catchment vs salt flat

catchment

noun
  • Any structure or land feature which catches and holds water; the collection of such water. 

  • A catchment area, or the people it serves. 

verb
  • To divide into catchment areas. 

salt flat

noun
  • A dry lake or playa whose level bed contains abundant salt. 

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