What is the fine-grained topic of the following text: As a reaction to the nuclear disaster in Fukushima, Japan, starting on March 11, 2011, German Chancellor Angela Merkel's governing coalition shut down roughly 40 percent of the country's nuclear generating capacity in mid-March 2011 and roughly re-implemented the original nuclear phase-out set forth under Chancellor Schroeder’s Social-Democrat/Green government. Only return the topic.
Germany's shutdown and phase-out of nuclear power following the Fukushima disaster