APES Unit 1: The Living World: Ecosystems

Individual

One organism (living thing)

Population

Group of individuals of the same species

Community

All living things in an area

Ecosystem

All living and non-living things in an area

Biome

Area that shares combination of average yearly temperature (climate) and precipitation. Determines plant and animal species habitat.

Competition

Organisms fighting over resources

• Limits population sizes from not enough resources

Predation

One organism using another for energy

• Benefits A, Harms B

Mutualism

Type of Symbiosis: Relationship that benefits both organism

• Benefits A and B

Ex. coral reef and algae

Commensalism

Type of Symbiosis: Relationship that benefits one organism, other unaffected

• Benefits A, B = 0

Parasitism

Type of Symbiosis: Relationship that benefits one organism, other harmed

• Benefits A, Harms B

Symbiosis

Any close and long-term interaction between 2 organisms of different species Not necessarily good relationships.

• Mutualism

• Commensalism

• Parasitism

Parasite

Uses host organism for energy, WITHOUT directly killing it. Organism that benefits from Parasitism.

Parasitoid

Specific type of Parasite. Lays eggs inside host, which hach and then eat the host.

Competition

Interaction between organism / species that reduces population size. As resources resource, the amount of organisms that survive also decrease.

• Intraspecific: same species.

  • Mating competition

• Interspecific: different species

  • Food, Habitat, Etc. Competition

Resource Partioning

Solution to Interspecific Competition: different species using the same resource in different ways.

• Temporal Partitioning: resources used at different times

• Spatial Partitioning: different areas occupied of a shared habitat

• Morphological Partitioning: different resources used based on different evolved body features

Biome Characteristics (Terrestrial)

Defined by annual temperature + average precipitation

• Tundra + Boreal: Higher (60) latitudes: low precipitation, low temperature

  • Poor soil- temperature too low, decomposition is not fast enough. Acidic and thin soil.

• Temperate: Mid (30-60) latitudes

  • Grassland, Cold Desert, Seasonal Forest, Rainforest

    • Rich soil: deciduous leaves from trees give ground nutrients. Faster decomposition with temperature.

• Tropical: Lower (30) latitudes

  • Rainforest, Seasonal Forest, Savanna

  • Poor soil: too many plants in competition, nutrients absorbed too quickly.

Latitude determines climate.

Biomes shift with climate change.

Biome Characteristics (Aquatic)

Salinity

• How much salt in body of water which species can survive. Usability for drinking

Depth

• Influences how much sunlight reaches plants below surface for photosynthesis

Flow

• How much O2 can dissolve in water

  • Rivers/Streams/Rapid Moving Water have more O2

• Determines which organisms survive

Temperature

• Hotter temperature, less dissolved O2. Supports less aquatic organisms.

  • Rivers/Streams/Rapid Moving Water is Colder

Rivers and Lakes

Freshwater Biome

Rivers: high O2 and niutrient rich sediments, fertile.

Lakes: standing bodies of water. Key drinking water source.

• Littoral Zone: shallow water with emergent plants (reeds, cattails —> adapted to need less oxygen underwater)

• Limnetic Zone: where light reaches for photosynthesis

• Profundal Zone: where light does not reach

• Benthic Zone: murky bottom of water. Habitat for invertebrates. Nutrient-rich organic sediments

Wetlands

Freshwater Biome

Area with soil submerged/saturated in water for at least part of the year. Shallow enough for emergent plants (reeds, cattails. peek out of water with roots in soil).

→ Stores excess water during storms. —> Less floods.

→ Refills squifers by absorbing rainfall in soil.

→ Filters pollutants through plant roots.

→ High plant growth. Water & organic sediments, nutrients

• Swamps (cyprus tres (coniferous))

• Marshes (reeds, cattails)

• Bogs (spruce, sphagnum moss)

Estuaries

Freshwater and Saltwater Biome

Areas where rivers empty into ocean

High productivity (high nutrients come from river)

• Salt Marsh

  • Along temperate climate coasts

  • Breeding grounds for (shell)fish species.

• Mangrove Swamps

  • Along tropical climate coasts.

  • Mangrove trees: stilted roots. Stabilize soil. Habitat for fish. Storm protection.

Coral Reefs

Saltwater Biome

Warm, shallow waters beyond shoreline.

Most diverse marine biome. Has a mutualistic relationship with Algae.

• Coral —> receives Co2 for calcium carbonate exoskeleton

• Algae —> gives reef sugar in exchange for Co2

Intertidal Zone

Saltwater Biome

Narrow coastline between high and low tide

—> Organisms are adapted to withstand waves, sunlght, and heat

• Barnacles, sea stars, rock-attached crabs

  • Prevents desiccation (drying out) through tough outer layers

Open Ocean

Saltwater Biome

Low productivity (too deep). Only has algae and phytoplankton.

• Produces large amounts of oxygen for planet AND Absorbs atmospheric Co2

  • Photic Zone: area where sunlight and photosynthesis occurs

  • Aphotic Zone: area that is too deep for sunlight

    • Has bioluminescent organisms, adapted for high pressure environment.

Carbon Cycle

Movement of molecules that contain carbon (Co2, methane, glucose) between sources/sinks

Carbon source: processes that ADD carbon to atmosphere

• Fossil fuel combustion (oil, coal, natural gas)

• Animal agriculture (methane)

• Deforestation

Carbon sink: reservoirs that STORE carbon

• Oceans

• Forests

Photosynthesis / Cellular Respiration

Photosynthesis: process that removes Co2 from atmosphere. Becomes glucose. —> Cycles between biosphere & atmosphere

• Carbon sink; plants only

Cellular Respiration: process that releases Co2 into atmosphere. Takes in oxygen.

• Carbon source; all living things

Short-term cycle. Balance- no net gain/loss of atmospheric carbon.

Nitrogen Cycle

Movement of nitrogen into atmosphere. Nitrogen held for shorter amount of time in sinks compared to Carbon.

—> Plants, soil, atmosphere hold 78%

Most Nitrogen is N2 gas (unuseable to plants/animals).

Key limiting nutrient. Needed for DNA, amino acids

Nitrogen Fixation

Process of N2 gas converted into biologically available ammonia or nitrate. ‘Fixes’ nitrogen for usage.

• Bacterial Fixation: certain bacteria that live in soil that fixes nitrogen. Symbiotic relationship with plant root nodules (legumes) to make amino acids.

  • N2 → AMMONIA.

• Synthetic Fixation: humans combust fossil fuels.

  • N2 → NITRATE (added to fertilizer)

Assimilation

Plants (NITRATE) and Animals (AMMONIA) use nitrogen to create DNA or use nitrogen as energy from eating other plants/animals.

Ammonification

Process of dead biomass converting into ammonia.

Done by:

• Soil Bacteria

• Microbes

• Decomposers

• Nitrogen-Fixing Bacteria

Nitrification

Process of ammonium converting into nitrate and nitrogen dioxide.

Done by soil bacteria.

Denitrification

Process of nitrate in soil converting into nitrous oxide.

Biosphere (soil) → Atmosphere