Those payment vouchers are not part of the taxes you owe for 2016 but are for estimated taxes owed for 2017 (and are not mandatory).
Those are estimated payment vouchers for 2017 income taxes. Basically, the government is asking you to pay 1/4 of your 2017 estimated amount owed to avoid any possible penalties/interest. If you believe you will not have an amount due for taxes when you file your 2017 tax return, then you can just ignore those.
For more information on whether or not you need to make those estimated payments, you can review the FAQ below: