Several forest mitigation options exist: afforestation/reforestation, Deforestation and forest degradation, forest management for carbon stocks and wood products. The IPCC notes that when properly designed and implemented, these forestry mitigation optiosn should provide substantial co-benefits in terms of employment and income generation opportunities, biodiversity and watershed conservation, provision of timber and fibre as well as aestethic and recreational services (IPCC, 2007).
While reducing emissions from deforestation and forest degradation in developing countries, inlcuding conservation, sustainabble management of forests and enhancement of forest carbon sinks (Called REDD+) currently is not the primary driver of forest management options (i.e. the other benefits of forest management are the primary driver instead of the emission reductions), the United States Environmental Protection Agency (2005) notes that future changes in carbon valuation could result in large increases in the use of REDD+ as the primary driver. This is reflected in the international negotiations on climate change in Cancún as REDD+ is incorporated into the Cancún Agreements. The technique of forest management is an important aspect in global climate change mitigation efforts. The image above shows the effect of a difference in forest management as it shows the border between two countries with two different management plans. The video below outlines a project to address deforestation.
Afforestation and reforestation are defined as: "the direct human-induced conversion of non-forest to forest land through planting, seeding, and/or the human-induced promotion of natural seed sources" (IPCC, 2007). The two terms are distinguished by how long the nonforest condition has prevailed. For the remainder of this description afforestation is used to imply either afforestation or reforestation.
Deforestation is defined as: "human-induced conversion of forest to nonforest land uses"(IPCC, 2007). Deforestation is typically associated with large immediate reductions in forest carbon stock, through land clearing. Forest degradation - reduction in forest biomass through nonsustainable harvest or land-use practices - can also result in substantial reductions of forest carbon stocks from selective logging, fire and other anthropogenic disturbances, and fuelwood collection (Asner et al., 2005).
Forest management are defined as: "activities to increase stand-level forest carbon stocks" (IPCC, 2007). Such activities include harvest systems that maintain partial forest cover, minimize losses of dead organic matter (including slash) or soil carbon by reducing soil erosion, and by avoiding slash burning and other high-emission activities.
Wood products derived from sustainably managed forests address the issue of saturation of forest carbon stocks. The annual harvest can be set equal to or below the annual forest increment, thus allowing forest carbon stocks to be maintained or to increase while providing an annual carbon flow to meet society’s needs of fibre, timber and energy. The duration of carbon storage in wood products ranges from days (biofuels) to centuries (e.g., houses and furniture). When used to displace fossil fuels, woodfuels can provide sustained carbon benefits, and constitute a large mitigation option.
The Food and Agriculture Organization (FAO) of the United Nations estimates global forest cover to be just over four billion hectares, which corresponds to about 31 percent of total land area (FAO, 2010). Furthermore, the FAO determined that while deforestation rates show signs of decreasing, they are still "alarmingly high" (FAO, 2010). Figure 1 illustrates the deforestation around the world's regions. [media:image:1]
A more detailed view of the world's forests is illustrated in Figure 2. [media:image:2]
Around 13 million hectares of forest are converted to other uses or lost through natural causes annually throughout the past decade. Brazil and Indonesia have managed to significantly reduce their rate of loss (FAO, 2010). Figure 2 illustrates the dynamics of deforestation. Deforestation is mainly the result of converting forests to agricultural land. However, expansion of settlements, infrastructure and unsustainable logging practices also cause deforestation (MEA, 2005).[media:image:3]
The world's forest store a vast amount of carbon which is estimated to be around 289 gigatonnes (Gt) of carbon in their biomass alone (FAO, 2010). Due to deforestation and poor forest management, carbon stocks in forest biomass for the world as a whole decreased by an estimated 0.5 Gt annually during 2005-2010 (FAO, 2010). Therefore, the technique of forest management is an important aspect in global climate change mitigation efforts.
Several tools have been developed in the context of sustainable forest management, including criteria and indicators, national forest programmes, model forests and certification schemes. These tools can also support and provide sound grounds for mitigation of climate change and thus carbon sequestration. Proper management plans are seen as prerequisites for the development of management strategies that can also include carbon-related objectives (IPCC, 2007).
Forest sector management options for mitiagtion should consider the trade-offs between increasing forest ecosystem carbon stocks and other forest functions and increasing the sustainable rate of harvest and transfer of carbon to meet human needs (IPCC, 2007). Interactions between the forest sector and other use sectors complicate forest sector management options for mitigation. The IPCC outlines the objective of forest mitigation stratiegies as follows: "minimze net greenhouse gas emissions throughout the forest sector and other sectors affected by these mitigation activities" (IPCC, 2007) [emphasis added]. Figure 4 shows the interactions among the different sectors and the forest management sector.
The interactions illustrated in Figure 4 show that activities performed in one sector influence that sector and other sectors. For example, halting all forest harvest for wood would increase forest carbon stocks as the harvesting pressure on forests is removed. However, it would reduce the amount of timber and fibre available to meet societal needs. As a result, other materials such as concrete and steel would be required. Since these products require more energy to produce, the increased demand for these products results in higher greenhouse gas emissions (Gustavsson et al., 2006).
Four different management categories
Like the IPCC report, this description differentiates the management options into four different management categories. These categories are:
1) Maintaining or increasing forest area through reducing deforestation and degradation.
2) Maintaining or increasing forest area: afforestation/reforestation
3) Forest management to increase stand- and landscape-level carbon density
and 4) Increasing off-site carbon stocks in wood products and enhancing product and fuel substitution
Maintaining or increasing forest area through reducing deforestation and degradation.
Deforestation - defined as human-induced conversion of forest to nonforest land uses -leads to large and immediate reductions in forest stock through land clearing. Degradation of forests is the reduction in forest biomass through the non-sustainable use or harvest of forests which can also lead to the substantial reduction in forest carbon stocks from selective logging, fire and other anthropogenic disturbances, and fuelwood collection (Asner et al., 2005). Soares- FIlho et al., (2006) outline that deforestation and degradation can be delayed through the protection of forests. However, while complete protection of forest from all harvest typically results in maintained or increased forest carbon stocks it does exclude the wood and land supply to meet other societal needs. Other management policies such as sustainable forest management or by providing economic return from non-timber products and forest uses which do not involve tree removal, such as for instance eco-tourism (IPCC, 2007).
The largest and most immediate carbon stock impact on the short term can be derived from reduced deforestation and degradaton (IPCC, 2007). This is because large carbon stocks are not emitted when deforestation is prevented.
Maintaining or increasing forest area: afforestation/reforestation
Afforestation and reforestation are defined as: "the direct human-induced conversion of non-forest to forest land through planting, seeding, and/or the human-induced promotion of natural seed sources."(IPCC, 2007). Differentiation into the two terms is determined by how long the non-forest condition of the land has prevailed. While carbon sequestration has been rarely the primary driver of afforestation, future changes in carbon valuation could result in large increases in the rates of afforestation (US EPA, 2005) Carbon valuation can occur in a variety of ways, one of which is increased inclusion of forest carbon sinks into emission trading schemes.
Planting, seeding or the promotion of natural seed sources leads to increases in biomass, dead organic matter carbon pools, and soil carbon pools (Paul et al., 2003). On locations which have low initial soil carbon stocks, afforestation can yield substantial soil carbon accumulation rates. However, sites with high initial soil carbon stocks can show a decline in soil carbon following afforestation (Tate el al., 2005). The harvesting of afforested lands in a sustainable pattern lead to transfer of forest biomass carbon into wood products that store carbon for years to many decades. Carbon stock increases after afforestation vary significantly by tree species and site. Richard and Stokes (2004) estimate the range to be between 1 and 35 t CO2/ha/yr.
Forest management to increase stand- and landscape-level carbon density
Increasing stand- and landscape- level carbon density through forest management activities include harvest systems that maintain partial forest cover, minimize losses of dead organic matter or soil carbon by reducing soil erosion, and by avoiding slash burning and other high-emission activities. Active forest management in the sense of planting after harvest or natural disturbance accelerates tree growth and reduces carbon losses compared to natural regeneration. The economic considerations are typically the main constraint for other forest management options as retaining additional carbon on site delays the revenues from harvest (IPCC, 2007).
Ultimately, impacts of forest management need to be evaluated at landscape level. Increasing harvest rotation lengths will increase certain carbon pools while the same method will decrease others (Kurz et al., 1998).
Increasing off-site carbon stocks in wood products and enhancing product and fuel substitution
Saturation of forest carbon stocks, the point where forest carbon stocks no longer increase due to the attainment of a climax stadium in forest growth, can be addressed with wood products derived from sustainably managed forests. The annual harvest can be equalized with or below the annual forest increment and therefore allowing forest carbon stocks to be maintained or to increase. Additionally, the annual harvest would provide society with an annual carbon flow to meet society's needs of fibre, timber and energy. Wood product based carbon storage can range from several days in the form of biofuels to centuries in the form of houses and furniture (IPCC, 2007). When used to displace fossil fuels, wood fuel can be used to provide sutained carbon benefits and constitutes a large mitigation option.
Other wood products can be used to displacce fossil-fuel intensive construction materials such as concrete,steel, aluminium and plastics. This can result in significant emission reductions (Petersen and Solberg, 2002). For instance, Gustavsson and Sathre (2006) etimate that constructing apartment buildings with wooden frames instead of concrete frames reduces net carbon emissions by 110 to 470 kg CO2 per square meter of floor area on a lifecycle basis. Mitigation benefits can be optimized when wood is first used to replace concrete building material and then be used as a biofuel after disposal (IPCC, 2007).
Many barriers have been identified that preclude the full use of this mitigation potential.
As mentioned, economic considerations are an important barrier that precludes the full use of the mitigation potential of forest management mitigation techniques. Carbon valuation from forest management is currently unsufficiently determined to address this consideration. Other benefits of adopting a more sustainable forest management are considered the primary driver of this shift, instead of the increase of carbon stocks. The other benefits are discussed in more detail below.
Realization of the mitigation potential requires an enabling environment for the technique. The enabling environment depends on institutional capacity, investment capital, technology research and development and transfer, as well as appropriate policies and incentives (IPCC, 2007) In addition, international cooperation and information exchange are required. The IPCC notes that in many regions the absence of an enabling environment is currently a barrier to implementation of forest management mitigation activities. However, the IPCC also notes that there are exceptions in the form of regional successes. Substantial progress has been made in technology development for implementation, monitoring and reporting of carbon benefits but barriers to technology transfer remain.
The efficiency of forest policies themselves are influenced by many factors such as land tenure, institutional and regulatory capacity of governments, the financial competetiveness of forestry and a society's cultural relationship to forests (IPCC, 2007).
In their global forest resources assessment the FAO concludes that the uncontrolled conversion of forests to agricultural land continues at an "alarmingly high rate" in many of the world's countries and that "considerable efforts" are required to ensure that the overall trend in extent of forest resources becomes positive or stable in all regions (FAO, 2010).
On the short run, the IPCC recognizes that the carbon mitigation benefits of reducing deforestation are greater than the benefits of afforestation (IPCC, 2007). This is due to the facts that deforestation is the single biggest source to forestry emissions and that reduced deforestation is immediately noticeable, whereas afforestation is a long-term mitigation option since the trees will collect carbon throughout their growth period. On the long term, the IPCC states that a sustainable forest management strategy aimed at maintaining or increasing forest carbon stocks while producing an annual and sustained yield of timber, fibre or energy from the forest will generate the largest sustained mitigation benefits (IPCC, 2007).
Key to determining the potential of REDD+ are the assumptions of future deforestation rates. These assumptions vary greatly across studies. However, the IPCC outlines that all the studies state that future deforestation is estimated to remain high in the tropics in the short and medium term (IPCC, 2007). For instance, Soares-Filo et al., (2006) predict that by 2050 projected deforestation trends will eliminate 40 % of the current 540 million hectares of the Amazon forests which is estimated to release approximately 117.000 +/- MtCO2 of carbon into the atmosphere. As such, reducing deforestation should be conisdered a high-priority mitigation option within the tropical regions. The potential of REDD+ is elevated due to substantive environmental and other benefits that are characteristic of REDD+ such as biodiversity conservation and preservation and conservation of the forest's social functions. Counteracting loss of tropical forests requires understanding of the causes for deforestation. Chomitz et al., (2006) note that these causes are multiple and local. As such, they conclude that few generalizations of the causes are possible (Chomitz et al., 2006).
The mitigation potential of reducing tropical deforestation is heavily researched. For instance, on the short term, Jung (2005) estimates that the vast majority, up to 93 %, of total mitigation potential in the tropics corresponds to avoided deforestation. Soares-Filo et al. (2006) estimate that by 2050 deforestation potential for the Amazon region cumulatively reaches 62.000 MtCO2.
Not only does forest management options for mitigation result in reduced greenhouse gas emissions, it also results in a variety of socio-economic development and environmental protection benefits.
Avoiding deforestation and afforestation lead to enhanced biodiversity conservation. Avoided deforestation results in the protection of wildlife habitats, and thus protecting the species that occupy that habitat from habitat destruction. Afforestation activities can increase the connectivity of forests, for instance adjacent to nature reserves, and therefore increase the mobility options for species through habitat expansion. This allows for higher biodiversity levels in the different sections of the forests and prevents genetic degradation of species in too small habitats.
Forests have a variety of functions that support our social system that are reduced when forests are degraded or destroyed through unsustainable management practices. For instance, forests provide water erosion control. This means that the forests reduce or prevent the erosion of the soil and prevent run-off. Soil quality is enhanced through avoided deforestation. Additionally, forest disturbances can lead to a dangerous outcome of erosion in the case of heavy rainfalls in which there are no trees to retain soil in that location.
Other forest functions provide income for the local communities as the forest's services can be used and harvested in a sustainable manner. Sustainable forest management can lead to sustained harvest of the forest's products such as wood harvest and forest food. Sustainable forest management may further conserve water resources, reduce river siltation, protect fisheries and investments in hydroelectric power facilities (Parotta, 2002). The IPCC concludes that avoided deforestation, afforestation and sustainable forest management practices have large positive implications for sustainable development.
Table 1 is derived from the IPCC report and provides a summary of several benefits, as well as several negative outcomes of forest management for mitigation.
Dudek et al., (2002) note that climate mitigation policies may have benefits that go beyond global climate protection and actually accrue at the local level. For instance, Figure 6 outlines several other benefits of forests.
The FAO outlines that approximately ten million people are employed in the forest management and conservation sector and many more are diectly dependent on forests for their livelihoods (FAO, 2010). Figure 7 outlines several non-wood forest products.
While protection of forests leads to protection of the environment there are certain basic problems that remain in the evaluation of the contribution of REDD+ (IPCC, 2007). Few major forest-based mitigation analyses have been conducted using new primary data. Therefore, there is still limited insight regarding the impact on soils due to deforestation. There is a lack of integrated views on the many site-specific studies and hardly any intergration has been performed with climate impact studies (IPCC, 2007). In addition, limited development of global baseline scenarios of land use change and their associated carbon balance is performed, which makes the examination of mitigation options difficult. Limited quantitative information on the cost-benefit ratios of mitigation interventions further exacerbates the difficulty of examination.
The IPCC concludes their assesment of forest mitgation options with the notion that forestry can make a "very significant contribution to a low-cost global mitigation portfolio that provides synergies with adaptation and sustainable development (IPCC, 2007).
Since one of the barriers identified that preclude the full use of the mitigation potential are economic considerations, several market based development instruments are proposed that internalize the benefits of mitigation. For instance, market-based development of environmental services from forests such as biodiversity conservation, carbon sequestration, watershed protection and eco-tourims is receiving attention as a tool for promoting sustainable forest management. Development of these markets and behavior of forest owners may influence roundwood markets and availability of wood for conventional uses.
Estimates exist of the required cost of carbon in order to make avoided deforestation as valuable as deforestation. On the long-term, Sohngen and Sedjo (2006) estimate that 27.2 US$/ton of CO2 could potentially eliminate deforestation. Over a fifty year period, this could mean a net cumulative gain of 278.000 MtCO2 relative to the baseline and 422 million additional hectares in forests. The largest gains in carbon would occur in Southeast Asia and South and Central America. Figure 8 is an illustration.
Cost estimates for carbon sequestration projects for different regions compiled by Cacho et al. , (2003) and by Richards and Stokes (2004) show a wide range. The cost is in the range of 0.5 US$ to 7 US$/tCO2 for forestry projects in developing countries, compared to 1.4 US$ to 22 US$/tCO2 for forestry projects in industrialized countries. In the short-term (2008-2012), an estimate of economic potential area available for afforestation/ reforestation under the Clean Development Mechanism (CDM) is estimated to be 5.3 million ha in Africa, Asia and Latin America together, with Asia accounting for 4.4 million ha (Waterloo et al., 2003). Figure 9 is an illustration.
The mitigation costs of reduced deforestation depend on the cause of deforestation (timber or fuelwood extraction, conversion to agriculture, settlement, or infrastructure), the associated returns from the non-forest land use, the returns from potential alternative forest uses, and on any compensation paid to the individual or institutional landowner to change land-use practices.
Afforestation costs vary by land type and region and are affected by the costs of available land, site preparation, and labour. The cost of forest mitigation projects rises significantly when opportunity costs of land are taken into account (VanKooten et al., 2004). A major economic constraint to afforestation is the high initial investment to establish new stands coupled with the several-decade delay until afforested areas generate revenue. The non-carbon benefits of afforestation, such as reduction in erosion or non-consumptive use of forests, however, can more than off-set afforestation cost (Richards and Stokes, 2004).
One of the key aspects of the Conference of the Parties 16 in Cancún December 2010 result, was the outline of a phased approach to strengthen efforts by developing countries to realize REDD+. As such, the Agreements recognize the importance of REDD+ for climate change mitigation. Through a phased approach, national REDD+ strategies should evolve into results-based actions that should be fully measured, reported and verified (PCGCC, 2010a).
Currently, 19 Clean Development Mechanism (CDM) projects related to afforestation/reforestation have been registered with an additional two projects requesting registration. Several afforestation/reforestation methodologies are available. However, at the moment there are no CDM possibilities for avoided deforestation. Information on methodologies to establish baselines for afforestation and reforestation can be found at: http://unfccc.int/2860.php 
Forestry mitigation activities implemented under the Kyoto Protocol, including the Clean Development Mechanism (CDM), have to date been limited. Opportunities to increase activities include simplifying procedures, developing certainty over future commitments, reducing transaction costs, and building confidence and capacity among potential buyers, investors and project participants.
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