Studied by 81 people
Climate
The average weather that occurs in a given region over a long period of time.
Weather
The short-term conditions of the atmosphere in a local area that include temperature, humidity, clouds, precipitation, and wind speed.
Community ecology
The study of interactions among species.
Symbiosis
Two species living in a close and long-term association with one another in an ecosystem.
Biosphere
The region of our planet where life resides.
Competition
The struggle of individuals, either within or between species, to obtain a shared limiting resource.
Competitive exclusion principle
The principle stating that two species competing for the same limiting resource cannot coexist.
Resource partitioning
When two species evolve to divide a resource based on differences in their behavior or morphology.
Predation
An interaction in which one animal typically kills and consumes another animal.
Parasitoid
A specialized type of predator that lays eggs inside other organisms — referred to as its host.
Parasitism
An interaction in which one organism lives on or in another organism, referred to as the host.
Pathogen
A parasite that causes disease in its host.
Herbivory
An interaction in which an animal consumes plants or algae.
Mutualism
An interaction between two species that increases the chances of survival or reproduction for both species.
Photosynthesis
The process by which plants and algae use solar energy to convert carbon dioxide and water into glucose and oxygen .
Commensalism
An interaction between two species in which one species benefits and the other species is neither harmed nor helped.
Native species
A species that lives in its historical range, typically where it has lived for thousands or millions of years.
Invasive species
A species that spreads rapidly across large areas and causes harm.
Biome
The plants and animals that are found in a particular region of the world.
Terrestrial biome
A geographic region of land categorized by a particular combination of average annual temperature, annual precipitation, and distinctive plant growth forms.
Aquatic biome
An aquatic region characterized by a particular combination of salinity, depth, and water flow.
Habitat
An area where a particular species lives in nature.
Tundra
A cold and treeless biome with low-growing vegetation.
Permafrost
An impermeable, permanently frozen layer of soil.
Taiga
A forest biome made up primarily of coniferous evergreen trees that can tolerate cold winters and short growing seasons. Also known as boreal forest.
Temperate rainforest
A coastal biome typified by moderate temperatures and high precipitation.
Temperate seasonal forest
A biome with warm summers and cold winters with over 1 m (39 inches) of annual precipitation.
Shrubland
A biome characterized by hot, dry summers and mild, rainy winters. Also known as woodland.
Temperate grassland
A biome characterized by cold, harsh winters, and hot, dry summers. Also known as cold desert.
Tropical rainforest
A warm and wet biome found between 20° N and 20°S of the equator, with little seasonal temperature variation and high precipitation.
Savanna
A biome marked by warm temperatures and distinct wet and dry seasons. Also known as tropical seasonal forest.
Hot desert
A biome located at roughly 30° N and 30° S, and characterized by hot temperatures, extremely dry conditions, and sparse vegetation.
Freshwater biomes
Categorized as streams and rivers, lakes and ponds, or freshwater wetlands.
Littoral zone
The shallow zone of soil and water in lakes and ponds near the shore where most algae and emergent plants such as cattails grow.
Limnetic zone
A zone of open water in lakes and ponds as deep as the sunlight can penetrate.
Phytoplankton
Floating algae.
Profundal zone
A region of water where sunlight does not reach, below the limnetic zone in very deep lakes.
Benthic zone
The muddy bottom of a lake, pond, or ocean beneath the limnetic and profundal zones
Oligotrophic
Describes a lake with a low level of phytoplankton due to low amounts of nutrients in the water.
Mesotrophic
Describes a lake with a moderate level of fertility.
Eutrophic
Describes a lake with a high level of fertility.
Freshwater wetland
An aquatic biome that is submerged or saturated by water for at least part of each year, but shallow enough to support emergent vegetation.
Estuary
An area along the coast where the fresh water of rivers mixes with salt water from the ocean.
Salt marsh
Found along the coast in temperate climates, a marsh containing nonwoody emergent vegetation.
Mangrove swamp
A swamp that occurs along tropical and subtropical coasts, and contains salt-tolerant trees with roots submerged in water.
Intertidal zone
The narrow band of coastline that exists between the levels of high tide and low tide.
Coral reef
Represents Earth’s most diverse marine biome, and are found in warm, shallow waters beyond the shoreline in tropical regions.
Coral bleaching
A phenomenon in which algae inside corals die, causing the corals to turn white.
Open ocean
Deep-ocean water, located away from the shoreline where sunlight can no longer reach the ocean bottom.
Photic zone
The upper layer of ocean water in the ocean that receives enough sunlight for photosynthesis.
Aphotic zone
The deeper layer of ocean water that lacks sufficient sunlight for photosynthesis.
Chemosynthesis
A process used by some bacteria to generate energy with methane and hydrogen sulfide.
Biogeochemical cycle
The movements of matter within and between ecosystems involving cycles of biological, geological, and chemical processes.
Reservoirs
The components of the biogeochemical cycle that contain the matter, including air, water, and organisms.
Carbon cycle
The movement of carbon around the biosphere among reservoir sources and sinks.
Photosynthesis and respiration, exchange and sedimentation and burial, extraction and combustion
Aerobic respiration
The process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.
Steady state
When a system’s inputs equal outputs, so that the system is not changing over time.
Greenhouse gases
Gases in Earth’s atmosphere that trap heat near the surface.
Global warming
The increase in global temperatures due to humans producing more greenhouse gases.
Limiting nutrient
A nutrient required for the growth of an organism but available in a lower quantity than other nutrients.
Nitrogen cycle
The movement of nitrogen around the biosphere among reservoir sources and sinks.
Nitrogen fixation, nitrification, assimilation, mineralization/ammonification, denitrification
Nitrogen fixation
The process that converts nitrogen gas in the atmosphere (N2) into forms of nitrogen that plants and algae can use.
Nitrification
The conversion of ammonium (NH4) into nitrite (NO2) and then into nitrate (NO3).
Assimilation
A process by which plants and algae incorporate nitrogen into their tissues.
Mineralization
The process by which fungal and bacterial decomposers break down the organic matter found in dead bodies and waste products and convert these organic compounds back into inorganic compounds, such as inorganic ammonium (NH4). Also known as ammonification.
Denitrification
The conversion of nitrate in a series of steps into the gases nitrous oxide and, eventually, nitrogen gas (N2), which is emitted into the atmosphere.
Anaerobic
An environment that lacks oxygen.
Aerobic
An environment with abundant oxygen.
Leaching
A process in which dissolved molecules are transported through the soil via groundwater.
Phosphorus cycle
The movement of phosphorus around the biosphere among reservoir sources and sinks.
Assimilation and Mineralization, sedimentation and geological uplift and weathering
Algal bloom
A rapid increase in the algal population of a waterway.
Hypoxic
Low in oxygen.
Dead zone
When oxygen concentrations become so low that it kills fish and other aquatic animals.
Hydrologic cycle
The movement of water around the biosphere among reservoir sources and sinks.
Transpiration
The release of water from leaves into the atmosphere during photosynthesis.
Evapotranspiration
The combined amount of evaporation and transpiration.
Producers
Plants, algae, and some bacteria that use the Sun’s energy to produce usable forms of energy, such as sugars. Also known as autotrophs.
Primary productivity
The rate of converting solar energy into organic compounds over a period of time.
Gross primary productivity (GPP)
The total amount of solar energy that producers in an ecosystem capture via photosynthesis over a given amount of time.
Net primary productivity (NPP)
The energy captured by producers in an ecosystem minus the energy producers respire.
Biomass
The total mass of all living matter in a specific area.
Standing crop
The amount of biomass present in an ecosystem at a particular time.
Amount of energy
Trophic levels
The successive levels of organisms consuming one another.
Detritivore
An organism that specializes in breaking down dead tissues and waste products into smaller particles.
Ecological efficiency
The proportion of consumed energy that can be passed from one trophic level to another.
The 10% rule
Of the total biomass available at a given trophic level, only about 10 percent can be converted into energy at the next higher trophic level.
Trophic pyramid
A representation of the distribution of biomass, numbers, or energy among trophic levels.
