[Qgis-user] Interpolation

[Michael.Dodd]

Any suggestions as to the best way to survey and interpolate ridge and furrow grassland that is not on a flat plane?
I have tried various methods without success.

The ridge and furrow area that I want to map is about 120mx120m, the ridge and furrow pattern is distinct with about 0.5m or difference between ridge ht and furrow base but the pattern has a slight curve towards one end and the land is not flat.  If you are not sure what ridge and furrow looks like then there is an example at 51.9827, -0.9135, the stripes are clearly visible on the google earth image.

Mapping can be done with cm level dgps but does this require many tens of thousands of points to be recorded. Or can fewer points be recorded and qgis interpolation somehow be told to interpolate along the ridge and furrow then fill in the area between them with some sort of curve. The actual curve is also problematic as the ridge top tends to be flattened and not a smooth sine wave.  I don't have good LIDAR of the area but even that resolution may not be good enough.

-- The Open University is incorporated by Royal Charter (RC 000391), an exempt charity in England & Wales and a charity registered in Scotland (SC 038302). The Open University is authorised and regulated by the Financial Conduct Authority.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/20140918/6e8212d9/attachment.html>