Funding for this research was provided by:
korea forest promotion institute (2017037A00-1919-BA01)
Article History
Received: 25 June 2019
Accepted: 31 October 2019
First Online: 21 November 2019
Ethics approval and consent to participate
: Not applicable because the research did not involve human participants.
: Not applicable.
: The authors declare that they have no competing interests.