Grass hru 7.jpg

Step 6: Topology

  • For the determination of the topological connection of HRUs (and water segments) no specific parameter input is necessary.
  • The module calculates
    • the N:1 topology (HRUs can drain in only one neighboring HRU/river section)
    • the N:M topology (HRUs can drain in several neighboring HRUs/river sections)
    • water topology (topological combination of all river sections)
  • The option Enable discrete reaches is an extension of the topological derivation and its development has not yet been finished.

Grass hru 8.jpg

Step 7: Statistics

  • The existing HRU map in grid format (Geo Tiff) is now converted into a shapefile. In doing so, additional features of a single HRU can be selected which are taken to the attribute chart or are supposed to be calculated.

Grass hru 9.jpg

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