The Living World: Ecosystems

Salinity

The saltiness or amount of salt dissolved in a body of water.

Phytoplankton

The autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems.

Littoral Zone

The part of a sea, lake, or river that is close to the shore.

Limnetic Zone

The open and well-lit area of a freestanding body of fresh water, such as a lake or pond.

Profundal Zone

The deep zone of a lake, located below the range of effective light penetration.

Benthic Zone

The ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers.

Intertidal Zone

The area above water level at low tide and underwater at high tide.

Temperate Rainforest

Rainforests with coniferous or broadleaf forests that occur in the temperate zone and receive heavy rain.

Hydrologic Cycle

A biogeochemical cycle that involves the continuous movement of water on, above and below the surface of the Earth across different reservoirs.

Surface Water

Water located on top of land, forming terrestrial (surrounding by land on all sides) waterbodies.

Oligotrophic

Lakes with a low level of productivity.

Mesotrophic

Lakes with an intermediate level of productivity.

Eutrophic

Lakes with a high level of productivity.

Climate

The long-term weather pattern in a region.

Temperate Grasslands

The predominant vegetation in these biomes consists of grass and/or shrubs. The climate is temperate and ranges from semi-arid to semi-humid.

Savanna

A mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterized by the trees being sufficiently widely spaced so that the canopy does not close.

Chaparral

A shrubland plant community found primarily in California, southern Oregon, and northern Baja California.

Desert

A landscape where little precipitation occurs.

Eutrophication

A process in which nutrients accumulate in a body of water, resulting in an increased growth of organisms that may deplete the oxygen in the water.

Thermal Stratification

The tendency of lakes to form separate and distinct thermal layers during warm weather.

Fall turnover

The seasonal mixing of a lake.

Swamp

A forested wetland.

Marsh

A wetland that is dominated by herbaceous plants rather than by woody plants.

Wetland

A distinct semi-aquatic ecosystem whose groundcovers are flooded or saturated in water.

Estuary

A partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea.

Tropical Rain Forest

Dense and warm rainforests with high rainfall typically found between 10° north and south of the Equator.

Temperate Deciduous Forest

A variety of temperate forest dominated by deciduous trees that lose their leaves each winter.

Temperature

Quantitatively expresses the attribute of hotness or coldness.

Precipitation

Any product of the condensation of atmospheric water vapor that falls from clouds due to gravitational pull.

Latitude

A geographic coordinate that specifies the north-south position of a point on the surface of the Earth.

Biome

A distinct geographical region with specific climate, vegetation, and animal life.

Tundra

A type of biome where tree growth is hindered by frigid temperatures and short growing seasons.

Permafrost

Soil or underwater sediment which continuously remains below 0 °C (32 °F) for two years or more.

Boreal Forest/Conifer Forest/Taiga

A biome characterized by coniferous forests consisting mostly of pines, spruces, and larches.

Figures/ Equations to Know

NPP = GPP - RL

10% of all energy moves from one trophic level to the next