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1.
We analyze the long‐term impacts of large‐scale expansion of biofuels on land‐use change, food supply and prices, and the overall economy in various countries or regions using a multi‐country, multi‐sector global computable general equilibrium model augmented with an explicit land‐use module and detailed biofuel sectors. We find that an expansion of biofuel production to meet the existing or even higher targets in various countries would slightly reduce GDP at the global level but with mixed effects across countries or regions. Significant land re‐allocation would take place with notable decreases in forest and pasture lands in a few countries. The expansion of biofuels would cause a moderate decrease in world food supply and more significant decreases in developing countries like India and Sub‐Saharan Africa. Feedstock commodities (sugar, corn and oil seeds) would experience significant increases in their prices in 2020, but other price changes are small.  相似文献   

2.
Being the two largest ethanol producers in the world, biofuel policies in Brazil and the United States affect both their domestic markets and the global food and biofuel economy. In this article we develop a price endogenous mathematical programming model to simulate and analyze the impacts of biofuel mandates and trade distortions on land use, agricultural commodity and transportation fuel markets, and global environment. We find that an 80% increase in total biofuel production from its 103 billion liter baseline level to the mandated 183 billion liter level in 2022 can be achieved with less than 2% increase in total cropland use in both countries. In the United States, this would occur with cellulosic biofuels meeting nearly half of the biofuels consumed and produced largely on cropland pasture and corn ethanol meeting the rest of the mandate and resulting in a 2% increase in corn price. In Brazil, the expansion in sugarcane production would be achieved by reducing land under pasture and a marginal increase in intensification of livestock production. In the aggregate, biofuel policies increase economic surplus in both countries by 1% and redistribute the benefits from agricultural consumers to agricultural producers and the fuel sector. Finally, we also find that full implementation of the mandates in North America, China, and the European Union would reduce the global life‐cycle global greenhouse gas emissions by about 5%.  相似文献   

3.
Biofuels often raise the specter of food insecurity, water resource depletion, and greenhouse gas emissions from land clearing. These concerns underpin the “sustainability criteria” governing access to European biofuel markets. However, it is unclear if producing biofuels in low‐income countries does exacerbate poverty and food insecurity, and moreover, whether the sustainability criteria should apply to all agricultural exports entering European markets. We develop an integrated modeling framework to simultaneously assess the economic and environmental impacts of producing biofuels in Malawi. We incorporate the effects of land use change on crop water use, and the opportunity costs of using scarce resources for biofuels instead of other crops. We find that biofuel production reduces poverty and food insecurity by raising household incomes. Irrigated outgrower schemes, rather than estate farms, lead to better economic outcomes, fewer emissions, and similar water requirements. Nevertheless, to gain access to European markets, Malawi would need to reduce emissions from ethanol plants. We find that biofuels’ economic and emissions outcomes are generally preferable to tobacco or soybeans. We conclude that the sustainability criteria encourage more sustainable biofuel production in countries like Malawi, but are perhaps overly biased against biofuels since other export crops raise similar concerns about food security and environmental impacts.  相似文献   

4.
The rapid growth of biofuels production, particularly in the United States, the EU, and Brazil, has had important implications for the global livestock industry—both by raising the cost of feed grains and oilseeds and by forcing onto the market a large supply of biofuel by‐products, most of which end up in livestock feed rations. This article investigates the impact of an expanding biofuels industry on the mix and location of global livestock production. Surprisingly, we find that growth in the U.S. and EU biofuels industries results in larger absolute reductions in livestock production overseas than in those regions, due to the international transmission of grains prices which is offset locally by the lower cost of by‐products. We also find that nonruminant production is cut more than ruminant livestock, because it is less able to use biofuel by‐products in its feed rations. Implementing biofuel mandates increases cropland area, a large portion of which is estimated to come from reduced grazing lands. The biofuel producing regions are expected to reduce their coarse grains exports and increase imports of oilseeds and vegetable oils, while they increase their exports of processed feed materials. In sum, biofuel mandates have important consequences for livestock as well as crops, with net effects influenced by the important role of by‐products in substituting for feedstuffs.  相似文献   

5.
We propose a causal analysis framework to increase understanding of land-use change (LUC) and the reliability of LUC models. This health-sciences-inspired framework can be applied to determine probable causes of LUC in the context of bioenergy. Calculations of net greenhouse gas (GHG) emissions for LUC associated with biofuel production are critical in determining whether a fuel qualifies as a biofuel or advanced biofuel category under regional (EU), national (US, UK), and state (California) regulations. Biofuel policymakers and scientists continue to discuss to what extent presumed indirect land-use change (ILUC) estimates should be included in GHG accounting for biofuel pathways. Current estimates of ILUC for bioenergy rely largely on economic simulation models that focus on causal pathways involving global commodity trade and use coarse land-cover data with simple land classification systems. This paper challenges the application of such models to estimate global areas of LUC in the absence of causal analysis. The proposed causal analysis framework begins with a definition of the change that has occurred and proceeds to a strength-of-evidence approach that includes plausibility of relationship, completeness of causal pathway, spatial co-occurrence, time order, analogous agents, simulation model results, and quantitative agent–response relationships. We discuss how LUC may be allocated among probable causes for policy purposes and how the application of the framework has the potential to increase the validity of LUC models and resolve controversies about ILUC, such as deforestation, and biofuels.  相似文献   

6.
OECD countries’ biofuels policies, derived from energy and environmental legislation and activated by high oil prices, were the primary cause of not only the sudden spike in grain and oilseed prices in 2007–2008 but also of the ensuing price volatility. Even though developing countries have a comparative advantage in biofuels production, they were shut out of rich countries’ biofuel markets by trade discriminating biofuels policies. Developing countries would not have been able to take full advantage of the price spike in the short run anyway given the low supply elasticities and the long time required for biofuel production to come online, unlike for corn‐ethanol. The controversy over the right price of food is misplaced and policy makers should instead focus on improving biofuels policies, which like their counterpart agricultural policies in previous decades, have damaged the welfare of developing countries.  相似文献   

7.
This paper reviews the relationships between land use and climate change. It explores how land use decisions will be affected by future changes in the climate, but also the feedbacks from land use change to the global climate system through greenhouse gas (GHG) fluxes. Past changes in land use were characterised by decreasing areas of agricultural use and increasing areas of forested and urbanised land. This has led to UK land use being a net sink for GHGs, mostly due to forestation. However, existing forests have on average passed their age for maximum net removals of carbon from the atmosphere. In the next decade at least, net removals from UK forests are likely to decrease significantly.Longer term scenarios of future land use change are consistent in their expectation of further declines in the agricultural area used for food production – offset to some extent by increased bioenergy cropping – along with increases in forested and urban areas. These trends are broadly consistent with the observed past land use change, but are calculated from various assumptions about future changes in drivers rather than by extrapolation from the past. Socio-economic and technological changes are likely to be the most important drivers for land use, with climate change having a smaller influence. The land use changes represented in these scenarios would likely reduce GHG emissions and enhance carbon sinks. These trends would be reinforced by small future changes in the climate, but large climatic changes are likely to cause net GHG fluxes to switch from being a sink to a source. Land use change will also be moderated by potential policy goals that seek to reduce GHG emissions from land and/or increase the size of land-based sinks. This includes strategies to reduce carbon and nitrogen emissions through increased efficiency, afforestation and biofuel production.  相似文献   

8.
Sweetness and Power – Public Policies and the ‘Biofuels Frenzy’ In the last decade, there has been a huge policy‐led expansion in biofuels production and consumption. This paper presents some of the findings of a funded research project which has sought to identify the drivers of biofuels policies over this period. It focuses on the EU, US and Brazil which, together, represent about 90 per cent of global biofuels markets. Biofuels policies have three key drivers: as a partial substitute for fossil fuels, to lower greenhouse gas emissions; as a way of improving energy security, by diversifying away from fossil fuels and from the limited number of countries with fossil‐fuel reserves; and as a means of promoting rural development, given the opportunities offered by the production of biofuel feedstocks and their processing into biofuels. One particular challenge for both the EU and US has been to create and sustain a broad coalition of stakeholder interests in support of biofuels and biofuel policies. Both have sought to promote ‘conventional’ biofuels now, whilst trying to aid the development of ‘advanced’ biofuels industries that will address problems with existing technologies. The continued failure to deliver significant quantities of advanced biofuels raises questions for biofuels policymakers going forward, not least dealing with the downsides of conventional biofuels that, so far, have not been mitigated by a successful transition to advanced biofuels.  相似文献   

9.
Agricultural activities are a substantial contributor to global greenhouse gas (GHG) emissions, accounting for about 58% of the world's anthropogenic non‐carbon dioxide GHG emissions and 14% of all anthropogenic GHG emissions, and agriculture is often viewed as a potential source of relatively low‐cost emissions reductions. We estimate the costs of GHG mitigation for 36 world agricultural regions for the 2000–2020 period, taking into account net GHG reductions, yield effects, livestock productivity effects, commodity prices, labor requirements, and capital costs where appropriate. For croplands and rice cultivation, we use biophysical, process‐based models (DAYCENT and DNDC) to capture the net GHG and yield effects of baseline and mitigation scenarios for different world regions. For the livestock sector, we use information from the literature on key mitigation options and apply the mitigation options to emission baselines compiled by EPA.  相似文献   

10.
Biofuel policies (blend mandate or tax credit) have impacts on food and energy prices, and on land-use. The magnitude of these effects depends on the market response to price, and thus on the agricultural supply curve, which, in turn, depends on the land availability (quantity and agronomic quality) and relative prices. To understand these relationships, we develop a theoretical framework with an explicit representation of land heterogeneity. The elasticity of the supply curve is shown to be non-constant, depending on land heterogeneity and the availability of land for agricultural expansion. This influences the welfare economics of biofuels policies, and the possible carbon leakage in land and fuel markets. We emphasize that the impacts of biofuel policies on welfare and land-use change depend strongly on the potential development of the agricultural sector in terms of expansion and intensification, and not only on its current size.  相似文献   

11.
The impacts of climate change on agriculture in developing countries will depend on the extent to which agricultural production in those regions adapts to climate change’s influences. This study uses a whole-farm land use optimisation approach to explore climate change impacts, when including adaptation, on farm profitability, production and associated greenhouse gas (GHG) emissions in the Loess Plateau of northern China. The results show that with adaptation activities, the losses in smallholder farm profitability caused by the climate change could be moderate. Declining rainfall results in land use changes that generate higher on-farm GHG emissions with the most economically beneficial adaptations. With 5 % or 10 % decline in annual rainfall, the introduction of agricultural carbon tax would generate substantial reduction in on-farm GHG emissions. With 30 % rainfall reduction, agricultural carbon tax is not likely to bring about considerable emission reduction. The economically optimised land uses are generally sensitive to potential changes. When rainfall reductions appear, there is a clear trend toward reducing cropping area and transiting to pasture. With 5–10% rainfall reductions, increasing agricultural carbon tax with same rainfall reduction leads to the expansion in cropping enterprises. However, with 30 % rainfall reduction, land allocations are not sensitive to agricultural carbon tax. When with declining annual rainfall, in the optimal enterprises more oats-pasture rotations are employed to reduce wheat dominated rotations. Besides land use patterns, adaptations through altering farm management practices are also necessary. The economically optimised sheep flock would be increased considerably with declining rainfall. Overall, policymakers are suggested to initial more educational schemes to tell smallholder farmers how to make the best use of available adaptation strategies and consider changes in climate when design and implement agricultural policy.  相似文献   

12.
Integrated Assessment studies have shown that meeting ambitious greenhouse gas mitigation targets will require substantial amounts of bioenergy as part of the future energy mix. In the course of the Agricultural Model Intercomparison and Improvement Project (AgMIP), five global agro‐economic models were used to analyze a future scenario with global demand for ligno‐cellulosic bioenergy rising to about 100 ExaJoule in 2050. From this exercise a tentative conclusion can be drawn that ambitious climate change mitigation need not drive up global food prices much, if the extra land required for bioenergy production is accessible or if the feedstock, for example, from forests, does not directly compete for agricultural land. Agricultural price effects across models by the year 2050 from high bioenergy demand in an ambitious mitigation scenario appear to be much smaller (+5% average across models) than from direct climate impacts on crop yields in a high‐emission scenario (+25% average across models). However, potential future scarcities of water and nutrients, policy‐induced restrictions on agricultural land expansion, as well as potential welfare losses have not been specifically looked at in this exercise.  相似文献   

13.
This article is divided into three parts. First, it provides an overview of the main outcomes of the last IPCC assessment report, both in terms of economic drivers of greenhouse gas (GHG) emissions, and in terms of impacts of climate change, in particular for the agriculture sector. Then, it focuses on policy options and their optimal design, taking into account technological availability, international cooperation, and above all the stringency of the remaining carbon budget. Finally, it analyzes the size and direction of investment decisions required to stabilize GHG emissions and their implications for economic development.  相似文献   

14.
Land is a scarce resource affecting the implementation of many sectoral policies. In Indonesia, the expansion of palm oil plantations has led to non-sustainable land use practices in past years, particularly deforestation. More recently, the government has set ambitious targets for the adoption of biodiesel which will require expansion of oil palm plantations, thus putting further pressure on land. Meanwhile, the need to guarantee food supply, forest conservation and climate change mitigation also imply challenges when it comes to land allocation and use. This paper examines the role that land plays in the implementation of sectoral policies in Indonesia, exploring the availability of land to satisfy the multiple goals defined in national policies. We explore land competition resulting from allocations made in official policy documents starting with biofuel policy. The analysis of policy goals and coherence when it comes to land allocation is made in relation to agriculture, climate and forestry policies. We conclude that adjustments need to be made in the policies to avoid overlappings and misinterpretations when it comes to land allocation. The area made available for meeting each sectoral policy goal when taking into account cross sectoral interactions is: 14.2 Mha for agriculture, 43 Mha for climate mitigation measures, 9.2 Mha for forestry, and 20.9 Mha for biofuels. A more uniform land classification and development of a common reference database will increase transparency on land allocation and use, and help to monitor land use change, ultimately supporting the achievement of multiple national goals.  相似文献   

15.
African countries continue to face deepening food crises that have been accentuated by the global food, energy, and financial crises. This situation is part of a long‐term structural problem: decades of under‐investments in agricultural sector and poor policies of support for smallholder farmers who form the bulk of the farming population. The inability of these farmers to achieve a supply response when commodity prices were high and market access was less of a problem suggests that there are multiple sets of binding constraints that continue to limit the potential of agricultural growth to reduce food security and poverty on the continent. This article reviews some of the historical trends that have hampered the performance of the agriculture sector. In addition, it reviews the impacts of more positive trends that could stimulate agricultural growth in Africa that could change the African agricultural landscape. The article however warns that there are more recent global developments and some continental challenges that could prevent or slow agricultural growth. These include the global financial crisis, public sector investments, inequities in global agricultural development policies, rush for agricultural lands by foreign investors, domestic commercial financing markets, climate change, and emerging carbon markets. The article argues that while opportunities for accelerated growth exists for African agriculture, new sets of policy instruments will be needed to support smallholder farmers to access new agricultural technologies, finance, reduce impacts of climate change, and adopt sustainable land use practices that can allow them to benefit from emerging global carbon markets.  相似文献   

16.
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   

17.
In many countries, the biofuels sector was encouraged to expand its activities supported by public policies incentives, especially to achieve improvements in energy security and to reduce greenhouse gas (GHG) emission. The Brazilian government followed these initiatives and undertook some responsibilities against the international scenario related to climate change. One of the theses commitments concerning actions to reduce the GEE emissions by some 37% by 2020. The Sugarcane Agroecology Zoning provides technical subside to policy makers to direct sugarcane expansion to permitted areas and a sustainable production in Brazil and is considered a guideline to sustainable sugarcane production in Brazil. However, although aiming at a sustainable production, the zoning only considered natural aspects of the country, as soils and climate and an approach that consider all the dimensions of the sustainability is still missing. Hence, this paper aims to propose a framework to evaluate biofuel sustainability to support public policies, especially concerning improvements in Brazilian decision-supporting tools.  相似文献   

18.
We investigate the economic feasibility of bioelectricity production from biomass in Malaysia and its impact on greenhouse gas (GHG) emissions and storage, agricultural prices, agricultural employment and deforestation. For this purpose, we develop a partial equilibrium model that projects agricultural prices, production, imports, exports, domestic consumption and land use in 5‐year increments between 2015 and 2065. Our results show that by 2030 biomass‐generated electricity can supply 36.5 per cent of the electricity generated in Malaysia, 16 times more than the 2016 electricity supply from biomass. Increased bioelectricity production from biomass will significantly reduce GHG emissions and will help Malaysia meet its commitment in the Paris Agreement to mitigate GHG emission by 45 per cent before 2030. Our modelling shows that biomass‐generated electricity creates a derived demand for waste biomass that expands the area of oil palm plantations. The expansion lowers agricultural prices, boosts agricultural employment and leads to some deforestation as landowners clear rainforest to plant oil palm trees. Nonetheless, the deforestation does not increase GHG emissions since GHG gains from bioelectricity significantly exceed GHG losses from deforestation.  相似文献   

19.
‘Land grab’ has become a catch‐all phrase to refer to the current explosion of (trans)national commercial land transactions mainly revolving around the production and export of food, animal feed, biofuels, timber and minerals. Two key dimensions of the current land grab – namely, the politics of changes in land use and property relations change (and the links between them) – are not sufficiently explored in the current literature. We attempt to address this gap by offering a preliminary analysis through an analytical approach that suggests some typologies as a step towards a fuller and better understanding of the politics of global land grabbing.  相似文献   

20.
Agricultural economics is at the nexus of the major policy options surrounding the global bio‐economy. The outputs from agriculture have expanded beyond the traditional food, feed, and fiber to include fuel and other nonfood applications as well as environmental goods due to recent technological developments and changing consumer demands. Numerous policy questions have arisen within the bio‐economy. This article introduces and summarizes several invited panel sessions on issues of special importance in the global bio‐economy: new institutions of dealing with uncertainty and increased volatility related to climate change; structural transformations in agricultural production and food consumption and their effect on development; biofuel policies and development; and determinants of changes in consumer attitudes to new products and technologies.  相似文献   

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