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1.
Exploring the environmental impact of dietary consumption has become increasingly important to understand the carbon-water-food nexus, vital to achieving UN sustainable development goals. However, the research on diet-based nexus assessment is still lacking. Here, we developed an Environmentally Extended Multi-Regional Input-Output (EE-MRIO) model with compiling a global MRIO table based on the latest Global Trade Analysis Project (GTAP) 10 database, where we specifically constructed a water withdrawal account and matched it to each economy at the sectoral level. The regional heterogeneity and synergy of carbon-water nexus affected by dietary patterns in nine countries was explored. The results show that: (1) Dietary consumption is the main use of water withdrawal for each country; Japan, the US, South Korea, and India have a high per capita dietary water footprint. Mainly due to consumption of processed rice, Japan has the highest per capita value of 488 M3/year, accounting for 63.4% of the total water footprint. (2) The total dietary carbon footprints in China, India, and the US are high, which is mainly caused by the high consumption of animal products (including dairy) either due to the large population (China, India) or animal-based diet (the US). Americans have the highest per capita dietary carbon footprint, reaching 755.4 kg/year, 2.76 times that of the global average. (3) Generally, imported/foreign footprints account for a greater share in dietary water and carbon footprints of developed countries with an animal-based diet. (4) In the nexus analysis, the US, Japan, and South Korea are key-nexus countries, vegetables, fruit and nuts, tobacco and beverages, and other food products are selected as key-nexus sectors with relatively high dietary water and carbon footprint. Furthermore, dietary consumption choices lead to different environmental impacts. It is particularly important to find a sustainable dietary route adapted to each country considering that heterogeneity and synergism exist in key-nexus sectors to achieve the relevant Sustainable Development Goals.  相似文献   

2.
The production of animal-based foods is associated with higher greenhouse gas (GHG) emissions than plant-based foods. The objective of this study was to estimate the difference in dietary GHG emissions between self-selected meat-eaters, fish-eaters, vegetarians and vegans in the UK. Subjects were participants in the EPIC-Oxford cohort study. The diets of 2,041 vegans, 15,751 vegetarians, 8,123 fish-eaters and 29,589 meat-eaters aged 20–79 were assessed using a validated food frequency questionnaire. Comparable GHG emissions parameters were developed for the underlying food codes using a dataset of GHG emissions for 94 food commodities in the UK, with a weighting for the global warming potential of each component gas. The average GHG emissions associated with a standard 2,000 kcal diet were estimated for all subjects. ANOVA was used to estimate average dietary GHG emissions by diet group adjusted for sex and age. The age-and-sex-adjusted mean (95 % confidence interval) GHG emissions in kilograms of carbon dioxide equivalents per day (kgCO2e/day) were 7.19 (7.16, 7.22) for high meat-eaters (?>?=?100 g/d), 5.63 (5.61, 5.65) for medium meat-eaters (50-99 g/d), 4.67 (4.65, 4.70) for low meat-eaters (?<?50 g/d), 3.91 (3.88, 3.94) for fish-eaters, 3.81 (3.79, 3.83) for vegetarians and 2.89 (2.83, 2.94) for vegans. In conclusion, dietary GHG emissions in self-selected meat-eaters are approximately twice as high as those in vegans. It is likely that reductions in meat consumption would lead to reductions in dietary GHG emissions.  相似文献   

3.
Meeting the food needs of the growing and increasingly affluent human population with the planet’s limited resources is a major challenge of our time. Seen as the preferred approach to global food security issues, ‘sustainable intensification’ is the enhancement of crop yields while minimizing environmental impacts and preserving the ability of future generations to use the land. It is still unclear to what extent sustainable intensification would allow humanity to meet its demand for food commodities. Here we use the footprints for water, nitrogen, carbon and land to quantitatively evaluate resource demands and greenhouse gas (GHG) emissions of future agriculture and investigate whether an increase in these environmental burdens of food production can be avoided under a variety of dietary scenarios. We calculate average footprints of the current diet and find that animal products account for 43–87% of an individual’s environmental burden – compared to 18% of caloric intake and 39% of protein intake. Interestingly, we find that projected improvements in production efficiency would be insufficient to meet future food demand without also increasing the total environmental burden of food production. Transitioning to less impactful diets would in many cases allow production efficiency to keep pace with growth in human demand while minimizing the food system’s environmental burden. This study provides a useful approach for evaluating the attainability of sustainable targets and for better integrating food security and environmental impacts.  相似文献   

4.
The potential greenhouse gas (GHG) emissions from the production of food for three different diets are compared using consequential Life Cycle Assessment. Diet 1 is an Average Danish Diet (ADD); diet 2 is based on the Nordic Nutritional Recommendations (NNR), whilst diet 3 is a New Nordic Diet (NND) developed by the OPUS project. The NND contains locally produced Nordic foods where more than 75 % is organically produced. NNR and NND include less meat and more fruit and vegetables than the ADD. All diets were adjusted to contain a similar energy and protein content. The GHG emissions from the provision of NNR and NND were lower than for ADD, 8 % and 7 % respectively. If GHG emissions from transport (locally produced versus imported food) are also taken into account, the difference in GHG emissions between NND and ADD increases to 12 %. If the production method (organic versus conventional) is taken into account so that the ADD contains the actual ratio of organically produced food (6.6 %) and the NND contains 80 %, the GHG emissions for the NND are only 6 % less than for the ADD. When the NND was optimised to be more climate friendly, the global warming potential of the NND was 27 % lower than it was for the ADD. This was achieved by including less beef, and only including organic produce if the GHG emissions are lower than for the conventional version, or by substituting all meat with legumes, dairy products and eggs.  相似文献   

5.
Low-meat and no-meat diets are increasingly acknowledged as sustainable alternatives to current Western food consumption patterns. Concerns for the environment, individual health or animal welfare are raising consumers’ willingness to adopt such diets. Dietary shifts in Western countries may modify the way human-environment systems interact over distances, primarily as a result of existing trade flows in food products. Global studies have focused on the amount of water, land, and CO2 emissions embodied in plant-based versus animal-based proteins, but the potential of alternative diets to shift the location of environmental impacts has not yet been investigated. We build on footprint and trade-based analyses to compare the magnitude and spatial allocation of the impacts of six diets of consumers in the United States of America (USA). We used data on declared diets as well as a stylized average diet and a recent dietary guideline integrating health and environmental targets. We demonstrate that low-meat and no-meat diets have a lower demand for land and utilize more crops with natural nitrogen fixation potential, yet also rely more widely on pollinator abundance and diversity, and can increase impacts on freshwater ecosystems in some countries. We recommend that governments carefully consider the local impacts of the alternative diets they promote, and minimize trade-offs between the global and local consequences of dietary shifts through regulation or incentives.  相似文献   

6.
More sustainable dietary patterns are needed to mitigate global warming. This study aims to identify data-driven healthy dietary patterns that benefit the environment. In EPIC-NL, diet was assessed using a 178-item FFQ in 36,203 participants aged 20–70 years between 1993 and 1997. The Dutch Healthy Diet index 2015 (DHD15-index) was used to score healthiness of the diet. As proxy for environmental impact, greenhouse gas (GHG) emissions were calculated using life cycle analysis. To determine patterns that are both healthy and environmentally friendly, reduced rank regression was applied. A “Plant-based Pattern” characterized by high consumption of fruits, vegetables, and legumes, and low consumption of fries, red meat, and processed meat and a “Dairy-based Pattern” characterized by high consumption of dairy, and nuts and seeds and low consumption of coffee and tea, sugar-containing sodas, low-fiber bread, and savory sauces were derived. At equal energy intake, the diet of adherents (highest quartile) to the “Plant-based Pattern” were significantly healthier (89.8 points on the DHD15-index, p?<?0.0001) and more sustainable (3.96 kg C02-eq/day, p?<?0.0001) compared to the average diet (76.2 points, 4.06 kg C02-eq/day), whereas the “Dairy-based Pattern” was somewhat healthier (77.9 points, p?<?0.0001), but less sustainable (4.43 kg C02-eq/day, p?<?0.0001). When deriving dietary patterns based on health and environmental aspects of the diets, a “Plant-based” and a “Dairy-based” pattern were observed in our study population. Of these, the plant-based diet benefits health as well as the environment.  相似文献   

7.
Today, the agricultural sector accounts for approximately 15% of total global anthropogenic emissions, mainly methane and nitrous oxide. Projecting the future development of agricultural non-CO2 greenhouse gas (GHG) emissions is important to assess their impacts on the climate system but poses many problems as future demand of agricultural products is highly uncertain. We developed a global land use model (MAgPIE) that is suited to assess future anthropogenic agricultural non-CO2 GHG emissions from various agricultural activities by combining socio-economic information on population, income, food demand, and production costs with spatially explicit environmental data on potential crop yields. In this article we describe how agricultural non-CO2 GHG emissions are implemented within MAgPIE and compare our simulation results with other studies. Furthermore, we apply the model up to 2055 to assess the impact of future changes in food consumption and diet shifts, but also of technological mitigation options on agricultural non-CO2 GHG emissions. As a result, we found that global agricultural non-CO2 emissions increase significantly until 2055 if food energy consumption and diet preferences remain constant at the level of 1995. Non-CO2 GHG emissions will rise even more if increasing food energy consumption and changing dietary preferences towards higher value foods, like meat and milk, with increasing income are taken into account. In contrast, under a scenario of reduced meat consumption, non-CO2 GHG emissions would decrease even compared to 1995. Technological mitigation options in the agricultural sector have also the capability of decreasing non-CO2 GHG emissions significantly. However, these technological mitigation options are not as effective as changes in food consumption. Highest reduction potentials will be achieved by a combination of both approaches.  相似文献   

8.
The main assumptions and findings are presented on a comparative analysis of three GHG long-term emissions scenarios for Brazil. Since 1990, land-use change has been the most important source of GHG emissions in the country. The voluntary goals to limit Brazilian GHG emissions pledged a reduction in between 36.1% and 38.9% of GHG emissions projected to 2020, to be 6–10% lower than in 2005. Brazil is in a good position to meet the voluntary mitigation goals pledged to the United Nations Framework Convention on Climate Change (UNFCCC) up to 2020: recent efforts to reduce deforestation have been successful and avoided deforestation will form the bulk of the emissions reduction commitment. In 2020, if governmental mitigation goals are met, then GHG emissions from the energy system would become the largest in the country. After 2020, if no additional mitigation actions are implemented, GHG emissions will increase again in the period 2020–2030, due to population and economic growth driving energy demand, supply and GHG emissions. However, Brazil is in a strong position to take a lead in low-carbon economic and social development due to its huge endowment of renewable energy resources allowing for additional mitigation actions to be adopted after 2020.

Policy relevance

The period beyond 2020 is now relevant in climate policy due to the Durban Platform agreeing a ‘protocol, legal instrument or agreed outcome with legal force’ that will have effect from 2020. After 2020, Brazil will be in a situation more similar to other industrialized countries, faced with a new challenge of economic development with low GHG energy-related emissions, requiring the adoption of mitigation policies and measures targeted at the energy system. Unlike the mitigation actions in the land-use change sector, where most of the funding will come from the national budgets due to sovereignty concerns, the huge financial resources needed to develop low-carbon transport and energy infrastructure could benefit from soft loans channelled to the country through nationally appropriate mitigation actions (NAMAs).  相似文献   

9.
Both supply and demand side changes are necessary to achieve a sustainable food system. However, the weight accorded to these depends on one’s view of what the priority goals are for the food system and the extent to which production systems versus consumption patterns are open to change. Some stakeholders see the problem as one of ‘not enough food’ and focus on the need to sustainably increase supply, while others consider the resource demanding and ‘greedy’ consumption patterns of the Western world as the main problem and emphasize the need to shift diets. In this study global land use and greenhouse gas emissions are estimated for a set of scenarios, building on four ‘livestock futures’ reflecting these different perspectives. These scenarios are: further intensification of livestock systems; a transition to plant-based eating; a move towards artificial meat and dairy; and a future in which livestock production is restricted to the use of ‘ecological leftovers’ i.e. grass from pastures, food waste and food and agricultural byproducts. Two dietary variants for each scenario are modelled: 1) a projected diet following current trends and 2) a healthy diet with more fruits and vegetables and fewer animal products, vegetable oils and sugar. Livestock production in all scenarios (except the baseline scenario) was assumed to intensify to current levels of intensive production in North-Western Europe. For each scenario, several variant assumptions about yield increases and waste reductions were modelled. Results show that without improvements in crop productivity or reductions on today’s waste levels available cropland will only suffice if production of all protein currently supplied by animal foods is replaced by (hypothetical) artificial variants not requiring any land. With livestock intensities corresponding to current ones in North-Western Europe and with yield gaps closed by 50% and waste reduced by 50%, available cropland will suffice for all scenarios that include a reduction of animal products and/or a transition to poultry or aquaculture. However, in the scenario based on an extrapolation of current consumption patterns (animal product amounts and types consumed in proportions corresponding to the current average consumption in different world regions) and with livestock production based on feed from cropland, available cropland will not be enough. The scenario that makes use of pastures for ruminant production and food waste for pigs, uses considerably less cropland and could provide 40–56 kg per capita per year of red meat. However, such a livestock future would not reduce GHG emissions from agriculture on current levels. This study confirms previous research that to achieve a sustainable food future, action is needed on all fronts; improved supply and reduced demand and waste.  相似文献   

10.
Human appropriation of land for food production has fundamentally altered the Earth system, with impacts on water, soil, air quality, and the climate system. Changes in population, dietary preferences, technology and crop productivity have all played important roles in shaping today’s land use. In this paper, we explore how past and present developments in diets impact on global agricultural land use. We introduce an index for the Human Appropriation of Land for Food (HALF), and use it to isolate the effects of diets on agricultural land areas, including the potential consequences of shifts in consumer food preferences. We find that if the global population adopted consumption patterns equivalent to particular current national per capita rates, agricultural land use area requirements could vary over a 14-fold range. Within these variations, the types of food commodities consumed are more important than the quantity of per-capita consumption in determining the agricultural land requirement, largely due to the impact of animal products and in particular ruminant species. Exploration of the average diets in the USA and India (which lie towards but not at global consumption extremes) provides a framework for understanding land use impacts arising from different food consumption habits. Hypothetically, if the world were to adopt the average Indian diet, 55% less agricultural land would be needed to satisfy demand, while global consumption of the average USA diet would necessitate 178% more land. Waste and over-eating are also shown to be important. The area associated with food waste, including over-consumption, given global adoption of the consumption patterns of the average person in the USA, was found to be twice that required for all food production given an average Indian per capita consumption. Therefore, measures to influence future diets and reduce food waste could substantially contribute towards global food security, as well as providing climate change mitigation options.  相似文献   

11.
Western diets are characterised by a high intake of meat, dairy products and eggs, causing an intake of saturated fat and red meat in quantities that exceed dietary recommendations. The associated livestock production requires large areas of land and lead to high nitrogen and greenhouse gas emission levels. Although several studies have examined the potential impact of dietary changes on greenhouse gas emissions and land use, those on health, the agricultural system and other environmental aspects (such as nitrogen emissions) have only been studied to a limited extent. By using biophysical models and methods, we examined the large-scale consequences in the European Union of replacing 25–50% of animal-derived foods with plant-based foods on a dietary energy basis, assuming corresponding changes in production. We tested the effects of these alternative diets and found that halving the consumption of meat, dairy products and eggs in the European Union would achieve a 40% reduction in nitrogen emissions, 25–40% reduction in greenhouse gas emissions and 23% per capita less use of cropland for food production. In addition, the dietary changes would also lower health risks. The European Union would become a net exporter of cereals, while the use of soymeal would be reduced by 75%. The nitrogen use efficiency (NUE) of the food system would increase from the current 18% to between 41% and 47%, depending on choices made regarding land use. As agriculture is the major source of nitrogen pollution, this is expected to result in a significant improvement in both air and water quality in the EU. The resulting 40% reduction in the intake of saturated fat would lead to a reduction in cardiovascular mortality. These diet-led changes in food production patterns would have a large economic impact on livestock farmers and associated supply-chain actors, such as the feed industry and meat-processing sector.  相似文献   

12.
Global and regional trends in greenhouse gas emissions from livestock   总被引：2，自引：0，他引：2  
Following IPCC guidelines (IPCC 2006), we estimate greenhouse gas emissions related to livestock in 237 countries and 11 livestock categories during the period 1961–2010. We find that in 2010 emissions of methane and nitrous oxide related to livestock worldwide represented approximately 9 % of total greenhouse gas (GHG) emissions. Global GHG emissions from livestock increased by 51 % during the analyzed period, mostly due to strong growth of emissions in developing (Non-Annex I) countries (+117 %). In contrast, developed country (Annex I) emissions decreased (?23 %). Beef and dairy cattle are the largest source of livestock emissions (74 % of global livestock emissions). Since developed countries tend to have lower CO2-equivalent GHG emissions per unit GDP and per quantity of product generated in the livestock sector, the amount of wealth generated per unit GHG emitted from the livestock sector can be increased by improving both livestock farming practices in developing countries and the overall state of economic development. Our results reveal important details of how livestock production and associated GHG emissions have occurred in time and space. Discrepancies with higher tiers, demonstrate the value of more detailed analyses, and discourage over interpretation of smaller-scale trends in the Tier 1 results, but do not undermine the value of global Tier 1 analysis.  相似文献   

13.
Responsible water management in an era of globalised supply chains needs to consider both local and regional water balances and international trade. In this paper, we assess the water footprints of total final demand in the EU-27 at a very detailed product level and spatial scale—an important step towards informed water policy. We apply the multi-regional input-output (MRIO) model EXIOBASE, including water data, to track the distribution of water use along product supply chains within and across countries. This enables the first spatially-explicit MRIO analysis of water embodied in Europe’s external trade for almost 11,000 watersheds world-wide, tracing indirect (“virtual”) water consumption in one country back to those watersheds where the water was actually extracted. We show that the EU-27 indirectly imports large quantities of blue and green water via international trade of products, most notably processed crop products, and these imports far exceed the water used from domestic sources. The Indus, Danube and Mississippi watersheds are the largest individual contributors to the EU-27’s final water consumption, which causes large environmental impacts due to water scarcity in both the Indus and Mississippi watersheds. We conclude by sketching out policy options to ensure that sustainable water management within and outside European borders is not compromised by European consumption.  相似文献   

14.
Over the last three decades, socio-economic, demographic and technological transitions have been witnessed throughout the world, modifying both sectorial and geographical distributions of greenhouse gas (GHG) emissions. Understanding these trends is central to the design of current and future climate change mitigation policies, requiring up-to-date methodologically robust emission inventories such as the Emissions Database for Global Atmospheric Research (EDGAR), the European Commission’s in-house, independent global emission inventory. EDGAR is a key tool to track the evolution of GHG emissions and contributes to quantifying the global carbon budget, providing independent and systematically calculated emissions for all countries.According to the results of the EDGAR v.5.0 release, total anthropogenic global greenhouse gas emissions (excluding land use, land use change and forestry) were estimated at 49.1 Gt CO2eq in 2015, 50 % higher than in 1990, despite a monotonic decrease in GHG emissions per unit of economic output. Between 1990 and 2015, emissions from developed countries fell by 9%, while emissions from low to medium income countries increased by 130%, predominantly from 2000 onwards. The 27 Member States of the European Union and the United Kingdom led the pathway for emission reductions in industrialised economies whilst, in developing countries, the rise in emissions was driven by higher emissions in China, India, Brazil and nations in the South-East Asian region. This diversity of patterns shows how different patterns for GHG emissions are and the need for identifying regionally tailored emission reduction measures.  相似文献   

15.
《Climate Policy》2002,2(2-3):197-209
Korea, straddled between developing and developed country status, is facing challenges and opportunities in energy use and climate change mitigation potential. Unlike other OECD countries, Korea’s greenhouse gas (GHG) emissions are expected to continue to grow for the next two decades. The responses Korea could take to lower emissions without hampering economic development have an important bearing on the global response to climate change. This paper summarizes and evaluates mitigation strategies and major options for Korea in the energy sector, a major contributor to GHG emissions.  相似文献   

16.
《Climate Policy》2013,13(2-3):197-209
Abstract

Korea, straddled between developing and developed country status, is facing challenges and opportunities in energy use and climate change mitigation potential. Unlike other OECD countries, Korea's greenhouse gas (GHG) emissions are expected to continue to grow for the next two decades. The responses Korea could take to lower emissions without hampering economic development have an important bearing on the global response to climate change. This paper summarizes and evaluates mitigation strategies and major options for Korea in the energy sector, a major contributor to GHG emissions.  相似文献   

17.
Reliable estimates of carbon and other environmental footprints of agricultural commodities require capturing a large diversity of conditions along global supply chains. Life Cycle Assessment (LCA) faces limitations when it comes to addressing spatial and temporal variability in production, transportation and manufacturing systems. We present a bottom-up approach for quantifying the greenhouse gas (GHG) emissions embedded in the production and trade of agricultural products with a high spatial resolution, by means of the integration of LCA principles with enhanced physical trade flow analysis. Our approach estimates the carbon footprint (as tonnes of carbon dioxide equivalents per tonne of product) of Brazilian soy exports over the period 2010–2015 based on ~90,000 individual traded flows of beans, oil and protein cake identified from the municipality of origin through international markets. Soy is the most traded agricultural commodity in the world and the main agricultural export crop in Brazil, where it is associated with significant environmental impacts. We detect an extremely large spatial variability in carbon emissions across sourcing areas, countries of import, and sub-stages throughout the supply chain. The largest carbon footprints are associated with municipalities across the MATOPIBA states and Pará, where soy is directly linked to natural vegetation loss. Importing soy from the aforementioned states entailed up to six times greater emissions per unit of product than the Brazilian average (0.69 t t−1). The European Union (EU) had the largest carbon footprint (0.77 t t−1) due to a larger share of emissions from embodied deforestation than for instance in China (0.67 t t−1), the largest soy importer. Total GHG emissions from Brazilian soy exports in 2010–2015 are estimated at 223.46 Mt, of which more than half were imported by China although the EU imported greater emissions from deforestation in absolute terms. Our approach contributes data for enhanced environmental stewardship across supply chains at the local, regional, national and international scales, while informing the debate on global responsibility for the impacts of agricultural production and trade.  相似文献   

18.
印度应对气候变化国家方案简析   总被引：2，自引：0，他引：2       下载免费PDF全文
2008年6月印度政府发布了《气候变化国家行动方案》,阐明了印度应对气候变化的原则立场以及减缓和适应措施。方案中明确指出发展中国家是气候变化的最大受害者,发达国家应该承担温室气体减排的责任和义务;由于近年印度排放不断上升,方案也着重提出了提高能效、大力发展可再生能源等措施。与我国发布的《中国应对气候变化国家方案》进行对比,印度国家行动方案中的一些观点和措施值得我国研究和借鉴,该方案为我国进一步提出应对策略、加强国际合作提供了参考。  相似文献   

19.
We can generate a net global GHG emission reduction from developing countries (in an UNFCCC term, non-Annex 1 Parties) without imposing targets on them, if we discount CERs generated from CDM projects. The CER discounting scheme means that a part or all of CDM credits, i.e., CERs, made by developing countries through unilateral CDM projects will be retired rather than sold to developed countries to increase their emissions. It is not feasible to impose certain forms of target (whether sectoral or intensity targets) on non-Annex 1 whose emission trend is hard to predict and whose industrial structure is undergoing a rapid change.

Instead of imposing targets (a command and control approach), we should apply market instruments in generating a net global emission reduction from non-Annex 1. Since April 2005 when the first unilateral CDM was approved by the CDM Executive Board, CDM has been functioning as a market mechanism to provide incentives for developing countries to initiate their own emission reduction projects. As CDM is the only market mechanism engaging developing countries in the Kyoto Protocol, we should try to re-design CDM so that it can generate net global emission reductions by introducing the idea of discounting CERs. But in order to produce meaningful GHG emission reductions by discounting CERs, the project scope of CDM has to be expanded by relaxing project additionality criteria while maintaining strict technical additionality criteria. Agreeing on the CERs Discounting Scheme will have a better political chance than agreeing on imposing emission reduction targets on developing countries.  相似文献   

20.
Abstract

This article introduces and explores a new form of international commitment to limit greenhouse gas (GHG) emissions, called an action target. Action targets differ from other forms of targets, such as the Kyoto Protocol's fixed targets, in that they define a quantity of GHG abatement to be achieved, rather than a future emission level to be reached. This article explains the basic mechanics of how action targets might operate, and analyses the approach across a range of criteria, including uncertainty management and contributions to sustainable development in non-Annex I (developing) countries. The analysis suggests that action targets might improve the prospects of widening and deepening developing country participation in the international climate regime.  相似文献   

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