AP Environmental Science: Biomes and Ecosystems Overview

biome

Grouping including land ecosystems which are alike in structure and climate.

permafrost

Layer of permanently frozen soil in cold climates.

epiphyte

Term for plant which roots on other plants but does not parasitize them.

ephemeral

Plant which completes its life cycle in an extremely short time.

succulents

Plant which stores water.

tropical rainforests

Biome with the highest rainfall.

desert

Biome with the lowest rainfall.

tundra

Biome characterized by low precipitation and low temperatures.

temperate grasslands

Biome with the richest soil and most suitable for farming.

savannahs

Biome with seasonal droughts located beside tropical rainforests.

temperate/deciduous forest

Biome with trees which change color in the fall.

boreal forest/taiga

Biome characterized by coniferous trees.

tropical rainforest/coral reef

Biome with the highest species diversity.

temperature

One of the two most important factors in determining a biome.

precipitation

One of the two most important factors in determining a biome.

alpine

Means mountainous when placed in front of the name of a biome.

pond

Aquatic biome that is smaller and shallower than a lake.

lake

Aquatic biome that is deeper and larger than a pond.

sunlight

One of the most important factors determining the characteristics of an aquatic biome.

oxygen

One of the most important factors determining the characteristics of an aquatic biome.

nutrients

One of the most important factors determining the characteristics of an aquatic biome.

freshwater biomes

The four major types are ponds, lakes, streams, and rivers.

3%

Percentage of the water on earth that is freshwater.

estuary

Bodies of water where rivers meet seas, important as breeding grounds for many ocean animals.

hydrologic cycle

Includes the three major processes: evaporation, condensation, and precipitation.

evapotranspiration

The sum of all processes by which water moves from the land surface to the atmosphere via evaporation and transpiration.

carbon dioxide

Removed from the atmosphere by photosynthesis.

global warming

The rising temperatures worldwide due to climate change.

legumes

Important in nitrogen fixation due to bacteria in nodules on their roots.

nitrifying bacteria

Convert ammonia to ammonium nitrate.

nitrogen-fixing bacteria

Convert atmospheric nitrogen to fixed nitrogen (ammonia).

denitrifying bacteria

Convert nitrates back to atmospheric nitrogen.

ammonifying bacteria

Decompose organic nitrogen from dead organisms and release inorganic nitrogen (ammonia) into the ecosystem.

phosphorus

The original source is rocks.

sulfur

Major source added to the atmosphere by humans.

Biotic

Factors in the environment that are alive

Abiotic

Factors in the environment that are nonliving

Autotroph

Scientific term for producer

Heterotroph

Scientific term for consumer

Scavengers

Animal which feeds on the remains of prey other animals have killed

Detritivores

Small animals which feed on ground litter

Saprophytes

Plant which grows on dead things

Decomposers

Organism which breaks down dead material into basic nutrients

Trophic levels

Feeding levels on an energy or biomass pyramid

Primary consumer

Consumer which eats producers

Secondary consumer

Consumer which eats herbivores

Tertiary consumer

Consumer which eats carnivores

Gross primary productivity

Amount of energy captured by an ecosystem

Net primary productivity

Amount of energy which can be passed to consumers

Energy transfer efficiency

The average percent of energy contained in an organism that can be passed to the next level in an ecosystem - 10%

Sunlight usage by plants

1-2%

What happens to the energy which is lost at each level?

dissipated as heat

chain is one flow of energy, web is multiple

What is the difference in a food chain and a food web?

Equation for GPP

GPP = NPP + Respiration, NPP = GPP-Respiration

Because it is the sum of NPP and respiration

Why can GPP not be measured directly?

What are the units for GPP?

kilograms*jules/per some area/per some time period

What is the usual NPP (as a percent of GPP) for an ecosystem?

40%

What two land ecosystems have the highest NPP?

swamps and marches

What two marine ecosystems have the highest NPP?

tropical rainforests and temperate rainforests

What is meant by provisioning?

produce something

What is meant by regulating?

regulate something

What is meant by supporting?

support an ecosystem (nutrient cycles, oxygen production)

What is meant by cultural?

for the benefit of humans

What is meant by species biodiversity?

variety of all living things

What is meant by genetic biodiversity?

variety of genes in a population of a species

What is meant by ecosystem biodiversity?

variety of habitats, communities, etc

What is meant by species richness?

number of different species

What is meant by species evenness?

even distribution of abundance of species

What is the Simpson Biodiversity Index?

measure of diversity

Who originated the theory of Island Biogeography and what two factors determine the biodiversity of an island?

EO Wilson size/distance from mainland

What are habitat corridors and how are they used?

narrow strips of land that differ from surrounding habitat—allow animals to cross b/t one area to another

Generalist vs Specialist

Distinguish between a generalist and a specialist and know under what conditions each one does well.

What are meant by periodic, episodic and random disturbances?

Periodic: occurs at regular intervals, Episodic: Occurs at irregular intervals, Random: No predictability

What are the two main reasons for animal migration?

seasons (which makes the food and climate for them) reproduction (ex: whales, birds, butterflies)

When did Darwin publish his theory of natural selection?

1858

What work allowed him to develop his theory?

being a naturalist on a ship (aka the beagle)

What animal did he study in the Galapagos that was critical to his theory?

finches

mass extinctions

5

sixth mass extinction reason

anthropogenic/human

Pioneer species

first species to come back after succession

Keystone species

the rest of the ecosystem relies on them

Indicator species

present in one stage

stages of primary succession

lichen/moss, grasses, shrubs, shade intolerant, shade tolerant

primary succession

occurs on barren rock

secondary succession

occurs after a community is destroyed

Distribution (dispersal)

spatial arrangement of organisms within a particular area.

Carrying capacity

maximum population of a particular species that a given habitat can support over a given period

Intrinsic growth rate (biotic potential)

maximum reproductive rate of an organism, given unlimited resources and ideal environmental conditions

Population density

the number of individuals per unit area at a given time

Exponential growth

rapid and continuous increase in population size over time, where the growth rate is proportional to the current population

Logistic growth

rapid exponential population growth, followed by a steady decrease in population growth until the population size levels off

Overshoot

population of a species exceeds the carrying capacity of its environment, leading to negative consequences such as resource depletion and environmental degradation

Fertility rate

number of children a woman in a population will bear throughout her lifetime

Replacement rate

total fertility rate needed for a population to replace itself without any increase or decrease

DTM

Stages of population structure a nation undergoes while adjusting to industrialization

Uniform distribution

even distribution, territory

Random distribution

random spacing, resources are throughout an area or organisms do not influence where a population settles

Clumped distribution

clusters, around resources

density dependent factors

rely on density (disease)

density independent factors

does not rely on density (fires, earthquakes)