Geographics And Perfectmatch.com How Should I Protect My 600+ Collection Of National Geographics?

How should I protect my 600+ collection of National Geographics? - geographics and perfectmatch.com

I National Geographics dating back to 1956 and now when I did my grandfather. Once I had finished reading (yes, I plan), what should I do to protect them? Is there a kind of "best" wood for the library? Anything else?