Runs o’er so fresh coastal lands (10)

I believe the answer is:

foreshores

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'coastal lands' is the definition.
The answer and definition can be both natural objects as well as being plural nouns.
Maybe they are linked in a way I don't understand?

'runs o'er so fresh' is the wordplay.
'runs' is an anagram indicator.
'oer'+'so'+'fresh'='oersofresh'
'oersofresh' is an anagram of 'FORESHORES'.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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