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1.
The theoretical potential for carbon forests to off-set greenhouse gas emissions may be high but the achievable rate is influenced by a range of economic and social factors. Economic returns (net present value, NPV) were calculated spatially across the cleared land area in Australia for ‘environmental carbon plantings’. A total of 105 scenarios were run by varying discount rate, carbon price, rate of carbon sequestration and costs for plantation establishment licenses for water interception. The area for which NPV was positive ranged from zero ha for tightly constrained scenarios to almost the whole of the cleared land (104 M ha) for lower discount rate and highest carbon price. For the most plausible assumptions for cost of establishment and commercial discount rate, no areas were identified as profitable until a carbon price of AUD$40 t CO2 ?1 was reached. The many practical constraints to plantation establishment mean that it will likely take decades to have significant impact on emission reductions. Every 1 M ha of carbon forests established would offset about 1.4 % of Australia’s year 2000 emissions (or 7.4 Mt CO2 year?1) when an average rate of sequestration per ha was reached. All studies that predict large areas of potentially profitable land for carbon forestry need to be tempered by the realities that constrain land use change. In Australia and globally, carbon plantings can be a useful activity to help mitigate emissions and restore landscapes but it should be viewed as a long-term project in which co-benefits such as biodiversity enhancement can be realised.  相似文献   

2.
As the world’s population continues to grow, agricultural expansion is expected to increase to meet future food demand often at the expense of other land uses. However, there are limited studies examining the degree to which forest cover will change and the underlying assumptions driving these projections. Focusing on food and forest scenarios for the middle to the end of the current century, we review 63 main scenarios and 28 global modelling studies to address variations in land use projections and evaluate the potential outcomes on forest cover. Further, their potential impacts on greenhouse gases (GHG) emission/sequestration and global temperature are explored. A majority (59%) of scenarios expected a reduction in both forests and pasturelands to make way for agricultural expansion (particularly reference and no mitigation scenarios). In most scenarios, the extent of forest loss is proportional to that of crop gain, which is associated with higher GHG emission and global temperature, loss of carbon sequestration potential and increase in soil erosion. However, 32% of scenarios predicted that meeting food security objectives is possible without leading to further deforestation if there is a global reduction in the demand for energy intensive foods, and improvements in crop yields. Forest gain and lower rates of deforestation are needed to achieve ambitious climate targets over the next decade. Our analysis also highlights carbon taxes (prices), reforestation/afforestation and bioenergy as important variables that can contribute to maintaining or increasing global forest area in the future.  相似文献   

3.
Reducing carbon transaction costs in community-based forest management   总被引:1,自引:0,他引:1  
Abstract

The article considers the potential for community-based forest management (of existing forests) in developing countries, as a future CDM strategy, to sequester and mitigate carbon and to claim credits in future commitment periods. This kind of forestry is cost-effective, and should bring many more benefits to local populations than do afforestation and reforestation, thus contributing more strongly to sustainable development. However, community forest management projects are small-scale, and the transaction costs associated with justifying them as climate projects are likely to be high. A research project being carried out in five developing countries is testing carbon measurement and monitoring methods which can be carried out by community members with very little formal education, which should greatly reduce these transaction costs. Using hand-held computers with GIS capability and attached GPS, villagers with 4 years of primary education are able to accurately map their forest resource and input biomass data from sample plots into a program which calculates carbon values.  相似文献   

4.
Summary Using a high resolution regional climate model we perform multiple January simulations of the impact of land cover change over western Australia. We focus on the potential of reforestation to ameliorate the projected warming over western Australia under two emission scenarios (A2, B2) for 2050 and 2100. Our simulations include the structural and physiological responses of the biosphere to changes in climate and changes in carbon dioxide. We find that reforestation has the potential to reduce the warming caused by the enhanced greenhouse effect by as much as 30% under the A2 and B2 scenarios by 2050 but the cooling effect declines to 10% by 2100 as CO2-induced warming intensifies. The cooling effect of reforestation over western Australia is caused primarily by the increase in leaf area index that leads to a corresponding increase in the latent heat flux. This cooling effect is localized and there were no simulated changes in temperature over regions remote from land cover change. We also show that the more extreme emission scenario (A2) appears to lead to a more intense response in photosynthesis by 2100. Overall, our results are not encouraging in terms of the potential to offset future warming by large scale reforestation. However, at regional scales the impact of land cover change is reasonably large relative to the impact of increasing carbon dioxide (up to 2050) suggesting that future projections of the Australian climate would benefit from the inclusion of projections of future land cover change. We suggest that this would add realism and regional detail to future projections and perhaps aid detection and attribution studies.  相似文献   

5.
Estimates of carbon emissions from the forest sector in Mexico are derived for the year 1985 and for two contrasting scenarios in 2025. The analysis covers both tropical and temperate closed forests. In the mid-1980s, approximately 804,000 ha/year of closed forests suffered major perturbations, of which 668,000 ha was deforestation. Seventy-five percent of total deforestation is concentrated in tropical forests. The resulting annual carbon balance from land-use change is estimated at 67.0 × 106 tons/year, which lead to net emissions of 52.3 × 106 tons/year accounting for the carbon uptake in restoration plantations and degraded forest lands. This last figure represents approximately 40% of the country's estimated annual total carbon emissions for 1985–1987. The annual carbon balance from the forest sector in 2025 is expected to decline to 28.0 × 106 t in the reference scenario and to become negative (i.e., a carbon sink), 62.0 × 106 t in the policy scenario. A number of policy changes are identified that would help achieve the carbon sequestration potential identified in this last scenario.  相似文献   

6.
Liu  Tingxiang  Zhang  Shuwen  Yu  Lingxue  Bu  Kun  Yang  Jiuchun  Chang  Liping 《Theoretical and Applied Climatology》2017,130(3-4):971-978
Currently, US forests constitute a large carbon sink, comprising about 9 % of the global terrestrial carbon sink. Wildfire is the most significant disturbance influencing carbon dynamics in US forests. Our objective is to estimate impacts of climate change, CO2 concentration, and nitrogen deposition on the future net biome productivity (NBP) of US forests until the end of twenty-first century under a range of disturbance conditions. We designate three forest disturbance scenarios under one future climate scenario to evaluate factor impacts for the future period (2011–2100): (1) no wildfires occur but forests continue to age (Saging), (2) no wildfires occur and forest ages are fixed in 2010 (Sfixed_nodis), and (3) wildfires occur according to a historical pattern, consequently changing forest age (Sdis_age_change). Results indicate that US forests remain a large carbon sink in the late twenty-first century under the Sfixed_nodis scenario; however, they become a carbon source under the Saging and Sdis_age_change scenarios. During the period of 2011 to 2100, climate is projected to have a small direct effect on NBP, while atmospheric CO2 concentration and nitrogen deposition have large positive effects on NBP regardless of the future climate and disturbance scenarios. Meanwhile, responses to past disturbances under the Sfixed_nodis scenario increase NBP regardless of the future climate scenarios. Although disturbance effects on NBP under the Saging and Sdis_age_change scenarios decrease with time, both scenarios experience an increase in NBP prior to the 2050s and then a decrease in NBP until the end of the twenty-first century. This study indicates that there is potential to increase or at least maintain the carbon sink of conterminous US forests at the current level if future wildfires are reduced and age structures are maintained at a productive mix. The effects of CO2 on the future carbon sink may overwhelm effects of other factors at the end of the twenty-first century. Although our model in conjunction with multiple disturbance scenarios may not reflect the true conditions of future forests, it provides a range of potential conditions as well as a useful guide to both current and future forest carbon management.  相似文献   

7.
Deforestation has contributed significantly to net greenhouse gas emissions, but slowing deforestation, regrowing forests and other ecosystem processes have made forests a net sink. Deforestation will still influence future carbon fluxes, but the role of forest growth through aging, management, and other silvicultural inputs on future carbon fluxes are critically important but not always recognized by bookkeeping and integrated assessment models. When projecting the future, it is vital to capture how management processes affect carbon storage in ecosystems and wood products. This study uses multiple global forest sector models to project forest carbon impacts across 81 shared socioeconomic (SSP) and climate mitigation pathway scenarios. We illustrate the importance of modeling management decisions in existing forests in response to changing demands for land resources, wood products and carbon. Although the models vary in key attributes, there is general agreement across a majority of scenarios that the global forest sector could remain a carbon sink in the future, sequestering 1.2–5.8 GtCO2e/yr over the next century. Carbon fluxes in the baseline scenarios that exclude climate mitigation policy ranged from −0.8 to 4.9 GtCO2e/yr, highlighting the strong influence of SSPs on forest sector model estimates. Improved forest management can jointly increase carbon stocks and harvests without expanding forest area, suggesting that carbon fluxes from managed forests systems deserve more careful consideration by the climate policy community.  相似文献   

8.
Considered are the contribution of managed forests in the Russian Federation to the climate change softening and the forecast of their carbon-depositing potential in the period till 2050 under different scenarios of the forest management. The sink of CO2 to managed forests is estimated using the flow balance method. The CBM-CFS3 model worked out in the Canadian Forestry Service is used for predicting the carbon budget. It is found out that managed forests absorb 473.8 Mt of CO2 per year. The carbon sink is caused by the reduction of the volume of the forest use and by the regeneration of cutover stands of previous years. Depending on the conditions of the forest use, by 2020 the CO2 sink to managed forests will amount to 466–632 Mt/year and will be able to compensate from 21 to 29% of industrial emissions of greenhouse gases. The carbon absorption by managed forests will decrease to 105–235 Mt/year by 2050. To maintain and increase the carbon-depositing potential of managed forests, the Russian Federation needs the development of the system of purposeful activities on strengthening the protection against forest fires and on the intensification of forest reproduction.  相似文献   

9.
This article describes a ‘tax and trade' emission regulations system that controls both emission costs and emission quantities. Emitters are taxed at a fixed price on carbon emissions and the government uses the tax revenue to buy carbon offsets on existing emissions markets. Unlike a traditional carbon tax, regulated firms may also produce carbon credits which may be sold to the government. Thus, the government bears the compliance cost risk rather than an individual firm and has control over the number of offsets purchased and the effective emission reduction. This unusual form of hybrid has potential political advantages of creating an economic incentive on corporate choices (at the margin) substantially greater than the actual trading price, and with lower financial transfers than in most schemes.

Policy relevance

The article presents a hybrid carbon emissions system that adds to the growing discussion of hybrid policy instruments which could be implemented by policy makers, particularly in nations without current cap and trade policies.  相似文献   

10.
Restoring tree cover in tropical countries has the potential to benefit millions of smallholders through improvements in income and environmental services. However, despite their dominant landholding shares in many countries, smallholders’ role in restoration has not been addressed in prior global or pan-tropical restoration studies. We fill this lacuna by using global spatial data on trees and people, national indicators of enabling conditions, and micro-level expert information. We find that by 2050, low-cost restoration is feasible within 280, 200, and 60 million hectares of tropical croplands, pasturelands, and degraded forestlands, respectively. Such restoration could affect 210 million people in croplands, 59 million people in pasturelands and 22 million people in degraded forestlands. This predominance of low-cost restoration opportunity in populated agricultural lands has not been revealed by prior analyses of tree cover restoration potential. In countries with low-cost tropical restoration potential, smallholdings comprise a significant proportion of agricultural lands in Asia (∼76 %) and Africa (∼60 %) but not the Americas (∼3%). Thus, while the Americas account for approximately half of 21st century tropical deforestation, smallholder-based reforestation may play a larger role in efforts to reverse recent forest loss in Asia and Africa than in the Americas. Furthermore, our analyses show that countries with low-cost restoration potential largely lack policy commitments or smallholder supportive institutional and market conditions. Discussions among practitioners and researchers suggest that four principles – partnering with farmers and prioritizing their preferences, reducing uncertainty, strengthening markets, and mobilizing innovative financing – can help scale smallholder-driven restoration in the face of these challenges.  相似文献   

11.
Abstract

The Ninth Conference of the Parties (COP-9) decided to adopt an accounting system based on expiring carbon credits to address the problem of non-permanent carbon storage in forests established under the Clean Development Mechanism (CDM). This article reviews and discusses carbon accounting methods that were under consideration before COP-9 and presents a model which calculates the minimum area that forest plantation projects should reach to be able to compensate CDM transaction costs with the revenues from carbon credits. The model compares different accounting methods under various sets of parameters on project management, transaction costs, and carbon prices. Model results show that under current carbon price and average transaction costs, projects with an area of less than 500 ha are excluded from the CDM, whatever accounting method is used. Temporary crediting appears to be the most favorable approach to account for non-permanent carbon removal in forests and also for the feasibility of smaller projects. However, lower prices for credits with finite lifetimes may prevent the establishment of CDM forestry projects. Also, plantation projects with low risk of unexpected carbon loss and sufficient capacity for insuring or buffering the risk of carbon re-emission would benefit from equivalence-adjusted average carbon storage accounting rather than from temporary crediting.  相似文献   

12.
The world’s forests play an important role in regulating climate change through their capacity to sequester carbon. At the same time, they are also increasingly vulnerable to the impacts of climate change. In the western Canadian province of British Columbia, changes in temperature, precipitation, and disturbance regimes are already impacting forests. In response to these observed and anticipated changes, adapted reforestation practices are being developed and proposed as a means to help forest ecosystems adjust to changing climatic conditions. One such practice under consideration is assisted migration—planting species within or outside of the native historical range into areas that are anticipated to be climatically suitable in the future. We used a survey of British Columbia’s population at large (n?=?1923) to quantify levels of support for a range of potential reforestation options (including assisted migration) to adapt to climate change, and to explore what factors can help predict this support. Our findings reveal that the likely location of potential public controversy resides not with the potential implementation of assisted migration strategies per se, but rather with assisted migration strategies that involve movement of tree species beyond their native range.  相似文献   

13.
Floodplain restoration offers an opportunity to enhance communities’ resilience to flooding. However, the degree to which these interventions mitigate damages is often unknown, and identifying the best locations for implementation is a challenge. Further, the extent to which the benefits of flood mitigation are equitably distributed within communities is rarely considered in restoration projects. Here, we develop a novel framework to optimize investments in floodplain restoration that maximizes the utility of avoided damages from flood inundation for a range of budgetary constraints. We estimate the expected reduction in flood damages from restoration interventions by integrating a hydraulic flood model and an economic damage cost model. Using equity-weighted utility functions, we explicitly evaluate how the value of reduction in flood damages varies for different property owners. We demonstrate the potential of this approach in the Lewis Creek watershed, located in Vermont, USA. Under all optimal scenarios, the benefits of avoided flood damages over a 100-year time period outweigh the costs of restoration by at least 5-to-1. Floodplain restoration has the potential to reduce the present value of damages by up to $400,000, a 5% decrease from the baseline, at a cost of only $75,000. We also show that the equity-weighted utility of flood mitigation increase when restoration interventions protect the lowest-income property owners, particularly those who live in mobile homes. Together, our results illuminate the importance of evaluating the distribution of benefits and costs associated with alternative restoration strategies, as well as underscore the capacity for floodplain restoration to build resilience to flooding.  相似文献   

14.
We analyze and integrate energy andforestry carbon mitigation scenarios for Mexicobetween the year 1994 and 2010. The energy optionsrange from efficient end-use technologies to renewabletechnologies for electricity generation. Forestryoptions include avoiding deforestation through themanagement of native forests, and two afforestationoptions: restoration plantations and agroforestrysystems. The methodology utilized to evaluatedifferent energy and forestry scenarios is based on a`bottom up' model. In the year 2010, total carbonemissions will reach 879 Tg of CO2, of which 83%comes from energy consumption. The total carbonmitigation potential reaches 348 Tg of CO2 by2010, 62% of which comes from forestry options.Mitigation costs range from $–45.9/ton CO2 to$106.4/ton CO2. Several options, particularlyconcerning energy technologies, are cost effectivefrom a national perspective. In each sector, differentbarriers can hinder the implementation of mitigationalternatives.  相似文献   

15.
Forests play an important role in sequestrating carbon from the atmosphere. Since the 1980s, reforestation activities have been implemented in the area surrounding the Qianyanzhou Forest Experimental Station in Jiangxi Province, China. Farmland and heavily eroded waste land were replanted with fruit, orchards and forest plantations. The area surrounding the Qianyanzhou Forest Experimental Station was selected as research site to analyze the potential of reforestation in carbon sequestration. This study evaluates the variation of soil organic carbon storage under the different land use types. Soil organic carbon storage varied greatly with land use types. From 1984 to 2002, soil organic carbon storage increased 2.45 × 106 kg across eight land use types. This study demonstrates the potential for carbon sequestration in soils from reforestation. However, a complete understanding of soil carbon fluxes at the landscape scale will depend on the potential and retention period of soil organic carbon.  相似文献   

16.
The potential impacts of CO2-induced climate change on terrestrial carbon storage was estimated using the Holdridge Life-Zone Classification and four climate change scenarios derived from general circulation models. Carbon values were assigned to life-zones and their associated soils from published studies. All four scenarios suggest an increase in area occupied by forests although details of predicted patterns vary among the scenarios. There is a poleward shift of the forested zones, with an increase in the areal extent of tropical forests and a shift of the boreal forest zone into the region currently occupied by tundra. Terrestrial carbon storage increased from 0.4% (8.5 Gt) to 9.5% (180.5 Gt) above estimates for present conditions. These changes represent a potential reduction of 4 to 85 ppm on elevated atmospheric CO2 levels.  相似文献   

17.
18.
基于CGE模型的上海市碳排放交易的环境经济影响分析   总被引:1,自引:0,他引:1  
通过应用上海市能源-环境-经济CGE模型,针对碳排放交易机制所涉及的重要要素,包括覆盖行业和分配方式等设计不同的情景,模拟了在不同的就业条件下碳排放交易机制对经济的影响和对传统污染物的协同减排效应。结果表明,如果碳交易纳管行业释放出来的劳动力能及时被其他行业吸纳和消化,则碳交易对GDP的整体影响为正,碳交易的实施产生了双重红利。若劳动力不能及时转移,则碳交易对GDP的整体影响为负,2020年不同情景下GDP损失为1.5%~2.4%;相比覆盖部分行业,在覆盖全部行业的情景下,碳价格最低,从2013年的30元/t增加到2020年的202元/t,对高耗能行业的竞争力影响相对较小,但是由于所有行业都纳入到纳管范围,使得对GDP的负面影响最大;此外,实施碳交易能明显改善环境效益,有助于推动SO2和NOX减排目标的实现。  相似文献   

19.
Alex Y. Lo 《Climate Policy》2016,16(1):109-124
China has introduced several pilot emission trading schemes to build the basis for a national scheme. The potential scale of this initiative raises prospects for a regional carbon trading network as a way to further engage other major Asian economies. However, the Chinese carbon markets rest upon a unique political-economic context and institutional environment that are likely to limit their development and viability. This article offers an overview of such structural economic and political constraints. Four main challenges are identified, namely, inadequate domestic demand, limited financial involvement, incomplete regulatory infrastructure, and excessive government intervention. The first two challenges concern economic dimensions and may be partially addressed by the incentives created by the newly introduced emission trading schemes. The other two are more deeply entrenched in the dominant political system and governing practice. They require fundamental changes to the ways in which the state and the market interact. The success of China's carbon market reform depends crucially on the ability of the ongoing efforts to transform the distorted state–market relationship.

Policy relevance

The burgeoning carbon markets offer opportunities for emissions mitigation at lower costs and enable circulation of a new form of capital, i.e. carbon credits, across borders. China accounts for a gigantic share of global GHG emissions and has the potential to significantly scale up these opportunities. There are clear implications for market developers and participants worldwide, including climate policy makers who attempt to link their emission trading schemes to other schemes, firms who seek to take advantage of the inexpensive carbon offsets generated in developing countries, international financial institutions who endeavour to establish their business in an emerging major carbon market, etc. This article can inform their decisions by identifying key issues that may undermine their ability to achieve these goals. Policy makers and stakeholders will benefit from this analysis, which shows how the Chinese carbon markets operate in ways that may be different from their experience elsewhere.  相似文献   


20.
The establishment of a carbon market assumes that there is an effective means of transforming price information into technical carbon reduction measures. However, empirical evidence reveals that the links between price information and carbon management strategies are far from obvious. To understand how delegating CO2 responsibility affects CO2 trading behaviour, this article proposes a neo-institutionalist approach to answering the question of why companies became sellers, buyers or a combination of both during phase I of the European Emissions Trading Scheme (EU ETS). Original data from a survey on companies that participated in this scheme were collected and analysed. It was assumed that the trading scheme offered two ways to delegate decisions regarding emissions trading: decoupling from technical knowledge and financialization (i.e. delegating to financial departments) or coupling using technicalization (i.e. delegating to manufacturing departments). The results support the hypothesis that a company that adopts a decoupling strategy is more likely to buy certificates to fulfil their emissions targets. Adopting a coupling strategy indicates that a company is more likely to become a seller, all else equal. Professional identity is the theoretical basis for this relationship. Delegating carbon management to different departments represents either a stronger coupling or a stronger decoupling from core technological processes.

Policy relevance

The transaction data from phase I of the EU ETS open new questions and possibilities regarding the reasons that drive selling and buying in companies. It is important to look not only at the traditional sources of transaction costs, but rather also at the reasons for these tensions. One important source is the professional education of the people in charge of the EU ETS. Tailored information that directly addresses the different professional backgrounds of managers working in both financial departments and more technical departments might help to lower these types of transaction costs. In today's context, important emitter countries, such as China and Korea, have launched their own emissions markets, copying many aspects of the EU ETS. For the positive development of these markets and as a way of establishing a global emissions market, these new schemes should learn from the EU ETS experience.  相似文献   

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