SISTEMAS REGULATORIOS EN BOLIVIA

As a system embedded in the biosphere, human society depends on the natural environment for its subsistence which is enabled by an interrelated process of material and energy transformation (Brunner & Rechberger, 2004; Van der Voet et al., 2013). An analogous notion of biological metabolism emerged in the field of socioenvironmental research to understand society’s transformation in relation to natural environment (Fischer-Kowalski, 1998). The application of metabolism to human society expanded from the catabolism and anabolism metabolic concept to a core analytical concept for understanding material and energy exchange of society with their natural environment (Ayres & Kneese, 1969; Fischer-Kowalski, 1998; Frosch & Gallopoulos, 1989). Although the application of the term metabolism to society can be traced to classic social science research as far back in 1860s, the awareness of anthropogenic environmental changes links with the prevailing trajectory of society’s use of natural resources characterized by unsustainable production and consumption driven by rapid global population and economic growth, expansion of industrial civilization revived the interest in society’s metabolism (Ayres & Ayres, 2002; Brunner & Rechberger, 2004; Fischer-Kowalski, 1998). Abel Wolman (1965) and Robert Ayres & Allen Kneese (1969) made the earlier attempts to developing conceptual framework for analyzing the impacts of human-induced activities on environmental relations. Two broad overlapping field of study have increasingly strengthen the concept of society’s metabolism in contemporary socioenvironmental research. One is the social metabolism, is more general and conceptualize the interaction between the natural environment and the society that covers industrial system and nonindustrial modes of human livelihood (Fisher-Kowalski, 1998). Ayres and Kneese (1969) coined the notion of industrial metabolism and described it as the process of material and energy flows through industrial systems in a thermodynamics framework that operates based on the law of conservation of mass. Ayres and Kneese (1969) argue that industrial transformation processes in the anthroposphere ought to model biological systems in the ecosphere to ameliorate the adverse effect of industrial activities. Their first material flow analysis for the United States between 1963 and 1965 conceived the metabolism of industrial society as an input problem that can be solved through efficient use of material resources (Ayres and Kneese, 1969). Wolman (1965) in his case study of the metabolism of cities in United States, concluded that “the metabolic cycle is not completed until the wastes and residues of daily life have been removed and disposed of with a minimum of nuisance

and hazard” (Wolman 1965 p.179). Comprehensive literature review papers by Fischer-Kowalski (1998) and Fischer-Kowalski & Hüttler (1999) provides detailed information on history and the development of the society’s metabolism concept.

Industrial ecology (IE) emerged as field of study with a goal to understand the structure and operationalize the industrial metabolism (Lifset & Graedel, 2002). As widely acknowledged in various IE literatures, sustainability problems arise from unsustainable material resource production and consumption which is primarily driven by global industrial expansion in the pursuit of economic growth and development (Allen et al., 2009; Ayres & Ayres, 2002; Ciacci, Reck, Nassar, & Graedel, 2015; Graedel, 2011; Harper, Johnson, & Graedel, 2006; Korhonen, 2004; Sendra, Gabarrell, & Vicent, 2007). The sustainable use of resources requires an understanding of the flow of resources from the time of sourcing, through processing, manufacturing or fabrication into other products, use and final destination as waste or reusable resource (National Research Council of the National Academies, 2004). The broader concept for such analysis is called material flow analysis (MFA), a technique used in the field of IE to characterize the flows of a material (for example substances, biotic and abiotic materials, products) through a system or stage of the material life cycle (including extraction, production, transformation, consumption, recycling and disposal) defined in space and time (Ayres, 1994; Ayres & Ayres, 1998; Brunner & Rechberger, 2004; Eurostat, 2012).

Material Flow Analysis (MFA) generally encompasses both substance flow analysis (SFA) and the economic-wide MFA. Both are upheld as representative of the MFA approach (Bringezu et al., 1997; Kleijn et al., 1999; Daniel & Moore, 2002) SFA is a specific brand of MFA that focuses on substance while Economy-wide MFA focuses on flows of ‘bulk’ material throughput through firms, sectors and geographical areas (M. Fischer-Kowalski et al., 2011). MFA is guided by the law of conservation of matter and uses mass units for quantifying physical material stocks and flows (Brunner & Rechberger, 2004) MFA has led to various insights into connections of material origins, pathways, and intermediary and final disposal in a system, and the identification of inefficiencies within a system (Graedel, 2010; Strothmann, 2013). As an important tool for quantifying the magnitude of material flows in the global economy, economic-wide MFA and SFA studies have informed strategies for sustainable materials management (Allen et al., 2009; Allen, Halloran, Leith, & Lindsay, 2009) including agricultural nutrient management (Qiao, Zheng, & Zhu, 2011), waste and waste treatment (Liu, Tanaka, & Matsui, 2006; Nakamura & Nakajima, 2005; Rotter, Kost, Winkler, & Bilitewski, 2004), process control (Chancerel, Meskers, Hagelüken, & Rotter, 2009), resources production and consumption (Graedel,

2010), recovery and recycling performance (Graedel & et al., 2011; Sibley, 2011), and resource efficiency and dematerialization (Lifset, Eckelman, Harper, Hausfather, & Urbina, 2012; Schandl & West, 2010).The Economy-wide MFA framework is based on socio-economic metabolism, an established approach and has a methodological guideline linking MFA accounts to official statistics (Eurostat, 2012) and assesses the flows and stock of bulk materials (Hinterberger, Giljum, & Hammer, 2003; Fischer-Kowalski & Weisz, 2005; Fischer-Kowalski, et al., 2011).

Compared to the multi-material aggregated in economy-wide MFA, substance flow analysis (SFA) accounts for specific chemically defined substances, commonly elements and chemical compounds (Ayres & Ayres, 2002; Brunner & Rechberger, 2004b). SFA is certainly not a new method of analysis; as presented in pioneering studies, for example to address the metabolism of cities (Wolman, 1965), industries (Ayres & Kneese, 1969; Ayres, 1989) and regional basins (Huntzicker et al. 1972). SFA, as a tool for industrial ecology (IE), informs strategies to operationalize industrial metabolisms. It reflects a systems approach, and in most cases, a life cycle perspective, to trace flows of one substance or group of substances into and out of a system. Thus it illuminates the behaviors of substance flows and stocks that emerge within the system (Harper et al., 2006). Substance flow analysis (SFA) is a quantitative approach to track flows of metals (Chen & Graedel, 2012b), nutrients (Qiao, Zheng, & Zhu, 2011), and complex chemicals (European Environment Agency, 2007) usually originating from biophysical systems (biosphere or geosphere) through the transformation in societal (anthroposphere) metabolism and to the final sink in the biophysical systems (biosphere or geosphere) (Brunner & Rechberger, 2004b).

The next three sub-sections provide a review of SFA and its application to tracking flows of metals. The goal of this literature review is to identify a framework on which to base further research, namely to help characterize the supply chain of tantalum and understand the magnitude and pathways of tantalum flows. Specifically, this review examines the quantitative characterization of metal flows and draws upon salient aspects of SFA, namely the systems perspective and the anthropogenic cycle of metals. Section 2.3.2 provides an overview of the substance flow analysis framework, while identifying methodological differences and knowledge gaps. This section ends with a discussion of the strengths and weaknesses of both SFA and MFA.