Care about some land (4)
I believe the answer is:
acre
'some land' is the definition.
(unit of land)
'care about' is the wordplay.
'about' is an anagram indicator.
'care' with letters rearranged gives 'ACRE'.
(Other definitions for acre that I've seen before include "Area measure - Israeli port - Brazilian state" , "Unit of land area" , "Not a lot of land" , "Imperial land measurement" , "A state of W Brazil" .)