- abiotic
 - nonliving components of the environment
 
- aboveground biomass
 - total mass of aboveground living plants per area
 
- abyssal zone
 - deepest part of the ocean at depths of 4000 m or greater
 
- algal bloom
 - rapid increase of algae in an aquatic system
 
- aphotic zone
 - part of the ocean where no light penetrates
 
- benthic realm
 - (also, benthic zone) part of the ocean that extends along the ocean bottom from the shoreline to the deepest parts of the ocean floor
 
- biogeography
 - study of the geographic distribution of living things and the abiotic factors that affect their distribution
 
- biome
 - ecological community of plants, animals, and other organisms that is adapted to a characteristic set of environmental conditions
 
- biotic
 - living components of the environment
 
- canopy
 - branches and foliage of trees that form a layer of overhead coverage in a forest
 
- channel
 - width of a river or stream from one bank to the other bank
 
- clathrates
 - frozen chunks of ice and methane found at the bottom of the ocean
 
- climate
 - long-term, predictable atmospheric conditions present in a specific area
 
- conspecifics
 - individuals that are members of the same species
 
- coral reef
 - ocean ridges formed by marine invertebrates living in warm, shallow waters within the photic zone
 
- cryptofauna
 - invertebrates found within the calcium carbonate substrate of coral reefs
 
- ecology
 - study of interaction between living things and their environment
 
- ecosystem services
 - human benefits and services provided by natural ecosystems
 
- emergent vegetation
 - wetland plants that are rooted in the soil but have portions of leaves, stems, and flowers extending above the water’s surface
 
- endemic
 - species found only in a specific geographic area that is usually restricted in size
 
- estuary
 - biomes where a source of fresh water, such as a river, meets the ocean
 
- fall and spring turnover
 - seasonal process that recycles nutrients and oxygen from the bottom of a freshwater ecosystem to the top
 
- global climate change
 - altered global weather patterns, including a worldwide increase in temperature, due largely to rising levels of atmospheric carbon dioxide
 
- greenhouse effect
 - warming of Earth due to carbon dioxide and other greenhouse gases in the atmosphere
 
- greenhouse gases
 - atmospheric gases such as carbon dioxide and methane that absorb and emit radiation, thus trapping heat in Earth’s atmosphere
 
- haze-effect cooling
 - effect of the gases and solids from a volcanic eruption on global climate
 
- heterospecifics
 - individuals that are members of different species
 
- intertidal zone
 - part of the ocean that is closest to land; parts extend above the water at low tide
 
- Milankovitch cycles
 - cyclic changes in the Earth's orbit that may affect climate
 
- neritic zone
 - part of the ocean that extends from low tide to the edge of the continental shelf
 
- net primary productivity
 - measurement of the energy accumulation within an ecosystem, calculated as the total amount of carbon fixed per year minus the amount that is oxidized during cellular respiration
 
- ocean upwelling
 - rising of deep ocean waters that occurs when prevailing winds blow along surface waters near a coastline
 
- oceanic zone
 - part of the ocean that begins offshore where the water measures 200 m deep or deeper
 
- pelagic realm
 - (also, pelagic zone) open ocean waters that are not close to the bottom or near the shore
 
- permafrost
 - perennially frozen portion of the Arctic tundra soil
 
- photic zone
 - portion of the ocean that light can penetrate
 
- planktivore
 - animal species that eats plankton
 
- predator
 - animal species that hunt and are carnivores or “flesh eaters”
 
- Sargassum
 - type of free-floating marine seaweed
 
- solar intensity
 - amount of solar power energy the sun emits in a given amount of time
 
- source water
 - point of origin of a river or stream
 
- thermocline
 - layer of water with a temperature that is significantly different from that of the surrounding layers
 
- weather
 - conditions of the atmosphere during a short period of time