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1.
The rapid expansion of the production of agricultural commodities such as beef, cocoa, palm oil, rubber and soybean is associated with high rates of deforestation in tropical forest landscapes. Many state, civil society and market sector actors are engaged in developing and implementing innovative interventions that aim to enhance the sustainability of commodity supply chains by affecting where and how agricultural production occurs, particularly in relation to forests. These interventions – in the form of novel or moderated institutions and policies, incentives, or information and technology – can influence producers directly or achieve their impacts indirectly by influencing consumer, retailer and processor decisions. However, the evidence base for assessing the impacts of these interventions in reducing the negative impacts of commodity agriculture production in tropical forest landscapes remains limited, and there has been little comparative analysis across commodities, cases, and countries. Further, there is little consensus of the governance mechanisms and institutional arrangements that best support such interventions. We develop a framework for analyzing commodity supply chain interventions by different actors across multiple contexts. The framework can be used to comparatively analyze interventions and their impacts on commodity production with respect to the spatial and temporal scales over which they operate, the groups of supply chain actors they affect, and the combinations of mechanisms upon which they depend. We find that the roles of actors in influencing agricultural production depends on their position and influence within the supply chain; that complementary institutions, incentives and information are often combined; and that multi-stakeholder collaborations between different groups of actors are common. We discuss how the framework can be used to characterize different interventions using a common language and structure, to aid planning and analysis of interventions, and to facilitate the evaluation of interventions with respect to their structure and outcomes. Studying the collective experience of multiple interventions across commodities and spatial contexts is necessary to generate more systematic understandings of the impacts of commodity supply chain interventions in forest-agriculture landscapes.  相似文献   

2.
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   

3.
The production and trade of agricultural commodities, such as cocoa, have important impacts on farmer livelihoods and the environment, prompting a growing number of companies to adopt public commitments to address sustainability issues in their value chains. Though trading companies, who handle the procurement and export of these commodities, are key actors in corporate sustainability efforts, cross-country data on their identity, market share, and adoption of sustainability commitments is lacking. Here, we address this gap for the cocoa sector by compiling detailed shipping data from eight countries responsible for 80% of global cocoa exports, developing a typology of trader types, and assessing their adoption of sustainability commitments. We find that cocoa trading is a highly concentrated market: seven transnational companies handled 62% of the global cocoa trade, with even larger shares in individual cocoa producing countries. The remaining 38% of exports were handled by domestic trading companies and farmer cooperatives. Overall, the adoption of public sustainability commitments is low. We estimated that just over one quarter (26%) of cocoa is traded under some form of sustainability commitment, with gaps arising from their exclusion of indirect sourcing, low adoption rates by domestic traders, and commitment blind spots, notably on forest degradation and farmer incomes. Low rates of traceability and transparency pose a further barrier to the broadscale implementation and monitoring of these commitments: one-quarter of traders report being able to trace at least some of their cocoa back to farmer cooperatives and only half of them openly disclose the identity of their suppliers. We discuss the opportunities and limitations of voluntary sustainability commitments in a highly concentrated market and argue that, to realize visions of sustainable trade, the gaps in commitment coverage must be closed by extending current efforts to smaller traders and indirect suppliers. However, companies must support, coordinate and align with government efforts so that voluntary initiatives are ultimately rendered more transparent and accountable.  相似文献   

4.
Industrial phosphorus (P) fertilizer has substantially improved global food production, but has also led to environmental impacts. Intensive global agricultural trade has increased and the impacts of trade on aggravating or alleviating future P scarcity must be examined, especially for the most vulnerable countries. We combined data to estimate the global P trade among countries and its impacts on global P flows, based on global agricultural trade, cropland soil P budgets and crop P fertilizer footprints (the amount of industrial P fertilizer applied for producing one unit of P in the harvested crop). The global agricultural P trade represented a fraction of 16% of P in harvested crops in 2014, half of which was exported from the United States of America, Brazil and the European Union and one fifth imported by China. Virtual P fertilizer flows (about 2.60 Tg P y-1) referred to industrial P fertilizers applied to traded crops by exporting countries; thus, 1/3 of global virtual P fertilizer flows were associated with the international soybean trade. P use efficiency (PUE), the ratio of the harvested crop-P to the total external P inputs, is a larger problem for tropical than temperate countries. Global crop trade had brought in a net 0.2 Tg P y-1 savings of industrial P fertilizers globally, compared to crop production in export and import countries. >0.50 Tg y-1 of the gross global accumulation of soil P and P in freshwater were associated with global agricultural trade. Global PUE, however, could be improved considerably, and thus global cooperation and improving PUE could help to solve the problem of future P scarcity. Vulnerable countries should also propose urgent national plans to address their own situations of P scarcity or low PUE.  相似文献   

5.
This paper evaluates the role of trade as a mechanism of economic adjustment to the impacts of climate change on agriculture. The study uses a model of the world economy able to reflect changes in comparative advantage; the model is used to test the hypotheses that trade can assure that, first, satisfying global agricultural demand will not be jeopardized, and, second, general access to food will not decrease. The hypotheses are tested for three alternative scenarios of climate change; under each scenario, regions adjust to the climatic assumptions by changing the land areas devoted to agriculture and the mix of agricultural goods produced, two of the major mechanisms of agricultural adaptation. We find that trade makes it possible to satisfy the world demand for agricultural goods under the changed physical conditions. However, access to food decreases in some regions of the world. Other patterns also emerge that indicate areas of concern in relying on trade as a mechanism for the adjustment of agriculture to likely future changes in climate.  相似文献   

6.
Maintaining food security and environmental integrity over time requires a transition towards sustainable food systems. This paper analyzes different dimensions of national food supply sustainability on a global scale. By focusing on four food staples: wheat, rice, maize, and soybeans, the analysis identifies production regions that are more or less environmentally sustainable. It explores the dependence of different countries on calories supplied by these regions. These four staples' production requires 648 million hectares of cropland and about 559 cubic kilometers of irrigation water. It also leads to several environmental impacts, including potential soil loss and species loss. Yet, these impacts and pressures are spread unevenly across agricultural systems.We find that over one-third of the global calorie intake originates from regions with a high per ton environmental impacts. Although most consumed calories are from domestic sources, traded calories mostly originate from environmentally suitable production regions, increasing importing countries' food supply sustainability. This analysis also reveals interregional tradeoffs, where food imports into one region (increased food provision) is associated with high environmental impact in production regions. Further, this typology allows identifying an elusive, often overlooked interregional connection. That is the potential loss of future ecosystem service flow from countries with the lower gross domestic product per capita and high biodiversity. To date, those countries rely primarily on domestic staple production, which puts pressure on vulnerable local ecosystems. Species loss in those regions reduces the potential future interregional flows of genetic material. Alternatively, conservation combined with food imports can maintain diversity and the potential flow of genetic material from those regions. The functional regions typology provides a complete assessment of the interregional connections that make up the global food system. Therefore, it is useful for informing policy analysts and policymakers of a broader collection of stakeholders regarding the local environment. It also provides essential information about the suitability of different policy mechanisms to govern interregional systems. Future research shall expand the functional regions' typology to include additional environmental and human-related (e.g., technological), to cover more crops, and to account for other food categories, such as meat.  相似文献   

7.
与IPCC第五次评估报告相比,第六次评估报告(AR6)有关农业的评估对象由作物生产系统延伸到粮食供应链系统,气候变化对作物生产不利影响的证据在加强。气候变化改变了作物适宜种植区,使中高纬度及温带地区作物种植界限向高纬度、高海拔地区推移。人为引起的气候变暖阻碍了作物产量的增长,地表O3浓度增加使作物产量降低,CH4排放加剧了这种不利影响。气候变化加剧作物病虫草害,极端气候事件高发加剧了粮食不安全,推升了国际粮食价格。适应措施有助于减缓气候变化不利影响,基于自然的适应方案在增强作物生产系统气候恢复力和保障粮食安全方面具有较高潜力。从保障国家粮食安全和重大战略需求出发,AR6报告对我国农业应对气候变化相关工作的启示如下:需要高度重视气候变化背景下作物种植适宜区转变与种植带北移的重要战略价值,合理规划农业生产布局;加强农业气象灾害和病虫害防治体系和能力建设,保障粮食生产稳定性;关注气候变化对国际作物生产和谷物贸易的影响,统筹国内、国际市场粮食资源,保障粮食安全;推进农业温室气体减排与作物生产高效协同,为实现国家减排目标做出贡献。  相似文献   

8.
Agricultural land use to meet the demands of a growing population, changing diets, lifestyles and biofuel production is a significant driver of biodiversity loss. Globally applicable methods are needed to assess biodiversity impacts hidden in internationally traded food items. We used the countryside species area relationship (SAR) model to estimate the mammals, birds, amphibians and reptiles species lost (i.e. species ‘committed to extinction’) due to agricultural land use within each of the 804 terrestrial ecoregion. These species lost estimates were combined with high spatial resolution global maps of crop yields to calculate species lost per ton for 170 crops in 184 countries. Finally, the impacts per ton were linked with the bilateral trade data of crop products between producing and consuming countries from FAO, to calculate the land use biodiversity impacts embodied in international crop trade and consumption. We found that 83% of total species loss is incurred due to agriculture land use devoted for domestic consumption whereas 17% is due to export production. Exports from Indonesia to USA and China embody highest impacts (20 species lost at the regional level each). In general, industrialized countries with high per capita GDP tend to be major net importers of biodiversity impacts from developing tropical countries. Results show that embodied land area is not a good proxy for embodied biodiversity impacts in trade flows, as crops occupying little global area such as sugarcane, palm oil, rubber and coffee have disproportionately high biodiversity impacts.  相似文献   

9.
The United Nations’ Sustainable Development Goals (SDGs) are described as integrated and indivisible, where sustainability challenges must be addressed across sectors and scales to achieve global-level sustainability. However, SDG monitoring mostly focuses on tracking progress at national-levels, for each goal individually. This approach ignores local and cross-border impacts of national policies and assumes that global-level progress is the sum of national, sector-specific gains. In this study, we investigate effects of reforestation programs in China on countries supplying forest and agricultural commodities to China. Using case studies of rubber and palm oil production in Southeast Asian countries, soy production in Brazil and logging in South Pacific Island states, we investigate cross-sector effects of production for and trade to China in these exporting countries. We use a three-step multi-method approach. 1) We identify distal trade flows and the narratives used to justify them, using a telecoupling framework; 2) we design causal loop diagrams to analyse social-ecological processes of change in our case studies driven by trade to China and 3) we link these processes of change to the SDG framework. We find that sustainability progress in China from reforestation is cancelled out by the deforestation and cross-sectoral impacts supporting this reforestation abroad. Narratives of economic development support commodity production abroad through unrealised aims of benefit distribution and assumptions of substitutability of socio-ecological forest systems. Across cases, we find the analysed trade supports unambiguous progress on few SDGs only, and we find many mixed effects – where processes that support the achievement of SDGs exist, but are overshadowed by counterproductive processes. Our study represents a useful approach for tracking global-level impacts of national sustainability initiatives and provides cross-scale and cross-sectoral lenses through which to identify drivers of unsustainability that can be addressed in the design of effective sustainability policies.  相似文献   

10.
Like other animal production systems, aquaculture has developed into a highly globalized trade-dependent industry. A major part of aquaculture technology requires fishmeal to produce the feed for farmed species. By tracing and mapping patterns of trade flows globally for fishmeal we show the aquaculture industry's increasing use of marine ecosystems worldwide. We provide an in-depth analysis of the growth decades (1980–2000) of salmon farming in Norway and shrimp farming in Thailand. Both countries, initially net exporters of fishmeal, increased the number of import source nations of fishmeal, peaking in the mid-1990s. Thailand started locally and expanded into sources from all over the globe, including stocks from the North Sea through imports from Denmark, while Norway predominantly relied on northern region source nations to feed farmed salmon. In 2000, both have two geographically alternate sources of fishmeal supply: the combination of Chile and Peru in South America, and a regional complement. We find that fishmeal trade for aquaculture is not an issue of using ecosystems of the South for production in the North, but of trade between nations with industrialized fisheries linked to productive marine ecosystems. We discuss the expansion of marine ecosystem appropriation for the global aquaculture industry and observed shifts in the trade of fishmeal between marine areas over time. Globalization, through information technology and transport systems, has made it possible to rapidly switch between marine areas for fishmeal supply in economically connected food producing systems. But the stretching of the production chain from local to global and the ability to switch between marine areas worldwide seem to undermine the industry's incentives to respond to changes in the capacity of ecosystems to supply fish. For example, trade information does not reveal the species of fish that the fishmeal is made of much less its origins and there is lack of feedback between economic performance and impacts on marine ecosystem services. Responding to environmental feedback is essential to avoid the trap of mining the marine resources on which the aquaculture industry depends. There are grounds to suggest the need for some global rules and institutions that create incentives for seafood markets to account for ecosystem support and capacity.  相似文献   

11.
There is increasing interest in the water–food nexus, especially the restrictive effect of water on food production in hot spots where irrigation stress is growing. However, little is known about the larger-scale implications of future irrigation shortfalls for global trade and economic welfare, as well as of the potential buffering impacts of international trade on the local impacts of irrigation shortage. In this paper, we utilize a recently developed model, GTAP-BIO-W, to study the economic effects of changes in irrigation outlook for 126 river basins, globally by 2030. Projected irrigation availability is obtained from the IMPACT-WATER model, and imposed upon the present-day economy. Irrigation availability in 2030 is expected to drop by 30–60% in several key rivers basins, including: Hai He, Indus, Luni, and the Eastern Mediterranean basin, leading to significant output declines in China, South Asia, and the Middle East. We find that the regional production impacts of future irrigation water shortages are quite heterogeneous, depending on the size of the shortfall, the irrigation intensity of crop production, the possibility of expanding rainfed areas, as well as the crop mix. These changes in regional output significantly alter the geography of international trade. To compensate for the loss of productivity caused by the irrigation constraint, an estimated 7.6 million hectares of cropland expansion is needed to meet the demand for food. In spite of the remarkable reduction of irrigation in some basins, the resulting welfare impact is relatively modest as a result of the buffering capacity of global markets. The global welfare loss amounts to $3.7 billion (2001 prices) and results from a combination of the reduction in irrigation availability as well as the interplay with agricultural support policies.  相似文献   

12.
There is an increasing need for transformational changes in the global food system to deliver healthy nutritional outcomes for a growing population while simultaneously ensuring environmental sustainability. However, such changes are subject to political and public constraints that usually allow only gradual, incremental changes to occur. Drawing inspiration from the British cycling team’s concept of marginal gains, we show how transformation might be reconciled with incremental changes. We demonstrate that a set of marginal food system changes acting to increase production efficiency, to reduce losses or to adjust diets could collectively reduce the agricultural land required globally for food production by 21%, or over a third given higher adoption rates. The results show that while all categories of action are important, changes in consumer choices in Europe, North America and Oceania and in the supply-chain in Africa and West and Central Asia have the greatest potential to reduce the land footprint of the food system.  相似文献   

13.
This paper reviews historical and existing drought and water policy in Australia in order to gain a sense of the strengths and weaknesses in enabling effective adaptation to climate change. In particular, (a) the social, economic, and environmental costs and benefits of water trading and (b) the limitations of using ‘market-based’ instruments (MBIs), like water trading, for adapting to drought and water security related climate change impacts are investigated. It was found that water trading has potential as a climate change adaptation strategy with many benefits experienced in previous and current versions of water trading. However, there are also limitations and those negatively impacted by water trading are hit hard. These social impacts of water trading have not been thoroughly investigated and are not well understood. Significant uncertainty also exists around the impacts of water trading on the environment (e.g. changed hydrological regimes, underestimation of sustainable environmental flows etc.). Proper quantification of these impacts is needed, however, it is a complex task given Australia's large hydroclimatic variability and the current lack of understanding as to how to optimise water needs of the environment, humans, agriculture and other industries. It appears that ‘cap and trade’ quantity-based MBIs such as water trading will eventually do what they are designed to do (i.e. reallocate a resource to ‘high value’ users). However, given that the ‘low value’ users in this case are agriculture and town/urban water supply (not including drinking water) and the ‘high value’ users are mining, manufacturing, and electricity production (i.e. high greenhouse gas emissions), do we really want the water trading MBI to achieve its objective? And, what would the social and environmental ramifications of such a shift in water use within Australia be? These questions, along with the limitations and potential implications of using water trading (and MBIs in general) as a climate change adaptation tool, must be carefully considered if past Australian drought and water policy failures are not to be repeated.  相似文献   

14.
The global use of and pressure on land resources will continue to rise in tandem with the predicted rise in global population and food demand. Addressing unavoidable trade-offs between satisfying human needs and biodiversity conservation for future generations is of paramount importance when tackling the global environmental challenges of land use. Food consumption patterns are inextricably linked to land-use and land-use changes. The domestic supply and final use of food by humans and feed by animals within the borders of a country have environmental impacts overseas. Countries like Denmark, with considerably high livestock production, import “virtual” land needed to produce cereals and other fodder crops. Denmark's high meat and dairy consumption and trade levels make it a compelling case for this study. The overarching question is: how much land is required to support food and feed consumption in Denmark? This paper assesses the global cropland footprint of Danish food and feed supply from 2000 to 2013 using a consumption-based physical accounting approach. In addition to domestic croplands for local food and supply, we estimate the hectares of cropland displaced in other countries to satisfy Danish demand for food and feed in this period. Secondly, we calculate Denmark's global cropland requirements for the supply of specific livestock products, namely; pork, eggs, beef, milk, and mutton. Globally, animals provide a third of the protein in human diets and agricultural GDP. The total global cropland footprint of Danish food and feed supply decreased by 18% from 1568 kha in 2000 to 1282 kha in 2013 because of a reduction in the consumption of ruminant livestock products. A high share of this reduction can be attributed to increased local self-sufficiency in feed supply as opposed to rising food imports. The share of cropland used for feed in total cropland declined by 5% whereas the share of cropland used for food increased from 28% in 2000 to 32% by 2013. Our findings suggest that reducing domestic meat consumption coupled with local self-sufficiency policies for both food and feed supply could be a means of lowering ecological degradation in exporting countries.  相似文献   

15.
IPCC特别报告SRCCL关于气候变化与粮食安全的新认知与启示   总被引:3,自引:0,他引:3  
气候变化对粮食安全的影响是广泛的,不但影响粮食产量和品质,还会影响到农户的生计以及农业相关的产业发展等;而粮食系统在保障粮食安全的同时,又会产生一系列的环境问题,其中农业源温室气体(GHG)的排放加剧全球变暖。IPCC在2019年8月份发布的《气候变化与土地特别报告》(SRCCL),从粮食生产、加工、储存、运输及消费的各个环节评估气候变化对粮食安全的影响及粮食系统的温室气体排放对气候系统的影响;系统梳理粮食系统供给侧和需求侧的适应与减缓措施、适应与减缓的协同和权衡问题,以及气候变化条件下保障粮食安全的政策环境等。SRCCL评估结论认为,由于大量施用氮肥和消耗水资源,目前粮食系统GHG排放占全球总排放的21%~37%;农业和粮食系统是全球应对气候变化的重要方面,供给侧和需求侧的综合措施可以减少食物浪费、减少GHG排放、增加粮食系统的恢复力。未来工作的重点应丰富和扩展气候变化影响评估内容,量化适应效果,加深对适应、减缓及其协同和权衡的科学认知,大力加强应对气候变化能力建设。  相似文献   

16.
This study explores the effects of agricultural trade liberalisation and concomitant changes in agricultural areas and livestock production on greenhouse gas emissions using the coupled LEITAP–IMAGE modelling system. The results indicate that liberalisation leads to an increase in total greenhouse gas emissions by about 6% compared to the reference scenario value in 2015. The increase in CO2 emissions are caused by vegetation clearance due to a rapid expansion of agricultural area; mainly in South America and Southeast Asia. Increased methane emissions in the case of full liberalisation are caused by less intensive cattle farming in regions such as South America and Southeast Asia. This pattern is observed up to 2050. Total global production of milk, dairy and beef do not change with full liberalisation, but production shifts were observed from North America and Europe to South America and Southeast Asia. Results are less pronounced in variants where trade liberalisation is only implemented partially. Remarkably, our study shows in the trade barrier removal scenario larger numbers of dairy cows in Australia and New Zealand (ANZ) then with full liberalisation scenario or a variant in which only milk quota are abolished. This illustrates that different types of liberalisation need to be analysed regionally and per commodity before general conclusions on the impact of trade liberalisation can be drawn. Our study contributes new information on greenhouse gas emissions to a vast number of trade liberalisation studies that focus on economic impacts. The combined economic-environmental impacts need to be assessed in detail before general conclusions on trade liberalisation can be given.  相似文献   

17.
Human activities use more than half of accessible freshwater, above all for agriculture. Most approaches for reconciling water conservation with feeding a growing population focus on the cropping sector. However, livestock production is pivotal to agricultural resource use, due to its low resource-use efficiency upstream in the food supply chain. Using a global modelling approach, we quantify the current and future contribution of livestock production, under different demand- and supply-side scenarios, to the consumption of “green” precipitation water infiltrated into the soil and “blue” freshwater withdrawn from rivers, lakes and reservoirs. Currently, cropland feed production accounts for 38% of crop water consumption and grazing involves 29% of total agricultural water consumption (9990 km3 yr−1). Our analysis shows that changes in diets and livestock productivity have substantial implications for future consumption of agricultural blue water (19–36% increase compared to current levels) and green water (26–69% increase), but they can, at best, slow down trends of rising water requirements for decades to come. However, moderate productivity reductions in highly intensive livestock systems are possible without aggravating water scarcity. Productivity gains in developing regions decrease total agricultural water consumption, but lead to expansion of irrigated agriculture, due to the shift from grassland/green water to cropland/blue water resources. While the magnitude of the livestock water footprint gives cause for concern, neither dietary choices nor changes in livestock productivity will solve the water challenge of future food supply, unless accompanied by dedicated water protection policies.  相似文献   

18.
Fish resources are critical to the food security of many nations. Similar to most contemporary food systems, many fisheries and aquaculture resource supply chains are heavily dependent on fossil fuels. Energy price increases and volatility may hence undermine food security in some contexts. Here, we explore the relationships between energy price changes, fish resource supply chain viability, seafood availability and food security outcomes – both for producers and consumers of fish resources. We begin by characterizing the energy intensities of fish resource supply chains, which are shown to be highly variable. We subsequently assess the comparative magnitude and distribution of potential food security impacts of energy price increases for nation states by scoring and ranking countries against a set of vulnerability criteria including metrics of national exposure, sensitivity and adaptive capacity. Considerable variability in the vulnerability of populations and high levels of exposure for already food-insecure populations are apparent. Developed countries are likely to be most exposed to the effects of energy price increases due to their high rates of fleet motorization and preference for energy-intensive seafood products. However, heavy reliance on seafood as a source of food and income, as well as limited national adaptive capacity, translates into greater overall vulnerability in developing countries. At the level of individual producers, a variety of adaptation options are available that may serve to reduce vulnerability to energy price changes and hence contribute to increased food security for producers and consumers, but uptake capacity depends on numerous situational factors.  相似文献   

19.
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   

20.
Climate change impacts food production systems, particularly in locations with large, vulnerable populations. Elevated greenhouse gases (GHG), as well as land cover/land use change (LCLUC), can influence regional climate dynamics. Biophysical factors such as topography, soil type, and seasonal rainfall can strongly affect crop yields. We used a regional climate model derived from the Regional Atmospheric Modeling System (RAMS) to compare the effects of projected future GHG and future LCLUC on spatial variability of crop yields in East Africa. Crop yields were estimated with a process-based simulation model. The results suggest that: (1) GHG-influenced and LCLUC-influenced yield changes are highly heterogeneous across this region; (2) LCLUC effects are significant drivers of yield change; and (3) high spatial variability in yield is indicated for several key agricultural sub-regions of East Africa. Food production risk when considered at the household scale is largely dependent on the occurrence of extremes, so mean yield in some cases may be an incomplete predictor of risk. The broad range of projected crop yields reflects enormous variability in key parameters that underlie regional food security; hence, donor institutions’ strategies and investments might benefit from considering the spatial distribution around mean impacts for a given region. Ultimately, global assessments of food security risk would benefit from including regional and local assessments of climate impacts on food production. This may be less of a consideration in other regions. This study supports the concept that LCLUC is a first-order factor in assessing food production risk.  相似文献   

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