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1.
The extension of rotation lengths in forests has been proposed as an option for increasing carbon storage and contributing to climate change mitigation. This paper presents the results of a case study conducted on forests located in the southwest of France. The aim of this research was to assess the cost effectiveness of a subsidy/tax system on carbon fluxes. First, it is shown that such a mechanism leads forest owners to extend rotation lengths. However, cost effectiveness analysis shows that: (1) marginal social costs are more expensive than the private marginal costs of carbon sequestration; (2) marginal costs are higher when carbon stocks are discounted, ranging from 170.1 €/tC to 719.8 €/tC with discounted carbon stocks; and from 38.8 €/tC to 78.4 €/tC with undiscounted carbon stocks; (3) marginal costs are in the range of measures of the social value of carbon for France; (4) marginal costs increase with timber prices and increase with discount rate.  相似文献   

2.
Investments in agricultural research and development (R&D) made over the next few decades will likely prove critical in offsetting adverse climate change impacts on the global food system. In this study, we offer cost estimates of public R&D-led adaptation to climate change grounded in an explicit framework relating the flow of annual R&D expenditures to building knowledge capital and thereby raising productivity in agriculture. Our research uses a comprehensive collection of historical public agricultural R&D expenditure and a literature review of elasticity estimates linking knowledge stocks to agricultural productivity growth for key world regions. Given climate-driven crop yield projections generated from extreme combinations of crop and global circulation models, we find that offsetting crop yield losses projected by climate and crop models over 2006–2050 would require increased R&D adaptation investments of between $187 billion and $1,384 billion (in 2005 $PPP) if we invest between 2020 and 2040. This is 16–118% higher than global R&D investment if present spending trends continue. Although these costs are significant, worldwide R&D-led climate adaptation could offer favorable economic returns. Moreover, R&D-led adaptation could deliver gains in food security and environmental sustainability by mitigating food price increases and slowing cropland expansion.  相似文献   

3.
We analyse current and possible future reforms of the Indian food policies for the most important staple grains, wheat and rice, within a two‐commodity dynamic partial equilibrium model with stochastic shocks. The model is empirically grounded and reproduces past values well. It uses a new reduced‐form approach to capture private storage dynamics. We evaluate the implementation of the National Food Security Act (NFSA) under several policy measures with the current regime as well as two scenarios with a regime change – implementation of cash transfers and deficiency payments. Implications for market fundamentals and fiscal costs are simulated in the medium term – until 2020/21. The NFSA puts a high pressure on fiscal costs and public stocks. Relying on imports with low support prices results in low fiscal costs and stable, but higher domestic and international prices, and a high risk of zero stocks. A policy strategy to manipulate procurement prices in order to maintain public stocks close to the norms leads to slightly higher fiscal costs with lower, but more volatile prices. The highest domestic price volatility occurs under a strategy which uses export bans in order to maintain sufficient public stocks. A cash‐based regime can bring considerable savings and curb fiscal costs, particularly if targeted to the poor, and would leave sufficient stocks due to higher private stocks.  相似文献   

4.
The management of forests to store carbon and mitigate climate change has received significant international attention during the last decade. Using in situ data from a 2008–2009 forest inventory field campaign in Sri Lanka, this study describes the structural characteristics and carbon stocks of six natural forest types. This paper has a dual scope: i) to highlight the variation in carbon stored in aboveground biomass within and between forest types and ii) to determine the implications of the allometric equations chosen to calculate biomass carbon stocks. This study concerns work related to climate change interventions, such as Reducing Emissions from Deforestation and Forest Degradation (REDD+) and other forest-related, performance-based initiatives that require proper monitoring, reporting, and verification of carbon stocks, sinks and emissions. The results revealed that forests are heterogeneous in terms of tree density and height–diameter relationships, both between and within the six forest types investigated. The mean aboveground carbon stock in the different forest types ranged from 22 to 181 Mg C ha−1, and there were statistically significant differences in the carbon stocks of the six forest types in 7 of 15 cases. The estimated carbon stock depended heavily on the allometric equation used for the calculations, the variables, and its application to the specific life zone. Due to the diversity of forest structures, these results suggest that caution should be taken when applying default values to estimate forest carbon stocks and emission values in reporting and accounting schemes. The results also indicated the need for allometric equations that are context-specific for different forest types. Therefore, new field investigations and measurements are needed to determine these specific allometric equations, as well as the potential variation in forest carbon stocks in tropical natural forests.  相似文献   

5.
The dynamic duality econometric approach with the case of multiple outputs is applied to the US cigarette manufacturing industry to test for the presence of adjustment costs and quasifixed inputs with regard to stocks of capital and tobacco. Capital and tobacco stocks are found to be quasi-fixed inputs and the empirical results indicate that there are significant adjustment costs associated with adjusting these inputs. Short- and long-run own- and cross-price elasticities of factor demands are estimated for domestic and imported tobaccoes, materials, tobacco stocks, and capital. Output demand elasticities are also estimated. The two outputs, cigarettes produced for export and for the US market, are examined for equality of marginal costs. No evidence of differences in marginal costs was found. There is evidence that government restrictions on advertising have negative effects on output demand.  相似文献   

6.
This article evaluates irrigated agriculture sector response and resultant economic impacts of climate change for a part of the Murray Darling Basin in Australia. A water balance model is used to predict reduced basin inflows for mild, moderate and severe climate change scenarios involving 1, 2 and 4°C warming, and predict 13, 38 and 63% reduced inflows. Impact on irrigated agricultural production and profitability are estimated with a mathematical programming model using a two‐stage approach that simultaneously estimates short and long‐run adjustments. The model accounts for a range of adaptive responses including: deficit irrigation, temporarily following of some areas, permanently reducing the irrigated area and changing the mix of crops. The results suggest that relatively low cost adaptation strategies are available for a moderate reduction in water availability and thus costs of such a reduction are likely to be relatively small. In more severe climate change scenarios greater costs are estimated. Adaptations predicted include a reduction in total area irrigated and investments in efficient irrigation. A shift away from perennial to annual crops is also predicted as the latter can be managed more profitably when water allocations in some years are very low.  相似文献   

7.
Climate change is likely to have substantial effects on irrigated agriculture. Extreme climate events, such as droughts, are likely to become more common. These patterns are evident in median projections of climate change for the Murray–Darling Basin in Australia. Understanding climate change effects on returns from irrigation involves explicit representation of spatial changes in natural stocks (i.e., water supply) and their temporal variability (i.e., frequency of drought states of nature) and the active management responses to capital stocks represented by mitigation and alternative adaptation strategies by state of nature. A change in the frequency of drought will induce a change in the allocation of land and water between productive activities. In this paper, a simulation model of state-contingent production is used to analyze the effects of climate change adaptation and mitigation. In the absence of mitigation, climate change will have severe adverse effects on irrigated agriculture in the Basin. However, a combination of climate mitigation and adaptation through changes in land and water use will allow the maintenance of agricultural water use and environmental flows. Le changement climatique risque d’avoir des répercussions considérables sur l’agriculture irriguée. Les phénomènes climatiques extrêmes, tels que les sécheresses, risquent de devenir plus fréquents. Ces phénomènes sont mis en évidence dans les projections médianes du changement climatique établies pour le bassin de Murray–Darling, en Australie. Pour comprendre les répercussions du changement climatique sur le rendement des cultures irriguées, il faut disposer d’une représentation explicite des changements spatiaux qui touchent les stocks naturels (c.-à-d. l’approvisionnement en eau) et de leur variabilité temporelle (c.-à-d. les états de la nature de la fréquence de la sécheresse) et assurer une gestion active des stocks de capital grâce à des stratégies d’atténuation et d’adaptation selon l’état de la nature. Une variation de la fréquence des sécheresses entraînera une modification de l’allocation des terres et de l’eau entre les activités de production. Dans le présent article, nous avons utilisé un modèle de simulation états-contingences pour analyser les répercussions des stratégies d’atténuation du changement climatique et d’adaptation à ce changement. En l’absence de stratégies d’atténuation, le changement climatique aura des répercussions défavorables sur l’agriculture irriguée dans le Bassin. Toutefois, des stratégies d’atténuation combinées à des stratégies d’adaptation comprenant des changements dans l’utilisation des terres et de l’eau permettront de maintenir l’utilisation de l’eau à des fins agricoles et les débits environnementaux.  相似文献   

8.
This paper investigates the feasibility of changes in cropland-use as an adaptation strategy to minimise the economy-wide costs of climate change on agriculture. Nepal makes an interesting case study as it is one of the most vulnerable agricultural economies within South Asia. We develop a comparative static multi-household computable general equilibrium (CGE) model for Nepal, with a nested set of constant elasticity of transformation (CET) functional forms, to model the allocation of land within different agricultural sectors. Land transformation elasticities in these CET functions are allowed to reflect the ease of switching from one crop to another based on their agronomic characteristics. The results suggest that, in the long run, farmers in Nepal tend to allocate land to crops that are comparatively less impacted by climate change, such as paddy, thereby minimising the economy-wide impacts of climate change. Furthermore, the results reveal that land-use change tends to reduce the income disparity between different household groups by significantly moderating the income losses of marginal farmers. Therefore, it is suggested that policy makers in Nepal should prioritise schemes such as providing climate-smart paddy varieties (i.e., those that are resistant to heat, drought and floods) to farmers, subsidising fertilizers, improving agronomic practices, and educating farmers to switch from crops that are highly impacted by climate change to those that are not, such as paddy.  相似文献   

9.
Land use changes and forests both play an important role in combating climate change. The climate effects of forest land consolidation have, however, not been studied in detail. As such, this study identifies a number of possible climate effects of forest land consolidation. To specify these, the increased carbon storage in the Pahkakoski land consolidation project (Finland) due to increased forest growth is valued through substitution costs. The results show that the value of the increased carbon storage in the project area is approximately 750 000 euros, or €153/ha. This emanates from the increased growth due to remedial drainage and from the increased forested area. The result is, however, sensitive to changes in the shadow price of carbon. Likewise, the study recognises a need for studies concerning the total climate effect of measures, such as remedial drainage that may also release carbon from the ground. While the overall effects of forest land consolidation are difficult to estimate with current knowledge, this article highlights the potential of land consolidation to combat climate change.  相似文献   

10.
Stabilization of prices is an important element of food policy in India as in most other countries — both developing and eveloped. However, since the magnitude of grain stocks held for this purpose as well as the costs of physical storage have become prohibitively high, there is now a need for finding cost-effective alternatives including non interventionist and market-oriented methods for price stabilization. In this paper we consider the case of rice and wheat which are staple foodgrains in India. We make a comparison between alternative price stabilization policies including that of holding buffer stocks in terms of their impact on domestic price stability, producer and consumer welfare and government costs. A multi-market equilibrium framework is used where private storage, consumption, supply and prices of rice and wheat are determined simultaneously. Indian exports and imports are assumed to affect world prices. The alternative price stabilizing mechanisms are ranked according to both the criteria, welfare and price stability achieved. The main findings are as follows. The ranking of alternatives varies with the criterion used. Greater price stability need not necessarily imply greater welfare. The option of variable levies on private external trade turns out to be the most inexpensive and that of domestic buffer stocks the costliest in achieving price stability. Further, the efficacy of buffer stocks and subsidy to private storage in stabilizing prices is lower under free trade as compared to the case where the economy is closed to private external trade.  相似文献   

11.
Relative agricultural productivity shocks emerging from climate change will alter regional cropland use. Land allocations are sensitive to crop profits that in turn depend on yield effects induced by changes in climate and technology. We develop and apply an integrated framework to assess the impact of climate change on agricultural productivity and land use for the U.S. Northern Great Plains. Crop-specific yield–weather models reveal crop comparative advantage due to differential yield impacts of weather across the region's major crops, that is, alfalfa, wheat, soybeans, and maize. We define crop profits as a function of the weather-driven yields, which are then used to model land use allocation decisions. This ultimately allows us to simulate the impact of climate change under the RCP4.5 emissions scenario on land allocated to the region's major crops as well as to grass/pasture. Upon removing the trends effects in yields, climate change is projected to lower yields by 33–64% over 2031–2055 relative to 1981–2005, with soybean being the least and alfalfa the most affected crops. Yield projections applied to the land use model at present-day input costs and output prices reveals that Dakotas’ grass acreage will increase by up to 23%, displacing croplands. Wheat acreage is expected to increase by up to 54% in select southeastern counties of North Dakota and South Dakota, where maize/soy acreage had increased by up to 58% during 1995–2016.  相似文献   

12.
To reduce agricultural greenhouse gas (GHG) emissions, farmers need to change current farming practices. However, farmers' climate change mitigation behaviour and particularly the role of social and individual characteristics remains poorly understood. Using an agent-based modelling approach, we investigate how knowledge exchange within farmers' social networks affects the adoption of mitigation measures and the effectiveness of a payment per ton of GHG emissions abated. Our simulations are based on census, survey and interview data for 49 Swiss dairy and cattle farms to simulate the effect of social networks on overall GHG reduction and marginal abatement costs. We find that considering social networks increases overall reduction of GHG emissions by 45% at a given payment of 120 Swiss Francs (CHF) per ton of reduced GHG emissions. The per ton payment would have to increase by 380 CHF (i.e., 500 CHF/tCO2eq) to reach the same overall GHG reduction level without any social network effects. Moreover, marginal abatement costs for emissions are lower when farmers exchange relevant knowledge through social networks. The effectiveness of policy incentives aiming at agricultural climate change mitigation can hence be improved by simultaneously supporting knowledge exchange and opportunities of social learning in farming communities.  相似文献   

13.
Reducing emissions from deforestation and forest degradation, conservation and sustainable management of forests and enhancement of forest carbon (REDD+) are considered to be important cost effective approaches for global climate change mitigation; therefore, such practices are evolving as the REDD+ payment mechanism in developing countries. Using six years (2006–2012) data, this paper analyses trade-offs between carbon stock gains and the costs incurred by communities in generating additional carbon in 105 REDD+ pilot community forests in Nepal. It estimates foregone benefits for communities engaged in increasing carbon stocks in various dominant vegetation types. At recent carbon and commodity prices, communities receive on average US$ 0.47/ha/year of carbon benefits with the additional cost of US$ 67.30/ha/year. One dollar’s worth of community cost resulted 0.23 Mg of carbon sequestration. Therefore, carbon payment alone may not be an attractive incentive within small-scale community forestry and should link with payments for ecosystem services. Moreover, the study found highest community sacrificed benefits in Shorea mixed broadleaf forests and lowest in Schima-Castanopsis forests, while carbon benefits were highest in Pine forests followed by Schima-Castanopsis forests and lowest in Rhododendron-Quercus forests. This indicates that costs and benefits may vary by vegetation type. A policy should consider payment for other environmental services, carbon gains, co-benefits and trade off while designing the REDD+ mechanism in community based forest land use practice with equitable community outcomes. The learning from this study will help in the formulation of an appropriate REDD+ policy for community forestry.  相似文献   

14.
The efficiency of potential climate change mitigation is predicated on future costs and benefits and thus heavily influenced by the discount scheme. Dual discounting involves discounting carbon and monetary values differently; stand level modeling efforts show that it improves the profitability of afforestation projects. However, these stand level results may not hold across other age classes and stocking levels. Using a partial, spatial equilibrium model of the Norwegian forest sector, we analyze the impacts of a dual discounting scheme on climate change mitigation efforts. Dual discounting results in less mitigation efforts in the first decades but substantially higher long-term mitigation efforts.  相似文献   

15.
The purpose of this paper is to calculate the value of stochastic carbon sequestration in climate change mitigation when also carbon dioxide emissions from fossil fuels and abatement costs are stochastic. The replacement cost method is used where the value of carbon sink is calculated as associated cost savings from replacement of more expensive mitigation options for achieving a given emission target. Minimum costs with and without carbon sinks are derived with a safety-first approach in a chance constrained programming framework which also accounts for variability in control costs. The theoretical results show that for high enough risk discount, carbon sink is not included in a cost effective mitigation program even when the carbon sink cost is zero. The empirical application to the EU independent commitment of 20% reduction in carbon dioxides shows large variation in carbon sink value depending on risk discount. Under no uncertainty, the value can correspond to 0.33% of total GDP in EU, but it declines due to the uncertainty associated with forest carbon sink and is zero for high probability levels in achieving the target. Thus, whether or not to recommend the inclusion of carbon sink in the EU climate policy depends on the uncertainty of carbon sinks in relation to other sources and on the importance of reaching stipulated emission reduction targets.  相似文献   

16.
Irrigation expansion is critical to increase crop yields and mitigate effects from climate change in Sub‐Saharan Africa, but the low profitability has led to little irrigation investments in the region so far. Using an integrated modeling framework, we simultaneously evaluate the returns to irrigation arising from both economic and biophysical impact channels to understand what determines the profitability of irrigation in Malawi. Our results confirm that the returns to irrigation cannot cover the costs in Malawi. While labor‐intensive irrigation expansion leads to unfavorable structural change in the short‐run, the profitability hinges on low irrigated yields that fall far from expectations due to insufficient input use and crop management techniques. On the other hand, we find that the nonmonetary benefits of irrigation regarding higher food security, lower poverty, and reduced vulnerability to climate change make investments in irrigation worthwhile to improve the livelihoods of smallholders.  相似文献   

17.
Following the approach of Berndt, Fuss, and Waverman, a dynamic model for U.S. cigarette manufacturing is developed and factor demands estimated. Tobacco and capital stocks are treated as quasi-tixed inputs. The results indicate that there are significant adjustment costs associated with adjusting tobacco stocks, but not with adjusting the capital stock. Short-run, intermediate-run, and long-run output constant elasticities are estimated for inputs in cigarette production. Demand for U.S. tobacco by U.S. cigarette manufacturers is found be more inelastic than shown by previous studies using static models. Cigarettes produced for export appear to differ in their marginal cost of production from cigarettes produced for the sale in the U.S. market.  相似文献   

18.
This paper evaluates the role of trade liberalization and agricultural intensification in mitigating climate change cause and effects on land use and emissions using a computable general equilibrium model. Our results indicate that cropland expansion triggered by climate-induced crop productivity changes results in deforestation and increases emissions in South Asia and globally. Global full trade liberalization on all goods is the optimum policy for South Asia despite significant global deforestation, but for the world, unilateral partial trade liberalization on all goods is a more appropriate policy while ensuring a considerable emissions reduction for South Asia. These results indicate that mitigation responses to climate change are location specific and no one trade policy is suitable at the regional and global levels. Lastly, agricultural intensification by improving productivity growth is the best strategy in land-based emissions mitigation, thereby avoiding the transformation of forest and pasture lands for agricultural cultivation both at regional and global levels.  相似文献   

19.
Broadacre agriculture is a major emitter of greenhouse gases (GHG). To improve efficiency of climate change policies, we need to know the marginal abatement costs of agricultural GHG. This article combines calculations of on‐farm GHG emissions with an input‐based distance function approach to estimate the marginal abatement costs for a broadacre farming system in the Great Southern Region of Western Australia. The results show that, in the study region, the average marginal abatement cost for the 1998–2005 periods was $29.3 per tonne CO2‐e. Farms with higher crop output shares were found to have higher marginal abatement costs. Overall, our results indicate that broadacre agriculture is among the lowest cost sources of GHG mitigation.  相似文献   

20.
Carbon-accounting methods and reforestation incentives   总被引:2,自引:0,他引:2  
The emission of greenhouse gases, particularly carbon dioxide, and the consequent potential for climate change are the focus of increasing international concern. Temporary land-use change and forestry projects (LUCF) can be implemented to offset permanent emissions of carbon dioxide from the energy sector. Several approaches to accounting for carbon sequestration in LUCF projects have been proposed. In the present paper, the economic implications of adopting four of these approaches are evaluated in a normative context. The analysis is based on simulation of Australian farm–forestry systems. Results are interpreted from the standpoint of both investors and landholders. The role of baselines and transaction costs are discussed.  相似文献   

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