Topographical data question

Hi Darren,

How do you tend to go about getting your detailed topographical data for the MapInfo GIS work? Most publicly available DEM data sources I have been able to find are pretty course resolution, and despite my lack of experience, seem too course to provide the level of detail that. There seems to be may different options, all with their pros and cons. Doing a detailed mapping with an RTK GPS system takes a lot of time, and is costly equipment wise. I expect that some farmers that use these systems could provide a bunch of data from running over the farm for many years, albeit generally limited to cropping scenarios.

Do you use a LIDAR flyover for acquiring data or is this too costly for your clients (all with different budgets of course)? It looks like a lot more LIDAR data sets are becoming available from government agencies, and there is generally a push to unify different agency data sets and improve the spatial resolution.

I am just starting to skill up in GIS and not sure of the practicalities of data acquisition for keyline design.

Cheers,

Elliot

G'day Elliot,

LIDAR is definitely becoming more available and is the technology that will probably become the most mainstream and it can't come early enough. I dream that in the next 5-10 years that the world's ag lands will be LIDAR'd (or otherwise) and that GoogleEarth will have this data there ready to go for this and the next (re) generation of regenerative agriculture designers.

For now though we mainly use RTK GPS that is either generated from 'precision farming' devices or from company's such as FarmingIT (http://www.farmingit.com.au/) here in Australia who survey using a quad-bike mounted kit and traverse a landscape giving us a detailed topo for $8/ha or $3.50/acre which is pretty bloody reasonable given that total station surveys used to cost me 10-15 times this!

If your clients (and you!) value water then they need to be in control of it and 'Landshape' is second behind 'Climate' in the 'Keyline Scale of Permanence' as it is in our 'Regen10' in which we've replaced Landshape with 'Geography'. To control water you need an effective and accurate topo map and we've proven that this is possible using techniques such as 'Making contours on the cheap' (http://permaculturenews.org/2008/09/11/making-contour-maps-on-the-cheap/)and now with tech such as the FarmingIT quad...Broader scale LIDAR use by agencies and the open-source sharing of this data only completes the picture...

Thanks and all the best,

Darren