The two phrases are quite the same, but they have a subtle difference between "领" and "据”。
According to the dictionary,
领:1.) lead, usher; 领导;引领
2.) have jurisdiction over; be in sb.'s possession 占领
据:1.) occupy; seize 盘据, 占据
2.) rely on; depend on 据险固守
占据/占据新的科技领域
占据/占领新市场
占领/占据地盘
It's better to use 占领 because it has jurisdictions over the area.
占据区(X) 占领区(O)
占据军(X) 占领军(O)
Vendors may occupy an area but they cannot have jurisdiction once the police come.
摊贩占据了人行道
Feelings or sunlight can only occupy the spatial/spiritual corners but they don't have jurisdiction either.
天光占据了房间的每个角落
恐惧占据了人们的心灵