Qwer
I believe there is just too much crap sprayed out there, many websites with food lists and who show no explanation or comprehension.
I believe that the real thing is about mineral balance, and how your food intake influences it beyond the own content in minerals of the food.
H+ ions can bind with hemoglobin, taking the place of oxygen. Many enzymatic complexes have a similar place where H+ can bind, slowing down the enzymes work.
Where the alkaline theory fails is that it proponents don't talk about a balance that much, and too much emphasis is put on calcium, although I don't deny the importance of calcium.
Zinc is very important, and a diet completely devoid of meat will be very low in zinc.
I believe a balanced diet is one of our ancestors, which is, by calories, largely meat, but by volume, mainly veggies, completed with nuts and fruits. Of course, the diet depends on what is available. If the only thing you found that day was a huge walnut tree, chances are you will eat a lot of it. As a side and unrelated note, almonds are not really a food our ancestors ate, since the bitter almonds became the sweeter almonds only "recently".
This is an article which quantify an alkaline diet with PRAL scores, telling that the 200+g of protein rich diet of our ancestors was very alkaline and that a diet high in sweet potatoes would be much more alkaline than the diet of americans.
http://www.ajcn.org/cgi/content/full/78/4/802