Quick forward movements onto the plants near the water (8)

I believe the answer is:

onrushes

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'plants near the water' is the definition.
I can't judge whether this defines the answer.

'quick forward movements onto' is the wordplay.
'quick forward' becomes 'on' (I am not sure about the 'quick' bit.).
'movements' becomes 'rushes' (rush is a kind of movement).
'onto' means one lot of letters go next to another.
'on'+'rushes'='ONRUSHES'

'the' is the link.

Can you help me to learn more?

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

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