Answer:
First of all let me answer what is a reserve. A reserve is either set aside time or money for a "rainy day". There are two main types of reserve contingency and management reserve. You get your contingency reserve from analysing what can go wrong and if it dose how much time or money you may need. As a project manager you have authority on those funds.
Management reserve is money set a side by senior management for the project in case something goes wrong that the project simply could not make plans for e.g. natural disasters. The project manager dose not have authority over these funds and have to request it from management.
Differences
Contingency reserve .............................. Management Reserve
===============............................. ===============
for risk you can plan for .........................For Events no one can predict
Controlled by project Manager.............. Controller by Senior management
These topic and more are covered in PMP and CAPM training from
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