Important keywords emerging from all Natura 2000 network (N2K) studies (N = 572) published between 1996 and March 2014.

Keywords in bold have both high degree and high betweenness; degree measures the number of relations that run from a keyword to other keywords; betweenness measures the number of shortest paths that run through a keyword, and identifies keywords that connect other keywords (connectors).Important keywords emerging from all Natura 2000 network (N2K) studies (N = 572) published between 1996 and March 2014.