2

I´ve got a quite specific question and hope someone understand what I want.

I´ve got two datasets (point-shapes):

  1. Camera traps which gained data of roe deer on forest meadows
  2. Camera traps which gained data of lynx (each camera trap counts given lynx event)

What I did: I loaded both point-shapes in QGIS. Both point-shapes are overlapping each other. I created a heatmap based on lynx events enter image description hereenter image description here

blue rhombus symbolize camera traps on meadows; heatmap symbolize the redder the more lynx-events were counted

What I want: I want values of the heatmap (perhaps the center, camera traps where many lynx were present has a value of 10 and camera traps which had no lynx present has a value of 0), so I can question the roe deer camera traps which lynx-value they have.

6
  • 2
    Welcome to GIS SE. Which tool are you using in QGIS? Can you add a screenshot to verify. – whyzar Oct 29 '20 at 15:11
  • 1
    Could you symbolize the camera locations where the size of the dot represents the # of animals seen - bigger is more, smaller is less, and if you did that for both camera trap layers, each would have a different colour? – DPSSpatial_BoycottingGISSE Oct 29 '20 at 15:46
  • @DPSSpatial I did the dot size which get bigger the more lynx events were counted, but the meadows-cameras has a different data table, where the value of lynx presence only should be added – Linda Oct 31 '20 at 15:44
  • @whyzar I now added the screenshots of the tool I used – Linda Oct 31 '20 at 15:45
  • 1
    Interesting, but I'm not sure what you are trying to accomplish with this map. I think that you want to display some sort of spatial relationship between lynx and deer. Am I correct? It also appears that the points for both layers represent camera locations (NOT animal locations), and each point contains a count of the lynx and deer photographed from that location. If I am correct, how do you model the areas not seen by the cameras? Also, did a lynx camera ever photograph a deer, and vice versa? Perhaps you could edit your OP to include a hand-drawn example of what you would like to show. – Stu Smith Oct 31 '20 at 16:30
1

I just found out myself which tools I have to use:

First: I used the wrong heatmap tool. Not the heatmap configurator which can be find in the symbol layer of the shape, but the tool "interpolation - heatmap". Here is how it looks like: enter image description here This heatmap tool generates raster data with values. In my case I used the the lynx-camera trap layer and weighted it with the lynx event attribute.

Second: I installed a plugin called "point sampling tool" which looks like this: enter image description here With this tool I can choose my meadow-camera traps which contains my sampling points and the generated raster data of the lynx-camera traps where I want to get the values from for my sampling points. Running this tool generates a geo-package layer with the meadow sampling points and assigned values of the raster.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.