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1.
This Address considers a range of issues relating to the contribution of meat consumption and livestock production to global warming, given the need highlighted by the Committee on Climate Change (CCC) to reduce global GHG emissions by over 50% by 2050. The IPCC Climate Change 2014 report recognised that demand oriented measures may also contribute to GHG mitigation. The paper reviews a number of studies which examine demand‐led mitigation potentials, and concludes that such estimates ignore the market effects of changes in meat consumption habits or demand oriented policies. A simple partial equilibrium model of beef, poultry, pig and ovine meats is developed for the major regions of the world to explore the impact of a range of scenarios which might reduce meat consumption and GHG emissions. These include emissions taxation, long‐term trends in reduction of red meat consumption in developed economy regions, and supply side improvements in livestock emissions intensities. The paper discusses problems associated with many published demand elasticities suitable for incorporation into a market model, problems of selection from widely varying published estimates and their appropriateness for longer‐run projections. The dearth of published supply elasticity estimates is also highlighted. The modelling concludes that economic and population growth to 2050 without any mitigation measures will lead to a 21% increase in per capita meat consumption and a 63% increase in total consumption and GHG emissions by 2050. However, the mitigation projections from the scenarios explored only generate a 14% reduction in cumulative emissions from the baseline 2050 projections, insufficient to meet the CCC target.  相似文献   

2.
With increasing awareness of agriculture's contribution to global greenhouse gases (GHGs) and China's position as the world's top GHG emitter, there is heightened attention to the embodied emissions in China's food consumption. China's diet has shifted to include more fruit, vegetables, meat and dairy. Not surprisingly, GHG emissions from food consumption have also increased substantially. This analysis links China's food consumption with the emissions of food production industries in China and its trade partners to determine the effects of dietary change on GHGs since 1989. We utilise high‐resolution food production and emissions data to perform a logarithmic mean Divisia index decomposition to attribute changes in GHG emissions to the scale, supply structure, demand structure and efficiency effects resulting from Chinese dietary changes over a 20‐year period. This study finds that while countries supplying food to China contribute little to China's food‐related GHGs, demands for meat and dairy play a much larger role, driving up emissions. The overall scale of increased consumption of all food further propels growth in GHG emissions. Results indicate, however, that while food consumption in China more than doubles between 1989 and 2009 improvements in technological efficiency limit the rate of increase.  相似文献   

3.
[目的]由于自然要素组合的特殊性,与传统内陆农区相比,滩涂围垦区农业生产特点鲜明。摸清该区大田作物碳足迹,可减少区域碳排放,提升农业生产效率,优化区域资源配置。[方法]采用生命周期评价理论结合IPCC田间温室气体计算方法,建立大田作物碳足迹评估模型,估算滨海滩涂垦区大田作物温室气体排量。[结果](1)滨海滩涂地区大田作物的碳足迹(以CO_2当量)总体在0.63~0.769kg/kg范围内,不同作物的碳足迹由大到小依次为:玉米0.769±0.224kg/kg、水稻0.739±0.241kg/kg、小麦0.636±0.183kg/kg和大麦0.630±0.184kg/kg;(2)氮肥生产和施用环节对该区碳足迹贡献度最大,贡献率分别为26.46%~37.12%和29.06%~51.94%。该地碳足迹数值和结构上呈显著地域化特点,与中国其他地区相比,氮肥施用贡献度大,水田灌溉贡献度大。[结论]降低该地区碳足迹,重点关注施氮和水稻灌溉工程两个方面。采用降低施氮量、提高氮肥利用率、发展节水农业与生态农业等措施,可达到降低碳足迹的目的。  相似文献   

4.
The growing concerns of climate change require implementing measures to quantify, to monitor and to minimize greenhouse gas (GHG) emissions. Nonetheless, most of the measures available are not easy to define or execute because they rely on current emissions and have a corrective character. To address this issue, a methodology to characterize GHG emissions that allows implementing preventive measures is proposed in this paper. The methodology is related to household urban planning procedures and considers urban infrastructures to characterize GHG emissions and to execute preventive measures based on sustainability design criteria. The methodology has been tested by applying it to a set of medium-sized municipalities with average GHG emissions from 6,822.32 kgCO2eq/year to 5,913.79 kgCO2eq/year for every residential unit. The results indicate that the greatest pollutant source is transport, especially in the issuance of street network design, followed by gas and electricity consumption. The average undevelopable land area required for the complete GHG emissions capture amounts to 3.42 m2 of undevelopable land for every m2 of urbanizable land and 9.02 m2 of undevelopable land for every m2 of built land.  相似文献   

5.
Three steps are required to successfully and efficiently reduce greenhouse gas (GHG) emissions from agriculture: (i) identification of the most GHG polluting farms, (ii) determining appropriate mitigation options for these farms, and (iii) selection between these options on the basis of their cost effectiveness. Carbon footprints of a sample of farms together with an analysis of the Kyoto Protocol show the difficulties encountered at each step. These difficulties are caused by: (i) failure to agree which functional unit to use to measure GHG emissions and pollution swapping; (ii) weaknesses in the Kyoto Protocol's territorial/production based accounting methodology, and (iii) lack of cost-effectiveness data. One consequence is that farmers may adopt mitigation activities that reduce their farm's, the UK agriculture sector's and the UK's emissions whilst inadvertently increasing global emissions: a trivial solution because it fails to address GHG emissions as a global problem. These difficulties, together with estimated agriculture sector marginal abatement cost curves that suggests emission reduction from all cost effective mitigation activities will not deliver targeted GHG emission reductions, means policy focus must be on demand rather than supply-side measures: the benefits and disadvantages of cap and trade mechanisms and carbon taxes are briefly discussed within an agricultural context.  相似文献   

6.
The global land use implications of biofuel expansion have received considerable attention in the literature over the past decade. Model‐based estimates of the emissions from cropland expansion have been used to assess the environmental impacts of biofuel policies. And integrated assessment models have estimated the potential for biofuels to contribute to greenhouse gas (GHG) abatement over the coming century. All of these studies feature, explicitly or implicitly, competition between biofuel feed stocks and other land uses. However, the economic mechanisms governing this competition, as well as the contribution of biofuels to global land use change, have not received the close scrutiny that they deserve. The purpose of this article is to offer a deeper look at these factors. We begin with a comparative static analysis which assesses the impact of exogenously specified forecasts of biofuel expansion over the period: 2006–2035. Global land use change is decomposed according to the three key margins of economic response: extensive supply, intensive supply, and demand. Under the International Energy Agency's “New Policies” scenario, biofuels account for nearly one‐fifth of global land use change over the 2006–2035 period. The article also offers a comparative dynamic analysis which determines the optimal path for first and second generation biofuels over the course of the entire 21st century. In the absence of GHG regulation, the welfare‐maximizing path for global land use, in the face of 3% annual growth in oil prices, allocates 225 Mha to biofuel feed stocks by 2100, with the associated biofuels accounting for about 30% of global liquid fuel consumption. This area expansion is somewhat diminished by expected climate change impacts on agriculture, while it is significantly increased by an aggressive GHG emissions target and by advances in conversion efficiency of second generation biofuels.  相似文献   

7.
The agricultural sector is currently confronted with the challenge to reduce greenhouse gas (GHG) emissions, whilst maintaining or increasing production. Energy-saving technologies are often proposed as a partial solution, but the evidence on their ability to reduce GHG emissions remains mixed. Production economics provides methodological tools to analyse the nexus of agricultural production, energy use and GHG emissions. Convexity is predominantly maintained in agricultural production economics, despite various theoretical and empirical reasons to question it. Employing non-convex and convex frontier frameworks, this contribution evaluates energy productivity change (the ratio of aggregate output change to energy use change) and GHG emission intensity change (the ratio of GHG emission change to polluting input change) using Hicks-Moorsteen productivity formulations. We consider GHG emissions as by-products of the production process by using a multi-equation model. Given our empirical specification, non-convex and convex Hicks-Moorsteen indices can coincide under certain circumstances, which leads to a series of theoretical equivalence results. The empirical application focuses on 1,510 observations of Dutch dairy farms for the period of 2010–2019. The results show a positive association between energy productivity change and GHG emission intensity change, which calls into question the potential of on-farm, energy-efficiency-increasing measures to reduce GHG emission intensity.  相似文献   

8.
The motivation for this study stems from two major concerns that are interlinked. The first is the decades long food insecurity crisis faced by sub‐Saharan African (SSA) countries which is still prevalent. The second is the negative impact greenhouse gas (GHG) emissions from agriculture may have on future food production and which is likely to worsen the food insecurity problem. The conundrum SSA farmers face is how to increase food output through productivity growth while minimizing GHG emissions. To measure changes in productivity growth and GHG emissions, this study evaluates the agricultural performance of 18 SSA countries by utilizing the Malmquist–Luenberger index to incorporate good and bad outputs for the years 1980–2012. The empirical evidence demonstrates that productivity is overestimated when bad outputs are not considered in the production model. The analysis provides a better understanding of the effectiveness of previous mitigation methods and which informs an appropriate course of action needed to achieve the twin objectives of increasing agriculture productivity while reducing GHG emissions.  相似文献   

9.
In recent decades there have been significant changes in land use and production orientation in certain marginal agricultural areas in the southwest of Spain. The abandonment of rainfed cereal crops and their change of use as natural pastures grazed by milk sheep, have led to an improvement in the profitability of the farms, greater industrialisation and a positive impact on rural development.This paper calculates the carbon footprint (CF) of farms in the context of life cycle assessment with the objective to identify the system that accounts for the lowest CF while maintaining adequate levels of profitability and revitalising the rural environment. The data were obtained through surveys carried out on dairy sheep farms of different typologies, ranging from the semi-intensive farms with small grazing areas, to the extensive farms with large areas of natural pastures. Findings could help farmers evaluate the environmental impact of their activities, while at the same time provide consumers with valuable evidence to be used in further marketing actions.Greenhouse gas emissions vary from 1.77 to 4.09 Kg CO2eq/kg of milk, where the lowest values correspond to the most intensive farms and the highest values to the most extensive and least productive farms. Enteric fermentation, followed by feeding, are the emissions with the greatest impact. Enteric fermentation reaches its maximum value (52.22 % of the total emissions) in the most extensive farms.On other hand, this study found that carbon sequestration varies between 0.09 and 2.04 kg of CO2eq/kg of milk, a figure that can considerably reduce the carbon footprint calculation and justifies its inclusion in the Life Cycle Assessment.  相似文献   

10.
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   

11.
In this paper we analyse the economic and environmental impacts of CAP greening introduced by the 2013 CAP reform using the CAPRI model. CAPRI captures the farm heterogeneity across the EU and it allows to depict the implementation of the greening measures in high detail while integrating the environmental effects and the market feedback of the simulated policy changes. The simulated results reveal that the economic impacts (land use, production, price and income) of CAP greening are rather small, although some farm types, crops (fallow land and pulses) and Member States may be affected more significantly. The CAP greening will lead simultaneously to a small increase in prices and a small decrease in production. Farm income slightly increases because the price effects offset the production decline. Similarly to economic effects, the environmental impacts (GHG emissions, N surplus, ammonia emissions, soil erosion, and biodiversity‐friendly farming practices) of CAP greening are small, although some regions may see greater effects than others. In general, the environmental effects at EU level are positive on a per hectare basis, but the increase in UAA can reverse the sign for total impacts. Overall, simulated GHG and ammonia emissions decrease in the EU, while the total N surplus, soil erosion and biodiversity‐friendly farming practices indicator slightly increase due to the CAP greening.  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.
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   

14.
One consequence of increasing agricultural trade is a shift of geographic location of agricultural activity to more economically productive countries. Whether or not the economic efficiency translates to environmental efficiency for agricultural goods is an open question. To examine environmental implications of shifting agricultural location, we analysed the life-cycle greenhouse gas (GHG) emissions of rice production in Japan and the US for the Japanese market in a comparative manner. This paper presents the life-cycle assessment of brown japonica rice. Our computation of GHG emissions of rice production in Japan and the US were 3.54 and 2.99?kgCO2-eq kg-rice?1, respectively. With respect to harvested area, the emissions were 18.4 in Japan and 27.8?tCO2-eq ha?1 in the US. For Japan to be environmentally competitive with the US production, fundamental restructuration of field size is necessary to increase yield. In conclusion, economic efficiency does not translate to environmental efficiency with the case of rice production. Importing rice is both economically and environmentally viable option for the Japanese market.  相似文献   

15.
Policies regulating greenhouse gas (GHG) emissions are expected to create a significant burden on emitting industries as well as final consumers, which can lead to a strong influence on international trade flows of commodities. This study examines whether the regulation of GHG emissions affects livestock trade flows. A commodity‐specific gravity model approach is employed to estimate and test the impact of regulating GHG emissions on livestock trade flows. The results show that regulation of GHG emissions has a negative effect on livestock trade flows from countries restricting GHG emissions to countries without GHG restriction, from restricting countries to restricting countries, and unrestricting countries to restricting countries.  相似文献   

16.
European farmland hosts a species assemblage of animals and plants which have undergone declines through the late twentieth and early twenty-first centuries, at least partly as a result of increased productivity. Further increases in human populations, changes in availability and cost of raw materials, policy constraints, price volatility and climatic changes will further drive greater efficiency and high yields in agriculture, with the risk of further adverse environmental impacts. We assess the effects of different management priorities (production-driven cropping vs. wildlife-friendly farming) at an arable farm in eastern England on food production, greenhouse gas (GHG) emissions and biodiversity. We modelled one actual and three alternative cropping scenarios using actual yields from the farm over 13 years, to calculate total yields and those foregone for agri-environmental measures. We measured crop yields, relative abundance of 19 farmland bird species, and CO2 and N2O emissions related to crop production. Removing up to 10.5% of land from production coupled with a more diverse rotation (including legumes) resulted in a large increase in breeding birds (177%) and reduction of 9.4% in GHG emissions at the cost of 9.6% of food energy. Food protein lost was only 2.9%. A smaller increase in bird numbers of 50% could be achieved at a much smaller cost to yield (~1.7% energy or protein) but with correspondingly smaller emissions reductions (1.2%). Results are discussed within the context of continued biodiversity loss to agriculture, increasing food demand and changing diets.  相似文献   

17.
Due to land use effects, bioenergy use may cause adverse effects on biodiversity, soil and water and may even fail to guarantee a GHG emissions reduction compared to fossil fuel use. Accounting methodologies and policy instruments were elaborated to prevent these effects, but there is still no sound and consensual methodology to take into account indirect land use change that substantially contributes to GHG emissions as well as a loss of biodiversity. While the iLUC hypothesis, that is the potentiality of adverse effects arising from indirect land use change related to biomass cultivation, is hardly subject to dispute, the quantification of these effects and especially their policy implications are however contentious. Hence, bioenergy policies worldwide face a dilemma: Neglecting iLUC effects that do in fact exist or taking them into account although no sound methodology is available? The article covers the current state of the discussion and also analyses the approaches developed for taking indirect land use change into account. Assessment criteria for coping with the iLUC dilemma are developed and policy recommendations are derived from that.  相似文献   

18.
Brazil is trying to identify ways to ally economic growth with climate change mitigation. Productivity gains in livestock have been pointed out as a promising alternative to achieve that goal. Thus, this paper analyses the economic impacts of a policy of productivity gains in the Brazilian livestock. Besides, we evaluate if the policy may conciliate agricultural growth and deforestation control, bearing in mind the reduction of greenhouse gas (GHG) emissions from land-use changes. The analysis was carried out through a computable general equilibrium (CGE) model, tailored to represent land-use changes, GHG emissions and removals. Besides, it made progress modeling the heterogeneity of climate, soils, and emissions in inter-regional models with many regions. The results show that productivity gains can effectively “save” land and thus avoid deforestation, especially in the Amazon and Cerrado (savannah) biomes. The policy also may boost the economic growth, spreading it to other regions of Brazil, like Centre-West and North, and increasing income and consumption in those places. However, as a climate policy, focused on the reduction of GHG emissions, the results may be counterproductive. The net amount issued may increase, as a result of the positive stimulus of the policy on the economy, and GHG emissions are directly related to the economic growth.  相似文献   

19.
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   

20.
This paper examines the relationships between the marginal abatement costs (MAC) of greenhouse gas (GHG) emissions on dairy farms and factors such as herd size, milk yield and available farm labour, on the one hand, and prices, GHG indicators and GHG reduction levels, on the other. A two‐stage Heckman procedure is used to estimate these relationships from a systematically designed set of simulations with a highly detailed mixed integer bio‐economic farm‐level model. The resulting meta‐models are then used to analyse how MAC vary across farm‐level conditions and GHG measures. We find that simpler GHG indicators lead to significantly higher MAC, and that MAC strongly increase beyond a 1–5% emission reduction, depending on farm attributes and the chosen indicator. MAC decrease rapidly with increasing farm size, but the effect levels off beyond a herd size of 40 cows. As expected, the main factors driving gross margins per dairy cow also significantly influence mitigation costs. Our results indicate high variability of MAC on real life farms. In contrast to time consuming simulations with the complex mixed integer bio‐economic programming model, the meta‐models allow the distribution of MAC in a farm population to be efficiently derived and thus could be used to upscale to regional or sector level.  相似文献   

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