desertification vs logging

desertification

noun
  • The process by which a geographic region becomes a desert, resulting from natural changes in climate or by human activity. 

logging

noun
  • An act or instance of logging (cutting trees). 

  • An act or instance of logging (making an entry in a log). 

How often have the words desertification and logging occurred in a corpus of books? (source: Google Ngram Viewer )