For Nikola v8, this plugin has been replaced by
This plugin changes the previous/next links below the posts to reflect the section index instead of the global index. This way, the sections of a blog behave more like independent subblogs.
There is no configuration needed, but i recommend to replace the blog index by a static page to avoid confusing readers. This can be archived by setting INDEX_PATH to some subdirectory, adding pages output to the root directory
PAGES = ( ("pages/*.md", "", "story.tmpl"), )
and creating a corresponding pages/index.md file.
Depends on taxonomies introduced in Nikola 7.8.2 so be sure to use a recent version.