freshwater sponge
41inland water ecosystem — ▪ biology Introduction complex of living organisms in free water on continental landmasses. Inland waters represent parts of the biosphere within which marked biological diversity, complex biogeochemical pathways, and an array of… …
42Algal bloom — Algal blooms can present problems for ecosystems and human society An algal bloom is a rapid increase or accumulation in the population of algae (typically microscopic) in an aquatic system. Algal blooms may occur in freshwater as well as marine… …
43Eutrophication — The eutrophication of the Potomac River is evident from its bright green water, caused by a dense bloom of cyanobacteria. Eutrophication (Greek: eutrophia healthy, adequate nutrition, development; German: Eutrophie) or more precisely… …
44Zebra mussel — Live zebra mussels underwater with shells open, animals respiring, siphons visible. Scientific classification Kingdom …
45River delta — Nile River delta, as seen from Earth orbit. The Nile is an example of a wave dominated delta that has the classic Greek delta (Δ) shape after which river deltas were named. A delta is a landform that is formed at the mouth of a river where that… …
46Everglades National Park — IUCN Category Ib (Wilderness Area) …
47Marine aquarium — See also: Reef aquarium A marine aquarium …
48Hypoxia (environmental) — Hypoxia, or oxygen depletion, is a phenomenon that occurs in aquatic environments as dissolved oxygen (DO; molecular oxygen dissolved in the water) becomes reduced in concentration to a point where it becomes detrimental to aquatic organisms… …
49Spawn (biology) — The spawn (eggs) of a clownfish. The black spots are the eyes developing. Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm,… …
50Coastal fish — Schooling threadfin, a coastal species Coastal fish, also called offshore fish or neritic fish, are fish that inhabit the sea between the shoreline and the edge of the continental shelf. Since the continental shelf is usually less than 200 metres …
