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Displaying 1 - 15 of 29 records found.
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A model of robustness tradeoffs in social-ecological system

Model
Feedback control systems in general exhibit inherent robustness-fragility tradeoffs. That is, by becoming very robust to a given set of disturbances for maintaining stability, feedback systems necessarily introduce hidden fragilities to disturbances outside this set. Even a small unanticipated disturbance can initiate cascading system-wide failures as a result. The model presented here demonstrates this phenomenon. In Anderies et al. (2012), an agricultural production system is illustrated as...
09 Aug 2016

A Two-Sector Growth Model: Economic Development, Demographics, and Renewable Resources

Model
This is a two-sector growth model that couples the dynamics of human demographics and a renewable resource base. The two sectors are agricultural and manufacturing sectors. To capture both the positive (Malthusian) and negative (modern growth) type relationships between population growth and output, it is important to model the shifting composition of output from agricultural to manufacturing as growth occurs. Thus, the model is a two sector (productions and consumptions in...
09 Aug 2016

Agave Cultivation in the Arid Pre-Hispanic, Villanueva Municipality, state of Zacatecas, northern Mexico

Case
Agave is a perennial plant that can be used for multiple purposes: as edible materials for yielding caloric values and as fiber materials for producing items like clothing, ropes, and baskets. Historical records indicate that the cultivation of agave was a common practice in pre-Hispanic Northern Mexico and the American Southwest. It is generally accepted among archeologists that the agave cultivation was linked to the strategy of ensuring food supply when maize cropping failed from droughts....
09 Aug 2016

Analyzing the Impact of Agave Cultivation on Famine Risk in Arid Pre-Hispanic Northern Mexico

Model
Here, a simple model of a subsistence economy based solely on the cultivation of maize and agave is presented. While maize is an annual plant that humans can eat and store, agave is a perennial plant that can be used for multiple purposes: as edible materials yielding caloric values and as fiber materials for producing items like clothing, ropes, and baskets.  This model tries to capture the essence of a cultivation strategy of a portfolio of plants that have differing levels of sensitivity...
09 Aug 2016

Conflict between groups of players in coupled socio-economic and ecological dynamics

Case
Conflict among multiple groups is a major source of difficulty in environmental conservation. People are often divided into various groups that have different social factors, sometimes leading to differences in the degree to which they cooperate in environmental conservation. This obstructs the social consensus needed to solve the environmental problems. Here we study the coupled dynamics of human socio-economic choice and lake water pollution, and examine the magnitude of the difference in...
09 Aug 2016

Conflict between groups of players in coupled socio-economic and ecological dynamics

Model
This is a model for the coupled dynamics of conflict between two different user groups regarding their socioeconomic choice (between cooperative and non-cooperative collective action) and nutrient loading input level into a lake water system. Suzuki and Iwasa (2009),gives the following overview of the model. "Conflict among multiple groups is a major source of difficulty in environmental conservation. People are often divided into various groups that have different social factors, sometimes  ...
09 Aug 2016

Culture and Human Agro-ecosystem Dynamics: the Tsembaga of New Guinea

Model
The model of Tsembaga agro-ecology explores the coupled dynamics involving population growth, renewable resource base, resource consumption by humans, and the self-regulating effect of cultural ritual. The model demonstrates that the cultural ritual of Tsembaga (Kaiko) can stabilize the Tsembaga population and its resource level. This is achieved by attenuating wildly fluctuating limit cycles of population and resource levels down to desirable small-amplitude cycles. Anderies (1998) describes...
09 Aug 2016

Lorenz Model

Model
This simple model was developed by Edward Lorenz in 1963 to study fluid mechanics (based on Navier-Stokes equations). It is the first ever model of a chaotic dynamical system. Chaos arises when a deterministic, nonlinear dynamical system exhibits long-term unpredictability in behavior due to sensitivity to initial conditions.The model is a three-dimentional system of differential equations. Specifically, the model describes the convection motion of a fluid in a small idealized "Rayleigh-...
09 Aug 2016

Non-linear dynamics of population and natural resources: The emergence of different patterns of development

Model
This model explores the long-term dynamic interaction between the exploitation of natural resources and population growth. This is a variant of Brander and Taylor (1998). The reference article, D'Alessandro (2007), gives the following description of the model. "Two new assumptions are introduced: i) the disaggregation of the ecological complex into two different resources; ii) irreversibility —namely, an inexorable tendency to exhaustion when the renewable resource stock is below a certain...
09 Aug 2016

Paradox of marine protected areas: suppression of fishing may cause species loss

Case
This is a placeholder case for the model for the same name. Please revise case information to reflect the case study represented in the model.
09 Aug 2016

Paradox of marine protected areas: suppression of fishing may cause species loss

Model
This is a simple model of a prey–predator system in two areas, one of which receives fishing activity (fishing ground) and another that does not (MPA: marine protected area). Takashina et al. 2012 gives the following description of the model. "A number of fish and invertebrate stocks have been depleted by overexploitation in recent years. To address this, marine protected areas (MPAs) are often established to protect biodiversity and recover stocks. We analyzed the potential impact of...
09 Aug 2016

Regime shifts in a socio-ecological model of farmland abandonment

Case
Figueiredo & Pereira (2011) developed a mathematical model with two-way linked socio-ecological dynamics to study farmland abandonment and to understand the regimes shifts of this socio-ecological system. The model considers that migration is a collective behavior socio-economically driven and that the ecosystem is dynamic. The model identifies equilibria that vary from mass migration, farmland abandonment, and forest regeneration, to no migration and forest eradication; partial migration...
09 Aug 2016

Regime shifts in a socio-ecological model of farmland abandonment

Model
This is a simple model with reciprocal feedbacks between social and ecological dynamics of farmland abandonment. With the rising urbanization, human migration to urban centers have increased significantly around the globe. One notable consequence of this migration pattern is that mountainous forests that had been traditionally cleared for farming are increasingly becoming abandoned. As a result, such lands likely become forests again through natural regeneration. These trends may induce two...
09 Aug 2016

Robustness and Resilience across Scales: Migration and Resource Degradation in the Prehistoric U.S. Southwest

Case
Migration is arguably one of the most important processes that link ecological and social systems across scales. Humans (and other organisms) tend to move in pursuit of better resources (both social and environmental). Such mobility may serve as a coping mechanism for short-term local-scale dilemmas and as a means of distributing organisms in relation to resources. Movement also may be viewed as a shift to a larger scale; that is, while it may solve short-term local problems, it may...
09 Aug 2016

Robustness and Resilience across Scales: Migration and Resource Degradation in the Prehistoric U.S. Southwest

Model
This is a simple model that integrates 1) resource-population dynamics, 2) population migration, and 3) spatial heterogeneity in biophysical conditions (i.e., soi fertility). The reference article, Anderies and Hegmon (2011), gives the following abstract of the model. "Migration is arguably one of the most important processes that link ecological and social systems across scales. Humans (and other organisms) tend to move in pursuit of better resources (both social  and  environmental).  Such ...
09 Aug 2016