Charcoal Production
Last week, I had the opportunity to spend a few days in the field up in Siem Reap with a visiting geographer. He and his students had been working with some satellite imagery– using field observations and image processing software to classify what is growing on the land, and how that land is being used. Comparing images taken at different times is a useful method of tracking land cover changes (e.g. agricultural expansion, deforestation and the like). They had come up with a few areas on the images that did not seem to make sense. So, he was in the field navigating to these sites using a GPS and then visually verifying what was happening on the ground. It was a lot of fun, and I learned a lot.
On of the areas we visited was in the low hills just southwest of Phnom Kulen. The screenshot from Google Earth is below (click on it for a larger image). The red spot marks one of the places where we stopped to look around. Notice how it is placed right in the middle of a patch of forest. Now, Google is not all that clear about when their images are taken (and where they come from). However, they claim that all of them are less than 3 years old.
Now, the following image was taken at that site a couple of days ago. Not a lot of forest cover now, though in some areas there is heavy grassy regrowth. Most all the area around there had been cut over and burned. Some sites had old charcoal kilns, too. Land cover change in action!
It is not all that clear with this size image, but the big tree on the left hand third of the image is some kind of strangler fig. However, its host tree (the stranglee) is missing! Neat! I am not sure if it had been cut down or burnt out. According to the sparsely placed red and white markers, this area may have been a little miney. People had clearly been working all over that landscape, however I am still a little uneasy in those areas. So, I did not explore too far from the road.
As we moved back from this point towards the main road, it was evident that we were moving along a gradient where the land furthest from the access road had been cleared most recently. While, the land closer to the road had been cleared some time ago. Closest to the road, where there was access to water, there were small stands of mangos, Acacia woodlots and even bananas.
There were a few houses along the road– not many. A few had charcoal kilns, or wood stacked to be sold. Quite a few trucks passed us filled with either wood cut into kiln-length logs, or bags of charcoal itself. We bumped into one group of people who was unloading a kiln and filling up grain sacks for shipping. We chatted with them for a few minutes, but they were busy, and understandably not too interested in being interviewed. Though they did tell us that buyers came in from Siem Reap town, and that the charcoal was also sold in town.
That big igloo-looking structure is the kiln. There were two men working to empty it and fill up the bags, though only one is visible here. They are pretty sophisticated structures, with pits dug quite deeply into the ground, and multiple vents which can be plugged or unplugged to control the burn. They looked robust enough to use repeatedly, too. I was impressed. I had seen a little charcoal production while working in Tanzania. There, the kilns were ad-hoc affairs, often built right on the site of the former woodland. The wood was stacked up and earth was piled around it and over it until the kiln was ready. Once the charcoal was finished, the kiln was broken apart and the charcoal removed. The kilns below were just down the road from those folks. Sadly, I do not have any pictures of kilns from Tanzania for comparison.
I have always had a soft spot for charcoal production. It would take quite a bit more than the hour or so we spent in thus area to really get a handle on the production process, the market and how it all fit into the way folks make a living. Maybe next time!
