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.

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    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
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    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
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    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

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.

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