forest, nature, wilderness, wildlife
This land is protected as a wildlife preserve.

game, hunting

in a/the preserve
She decided to go for a walk in the forest preserve.

carefully, faithfully, lovingly
She carefully preserved all his letters.

perfectly
The style of the original film is preserved perfectly.

seek to, try to
be anxious to, want to, wish to
We were anxious to preserve the original character of the house.

help (to)
We need to take action to help preserve fish stocks.

fight to
campaigners fighting to preserve a historic building

be designed to, be intended to
The Act contained provisions designed to preserve the status quo.

be important to

as
The prison is preserved as a tourist attraction.

for
The collection has been sold to the British Museum where it will be preserved for the nation.

from
an attempt to preserve the corpse from decomposition

an attempt to preserve sth
beautifully, exquisitely, well, wonderfully, etc. preserved
They were thrilled to discover a beautifully preserved specimen of Roman pottery.

be preserved intact
The bones had all been preserved intact.

be worth preserving
You need to say why the building is worth preserving.

poorly preserved
The iron coins are poorly preserved and have rusted.

Preserve is used with these nouns as the object:
anonymity, appearance, autonomy, balance, beauty, character, confidentiality, countryside, culture, custom, dignity, diversity, environment, essence, freedom, habitat, harmony, heritage, honour, identity, illusion, impartiality, independence, institution, integrity, landscape, legacy, liberty, link, memory, modesty, monopoly, monument, neutrality, order, peace, prerogative, privacy, purity, rating, relic, remains, republic, reputation, right, sanity, semblance, skeleton, stability, status quo, tradition, unity, value, viability, wilderness, wildlife