Footprints of water and energy inputs in food production – Global perspectives

During the second half of the 20th century the global food production more than doubled and thus responded to the doubling of world population. But the gains in food production came at a cost, leaving a significant environmental footprint on the ecosystem. Global cropland, plantations and pastures expanded, with large increases in fossil energy, water, and fertilizer inputs, imprinting considerable footprint on the environment. Information from pre eminent publications such as Nature, Science, PNAS and scholarly journals is synthesized to assess the water and energy footprints of global food production. The data show that the footprints are significant, both locally, national and globally and have consequences for global food security and ecosystem health and productivity. The literature nearly agrees that global food production system generates considerable environmental footprints and the situation would likely get worrisome, as global population grows by 50% by 2050. Investments are needed today to buffer the negative impacts of food production on the environment. Investments to boost water productivity and improve energy use efficiency in crop production are two pathways to reduce the environmental footprint.     

Comparing environmental impacts of regional and national-scale food supply chains: A case study of processed tomatoes

This study uses life cycle assessment methodology to quantify the energy use, greenhouse gas (GHG) emissions, and water use of processed tomato products grown, processed, and consumed within the Great Lakes region of the United States, and tomato products produced in California and then shipped to the Great Lakes region for consumption. The purpose is to assess the potential for regional food systems to reduce selected environmental impacts, particularly the energy and GHG footprints, of consumer-ready, processed food products, when compared to national-scale food systems in which consumer products are shipped long distances. The study also examines the role of different types of food processing in influencing life cycle energy use, water use, and emissions.Our results indicate that California-produced conventional and organic tomato paste and canned diced tomatoes are almost equivalent in energy use and GHG emissions to regionally produced and consumed products, but use of developed water resources is significantly higher for California-grown products. California tomato production benefits from higher per hectare yields and soil amendments with lower carbon dioxide emissions. These efficiencies substantially offset the added energy use and GHG emissions associated with long-distance shipment of products to the Great Lakes region, as long as shipments are made by rail rather than by truck. Paste, the more processed and concentrated product evaluated, amplifies any environmental advantages or disadvantages accrued in the field production stage, due to its raw tomato to finished product ratio of 6:1, suggesting that comparative regional advantage can play a role in lowering life cycle environmental impacts of highly condensed foods shipped long distances.     

Protein efficiency per unit energy and per unit greenhouse gas emissions: Potential contribution of diet choices to climate change mitigation

The production, transport and processing of food products have significant environmental impacts, some of them related to climate change. This study examined the energy use and greenhouse gas emissions associated with the production and transport to a port in Sweden (wholesale point) of 84 common food items of animal and vegetable origin. Energy use and greenhouse gas (GHG) emissions for food items produced in different countries and using various means of production were compared. The results confirmed that animal-based foods are associated with higher energy use and GHG emissions than plant-based foods, with the exception of vegetables produced in heated greenhouses. Analyses of the nutritional value of the foods to assess the amount of protein delivered to the wholesale point per unit energy used or GHG emitted (protein delivery efficiency) showed that the efficiency was much higher for plant-based foods than for animal-based. Remarkably, the efficiency of delivering plant-based protein increased as the amount of protein in the food increased, while the efficiency of delivering animal-based protein decreased. These results have implications for policies encouraging diets with lower environmental impacts for a growing world population.     

Global water crisis and future food security in an era of climate change

Food policy should serve humanity by advancing the humane goals of eradicating extreme poverty and hunger. However, these goals have recently been challenged by emerging forces including climate change, water scarcity, the energy crisis as well as the credit crisis. This paper analyses the overall role of these forces and population growth in redefining global food security. Specifically, global water supply and demand as well as the linkages between water supply and food security are examined. The analysis reveals that the water for food security situation is intricate and might get daunting if no action is taken. Investments are needed today for enhancing future food security; this requires action on several fronts, including tackling climate change, preserving land and conserving water, reducing the energy footprint in food systems, developing and adopting climate resilient varieties, modernising irrigation infrastructure, shoring up domestic food supplies, reforming international food trade, and responding to other global challenges.     

Energy systems analysis for food policy

Recent work on energy systems analysis of food production systems has demonstrated the importance of energy to the food production sector of the economy. We show how energy requirements for food production are closely related to the intensity of production, and that there is a quantifiable trade-off between land and energy use. This trade-off is quite different for vegetable and industrial food as opposed to animals and fish. Thus the energy consequences to food production from changes in diet, shrinking land resources or increasing population may be readily computed.     

The effect of spatial variables on the economic and environmental performance of bioenergy production chains

The aim of this paper is to understand the impacts of spatial variables on the performance of bioenergy production chains (BPCs). Even though the strong debates continue on the use of first generation biomass for bioenergy production, many countries continue to utilize it as an alternative energy source. Several studies have been carried out on biomass transformation efficiency, on environmental impacts of using crop in biofuel production, and on its negative effects on increasing food prices. However, less attention has been paid to the role played by the spatial variables on the performance measures of BPCs.In this paper, we analyse how three spatial variables, i.e. cultivation area size, land dispersion, and accessibility to cultivation areas, can affect the performance of energy-balanced BPC, which produces its own electric and thermal energy demand. The chain is represented as a network of processes, where all inputs and outputs are geographically referred and analysed in a theoretical case example. We propose an enterprise input-output (EIO) model, which can be used as an accounting tool to compute the main materials and energy flows-related costs and as a planning tool to evaluate the chain performance in different scenarios. Finally, the proposed model is applied to an actual case study, to investigate the opportunity to establish a sunflower-based BPC in Apulia region (Italy) and to assess its performance.Results show that higher land dispersion degree and less area accessibility levels reduce the economic and environmental performance of the BPCs. The construction of the energy-balanced chain reduces the negative environmental impacts caused by fossil energy use in the processes of the BPC. Managerial implications can also be obtained from actual case study about the biodiesel plant location decisions.     

Impact of water scarcity in Australia on global food security in an era of climate change

Australia is a major food exporting country. Recent droughts reduced dryland farming production and the volume of water allocated to irrigated agriculture, with a resulting decline in aggregate agricultural production and exports. This paper analyses the possible impact of increased water scarcity on Australian agricultural production and the magnitude of subsequent impacts on global food security. Using the Australian Bureau of Statistics (ABS) data on land and water use coupled with a hydro-economic stochastic modelling approach, the impacts of reduced agricultural production in the southern Murray–Darling Basin, and more generally for Australia, are analysed. Changes in agricultural activity, reduction in agricultural exports and altered composition of products exported attributed to the severe 2000–2009 drought are also analysed to highlight the implications for global food security. The impact of climate change on food production is examined. The analysis shows that climate change, when modelled as the extreme case, along with other factors such as land use, will impact Australian food exports. Despite its relatively small contribution to total global food supply, Australia’s contribution to international trade in wheat, meat and dairy products is substantial and could affect global food prices. Furthermore, Australia’s agricultural exports are of disproportionate importance within the South- and South–East Asian and Oceania region, both in terms of volume and for strategic reasons. Adaptation along with investment in agriculture production is needed to maintain Australian agricultural production and enhance global food security.     

The new competition for land: Food,energy, and climate change

The paper addresses the new competition for land arising from growing and changing demand for food when combined with increasing global demand for transport energy, under conditions of declining petro-chemical resources and the urgent need to reduce greenhouse gas emissions. The paper starts from the premise of a ‘food, energy and environment trilemma’ (Tilman et al., 2009), where all demands to expand the area of cultivated land present high risks of increasing the carbon footprint of agriculture. Having reviewed the main drivers of demand for food and for liquid transport fuels, the paper weighs the controversies surrounding biofuels arising from food-price spikes, the demand for land, and consequent direct and indirect land-use change. It suggests that we need a more complex, and geographically differentiated, analysis of the interactions between direct and indirect land-use change. The paper then reviews evidence of land availability, and suggests that in addition to technical availability in terms of soil, water, and climate, political, social, and technological factors have significantly shaped the competition for land in different global regions, particularly the three major biofuel producing ones of the USA, Brazil and Europe. This point is further developed by reviewing the different innovation pathways for biofuels in these three regions. The main conclusion of this review is firstly that any analysis requires an integrated approach to the food-energy-environment trilemma, and secondly that strategic political direction of innovation and sustainability regulation are required to bring about major shifts in agriculture leading to sustainable intensification of cultivation (Royal Society, 2009), rather than the continued expansion of cultivated area. The consequent perspective is one of considerable global variety in technologies, agricultural productive systems, and use of natural resources. This contrasts sharply with the world of a dominant global and integrated technology platform based on petro-chemicals to which we have become accustomed.     

Changes in human nutrition and US exports

Changes in US nutrition could increase the availability of grains for world food use. This study examines such changes by means of a programming model which allows an optimal inter-regional allocation of grains while simultaneous shifts are made in consumer diets. The three alternatives examined include use of added US production potential for wheat production and exports, a substitution of 25% soy protein for meat and reducing the animal protein intake by 25%. Sizable increases in food exports could be made under each of the three alternatives. Of course, institutional means would need to be created to facilitate these shifts.     

Challenging the food vs. fuel dilemma: Genealogical analysis of the biofuel discourse pursued by international organizations

This paper looks critically at how food and agriculture-, energy security-, and climate change-oriented international organizations have consolidated and modified the biofuel discourse in relation to the agricultural system. Using Foucault-based genealogical analysis of discursive formations, the paper traces the last 20 years of institutions’ biofuel debate in relation to rural production. We find that the prevalent motive is an aspiration to combine the agriculture and energy markets into one, which prompts structural changes and challenges in the rural sector. This has implications for the future role and shape of global agriculture and – contrary to the food vs. fuel perspective – calls for re-conceptualizing the biofuel debate as the food vs. food dilemma.     

我国风力发电的环境价值分析

风能是一种可再生能源,在当前能源短缺的时代扮演了重要角色。考虑量化风力发电的环境价值,提出风电环境价值的构成,并选取相关指标,运用环境经济学相关理论对风电的环境价值进行评估。风力发电环境价值的测算是相对于常规煤电的。为了量化风力发电在减少环境污染方面的作用,先对火电厂主要污染物的排放量进行计算,然后制定各主要污染物的环境价值标准,最后以500MW火电厂为参照,计算我国风力发电的环境价值,其结果为0．1491元／（kW·h）,而我国天然气发电的环境价值仅为0．0896元／（kW·h）,相比之下,我国风力发电的环境效益相当显著。     

International trade related food miles – The case of Canada

At the beginning of the 21st century imports of agricultural and food commodities have become a major part of many nations’ food baskets. Indeed the global food system has several merits for nations, businesses and individual consumers’ well-being. However, as increasing evidence suggests that we are approaching an era of climate change and scarcity of cheap energy sources the sustainability of that system must be examined. One part of any food commodity chain is its ‘food miles’ – the distance the commodity travels from point of production to point of consumption, the required energy and resulting emissions. This paper presents a 1 year ‘snapshot’ of Canada’s total import related food miles. It presents an analysis of the distance imported foods traveled from around the world to major points of consumption in Canada and documents the equivalent carbon dioxide emissions related to those imports. It presents both a macro scale picture of the equivalent emissions related to transportation of imported food and a micro scale picture which focuses on specific commodities consumed in various parts of the country. It then discusses policy implications for food sustainability. Overall the research highlights that about 30% of the agricultural and food commodities consumed in Canada are imported, resulting in ‘food miles’ of over 61 billion tonnes km, leading to annual emissions of 3.3 million metric tonnes of CO₂. Of the various agriculture and food commodities studied, fruits and vegetables had the highest food miles related emissions.     

基于“节能减排”的投入产出模型研究

节约能源和减少排放是我国实施科学发展观的一项重大举措,它关系到国民经济的持续、健康发展。而已有投入产出模型是将节能和减排分别研究的,研究节能编制能源投入产出模型,研究减排编制环境投入产出模型。本文试图将节能和减排同时纳入投入产出分析框架,研制基于节能减排的投入产出模型,即设计能源、环境、经济投入产出表和模型体系。主要工作是将原有的经济投入产出表的中间投入分成三部分,即其他投入、能源投入、环境投入,再将未达标排放的虚拟费用从增加值中扣除放入环境投入中。这样,原有投入产出表的第Ⅰ、Ⅱ象限均分成其他产品、能源产品、环境产品三部分,第Ⅲ象限为调整增加值。该模型可从调整产业结构的层面研究节能减排问题。     

Towards a food and nutrition policy for Australia,an environmentalist view

The state government of Victoria, Australia, recently prepared a discussion paper towards a regional food and nutrition policy. This evaluation finds it deficient in various ways. The critique contains recommendations for the building of a national food policy. The commission report displays a lack of a systems view of the problem of nutrition, which would recognize a diversity of influences on eating (e.g. social frameworks and frameworks by which we think and know). Linear causality is not an adequate concept. Agribusiness impacts heavily on the environment. In the case of meat production, inputs to production far exceed food energy outputs. Disposal of the by-products of meat production is also more problematic. The way to impact on these wasteful and destructive industrial practices is to consume less meat. Additives in food are a serious problem not well enough addressed. This and other processing increase the cultural perception of foodstuffs as human artifacts. Awareness of the cultural role of foods would allow Australians to cope with industry campaigns promoting meat and processed foodstuffs. There should be more attention to mutual impacts of environment, consumptiuon, and additives and processing. Food from low in the food chain (cereals, seafood) should be promoted not as substitutes but as foods in their own right. Commission recommendations should deal with questions such as nutritional information labeling of foods, and especially an attempt to foster consciousness of the environmental impact of food consumption: Government policy should be mindful to the extent possible of the impact on poor areas of the world of wasteful food consumption in Australia. Proposals for action should benefit from the impact of several fields of expertise beyond health, agriculture, consumer affairs and others; for instance, anthropology or environmental science.     

Supplying vegetables to Asian cities: is there a case for peri-urban production?

In this paper, we analyse the dynamic interplay between peri-urban vegetable producers and their changing production and marketing environments in Asia, using examples from urban conglomerates in South, Southeast and East Asia. We discuss income generation, labour use, management of land and water resources, use of urban and market waste materials and health and food safety aspects. We conclude that peri-urban vegetable production, even though currently economically viable, is unlikely to be able to compete in the long run for scarce land and labour resources, unless alternative production technologies become available and the positive externalities generated by peri-urban agriculture become internalised. There is thus an urgent need for interdisciplinary research aimed at developing such technologies as well as for integrated economic and environmental analyses that take explicit account of interactions between peri-urban producers, the urban waste management sector, municipal planners and consumers.     

灰色预测模型在陕西省电力消费量预测中的应用

电力消费是人们日常生活必不可少的,随着城市的大力发展,有效地对电力消费进行预测显得越来越重要。本文采用灰色预测模型GM(1,1),建立陕西省电力消费量预测GM(1,1)模型,验证预测精度,进一步对2011-2015年陕西省的电力消费量进行预测,为今后陕西省的电力规划提供参考价值。     

Energy and irrigation in LDCs

Climatic conditions prevailing in most developing countries determine that much of the annual rainfall is seasonal. There are regular dry spells which last anything from a few weeks to several months and sometimes even longer. If developing countries are to achieve greater self-sufficiency in food production, then irrigation must play a vital role. But irrigation is energy intensive and some energy sources are a dwindling asset. On the other hand there is a continually rising demand for food which automatically produces a corresponding increase in energy requirements. The question this poses then is, if continuity of food production is to be assured, on what energy system should irrigation development be based? Alternatively, how can expendable sources of energy be most economically used?     

节能投资新机制：合同能源管理

节能减排是当今世界降低能源消耗、控制环境污染的主要方法,也是世界各国的重要责任。合同能源管理作为一种先进的能源管理模式和市场化运作的节能新机制,在我国已有近10年的发展历程,取得了良好的节能效果。介绍了合同能源管理的运作模式,结合我国合同能源管理发展的状况,分析了我国合同能源管理发展中面临的诸多障碍。针对目前合同能源管理存在的障碍,提出了推进我国合同能源管理发展的措施和建议。     

“黑”矿山披“绿”衣,推广绿色开采技术

本论文介绍了我国的煤炭开采发展的现状,阐述了煤矿绿色开采的定义及理论基础,分析了煤矿开采产生的环境问题,提出了当前煤炭开采存在的主要可行性技术及其应用实例简析,包括:保水开采技术,固体废弃物利用技术,煤与瓦斯共采技术,减沉技术,煤炭地下气化。本论文旨在推广绿色开采技术,实现煤炭开采的可持续发展。     

基于LMDI模型的CO2排放影响因素研究——以江苏省为例

本文采用Kaya及其扩展模型将CO2排放影响因素划分为产业能源强度、生活能源强度、能源结构、产业结构、人均产出、人居收入和人口总数7个方面。根据1995～2009年江苏省一、二、三产业和居民生活部门的12种能源消费数据,利用LMDI模型分解计算出7个因素的CO2排放量和贡献值。研究结果表明,1995～2009年江苏省CO2排放量总体呈上升趋势;人均产出、人居收入和人口总数对CO2排放起到正向驱动作用,产业能源强度、生活能源强度、能源结构、产业结构起到负向驱动作用,人均产出和产业能源强度分别是影响CO2排放的正向和负向主导因素。降低CO2排放量,需要通过提高产业能源强度、调整产业结构、能源结构和促进居民生活方式和消费模式的转变,要坚持计划生育的基本国策。