One point that is not being sufficiently taken into consideration in the debate about plantations as carbon sinks is the production end of the issue. That is, most of these monocultural non-native species plantations are being grown for either of two products: paper or fiberboard. In both cases, the trees will be turned into chips and then made into something else.
How much of the actual wood fiber grown on the plantation is sequestered? Very little, especially in the case of paper.
Let's see: the trees grow, sucking up a certain amount of carbon as wood fiber mass. Much of the soil around the trees is compacted in the logging process. This does two things: drives out much of the carbon in the organic layer, and makes the soil more prone to erosion, which further frees up the carbon it holds.
Much of the carbon, of course, is turned into leaves which eventually fall to the ground as the tree grows. These leaves rot into the soil, becoming part of that organic layer mentioned above.
The trees are cut and chipped, eventually being turned into pulp and then into paper or cardboard. These products are then used and most often thrown away. In the case of corrugated cardboard, very few countries have achieved recycling rates over 50%. Most of the corrugated in the world is used once and then landfilled.
Even in the US, a country with a relatively high recycling rate (as compared with the rest of the world, not with other industrial countries, that is), only about 14% of white office paper is recycled. Much of the plantations in Brazil and Indonesia, two of the world's leading pulp and paper producers, is going into office paper.
So, this paper --where one would argue that most of the carbon taken up by the plantation has been sequestered-- is pretty much landfilled. Here, the bulk of it will, over time, decompose in an anearobic environment -that is, without the presence of oxygen- and be released into the landfill (and eventually the atmosphere) as methane. Methane is 25 times more effective as a global warming gas than is carbon.
Therefore, most of the sequestered carbon will be ultimately released as methane or simply re-released as carbon in the process of harvest, chipping, pulping, waste, production into paper, and finally, decomposition.
A small portion (that going into fiberboard) will become non-durable wood products which will also soon be landfilled. That is, even fiberboard is disposable over a relatively short period of time (at least in America, where this type of furniture lasts only a few years). And when it is buried in the landfill at the end of its short life, it too, will generate methane.
A tiny fraction of the wood fiber produced by the plantation will be sequestered over the long term as durable wood products, far exceeded, however, by the methane generated by the disposal of all the paper and fiberboard thrown out by an ever-expanding overconsumptive global economic machine.
The science behind carbon sequestration in plantations is not science at all, but is instead smoke and mirrors used to generate more plantations, benefitting large paper, pulp and wood products companies, at the expense of the Earth and local people.
Carbon sink plantation promoters seem to have forgotten that in order to actually sequester the carbon, the trees must either:
- be left to grow; or
- be turned into durable products that will hold that carbon for hundreds of years; and
- never be allowed to decompose in an anaerobic environment.
None of this is happening in any substantial way when it comes to fast-growing non-native plantations.
Source: Tim Keating, Rainforest Relief