Communities & Ecosystems

 

Levels of Biological Studies

Description and examples of biological study – Biosphere, ecosystems, populations, organisms, and cells.

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Overview of Ecology

Overview, history, and levels of living systems.

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Emergent Properties

Definition and complexity theory. Feeback between organism and environment. Need to study system as a whole with environmental influences. "Natural" state and man–made influences to our biosphere.

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Organism/Environment Interaction

Two–way relationship between the individual and the environment. Examples: Microbes and plants, nitrogen fixation, the carbon cycle, and fossil fuel.

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Molecular Ecology

Study of biosphere as a network of genes. Example: Ocean and microbial life.

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Primary Productivity

Collective photosynthesis. Types and habitats of primary photosynthesizers. Definitions and examples: Biomass, gross primary productivity, respiration rate, net primary productivity, mean residence time, and fractional turnover.

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World Net Productivity

Net primary productive and turnover time in different land and marine ecosystems.

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Food Web and Energy Transfers

Flow of energy through an organism within the food web. Comparisons of exploitation, assimilation, and production efficiencies of different organisms Connection and relationship between grazing, microbial, and detrivore food webs.

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Comparison of Ecosystems

Open ocean versus tropical forest ecosystems. Average ecological efficiency and number of tropic levels in each ecosystem.

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Terrestrial Ecosystems

Light, water, temperature correlate direct to productivity in terrestrial ecosystems.

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Biosynthesis and Regeneration

Conversion to organic forms, recycling, minerals and rocks. Comparison of tropical rain forests and temperate forests in terms of biomass and soil nutrient.

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Water Column

Light, temperature, and nutrients as functions of water depth. Light, water, and nutrients affect marine productivity. Nutrients are most dense in the bottom due to recycling.

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Lake Ecosystems and Mixing

Need to bring up nutrients from the bottom to the light at the top in order to utilize the nutrients. Thermocline in the lake and seasonal nutrient mixing.

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Ocean Nutrient Renewal

Definition and explanation of four types of mixing: Episodic mixing, costal upwelling, equatorial upwelling, and oceanic "conveyer belt".

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Importance of Nutrients

"Law of minimum." Growth of plants can be limited by nutrients in lowest supply relative to requirements. Example: Carbon/Nitrogen/Phosphorus ratio.

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Biogeochemical Cycles–Overview

Interconnected biogeochemical cycles. Definition of related terms. Flux, steady state and non–steady state effects. Solar energy as the primary source that drives the various cycles.

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Geological Cycle

Cycle participants and length. Solar and geothermal energies as input. Cycle includes various rocks and soils.

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Water Cycle

Reservoirs, fluxes, and balances within the cycle. Residence time of water in reservoirs.

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Global Phosphorous Cycle

Sedimentary cycle without atmospheric component. One way flow influenced by human activities. Reservoirs, fluxes, balances, and participants of the cycle.

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Global Nitrogen Cycle

Transformations between various nitrogenous components using redox chemistry–nitrification, denitrification, nitrogen fixation, and ammonification. Reservoirs, fluxes, imbalanced cycle, and human influences.

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Global Carbon Cycle

Reservoirs, fluxes, and imbalances that result in carbon dioxide annual increase in the atmosphere.

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Community Ecology

Definition, characteristics, and effects on the environment.

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Species Interactions

Definition and implications of Darwinian fitness, Adaptation, and Competition. Possible relationships between two organisms with respect to fitness.

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Competition

Intraspecific and interspecific competition.

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Ecological Niche

Definition, niche overlap, and competition.

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Competition Experiment

Gause's experiment of growing competing organisms in simple, controlled environment. Developed logistic equations to predict growth of one population taken into consideration size of the other population.

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Invasive Species and Competitive Exclusion

Case study of introduction of zebra mussel as an invasive species. Case study on growth of two species of barnacles.

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Biogeochemistry

Definition, scale, and studies. Earth as a biosphere.

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System for Bacteria

Environment and conditions of deep sea volcano for chemosynthetic bacteria.

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Character Displacement

Changes in physical characteristics that lead to competitive co–existence. Example: Beak depth of species on the same island.

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Evolution–Interspecific Competition

Growth, changes, and immigration of species inhabiting different islands.

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Predation

Predation as a force of evolution. Prey and predator logistic equations that are dependent on each other's densities, creating an oscillatory system. Example: Snowshoe hare and cats; prey and predator mites.

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Predation and Community Structure

John Wart's experiment that demonstrated that predation affects community structure within a niche. Predators and prey that drive evolution of both populations. Example: Industrial melanism.

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Productivity

Definition and calculation for primary productivity, gross and net productivity, mean residence time, and fractional turnover.

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Food Web–Definitions and Formulas

Definition and calculation for exploitation, assimilation, and production efficiencies at each trophic level and overall ecological efficiency.

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Ecosystems

Use characteristics and genes expressed in two ecotypes to determine their environment in the water.

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Food Web–Example

Productivities and efficiencies in a food web. Determine the food source that gives the highest ecological efficiency.

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Food Web–Energy Flow and Efficiencies

Components and energy transfer of a food web involving plants, herbivores, and carnivores. Example of estimated transfers and efficiencies.

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Communities

Example demonstrating predator–prey relationship as well as food source and consumption. Comparison of top–down and bottom–up models.

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Food Web–Introduction of New Trophic Level

Efficiencies and energy transfers in a food web. Changes in parameters created by addition of new organisms.

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Interspecific Interaction

Niche for individual species and relationships between two species.

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