Steem - Who maintains the blockchain? I did some reading on the Steem currency, and as i understand it there is no mining of Steem. New coins are created automatically and distributed to the social media contributors.. 

What i don't understand is who's maintaining the public ledger (the blockchain)? In Bitcoin, miners get new bitcoins as a reward for mining, and maintaining the public ledger by verifying transactions. So if there are no miners in Steem, who is varifying the transactions on the ledger?
The Steem blockchain is verified by witnesses.

From the Steemit faq: The Steem blockchain requires a set of people to create blocks and uses a consensus mechanism called delegated proof of stake, or DPOS. The community elects 'witnesses' to act as the network's block producers and governance body. There are 20 full-time witnesses, producing a block every 63-second round. A 21st position is shared by the backup witnesses, who are scheduled proportionally to the amount of stake-weighted community approval they have. Witnesses are compensated with Steem Power for each block they create.

Each Steemit account can vote for up to 30 witnesses.