Question: How long is the term for moderator? Is it one year?

Answer: 
There is no specific term - it is until a moderator steps down or is removed.

[Should Community Moderators be "elected for life", or have terms?](https://meta.stackexchange.com/questions/984/should-community-moderators-be-elected-for-life-or-have-terms)
There are no "terms" for moderators. Instead, they retain their position mostly indefinitely. This is subject to challenge if, say, the moderator wishes to step down (such as if they never had the time for it) or if things go south. Otherwise, they stick around all the time.