This channel contains Open Educational Resources (OER) on open source GIS, made by Hans van der Kwast. Hans is an Associate Professor of Open Science and Digital Innovation at IHE Delft Institute for Water Education (www.un-ihe.org) and owner of QWAST-GIS (www.qwast-gis.com).
The channel also contains videos of the exercises in the book "QGIS for Hydrological Applications - Recipes for Catchment Hydrology and Water Management" by Kurt Menke and Hans van der Kwast. More information about the book can be found at the website of Locate Press: www.locatepress.com/hyd2.
Free step-by-step tutorials can be found at the GIS OpenCourseWare Platfrom: courses.gisopencourseware.org
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If you need more personal help, you can now join as a GeoGenius member of my channel!
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must clip the sea area?
Always good to mask water bodies.
Thanks for this tutorial. Don´t you know how to Tile pointcloud and name it according to atribute of clipping/tiling polygon?
Hello, I'm having some issues using the 'upslope area' tool. I'm using QGIS 3.28.11 and have gotten the error " SAGA version 7.8.2 is not officially supported - algorithms may encounter issues". Is there another way for me to delineate the catchment using a different tool? Thank you for all of your helpful content
I switched to the PCRaster Tools plugin. Check my videos about that. It's more robust than SAGA. If you srill want to use SAGA, check my work around videos.
@@HansvanderKwast Thank you very much!
First of all thanks very much for this amazing tutorial. I want to do the same analysis for an area in Germany, but I could not find DTM and DSM with higher resolution than 30m. Would this type of analysis work with such resolutions?
Que interesante. Se puede exportar el video???😊
Yes, from the temporal controller you can export the frames as PNG and create an animated GIF in GIMP. See kzread.info/dash/bejne/X4GkxtWqkrTZibw.html&si=Mqisis_0hOIEaDTC
Hello. I am trying to do something similar to this but with many more points (about 5000). Memory-wise, it is not feasible to load each layer and merge into one file. All I need is the resulting attribute table with costs and ideally distances of all the paths. I can save each path as individual files without loading them, but I was wondering if you have further suggestions on how to approach this issue.
Update: I was able to merge the files in Python and subsequently work with the merged dataframe in Q
Hi Hans, when I create a new attribute table, it is not editable. How can I solve this?
Hi. The problem with the RAT is know and fixed. It will be working in the next release. See github.com/qgis/QGIS/issues/57795.
When I use the raster calculator in the model designer it always shows seven layers named A, B, C, D, E, F, G. But not the actual layers like shown on your video. Why does it do this? A works in the calculations, but only if it is the only raster input in that line of algorithms. How do I get it to show the correct raster layers in the raster calculator?
Great help for learner, thank you sir
How to download point of interest ? and how to handle data
Hello, thank you for all your videos they have been a great help. My first hurdle is my Raster attribute table has the edit toggle greyed out. I also am getting an error when trying to us the Lookup tool, resulting in no excel sheet produced. Do you have any solutions? thank you
Hi. The problem with the RAT is know and fixed. It will be working in the next release. See github.com/qgis/QGIS/issues/57795. Lookup tool reads a lookuptable in text format, not Excel and it is an input. The result is a reclassified raster. Lookup table from RAT exports the RAT to a text file in the lookup table format.
Thank you
Please Professor, how do we calculate knickpoints from a DEM during drainage or stream analysis? Thank you
Thank you for putting all this together for us. Let God continue to empower you. Please can someone help me with a link to generate 'knickpoints' in stream analysis ?
Why can’t I set a non-integer level elevation value in the raster calculator? For example, a request less than 1 meter is possible, but less than 1.3 is not possible. and how to solve this problem
It should work, but note that the result is Boolean: "DTM_voidsremoved@1" <= 1.3 will result in pixels with 1 (True) for elevations less than or equal to 1.3. Other pixels will have value 0 (False).
Concerning geopackage, is it possible to create and stores relations 1/N? I was able to do it in filegeodatabase, but would prefer with geopackage. Thanks
I haven't tried it myself, but it should work.
@@HansvanderKwast Looks there is something wrong; does not offer a straight procedure with GUI, done in that environment (SQLite/GeoPackage).
Hi Hans, is it perhaps possible to use plugins from a new version 3.32 into an older version (mine is now 3.28) ? It always takes me so much time download & customize a new version and then re-install the plugins and add them to my toolbars New versions come out very often and I don't want to keep re-installing QGIS and go through the same process I would like to use the point cloud conversion plugins (from 3.32) as per your example but I don't know if that is easily done? I suspect there is an easier way to download a new version of QGIS and still be able to keep all toolbars and settings, perhaps an idea for a video ? Thanks for your great videos
QGIS installations share the location of your profile. Your profile stores your plugins amongst other settings. See kzread.info/dash/bejne/n3-ItKqFZbyymqw.htmlsi=bCjHsy5H-h60jtMf. Only if your plugin is not supported by the QGIS version, it will not load. The point cloud tools in the video are core functionality, so you can only use those tools from 3.32.
it takes 2 minutes to make a map....and one weak to solve all the errors this program gives!!
Note that these tools are now available in the PCRaster Tools plugin. Please let me know what problems you face, so I can provide guidance.
@@HansvanderKwast hi sir, I ,managed to solve all my errors. I udpsed the ldd layer and the DP second layer I used a rusle map because I needed the sediment yield in my basin. But the final map was not good. I had parts in the map completely missing. The river, where the flow should have been, was completley missing from the map. Like pixels weren't there.,,,idk what happened or what I did wrong
@@inmintealucagula Are you sure you're not using a Geographic Coordinate System (e.g. EPSG:4326 - Lat/Long)?
@@HansvanderKwast what do you mean, sir? It has something to do with the coordonate system?
Hey Hans, I have a bit of a video request, would you be able to show us how to do a dam-break model in HEC-RAS using QGIS for the topography files and such. Would be awesome if somebody finally explained in plain clear english what needs to be done! - Isaac
Hi . Thank you for sharing this amazing information . Im new to WebODM . I wanna buy the software . And Im not sure if its going to work offline without internet ! Somtime I travel for long distances fo remote area . And I dont have any link . Is this software can works also by offline situations?
Hi. You can install it on a laptop and use it offline. Basically it runs a server locally. Instructions are here: kzread.info/dash/bejne/fohkxrt8mJvWiNo.html
A lot of time wasted seen tons of other explanations.... this is THE REAL THING !! best.... thanks...!!
how it is possible to add some country in WEB tab? I saw that you have Georgia country, how can I use?
Here the layers come from the QuickMapServices plugin. They provide specific layers, see nextgis.com/blog/quickmapservices/
Lo hice y quedó perfecto, solo que tuve un inconveniente con relacion a el paso de (spatial), lo arreglé no guardando la capa temporal, al igual con la herramienta accuflux, tambien le puse una simbología de 1000 y quedó perfecta. Muchas gracias maestro!! :) saludos desde Guatemala.
Excuse me can I know what is the name of the algorithm used in this tutorial, please?
Here's the link to the r.carve tool from GRASS that was used: grass.osgeo.org/grass83/manuals/r.carve.html
Great tutorial, ty so much!
When I install the "QGIS PCRaster model collection" I get this error "Error: No host specified" how do I correct it
Hi Hans, If I was to incorporate 'Clip Raster by Mask Layer' on the graphical modeler, it only allows me to clip one 'raster' (allows only one input layer) - however, I would like to clip 2 - 3 using the 'same' mask layer. what do you reckon would be the best way to get around this?
You can use the Run as Batch Processing button at the bottom of the dialog. See also docs.qgis.org/3.34/en/docs/user_manual/processing/batch.html
@@HansvanderKwast thanks Hans 🙂 always a pleasure.
ThankYou!
When i download na data result theres no .shp file in the downloaded files. Why?
Prof how are you. I am having a problem with my data......l am trying to create a Covid-19 time series for South Africa....
Thank you sir for the tutorial, does this method also work for sea surface inundation?
Thank you very much. Just a Question, Are there any way to run these queries in the Python Console in QGIS by importing Quick OSM
thanks a tonnnnnnnnnnnnnnn
Hello sir, I need to carry out a flood vulnerability assessment of basin using morphometric analysis using Qgis, can you help? Do you have any videos on such a project? Or a step by step?
Hi! You can check this playlist: kzread.info/head/PLeuKJkIxCDj1bKCAMEE8NLbaNMVT9w3_X or have a look at these tutorials: courses.gisopencourseware.org/course/view.php?id=10 That's all I have on this topic.
Hello Sir PC raster LDD to Grib is not giving the results, it show an error stating that: "unable to convert to grib file with GDAL: Unsupported or missing spatial reference system" the CSR i am using is EPSG:7763-WSG 84/Himachal Pradesh
Maybe thr CRS is not supported by the underlying PDAL library. Try to reproject to UTM first.
@@HansvanderKwast I tried from UTM 43, 44 all other CSR which can be used for this area, and some random other CSR just to check the output. But no success yet. I'll try again tomorrow.
@sharansharma1 Okay. Then there might be an issue with the data. Maybe too big. Hard to tell what goes wrong.
Does the target in the reprojection make a difference? I don't know which UTM target to choose so I just chose Default CRS with the rest of the same parameters for the reprojection. Yours runs so quickly whereas I've been waiting for hours for the projection to finish...any tips?
The target should be the projection you want to work with. If you just want to visualise the DEM, you can keep it in GCS (EPSG:4326) and don't need to reproject. If you want to do analysis, you need to reproject, so the X and Y units are the same as the Z units (m). You can choose a national projection or for example UTM. If you google UTM zones you can find pictures with all the zones and choose the one for your study area. More info about projections: kzread.info/head/PLeuKJkIxCDj1c0ffAkIb5P1-80lporfbU&si=4TgTShYRpmrMyCdH
It has potential. I used it on a 25x25m pixel scan of a geologic map with mixed results. My main issue was a constant "cannot connect with completion server" error message although i was connected to good internet. Could not find any way to solve this.
All good but, It does not generate the CSV file...why would be the reason?
Please provide more details on your problem. Did you get an error message?
@@HansvanderKwast I experienced the same. There is no error message but the CSV file doesn't appear to the location I selected
Hi Hans. I get an error in lddcreate tool: Traceback (most recent call last): File "C:\Users/Zvone/AppData/Roaming/QGIS/QGIS3\profiles\default/python/plugins\pcraster_tools\processing\algorithms\pcraster_lddcreate_algorithm.py", line 169, in processAlgorithm setclone(input_dem.dataProvider().dataSourceUri()) TypeError: Cannot open 'E:/Documents/GIS/Cvitovic/VirtualRaster_DMR.vrt'. Note: only the PCRaster file format is supported as input argument. Can you help please?
The PCRaster Tools can only read the PCRaster file format. Therefore, you need to convert your vrt layer. You can use the tool from this video: kzread.info/dash/bejne/aaKHyo9yY92ZgtI.html
Thank you so much for this video. I was panicking after deleting the browser section. Really appreciate it.
Well, it seems useless for scans of lower quality but still recognizable beyound any doubt by human eye.
Dankjewel!
hello, do you now when the DEM being generated from the plugin was produced?
SRTM is the Space Shuttle Topography Mission, which collected data for the DEM in February 2000.
Anyone knows how to get DTM data of Australia and is that the same as DEM data?
Maybe this site helps: www.ga.gov.au/scientific-topics/national-location-information/digital-elevation-data. DEM stands for Digital Elevation Model, DTM is Digital Terrain Model (terrain elevation without man-made and natural objects) and DSM is Digital Surface Model (terrain + man-made and natural objects), see kzread.info/dash/bejne/oqJ1xsOsoaved84.htmlsi=yNfBfJWpUVwa37jC
Hi, I'm unable to convert junctionid to nominal, as it is raising an exception of crs_wkt. Can you please suggest how to overcome this? Thanks.
The error is for some reason related to your projection. What you can do is to delete the xml file of your input layer, so all projection info is removed. Then run the tool again and assign the correct projection back to the input and created output.
Hi, my SAGA tools still won't show up :( I'm seeing two versions though on my OSGEO4W, version 9.3.1-1 /7.8.2-31 and 7.9.1-1.
Is it different from Fragstats?
Same metrics as far as I know.
Very beneficial, is it possible to just animate only to your region of interest (Clipping)
Yes, you can do one of the following: (1) clip the polygons you need, (2) create a mask with an inverted polygon and zoom in to your area
Polygonize (raster to vector) - makes subcatchments into a shp file to use in civil 3d after final step
Does this still work?
Yes. You can do this with the PCRaster package in Python.