The preposition à partir de means from (on) and is in some regard similar to depuis and dès. However, the difference is that depuis and dès describe only relation of time. A partir de can also be used spatial and figuratively.
à partir de =from
time
Le restaurant sera ouvert à partir de huit heures.
The restaurant will be opened from eight o'clock.
figurative
A
partir de cinq mille euros, on
peut trouver de tout.
From 5000 Euros on, one can find everything.
spatial
A
partir de trois mille mètres,
on a du mal à respirer.
From (a height of) three thousand meters it is hard to breathe.
