Environmental and Resource Systems: Editors’ Introduction Robert Y. Cavana and Andrew Ford Previous Work System dynamics has been applied to a wide variety of environmental and resources systems. One of the earliest applications occurred shortly after Dynamo became available in the 1960s. The problem was declining harvest of salmon in the Pacific Northwest. Researchers at the University of Washington used a Dynamo model to explain the over-investment in “gear” that contributed to the declining harvest (Paulik and Greenough 1966; Watt 1968). The most widely know application is probably the collection of models associated with the study of population growth in a world with finite resources (Forrester 1971; Meadows et al. 1972, 1973, 1974, 1992). Some of the recent applications are described in a special issue of the System Dynamics Review devoted to celebrating the life of Dana Meadows (Sterman 2002). Many of the applications are listed in the bibliography of the System Dynamics Society (2003). Figure 1 reveals the distribution of citations with key words “environmental” or “resource” over the time period from 1960 to 2002. There are 635 citations, approximately 10% of the total publications in the 2003 bibliography. The number of publications increased in the early 1970s, probably as a result of the tremendous interest in the collection of models associated with Limits to Growth (Meadows et al. 1972). Figure 1 shows around ten citations per year during the 1980s and early 1990s followed by a dramatic increase at the turn of the century. The appearance of 70-80 annual citations in the past few years is certainly a dramatic development that might be attributed to growth in the System Dynamics Society, a growing awareness of environmental problems, and the interest generated by the theme ‘Sustainability in the Third Millennium’ (Davidsen et al. 2000) of the 18th International Conference of the System Dynamics Society held in Bergen, Norway. The surge of interest is also supported by publication of special issues of the System Dynamics Review devoted to sustainable development (Saeed and Radzicki 1998) and to “The Global Citizen” (Sterman 2002), and other initiatives like the establishment of the Environmental Dynamics Special Interest Group of the System Dynamics Society by Tasso Perdicoulis1. Figure 2 provides further analysis of the number of environmental and resource publications during the past four decades. This chart shows that energy and resource applications dominate the frequency of citations. Resource applications cover a lot of ground, so it is reasonable for this key word to extract a large number of citations. Energy issues have received major attention of system dynamics practitioners, as explained by Ford (1999) and by Bunn and Larsen (1997). Figure 2 shows a significant number of citations for more narrowly defined key words such as fisheries and earth systems. 1 Environmental & Resource Publications 90 80 70 60 50 40 Number 30 20 10 0 60 63 66 69 72 75 78 81 84 87 90 93 96 99 02 Year Figure. 1. Number of publications listed in the System Dynamics Society bibliography extracted using the keywords ‘environmental’ or ‘resource.’ SDS Bibliography keyword frequency resource 486 energy 372 environmental 178 population 146 water 112 sustainable 108 natural resource 84 forest 74 ecology 69 Keyword agriculture 67 pollution 42 fish 37 waste 28 earth 26 climate 17 wildlife 5 0 100 200 300 400 500 Frequency Figure. 2. Analysis of System Dynamics Society 2003 bibliography by keyword frequency 2 The citation analysis shows a tremendous quantity of work, and these citations are mostly limited to those who elect to publish their models in the system dynamics literature. The number of citations would be even greater if we were to count the many modelling applications using system dynamics software such as Stella. These citations would include, for example, work by Costanza and Ruth (1997), Costanza (1998), Saysel and Barlas (2001) and the text by Grant et al. (1997). Counting such applications in the analysis would reinforce the trend evident in Figure 1. There is a major surge in interest in the application of system dynamics methods to environmental and resource systems. We now consider the quality of applications. Since we are interested in pragmatic applications, the ultimate measure of quality is success in model implementation and in shaping decisions and attitudes about the environment. From an academic perspective, an important indicator of quality is the Jay Wright Forrester Award. This award is granted up to once a year for the best contribution to the field of System Dynamics. The award was first granted in 1983, and there have been 18 awards through the year 2003. Four of the awards have honoured publications on environmental and resource systems: • The 1991 award went to Dennis Meadows for the development of model- based games such as “Stratagem.” (Stratagem is a game to help national leaders plan development with limited resources, available from the University of New Hampshire http://www.unh.edu/ipssr/Lab/Stratagem.html.) • The 1995 award honoured Khalid Saeed’s (1991) work on modelling of sustainable development and for his book on Towards Sustainable Development: Essays on System Analysis of National Policy. • The 1996 award honoured the work on electricity and conservation modelling by Andrew Ford (1990), as reported in an Operations Research article on uncertainty in the northwest electric system. • The most recent award-winning work on environmental problems went to Erling Moxnes for his experiments on a cod fishery with Norwegian subjects. The award-winning article was published in Management Science , “Not Only the Tragedy of the Commons: Misperceptions of Bioeconomics” (Moxnes 1998). The Moxnes fishery experiment is the most relevant to this special issue, and it merits additional description. The experiment builds from the widely used “Fish Banks, Ltd” game by Meadows, Fiddaman and Shannon (1989). Participants in the Fish Banks exercise allows participants to compete for harvest in an ocean fishery with open access. The participants typically over-invest in boats, deplete the fish populations and grow to appreciate how their own decisions lead to the “tragedy of the commons.” Moxnes builds upon these findings in an experiment with Norwegian subjects operating a cod fishery with monopoly ownership. (Moxnes granted the subjects ownership to avoid the open access problem.) Consequently, his participants were able to avoid depleting the fish population, but they exhibited a strong tendency to over-invest in the number of boats. Moxnes documented this pattern and compared it to a similar pattern of over-investment in Norwegian fleets. 3 The tendency for decision makers to over-invest in capacity to exploit renewable resource is a chronic, serious problem that limits our ability to manage renewable resources in a sustainable, efficient manner. The problem is well-known in fisheries, where Clark reports that investment in fishing capacity is often “much larger than twice the optimum level” (Clark 1985, p. 7). Over-investment also contributes to problems of sustainable management of forests, of watersheds and in grazing systems, as will be explained in articles in this special issue. History and Purpose The special issue has been under discussion and development over the past three years. We volunteered as guest editors because of our own interests in resources and the environment (Cavana 1984, 1996, 2003; Ford 1990, 1996, 1999). Our call for proposals was answered with over thirty proposals from researchers around the world. We received a truly impressive collection of proposals dealing with water resources, fisheries, forest management, energy consumption, land degradation, air pollution and conflict resolution. The quantity and quality of the proposals is further evidence to confirm the surge of interest shown in Figure 1. The purpose of the special issue is to share examples of pragmatic applications of system dynamics modelling of important environmental and resource systems in a single issue. We have asked each of the authors to make their models available so that other researchers can build from their work. The models described here have been carefully documented, both in the papers and in the model files, which can be downloaded from a website devoted to the special issue (http://www.wsu.edu/~forda). 4 Comparison of Papers Table 1 provides a summary of the papers. We report the authors, models, location of the case studies and the issues under consideration. Table 1 then summarizes the models’ purposes and the clients for whom the models were constructed. Martinez Faust, Jackson, Arquitt Author(s) Dudley Fernandez & Moxnes Ford, Earnhardt & & Johnstone Esteve Selma Thompson Model Log export ban Irrigated landscapes Misperception of. Wildlife population Blue-green algae blooms feedback management (spectacled & grizzly bears) Geographic Forests in Irrigated lands in SE Reindeer rangelands AZA zoos, & Greater Coastal waters of location Indonesia Spain of Norway Yellowstone Queensland, Ecosystem, USA Australia Issue(s) Substantial New irrigated lands Over use of Improved management Algae blooms threatens increases in illegal leading to renewable resources & conservation of water quality, coastal logging & overexploitation of due to wildlife populations in ecosystems & harmful to deforestation available water misperceptions of captivity & natural humans resources the dynamics habitats Model To understand