| Algae | Single or multicelled organisms, usually found in surface water, which produce their own food through photosynthesis. |
| Algae bloom | An overgrowth of algae. |
| Anoxia | The total lack of dissolved oxygen in water. |
| Amoeba | A single-celled, shapeless, primitive form of animal life. |
| Benthic | Bottom dwelling. |
| Brown tide | A nontoxic overgrowth of algae that clouds the water and prevents sunlight from penetrating deeper waters. |
| Buffer | A strip of grass, trees or other plant material that is designed to remove sediments and nutrients from runoff water before it goes into a water body. |
| Chloroplast | the organelle in a plant cell that contains chlorophyll and is the site of photosynthesis. |
| Cyst | A capsule formed around a microbe as the organism goes into a resting or spore stage. |
| Diatoms | A class of algae characterized by silicified skeletons. |
| Dinoflagellate | Any of an order of chiefly marine planktonic microorganisms that can move themselves through the water with a taillike structure. Autotrophic dinoflagellates photosynthesize, using inorganic nutrients, while heterotrophic dinoflagellates must feed on organic material. |
| Ecosystem | Community of different species interacting with one another and their surroundings. |
| Estuary | Coastal area at the mouth of a river where its fresh water mixes with salt water from the marine environment. |
| Food web | complex network of feeding relationships in an ecosystem. |
| Hypoxia | A condition that occurs when water contains too little dissolved oxygen to support the requirements of the organisms that live there. |
| Membrane | A very thin layer of tissue. |
| Microbe | A microorganism. |
| Nitrate | (NO²-) a water-soluble form of nitrogen usable by plants when nitrites are unavailable. |
| Nitrite | (NO7-)the water-soluble form of nitrogen most usable by plants. |
| Nonpoint source pollution | Pollution that cannot be traced to a specific source. Often involves water washing pollution from a large section of land into a water body. |
| Nutrient | Any substance an organism must take in to live, grow or reproduce. |
| Nutrient enrichment | A condition that results when a water body receives more nutrients than the organisms within it need for normal life, growth and reproduction. |
| Phosphorus | An organic nutrient required by plants. Often found in fertilizers and detergents. |
| Photosynthesis | The formation of carbohydrates in the tissues of plants exposed to the sun. |
| Phytoplankton | Microscopic floating plant life like algae and certain seagrasses. |
| Red tide | An overgrowth of one of a number of dinoflagellates that causes discoloration of the water. Some organisms that cause red tides can release neurotoxins. |
| Riparian | Of or related to the bank of a stream or river. |
| Watershed | Land area that delivers the water, sediment and dissolved substances via small streams to a major stream. |
| Zooplankton | Microscopic floating animal life, including krill and the larvae of various animals. |
This glossary appeared in the special Fall issue of 1997 of Gulfwatch, a publication of the National Association of Conservation Districts in League City, TX. They can be reached at 281-422-3724 if you want to subscribe or need more info.