Static/dynamic ecological modeling systems

Justin R.

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Static/dynamic ecological modeling systems

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Ecological modeling is utilized as a predictor mechanism, to ultimately analyze and observe the various systems and process which govern an ecosystem. With this information available, scientists can attempt to alter an ecosystem based on the interactions of several variables. These models essentially define an ecosystem mathematically; calculating and interpolating the relative rates and probabilities of various natural processes. (Jorgensen, 2008).Some models rely completely on the basis of survivorship; that is, the relative proportions of life and death within a species population. These analyses can be carried out as representations of the survivorship patterns of a species, and can therefore be utilized to determine whether or not a population is in decline or increasing. (Molles & Cahill, 2008) This static method is especially useful when monitoring our rates of harvest towards specific resources. Static model are designed as a means to analyze the survivorship of a species based on several discrete variables. (Moles & Cahill, 2008) This method of analysis has been applied to the harvesting of shrimp by commercial fisheries. In order to ensure that a sustainable system is maintained, it is essential to determine a level of harvesting which allows the shrimp populations to remain at a healthy state. Furthermore, as a result of the harvesting, various other species are captured in the process, and must be accounted for. The hawksbill turtle is often a victim of this process, as their populations may be significantly reduced by the relative rates of capture. (Waltho, 2008) This investigation aims to determine whether these species are being harvested in a sustainable manner, or if the rates of harvest require alterations to ensure the survival of the species

Introduction
The term mentor according to the English National Board
The standard for communication and working relationships
Factors which may affect learning
The Gestalt theory
The importance of the mentor's role in assessing practice
Conclusion
Bibliography

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[...] (Jorgensen, 2008) With the collaboration of realistic data, and their respective variables, an ecological regime can be generated to help restore the diversity of an otherwise damaged ecosystem. Results: The static model of analysis yielded several values pertaining to the relative survivorship characteristics of both the shrimp and hawksbill turtle populations. It was determined that at a net reproductive rate of 2.6 female offspring per single adult female, a generation time of 1.04 years, and a maximum rate of increase of 0.92 individuals per years, the maximum sustainable yield for shrimp was approximately 230,000 individuals. [...]

[...] This model, if acted upon, would most likely contribute to the extinction of the species, and must therefore allow for alternate variables to approach ecological accuracy. The utilization of a dynamic modeling system also presented various difficulties. This system was designed to test the effects of fires, herbivory, and predation of the diversity of an ecosystem. Initially, the system was run to detail the effects of controlled burns. Without the inclusion of fires, several species were capable of out-competing all others, until a monoculture of hickory trees was all that remained. [...]

[...] (Molles & Cahill, 2008) If the intraspecific competitive nature of theses organisms was accounted for, we would expect to see a system more relative of the intermediate disturbance hypothesis. The intermediate disturbance hypothesis also assumes that the levels of disturbance occur in a uniform manner, although realistically, low level disturbances generally occur quite frequently while higher levels disturbances are rare. (Cordonnier, et.al. 2006) Without this indication of rate, the intermediate disturbance hypothesis lacks a fundamental concept in the optimization of ecological systems. References: Brewer, D. Dell, Q. Fry, G. Heales, D. Jones, P. Milton, D. Venables, B. (2006) The impact of turtle excluder devices and bycatch reduction [...]

[...] This system maintained a health state for upwards of 400 years, and withheld a high level of diversity. This model relies on several assumptions which may render its predictive nature inadequate. Each species had a very limited choice of resources for consumption, and constantly relied on the same resources. In order to account for the effects of natural processes, the model relied completely on the basis of probability. Although this may account for the average frequency of these events, it does not relative any form of random variation. [...]

[...] After manipulating the frequency and magnitude of the fire, the optimal diversity was found at midrange. These fires were relatively large, yet provided the forest with regions to implement new growth on a fairly regular basis. This was especially important with the inclusion of moose. Initially, the fires would kill off almost the entire population of moose either by directly killing them, or all local food sources. This was accounted for by simply increasing the prominence of fires, while reducing the overall magnitude. [...]

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