| A | B |
|---|
| evaporation | changing from a liquid to a gas; occurs only at the surface |
| freezing | changing from liquid to solid |
| melting | changing from solid to liquid |
| 100 degrees Celsius | normal boiling point of water |
| 0 degrees Celsius | normal freezing point of water |
| sublimation | changing directly from a solid to a gas |
| condensation | changing from a gas to a liquid |
| channel | path that a stream or river follows |
| water cycle | process by which water moves from Earth, through the atmosphere, and back to Earth |
| divide | area of higher ground between watersheds |
| tributary | stream that flows into a river |
| erosion | process by which soil and sediment are transported |
| load | particles and sediments that are carried by a river |
| watershed | area of land drained by a river |
| sewage treatment plant | place where waste is cleaned from water |
| nitrates | nitrongen compounds that can affect water quality |
| alkalinity | measure of basicity |
| dissolved oxygen | element whose concentration decreases as water pollution increases |
| nonpoint source | pollution that comes from more than one place and is hard to identify |
| point source | pollution that comes from an identifiable place |
| aquifer | underground pools of water |
| turbididty | measure of concentration of suspended particles |
| biological indicators | living signs of water quality |
| transpiration | loss of water through plant leaves |
| infiltration | movement of water into the ground |
| runoff | precipitation that does not filter into the ground and flows across the land |
| salinity | concentration of dissolved solids in a given amount of liquid |
| thermocline | area of ocean with most dramatic temperature change as depth increases |
| plankton | organisms that float or drift near the surface |
| phytoplankton | produce own food through photosynthesis |
| zooplankton | consumers |
| nekton | organisms that swim actively in opean ocean |
| benthos | live on the ocean floor |
| intertidal zone | near shore and is exposed for part of the day |
| neritic zone | area where ocean floor starts to slope, water is deeper, plenty of sunlight |
| oceanic zone | deep water of open ocean |
| benthic zone | ocean floor; deepest parts don't receive any light |
| continental slope | steeply inclined section of the continental margin |
| continental shelf | gently sloping section of the continental margin near the shore |
| continental rise | gently sloping area of sediments near the ocean floor |
| abyssal plain | flat portion of the ocean floor |
| mid-ocean ridges | chains of mountains on ocean floor |
| seamounts | underwater volcanoes |
| trench | deep crack in ocean floor |
| rift valley | area between mid-ocean ridges where magma rises |
