Potential contributions of forestry and wood use to climate change mitigation in Japan
J For Res
Potential contributions of forestry and wood use to climate change mitigation in Japan
Mitsuo Matsumoto 0 1 2 3 4
Hiroyasu Oka 0 1 2 3 4
Yasushi Mitsuda 0 1 2 3 4
Shoji Hashimoto 0 1 2 3 4
Chihiro Kayo 0 1 2 3 4
Yuko Tsunetsugu 0 1 2 3 4
Mario Tonosaki 0 1 2 3 4
0 Forestry and Forest Products Research Institute , Matsunosato, Tsukuba, Ibaraki 305-8687 , Japan
1 & Mitsuo Matsumoto
2 Climate Change - Mitigation, Impacts and Adaptation in the Forestry Sector
3 Graduate School of Agriculture, Tokyo University of Agriculture and Technology , 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509 , Japan
4 Faculty of Agriculture, University of Miyazaki , 1-1 Gakuen Kibanadai-Nishi, Miyazaki 889-2192 , Japan
By considering trade-offs and complementarity between carbon removal from the atmosphere by forests and emission reduction by wood use, we developed a forest-sector carbon integrated model for Japan. We discuss mitigation measures for Japan based on model projections. The integrated model included the forest model and the wood use model. Based on three scenarios (baseline, moderate increase, and rapid increase) of harvesting and wood use, the integrated model projected mitigation effects including carbon removal by forests and emission reduction through the wider use of wood, until 2050. Results indicate that forests will not become a source of net carbon emissions under the three scenarios considered. The baseline scenario is most effective for mitigating climate change, for most periods. However, the sum total of carbon removal in forests and carbon emission reductions by wood use under the rapid increase scenario exceeded the one of the moderate increase scenario after 2043. This was because of strong mitigation activities: promoting replanting, using new high-yield varieties, and wood use. The results also indicated that increases in emission reduction due to greater wood use compensated for 67.9 % of the decrease of carbon removal in 2050, for the rapid increase scenario. The results show that carbon removal in forests is most important in the short term because of the relative youth of the planted forests in Japan, and that mitigation effects by material and energy substitution may become greater over the longer term.
Carbon removal; Emission reductions; Forest sector; Integrated model; Model projection
Introduction
According to the Fifth Assessment Report of the
Intergovernmental Panel on Climate Change
(IPCC 2013)
, it is
extremely likely that human activities have been the
dominant causes of the warming observed since the
mid20th century, and that limiting climate change will require
substantial and sustained reductions of greenhouse gas
emissions. Thus, actions for mitigating climate change are
required in the forestry sector as well. There are two
different approaches to mitigating climate change in the
forestry sector. One is to increase carbon removal from the
atmosphere by forests, and the other is to reduce emissions
through the use of wood. The two approaches exhibit a
trade-off relationship
(e.g., Dufreˆne et al. 2005; Lecocq
et al. 2011; Seidl et al. 2007)
. For example, avoiding
harvesting may increase carbon removal by forests, but may
result in increased emissions because of reduced wood
usage and substitution by fossil fuels. The IPCC’s Fourth
Assessment Report (2007) indicates that the design of a
forest sector’s mitigation portfolio should consider the
trade-offs between the two approaches. On the other hand,
Bellassen and Luyssaert (2014) discuss a complementary
relationship between carbon removal in forests and the
reduction of emissions through the wider use of wood, and
show that the future trajectory of the carbon sink varies
according to the state of sequestration and maturity of
forests. Due to such tight trade-off and complementarity
relationships, the overall potential of the forest sector to
mitigate carbon emissions needs to be evaluated.
Climate change gradually progresses over several
decades, and forests are managed in rotations of at least
several decades. Therefore, the impacts of climate change and
measures to counteract them in the forest sector should be
developed on a long-term basis, ranging from several
decades to more than one century. Projections are also
required to assess the mitigation effects of scenarios in the
forest sector. Moreover, this will allow backcasting to set
future goals and examine which scenario should be
followed to achieve these goals. Therefore, to examine the
various possible scenarios in the forest sector, it is
necessary to compare their effects on the basis of long-term
projections.
Kallio et al. (2013)
examined the trade-off between
sequestered carbon in forests and the substitution of wood
for fossil fuels in Finland. They simulated carbon balances
from 2012 to 2035 and concluded that renewable energy
targets of the EU were excessive and harmful to the
climate.
Perez-Garcia et al. (2005)
concluded after life cycle
assessment t (...truncated)