Worryingly, I just passed 9 logging trucks on the road to the Maliau Basin. In fact, I hear that the trucks have been coming thick and fast along this road for the last 6 months. It’s very difficult to get concrete information on the timings, location and intensity of logging in Sabah (as elsewhere in Malaysia), but this seems to indicate a dramatic rise in the rate of logging around Maliau.
To convert these 9 logging trucks into something tangible, we can carry out a quick back-of-the-envelope calculation into what this might mean for the forests in this area. It goes something like this:
I counted between 12 and 30 logs on each truck: we’ll take a conservative average of around 20 logs per truck. I was observing the road for 2 hours, but I was travelling at around 60 kph for that time. So this is equivalent to sampling ~120 km of road. Given that a logging truck probably does around 50 kph, it would take about 2.4 hours for it to do the same journey. So, if I had remained stationary at the beginning of the road, it would have taken 2 + 2.4 hours to observe all 9 trucks. From this, we have a rough rate of about (9 / 4.4 = ) 2 trucks per hour coming out of the area. Assuming trucks only emerge during a 10-hour working day (which we know to be a fallacy, at least, in other areas), we can therefore say that 20 trucks came out that day, or (20 x 20 =) 400 trees.
Is this a big number? We can take a further leap of faith, using a figure for the number of logs (principally dipterocarp trees) that logging operations usually remove per hectare: around 15 (Curran et al. 1999, Science 286: 2184). This means that the 400 trees we calculated coming out in a single day represented 27 hectares of trashed forest. And this doesn’t include the forest destroyed to access, fell and transport these logs (skid trails, secondary roads, crash sites, logging camps etc). For the forest directly disturbed to access these logs, we can probably add an additional 15% onto our 27 hectares if we are being conservative, so 31 ha. Converting this to the standard SI unit of forest loss, this equates to about 50 football pitches! Obviously we should take this figure with a generous pinch of salt, but we’re probably in the right ball-park.
Maybe it’s just me, but this sounds like a lot of forest. What do you think?
The image of the lumbering logging truck, groaning under the weight of rainforest logs, is so often used that it’s easy to become desensitized to it. Regardless whether this calculation is worth the blog it’s written on, it still serves to remind me what a logging truck really represents.
Written May 2011
UPDATE: Some commentators have linked recent logging rushes (particularly horrific in the northern Ulu Segama area, decimating orangutan populations) with the Sabah Forestry Department’s widely-publicised aim to have all of its Forest Management Units FSC- certified as sustainable by 2014. Now, I would never entertain such thoughts (for one thing, my research permission depends on it), but some quarters have suggested that we could be seeing a last-ditch attempt to pull as many logs out of Sabah before the door is bolted.
The Forest Management Plan for the Maliau Basin is also up for review this year. There is talk of plans to re-log the buffer area. This area was logged as recently as the mid-1990s, giving it just 15-20 years to recover. A second round of logging could put pressure on one of the last remaining herds of Tembadau (a species of wild forest cattle currently assessed as Endangered on the IUCN Red List) in the region, and currently a common sight along the Maliau access road.