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Week 11: Ecological Systems

Summary

This week’s readings all center on the complexity of ecological systems. In chapter one of his book, Spellman attempts to define ecology and its importance in nonecologist terms. First, he traces various definitions of ecology, including the most widely used: “the scientific study of the distribution and abundance of living organisms and how the distribution and abundance are affected by the interactions between the organisms and their environment” (pp. 3-4). The definition he offers for his text, however, focuses more heavily on the relations: “Ecology is the science that deals with the specific interactions that exist between organisms and their living and nonliving environments” (p. 5). Like the Cary Institute’s definition (“The scientific study of the processes influencing the distribution and abundance of organisms, the interactions among organisms, and the interactions between organisms and the transformation and flux of energy and matter”), Spellman’s primary emphasis is on interactions and how those interactions maintain or transform an ecosystem.

Spellman explains that an organism’s ecosystem can be divided into four parts: Habitat and distribution, other organism, food, and weather. Additionally, there are four main subdivisions of ecology:

  1. Behavioral
  2. Population
  3. Community
  4. Ecosystem

He also emphasizes several key points regarding ecology. First, he asserts that no ecosystem can be analyzed in isolation( (p. 4). Next, he explains that ecology is typically categorized according to complexity (p. 5), which results in levels of organization (p.14):

Organs–>Organism–>Population–>Communities–>Ecosystem–>Biosphere

Finally, he emphasizes that each organism in an ecosystem has a specific role, or niche, to fill and “in order for the ecosystem to exist, a dynamic balance must be maintained among all biotic and abiotic factors–a concept known as homeostasis” (p. 15). The rest of chapter one explains how the different elements of an ecosystem all form a network of interrelated components that work together to maintain the ecological balance. He further identifies that energy moves through the system that operates as a cyclic mechanism (p. 17).

In chapter four, Spellman narrows his discussion to focus specifically on population ecology, defining a population system as “a population with its effective environment” (p. 62).  He identifies four major components of a population system: the population itself, resources, enemies, and environment (p. 62). Spellman identifies key principles and mathematic formulas for understanding population growth and reduction, highlighting the importance of ecological equivalency (p. 62) and the properties of populations (pp. 63-64):

  1. Population size
  2. Population density
  3. Patterns of dispersion
  4. Demographics
  5. Population growth
  6. Limits on population

 

From Mr G's Environmental Systems: http://sciencebitz.com/?page_id=41

From Mr G’s Environmental Systems: http://sciencebitz.com/?page_id=41

While he spends a lot of time on the laws of population ecology, the key factors of this chapter in terms of our networks class are his explanations of how limits (and lack of limits) affect population growth, his proposed methods for studying populations, and his explanation of how distribution occurs in an ecosystem. When all populations in a a given ecosystem are in balance, he explains, the ecosystem is balanced. Ecological succession is a key component of ecological balance. Succession allows an ecosystem to “heal” itself once the unbalancing factors are removed or overcome.

 

This concern for ecological balance seems to be at the forefront of Guattari‘s argument (my book has been on backorder and should arrive tomorrow, so I’ve read several summaries in the meantime). Guattari seems concerned with what we can understand about existence as a society rather than simply an objective observation of interrelations: “Ecology in my sense questions the whole of subjectivity and capitalistic power formations” (qtd. in Sytaffel). Sytaffel explains Guattari’s argument for an ecosophy that contrasts “a capitalist system predicated on economic growth.”

Finally, Syverson expands the theory of ecology from its environmental situation to a metaphorical application to writing, proposing an “Ecology of Composition.” Current theories of writing, she argues, do not account for the complex systems of writesr, texts, and audiences. Complex systems, she explains, are simultaneously spontaneous, self-organizing, adaptive, dynamic, unpredictable, disordered, and structured, coherent, and purposeful, they better reflect the network of agents that constitute the act of writing. This approach, Syverson explains, “takes into account the complex interrelationships in which the writing is embedded” (p. 6). To fully explain the metaphor, Syverson highlights key concepts from ecology and applies them to composition: distribution, emergence, embodiment, and enaction.

Syverson then breaks the theory down into the dimensions of complex systems to better illustrate “how the attributes of distribution, emergence, embodiment, and enaction can be revealed in ecologies of composing” (p. 18):

  1. Physical-material (including technology): “Texts emerge through writers’ and readers’ physical interactions with material structures” (p. 18)
  2. Social (inter-individual): encompasses not only the interactions between individuals but also social structures, practices, and relationships (p. 19_
  3. Psychological (intra-individual): the thoughts, emotions, neurophysiology of attention, language recognition, and text comprehension involved in writing (pp. 19-20)
  4. Spatial: Texts are composed across both bounded and unbounded spaces (p. 20)
  5. Temporal: discourse is historically and culturally situated (pp. 20-21)

Syverson concludes by emphasizing the need for a comprehensive theory of composing, pointing out that current theories neglect different dimensions revealed through this ecological metaphor.

Discussion

Spellman’s discussion of population diversity  and succession and Guattari’s emphasis on the human capitalist impact on the environment, made me think of the History Channel’s show, Life after People. In this clip form the episode on Chernobyl, we see how quickly the environment begins to heal itself when devastated then abandoned by humans:

The discussions of ecology have been interesting for me (especially Syverson) in that they have provided me a new way of considering new media composing. In her chapter, Syverson discusses the concept of emergence, which seems to tie with earlier conversations regarding genre and discourse. She claims that “to get a comprehensive understanding of composition, we need to understand how distribution , emergence, and embodiment are enacted through activities and practices in composing situations” (p. 13). Combined with Gibson’s theory of affordances and Norman’s theory of perceived affordances, this approach seems useful in beginning to understand the act of composing new media. As a result, I’m now going to look at adding this approach to my reading list.

 

Key Terms

Abiotic Factor: nonliving or inorganic substances such as oxygen and carbon dioxide

Biotic Factor: the living part of the environment composed of organisms that share the same area, are mutually sustaining, interdependent, and constantly fixing, utilizing, and dissipating energy (Spellman, p. 20)

Carrying Capacity: the optimum number of species’ individuals that can survive in a specific area over time (Spellman, quoting Enger, Kormelink, Smith, and Smith, 1989, p. 70). Two types: ultimate and environmental

Community: includes all of the populations occupying a specific area (Spellman, p. 20)

Complex Systems: a network in which independent agents act and interact parallel with each other, simultaneously reacting to and co-constructing their own environment (Syverson, p. 3)

Density-dependent Factors: the effect of the factor on the size of the population depends upon the original density or size of the population

Density-independent Factors: ones where the effect of the factor on the size of the population is independent and does not depend upon the original density or size of the population (p. 68)

Distribution: processes–including cognitive processes–are distributed; both divided and shared among agents and structures in the environment (Syverson, p. 7)

Ecological Succession: the observed process of change in the species structure of an ecological community over time; a gradual and orderly replacement of plant and animal species that takes place in a particular area over time (Spellman, p. 76)

Ecosystem: the community and the nonliving environment functioning together as en ecological system (Spellman, p. 20)

Egress: emigration or departure of an organism from a population (Spellman, p. 67)

Embodiment: the content and process of interactions are dependent on and reflective of physical experience (Syverson, p. 12)

Emergence: the self-organization arising globally in networks of simple components connected to each other and operating locally (Syverson, p. 11)

Enaction: the principle that knowledge is the result of an ongoing interpretation that emerges through activities and experiences situated in specific environments (Syverson, p. 13)

Homeostasis: a natural occurrence during which an individual population or an entire ecosystem regulates itself against negative factors and maintains an overall stable condition (Spellman, p. 20)

Ingress: immigration or arrival of a new organism to a population from other places (Spellman, p. 67)

Mortality: death rate (Spellman, p. 67)

Natality: birth rate (Spellpam, p. 67)

Species Diversity: a measure of the number of species and their relative abundance (Spellman, p. 75)

References

Spellman, F. R. (2008). Ecology for nonecologists. Lanham, MD: Government Institutes.

Syataffel. (Oct. 7, 2008). The three ecologies–Felix Guattari. Media ecologies and digital activism. Retrieved from http://mediaecologies.wordpress.com/2008/10/07/the-three-ecologies-felix-guattari/

Syverston, M. A. (1999). Introduction: What is an ecology of composition? The wealth of reality: An ecology of composition. Carbondale: S Illinois University Press.