Ecology - Science Olympiad notes

What is a food web?

A food web consists of all the food chains in a single ecosystem.

What does the trophic pyramid illustrate?

The trophic pyramid illustrates energy transfer within ecosystems, highlighting primary producers, consumers, and decomposers.

What is the percentage of energy transferred between trophic levels in an ecosystem?

Only 10% of energy is transferred between trophic levels.

What is Gross Primary Productivity (GPP)?

GPP is the rate at which the primary producers capture and store energy per unit time.

What is Net Primary Productivity (NPP)?

NPP is the amount of energy stored after accounting for energy expended during respiration; calculated as NPP = GPP - R.

What are density dependent limiting factors?

Factors that depend on the population size, including disease, pollution, competition, and predation.

What are density-independent factors?

Factors that affect population regardless of its size, such as climate extremes and food limitations.

What does carrying capacity refer to?

The number of individuals that the environment can support over a long period of time.

How is doubling time calculated?

Doubling time = 70 / r, where r is the growth rate in percent.

What is logistic growth?

When a population's growth rate decreases as the population size approaches the carrying capacity.

What is R-selection?

A reproductive strategy characterized by producing many offspring with low parental investment.

What is K-selection?

A reproductive strategy characterized by fewer offspring with heavy parental investment.

What is adaptive radiation?

The diversification of a group of organisms into forms filling different ecological niches.

What do survivorship curves show?

Patterns of mortality and the probability that members of a population will survive to a certain age.

What is trophic mutualism?

The transfer of energy and nutrients between two species, often between an autotroph and a heterotroph.

What characterizes the tundra biome?

Cold, largely treeless with permafrost and a short growing season.

What type of trees dominate the taiga biome?

Coniferous trees such as pines, firs, and spruces.

What is unique about deciduous forests?

They have trees that lose their leaves at the end of the growing season.

How does biodiversity benefit ecosystems?

It provides services such as clean air, freshwater, and act as a barrier to zoonotic diseases.

What is acid rain?

Precipitation with acidic components that fall to the ground from the atmosphere.

What are invasive species?

Non-native organisms that cause economic or environmental harm.

What impact does soil erosion have?

It reduces land productivity by causing loss of water, nutrients, and organic matter.

What is the difference between alternative energy and renewable energy?

Alternative energy does not come from fossil fuels and produces little or no greenhouse gases; renewable energy is naturally replenished.

What is conservation biology?

A science aimed at evaluating human impacts on biological diversity and developing strategies to prevent species extinction.

What is primary succession?

The process that occurs in a landscape that previously was devoid of life.

What is species reintroduction?

The process of re-establishing a population in an area where it has previously been driven out.

What is inquilinism?

A relationship where an animal lives commensally in another animal's nest or dwelling.

What does biotic potential refer to?

The maximum rate of population growth under ideal conditions.

What is metabolic recycling of nutrients?

The process by which decomposers break down organic matter, facilitating the nutrient cycle.