The Nexus between Energy, Food, Land Use, and Water
Application of a Multi-Scale Integrated Approach

What MuSIASEM is

  • The Nexus Assessment Project was commissioned by the Energy Team of the Climate, Energy and Tenure Division (NRC) of the UN Food and Agriculture Organisation (FAO)

    and sponsored by the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ).

The Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) is an innovative approach to accounting that integrates quantitative information generated by distinct types of conventional models based on different dimensions and scales of analysis.  It builds on several innovative concepts derived from Bioeconomics and Complex Systems Theory, such as the flow-fund model, multi-purpose grammars and impredicative loop analysis.  The application of these concepts allows the simultaneous use of technical, economic, social, demographic, and ecological variables in the analysis of the metabolic pattern of modern societies, even if these variables are defined within different dimensions of analysis and non-equivalent descriptive domains and refer to different hierarchical levels and scales. Given this special feature, MuSIASEM allows us to effectively analyze the nexus between energy, food, and water, considering heterogeneous factors such as population dynamics, greenhouse gas (GHG) emissions and land-use changes at the national or sub-national level. The accounting system is able to integrate data from national statistics and/or other readily available datasets (e.g., FAO Food Balance Sheets) with data from Geographic Information Systems (GIS). It can be employed for diagnostic as well as for simulation purposes.

As diagnostic tool, the accounting system is used to characterize the existing metabolic pattern of the socio-economic system under analysis by providing integrated information on:

  1. Population, work force, technological capital, managed land, and total available land (defined as fund elements);
  2. Flows of food, energy, water, and money (defined as flow elements).  For each of these flows we define the total requirement, the fraction for internal consumption, the losses, the degree of self-sufficiency (internal supply), and imports and exports.
  3. A series of flow/fund ratios characterizing the rate (per hour of human activity) and density (per hectare of managed land) of the above flows across different scales (including the whole society and each one of the lower-level compartments defined in the accounting scheme, such as the various economic sectors). These ratios are then compared against reference values describing ‘typical’ socio-economic systems. 

As simulator tool, MuSIASEM provides a feasibility, viability, and desirability check of proposed scenarios.  In fact, the approach allows us to:

  1. Check the feasibility of proposed scenarios by looking at the compatibility of the system with the boundary conditions. These external constraints are checked by comparing the required local flows to both the supply and sink side of the local interface with the environment. This analysis is obtained by characterizing the required flows (dictated by the internal characteristics of the socio-economic system) with GIS data. The MuSIASEM methodology uses an environmental impact matrix for this purpose;
  2. Check the viability of proposed scenarios by looking at the congruence between the requirement and the supply of flows across different compartments.  This check can be done at different scales after characterizing the rate (per hour) and the density (per hectare) of the various flows in the chosen scenarios.  For example, data on consumption aggregated at the level of the whole society must result congruent with the technical coefficients (e.g. yields, productivity of production factors, requirement of specific processes) describing the supply at local scales. The MuSIASEM methodology uses a multi-level, multi-dimensional matrix for this task and a so-called SUDOKU strategy to check the congruence of values across the different scales and dimensions of analysis;
  3. Check the desirability of viable scenarios by comparing the resulting metabolic pattern (flow/fund ratios) at the level of end-uses (specific functions at the local scale, such as sugarcane production, public transportation) to benchmark values of flow/fund ratios (expected features of the functions expressed) characteristic of given types of socioeconomic systems.