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1.
Current practices for estimating indirect land use change (iLUC) due to United States biofuel production rely on assumption-heavy, global economic modeling approaches. Prior iLUC studies have failed to compare their predictions to past global historical data. An empirical approach is used to detect evidence for iLUC that might be catalyzed by United States biofuel production through a “bottom-up”, data-driven, statistical approach. Results show that biofuel production in the United States from 2002 to 2007 is not significantly correlated with changes in croplands for corn (coarse grain) plus soybean in regions of the world which are corn (coarse grain) and soybean trading partners of the United States. The results may be interpreted in at least two different ways: 1) biofuel production in the United States through 2007 (the last date for which information is available) probably has not induced any indirect land use change, and 2) this empirical approach may not be sensitive enough to detect indirect land use change from the historical data. It seems clear that additional effort may be required to develop methodologies to observe indirect land use change from the historical data. Such efforts might reduce uncertainties in indirect land use change estimates or perhaps form the basis for better policies or standards for biofuels.  相似文献   

2.
This study looks at the land use impact of the biofuels expansion on both the intensive and extensive margin, and its environmental consequences. We link economic, geographical and environmental models by using spatially explicit common units of analysis and use remote sensing crop cover maps and digitized soils data as inputs. Land use changes are predicted via economic analysis of crop rotation choice and tillage under alternative crop prices, and the Environmental Policy Integrated Climate (EPIC) model is used to predict corresponding environmental impacts. The study focuses on Iowa, which is the leading biofuels hotspot in the U.S. due to intensive corn production and the high concentration of ethanol plants that comprise 28% of total U.S. production. We consider the impact of the biofuels industry both on current cropland and on land in the Conservation Reserve Program (CRP), a land set-aside program. We find that substantial shifts in rotations favoring continuous corn rotations are likely if high corn prices are sustained. This is consistent with larger scale analyses which show a shift of the current soybean production out of the Corn Belt. We find that sediment losses increase substantially on the intensive margin, while nitrogen losses increase less. Returning CRP land into production has a vastly disproportionate environmental impact, as non-cropped land shows much higher negative marginal environmental effects when brought back to row crop production. This illustrates the importance of differentiating between the intensive and extensive margin when assessing the expansion of biofuel production.  相似文献   

3.
Second-generation bioenergy crops, including Short Rotation Forestry (SRF), have the potential to contribute to greenhouse gas (GHG) emissions savings through reduced soil GHG fluxes and greater soil C sequestration. If we are to predict the magnitude of any such GHG benefits a better understanding is needed of the effect of land use change (LUC) on the underlying factors which regulate GHG fluxes. Under controlled conditions we measured soil GHG flux potentials, and associated soil physico-chemical and microbial community characteristics for a range of LUC transitions from grassland land uses to SRF. These involved ten broadleaved and seven coniferous transitions. Differences in GHGs and microbial community composition assessed by phospholipid fatty acids (PLFA) profiles were detected between land uses, with distinctions between broadleaved and coniferous tree species. Compared to grassland controls, CO2 flux, total PLFAs and fungal PLFAs (on a mass of C basis), were lower under coniferous species but unaffected under broadleaved tree species. There were no significant differences in N2O and CH4 flux rates between grassland, broadleaved and coniferous land uses, though both CH4 and N2O tended to have greater uptake under broadleaved species in the upper soil layer. Effect sizes of CO2 flux across LUC transitions were positively related with effect sizes of soil pH, total PLFA and fungal PLFA. These relationships between fluxes and microbial community suggest that LUC to SRF may drive change in soil respiration by altering the composition of the soil microbial community. These findings support that LUC to SRF for bioenergy can contribute towards C savings and GHG mitigation.  相似文献   

4.
In the Renewable Fuel Standard (RFS2) program, the United States Environmental Protection Agency (U.S. EPA) has used partial equilibrium models to estimate the overall indirect land use change (iLUC) associated with the biofuel scenario mandated by the Energy Independence and Security Act of 2007 (EISA). For regulatory purposes, the U.S. EPA “shocks” (changes) the amount of each biofuel in the economic models one at a time to estimate the threshold values for specific biofuels (single-shock analysis). The primary assumption in the single-shock analysis is that iLUC is a linear process with respect to biofuels, i.e., that interactions between different biofuels are trivially small. However, the assumption of linearity in the single-shock analysis is not appropriate for estimating the threshold values for specific biofuels when the interactions between different biofuels are not small.Numerical results from the RFS2 program show that the effects of interactions between different biofuels are too large to be ignored. Thus, the threshold values for specific biofuels determined by the U.S. EPA are scenario-dependent and value choice-driven. They do not reflect real impacts of specific biofuels. Using scenario-dependent values for regulation is arbitrary and inappropriate. Failure to deal appropriately with interactions between different biofuels when assigning iLUC values to specific biofuels is a mathematical and systematic flaw; it is not an “uncertainty” issue. The U.S. EPA should find better ways to differentiate the contribution of one biofuel versus another when assigning iLUC values or find better means of regulating the land use change impact of biofuel production.  相似文献   

5.
The objective of this paper is to evaluate the greenhouse gas (GHG) emissions impacts of the use of different alternative biofuels in passenger vehicles in Spain in order to meet EU biofuel goals. Different crop production alternatives are analysed, including the possible import of some raw materials. Availability of land for national production of the raw materials is analysed and indirect land use changes and associated GHG emissions are quantified.There are important differences in GHG emissions of biofuels depending on the raw material used and whether this is domestically produced or imported. Ethanol production using imported cereals and FAME production using domestic rapeseed have the highest GHG emissions per kilometre driven. Fatty acid methyl ester (FAME) production from sunflower has shown the lowest emissions. When taking into account the results of GHG emissions savings per hectare, these findings are somehow reversed. Production of ethanol and around 12% of FAME can be done domestically. The rest will need to be imported and will cause indirect land use change (ILUC). Therefore, ethanol production will not displace any land, whereas FAME production will displace some amounts of land. Calculated ILUC factors are 29%-34%. The additional GHG emissions due to these indirect land use changes are significant (67%-344% of life cycle GHG emissions).Standalone, the EU biofuel targets can have important benefits for Spain in terms of global warming emissions avoided. However, when considering the impact of land use change effects, these benefits are significantly reduced and can even be negative.  相似文献   

6.
Early comprehensive life cycle assessments (LCA’s) that compared biofuels with fossil fuels already appeared in the beginning of the eighties. Since then the public, scientific and political interest in biofuels has continuously grown and the number of biofuels and assessed parameters has increased.At the same time, the methodology for this type of assessment has improved with certain aspects of the approach having come up by and by a process which still continues today. Several issues related to the land use currently stand in the centre of expert discussions.  相似文献   

7.
To date, feedstock resource assessments have evaluated cellulosic and algal feedstocks independently, without consideration of demands for, and resource allocation to, each other. We assess potential land competition between algal and terrestrial feedstocks in the United States, and evaluate a scenario in which 41.5 × 109 L yr−1 of second-generation biofuels are produced on pastureland, the most likely land base where both feedstock types may be deployed. Under this scenario, open-pond microalgae production is projected to use 1.2 × 106 ha of private pastureland, while terrestrial biomass feedstocks would use 14.0 × 106 ha of private pastureland. A spatial meta-analysis indicates that potential competition for land under this scenario would be concentrated in 110 counties, containing 1.0 and 1.7 × 106 ha of algal and terrestrial dedicated feedstock production, respectively. A land competition index applied to these 110 counties suggests that 38 to 59 counties could experience competition for upwards of 40% of a county's pastureland, representing 2%–5% of total pastureland in the U.S.; therefore suggesting little overall competition between algae production, terrestrial energy feedstocks and alternative uses for existing agricultural production such as livestock grazing.  相似文献   

8.
Use of ethanol as a transportation fuel in the United States has grown from 76 dam3 in 1980 to over 40.1 hm3 in 2009 — and virtually all of it has been produced from corn. It has been debated whether using corn ethanol results in any energy and greenhouse gas benefits. This issue has been especially critical in the past several years, when indirect effects, such as indirect land use changes, associated with U.S. corn ethanol production are considered in evaluation. In the past three years, modeling of direct and indirect land use changes related to the production of corn ethanol has advanced significantly. Meanwhile, technology improvements in key stages of the ethanol life cycle (such as corn farming and ethanol production) have been made. With updated simulation results of direct and indirect land use changes and observed technology improvements in the past several years, we conducted a life-cycle analysis of ethanol and show that at present and in the near future, using corn ethanol reduces greenhouse gas emission by more than 20%, relative to those of petroleum gasoline. On the other hand, second-generation ethanol could achieve much higher reductions in greenhouse gas emissions. In a broader sense, sound evaluation of U.S. biofuel policies should account for both unanticipated consequences and technology potentials. We maintain that the usefulness of such evaluations is to provide insight into how to prevent unanticipated consequences and how to promote efficient technologies with policy intervention.  相似文献   

9.
The increase in greenhouse gas concentrations in the atmosphere, energy security issues and competition for land use are putting pressure on governments and policymakers. However, these three subjects are not usually treated in integrated form. This paper shows that the implementation of energy efficiency policies combined with policies to encourage use of biofuels can help reduce greenhouse gases emissions while easing land use competition from sugarcane ethanol in Brazil. By adapting the ADVISOR (Advanced Vehicle Simulator) software to evaluate vehicle efficiency, and by estimating the Brazilian light-duty vehicle market share based on historical data, this paper estimates the possible levels of GHG emissions and area planted with sugarcane in 2030 in the country. The findings indicate that reductions from 8% to 20% in greenhouse gas emissions and 0.9–1.8 million ha in sugarcane planted area are possible with no significant technological breakthroughs over the horizon to 2030 in comparison with a baseline scenario.  相似文献   

10.
This paper describes and analyses the multi-actor governance process that made Mozambique the first African nation-state to develop a national policy framework for sustainable biofuels. The paper draws on findings from action research conducted in Mozambique between December 2008 and July 2012. We analyse interactions between the changing governance context, the course of the multi-actor governance process, and the choices in relation to governance framework characteristics and content for four successive stages of governance framework development. This provides the basis for reflection on the competences required for effective multi-actor sustainability governance, and a discussion about the role of the nation-state in sustainability governance of global economies such as biofuels.The governance framework for sustainable biofuels has contributed to a more transparent and secure investment climate for biofuels in Mozambique. Key factors for success were (1) the presence of different types of competences during the various stages of the governance framework development, (2) closing the gap between ‘licences to sell’ and ‘licences to produce’ across different governance levels, and (3) balancing between the short- and long-term objectives for biofuel production in Mozambique and requirements of global biofuel markets. Developing-country nation-states can provide an essential contribution to these success-factors for global governance of sustainable biofuels.  相似文献   

11.
The purpose of the present study is to evaluate bioenergy supply potentials, land use changes, and CO2 emissions in the world, using a global land use and energy model (GLUE) including land use competitions and overall biomass flows. Through a set of simulations, the following results were obtained: (1) Supply potentials of energy crops produced from surplus arable lands will be strongly affected by food supply and demand parameters in the future, such as animal food demand per capita. (2) The policy option, i.e. the world, large-scale introduction of modern fuelwood by felling and planting in existing forest, will cause drastic reduction of the mature forest area but will cause little reduction of the accumulated CO2 emissions coming from both energy and forest sectors. One reason for this is that the additional CO2 emissions owing to the land use conversion from the mature forest to the growing forest will partly cancel out the CO2 reduction owing to the fuel substitution from fossil fuels to fuelwood. (3) When energy recovery of paper scrap is given priority to material recycling, bioenergy will substitute partly for fossil fuels; however the decrease in recycled paper scrap will cause an increase in roundwood felling demand. Hence, the results will be similar to those of (2).  相似文献   

12.
This paper describes a methodology to explore the (future) spatial distribution of biofuel crops in Europe. Two main types of biofuel crops are distinguished: biofuel crops used for the production of biodiesel or bioethanol, and second-generation biofuel crops. A multi-scale, multi-model approach is used in which biofuel crops are allocated over the period 2000-2030. The area of biofuel crops at the national level is determined by a macro-economic model. A spatially explicit land use model is used to allocate the biofuel crops within the countries. Four scenarios have been prepared based on storylines influencing the extent and spatial distribution of biofuel crop cultivation. The allocation algorithm consists of two steps. In the first step, processing plants are allocated based on location factors that are dependent on the type of biofuel crop processed and scenario conditions. In the second step, biofuel crops are allocated accounting for the transportation costs to the processing plants. Both types of biofuel crops are allocated separately based on different location factors. Despite differences between the scenarios, mostly the same areas are showing growth in biofuel crop cultivation in all scenarios. These areas stand out because they have a combination of well-developed infrastructural and industrial facilities and large areas of suitable arable land. The spatially explicit results allow an assessment of the potential consequences of large-scale biofuel crop cultivation for ecology and environment.  相似文献   

13.
"Indirect land use change for biofuels: Testing predictions and improving analytical methodologies" by S. Kim and B. Dale [1], presents a principal inference not supported by its results, that rests on a fundamental conceptual error, and that has no place in the current discussion of biofuels’ climate effects. The paper takes correlation between two variables in a system with many interacting factors to indicate (or contraindicate) causation, and draws a completely incorrect inference from observed sample statistics and their significance levels.  相似文献   

14.
李丽  张维奇 《江西能源》2006,(2):9-11,26
本文以1992年、2002年两期的遥感数据和其它CIS数据、专题图等为基础,利用面向对象的方法进行解译,对万州区10年的土地利用/土地覆被变化进行了分析,结果表明:10年间建设用地、草地有较大的增长,其它类型都呈现不同程度的衰减;建设用地增加1372.7hm^2,占总变化面积的26.26%。主要来自耕地的减少,草地的动态度也较高,达到5.58;通过对景观格局的分析,该区的景观的异质程度提高,土地趋于多样化,优势度降低,10年景观类型发生了较大的变化。  相似文献   

15.
Facing climate change and growing energy prices, the use of bioenergy is continuously increasing in order to diminish greenhouse gas emissions, secure energy supply and create employment in rural areas. Because the production of biomass or biofuels, wherever it takes place, comes along with externalities, positive or negative, the need for biomass and bioenergy sustainability criteria is more than ever felt. Research on sustainability criteria and certification systems has started through several national and international initiatives. Considering the benefits of an increased use of bioenergy but also the urge for limiting potential negative environmental and socio-economic impacts, the aim of these initiatives was to make the first move regarding bioenergy sustainability, while waiting for the European legislation to regulate this crucial issue. Land use changes, whether direct or indirect, are one of the most important consequences of bioenergy production. While direct land use changes are more easily assessed locally, indirect land use changes exceed the company level and need to be considered at a global scale. Methodologies for dealing with direct and indirect land use changes are proposed among others in the European, Dutch, British and German sustainability initiatives. This paper aims at presenting and comparing those four European initiatives, with a focus on their propositions for direct and indirect land use changes assessment. Key issues are discussed and recommendations are made for steps to overcome identified difficulties in accurately assessing the effects of indirect land use change due to bioenergy production.  相似文献   

16.
Anaerobic digestion (AD) is of growing importance within the UK as it can make an important contribution to the countries energy and climate change targets. With the growth of the sector, discussions about competing land uses are likely to increase. For a better understanding of the synergies between agricultural land, its role and bioenergy the perception of the different stakeholders will play an important role. The perception of stakeholders related to AD, feedstock and energy crop production was investigated through interviews and a stakeholder workshop. The results indicated that from an AD operator and feedstock producer perspective, on-farm AD is more an additional activity integrated into existing agricultural systems than a renewable energy technology. The risk of a shift in agricultural practices and large areas to grow energy crops for AD is seen as low for the UK. Nonetheless, land use and related challenges need to be considered as the demand for AD feedstocks increases with the fast growth of the sector. Considering the synergies between bioenergy and agriculture as well as the motivations and benefits perceived by stakeholders will play an important role in a successful policy design to provide the required emission reduction in both sectors without subverting sustainability.  相似文献   

17.
Biomass from cellulosic bioenergy crops is seen as a substantial part of future energy systems, especially if climate policy aims at stabilizing CO2 concentration at low levels. However, among other concerns of sustainability, the large-scale use of bioenergy is controversial because it is hypothesized to increase the competition for land and therefore raise N2O emissions from agricultural soils due to intensification. We apply a global land-use model that is suited to assess agricultural non-CO2 GHG emissions. First, we describe how fertilization of cellulosic bioenergy crops and associated N2O emissions are implemented in the land-use model and how future bioenergy demand is derived by an energy-economy-climate model. We then assess regional N2O emissions from the soil due to large-scale bioenergy application, the expansion of cropland and the importance of technological change for dedicated bioenergy crops. Finally, we compare simulated N2O emissions from the agricultural sector with CO2 emissions from the energy sector to investigate the real contribution of bioenergy for low stabilization scenarios.As a result, we find that N2O emissions due to energy crop production are a minor factor. Nevertheless, these co-emissions can be significant for the option of removing CO2 from the atmosphere (by combining bioenergy use with carbon capture and storage (CCS) options) possibly needed at the end of the century for climate mitigation. Furthermore, our assessment shows that bioenergy crops will occupy large shares of available cropland and will require high rates of technological change at additional costs.  相似文献   

18.
This work models the carbon neutralization capacity of Brazil's ethanol program since 1975. In addition to biofuel, we also assessed the mitigation potential of other energy products, such as, bioelectricity, and CO2 emissions captured during fermentation of sugar cane's juice. Finally, we projected the neutralization capacity of sugar cane's bio-energy system over the next 32 years. The balance between several carbon stocks and flows was considered in the model, including the effects of land-use change. Our results show that the neutralization of the carbon released due to land-use change was attained only in 1992, and the maximum mitigation potential of the sugar cane sector was 128 tonnes of CO2 per ha in 2006. An ideal reconstitution of the deployment of the sugar cane sector, including the full exploitation of bio-electricity's potential, plus the capture of CO2 released during fermentation, shows that the neutralization of land-use change emissions would have been achieved in 1988, and its mitigation potential would have been 390 tCO2/ha. Finally, forecasts of the sector up to 2039 shows that the mitigation potential in 2039 corresponds to 836 tCO2/ha, which corresponds to 5.51 kg of CO2 per liter of ethanol produced, or 55% above the negative emission level.  相似文献   

19.
This paper describes five energy conservation land use planning strategies for municipal planning, and indicates their usage in Canadian municipalities. The paper is instructive to urban planners, engineers, administrators and others who seek practical information on the energy conservation opportunities of manipulating land use and structural characteristics.  相似文献   

20.
The combination of bioenergy production and carbon capture and storage technologies (BECCS) provides an opportunity to create negative emissions of CO2 in biofuel production. However, high capture costs reduce profitability. This paper investigates carbon price uncertainty and technological uncertainty through a real option approach. We compare the cases of early and delayed CCS deployments. An early technological progress may arise from aggressive R&D and pilot project programs, but the expected cost reduction remains uncertain. We show that this approach results in lower emissions and more rapid investment returns although these returns will not fully materialise until after 2030. In a second set of simulations, we apply an incentive that prioritises sequestered emissions rather than avoided emissions. In other words, this economic instrument does not account for CO2 emissions from the CCS implementation itself, but rewards all the sequestered emissions. In contrast with technological innovations, this subsidy is certain for the investor. The resulting investment level is higher, and the project may become profitable before 2030. Negative emission in bioethanol production does not seem to be a short-term solution in our framework, whatever the carbon price drift.  相似文献   

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