Biology II Unit 5 Chapter 46 Ecology of Ecosystems

Ecology

Study of interactions between organisms and their environment, with particular interest in the competition for resources

Natural disturbances

Fire, rainfall, drought

Unnatural disturbances

Anthropogenic (human caused), like deforestation, pollution, burning fossil fuels

Ecosystem resistance

The ecosystem's ability to REMAIN in equilibrium despite a disturbance

Ecosystem resilience

The ecosystem's speed of RECOVERY after a disturbance

Ecosystem dynamics

Studies the changes in ecosystems due to disturbances, using models

Holistic ecosystem model

Quantifies the competition, interactions, and dynamics of an ecosystem. Most accurate, but expensive and time-consuming

Mesocosm model

Partitions off part of the ecosystem, which is good for in-situ study but changes the dynamics by partitioning organisms

Mircocosm model

Recreates ecosystem, which makes it very easy to study, but removing the organisms changes the dynamic

Conceptual modeling

Uses flow charts to show interactions between organisms and between them and the environment

Analytical modeling

Uses mathematical formulas to predict how ecosystem will respond to disturbances

Simulation modeling

Uses complex computer algorithms to model ecosystems and make predictions

AI

More robust, heavy duty simulations and analytics, able to do a lot of the brunt work and predictions

Is any model perfectly correct?

No, all models are missing something

Food chain

Linear sequence of energy moveemnt through organisms (one path)

Food chain trophic level progession

Primary producer -> primary consumer -> secondary consumer -> tertiary consumer

What happens to energy as you move up through trophic levels?

Energy is lost at each level as heat, so each higher trophic level has less and less energy

Food web

Web of consumers/producers, most accurate model

Grazing food web

Starts with photosynthetic organisms at the base

Detrital food web

Has decomposers at the base

Where do omnivores go on the trophic levels?

They can be primary consumers or secondary consumers, depending on which food source they are focusing on

Ecosystem productivity

The percent of energy entering the ecosystem as biomass at each trophic level

Biomass

The measurement of living and previously living organisms within a trophic level

Gross primary product

The amount of energy primary producers bring into the ecosystem

Net primary productivity

The amount of energy available to the next trophic level, after accounting for the energy requirements of the current level

Bioaccumulation

Increasing concentration of toxic substances in organisms at each trophic level

How much of Earth's water is useable freshwater?

1% of the 2.5% of water on earth that is fresh water is readily available for use

Hydrologic cycle

Evaporation or sublimation caused by sun warming the surface, bringing water vapor into the atmosphere. Here it condenses and falls back to the ground as precipitation. Here it will either evaporate again, or seep into the ground where it will eventually reach the surface again.

How is the hydrologic cycle important?

Rain and surface runoff cycle minearls from land to the water, and the cycle itself cycles water to all organisms

Carbon cycle through organisms

Autotrophs use carbon dioxide to build glucose, producing oxygen waste. Heterotrophs consume oxygen and exhale carbon dioxide, used by autotrophs.

Heterotrophs also consume autotrophs, transferring their carbon content.

Carbon cycle through geologic processes

Atmosphere and ocean exchange CO2. The ocean dissolves CO2, forming carbonic acid. On land, deocomposing organisms and weathering rocks deposits carbon in soil, which is carreid by runoff.

How does carbon on land enter the atmosphere naturally?

Volcanic eruption, cellular respiration

How does carbon on land enter the atmosphere unnaturally?

Burning fossil fuels

Human impact

Humans use a lot of carbon, which goes into the atmosphere, which has a lot of adverse affects. This is through fossil fuel useage and farming mass amounts of animals.