Last year I had the experience of driving along the east coast of South Africa north of Durban. For most of the journey, the surrounding land had rather scrubby vegetation: widely-spaced bushes.
But there was a dramatic change as this was replaced by rows of eucalyptus trees stretching for several kilometers along both sides of the highway. This building of a forest where there was previously none is a good example of creating a carbon sink. This led me to contemplate the pros and cons of plantation forestry.
Earlier this year there was news coverage of two forest-related situations on two other continents. In August the focus was on forest fires in Brazil, caused by land speculators hoping to sell cleared land for raising cattle and grain. In September the focus was on Indonesian forest fires caused by land-clearing for palm oil plantations. These fires destroyed carbon stocks, releasing millions of tonnes of CO2 into the atmosphere, and also produced clouds of smoke that were a health hazard to nearby inhabitants. Both these cases of replacing natural forests with agricultural land are classified as land use change, which is the most common cause of deforestation as the world’s population continues to grow and more food is required. Besides this one-time release of carbon, comparing the carbon footprint of different agricultural uses requires a lot more analysis. Raising beef, for instance, consumes grain crops that use fertilizer, and the cattle also emit methane during digestion of their food.
Creating tree plantations for the purpose of using their wood supply is a positive step in terms of carbon stocks, since establishment of plantations stores carbon permanently, which planting annual crops does not do. In addition, some of the wood from plantations may go into solid wood products with a long lifetime, resulting in further carbon storage. Furthermore, plantations are highly efficient for wood production, due to fast-growing species and easy forest management, and thus have economic and social benefits (jobs). The biggest negative of plantations is that they are generally less biodiverse than natural forests in terms of plant species and animal habitat, but this is even more true for cultivation of annual crops.
The establishment of plantations around the world, such as eucalyptus in South Africa, radiata pine in New Zealand, loblolly pine in the US, and many other examples, can also preserve natural forests, as it takes pressure off harvesting them for wood supply. According to the Forest Stewardship Council, while only 7% of the world’s forests are plantations, they provide 33% of the world’s forest products.
While conversion of old‐growth tropical forest to oil palm plantations initially releases a substantial amount of carbon, oil palm tree cultivation is one of the most productive sources of bio-oil known, at about 6000 litres per hectare, compared to 1200 for canola and 450 for soybeans. The switch from other vegetable oils to palm oil has been driven by the desire to eliminate trans fats, plus the fact that it is a lower cost source of vegetable oil than its competitors. In Europe it is even being used as a bio-oil for energy, replacing fossils fuels, which is good for sustainability, but this needs to be weighed against allegations of labour and human rights abuses on some plantations. The Roundtable on Sustainable Palm Oil (RSPO) was established in 2004 to try and set some global standards for better production and use of palm oil.
One unfortunate consequence of global warming is that natural forests around the world are more subject to forest fires, as witnessed recently in Canada and Australia, for example. This is the result of several factors, including longer fire seasons, drier conditions, insect infestations and increased lightning. Often these forests are in remote areas without road access, and it is difficult to prevent fires from spreading. Tree plantations may not have the same “natural beauty” of natural forests, but the health of the trees can be monitored and managed much more easily.
In a special report by the IPCC in August, it was stated that “reducing deforestation and forest degradation rates represents one of the most effective and robust options for climate change mitigation, with large mitigation benefits globally”. Tree plantations certainly play a part in this mitigation effort, as long as they are well-managed.
Martin Fairbank has worked in the forest products industry for 31 years,
including many years for a pulp and paper producer and two years with
Natural Resources Canada. With a Ph.D. in chemistry and experience in
process improvement, product development, energy management and lean
manufacturing, Martin currently works as an independent consultant,
based in Montreal. He is also an author, having recently published
Resolute Roots, a history of Resolute Forest Products and its
predecessors over the last 200 years.
Martin Fairbank Consulting
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