Ecological footprint accounting in the life cycle assessment of products

We present and discuss ecological footprint (EF) calculations for a large number of products and services consumed in the western economy. Product-specific EFs were calculated from consistent and quality-controlled life cycle information of 2630 products and services, including energy, materials, transport, waste treatment and infrastructural processes. We formed 19 homogeneous product/process subgroups for further analysis, containing in total 1549 processes. Per group, the average contribution of two types of land occupation (direct and energy related) to the total EF was derived. It was found that the ecological footprint of the majority of products is dominated by the consumption of non-renewable energy. Notable exceptions are the EFs of biomass energy, hydro energy, paper and cardboard, and agricultural products with a relatively high contribution of direct land occupation. We also compared the ecological footprint results with the results of a commonly used life cycle impact assessment method, the Ecoindicator 99 (EI). It was found that the majority of the products have an EF/EI ratio of around 30 m²-eq. yr/ecopoint ± a factor of 5. The typical ratio reduces to 25 m² yr/ecopoints by excluding the arbitrary EF for nuclear energy demand. The relatively small variation of this ratio implies that the use of land and use of fossil fuels are important drivers of overall environmental impact. Ecological footprints may therefore serve as a screening indicator for environmental performance. However, our results also show that the usefulness of EF as a stand-alone indicator for environmental impact is limited for product life cycles with relative high mineral consumption and process-specific metal and dust emissions. For these products the EF/EI ratio can substantially deviate from the average value. Finally, we suggest that the ecological footprint product data provided in this paper can be used to improve the footprint estimates of production, import and export of products on a national scale and footprint estimates of various lifestyles.     

Evaluating the effects of embodied energy in international trade on ecological footprint in China

Based on sub-sectoral level of economy and detailed traded items, embodied energy (EE) in international trade flow in China is estimated during 1996-2004, and the effects of EE on sustainability are quantified by using one of the most popular indicators—Ecological footprint (EF). A framework of EF method, which is more relevant to realism of specific country, is proposed in this paper. The results show that China is a net importer of EE during the period covered by this study except for the year from 1997 to 1999. Imported, Exported and Net imported EE tends to increase sharply along time series. Net imported energy would increase 38% and energy consumption would increase 2.8% in 2004 if EE were taken into account. Footprint_energy is the most important part of EF components and is significantly affected by EE, and the effects of EE on EF are similar to that of Footprint_energy. Footprint_energy, EF and ecological deficit of 2004 will be underestimated about 2.92%, 1.36%, 2.83%, res pectively, if EE is not taken into the national energy budget. Continuous increase of EF and ecological deficit along time series indicates that China is moving away from sustainability. 1.47 times Chinese territories are accurately occupied by China in 1996 while 1.71 times in 2004. Obviously unsustainability procedure of China is accelerated by EE. The contribution of EE to EF and ecological deficit is small in absolute terms expressed in per capita, but the effects on whole nation are huge if the population of China multiplies them. To curb the increase of EF and ecological deficit and to achieve the goal of sustainability, some policy and measures are also proposed.     

Measuring sustainability: Why the ecological footprint is bad economics and bad environmental science

The ecological footprint is a measure of the resources necessary to produce the goods that an individual or population consumes. It is also used as a measure of sustainability, though evidence suggests that it falls short. The assumptions behind footprint calculations have been extensively criticized; I present here further evidence that it fails to satisfy simple economic principles because the basic assumptions are contradicted by both theory and historical data. Specifically, I argue that the footprint arbitrarily assumes both zero greenhouse gas emissions, which may not be ex ante optimal, and national boundaries, which makes extrapolating from the average ecological footprint problematic. The footprint also cannot take into account intensive production, and so comparisons to biocapacity are erroneous. Using only the assumptions of the footprint then, one could argue that the Earth can sustain greatly increased production, though there are important limitations that the footprint cannot address, such as land degradation. Finally, the lack of correlation between land degradation and the ecological footprint obscures the effects of a larger sustainability problem. Better measures of sustainability would address these issues directly.     

A dynamic analysis of water footprint of Jinghe River basin

Water footprint in a region is defined as the volume of water needed for the production of goods and services consumed by the local people, Ecosystem services are a kind of important services, so ecological water use is one necessary component in water footprint. Water footprint is divided into green water footprint and blue water footprint but the former one is often ignored.In this paper waterJootprint includes blue water needed by agricultural irrigation, industrial and domestic water demand, and green water needed by crops, economic forests, livestock prochtcts, forestlalands and grasslands. The study calculates the footprint of the Jinghe River basin in 1990, 1995, 2000 and 2005 with quarto methods. Results of research show that water footprints reached 164.1 ×10^8m3, 175. 69 ×10^8m3 and 178. 45 ×10^8m3 respectively in 1990, 1995 and 2000 including that of ecological water use, but reached 77.68×10^8m3, 94.24×10^8m3, 92.92×10^8m3 and 111.36 ×10^8m3 respectively excluding that of ecological water use. Green water.footprint is much more than blue water footprint; thereby, green water plays an important role in economic development and ecological construction The dynamic change of water footprints shows that blue water use increases rapidly and that the ecological water use is occupied by economie and domestic water use. The change also shows that water use is transferred from primary industry to secondary industry In primary industry, it is transferred from crops farming to forestry, and animal agriculture. The factors impelling the change include development anticipation on econonomy; government policies, readjustment of the industrial structure, population growth, the raise of urbanization level, and structurul change of consumption, low level of waler-saving and poor ability of waste water treatment.With blue water use per unit, green water use per unit, blue water use structure and green water use structure, we analyzed the difference of the six ecologieal function districts of the Jinghe River     

Application of ecological footprint in ecological industrial systems：a study case of maize-MSG production systems

To improve the comparability of the research results of ecological industry, the ecological footprint is appliedto analyze the resource utilization and environmental pollution in various subsystems, taking maize-MSG as a case.Results show that the production process from maize to MSG is a extended process of ecological footprint, and that theecological footprint of the maize production is the biggest; the extension of ecological footprint is followed by the increaseof footprint profit, which means that the extension of production chain is an important method to improve the resourcesprofit; the systems have a big proportion of the indirect energy ecological footprint; the air and water pollution in MSGsubsystem is the most serious. At last, it can be identified that ecological footprint is a good method to measure resourceutilization and environmental pollution in various subsystems of an integrated ecological industry.     

Sustainability of nations by indices: Comparative study between environmental sustainability index, ecological footprint and the emergy performance indices

The present work makes a comparison between the two most used environmental sustainability indices of nations: “ecological footprint” and “environmental sustainability index”, with two emergy ratios (renewability and emergy sustainability index). All of them are gaining space within the scientific community and government officials. Despite the efforts for obtaining an index that adequately represents the sustainability of a region, according to the result of this research, nowadays there is not yet a completely satisfactory index. We consider that all of them need to be improved, but the results point out the possibility of obtaining one better index of sustainability through the junction of ecological footprint with renewability emergy index.     

中国省级区域经济生产的资源需求——基于生态足迹模型的分析

以生态足迹模型的基本方法计算了1990年和2001年中国各省市自治区的生产足迹,以探询经济生产中产生的自然资源需求的区域差异及其影响因素。研究表明,受经济发展水平、资源人口分布、区域政策等影响,北部、西部牧业区和城市地区普遍有较大的资源需求,而南方省份的资源需求更以更快的速度在增长。     

Incorporating methane into ecological footprint analysis: A case study of Ireland

Carbon dioxide (CO₂) accounting is important to global ecological footprint analysis. However methane (CH₄), with a global warming potential (GWP) 25 times that of CO₂, should not be neglected as an environmental indicator for informed environmental management. While this is a significant component, the CH₄ associated with imported embodied energy should also be included in national greenhouse gas (GHG) inventories. This study proposes an initial method for incorporating methane into ecological footprint analyses and hopes to inform future debate on its inclusion. In order to account for differences in methane intensities from exporting countries, methane intensities for OECD countries were calculated using emission and energy consumption estimates taken directly from National Inventory Reports (NIR), published in conjunction with the Intergovernmental Panel on Climate Change (IPCC). For other countries the methane intensities were estimated using energy balances published by the International Energy Association (IEA) and IPCC default emission factors. In order to estimate embodied organic methane, material imports and exports were translated into units (such as live animals) capable of conversion into methane emissions. A significant increase in Ireland's footprint results from the inclusion of the GWP of methane is included within the footprint calculation.     

基于“低碳经济”理念和方法的生态旅游足迹评价研究——以攀枝花市为例

旅游生态足迹作为定量测度区域人类旅游活动对生态系统的压力和影响程度的评价方法,对实现区域旅游可持续发展具有积极意义。低碳经济是以低消耗、低污染、低排放为基础的经济模式。文章将"低碳经济"新的理念、方法用于旅游生态足迹定量评价,以资源性城市——攀枝花市为例,选取2005年和2008年两个旅游业发展的重要转折时间点为研究对象,计算并分析了其旅游生态足迹。结果发现,运用低碳经济理念和方法能够有效分析和解释生态足迹评价结果,监测和控制区域经济社会发展的可持续发展状况。     

Quantitative evaluation of sustainable development based on ecological footprint method: a case study of Tianjin

Since the concept of sustainable development emerged in the late 1980s, more and more countries and regions have been utilizing sustainable development as their developing strategy. But decades have passed without any effective methods available to quantitatively assess sustainable development, Since the ecological footprint evaluation method initiated in 1992, it has become popular in quantitative assessment of sustainable development because of its convenience, easy-understanding, and reliability. As one of the biggest coastal cities in north China and the economic center of the Bohai Coastal Region, Tianjin's gross domestic product (GDP) was 369.762 billion yuan in 2005, accounting for 2.0% of the whole nation's GDP The paper analyzes Tianjin's development with the ecological footprint method, and the results show that Tianjin's ecological footprint and biocapacity in 2005 were 2. 507gha/cap and 0.276gha/cap respectively. The ecological deficit was 2.230gha/cap. And from 1980 to 2005, Tianjin's ecological deficit per 104 yuan GDP decreased; while per capita ecological deficit has been tending to increase rapidly in recent years. All these results demonstrate that Tianjin is in a state of unsustainable development.     

Ecological footprint of food consumption in China：1982-2004

This paper calculates the land （including water area） requirement for food consumption in both balanced andactual diet in China by ecological footprint analysis. To determine whether logical and actual food demands are withinnatural regenerative ability, carrying capacity （excluding forestry production） is also calculated. Results show that actualdiet patterns were ecologically friendly in the period of 1982-2004 in China, mainly because of the rural moderate dietpatterns. But actual per capita footprint already overran its corresponding logic value of 0.976ha in urban areas in 2002.Productive areas for food production can satisfy the land requirement for actual diet patterns during the researchingperiod in China, nevertheless cannot satisfy that for balanced diet pattern or solve the problem of unbalanced ecologicalfootprint. The continual rising ecological footprint of food consumption in both rural and urban areas indicates that percapita footprint will keep on increasing in China and even may be more than the suggested logic value if no relevantcountermeasures are made to regulate diet patterns. Strictly speaking, China is facing food shortage, both in quality andin quantity.     

Ecological footprint of Gansu Province, China between 1997 and 2002： changes and inducement

The calculation of Ecological Footprint （EF） on the basis of Input-Output model （I-O model） was advanced by Bicknell, and modified and improved hy Ferng who corrected the footprint＇s aggregation to each sectors. For the lack of sufficient teehnique to deal with the trade between the research areas and the rest of the world, it it necessary to improve this method. And a dynamic analysis of the change of footprint based on I-O model, which could explore the factor impacting the footprint using the ,special advantage of I-O model, ought to be put into practice. After introducing the new method in detail, we calculate and compare the EF and the change of Gansu Province in the northwest of China in 1997 and 2002. The result shows that there was an increase of EF in 2002 caused by final domestic demand. Further; the inerement in EF export was 2.0 × 10^5 ha and 1.6 × 10^6 ha in import. The out-of- region support dropped from 22.6% to 18. 6%. We introduce three factors causing the EF change based on the character of I-O model： the productivity of the resourve which is explained by the change of resource used to obtain one unit output in a sector, the improvement of the economics and the final demand. Finally, we find that the effects of the three factors on the EF change are not identical except the industry sectors and the change of factors in the agriculture and the industry sectors works notably.     

Measuring sustainability: Why the ecological footprint is bad economics and bad environmental science

The ecological footprint is a measure of the resources necessary to produce the goods that an individual or population consumes. It is also used as a measure of sustainability, though evidence suggests that it falls short. The assumptions behind footprint calculations have been extensively criticized; I present here further evidence that it fails to satisfy simple economic principles because the basic assumptions are contradicted by both theory and historical data. Specifically, I argue that the footprint arbitrarily assumes both zero greenhouse gas emissions, which may not be ex ante optimal, and national boundaries, which makes extrapolating from the average ecological footprint problematic. The footprint also cannot take into account intensive production, and so comparisons to biocapacity are erroneous. Using only the assumptions of the footprint then, one could argue that the Earth can sustain greatly increased production, though there are important limitations that the footprint cannot address, such as land degradation. Finally, the lack of correlation between land degradation and the ecological footprint obscures the effects of a larger sustainability problem. Better measures of sustainability would address these issues directly.     

The water footprint of energy from biomass: A quantitative assessment and consequences of an increasing share of bio-energy in energy supply

This paper assesses the water footprint (WF) of different primary energy carriers derived from biomass expressed as the amount of water consumed to produce a unit of energy (m³/GJ). The paper observes large differences among the WFs for specific types of primary bio-energy carriers. The WF depends on crop type, agricultural production system and climate. The WF of average bio-energy carriers grown in the Netherlands is 24 m³/GJ, in the US 58 m³/GJ, in Brazil 61 m³/GJ, and in Zimbabwe 143 m³/GJ. The WF of bio-energy is much larger than the WF of fossil energy. For the fossil energy carriers, the WF increases in the following order: uranium (0.1 m³/GJ), natural gas (0.1 m³/GJ), coal (0.2 m³/GJ), and finally crude oil (1.1 m³/GJ). Renewable energy carriers show large differences in their WF. The WF for wind energy is negligible, for solar thermal energy 0.3 m³/GJ, but for hydropower 22 m³/GJ. Based on the average per capita energy use in western societies (100 GJ/capita/year), a mix from coal, crude oil, natural gas and uranium requires about 35 m³/capita/year. If the same amount of energy is generated through the growth of biomass in a high productive agricultural system, as applied in the Netherlands, the WF is 2420 m³. The WF of biomass is 70 to 400 times larger than the WF of the other primary energy carriers (excluding hydropower). The trend towards larger energy use in combination with an increasing contribution of energy from biomass will enlarge the need for fresh water. This causes competition with other claims, such as water for food.     

基于生态足迹的湖南省生态消费水平可持续性评价

可持续性测度的核心是确定人类是否生存于生态系统的承载力范围之内,而生态可持续性评价则是区域可持续发展能力的基准尺度。加拿大生态经济学家Wackernagel和Rees提出并发展的生态足迹方法,就是一种定量测量人类对自然利用程度的新方法。它将人类的消费行为与生态承载力联系起来,评价消费行为的可持续性,以此来判定区域的发展是否处于生态承载能力的范围内。文章通过借鉴这一方法,评估了湖南省2004年的生态承载力和生态消费水平,由此进行区域生态可持续性评价。评价结果表明:湖南省人均生态赤字1.2082hm2,即区域生态消费水平处于不持续状态。在此基础上,提出了促进和改善区域生态可持续性的建议。     

基于生态足迹理论的天津市可持续发展动态研究

利用生态足迹分析方法对天津市1989—2008年的生态足迹进行了计算和分析。计算结果表明：天津市人均生态足迹由1989年的1.64 hm2上升到2008年的1.65 hm2;同期的人均生态承载力则由0.27 hm2逐年上升到0.32 hm2;人均生态赤字由1.36 hm2降到1.32 hm2。虽然天津市人口对自然资源的利用呈下降趋势、生态足迹与生态承载力之间的矛盾有所减缓,但生态足迹目前仍然超出了自然生态系统的生态承载力范围,现有的发展模式是不可持续的,生态环境处于较不安全的状态。     

中国1961-2001年人地协调度演变分析--基于生态足迹模型的研究

运用生态足迹模型及已有的相关研究成果,对中国1961—2001年生态足迹和生态承载力进行计算。计算结果显示,随着人口与消费水平的上升,生态赤字在1980年代以来开始出现并持续增长,由此带来的人地不协调性的加强不仅危害着中国生态系统的稳定,也对经济的持续发展形成巨大威胁。不可持续的生产和消费方式的转变已经成为必然。     

基于县域生态足迹的乌江流域可持续发展能力研究——以重庆武隆县为例

文章运用生态足迹的理论和方法,分析了重庆武隆县2007年的生态足迹,并对该地区生态系统可持续性进行了计算分析。计算的结果显示:生态赤字为0.443909494hm2/人,生态系统的前景不容乐观,人类活动的负荷超过了该地区的生态容量。文章详细分析了导致这一状况的原因,并提出了相应的建议。     

预测生态足迹评估可持续发展

利用经验模态分解(EMD)方法分解并提取1961～2001年中国人均生态足迹与生物承载力变化的波动周期,建立具有周期性波动的非线性动力学预测模型,预测未来20年中国人均生态足迹和承载力变化,评估中国未来可持续发展进程中面临的挑战。结果表明:(1)40年来,中国人均生态足迹在波动中不断增加,具有明显的3.5年和8年2个波动周期;中国人均生物承载力在波动中不断减少,具有明显的2.7年、28年和40年3个波动周期。(2)若一切照旧,即未来20年中国人均足迹与承载力保持过去40年的年均变化率不变,则生态足迹会持续上升,2015年将达到1.710gha/cap,2025年达到2.034gha/cap;人均生物承载力持续下降,2015年将达到0.851gha/cap、2025年降到0.806gha/cap;而人均生态赤字进一步拉大,2015年0.859gha/cap、2025年1.228gha/cap,可持续发展形势比较严峻。     

The external water footprint of the Netherlands: Geographically-explicit quantification and impact assessment

This study quantifies the external water footprint of the Netherlands by partner country and import product and assesses the impact of this footprint by contrasting the geographically-explicit water footprint with water scarcity in the different parts of the world. The total water footprint of the Netherlands is estimated to be about 2300 m³/year/cap, of which 67% relates to the consumption of agricultural goods, 31% to the consumption of industrial goods, and 2% to domestic water use. The Dutch water footprint related to the consumption of agricultural goods, is composed as follows: 46% related to livestock products; 17% oil crops and oil from oil crops; 12% coffee, tea, cocoa and tobacco; 8% cereals and beer; 6% cotton products; 5% fruits; and 6% other agricultural products. About 11% of the water footprint of the Netherlands is internal and 89% is external. Only 44% of virtual-water import relates to products consumed in the Netherlands, thus constituting the external water footprint. For agricultural products this is 40% and for industrial products this is 60%. The remaining 56% of the virtual-water import to the Netherlands is re-exported. The impact of the external water footprint of Dutch consumers is highest in countries that experience serious water scarcity. Based on indicators for water scarcity the following eight countries have been identified as most seriously affected: China; India; Spain; Turkey; Pakistan; Sudan; South Africa; and Mexico. This study shows that Dutch consumption implies the use of water resources throughout the world, with significant impacts in water-scarce regions.