a warm-blooded vertebrate with feathers, wings, and a beak whose young are born from eggs
bird
the height of an area of land above sea level
elevation
a compound made of hydrogen and oxygen
water
relating to water
aquatic
water that is not fresh; water that has things dissolved in it that make it taste salty
salt water
flow of water (as from a stream, river or pipe)
discharge
water that is not salty, such as that found in streams and lakes
freshwater
a coastal body of water where fresh water from a river mixes with salt water from the ocean
estuary
a fan-shaped mass of mud and other sediment that forms where a river enters a large body of water
delta
the flat part of a river valley consisting of sediment deposited by the river
floodplain
an area of land where there is water on the surface or where the soil is completely filled with water for at least part of the year
wetland
an element or compound that an organism must consume or synthesize in order to survive
nutrients
water stored below Earth's surface in soil and rock layers
groundwater
When soil is moved from one location to another by wind or water.
erosion
the introduction of any harmful substance or form of energy into the environment at a faster rate than it can be cleansed
pollution
resources that are obtained from the earth
natural resources
water that is released from clouds in the sky; includes rain, snow, sleet, hail, and freezing rain
precipitation
the study of all natural and political features of Earth's surface
geography
a low, flat area of land that borders the ocean
coastal plain
a major ecological community such as grassland, tropical rain forest, or desert
biome
undesirable or harmful substance that alters the natural balance of an ecosystem, particularly found in air, soil, or water
pollutant
the average weather conditions in an area
climate
solid material, moved by wind, water, and other forces, that settles on the surface of land or the bottom of a body of water
sediment
the location in which an organism lives
habitat
plant-like organisms in kingdom Protista; many are single-celled
algae
a small body of flowing water
stream
the continual movement of water between the land, ocean, and the air
water cycle
the presence of many different types of organisms in an ecosystem
biological diversity
a large natural structure on the earth's surface such as a mountain, a plain, or a valley
landform
large body of water flowing through land on either side
river
all the living and nonliving things that surround an organism
environment
winding or indirect movement or course
meander
tree that grows in tidal zones
mangrove