Carbon Storage Effects Research Articles

Climate change mitigation effect of harvested wood products in regions of Japan.

BackgroundHarvested wood products (HWPs) mitigate climate change through carbon storage, material substitution, and energy substitution. We construct a model to assess the overall climate change mitigation effect (comprising the carbon storage, material substitution, and energy substitution effects) resulting from HWPs in regions of Japan. The model allows for projections to 2050 based on future scenarios relating to the domestic forestry industry, HWP use, and energy use.ResultsUsing the production approach, a nationwide maximum figure of 2.9 MtC year−1 for the HWP carbon storage effect is determined for 2030. The maximum nationwide material substitution effect is 2.9 MtC year−1 in 2050. For the energy substitution effect, a nationwide maximum projection of 4.3 MtC year−1 in 2050 is established, with at least 50 % of this figure derived from east and west Japan, where a large volume of logging residue is generated. For the overall climate change mitigation effect, a nationwide maximum projection of 8.4 MtC year−1 in 2050 is established, equivalent to 2.4 % of Japan’s current carbon dioxide emissions.ConclusionsWhen domestic roundwood production and HWP usage is promoted, an overall climate change mitigation effect is consistently expected to be attributable to HWPs until 2050. A significant factor in obtaining the material substitution effect will be substituting non-wooden buildings with wooden ones. The policy of promoting the use of logging residue will have a significant impact on the energy substitution effect. An important future study is an integrated investigation of the climate change mitigation effect for both HWPs and forests.

The economics of timber and bioenergy production and carbon storage in Scots pine stands

We optimize timber and bioenergy production combined with carbon storage in Scots pine (Pinus sylvestris L.) stands, using an ecological-economic model. Forest growth is specified with a highly detailed process-based growth specification, and optimization is based on an efficient generalized pattern search algorithm. The optimized variables are rotation length, initial stand density, and the number, intensity, timing, and type of thinnings. The carbon pool includes all aboveground biomass (including dead trees) and timber products. The analysis includes the comparison of different carbon subsidy systems. The results are presented for the most relevant site types and thermal zones in Finland. Carbon storage increases the optimal rotation length, number of thinnings, and initial density at all forest sites. Carbon storage effects on stand density and harvests are strongest at poor sites. Timber output increases with carbon price. High natural mortality in our results implies notable carbon storage in dead trees and a positive contribution to biodiversity. The stand-level analysis is extended to a cost-efficient national-level carbon storage plan.

Environmental and Socioeconomic Impacts of Utilizing Waste for Biochar in Rural Areas in Indonesia–A Systems Perspective

Biochar is the product of incomplete combustion (pyrolysis) of organic material. In rural areas, it can be used as a soil amendment to increase soil fertility. Fuel-constrained villagers may however prefer to use biochar briquettes as a higher-value fuel for cooking over applying it to soils. A systems-oriented analysis using life cycle assessment (LCA) and cost benefit analysis (CBA) was conducted to analyze these two alternative uses of biochar, applying the study to a rural village system in Indonesia. The results showed soil amendment for enhanced agricultural production to be the preferential choice with a positive benefit to the baseline scenario of -26 ecopoints (LCA) and -173 USD (CBA) annually pr. household. In this case, the positive effects of carbon sequestration to the soil and the economic value of the increased agricultural production outweighed the negative environmental impacts from biochar production and the related production costs. Use of biochar in briquettes for cooking fuel yielded negative net effects in both the LCA and CBA (85 ecopoints and 176 USD), even when positive health effects from reduced indoor air pollution were included. The main reasons for this are that emissions during biochar production are not compensated by carbon sequestration and that briquette making is labor-intensive. The results emphasize the importance of investigating and documenting the carbon storage effect and the agricultural benefit in biochar production-utilization systems for a sustainable use. Further research focus on efficient production is necessary due to the large environmental impact of biochar production. In addition, biochar should continue to be used in those soils where the agricultural effect is most beneficial.

Carbon footprint including effect of carbon storage for selected wooden facade materials

The outer facade constitutes a substantial volume of the total consumption of materials used in a building and the need for maintenance of the facade makes it especially interesting from a life cycle perspective. The range of wooden materials and products used for facades has different impacts over the life cycle, but the analyses so far have not included a time-adjusted global warming potential (GWP). Wooden facade materials were assessed with respect to their life cycle carbon footprint based on the environmental product declarations (EPD) and adjusted according to EN15804. The results showed low impacts of untreated Scots pine heartwood (≈1 kg CO2-eq. per square meter [m2]), medium for thermally modified Scots pine, coated Norway spruce and oil/copper–organic preservative-treated Scots pine (1–5 kg CO2-eq. per m2) and high for furfurylated Scots pine and acetylated Radiata pine (5–10 kg CO2-eq. per m2). The results with time-adjustment showed that these methods have a potential large effect on the carbon footprint of wooden claddings. The inclusion of biogenic carbon flows and timing seems to be more important than the difference between the product when biogenic carbon is not included. This fact highlights the importance time-adjusted GWP would have for wood products EPDs.

Implications of albedo changes following afforestation on the benefits of forests as carbon sinks

Abstract. Increased carbon storage with afforestation leads to a decrease in atmospheric carbon dioxide concentration and thus decreases radiative forcing and cools the Earth. However, afforestation also changes the reflective properties of the surface vegetation from more reflective pasture to relatively less reflective forest cover. This increase in radiation absorption by the forest constitutes an increase in radiative forcing, with a warming effect. The net effect of decreased albedo and carbon storage on radiative forcing depends on the relative magnitude of these two opposing processes. We used data from an intensively studied site in New Zealand's Central North Island that has long-term, ground-based measurements of albedo over the full short-wave spectrum from a developing Pinus radiata forest. Data from this site were supplemented with satellite-derived albedo estimates from New Zealand pastures. The albedo of a well-established forest was measured as 13 % and pasture albedo as 20 %. We used these data to calculate the direct radiative forcing effect of changing albedo as the forest grew. We calculated the radiative forcing resulting from the removal of carbon from the atmosphere as a decrease in radiative forcing of −104 GJ tC−1 yr−1. We also showed that the observed change in albedo constituted a direct radiative forcing of 2759 GJ ha−1 yr−1. Thus, following afforestation, 26.5 tC ha−1 needs to be stored in a growing forest to balance the increase in radiative forcing resulting from the observed albedo change. Measurements of tree biomass and albedo were used to estimate the net change in radiative forcing as the newly planted forest grew. Albedo and carbon-storage effects were of similar magnitude for the first four to five years after tree planting, but as the stand grew older, the carbon storage effect increasingly dominated. Averaged over the whole length of the rotation, the changes in albedo negated the benefits from increased carbon storage by 17–24 %.

Younger Dryas event recorded by the mirabilite deposition in Huahai lake, Hexi Corridor, NW China

Deposits from the Huahai ancient lake in the Hexi Corridor were dated using conventional and AMS 14C. A 2500a “carbon storage effect” was defined at 9.25 m depth according to the 14C age difference between a plant macrofragment and detrital organic matter from the same layer. The chronology of this strata indicated that the mirabilite layer at the depth of 8.05 m–9.15 m had formed during the Younger Dryas (YD) event. The formation of the mirabilite layer indicated that the mean annual temperature in the Hexi Corridor dropped by 11 C° during the YD event compared with today. The lowest cold event occurred early in the YD, which is consistent with what has been revealed by other high-resolution records, such as those of Arctic ice cores and stalagmites in mid-latitude regions.

Quantitative estimation of carbon removal effects due to wood utilization up to 2050 in Japan: effects from carbon storage and substitution of fossil fuels by harvested wood products

Carbon absorbed by forests remains stored in the timber used for wood products, and a change in wood product stock can be evaluated as substantial removal/emission of atmospheric carbon. Since the carbon storage effect due to harvested wood products (HWP) might be taken into account in the future framework of carbon mitigation, it is crucial to estimate the carbon fl ow and stock concerning HWP for the next commitment period. In the present study, we developed a model for estimating the fl ow and stock of wood products in Japan’s building, furniture, and paper sectors. The HWP carbon storage effect and substitution effect (carbon reduction by substituting fossil fuels and energy-intensive materials with HWP) up to 2050 were quantitatively estimated by lifetime analysis. Our model simulation revealed that (i) the carbon stock change in Japan due to HWP would be evaluated as a large emission if the atmospheric-fl ow approach is adopted, (ii) carbon removal would not significantly increase if the ratio of newly constructed wooden buildings/furniture remains stable, and (iii) the carbon storage effect together with the substitution effect would have a significant impact on climate change mitigation if the ratio of newly constructed wooden buildings/furniture is gradually improved to 70% by 2050.

ライフサイクルＣＯ２評価に基づいた都市公園の整備計画に関する研究

To arrest global warming,it is also expected that the effect of carbon storage and sequestration of urban green spaces will be an important factor. On the other hand,the life cycle CO2 (hereafter, LCCO2) evaluation to reduce CO2 emissions is watched with interest by each sector. Because of this situation, the purpose of this study was to discuss the planning and design of urban Parks based on LCCO2. The study parks estimated in this study were selected 5 block parks in Sapporo City, Hokkaido. The results are follows: 1) It were possible to apply the LCCO2 evaluation method to all study parks. 2) In the study parks under the present conditions, the average amount of LCCO2 per area of 1 hectare of each sample was estimated about 58.4t-C/ha (range:45.9–78.6t-C/ha). 3) In the study park (3 types) changed basing on a landscape planning considered to reduce the amount of LCCO2, the average reduction rate of LCCO2 was estimated about 17.1–42.0%. 4) Therefore, we grasped to be important to discuss landscape planning considered to reduce the amount of LCCO2.

都市公園に対するライフサイクルＣＯ２評価に関する研究

To arrest global warming, it is also expected that the effect of carbon storage and sequestration of urban green spaces will be an important factor. On the other hand, the life cycle CO2 (hereafter, LCCO2) evaluation to reduce CO2 emissions is watched with interest by each sector. Because of this situation, the purpose of this study was to discuss the method of LCCO2 evaluation to urban parks, to apply that method to an actual urban park. The study parks estimated in this study was selected neighborhood park in Sapporo City, Hokkaido. The results are follows: 1) The method of LCCO2 evaluation to urban parks could be constructed, and it was possible to apply the constructed method to the study park. 2) In the study park under the present conditions, the amount of LCCO2 was estimated about 66.5t-C. 3) In the study park changed basing on a landscape planning considered to reduce the amount of LCCO2, the amount of LCCO2 was estimated about 46.1t-C. 4) Therefore, we grasped that it important for landscape planning to discuss reducing the amount of LCCO2.