Prevent Poles getting arable land in Yorkshire town (8)
I believe the answer is:
barnsley
'yorkshire town' is the definition.
(I've seen this before)
'prevent poles getting arable land' is the wordplay.
'prevent' becomes 'bar' (bar can mean to prevent or disallow).
'poles' becomes 'NS' (North and South poles).
'getting' says to put letters next to each other.
'arable land' becomes 'ley' (ley can mean a piece of land for farming).
'bar'+'ns'+'ley'='BARNSLEY'
'in' acts as a link.
(Other definitions for barnsley that I've seen before include "Large South Yorkshire town" , "A South Yorks. town" , "S. Yorks. industrial town" .)