Aquaculture & Fisheries

Aquatic ecology

Aquatic ecology includes the study of these relationships in all aquatic environments, including oceans, estuaries, lakes, ponds, wetlands, rivers, and streams. An ecosystem is a community of living organisms and their physical and chemical environment, linked by flows of energy and nutrients. Aquatic ecosystems perform many important environmental functions. For example, they recycle nutrients, purify water, attenuate floods, recharge ground water and provide habitats for wildlife. Physical alterations include changes in water temperature, water flow and light availability.

Aquatic ecosystems include oceans, lakes, rivers, streams, estuaries, and wetlands. Aquatic organisms generally fall into three broad groups: plankton, nekton, and benthos. They vary in how they move and where they live. Plankton are tiny aquatic organisms that cannot move on their own. An aquatic ecosystem is an ecosystem in a body of water. Communities of organisms that are dependent on each other and on their environment live in aquatic ecosystems. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems. Marine ecosystems can be divided into many zones depending upon water depth and shoreline features. The oceanic zone is the vast open part of the ocean where animals such as whales, sharks, and tuna live. The benthic zone consists of substrates below water where many invertebrates live.

There are three basic types of freshwater ecosystems:

Lentic: slow moving water, including pools, ponds, and lakes.

Lotic: faster moving water, for example streams and rivers.

Wetlands: areas where the soil is saturated or inundated for at least part of the time.