The Metabolic Transition in Japan

Abstract

The notion of a (socio-) metabolic transition has been used to describe fundamental changes in socioeconomic energy and material use during industrialization. During the last century, Japan developed from a largely agrarian economy to one of the world's leading industrial nations. It is one of the few industrial countries that has experienced prolonged dematerialization and recently has adopted a rigorous resource policy. This article investigates changes in Japan's metabolism during industrialization on the basis of a material flow account for the period from 1878 to 2005. It presents annual data for material extraction, trade, and domestic consumption by major material group and explores the relations among population growth, economic development, and material (and energy) use. During the observed period, the size of Japan's metabolism grew by a factor of 40, and the share of mineral and fossil materials in domestic material consumption (DMC) grew to more than 90%. Much of the growth in the Japanese metabolism was based on imported materials and occurred in only 20 years after World War II (WWII), when Japan rapidly built up large stocks of built infrastructure, developed heavy industry, and adopted patterns of mass production and consumption. The surge in material use came to an abrupt halt with the first oil crisis, however. Material use stabilized, and the economy eventually began to dematerialize. Although gross domestic product (GDP) grew much faster than material use, improvements in material intensity are a relatively recent phenomenon. Japan emerges as a role model for the metabolic transition but is also exceptional in many ways. The notion of (socio-) metabolic transition has been introduced to describe fundamental changes in socioeconomic energy and material use during industrialization (Fischer-Kowalski and Haberl 2007; Haberl et al. 2011). It has been argued that the transition from an agrarian to an industrial society typically implies a multiplication of both metabolic rates (material and energy flows per capita and year) and population and, consequently, also metabolic scale (the overall size of extraction and trade flows). Not only the size of material and energy flows but also the composition of these flows changes, and a shift from biomass toward mineral and fossil materials occurs (Krausmann et al. 2008b). Researchers have also shown that growth in material use typically is accompanied by a considerable decline in resource intensity (resource use per unit of gross domestic product [GDP]; Krausmann et al. 2009). Research so far has focused on the energy side of the metabolic transition (Gales et al. 2007; Krausmann et al. 2008c; Warr et al. 2010), and only limited empirical evidence from material flow accounting (MFA) exists. Most MFA studies are limited to a few decades, and, at best, time series begin in the 1970s (e.g., Russi et al. 2008; Schandl and West 2010). These data sets allow for the analysis of a specific phase of industrialization that was marked by the oil price shocks of the 1970s and the subsequent deceleration of growth in energy and material use in most countries (Bringezu et al. 2004; Krausmann et al. 2008c). These studies thus miss important phases of industrial development and the metabolic transition, such as the decades after World War II (WWII) and the emergence of a society of mass production and mass consumption, during which tremendous increases in per capita resource use in industrial countries occurred (cf. Grübler 1998; Steffen et al. 2007). We know of only two comprehensive long-term material flow data sets consistent with current conceptual and methodological standards in MFA: Schandl and Schulz (2002) analyzed material use in the United Kingdom for the period from 1850 to 1998, and Krausmann and colleagues (2009) recently published a global time series of material extraction for the last century.1 Long-term data have also been published for selected material flows—for example, for the United States (Rogich and Matos 2002). This article presents a time series of material flow data for the Japanese economy for the period from 1878 to 2005.2 With this study, we significantly extend the period for which material flows in the Japanese economy have been compiled so far: A first material flow account for Japan, covering the period from 1975 to 1993, has been included in the seminal multinational MFA study by the World Resources Institute (Adriaanse et al. 1997), and Japan's Ministry of the Environment (e.g., Ministry of the Environment 2007) has compiled annual time series data beginning in 1980.3 The time period observed in this article begins right after the Meiji restoration and covers Japan's transformation from an agrarian country to one of the leading economies in the world, then the so-called lost decade after the Japanese economic bubble burst in the late 1980s and economic recovery in the 1990s (Allen 1981; Hentschel 1986). It also includes important incidents at the global scale, such as the world economic crisis in the 1930s, World Wars I and II, and the oil price shocks following the initial incident in 1973. After a brief description of methods and data sources, we present annual time series data for the period from 1870 to 2005 for extraction, imports, and exports of materials by main material group and aggregate material flow indicators, such as domestic material consumption and material intensity. On the basis of these data, we investigate the path of the metabolic transition in Japan. We identify changes in material input and use during Japan's industrialization and discuss the significance of socioeconomic factors underlying the observed changes in the physical economy of Japan. Finally, we explore changes in the material intensity of the Japanese economy and the issue of dematerialization. We followed the basic principles and current international standards of economy-wide MFA, as proposed, for example, by the European Statistical Office (Eurostat 2009; see also OECD 2008) to account for used extraction and direct imports and exports of materials. Unused extraction and indirect flows associated with imports and exports were not accounted for (see, e.g., Bringezu et al. 2009). We applied standard estimation procedures for the extraction of flows not reported in statistical sources and adapted them for long-term historical application. Our data are thus consistent with the current state-of-the-art methods of MFA and are comparable to other existing material flow accounts for Japan covering more recent periods (see the Data Quality and Reliability section of this article). Our database provides material flow data at a medium level of aggregation, discerning a maximum of 61 material groups. For this article, we use aggregate information and present data on the level of four main material groups: biomass, fossil energy carriers, metal ores, and nonmetallic minerals (including construction minerals). Data on fossil energy carriers, metal ores, and nonmetallic minerals are also subsumed under mineral and fossil materials (as opposed to biomass). We calculated the following material flow indicators (see Fischer-Kowalski et al. 2011): domestic extraction (DE), imports and exports, domestic material consumption (DMC, defined as DE plus imports minus exports), physical trade balance (PTB, defined as imports minus exports), trade dependency (defined as PTB per DMC), and material intensity (MI, defined as DMC per unit of GDP; MI is the inverse of material productivity). We refer to per capita values of domestic material (and energy) consumption as metabolic rates. We quantified material extraction and use for Japan proper as defined by the statistical sources we have used for the respective period. We did not include material extraction in Japanese colonies (e.g., Formosa [Taiwan], Chosen [Korea], or Manchuria), but trade between Japan proper and its colonies was, rather, accounted for as foreign trade. In practical terms, this means that the observed territorial system roughly resembles that of Japan in its current boundaries throughout the observed period.4 Our main data source was the excellent Japanese historical statistics database maintained by the Statistics Bureau Japan (2008), which provides, among other data, comprehensive physical information on agriculture, forestry, fishing, mining, the production of related industries, and trade. It contains annual time series data from as early as 1868 to the most recent years. Some of the series are shorter, however, and several cover the period after WWII only. Other important publications on Japanese historical statistics include a comprehensive data collection by the Bank of Japan (1966) and early data on foreign trade by Ishibashi (1935). Additionally, we used international data compilations and sources to complete and cross-check our data series. These data compilations include those from Mitchell (2003), FAOSTAT (2010), UN (2007), IEA (2007), USGS (2008), and United Nations Statistical Division (2008) and more specific literature. Data on population and GDP (in international Geary-Khamis Dollars) were taken from the work of Maddison (2008).5 We combined information on crop harvest and fish catch from Statistics Bureau Japan (2008) and FAOSTAT (2010). Complete and comparable data were available for the whole period. We estimated crop residues using region-specific information on corn-straw rations (harvest indexes) from the work of Krausmann and colleagues (2008a), for which we assumed changes over time (i.e., a 20% to 80% increase in harvest indexes during the last 130 years, depending on crop species). Grazed biomass was estimated on the basis of data on livestock numbers (Statistics Bureau Japan 2008; FAOSTAT 2010) and average feed intake per head and day. Feed intake data were calculated on the basis of ruminant production (milk yield per cow, average live weight) and assumptions on productivity changes. To arrive at the amount of grazed biomass and other roughage harvested to feed livestock, we subtracted information on available feed (market feed, fodder crops, and crop residues used as feed) from total demand. Data on feed supply were derived from the work of Statistics Bureau Japan (2008) and FAO (2010). For the period from 1878 to 1961, only limited information on the volume of available market feed was available, and we assumed that grazed biomass and harvest from grassland covered 70% of the feed demand of grazers. The feed balance was performed in dry matter; we converted results into MFA-relevant mass, assuming an average moisture content of 15% (Eurostat 2009). Data from Statistics Bureau Japan (2008) cover fuel wood extraction beginning in 1929 and lumber harvest beginning in 1954. This information (which includes some statistical breaks and implausibilities, most likely due to unit confusions in the sources) was completed with data from the Bank of Japan (1966) and FAOSTAT (2010) and cross-checked with information from Mitchell (2003). For the period prior to 1929, fuel wood harvest was extrapolated from the average per capita consumption of the early 1930s and population numbers. We assume that official fuel wood data underestimate actual use in early periods, particularly in the period prior to WWII, for which we arrive at a comparatively low per capita DMC of fuel wood, 0.2 tonnes per capita per year (t/cap/yr). Information on the extraction of nontimber and fuel-wood products from forests was scarce; however, the involved mass flows are typically very low. The extraction of fossil fuels is covered completely in the work of Statistics Bureau Japan (2008). Additionally, we used data from the Bank of Japan (1966), IEA (2007), and Mitchell (2003) to cross-check data and eliminate minor flaws. Data on mineral extraction provided by Statistics Bureau Japan (2008) begin in 1874; however, for many mineral materials, data series only begin in the early 20th century. To complement data for the years prior to WWII, we used data provided by the Bank of Japan (1966) and Torgasheff (1930). For the period from 1960 to the present, we also used data from USGS (2008) and the UN (2007) to cross-check and amend the database. We calculated the amount of extracted gross ores using information on metal content, ore grades, and coupled production derived from the work of USGS (2008) and Torgasheff (1930). The applied extrapolation coefficients were kept constant over time. Data on construction minerals were not reported in available statistical sources, except for some years and some specific items. In particular, flows of natural aggregates used in construction and limestone for cement production had to be estimated. We used the procedure proposed by Krausmann and colleagues (2009) (and applied in a slightly modified form by Schandl and West [2010] in a recent study on material flows in the Asia-Pacific region) and estimated the demand for sand and gravel used for concrete and asphalt production on the basis of data on cement and bitumen consumption. We assumed a ratio of sand and gravel to cement in concrete of 6.1 and of gravel to bitumen in asphalt of 20. Furthermore, we assumed that 1.15 tonnes of limestone are required to produce 1 tonne of cement (Krausmann et al. 2009). Data on cement production and consumption were derived from the work of Cembureau (1998), Statistics Bureau Japan (2008), and Bank of Japan (1966); bitumen consumption was derived from data in the work of IEA (2007) and Statistics Bureau Japan (2008). Additionally, we calculated sand and gravel demand for the construction of railroads assuming 10,000 t of sand and gravel per kilometer of newly built railroad tracks (Bank of Japan 1966; Statistics Bureau Japan 2008) to cover important construction activities in earlier periods. In general, the applied coefficients are conservative, and it can be assumed that the procedure has a tendency toward underestimating the overall amount of natural aggregate use: Our estimate emphasizes natural aggregates, which in most countries account for more than 90% of construction minerals, but we neglect other materials, such as clay for bricks. Also, filling materials are not fully accounted for (Krausmann et al. 2009). For the period from 1960−1961 to 2005, we used data from FAO (2010) for trade with agricultural and forestry products, data from IEA (2007) for trade with fossil energy carriers, and trade data from United Nations Statistical Division (2008) at the three-digit level of the Standard International Trade Classification (SITC, Revision 1; approximately 300 items) for trade with all other products. Data for the period from 1946 to 1960 were derived from Statistics Bureau Japan (2008) and are presumably incomplete (we assume that we do not account for some 20% to 40% of the total trade flows in mass in that period). Data for the period 1870–1933 are based on the work of Ishibashi (1935) and include trade with Japanese colonies. Trade between Japan proper and its colonies was significant and accounted for 23% of total imports and 26% of total exports in 1933. For the period from 1934 to 1945, no trade data were available. Although trade flows in that period might have increased, we assume that the overall mass of trade flows remained small compared to DE; after WWII, trade volumes (in monetary terms) reached the level of the mid-1930s only in the late 1950s (Allen 1981). Data on material flows were used to calculate total primary energy supply (TPES). We converted fuel wood and fossil fuel DMC into energy units using material-specific coefficients for gross calorific values. Energy flow data derived from MFA were supplemented with energy inputs from hydropower, nuclear heat, and geothermal sources. We converted data on electricity output from hydro and nuclear power plants into primary energy input by applying coefficients for average conversion efficiency (Warr et al. 2010).6 One of the reasons that most MFA studies rarely extend earlier than the 1970s is that compiling long-term time series data of sufficient robustness and comparability is a difficult and laborious process. International data compilations and digitally available data get increasingly scarce for periods prior to the 1970s. In the case of Japan, we could compile a time series covering 135 years because the country has a long tradition of statistical records and comprehensive sources for historical statistics (e.g., Statistics Bureau Japan [2008] provided a reliable empirical backbone for the material flow account). Long-term data do have their weaknesses, however, and uncertainty tends to increase the further time series are extended to historic periods, as underreporting, data gaps, and flaws become more frequent. Japan has a long tradition in statistics, and the quality of the used sources must be regarded as very high. Nevertheless, we assume that we slightly underestimate material extraction, in particular for the early years. As has been outlined in the Methods and Data section, our estimates for construction minerals and some biomass flows, in particular the extraction of wood and other forest products, have to be considered conservative. Furthermore, the data coverage is insufficient for the period from 1934 to 1945, for which only data on DE, but no trade data, were available. Also, for the years 1946 to 1960, trade data were incomplete, and net imports have to be considered to be low (roughly by 20% to 40%). Hence, aggregate indicators for this period must be interpreted cautiously. Despite these caveats, it can be assumed that our data represent the size of material flows for the four material groups and their development over time fairly well, even in the time period from 1878 to 1960. We assume that possible underestimations of some flows are not significant enough to distort the overall picture of trends in material use over time. The reliability of our data is further corroborated when compared with official Japanese MFA data: For the period from 1980 to 2004, MFA accounts published by the Japanese Ministry of the Environment (2007) are available. For most flows and material groups, our data match very well with the Japanese data set; this is in particular encouraging for domestic extraction, for which large material flows were estimated (e.g., grazed biomass, sand and gravel, and gross ores). For the extraction of gross ores (which is a very small flow compared to the other main material groups in Japan) we arrive at considerably higher figures than those reported in the official Japanese data set; however, an in-depth review showed that Japanese data most likely refer to metal content rather than gross ore. Figure 1 shows that our results are very similar to official Japanese MFA data with respect to both the overall amount of DMC and its development over time. In terms of trends over time, our data also match well with the Japan data published recently in a multinational material flow database for the Asia-Pacific covering the period from 1970 to 2005 (Schandl and West 2010). Schandl and West's data are, however, not based on national statistical sources or country-specific coefficients used in estimates, which explains differences in metabolic scale (figure 1). Comparison of aggregate domestic material consumption (DMC) from available material flow analysis (MFA) data sets for Japan for the period from 1970−1980 to 2005: The official Japanese MFA data published by the Ministry of Environment (2007), the Asia-Pacific data set of Schandl and West (2010), and this data set. Gt/yr = gigatonnes per year. Figure 2 shows the development of DE, trade flows, and DMC by the four main material groups. In 1878, biomass accounted for almost 90% of DE, but the extraction of fossil energy carriers and mineral materials increased continuously, and by 1923 it surpassed biomass in terms of mass. Between 1878 and the 1940s, total extraction multiplied almost sevenfold, from 0.03 Gigatonnes (Gt; billion tonnes) to 0.2 Gt. At the end of WWII, DE slumped to only half of the prewar value, in particular the extraction of mineral materials. After 1947 DE quickly recovered; it had already surpassed the prewar peak by 1951 and then experienced a sheer explosion in the period up until 1973. The steep increase in overall DE was caused by a surge in nonmetallic minerals, mostly natural aggregates for construction, which dwarfed all other material flows. The steep rise of nonmetallic minerals DE was interrupted by the oil price shock in 1973, but DE continued to rise, to reach its maximum in 1991. The development of the extraction of all material groups shows an inverted U shape and declines after early peaks: DE of fossil energy carriers peaked as early as 1943, not quite reaching this level again in a second peak after WWII in 1962. DE of biomass peaked in 1960, and DE of ores peaked in 1967. During the observed period, aggregate extraction grew 36-fold and reached a peak in 1991 at 1.4 Gt (i.e., 3% of global DE at that time). Biomass was the material group with the lowest growth; it quadrupled between 1878 and 1960. After 1960, DE of biomass declined from 0.13 to 0.08 Gt, or by 40%. Material flows in Japan from 1878 to 2005: (A) Domestic extraction (DE) of raw materials; (B) imports, (C) exports, and (D) domestic material consumption (DMC) of raw materials and manufactured products. Manufactured products have been allocated to one of the four main material groups on the basis of the dominating material. Note the different scales of figures 2A through 2D. Trade flows exhibit an even more extreme growth pattern (figure 2). Mass flows entering or leaving Japan through trade were very small in the decades before WWII: Total imports only reached one-tenth of DE in the 1930s, and exports never exceeded 5% of DE. The most relevant trade flows in this period were imports of biomass, above all food items and cotton, and, in later years, also of ores. On the export side, coal and, increasingly, manufactured products were the dominating mass flows. Unfortunately, no trade data for the period from 1934 to 1955 are available, although it can be assumed that imports of wood and minerals from Manchuria and other colonies were considerable. After the war, both imports and exports experienced steep growth: They grew at average annual rates of 21% and 26%, respectively, during the period from 1955 to 1971. The surge of imports was interrupted in 1973 (due to the oil price shock) but continued in the 1980s, whereas the growth of exports slumped between 1985 and 1990. By 2005, exports had reached 15% of DE and imports more than 80%. During the whole period after WWII, imports were much larger than exports, and Japan remained a massive net importer of all four material groups. The country imported large amounts of biomass and fossil energy carriers but also ores and minerals. Exports mostly consisted of products from metals and nonmetallic minerals. As a result of the development of DE and trade flows, DMC (figure 2D) grew slowly in the period before WWII, from 0.04 Gt in 1878 to 0.23 Gt in the 1940s, but surged in the 1950s and 1960s, to 1.8 Gt in 1973. The effect of the oil price shocks on DE and imports is clearly reflected in material consumption, which dropped considerably in 1973. After 1973, the previous growth dynamic came to a halt. DMC experienced major ups and downs and reached its peak at 2 Gt in 1990. Ever since, Japan's economy has been dematerializing, and DMC decreased by 15%, to 1.7 Gt in 2005. Japan presents itself as a showcase of the metabolic transition from an agrarian to an industrial metabolic regime. During the observed 130-year period, the country's population grew by a factor of four, but metabolic rates surged by more than an order of magnitude: Material use (DMC/cap/yr) grew by a factor of 14, and primary energy supply (TPES/cap/yr) grew by a factor of 50 (table 1 and figure 3). Although biomass dominated material and energy use in the late 19th century, its contribution to DMC and TPES was dwarfed to less than 10% a century later (table 2). This transition was by no means a steady process. Three periods with distinct patterns of change in material and energy use can be identified: a period of moderate physical growth from 1878 to the outbreak of WWII (interrupted by the world economic crises of the 1930s); a period of radical growth beginning shortly after WWII and lasting until the early 1970s; and, finally, a period of stagnation beginning in 1973, which was characterized by strong fluctuations and, eventually, dematerialization. Table 1 shows average annual growth rates for major physical and economic headline indicators for these three periods. Growth rates for all resource use indicators are moderate in the first phase, increase by a factor of three to five during the second phase, and are low or even negative during the third phase. Metabolic rates: (A) material use (domestic material consumption [DMC]) and total primary energy supply (TPES) per capita and year, and (B) DMC per capita by main material groups. t/cap/yr = tonnes per capita per year. In the 1880s, during the Meiji period, the metabolism of the Japanese economy resembled the metabolic profile of a typical agrarian regime (Krausmann et al. 2008b). Four-fifths of the population was making its living in agriculture (table 2); material consumption amounted to merely 1.1 t/cap/yr, and biomass accounted for almost 90% of DMC. Nearly all material resources were met from domestic extraction; imports and exports were insignificant. But the shift from an organic to a mineral economy (Wrigley 1988) was already underway. The so-called Meiji restoration at the end of the 1860s led to the abolishment of feudal traditions and institutions and opened the country to the West. Japan began to industrialize and engaged in international trade. Much of this early industrialization was in the silk and textile industry in small-scale factories and based on biomass as the primary raw material. The expansion of metal manufacturing and chemical industries in the late 1930s resulted in a more material-intensive development and an increase in the per capita consumption of mineral and fossil materials (figure 3B). In this period, the merchant fleet and the railway system were expanded, and exports in monetary terms surged (Allen 1969). Japan's (military) expansion in the Far East, which culminated in the Sino-Japanese War in 1937, significantly contributed to rapid industrialization in this period (Allen 1981). The corresponding material flows, however, remained comparatively low (figure 2). Japan was exporting considerable amounts of ores and, later, also coal and importing predominantly food and cotton. But overall, imperial Japan rather followed a policy of economic self-sufficiency and trade dependency (net imports as a share of DMC remained low, at only 8% in 1930; figure 4). In the first decades of the 20th century, heavy industry also gained significance and contributed to physical growth, but its per capita output in physical terms remained rather low.7 Industrial growth is reflected in increasing but, overall, still low values of material and energy use per capita (figure 3). But even in this period of moderate physical growth, material and energy use increased faster than population and GDP (table 1). All in all, per capita material use tripled, and the share of biomass in DMC declined to less than 50% in the years prior to Japan's involvement in WWII. Physical trade balance (PTB): (A) PTB per capita and (B) trade dependency (PTB per domestic material consumption [DMC]) by main material groups. Note that PTB is calculated as physical imports minus exports. Negative values designate net exports. Trade dependency is defined as net trade (PTB) per DMC. WWII left Japan with massive destruction. Most cities, industrial buildings, and plants were devastated.8 Raw materials were scarce, and food and other necessities of life were lacking (Allen 1981). In the 1950s, pushed by economic, social, and institutional reforms of the occupational authorities and demand increases induced by the Korean War, Japan's economy recovered quickly. In the 2 decades that followed Japan's independence in 1952, the Japanese economy grew faster than any other large economy in the world (Allen 1981). This period saw the building of great trunk roads and elevated highways, the modernization of the rail system, and a massive expansion of heavy industry and manufacturing.9 Concrete rapidly replaced the traditional building material of wood, and stocks of built infrastructures increased to several hundred tonnes per capita (Hashimoto et al. 2007; Tanikawa and Hashimoto 2009). Japan experienced a consumption revolution, and material benefits of economic development now also reached rural areas. This triggered rapid physical growth and radical changes in Japan's metabolism. Material and energy use grew much faster than population and even faster than GDP. Per capita material and energy use saw average annual growth rates of 8.5% and 12%, respectively (see table 1 and figure 3), and the share of biomass in DMC declined rapidly (figure 2D). Under U.S. occupation, Japan dismissed its autarky policy and sought integration into international markets. Japan began to import most raw materials and energy carriers. Within less than 20 years, trade dependency for fossil energy carriers and ores surged from almost zero to more than 90% (figure 4). Domestic extraction of these materials, in contrast, peaked and began to decline in the 1960s (see the Domestic Extraction, Trade, and Domestic Material Consumption section of this article). In 1973, material consumption reached an all-time high of 16.5 t/cap/yr, which was six times the pre-WWII level. The share of biomass had declined to less than 10%. Things changed in 1973. Japan, whi