Mario Giampietro

Feasibility of Large-Scale Biofuel Production

iofuels are widely seen as a feasible alternative to oil. Indeed, in 1995 the Clinton Administration proposed amendments to the Clean Air Act that would require gasoline sold in the nine most polluted US cities to contain additives from renewable sources, such as grain alcohol. This move, even if blocked by a three-judge panel of the US Court of Appeals in Washington, DC (Southerland 1995), has helped to focus attention on the question of whether research and development in biofuel production from agricultural crops should be increased (e.g., Abelson 1995). In Europe, similar fiscal and regulatory provisions have already been introduced (Chartier and Savanne 1992, Sourie et al. 1992). These policies assume that biofuels have the potential to reduce current dependence of industrialized societies on rapidly disappearing fossil energy stocks and that biofuels are desirable from an ecological point of view. But are these assumptions correct?

Multiple-scale integrated assessment of societal metabolism: Introducing the approach

In this paper we present several concepts related to integrated analysis of societal metabolism across scales. First we introduce the concept of “dynamic energy budget” of human societies, which is based on the distinction between exosomatic and endosomatic energy flows and the possibility of establishing autocatalytic loops (egg-chicken patterns) among them. Second, we discuss the nature of the dramatic changes that the industrial revolution induced on the characteristics of societal metabolism. Finally, we discuss methodological problems related to the representation of complex adaptive systems. Dealing with sustainability of human societies requires the parallel use of non-equivalent descriptive domains. This, in turn, requires the ability of “scaling up and down” when moving across levels handling parallel non-reducible assessments.

Multiple-Scale Integrated Assessments of Societal Metabolism: Integrating Biophysical and Economic Representations Across Scales

The crucial challenge for integrated analyses of socioeconomic systems is keeping coherence in their multidimensional representation. Our approach describes the hierarchical structure of socioeconomic systems using the profile of allocation of “human activity” over a set of compartments defined at different hierarchical levels (e.g., whole countries, economic sectors, individual households). Compartments are characterized in terms of intensive variables (“intensity” of both “exosomatic energy flows” and “added value flows” per unit of human activity) and the extensive variable “Total Human Activity” ← → “population.” In this way, relations of congruence across hierarchical levels can be used to link non-equivalent analyses. That is, changes in demographic variables, economic variables, technical coefficients, indices of environmental loading, institutional settings, and social aspirations are no longer independent of each-other even if described within different scientific disciplines.

Using hierarchy theory to explore the concept of sustainable development

Abstract It is commonplace to experience a discrepancy in values when assessing the same phenomenon or action from different perspectives, eg what is good to our taste (assessment on a short-term timescale) may be harmful to our health (assessment on a longer timescale). This pattern is repeated at each enlargement of perspective that brings another hierarchical level into the picture: what is profitable for the family—less taxes—may be harmful to the community. The study of these contrasts has traditionally been addressed by disciplines such as philosophy, political science and ethics. However, the development of hierarchy theory provides us with a scientific tool to explore the nature of the contrasts of values. This article discusses the major principles of hierarchy theory and goes on to consider the issue of sustainable development.

Fossil energy use in agriculture: an international comparison

Abstract This paper is aimed at assessing the comparative importance of constraints in land and labour endowment for energy balance in agriculture, when assessed at the level of national crop production systems. The relation between output/input energy ratio of agriculture (output: food energy in crops; input: commercial energy embodied in technical inputs), average labour productivity (food energy (in Joules) produced per hour of labour allocated to agriculture) and land productivity (food energy (in J) produced per hectare of cropped land) has been studied on a 75-country sample using a cluster analysis procedure. A cross-section equation has been developed, explaining output/input ratio in terms of intensity of land and labour-food-energy throughputs. The results suggest that land constraints, with respect to the total population size, rather than labour constraints, tend to be associated with comparatively higher energy requirements in agricultural production. Therefore, the ‘emancipation’ of agricultural production from land shortages implies two ‘biophysical costs.’ That is, for the production of the same amount of food, a consistent increase in demographic density implies both a larger consumption of fossil energy input and a larger environmental impact.

Energy analysis of agricultural ecosystem management : human return and sustainability

Abstract The objective of this paper is to present a different perspective in energy analysis of ecological and agricultural systems. A set of parameters derived from energy analysis is proposed to examine the ecological aspects of agricultural management. In this way cost/benefit analysis can be extended also to the ‘biophysical capital’ responsible for the sustainability of agricultural production. The text is divided into parts: first, the basic concepts related to the thermodynamics of biophysical systems are examined to provide a theoretical framework; second, numerical examples illustrate the assessment of the trade-offs between ecosystem stability and human return in food production when natural ecosystems are altered.

Technological changes in energy use in U.S. agricultural production.

Energy is equally important to land, water, and human resources in U.S. crop production. In addition to human energy, sunlight and fossil energy are the primary energy resources utilized in agricultural production. Because all technologies employed in agriculture require energy resources, the measure of energy flow in crop production provides a good indicator of the technological changes that have taken place in this sector. Energy values (kilocalories) for various resources and activities remain constant, and this is a major advantage in assessing technological change in agriculture, in contrast to economic values that are continually changing depending on the relative supply and demand of various resources and services. Another advantage of using energy as a measure of change in agricultural technology is that it can help assess the substitution of different forms of energy for various practices, as well as the substitution of land, water, and labor resources for energy.

Socioeconomic constraints to farming with biodiversity

Abstract Technological development in agriculture has led to a diminished use of biodiversity in food production, and a reduced efficiency of energy use. This paper explores the reasons for these paradoxical effects of progress, by considering the farming system as an integral part of the larger socioeconomic system and natural environment in which it operates. Whenever changes in the socioeconomic and demographic characteristics of society result in a higher opportunity cost of labor, land and capital, the agricultural sector has no other option but to augment the productivity of labor, land and the economic return of capital investments. At the farm level, this translates into the need to increase the density of agricultural throughputs, per hour of farm labor and per hectare of land, in the agroecosystem. Above a certain threshold, high densities of agricultural throughputs can no longer be achieved with natural patterns of matter cycling in the agroecosystem. Fossil energy inputs and monoculture then become a necessity. The relationship between socioeconomic and demographic characteristics on the one hand and actual productivity of labor and land in agriculture on the other hand is confirmed by a cross-sectional analysis of a large sample of countries. General trends in economic and population growth indicate that most countries are moving toward high-energy-input and labor-saving technologies. Moving away from this path of technological development in agriculture, as would be required to preserve and enhance biodiversity use in agriculture, is an immense challenge that needs to be faced.

Assessment of the energetics of human labor

Abstract The energetic analysis of farming systems implies an assessment of the energetics of human labor. The energy cost of 1 h human labor is generally estimated according to its physiological requirement (the hierarchical level at which the assessment is made is at the individual level). A different way of describing the interaction between human society and the ecosystem is presented in this paper (assessment referred to the society level). The shift from the individual level to the societal level provides a new perspective when assessing the energetic efficiency of farming. For example, the power level of the system becomes a new and important parameter to consider. Numerical examples illustrate the proposed approach.

Sustainability and technological development in agriculture

he frightening demographic trend faced by humankind, rapid growth of the already massive human population, is demanding technological breakthroughs in agricultural production. Genetic engineering might appear to be the natural candidate for this job. However, changes made possible by genetic engineering have to be assessed in relation to the sustainability of human development. It is therefore important that, besides physical efficiency and economic viability, any assessment of biotechnology or other agricultural advances include a check on its com-