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I'm building distribution maps for several species in QGIS but I've been struggling to match the country borders with the lines of the distribution maps.

As you can see in the next picture, both polygons don't match in the coast or in areas with large water bodies and they should, because this species exists everywhere.

The polygons I have are the species distribution (green) and the world map (country borders) in white with a dark grey stroke. What I want to do is match the lines of the species distribution polygon with the world map polygon.

enter image description here

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I could use the snapping tool to make them match but many of the species I'm working with occur in several continents and that would take a long time. For example, just for this small portion you can see how many points I would have to adjust.

enter image description here

Is there a way of doing this in a more automatic way?

Daniel Santos
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    Sorry, from your screenshot and the question in general its not very clear what you have and what you want to achieve: you have a green polygon, a white one (?) and one with black boundaries? Which of these polygons should be snapped to which other one? Can you share your data? – Babel Sep 12 '21 at 10:14
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    Might be the same question as here: https://gis.stackexchange.com/a/384574/88814 – Babel Sep 12 '21 at 10:16
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    Is "Snap geometries to layer" from processing toolbox what you are looking for? – MrXsquared Sep 12 '21 at 10:21
  • @Babel sorry about that and thank you for your answer. I've edited the post to make that more clear. The polygons I have is the species distribution (green) and the world map (country borders) in white with a dark grey stroke. What I want to do is match the lines of the species distribution polygon with the world map polygon.

    I don't think that the aproches on that post would work in my case, because the distribution of the species I'm working with exist only in some parts of Europe and If I would use one of those steps I would get a polygon covering the entire continent. Am I wrong?

     – Daniel Santos Sep 13 '21 at 08:19
  • Just make the buffer small enough not to cover more than you strictly need. And when you clip this buffered polygon afterwards, you get it back where you want. – Babel Sep 13 '21 at 08:22
  • But what about when the distribution of a species ends in the middle of a country? If I create a buffer and then clip it (using the world map layer) won't that distribution limit (in the middle of a country) be wrong? – Daniel Santos Sep 13 '21 at 08:47
  • @MrXsquared that didn't worked perfectly, but I got closer results. In some parts the polygons still do not match but it's closer. Thank you. – Daniel Santos Sep 13 '21 at 08:50

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