Scientific Reports 7: Article number: 41275; published online: 30 January 2017; updated: 05 April 2017

In the original version of this Article, Affiliation 1 was incomplete. The correct affiliation is listed below.

Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Bei**g 100101, China.

These errors have been corrected in both the HTML and PDF versions of the Article.