Dredging in the context of "Particle (ecology)"

Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of Rhodophyta (red), Phaeophyta (brown) and Chlorophyta (green) macroalgae. Seaweed species such as kelps provide essential nursery habitat for fisheries and other marine species and thus protect food sources; other species, such as planktonic algae, play a vital role in capturing carbon and producing at least 50% of Earth's oxygen.

Natural seaweed ecosystems are sometimes under threat from human activity. For example, mechanical dredging of kelp destroys the resource and dependent fisheries. Other forces also threaten some seaweed ecosystems; for example, a wasting disease in predators of purple urchins has led to an urchin population surge which has destroyed large kelp forest regions off the coast of California.

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.

Channels are important for the functionality of ports and other bodies of water used for navigability for shipping. Naturally, channels will change their depth and capacity due to erosion and deposition processes. Humans maintain navigable channels by dredging and other engineering processes.

The Shatt al-Arab (Arabic: شط العرب, lit. 'River of the Arabs') is a river about 200 kilometres (120 mi) in length that is formed at the confluence of the Euphrates and Tigris rivers in the town of al-Qurnah in the Basra Governorate of southern Iraq. The southern end of the river constitutes the Iran–Iraq border down to its mouth, where it discharges into the Persian Gulf. The Shatt al-Arab varies in width from about 232 metres (761 ft) at Basra to 800 metres (2,600 ft) at its mouth. It is thought that the waterway formed relatively recently in geological time, with the Tigris and Euphrates originally emptying into the Persian Gulf via a channel further to the west. Kuwait's Bubiyan Island is part of the Shatt al-Arab delta.

The Karun, a tributary which joins the waterway from the Iranian side, deposits large amounts of silt into the river; this necessitates continuous dredging to keep it navigable.

A harbor (American English), or harbour (Commonwealth English; see spelling differences), is a sheltered body of water where ships, boats, and barges can be moored. The term harbor is often used interchangeably with port, which is a man-made facility built for loading and unloading vessels and dropping off and picking up passengers. Harbors usually include one or more ports. Alexandria Port in Egypt, meanwhile, is an example of a port with two harbors.

Harbors may be natural or artificial. An artificial harbor can have deliberately constructed breakwaters, sea walls, or jetties or they can be constructed by dredging, which requires maintenance by further periodic dredging. An example of an artificial harbor is Long Beach Harbor, California, United States, which was an array of salt marshes and tidal flats too shallow for modern merchant ships before it was first dredged in the early 20th century. In contrast, a natural harbor is surrounded on several sides by land. Examples of natural harbors include Sydney Harbour, New South Wales, Australia, Halifax Harbour in Halifax, Nova Scotia, Canada, and Trincomalee Harbour in Sri Lanka.

A body of water, such as a river, canal or lake, is navigable if it is deep, wide and calm enough for a water vessel (e.g. boats) to pass safely. Navigability is also referred to in the broader context of a body of water having sufficient under keel clearance for a vessel.

Such a navigable water is called a waterway, and is preferably with few obstructions against direct traverse that need avoiding, such as rocks, reefs or trees. Bridges built over waterways must have sufficient clearance. High flow speed may make a channel unnavigable due to risk of ship collisions. Waters may be unnavigable because of ice, particularly in winter or high-latitude regions. Navigability also depends on context: a small river may be navigable by smaller craft such as a motorboat or a kayak, but unnavigable by a larger freighter or cruise ship. Shallow rivers may be made navigable by the installation of locks that regulate flow and increase upstream water level, or by dredging that deepens parts of the stream bed.

Newark Bay is a tidal bay at the confluence of the Passaic and Hackensack Rivers in northeastern New Jersey. It is home to the Port Newark-Elizabeth Marine Terminal, the largest container shipping facility in Port of New York and New Jersey, the second busiest in the United States. An estuary, it is periodically dredged to accommodate seafaring ships.

Dubai Creek (Arabic: خُوْر دُبَيّ, romanized: Khūr Dubayy) is a natural saltwater creek in Dubai. It extends about 9 miles (14 km) inwards and forms a natural port that has traditionally been used for trade and transport. The creek ranges from 200 to 1,200 metres (660 to 3,940 ft) in width while the average depth is about 6.5 to 7 metres (21 to 23 ft). Previously, it extended to Ras Al Khor Wildlife Sanctuary but as part of the new Business Bay Canal and Dubai Canal, it extends a further 13 km (8.1 mi) to the Persian Gulf.

In the 1950s, extensive development of the creek began, including dredging and construction of breakwaters. A number of bridges allow movement of vehicles across the creek while abras are used as taxis. The banks and route alongside the creek houses notable government, business and residential areas. A number of tourist locations and hotels are situated along the creek. The Dubai Creek, a vital waterway in the heart of the city, plays a significant role in Dubai's growth by handling the passage of more than 13,000 ships annually. As a major artery for maritime trade, it supports the city's commercial operations. Enhancements to the Creek's infrastructure are being made through a project aimed at improving safety and security measures for maritime traffic and commercial activities. These improvements are expected to strengthen the city's role as a regional hub for trade and ensure smoother, more secure operations for the numerous ships passing through each year.