Featured Stories
Fish, gold and pollution: homo economicus vs. homo psychologicus
Can we understand the role of human behaviour in renewable resource exploitation? To explore this question, we constructed an imaginary island called Lakeland, with a local population catching fish for its livelihood, having the possibility to exploit a goldmine and the option to permit large, foreign trawlers to fish in their waters. Based on an underlying system dynamics model (see http://www.sustainabilityscience.eu/2020/local-fisheries-layers-of-overexploitation/), an agent-based model (ABM) was built to better understand the role of heterogeneity in needs satisfaction and risk perception [...]
Free energy flow density as a measure of complexity
The astrophysicist Chaisson (2001) has proposed an interesting link between energy and complexity. Organisms can be viewed as dissipative structures: Ordered objects whose structure can be maintained thanks to a steady input of high-quality energy. The free energy flow density (ɸ) necessary to sustain such a non-equilibrium structure is a measure of complexity. It can be expressed in erg per second per gram or, more commonly, in mW per kg (1 erg = 107 joule). The free energy flows are [...]
The Textbook
Written by prof. dr. B.J.M. de Vries, it provides an integrated, system-oriented introduction to the concepts, theories and issues surrounding the quest for a sustainable future for Planet Earth.Knowledge Base
We are building a knowledgebase of links, institutions and educational material, based on our understanding of sustainability science, as presented in the book.Research & Education Tools
In this section we are collecting interactive tools that can be used for research and teaching.Other Stories from our Blog
Energy: forms, conversions, quality, exergy
Energy forms and conversions
Energy is a fundamental quantity in nature that is transferred between systems or parts of systems. It is ‘stored’ in a variety of forms and is associated with movement, combustion, heat and […]
Energy use: units and flows
Energy use: units
Energy units. It is important to get some familiarity with the units of energy quantities (stocks) and flows. The energy stored in systems is a stock. Examples are the chemical energy stored […]
Energy use: the economics of energy saving
The dynamics behind the changes in material intensity is an important topic in energy economics. Goods and services are produced with a variety of inputs and a so-called production function has been proposed to describe […]
Acquiring knowledge: strong and weak knowledge
Suppose you are concerned about air pollution and set up an experiment to measure the concentration of substance X in a well-defined area. The measuring tool is itself an illustration of scientific development. The result […]
Fishing strategies: an agent-based simulation
Let us consider in more detail an investigation of different harvesting strategies (Brede and de Vries 2009). Let there be a distributed resource consisting of j = 1..P fishing zones, each modelled similar to the […]
Book and Website Reviews
Top-down or bottom-up, that is the question?
Every now and then I meet friends who have given up on changing the world: “It is too complex, too violent, too far away, and I feel powerless in the face of it. So I [...]
A simple introduction to system dynamics for sustainability – a report by Hördur Haraldson
We humans make mental ‘maps’ of processes around us in order to live and survive. Many of those maps are simplified, based on a limited set of acquired habits and experienced events. The maps also [...]
System dynamics for real-world complexity: a book by Erik Pruyt
In 2013, Dr. Erik Pruyt (Delft Technical University) has released a book on system dynamics, titled Small System Dynamics Models for Big Issues: Triple Jump towards Real-World Complexity. It is set up as an interactive [...]
Games for sustainability education, research and policy
One way to explore integration of the natural and the social sciences is the construction and use of simulation games and policy exercises (cf. Chapter 10 and 12). Since 2013 several websites have come online [...]