Stream pool

A stream pool, in hydrology, is a stretch of a river or stream in which the water depth is above average and the water velocity is below average.[1]

Starr 040713-0043 Ficus cf. platypoda
A stream pool in Maui.

Formation

A stream pool may be bedded with sediment or armoured with gravel, and in some cases the pool formations may have been formed as basins in exposed bedrock formations. Plunge pools, or plunge basins, are stream pools formed by the action of waterfalls.

Habitat

This portion of a stream often provides a specialized aquatic ecosystem habitat for organisms that have difficulty feeding or navigating in swifter reaches of the stream, or in seasonally warmer water. Such pools can be important for juvenile fish habitat, especially where many streams reach high summer temperatures and very low-flow dry season characteristics.

See also

Notes

  1. ^ Matthew Chasse, Riffle characteristics in stream investigations Archived 2007-11-01 at the Wayback Machine

External links

Benthos

Benthos is the community of organisms that live on, in, or near the seabed, river, lake, or stream bottom, also known as the benthic zone. This community lives in or near marine or freshwater sedimentary environments, from tidal pools along the foreshore, out to the continental shelf, and then down to the abyssal depths.

Many organisms adapted to deep-water pressure cannot survive in the upperparts of the water column. The pressure difference can be very significant (approximately one atmosphere for each 10 metres of water depth).Because light is absorbed before it can reach deep ocean-water, the energy source for deep benthic ecosystems is often organic matter from higher up in the water column that drifts down to the depths. This dead and decaying matter sustains the benthic food chain; most organisms in the benthic zone are scavengers or detritivores.

The term benthos, coined by Haeckel in 1891, comes from the Greek noun βένθος "depth of the sea". Benthos is used in freshwater biology to refer to organisms at the bottom of freshwater bodies of water, such as lakes, rivers, and streams. There is also a redundant synonym, benthon.

Bride's Pool

Bride's Pool (Chinese: 新娘潭) is a stream pool with several waterfalls in northeastern New Territories, Hong Kong near Tai Mei Tuk. Mirror Pool is also located nearby.

Causapscal River

The Causapscal River () is a waterway of 61.0 kilometres (37.9 mi) located in the Matapedia Valley, in La Matapédia Regional County Municipality, in administrative regions of Bas-Saint-Laurent and Gaspésie-Îles-de-la-Madeleine, in Quebec, Canada. It is a tributary to the Matapedia River; where these two meet is called Les Fourches stream pool.

The Causapscal River flows through the following townships successively:

La Vérendrye (township), in the unorganized territory of Lac-Casault;

Lagrange (township), in the unorganized territory of Ruisseau-des-Mineurs;

Casault (township), in the unorganized territory of Lac-Casault;

Blais (township), in the municipality of Saint-Tharcisius;

Casault (township), in the unorganized territory of Lac-Casault;

Lepage (township), in the municipality of Saint-Alexandre-des-Lacs;

Casupscull (township), in the city of Causapscal.This river of the Matapédia Valley empties into the east bank of the Matapédia River, in the city of Causapscal, at the level of "Les Fourches" salmon pool.

Chalk stream

Chalk streams are streams that flow through chalk hills towards the sea. They are typically wide and shallow, and due to the filtering effect of the chalk their waters are alkaline and very clear. Chalk streams are popular with fly fishermen who fish for trout on these rivers.

Fish pond

A fish pond, or fishpond, is a controlled pond, artificial lake, or reservoir that is stocked with fish and is used in aquaculture for fish farming, or is used for recreational fishing or for ornamental purposes. In the medieval European era it was typical for monasteries and castles (small, partly self-sufficient communities) to have a fish pond.

Fluvial processes

In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluvioglacial is used.

Lemon Stream (Sandy River tributary)

Lemon Stream is a 15.2-mile-long (24.5 km) tributary of the Sandy River, that rises in the New Vineyard mountain range in Franklin County, Maine. Via the Sandy River, it is part of the Kennebec River watershed.

The source of Lemon Stream is a spring located at 1,460 feet (450 m) above sea level between Little Mountain and Caswell Mountain. It flows southeasterly across the northeast corner of Industry, enters Somerset County through the southwest corner of Anson, and then meets the larger Sandy River which forms the southern boundary of Starks. It is not to be confused with the deeply shadowed north-flowing brook in New Portland, Maine of the same name.

Lemon Stream flows from upper level wetlands on the southeastward slopes of the New Vineyard mountains, drops over numerous falls into the fields of upper Lemon Stream valley, then moves south through the sugar maple woodlands into the lower Lemon Stream valley. Here it widens and slows behind a small hydroelectric dam in Starks. Below the dam it snakes further south through more woods and farmland until the shifting sands of its delta yields to the eastward flowing Sandy River.

Lilly Arbor Project

The Lilly Arbor Project is a part of an experimental riparian floodplain reforestation and ecological restoration program, located along the White River in Indiana, in the eastern United States.

Mouth bar

A mouth bar is a bar in a river that is typically created in the middle of a channel in a river delta. It is created by a positive feedback between mid-channel deposition and flow divergence. As the flow diverges near the ocean, sediment settles out in the channel and creates an incipient mouth bar. As flow is routed around the incipient bar, additional sediment is deposited on the incipient bar. This continued process results in the formation of a full-fledged mouth bar, which causes the channel to bifurcate. This continued process leads to the characteristic fractal tree pattern found in some prograding river-dominated deltas.

Oxbow lake

An oxbow lake is a U-shaped lake that forms when a wide meander of a river is cut off, creating a free-standing body of water. This landform is so named for its distinctive curved shape, which resembles the bow pin of an oxbow. In Australia, an oxbow lake is called a billabong, from the indigenous Wiradjuri language. In south Texas, oxbows left by the Rio Grande are called resacas.

The word "oxbow" can also refer to a U-shaped bend in a river or stream, whether or not it is cut off from the main stream.

Particle (ecology)

In marine and freshwater ecology, a particle is a small object. Particles can remain in suspension in the ocean or freshwater. However, they eventually settle (rate determined by Stokes' law) and accumulate as sediment. Some can enter the atmosphere through wave action where they can act as cloud condensation nuclei (CCN). Many organisms filter particles out of the water with unique filtration mechanisms (filter feeders). Particles are often associated with high loads of toxins which attach to the surface. As these toxins are passed up the food chain they accumulate in fatty tissue and become increasingly concentrated in predators (see bioaccumulation). Very little is known about the dynamics of particles, especially when they are re-suspended by dredging. They can remain floating in the water and drift over long distances. The decomposition of some particles by bacteria consumes a lot of oxygen and can cause the water to become hypoxic.

Photic zone

The photic zone, euphotic zone (Greek for "well lit": εὖ "well" + φῶς "light"), or sunlight (or sunlit) zone is the uppermost layer of water in a lake or ocean that is exposed to intense sunlight. It corresponds roughly to the layer above the compensation point, i.e. depth where the rate of carbon dioxide uptake, or equivalently, the rate of photosynthetic oxygen production, is equal to the rate of carbon dioxide production, equivalent to the rate of respiratory oxygen consumption, i.e. the depth where net carbon dioxide assimilation is zero.

It extends from the surface down to a depth where light intensity falls to one percent of that at the surface, called the euphotic depth. Accordingly, its thickness depends on the extent of light attenuation in the water column. Typical euphotic depths vary from only a few centimetres in highly turbid eutrophic lakes, to around 200 meters in the open ocean. It also varies with seasonal changes in turbidity.

Since the photic zone is where almost all of the photosynthesis occurs, the depth of the photic zone is generally proportional to the level of primary production that occurs in that area of the ocean. About 90% of all marine life lives in the photic zone. A small amount of primary production is generated deep in the abyssal zone around the hydrothermal vents which exist along some mid-oceanic ridges.

The zone which extends from the base of the euphotic zone to about 200 metres is sometimes called the disphotic zone. While there is some light, it is insufficient for photosynthesis, or at least insufficient for photosynthesis at a rate greater than respiration. The euphotic zone together with the disphotic zone coincides with the epipelagic zone. The bottommost zone, below the euphotic zone, is called the aphotic zone. Most deep ocean waters belong to this zone.

The transparency of the water, which determines the depth of the photic zone, is measured simply with a Secchi disk. It may also be measured with a photometer lowered into the water.

Pond

A pond is an area filled with water, either natural or artificial, that is smaller than a lake. It may arise naturally in floodplains as part of a river system, or be a somewhat isolated depression (such as a kettle, vernal pool, or prairie pothole). It may contain shallow water with marsh and aquatic plants and animals.Factors impacting the type of life found in a pond include depth and duration of water level, nutrient level, shade, presence or absence of inlets and outlets, effects of grazing animals, and salinity.Ponds are frequently man-made, or expanded beyond their original depth and bounds. Among their many uses, ponds provide water for agriculture and livestock, aid in habitat restoration, serve as fish hatcheries, are components of landscape architecture, may store thermal energy as solar ponds, and treat wastewater as treatment ponds.

Ponds may be fresh, saltwater, or brackish.

Ramsar site

A Ramsar site is a wetland site designated to be of international importance under the Ramsar Convention.The Convention on Wetlands, known as the Ramsar Convention, is an intergovernmental environmental treaty established in 1971 by UNESCO, which came into force in 1975. It provides for national action and international cooperation regarding the conservation of wetlands, and wise sustainable use of their resources.Ramsar identifies wetlands of international importance, especially those providing waterfowl habitat.

As of 2016, there were 2,231 Ramsar sites, protecting 214,936,005 hectares (531,118,440 acres), and 169 national governments are currently participating.

Reach (geography)

A reach is a length of a stream or river, usually suggesting a level, uninterrupted stretch. The beginning and ending points may be selected for geographic, historical or other reasons – and may be based on landmarks such as gauging stations, river miles, natural features, and topography.

A reach may also be an expanse, or widening, of a stream or river channel. This commonly occurs after the river or stream is dammed. A reach is similar to an arm. The term "reach" can also refer to:

An extended portion or stretch of land or water;

a straight portion of a stream or river, as from one turn to another;

a level stretch, as between locks in a canal;

an arm of the sea extending up into the land.As of 2015, the US Board on Geographic Names records 334 place names in the US with the characterization of a named "reach".

Vector (epidemiology)

In epidemiology, a disease vector is any agent who carries and transmits an infectious pathogen into another living organism; most agents regarded as vectors are organisms, such as intermediate parasites or microbes, but it could be an inanimate medium of infection such as dust particles.

Väinämöinen

Väinämöinen (Finnish pronunciation: [ˈʋæinæˌmøinen]) is a demigod, hero and the central character in Finnish folklore and the main character in the national epic Kalevala. His name comes from the Finnish word väinä, meaning stream pool. Väinämöinen was described as an old and wise man, and he possessed a potent, magical voice.

Waterfall

A waterfall is an area where water flows over a vertical drop or a series of steep drops in the course of a stream or river. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf.

Large-scale features
Alluvial rivers
Bedrock river
Bedforms
Regional processes
Mechanics
Aquatic ecosystems
Ponds, Pools, and Puddles
Ponds
Pools
Puddles
Biota
Ecosystems
Related

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.