Friday, 20 November 2015

Mission complet

So we spent an amazing 10 days or so at the Inselberg field station, Nouragues. The weather was a bit mixed - the so-called dry season seemed to be ending a bit early, and so some days we had to flee from unbelievable rain storms. But working dawn until dusk, and following Andy's new Stakhanovite sampling regime of a 10m grid, with 10 rolling targets - 5 ahead, 5 behind - we completed 242 scans in the 1 ha H20 plot, at a level of detail we've never even got close to before. We were indebted to Blaise (Tymen) who was our 3rd man and guide, and he helped made the task manageable. So far, the data look absolutely stunning. Our first visualisation is here:


The location of the station is stunning - deep in the dense Amazonian jungle. The helicopter ride in and out was worth the trip in its own right, even if it was cloudy on the way in. It wasn't on the way out!



Notes on scanning and lessons learned?
Scanning at this density (4 x what we've done before), ditching the waveform data and the photos, we managed to achieve 40-50 scans per day, even with the odd shower, as opposed to our previous best of 23 previously. We could do this on 2 batteries, and without filling the disk on the scanner so only needing to download in the rapidly fading light of the evening, enabling us to leave the scanner at the plot (in the case in a waterproof bag and under a tarp!).

Doing it this way also meant we only ever needed 10 poles and targets (so you could take 20 say, to leave spares). We just needed to do a little bit of judicious veg shifting & pruning for each new location; we never missed one. Finally, it meant that laying out targets was very, very much quicker and simpler than using the systematic schemes we've used in a 20m spacing in the past. So, swings and roundabouts.

Andy was able to download and register the new data each day, to make sure we could continuously update our chain from the start to the end of the plot. The multi-station adjustment obviously takes exponentially longer as the number of scans grows, but we were able at least to check we could register all scans together.

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