Nissa, Vital Force

[+1]: Untap target land you control. Until your next turn, it becomes a 5/5 Elemental creature with haste. It's still a land.
[−3]: Return target permanent card from your graveyard to your hand.
[−6]: You get an emblem with "Whenever a land you control enters, you may draw a card."

Kaladesh Remastered

+1: Untap target land you control. Until your next turn, it becomes a 5/5 Elemental creature with haste. It's still a land.
−3: Return target permanent card from your graveyard to your hand.
−6: You get an emblem with "Whenever a land enters the battlefield under your control, you may draw a card."

Kaladesh Promos

Magic Online Promos

San Diego Comic-Con 2018

A permanent card is an artifact, creature, enchantment, land, or planeswalker card.

After resolving Nissa's first ability, the target land still has any abilities it had before it became a creature and any other types it had.

You can activate Nissa's first ability targeting a land that's already untapped.