I remember looking up plant based milk alternatives and being surprised how well almond milk does in environmental impact. I think it was battling oats and soy, and depending on the source, the first/second/third place were changing. Iirc the explanation was that you actually need really little almonds to make a liter of almond milk.

Rice, coconut, cashew etc all had a worse environmental impact, but of course, everything was better than cow’s milk.

(Mind you, it might have been that I used a German source for that, I’m going to try to look it up again.)