An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world.
A braided river consists of a network of river channels separated by small, often temporary, islands called braid bars or, in British English usage, aits or eyots.
A River Delta is a landform shaped like a triangle, created by the deposition of sediment that is carried by a river and enters slower-moving or stagnant water. This occurs at a river mouth, when it enters an ocean, sea, estuary, lake, reservoir, or another river that cannot carry away the supplied sediment. It is so named because its triangle shape resembles the uppercase Greek letter delta, Δ. The size and shape of a delta are controlled by the balance between watershed processes that supply sediment, and receiving basin processes that redistribute, sequester, and export that sediment. The size, geometry, and location of the receiving basin also plays an important role in delta evolution.
In ecology, a marsh is a wetland that is dominated by herbaceous plants rather than by woody plants. More in general, the word can be used for any low-lying and seasonally waterlogged terrain. In Europe and in agricultural literature low-lying meadows that require draining and embanked polderlands are also referred to as marshes or marshland.
The Miramichi River is a river located in the east-central part of New Brunswick, Canada. The river drains into Miramichi Bay in the Gulf of St. Lawrence. The name may have been derived from the Montagnais words "Maissimeu Assi", and it is today the namesake of the Miramichi Herald at the Canadian Heraldic Authority.
In oceanography, geomorphology, and geoscience, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material, and rises from the bed of a body of water close to the surface or above it, which poses a danger to navigation. Shoals are also known as sandbanks, sandbars, or gravelbars. Two or more shoals that are either separated by shared troughs or interconnected by past or present sedimentary and hydrographic processes are referred to as a shoal complex.
Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.
The Sudd is a vast swamp in South Sudan, formed by the White Nile's Baḥr al-Jabal section. The Arabic word sudd is derived from sadd, meaning "barrier" or "obstruction". The term "the sudd" has come to refer to any large solid floating vegetation island or mat. The area which the swamp covers is one of the world's largest wetlands and the largest freshwater wetland in the Nile Basin.
In physical geography and hydrology, a channel is a landform on which a relatively narrow body of water is situated, such as a river, river delta or strait. While channel typically refers to a natural formation, the cognate term canal denotes a similar artificial structure.
A tidal marsh is a marsh found along rivers, coasts and estuaries which floods and drains by the tidal movement of the adjacent estuary, sea or ocean. Tidal marshes experience many overlapping persistent cycles, including diurnal and semi-diurnal tides, day-night temperature fluctuations, spring-neap tides, seasonal vegetation growth and decay, upland runoff, decadal climate variations, and centennial to millennial trends in sea level and climate.
Miramichi Bay is an estuary located on the west coast of the Gulf of St. Lawrence in New Brunswick, at the mouth of the Miramichi River. Miramichi Bay is separated into the "inner bay" and the "outer bay", with the division being a line of uninhabited barrier islands which are continually reshaped by ocean storms. The largest of these islands is the uninhabited Portage Island, which was broken in two during a violent storm in the 1950s. The islands provide some protection to the inner bay from ocean storms in the Gulf of St. Lawrence.
An aquatic ecosystem is an ecosystem found in and around a body of water, in contrast to land-based terrestrial ecosystems. Aquatic ecosystems contain communities of organisms—aquatic life—that are dependent on each other and on their environment. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems. Freshwater ecosystems may be lentic ; lotic ; and wetlands.
River engineering is a discipline of civil engineering which studies human intervention in the course, characteristics, or flow of a river with the intention of producing some defined benefit. People have intervened in the natural course and behaviour of rivers since before recorded history—to manage the water resources, to protect against flooding, or to make passage along or across rivers easier. Since the Yuan Dynasty and Ancient Roman times, rivers have been used as a source of hydropower. From the late 20th century, the practice of river engineering has responded to environmental concerns broader than immediate human benefit. Some river engineering projects have focused exclusively on the restoration or protection of natural characteristics and habitats.
The following outline is provided as an overview of and introduction to Oceanography.
A stream is a continuous body of surface water flowing within the bed and banks of a channel. Depending on its location or certain characteristics, a stream may be referred to by a variety of local or regional names. Long, large streams are usually called rivers, while smaller, less voluminous and more intermittent streams are known as streamlets, brooks or creeks.
A river is a natural freshwater stream that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it runs out of water, or only flow during certain seasons. Rivers are regulated by the water cycle, the processes by which water moves around the Earth. Water first enters rivers through precipitation, whether from the runoff of water down a slope, the melting of glaciers or snow, or seepage from aquifers beneath the surface of the Earth.
A lake is an often naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from the ocean, although they may be connected with the ocean by rivers. Most lakes are freshwater and account for almost all the world's surface freshwater, but some are salt lakes with salinities even higher than that of seawater. Lakes vary significantly in surface area and volume of water.
Reedy Lake, historically also known as Lake Reedy, is a shallow 5.5-square-kilometre (2.1 sq mi) intermittent freshwater lake or swamp on the lower reaches of the Barwon River, on the Bellarine Peninsula southeast of Geelong in the Australian state of Victoria.
The Lake Superior National Estuarine Research Reserve includes land and water areas along the St. Louis River and Lake Superior in Douglas County, in the northwest corner of Wisconsin, United States. It is one of 29 National Estuarine Research Reserves. The Reserve is operated as a program of the Natural Resources Institute of the University of Wisconsin-Madison Division of Extension. It has an area of 16,697 acres (6,757 ha), and was designated in 2010.
A hapua is a river-mouth lagoon on a mixed sand and gravel (MSG) beach, formed at the river-coast interface where a typically braided, although sometimes meandering, river interacts with a coastal environment that is significantly affected by longshore drift. The lagoons which form on the MSG coastlines are common on the east coast of the South Island of New Zealand and have long been referred to as hapua by Māori people. This classification differentiates hapua from similar lagoons located on the New Zealand coast termed waituna.
