Friday, 31 October 2014

School by the river

We had a great morning visiting the local (only) school, St Sebastian. Lucy has been building links between the school and her local school in Edinburgh, to help both sets of kids appreciate what life is like for each other. I'm not sure which is more difficult: for Scottish children to imagine what life is like living beside a huge river in the middle of a humid tropical jungle, where the temperature never drops below mid-20s (if that), snow might as well be from the moon and where the school run involves an intermittently running boat; or for the Brazilian children to imagine having to put on a coat to go out, for days to get dark at 3pm (or earlier!) and for the biggest threat to their lives to be traffic and crossing the road.
Everyone standing still waiting to be scanned, whilst being bitten by ants.
Lucy brought school uniforms from Edinburgh, loom bands (of course!) as friendship gifts, and a met station so the children can record weather data to compare with Scotland. They showed us their work and their school garden - their teacher Cleyson, is showing them how to grow manioc, banana, sugar cane and pineapple without needing to burn and clear forest first. Fire is the primary land clearance method at the moment, with all the attendant risk and long-term damage that it brings.
Snow? What's snow?

We got everyone out, including the school dog, and scanned them. Once again, everyone loves seeing the view the lidar provides! I'd love to come back and see how they're getting on & I really admire what both Cleyson and Lucy are doing here.

Everyone looks more real in lidar world.

Thursday, 30 October 2014

The plots thicken

So we're now a week in to the trip, with 5 full days of scanning we've done all of the drought plot and half the control plot. The second plot is much harder to work in so we've had to improvise, using hand-made wooden tripods for some of the targets - maybe 3m tall. And just moving the scanner and tripod through the understory takes some doing at times. I find myself swearing to no one in particular a fair amount as the tripod snags on another liana, or I bark my knuckles on something for the twelfth time, all the while literally dripping with sweat. I've never sweated this profusely except in a sauna. But with 3 people on the target shake and bake, and me on the lidar, we're moving much faster than we thought: 13 locations today - 26 scans in all - which is our all-time record I think.

I went swimming before dawn yesterday, to do some filming of the sunrise for the ESA online course I'm contributing to. I took the camera they leant me down to the water and saw a herd of these on my way.

Little red rodent

A dawn swim is a thing of beauty in a place like this. This is a screengrab from a 30 minute sequence where I left the camera running as I swam, while the sun came up.

Sun rise over the river at Caxiuana.
Tomorrow, Lucy is taking us to a local school, where she is working with the teacher who organises the kids, the curriculum, the travel, everything. She's paired the school with a school local to her in Edinburgh, so the children in each can get an idea of what life is like across the world. What a great thing to do. I'm going to go along and scan the kids with the lidar, and send them a laminated print of themselves. Hopefully we can do the same for the kids in Edinburgh too.

Wednesday, 29 October 2014

Amazon scanning II

So far so good. We've been scanning for four days and have managed to capture the whole of the drought plot, plus 1/6th of the control plot. This is a major achievement I'd say - 72 scans, from 36 locations in the drought plot. 130GB of data, comprising around 700 million points, and 360 photos. This is an unprecedented dataset from this sort of forest, and we're all really excited to see what it brings in the way of science.
The scanner in action next to one of the runnels in the drought plot.
We've got things working fairly smoothly, operating two teams - one person manning the scanner, and then 3 people moving and placing the reflecting targets in a grid pattern. This can get complicated, and is the key to making sure we can register all the scans together. Lucy has taken charge of this aspect as it needs one person to have an overview of the process - it can get so confusing, particularly late in the afternoon when everyone's overheating and really tired. It's easy to make mistakes which can cost time and good data. Ed has arrived (after an epic 3 day journey!) and is now working with Lucy and Andy to place the targets. This is a much harder job in the control plot, where the understory is so much denser - unsurprisingly, having not been dried out for 10 years. But we seem to have got a system fairly smoothly. We were very lucky to be able to get the workmen to knock up some makeshift tripods for us to raise the targets to 3 or 4m, making them much more visible above the understory. We scanned 6 locations in 3 hours this afternoon. A couple more good days like that and barring any technical mishaps and we'll have cracked it. Oh, and Andy's laptops have both recovered, so he's a very relieved man.
Panorama of the drought plot - panels removed, but runnels still in place.
The scale of the operation to remove and replace the panels is pretty impressive. The local workmen are now replacing the panels since we've finished scanning the drought plot, and now we move on to the control plot. Days are long, hot and very very humid - every pore is dripping after a couple of hours, and it becomes an effort to drag yourself up and down after a while. But the thought of this is pretty enticing after a long day .....
Not a bad way to end a day. Or start one for that matter.

Sunday, 26 October 2014

Up the Amazon

Amazing sunset from the boat as we make our way to the field station at Caxiuana.
We have been very fortunate to be invited to participate in a long-running drought experiment at Caxiuana, Para State, Brazil. The experiment is to establish what happens to the trees in the Amazon when they experience a severe drought. This has happened twice recently,with so-called 1 in a 100 year drought events occurring in 2005 and 2010. These resulted in large-scale mortality or trees and loss of carbon. But many questions remain about resilience, rates of loss and recovery and these are hugely important to understand what will happen to the Amazon under predicted increases in drought frequency and severity.

A view of some large Amazonian trees in the drought plot.
A major difficulty is quantifying the relatively subtle changes in structure that are hypothesised to occur in the upper canopy, not just the loss of large trees (or even small ones). So we are collaborating with Patrick Meir, Ed Mitchard and Lucy Rowland from the University of Edinburgh, along with their Brazilian colleagues at the Museo Goeldi in Brevez, to scan the drought plot at Caxiuana. The 1 hectare plot has had 50% rainfall exclusion for over a decade, making it one of the most droughted pieces of forest in the world. The neighbouring 1 ha plot has been set up as a control, to allow a direct comparison and assessment of the impact of drought.

We arrived this week to scan the two plots, aiming to explore the impact of drought on the canopy in terms of its strcutre, biomass and then differences in the upper canopy. The journey in and the field station and site are spectactular - 500 km by boar up-river to a beatiful, incredibly remote location. We have spent 3 days so far and have scanned nearly all of the drought plot. A few hiccups along the way, including two laptops that have expired due to the humid air, we think. We've managed to revive them with judicious drying and cooling, but we've been warned - the tropics kill electronic stuff. No kidding!