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1.
Estimating the material flows of rare earth elements (REEs) is essential to understanding which industries are most vulnerable to potential REE supply disruptions which, in turn, may inform policy recommendations aimed at reducing the supply risk. However, the REEs are a group of mineral commodities characterized by highly uncertain estimates of supply and demand due to the REE market's complexity, opacity, and small size. In this study, a streamlined methodology was applied to map mineral commodity first-use to final-use applications and to estimate total requirements at the national level based on available industrial data for final-use finished goods. This analysis examines REEs both as a group and individually, showing that total US requirements are between 15% and 16.5% of world requirements for the year 2015, the latest year with the most complete information available. The findings shed light on US industrial capabilities by revealing the discrepancy between the types of REEs that go into US raw material consumption and those that are contained in embedded consumption. For instance, given the United States’ large oil refining industry, US raw material consumption of lanthanum is quite high. In contrast, US raw material consumption of neodymium is relatively low, whereas embedded demand is comparatively high. This reflects the lack of industrial capacity to process REE concentrates into magnet material combined with the US's high imports of products that contain rare earth permanent magnets.  相似文献   

2.
This article presents an assessment of energy inputs of the European Union (the 15 countries before the 2004 enlargement, abbreviated EU‐15) for the period 1970–2001 and the United States for 1980–2000. The data are based on an energy flow analysis (EFA) that evaluates socioeconomic energy flows in a way that is conceptually consistent with current materials flow analysis (MFA) methods. EFA allows assessment of the total amount of energy required by a national economy; it yields measures of the size of economic systems in biophysical units. In contrast to conventional energy balances, which only include technically used energy, EFA also accounts for socioeconomic inputs of biomass; that is, it also considers food, feed, wood and other materials of biological origin. The energy flow accounts presented in this article do not include embodied energy. Energy flow analyses are relevant for comparisons across modes of subsistence (e.g., agrarian and industrial society) and also to detect interrelations between energy utilization and land use. In the EU‐15, domestic energy consumption (DEC = apparent consumption = domestic extraction plus import minus export) grew from 60 exajoules per year (1 EJ = 1018 J) in 1970 to 79 EJ/yr in 2001, thus exceeding its territory's net primary production (NPP, a measure of the energy throughput of ecosystems). In the United States, DEC increased from 102 EJ/yr in 1980 to 125 EJ/yr in 2000 and was thus slightly smaller than its NPP. Taken together, the EU‐15 and the United States accounted for about 38% of global technical energy use, 31% of humanity's energetic metabolism, but only 10% of global terrestrial NPP and 11% of world population in the early 1990s. Per capita DEC of the United States is more than twice that of the EU‐15. Calculated according to EFA methods, energy input in the EU and the United States was between one‐fifth and one‐third above the corresponding value reported in conventional energy balances. The article discusses implications of these results for sustainability, as well as future research needs.  相似文献   

3.
To analyze and promote resource efficiency in urban areas, it is important to characterize urban metabolism and particularly, material flows. Material flow analysis (MFA) offers a means to capture the dynamism of cities and their activities. Urban‐scale MFAs have been conducted in many cities, usually employing variants of the Eurostat methodology. However, current methodologies generally reduce the study area into a “black box,” masking details of the complex processes within the city's metabolism. Therefore, besides the aggregated stocks and flows of materials, the movement of materials—often embedded in goods or commodities—should also be highlighted. Understanding the movement and dispersion of goods and commodities can allow for more detailed analysis of material flows. We highlight the potential benefits of using high‐resolution urban commodity flows in the context of understanding material resource use and opportunities for conservation. Through the use of geographic information systems and visualizations, we analyze two spatially explicit datasets: (1) commodity flow data in the United States, and (2) Global Positioning System‐based commercial vehicle (truck) driver activity data in Singapore. In the age of “big data,” we bring advancements in freight data collection to the field of urban metabolism, uncovering the secondary sourcing of materials that would otherwise have been masked in typical MFA studies. This brings us closer to a consumption‐based, finer‐resolution approach to MFA, which more effectively captures human activities and its impact on urban environments.  相似文献   

4.
This article analyzes the mass of the materials that flowed through the Italian economy during 1994 and compares the results with a similar analysis of Germany, Japan, the Netherlands, and the United States published by a collaboration headed by the World Resources Institute. In order to perform this comparison, we have evaluated the mass of the materials produced within the country and the mass of the imported materials and commodities. For the domestic production, imports and exports, we have also evaluated the mass of the materials that accompany—as "hidden flows"—each physical flow.
Our analysis indicates that, in 1994, Italy experienced total material requirements (TMR) of 1,609 million metric tons (Mt), of which 727 Mt was used as direct material input (DMI). A comparison with other developed countries shows that the TMR and DMI flows, measured in mass per person and in mass per GDP unit, are, in Italy, lower than the corresponding figures evaluated for the United States, Germany, and the Netherlands. An interpretation of these results is presented. The analysis may give information useful for environmental considerations, although the limits of such an approach are made clear.  相似文献   

5.
This article presents the results of a life-cycle materials and energy flow analysis for the pulp and paper cycle in the United Kingdom. Material flows are reconstructed for the period be-tween 1987 and 1996 for all major processes associated with the paper cycle, and system energy requirements are calculated over this period using the best available data. Attention is drawn to the import dependence of U.K. paper demand, and the significant energy requirements associated with upstream forestry processes. The historical trend analysis is then used to model possible future developments in materials and energy consumption until 2010 under a variety of assumptions about process technology improvements, wastepaper utilization rates, and changing demand trends. The results indicate that policy options to increase recycling yield some energy benefits, but these are small by comparison with the benefits to be gained by reducing consumption of paper and improving process technology. The structure of the electricity supply industry in the United Kingdom means that global energy benefits could also be achieved by increasing the contribution from imported pulp.  相似文献   

6.
International trade transfers social and environmental impacts across national borders. The consumption of forest products often takes place far away from industrial production sites, and mills procure raw material from remote forests. Finland produces about 10% of forest products that are traded internationally, with the majority of its exports destined for other European countries. Here we report and analyze data that demonstrate that international leakage, in relative terms, increased faster than the production of commodities. The international consumption of products made in Finland increased, and an increase in wood imports from Russia provided the raw material for most of the incremental production. The international consumption‐production system translated the increasing global demand for Finnish products into increased harvests in Russia, until the Russian customs duties started to increase in 2007. We argue that national and regional policies for the promotion of sustainable consumption and production must be analyzed and assessed from an international, holistic perspective.  相似文献   

7.
Modeling pathways toward sustainable production and consumption requires improved spatio-temporal and material coverage of end-use product stocks. Momentarily, studies on inflow-driven, dynamic material flow analysis (dMFA) extrapolate scarce information on material end-use shares (i.e., ratios that split economy-wide material consumption to different end-use products) for single countries and years across longer time periods and global regions. Therefore, in part 1 of this work, we reviewed five methods to derive material end-use shares which use industry shipment data in physical units and monetary input–output tables (MIOTs). Herein, we comparatively apply these methods to the United States, drawing on detailed national data, as well as the multi-regional input–output model EXIOBASE3. To better match MIOT and dMFA system definitions, we propose the end-use transfer method, which re-routes specific intermediate outputs to final demand in MIOTs. In closing, we conclude on 12 points for improved end-use shares. We find mixed results regarding the fit between end-use shares derived from industry shipments and MIOTs: for detailed national data, we find good fit for some materials (e.g., aluminum), while others deviate strongly (e.g., steel). In many cases, the temporal trend of MIOT-derived end-use shares roughly agrees with industry shipments. For EXIOBASE3, we find good fit for some countries and materials, but substantial mismatches for others. Despite mixed results, combining MIOT-based end-use shares with industry shipments and auxiliary country-level data could enable improved temporal, geographical, and end-use resolution. However, the scarcity, documentation, and quality of input data are key limitations for more accurate and detailed end-use shares. This article met the requirements for a gold-gold data openness badge described at http://jie.click/badges .   相似文献   

8.
In the fifty years since Abel Wolman first published an estimate of U.S. urban metabolism, the field of urban metabolism has begun to thrive, with cities outside the United States being much of the focus. As cities attempt to meet local and international sustainability goals, it is time to revisit the metabolism of cities within the United States. Using existing empirical databases for material flows (the Freight Analysis Framework) and a published database on urban water flux, we provide a revised estimate of urban metabolism for the typical U.S. city. We estimate median values of metabolism for a city of one million people, considering water resources, food, fuel, and construction materials. Food consumption and waste production increased substantially to 3,800 metric tons per day and 4,900 metric tons per day, respectively. To facilitate a second generation of urban metabolism, we extend traditional analyses to include the embedded energy required to facilitate material consumption with important implications in determining sustainable urban metabolism. We estimate that a city of one million people requires nearly 4,000 gigajoules of primary energy per day to facilitate its metabolism. Our results show high heterogeneity of urban metabolism across the United States. As a result of the study, we conclude that there is a distinct need to promote policies at the regional or city scale that collect data for urban metabolism studies. Urban metabolism is an important educational and decision‐making tool that, with an increase in data availability, can provide important information for cities and their sustainability goals.  相似文献   

9.
The United States is not only the world's largest economy, but it is also one of the world's largest consumers of natural resources. The country, which is inhabited by some 5% of the world's population, uses roughly one‐fifth of the global primary energy supply and 15% of all extracted materials. This article explores long‐term trends and patterns of material use in the United States. Based on a material flow account (MFA) that is fully consistent with current standards of economy‐wide MFAs and covers domestic extraction, imports, and exports of materials for a 135‐year period, we investigated the evolution of the U.S. industrial metabolism. This process was characterized by an 18‐fold increase in material consumption, a multiplication of material use per capita, and a shift from renewable biomass toward mineral and fossil resources. In spite of considerable improvements in material intensity, no dematerialization has happened so far; in contrast to other high‐income countries, material use has not stabilized since the 1970s, but has continued to grow. This article compares patterns and trends of material use in the United States with those in Japan and the United Kingdom and discusses the factors underlying the disproportionately high level of U.S. per capita resource consumption.  相似文献   

10.
Despite accounting for almost 50% of global material use, nonmetallic minerals—mostly used for construction of buildings and infrastructure—are the material flow analysis (MFA) category with the highest uncertainty. The main reason for this is incomplete reporting in official national statistics because of ease of availability and the low per‐unit cost of these materials. However, the environmental burden associated with nonmetallic minerals, which include energy use for extraction and transport, land‐use change, and disposal of large amounts of construction demolition waste, call for a thorough understanding of the magnitude of nonmetallic mineral flows. Previous estimates for nonmetallic minerals have used simplistic assumptions. This study aims to increase the precision of nonmetallic mineral accounts at national and global level using consumption of bitumen, bricks, cement, and railways in combination with technical coefficients from the engineering literature to infer the actual yearly consumption of nonmetallic minerals. We estimate the extraction of nonmetallic minerals and provide uncertainty estimates for the new accounts as well as information about consumption by different sectors. Analyzing the evolution of consumption for seven world regions, we find that, in North America and Europe, the consumption of nonmetallic minerals over the past 40 years has followed the growth patterns of population, whereas for all other regions consumption has been closely related to gross domestic product (GDP). A more accurate account of global and country‐by‐country extraction of nonmetallic minerals may provide insights into supply shortages and inform waste management strategies for construction and demolition waste.  相似文献   

11.
Large-scale milk production and consumption historically have been localized to Europe and countries with large European-derived populations. However, global patterns have now shifted, with dramatic increases in milk consumption in Asian countries and flat or declining consumption in European and European-derived countries. Efforts to market it around the world emphasize milk's positive effects on child growth, and, by extension, the individual and national benefits that derive from that growth. At the same time, milk has newly emerged in milk promotions in the United States as food that facilitates weight loss. Milk has been able to achieve a global presence and continuing relevance in populations in which its consumption has been declining by continually transforming and repositioning itself as a "special" food with properties able to alleviate the health concerns seen as most salient at the time.  相似文献   

12.

Purpose

The concept of electro mobility is gaining importance and has become more dynamic in recent years, particularly in developed economies. Besides a significant reduction of mobility-related CO2 emissions, electro mobility is also expected to minimize the current dependence on oil, while maximizing energy conversion efficiency. However, the associated shift in resource requirements towards so-called strategic metals gives reason to suspect that trade-offs could threaten the desired merits of e-mobility with regard to sustainability. This study aims to give a more comprehensive understanding of the challenges—including the issue of uncertainties—which the broad implementation of e-mobility could place on resource availability and especially on a sustainable management of special metals for the high voltage traction batteries forming the heart of the electric powertrain.

Methods

Future metal flows for three possible cathode materials containing the special metals lithium and cobalt are estimated in this paper by means of a Material Flow Analysis. Using two scenarios (dominant and pluralistic) projecting the annual demand for electric vehicles until 2050 and the free software STAN in order to perform the calculation steps to build up the model for the analysis, the MFA considers the resource input requirements based on annual vehicle registrations and the consequent energy requirements.

Results and discussion

The results indicate continuously rising lithium requirements with a wide variation in absolute terms depending on the scenario, which can be considered symptomatic for the uncertainty regarding the development of e-mobility. In the case of cobalt, the projected demand trajectories differ even more drastically between the two scenarios. In comparison to lithium though, for both scenarios cobalt requirements in absolute terms are much less than lithium requirements. With a view to currently known reserves, the cumulative demand for battery technology projected in the dominant scenario will consume 74–248 % (for two different cases) of the lithium reserves and 50 % of the cobalt reserves by 2050.

Conclusions

Despite significant differences between the examined scenarios, it becomes clear that e-mobility will be an increased driver for cobalt and particularly lithium demand in the future. Exact increases in demand for both metals are difficult to predict, especially due to the necessity of numerous assumptions, such as recycling rates, as well as data availability and quality. The results of this study imply a shift from managing primary resources, resource uses, and waste separately, towards managing materials, i.e., resource flows and their implications over the entire life cycle.
  相似文献   

13.
The benefits of using lactic acid bacteria in the food chain, both through direct consumption and production of ingredients, are increasingly recognised by the food industry and consumers alike. The regulatory environment surrounding these products is diverse, covering foods and food ingredients, processing aids, feed additives and dietary supplements. On a global basis, there are different approaches taken by the various regulatory authorities. While in Europe, the national legislation is gradually being harmonised, predominantly through the Novel Foods Regulation, there is still a wide disparity between the stringency of regulation of microbial products fed to animals and the comparatively relaxed approach to non-novel microbial products intended for human consumption. In the United States, the onus is on self-regulation of the manufacturer, with the Generally Recognised As Safe (GRAS) and Dietary Supplement Health Education Act (DSHEA) notification schemes encouraging industry to be more open about the ingredients they market. In Japan, the Foods for Special Health Use system continues to gain recognition as more products are approved, and is a potential model for other countries in regulating functional foods. Despite the different approaches to regulating these products, safety of microorganisms such as lactic acid bacteria in the food chain is paramount in all countries. This paper discusses the regulatory requirements of microbial products, predominantly lactic acid bacteria within the global markets, focusing mainly on the developments in Europe.  相似文献   

14.
Anoplophora glabripennis Motschulsky, an Asian cerambicid beetle, was first found in the United States in 1996 and was likely introduced into the United States through infested wood packing materials and dunnage. Methyl bromide (MeBr) fumigation is an internationally accepted treatment for such wood-boring beetles, but the use of MeBr is scheduled for reduction or elimination as alternatives become available. The use of MeBr can be reduced by more efficient and technically sound fumigation techniques, including good circulation and proper loading. Concentration x time products (CxT) reported for A. glabripennis in solid wood timbers were used to test estimated doses in container fumigations conducted in Tianjin and Shanghai, China, during years 2002-2003. We found that CxT products observed were generally adequate and would support reduced doses of MeBr at temperatures intermediate (10.0 and 15.6 degrees C) to the Animal and Plant Health Inspection Service schedule of 80 g and 48 g/m3 at > or =4.4 and > or = 21.1degrees C, respectively. The use of fans is recommended, and loading of the containers should never reach 100% to allow for better circulation and desorption. Proper use of fans will allow for better aeration and increase safety to inspectors and consignees of containerized fumigated commodities.  相似文献   

15.
The rapid technological evolution and adoption of consumer electronics highlights a growing need for adaptive methodologies to evaluate material consumption at the intersection of technological change and increasing consumption. While dematerialization and the circular economy (CE) have both been proposed to mitigate increasing material consumption, recent research has shown that these methods may be ineffective at achieving net material use reduction: When focused on specific products, these methods neglect the effects of complex interactions among and increasing consumption of consumer electronic products. The research presented here develops and applies a material flow analysis aimed at evaluating an entire “product ecosystem,” thereby including the effects of increasing consumption, product trade‐offs, and technological innovations. Results are then used to evaluate the potential efficacy of “natural” dematerialization (occurring as technology advances or smaller products substitute for larger ones) and CE (closing the loop between secondary material supply and primary material demand). Results show that material consumption by the ecosystem of electronics commonly used by U.S. households peaked in 2000. This consumption relies on increasingly diverse materials, including gold, cobalt, and indium, for whom secondary supply is still negligible, particularly given low recovery rates, often less than 1%. Potential circularity metrics of material “dilution,” “dispersion,” and “demand mismatch” are also evaluated, and indicate that CE approaches aimed at closing the loop on consumer electronic material still face several critical barriers particularly related to design and efficient recycling infrastructure.  相似文献   

16.
Carbon (C) emission and uptake due to land use and land cover change (LULCC) are the most uncertain term in the global carbon budget primarily due to limited LULCC data and inadequate model capability (e.g., underrepresented agricultural managements). We take the commonly used FAOSTAT‐based global Land Use Harmonization data (LUH2) and a new high‐resolution multisource harmonized national LULCC database (YLmap) to drive a land ecosystem model (DLEM) in the conterminous United States. We found that recent cropland abandonment and forest recovery may have been overestimated in the LUH2 data derived from national statistics, causing previously reported C emissions from land use have been underestimated due to the definition of cropland and aggregated LULCC signals at coarse resolution. This overestimation leads to a strong C sink (30.3 ± 2.5 Tg C/year) in model simulations driven by LUH2 in the United States during the 1980–2016 period, while we find a moderate C source (13.6 ± 3.5 Tg C/year) when using YLmap. This divergence implies that previous C budget analyses based on the global LUH2 dataset have underestimated C emission in the United States owing to the delineation of suitable cropland and aggregated land conversion signals at coarse resolution which YLmap overcomes. Thus, to obtain more accurate quantification of LULCC‐induced C emission and better serve global C budget accounting, it is urgently needed to develop fine‐scale country‐specific LULCC data to characterize the details of land conversion.  相似文献   

17.
Shaping sustainable, equitable African cities requires strengthened investigations into the cities’ current resource flows, infrastructure systems, and future resource requirements. The field of urban metabolism (UM) offers multiple forms of analysis with which to map, analyse, and visualize urban resource profiles. Challenges in assessing UM in African cities include data scarcity at the city level, difficulty in tracking informal flows, lack of standardized methods, and the open nature of cities. However, such analyses are needed at the local level, given that city practitioners cannot rely purely on urban planning traditions of the global North or the typically broad studies about urban Africa, for supporting strategies toward sustainable urban development. This article aims to draw together the concepts of sustainable development and UM and explore their application in the African context. Further, the article estimated resource profiles for 120 African cities, including consumption of biomass, fossil fuels, electricity, construction materials, and water, as well as emissions of carbon dioxide. These resource profiles serve as a baseline from which to begin assessing the current and future resource intensity of these cities. It also provides insights into the cities’ relative resource impact, future consumption trends, and potential options for sustainability interventions.  相似文献   

18.
National material stock (MS) accounts have been a neglected field of analysis in industrial ecology, possibly because of the difficulty in establishing such accounts. In this research, we propose a novel method to model national MS based on historical material flow data. This enables us to avoid the laborious data work involved with bottom‐up accounts for stocks and to arrive at plausible levels of stock accumulation for nations. We apply the method for the United States and Japan to establish a proof of concept for two very different cases of industrial development. Looking at a period of 75 years (1930–2005), we find that per capita MS has been much higher in the United States for the entire period, but that Japan has experienced much higher growth rates throughout, in line with Japan's late industrial development. By 2005, however, both Japan and the United States arrive at a very similar level of national MS of 310 to 375 tonnes per capita, respectively. This research provides new insight into the relationship between MS and flows in national economies and enables us to extend the debate about material efficiency from a narrow perspective of throughput to a broader perspective of stocks.  相似文献   

19.
In this study we use economic input-output analysis to calculate the inequality footprint of nations. An inequality footprint shows the link that each country''s domestic economic activity has to income distribution elsewhere in the world. To this end we use employment and household income accounts for 187 countries and an historical time series dating back to 1990. Our results show that in 2010, most developed countries had an inequality footprint that was higher than their within-country inequality, meaning that in order to support domestic lifestyles, these countries source imports from more unequal economies. Amongst exceptions are the United States and United Kingdom, which placed them on a par with many developing countries. Russia has a high within-country inequality nevertheless it has the lowest inequality footprint in the world, which is because of its trade connections with the Commonwealth of Independent States and Europe. Our findings show that the commodities that are inequality-intensive, such as electronic components, chemicals, fertilizers, minerals, and agricultural products often originate in developing countries characterized by high levels of inequality. Consumption of these commodities may implicate within-country inequality in both developing and developed countries.  相似文献   

20.
This article analyzes the policy choices and programmatic elements of extended producer responsibility (EPR) as implemented in the United States and Canada. The article traces the historical development of EPR in each country and defines common features of EPR in each nation. The U.S. states and the Canadian provinces have assumed the primary role, rather than the federal governments, for enacting producer responsibility requirements in their respective countries. However, the paths taken demonstrate several fundamental differences, including the prevalence of individual versus collective responsibility and the financing mechanisms implemented for EPR. Given the deepening experience with EPR and the breadth of its application to a widening array of products in the United States, the Canadian model for EPR is starting to receive more examination from policy makers in the United States, indicating that the policy and programmatic differences between the two nations may eventually be narrowing. The comparative policy analysis is illustrated through the lens of EPR regulatory efforts for waste electronics, with particular profiles of the programs in the State of Minnesota and Province of Ontario. Both approaches broadly reflect many of the policy considerations and governance and programmatic themes that dominate EPR programs in each country. Finally, the article offers recommendations for collaborative work between the United States and Canada to explore consistency between programs and other complementary strategies to support producer responsibility activities.  相似文献   

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