Ecological Anthropology

BALI WATER TEMPLES:

The Water Priest's Apprentice This game is based on field studies, research and a computer program by Stephen Lansing and James Kremer. (For a more detailed explanation see this article.)

http://www.sacredbalance.com/web/pond/

BEAVER ECOLOGY:

Life Cycle of a Beaver Pond

ECOLOGICAL DEFINITIONS:

Biocomplexity

The notion of expresses the understanding that properties emerge from the interplay of behavioral, biological, chemical, physical, and social interactions that affect, sustain, or are modified by living organisms, including humans.

Biocomplexity

The interplay between life and its environment is complex. Biocomplexity arises from the multitude of behavioral, biological, social, chemical, and physical interactions that affect, sustain, or are modified by living organisms, including humans. From cells to cities to the global ecosystem, all systems associated with life exhibit biocomplexity. Characteristics of biocomplexity include: -nonlinear or chaotic behavior -interactions that span multiple levels or spatial and temporal scales -hard to predict {unpredictable behavior} -must be studied as a whole, as well as piece by piece -relevant for all kinds of organisms -- from microbes to human beings -relevant for environments that range from frozen polar regions and volcanic vents to temperate forests and agricultural lands as well as the neighborhoods and industries of urban centers. Research on biocomplexity asks questions such as: How do systems with living components (such as people) respond and adapt to stress? Are adaptation and change predictable? How will climate change affect species’ ranges? Can we forecast the combined effects of changing climate and socioeconomic change? How does diversity (species, genetic, cultural) affect system stability?

Biocomplexity arises from the multitude of behavioral, biological, social, chemical, and physical interactions that affect, sustain, or are modified by living organisms, including humans.

Biodiversity:

(a) The number and variety of organisms found within a specified geographic region.
(b) The variability among living organisms on the earth, including the variability within and between species and within and between ecosystems.

Biogeography:

The geographic distribution of organisms. [American Heritage Dic. of the English Language, 4th ed.]

Community ecology:

A field of study concerning community-based ecological theory, temporal and spatial dynamics, and trophic interactions. [Adapted from Community Ecology journal, <http://www.terra.hu/comecol/>]

Ecological Succession (excellent source of ecology terms)

(a) One thing that limits the carrying capacity for many organisms is that the presence of these organisms essentially spoils the environment for their continued presence.

(b) Such organisms typically are r-selected, and essentially are good at finding environments they can exploit, exploiting those environments, then giving way to organisms which are better at hanging on in those environments.

(c) The exploitation of an environment by one population, followed by the exploitation by a second (third, etc.) population is termed ecological succession.

(d) "Many of the changes in community structure during succession may be induced by the organisms themselves. Direct biotic interactions may be involved, including inhibition of some species by others through exploitative competition, interference competition, or both. The presence of organisms also affects the abiotic environment by modifying local conditions. This may result in facilitation, in which the group of organisms representing one stage 'paves the way' for species typical of the next stage . . . Sometimes the changes that facilitate the development of a later stage actually make the environments unsuitable for the very species responsible for the changes."

(e) Ecological succession continues in a habitat until species, typically K-selected, that are good at nurturing their young within the same environment (as well as good at excluding other species) comes to dominate the environment, or until catastrophic change essentially wipes the slate clean, making an environment once again exploitable to the r-selected populations.

Human ecology is the study of how human social systems relate to and interact with the ecological systems on which they depend. (Human Ecology: Basic Concepts for Sustainable Development. Gerald G. Marten. Sterling, VA : Earthscan Publications, 2001.)

Population and community ecology

Interactions of a single species (population) or an association of different species (community) occupying a particular region with their biotic and abiotic environments.

Population ecology is a science that deals with measuring changes in population size and composition and identifying the factors that cause these changes.

Resilience (Ludwig, Walker, and Holling 1973)
...natural systems are resilient, i.e., they tend to maintain their integrity when subject to disturbance.
...stability refers to the tendency of a system to return to a position of equilibrium when disturbed.

Resilience
The speed with which a disturbed system returns to equilibrium or the same general sstate after being changed (Smith1996).

Resistance
The ability of a system to withstand or resist variation (Smith 1996).

Intermediate Disturbance Hypothesis
In non-equilibrium communities highest disversity is maintained at an intermediate level of disturbance (Connell 1978). "At a high frequency of disturbance, there is no time for certain species to mature. The community is dominated by species with a rapid growth rate, a short life span, and a strong ability to colonize disturbed areas [annuals]. At a low frequency of disturbance, short-lived species are outcompeted by long-lived species that come to dominate the community. Diversity is low, however, within the two extremes, as the time between dissturbances lengthens, species of varying rates of growth, longevity, and competitive abilities can persist. Further influencing the process is the scale of disturbance. Small-scale distrubances favor higher diversity than large-scale ones. Overall, small-scale environmental disturbances at intermediate frequencies best maintain diversity in communities (Smith 1996:653)."

(Smith 1996:653)

Working Definitions of Robustness

1. Robustness is the persistence of specified system features in the face of a specified assembly of insults. [See e.g. Allen "Ecosystems and Immune Systems".]
2. Robustness is the ability of a system to maintain function even with changes in internal structure or external environment. [See e.g .Fontana and Wagner ``Mutational Robustness"; M. Sheetz, ``The Cell as a Machine"; Callaway et al "Network Robustness and Fragility"; Scientific Committee on Antarctic Research"Regional Sensitivity to Climactic Change in Antarctic Terrestrial Ecosystems".]

Stability

Stability – A system is stable if and only if the variables all return to initial equilibrium state after a perturbation (Pimm 1986) {a mathematical definition of stability} 4 components: Resilience – speed of return to equilibrium Persistence – the time a variable lasts before changing to a new value Resistance – how large a disturbance is needed to perturb system Variability – the normal range of values at equilibrium

Ecology and Evolutionary Biology:
Trophic structures are the feeding relationships within communities and therefore within ecosystems, that is, who's eating whom. Trophic levels refer to how far removed from the original source of energy an organism is within a trophic structure.

Variability

The power possessed by living organisms, both animal and vegetable, of adapting themselves to modifications or changes in their environment, thus possibly giving rise to ultimate variation of structure or function. (American Heritage Dict).