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1.
The current framework through which greenhouse gas emissions and removals in the land use sector are accounted under the Kyoto Protocol has several problems. They include a complex structure, onerous monitoring and reporting requirements, and potential for omission of some important fluxes. One solution that may overcome some of these problems is to include all lands and associated processes within a country's jurisdiction, rather than restrict accounting to specific nominated land categories or activities. Ideally, the accounting approach should cover all significant biospheric sources and sinks, avoid biased or unbalanced accounting, avoid leakage and require no arbitrary adjustments to remedy unintended consequences. Furthermore, accounting should focus on the direct human-induced component of biospheric emissions/removals so that debits/credits can be allocated equitably and provide appropriate incentives to adopt land-use management options with beneficial outcomes for the atmosphere.This paper focuses on biospheric emissions and removals resulting from carbon stock changes. It considers four alternative accounting options that include all land areas: Gross-Net Accounting, Net-Net Accounting, Net Accounting with Negotiated Baselines and the Average Carbon Stocks approach. Each option is described, and assessed with respect to defined criteria for effectiveness. Gross-Net Accounting and Net-Net Accounting do not adequately distinguish the anthropogenic component of carbon-stock changes from indirect and natural effects, so large undeserved credits or debits could be created. Under Net Accounting with Negotiated Baselines, countries’ projected emissions and removals during the commitment period would be taken into account in the negotiation of emissions targets. In the commitment period, countries would then gain credits/debits for biospheric removals/emissions. Difficulties with this approach would lie in reaching agreed baselines for emissions and removals for individual countries, and, if desired, in factoring out residual effects of natural variability on emissions/removals. Under the Average Carbon Stocks approach, debits/credits for changes in land use or management practices would be based on the changes in long-term average carbon stocks associated with changes in specific land use and management regimes. This approach thereby directly identifies the anthropogenic component, and assigns debits and credits accordingly. It may prove problematic, however, for countries to accept long-term averages rather than observable realised carbon-stock changes as the basis for accounting. Thus, none of the options is without its drawbacks, but Net Accounting with Negotiated Baselines and the Average Carbon Stocks approach could potentially be used as the basis of developing a future ‘all lands’ accounting framework.  相似文献   

2.
In its attempt to provide quantitative limits on greenhouse gas emissions, the Kyoto protocol accepts the principle that sequestration of carbon in the terrestrial biosphere can be used to offset emissions of carbon from fossil-fuel combustion. Whether or not the Kyoto protocol ever comes into force, it is worthwhile to understand how carbon sequestration might be treated in any mitigation plan that provides a tax or ration on carbon emissions. Emission credits, as proposed for the energy sector, are based on the idea that a prevented emission is prevented forever, and emission credits might be traded among parties. In the event that sequestered carbon is subsequently released to the atmosphere, it would be advantageous to agree what the liability is and who assumes that liability. We describe a system whereby emissions credits could be rented, rather than sold, when carbon is sequestered but permanence of sequestration is either not certain or not desired. Our proposal is similar to that offered by the government of Colombia except that it casts these temporary emissions credits into the traditional concepts of rental agreements and it clarifies the opportunities for secondary transactions. A rental contract for emissions credits would establish continuous responsibility for sequestered carbon; credit would be assigned when carbon is sequestered and debits would accrue when carbon is emitted.  相似文献   

3.
The Kyoto Protocol was agreed on by more than 150 nations in December, 1997 and (if and when ratified) will establish international commitments to reduce emissions of greenhouse gases to the atmosphere. Under the Kyoto Protocol, some of the carbon emissions and removals within the land-use change and forestry sector can be counted toward a country's commitments for greenhouse gas emissions reductions. In addition to the impacts that land-use practices have on CO2 emissions from fossil-fuel combustion, changes in the carbon stocks of forests (possibly including forest soils) caused by the direct human activities afforestation, reforestation and deforestation and taking place in the `first commitment period' (2008–2012), are to be accounted for under the Kyoto Protocol. Credits for carbon sinks in the biosphere are limited to projects initiated since 1990. A modified version of the model GORCAM has been used to assess eligible emission-reduction credits under the Kyoto regime and to illustrate how the optimal forest-based strategy for carbon dioxide mitigation might change under the provisions of the Kyoto Protocol. The Kyoto Protocol offers rewards for only some of the changes in carbon stocks that might occur and hence the forestry project that produces the most emission reduction credits under the Kyoto Protocol is not necessarily the same project that produces the greatest benefit for net emissions of carbon dioxide to the atmosphere. Supplementing the Protocol with appropriate definitions, interpretations and agreements could help to make sure that it does not provide incentive for activities that run counter to the objectives of the Framework Convention on Climate Change.  相似文献   

4.
The rate of carbon accumulation in the atmosphere can be reduced by decreasing emissions from the burning of fossil fuels and by increasing the net uptake (or reducing the net loss) of carbon in terrestrial (and aquatic) ecosystems. The Kyoto Protocol addresses both the release and uptake of carbon. Canada is developing a National Forest Carbon Monitoring, Accounting and Reporting System in support of its international obligations to report greenhouse gas sources and sinks. This system employs forest-inventory data, growth and yield information, and statistics on natural disturbances, management actions and land-use change to estimate forest carbon stocks, changes in carbon stocks, and emissions of non-CO2 greenhouse gases. A key component of the system is the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS). The model is undergoing extensive revisions to enable analyses at four spatial scales (national, provincial, forest management unit and stand) and in annual time steps. The model and the supporting databases can be used to assess carbon-stock changes between 1990 and the present, and to predict future carbon-stock changes based on scenarios of future disturbance rates and management actions.  相似文献   

5.
One of the largest sources of global greenhouse gas emissions can be addressed through conservation of tropical forests by channeling funds to developing countries at a cost-savings for developed countries. However, questions remain to be resolved in negotiating a system for including reduced emissions from deforestation and forest degradation (REDD) in a post-Kyoto climate treaty. The approach to determine national baselines, or reference levels, for quantifying REDD has emerged as central to negotiations over a REDD mechanism in a post-Kyoto policy framework. The baseline approach is critical to the success of a REDD mechanism because it affects the quantity, credibility, and equity of credits generated from efforts to reduce forest carbon emissions. We compared outcomes of seven proposed baseline approaches as a function of country circumstances, using a retrospective analysis of FAO-FRA data on forest carbon emissions from deforestation. Depending upon the baseline approach used, the total credited emissions avoided ranged over two orders of magnitude for the same quantity of actual emissions reductions. There was also a wide range in the relative distribution of credits generated among the five country types we identified. Outcomes were especially variable for countries with high remaining forest and low rates of deforestation (HFLD). We suggest that the most credible approaches measure emissions avoided with respect to a business-as-usual baseline scenario linked to historic emissions data, and allow limited adjustments based on forest carbon stocks.  相似文献   

6.
To participate in the potential market for carbon credits based on changes in the use and management of the land, one needs to identify opportunities and implement land-use based emissions reductions or sequestration projects. A key requirement of land-based carbon (C) projects is that any activity developed for generating C benefits must be additional to business-as-usual. A rule-based model was developed and used that estimates changes in land-use and subsequent carbon emissions over the next twenty years using the Eastern Panama Canal Watershed (EPCW) as a case study. These projections of changes in C stocks serve as a baseline to identify where opportunities exist for implementing projects to generate potential C credits and to position Panama to be able to participate in the emerging C market by developing a baseline under scenarios of business-as-usual and new-road development. The projections show that the highest percent change in land use for the new-road scenario compared to the business-as-usual scenario is for urban areas, and the greatest cause of C emission is from deforestation. Thus, the most effective way to reduce C emissions to the atmosphere in the EPCW is by reducing deforestation. In addition to affecting C emissions, reducing deforestation would also protect the soil and water resources of the EPCW. Yet, under the current framework of the Clean Development Mechanism (CDM), only credits arising from reforestation are allowed, which after 20 years of plantation establishment are not enough to offset the C emissions from the ongoing, albeit small, rate of deforestation in the EPCW. The study demonstrates the value of spatial regional projections of changes in land cover and C stocks: The approach helps a country identify its potential greenhouse gas (GHG) emission liabilities into the future and provides opportunity for the country to plan alternative development pathways. It could be used by potential project developers to identify which types of projects will generate the largest C benefits and provide the needed baseline against which a project is then evaluated. Spatial baselines, such as those presented here, can be used by governments to help identify development goals. The development of such a baseline, and its expansion to other vulnerable areas, well positions Panama to respond to the future market demand for C offsets. It is useful to compare the projected change in land cover under the business-as-usual scenario to the goals set by Law 21 for the year 2020. Suggested next steps for analysis includeusing the modeling approach to exploreland-use, C dynamics and management ofsecondary forests and plantations, soilC gains or losses, sources ofvariability in the land use and Cstock projections, and other ecologicalimplications and feedbacks resulting fromprojected changes in land cover.  相似文献   

7.
The goal of the Climate Convention and its Kyoto Protocol is to stabilize greenhouse gas concentrations in the atmosphere at a safe level. This requires both strict limits on emissions from fossil fuels and effective management of biotic carbon stocks. If fossil fuel emissions from 1990 to 2100 are limited to 600 PgC, biotic carbon stocks must increase by 120 PgC to stabilize CO2 concentrations at 450 ppmv. Establishing an appropriate policy regime to accomplish this goal is complicated by a factor of six discrepancy between estimates of the current biotic sink based on national emissions inventories compared with global carbon cycle model calculations. Appropriate policies must also be designed to create incentives for technological innovation in the energy sector and minimize the risk of granting emission credits for biotic carbon sequestration that proves to be temporary.  相似文献   

8.
Carbon emissions from tropical deforestation account for about 25% of all anthropogenic carbon dioxide emissions but cannot be credited under current climate change agreements. In the discussions around the architecture of the post-2012 climate regime, the possibility of including credits for reduced emissions from deforestation arises. The paper reviews two approaches for this, compensated reductions (CR) as proposed by Santilli et al. and the Joint Research Centre proposal that combine voluntary commitments by non-Annex I countries to reduce emissions from deforestation with carbon market financing. Both approaches have the clear advantages of simplicity and the possibility of fitting to an evolving greenhouse gas emission reduction regime. The authors consider the strengths and limitations of each proposal and build upon them to address several implementation challenges and options for improvement. Given the urgency of avoiding dangerous climate change, the timely development of technically sound, politically acceptable, cost-effective and practicable measures to reduce emissions from deforestation and forest degradation is essential. These two approaches take us a step closer to this goal, but they need to be refined rapidly to enable this goal to be realised.  相似文献   

9.
Under the United Nations Framework Convention on Climate Change, more than 160 countries are required to report their national greenhouse gas inventories. To help countries meet this requirement, the Intergovernmental Panel on Climate Change (IPCC) prepared guidelines for inventorying greenhouse gases. These guidelines are regularly reviewed to ensure that they are based on the best scientific knowledge. In May 1998, in Dakar, Senegal, an IPCC expert meeting reviewed and evaluated three approaches for accounting for carbon from forest harvesting and wood products. They are the atmospheric-flow, stock-change and production approaches. In the future, governments may decide to include one of the three approaches in the land-use change and forestry module of the IPCC Guidelines for National Greenhouse Gas Inventories. Here, we demonstrate how such approaches can be evaluated using technical, scientific and policy criteria. The purpose of this evaluation is to help policy-makers potentially choose an approach for the IPCC Guidelines. This paper presents the framework of the evaluation by separating the technical and policy issues of each approach, but it does not make policy recommendations. On technical and scientific grounds, a group of experts found that the three approaches gave similar results at a global level. Data availability is not a critical factor in choosing between the approaches. However, at the national level, the approaches can differ significantly, for example, in terms of their system boundaries. Depending on technical features of each approach, credits and debits for CO2 flows or changes in carbon stock in wood products are accounted for differently among countries that produce or consume wood. This leads to differing incentives for conserving or enhancing carbon stocks in forests, the use of imported wood products and woodfuels and waste minimisation strategies. Each approach has different implications.  相似文献   

10.
This paper describes the relevant text of the Kyoto Protocol and its implications for land-use change and forestry (LUCF) activities and addresses some of the technical issues that merit further consideration and clarification before the treaty comes into force. Although the phrasing of the Protocol is sometimes ambiguous and the opportunities limited, the Protocol does provide for some selected forest-related activities to be used to meet national commitments for the reduction of greenhouse gas emissions. To implement the forest-related portions of the Protocol, most importantly: (1) a clear definition for the word ‘reforestation' is required, (2) contradictory wording in Article 3.3 needs to be clarified to establish how credits are to be measured, (3) further thought should be given to the sentence in Article 3.7 which provides that countries with a net carbon sink in LUCF in 1990 cannot include emissions from land-use change in their 1990 baseline, whereas countries with a net carbon source in LUCF can include those emissions in their 1990 baseline, (4) the rules and baseline issues for joint implementation and the clean development mechanism need to be clarified and (5) inclusion of additional forest management activities needs to be considered.  相似文献   

11.
When forest is harvested some of the forest carbon ends up in wood products. If the forest is managed so that the standing stock of the forest remains constant over time, and the stock of wood products is increasing, then carbon dioxide is being removed from the atmosphere in net and this should be reflected in accounting for greenhouse gas emissions. We suggest that carbon sequestration in wood products requires cooperation of multiple parties; from the forest owner to the product manufacturer to the product user, and perhaps others. Credit for sequestering carbon away from the atmosphere could acknowledge the contributions of these multiple parties. Accounting under a cap-and-trade or tax system is not necessarily an inventory system, it is a system designed to motivate and/or reward an environmental objective. We describe a system of attribution whereby credits for carbon sequestration would be shared among multiple, contributing parties. It is hoped that the methodology outlined herein proves attractive enough to parties concerned to spur them to address the details of such a system. The system of incentives one would choose for limiting or controlling greenhouse gas emissions could be quite different, depending on how the attribution for emissions and sequestration is chosen.  相似文献   

12.
Waste management is a significant source of methane (CH4) emissions. CH4 is second to carbon dioxide (CO2) the most important anthropogenic greenhouse gas. In this article the methodology and results from a study on the reduction potential of alternative waste treatment strategies in mitigating the greenhouse impact are presented. The objective is to provide information to decision makers so that the greenhouse issue can be included in the decision making on waste management strategies. The potential cost-effectiveness of reducing the greenhouse impact of alternative waste treatment strategies in three communities of different size in Finland is assessed. The estimation of the greenhouse impact includes estimates of the greenhouse gas (GHG) emissions, the amount of carbon (C) stored at landfills (Csink) and the emission savings that can be achieved by using waste for energy production (assumed decrease in the use of fossil fuels). Landfill gas recovery with energy production was found to be the most-efficient way in reducing the greenhouse impact from large landfills. Burning of all the waste or the combustible fraction in municipal solid waste (MSW) was also an efficient method to reduce greenhouse gas emissions, especially if the energy produced can reduce the burning of fossil fuels. Emissions from transportation of waste are small compared with the emissions from landfills. Even if the transportion mileage is doubled due to increasing separation and recycling the greenhouse impact of transportation would be only 3–4 percent of the impact of landfilling the waste.  相似文献   

13.
The article quantifies the size of ‘hidden’ social costs that are incurred by forestry offsets in the voluntary market that promise to offset present emissions sometime in the future. It does this by estimating the difference between the social costs of carbon (C) emitted and of costs offset by removal of C from the atmosphere by reforestation/afforestation. All current attempts to make forestry offsets more reliable focus on quality control rather than the mismatch of the timing of emissions and their offset. Recommendations that follow from the analysis are twofold. First, that markets for carbon dioxide equivalent (CO2e) removals by voluntary offsets should be confined to the annual incremental removals actually achieved. Second, the promoters of voluntary offsets projects should declare the annual stream of carbon credits and debits expected so that buyers can place a present value on such projects.  相似文献   

14.
The lower troposphere is an excellent receptacle, which integrates anthropogenic greenhouse gases emissions over large areas. Therefore, atmospheric concentration observations over populated regions would provide the ultimate proof if sustained emissions changes have occurred. The most important anthropogenic greenhouse gas, carbon dioxide (CO(2)), also shows large natural concentration variations, which need to be disentangled from anthropogenic signals to assess changes in associated emissions. This is in principle possible for the fossil fuel CO(2) component (FFCO(2)) by high-precision radiocarbon ((14)C) analyses because FFCO(2) is free of radiocarbon. Long-term observations of (14)CO(2) conducted at two sites in south-western Germany do not yet reveal any significant trends in the regional fossil fuel CO(2) component. We rather observe strong inter-annual variations, which are largely imprinted by changes of atmospheric transport as supported by dedicated transport model simulations of fossil fuel CO(2). In this paper, we show that, depending on the remoteness of the site, changes of about 7-26% in fossil fuel emissions in respective catchment areas could be detected with confidence by high-precision atmospheric (14)CO(2) measurements when comparing 5-year averages if these inter-annual variations were taken into account. This perspective constitutes the urgently needed tool for validation of fossil fuel CO(2) emissions changes in the framework of the Kyoto protocol and successive climate initiatives.  相似文献   

15.
This study examines the correlation between deforestation, carbon dioxide emissions and potential causal factors of land-use change within an area of 2.7 million ha in Chiapas, southern Mexico between 1975 and 1996. Digitized land-use maps and interpreted satellite images were used to quantify land-use changes. Geo-referenced databases of population and digitized maps of roads and topography were used to determine which factors could be used to explain observed changes in land-use. The study analyzed the relationship between carbon emissions during this period and two types of possible causal factors: “predisposing” factors that determine the susceptibility of a particular area of forest to change (slope, distance to agriculture and roads, land tenure) and “driving” factors representing the pressures for change (population density, poverty). The correlated factors were combined in risk matrices, which show the proportion of vulnerable carbon stocks lost in areas with defined social, economic and environmental characteristics. Such matrices could be used to predict future deforestation rates and provide a verifiable evidence-base for defining baseline carbon emissions for forest conservation projects. Based on the results of the analysis, two matrices were constructed, using population density as the single most important driving factor and distance from roads and distance from agriculture as the two alternatives for the predisposing factors of deforestation.  相似文献   

16.
The C-Lock system was developed to address the need for an improved method of quantifying and certifying project-level carbon emission reduction credits (CERC). It was designed to enable individual landowners to efficiently quantify, certify, pool, market and trade CERCs generated by agricultural management practices. We provide a general overview of the C-Lock system as it has been implemented for the USA State of South Dakota. C-Lock is comprised of four linked components: a web interface, a client database, a Geographic Information System (GIS) database of soil, climate and generalized land use history parameters, and the CENTURY soil carbon model. The user-friendly interface elicits generalized land-use and crop history information from the client from 1900 through 1989, then explicit annual information from 1990 onward. A climate-zone level landuse and crop management database is used to fill in gaps in the client-provided data. These data are used to drive the CENTURY model, which estimates annual changes in soil carbon stocks. Monte Carlo simulation is used to estimate uncertainty bounds, and these are applied to the CENTURY outputs in order to provide probabilistic estimates of accrued CERCs in a manner that is transparent and verifiable. In a demonstration application, CERCs are estimated for three different land-use scenarios on a representative field in eastern South Dakota: reduced tillage or conservation (no-till) management of a corn (maize)/wheat/soybean rotation, and enrollment in the Conservation Reserve Program, which entails establishing permanent grass cover. The credits are based on a business-asusual scenario of conventional tillage.  相似文献   

17.
While bioenergy plays a key role in strategies for increasing renewable energy deployment, studies assessing greenhouse gas (GHG) emissions from forest bioenergy systems have identified a potential trade-off of the system with forest carbon stocks. Of particular importance to national GHG inventories is how trade-offs between forest carbon stocks and bioenergy production are accounted for within the Agriculture, Forestry and Other Land Use (AFOLU) sector under current and future international climate change mitigation agreements. Through a case study of electricity produced using wood pellets from harvested forest stands in Ontario, Canada, this study assesses the implications of forest carbon accounting approaches on net emissions attributable to pellets produced for domestic use or export. Particular emphasis is placed on the forest management reference level (FMRL) method, as it will be employed by most Annex I nations in the next Kyoto Protocol Commitment Period. While bioenergy production is found to reduce forest carbon sequestration, under the FMRL approach this trade-off may not be accounted for and thus not incur an accountable AFOLU-related emission, provided that total forest harvest remains at or below that defined under the FMRL baseline. In contrast, accounting for forest carbon trade-offs associated with harvest for bioenergy results in an increase in net GHG emissions (AFOLU and life cycle emissions) lasting 37 or 90 years (if displacing coal or natural gas combined cycle generation, respectively). AFOLU emissions calculated using the Gross-Net approach are dominated by legacy effects of past management and natural disturbance, indicating near-term net forest carbon increase but longer-term reduction in forest carbon stocks. Export of wood pellets to EU markets does not greatly affect the total life cycle GHG emissions of wood pellets. However, pellet exporting countries risk creating a considerable GHG emissions burden, as they are responsible for AFOLU and bioenergy production emissions but do not receive credit for pellets displacing fossil fuel-related GHG emissions. Countries producing bioenergy from forest biomass, whether for domestic use or for export, should carefully consider potential implications of alternate forest carbon accounting methods to ensure that potential bioenergy pathways can contribute to GHG emissions reduction targets.  相似文献   

18.
The Scottish Government has proposed reducing Scotland’s greenhouse gas (GHG) emissions by at least 80% by 2050, compared to the 1990 baseline level. It is not yet clear how these reductions will be achieved, but it is likely that all sectors will be expected to make some contribution. Depending on their farm activities, farmers have different sets of abatement alternatives—the challenge facing them, however, is in finding strategies that help to meet reduction targets while maintaining their income. In this paper, we use an agent-based modelling approach to study the implications of carbon trading design options aimed at reducing GHG emissions in the agricultural sector, such as auctions, fixed carbon prices, or carbon credit banking. The feasibility of carbon trading scheme options is assessed regarding their ability to ensure that farmers obtain carbon credits at an affordable and adequate price, since low prices would reward farmers not adopting on-farm abatement options and high prices would encourage non-compliance to targets, thus increasing enforcement costs. Assuming a closed market within the agricultural sector, this study shows that farmers may face up to 50% loss of income to achieve a 30% reduction target if this requires a cut in production. However, market design options such as credits banking may allow farmers to progressively adapt to the scheme constraints. At an individual level, the rate of on-farm compliance and the mandated emission reduction target will determine which farmer strategy is the most efficient to cope with a trading scheme.  相似文献   

19.
The capacity to partition natural, indirect, and direct human-induced effects on terrestrial carbon (C) sources and sinks is necessary to be able to predict future terrestrial C dynamics and thus their influence on atmospheric CO2 growth. However, it will take a number of years before we can better attribute quantitative estimates of the contribution of various C processes to the net C balance. In a policy context, factoring out natural and indirect human-induced effects on C sources and sinks from the direct human-induced influences, is seen as a requirement of a C accounting approach that establishes a clear and unambiguous connection between human activities and the assignment of C credits and debits. We present options for factoring out various groups of influences including climate variability, CO2 and N fertilization, and legacies from forest management. These are: (i) selecting longer accounting or measurement periods to reduce the effects of inter-annual variability; (ii) correction of national inventories for inter-annual variability; (iii) use of activity-based accounting and C response curves; (iv) use of baseline scenarios or benchmarks at the national level; (v) stratification of the landscape into units with distinct average C stocks. Other, more sophisticated modeling approaches (e.g., demographic models in combination with forest inventories; process-based models) are possible options for future C accounting systems but their complexity and data requirements make their present adoption more difficult in an inclusive international C accounting system.  相似文献   

20.
The REDD-ALERT (Reducing Emissions from Deforestation and Degradation from Alternative Land Uses in the Rainforests of the Tropics) project started in 2009 and finished in 2012, and had the aim of evaluating mechanisms that translate international-level agreements into instruments that would help change the behaviour of land users while minimising adverse repercussions on their livelihoods. Findings showed that some developing tropical countries have recently been through a forest transition, thus shifting from declining to expanding forests at a national scale. However, in most of these (e.g. Vietnam), a significant part of the recent increase in national forest cover is associated with an increase in importation of food and timber products from abroad, representing leakage of carbon stocks across international borders. Avoiding deforestation and restoring forests will require a mixture of regulatory approaches, emerging market-based instruments, suasive options, and hybrid management measures. Policy analysis and modelling work showed the high degree of complexity at local levels and highlighted the need to take this heterogeneity into account—it is unlikely that there will be a one size fits all approach to make Reducing Emissions from Deforestation and Degradation (REDD+) work. Significant progress was made in the quantification of carbon and greenhouse gas (GHG) fluxes following land-use change in the tropics, contributing to narrower confidence intervals on peat-based emissions and their reporting standards. There are indications that there is only a short and relatively small window of opportunity of making REDD+ work—these included the fact that forest-related emissions as a fraction of total global GHG emissions have been decreasing over time due to the increase in fossil fuel emissions, and that the cost efficiency of REDD+ may be much less than originally thought due to the need to factor in safeguard costs, transaction costs and monitoring costs. Nevertheless, REDD+ has raised global awareness of the world’s forests and the factors affecting them, and future developments should contribute to the emergence of new landscape-based approaches to protecting a wider range of ecosystem services.  相似文献   

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