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72-531: Axim is a coastal town and the capital of Nzema East Municipal district , a district in Western Region of South Ghana . Axim lies 64 kilometers west of the port city of Sekondi-Takoradi in the Western Region , west of Cape Three Points . Axim has a 2013 settlement population of 27,719 people. This area was occupied by the Nzema people. The Portuguese arrived by the early 16th century as traders. They built

144-527: A navy and some form of coast guard . Coasts, especially those with beaches and warm water, attract tourists often leading to the development of seaside resort communities. In many island nations such as those of the Mediterranean , South Pacific Ocean and Caribbean , tourism is central to the economy . Coasts offer recreational activities such as swimming, fishing, surfing, boating, and sunbathing . Growth management and coastal management can be

216-478: A challenge for coastal local authorities who often struggle to provide the infrastructure required by new residents, and poor management practices of construction often leave these communities and infrastructure vulnerable to processes like coastal erosion and sea level rise . In many of these communities, management practices such as beach nourishment or when the coastal infrastructure is no longer financially sustainable, managed retreat to remove communities from

288-415: A feature of shellfish consumption. When served freshly shucked (opened) and iced, one may find a liquid inside the shell, called the liquor. Some believe that oysters have the properties of an aphrodisiac . Inter-tidal herbivorous shellfish such as mussels and clams can help people reach a healthy balance of omega-3 and omega-6 fats in their diets, instead of the current Western diets . For this reason,

360-517: A few species of land crabs are eaten, for example Cardisoma guanhumi in the Caribbean . Shellfish are among the most common food allergens . Despite the name, shellfish are not fish . Most shellfish are low on the food chain and eat a diet composed primarily of phytoplankton and zooplankton . Many varieties of shellfish, and crustaceans in particular, are actually closely related to insects and arachnids ; crustaceans make up one of

432-655: A much higher capacity for carbon sequestration than many terrestrial ecosystems , and as such can play a critical role in the near-future to help mitigate climate change effects by uptake of atmospheric anthropogenic carbon dioxide . However, the economic importance of coasts makes many of these communities vulnerable to climate change , which causes increases in extreme weather and sea level rise, as well as related issues like coastal erosion , saltwater intrusion , and coastal flooding . Other coastal issues, such as marine pollution , marine debris , coastal development, and marine ecosystem destruction, further complicate

504-569: A prominent seaside fort, Fort Santo Antonio , in 1515. They exported some Africans as slaves to Europe and the Americas. Between 1642 and 1872, the fort was expanded and altered by the Dutch , who "ruled" during that period. The fort, now property of Ghana, is open to the public. Off-shore are some picturesque islands , including one with a lighthouse . The town of Axim is divided into two parts: Upper Axim and Lower Axim. Fort Santo Antonio lies roughly on

576-625: A proper name to the coast of the Ligurian Sea , in the form riviera ligure , then shortened to riviera . Historically, the Ligurian Riviera extended from Capo Corvo (Punta Bianca) south of Genoa , north and west into what is now French territory past Monaco and sometimes as far as Marseilles . Today, this coast is divided into the Italian Riviera and the French Riviera , although

648-435: A provider of sediment for coastlines of tropical islands. Like the ocean which shapes them, coasts are a dynamic environment with constant change. The Earth 's natural processes, particularly sea level rises , waves and various weather phenomena, have resulted in the erosion , accretion and reshaping of coasts as well as flooding and creation of continental shelves and drowned river valleys ( rias ). More and more of

720-456: A shoreline configuration. Swash is the shoreward flow after the break, backwash is the water flow back down the beach. The relative strength of flow in the swash and backwash determines what size grains are deposited or eroded. This is dependent on how the wave breaks and the slope of the shore. Depending on the form of the breaking wave, its energy can carry granular material up the beach and deposit it, or erode it by carrying more material down

792-425: A slightly different way in discussions of legal and economic boundaries (see territorial waters and international waters ) or when considering the geography of coastal landforms or the ecological systems operating through the continental shelf ( marine coastal ecosystems ). The research on coastal waters often divides into these separate areas too. The dynamic fluid nature of the ocean means that all components of

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864-530: A spice with extremely strong, hot flavor), thinly sliced pickled ginger root, and a simple garnish such as shiso (a kitchen herb, member of the mint family) or finely shredded daikon radish, or both. Lobster in particular is a great delicacy in the United States , where families in the Northeast region make them into the centerpiece of a clam bake , usually for special occasions. Lobsters are eaten on much of

936-536: A toxic effect. Some shellfish, such as whelk , contain arsenic . A sample of whelk was found to have a total content of arsenic at 15.42 mg/kg of which 1% is inorganic arsenic. Shellfish caught in Alaska can cause paralytic shellfish poisoning (PSP). PSP is caused by toxins, namely saxitoxin, released by dinoflagellates , a type of protista (also considered algae), which are extremely poisonous (1000 times more potent than cyanide) and can lead to death by paralyzing

1008-457: A wide range of biodiversity . On land, they harbor important ecosystems such as freshwater or estuarine wetlands , which are important for bird populations and other terrestrial animals . In wave-protected areas, they harbor salt marshes , mangroves or seagrasses , all of which can provide nursery habitat for fin fish , shellfish , and other aquatic animals . Rocky shores are usually found along exposed coasts and provide habitat for

1080-529: A wide range of sessile animals (e.g. mussels , starfish , barnacles ) and various kinds of seaweeds . In physical oceanography , a shore is the wider fringe that is geologically modified by the action of the body of water past and present, while the beach is at the edge of the shore, representing the intertidal zone where there is one. Along tropical coasts with clear, nutrient-poor water, coral reefs can often be found between depths of 1–50 m (3.3–164.0 ft). According to an atlas prepared by

1152-541: Is a coastline that has experienced a fall in sea level, because of either a global sea-level change, or local uplift. Emergent coastlines are identifiable by the coastal landforms , which are above the high tide mark, such as raised beaches . In contrast, a submergent coastline is one where the sea level has risen, due to a global sea-level change, local subsidence , or isostatic rebound . Submergent coastlines are identifiable by their submerged, or "drowned" landforms, such as rias (drowned valleys) and fjords According to

1224-528: Is connected to marine pollution which can occur from a number of sources: Marine debris (garbage and industrial debris); the transportation of petroleum in tankers , increasing the probability of large oil spills ; small oil spills created by large and small vessels, which flush bilge water into the ocean. Marine pollution occurs when substances used or spread by humans, such as industrial , agricultural and residential waste , particles , noise , excess carbon dioxide or invasive organisms enter

1296-415: Is extremely important to geologists. These provide vital clues for reconstructing the geography of ancient continents ( paleogeography ). The locations of these beds show the extent of ancient seas at particular points in geological time, and provide clues to the magnitudes of tides in the distant past. Sediments deposited in the shoreface are preserved as lenses of sandstone in which the upper part of

1368-408: Is more important. Macrotidal coasts lack barrier islands and lagoons , and are characterized by funnel-shaped estuaries containing sand ridges aligned with tidal currents. Wave action is much more important for determining bedforms of sediments deposited along mesotidal and microtidal coasts than in macrotidal coasts. Waves erode coastline as they break on shore releasing their energy; the larger

1440-423: Is moved along the coastline by the waves. This forms an abrasion or cliffed coast . Sediment deposited by rivers is the dominant influence on the amount of sediment located in the case of coastlines that have estuaries. Today, riverine deposition at the coast is often blocked by dams and other human regulatory devices, which remove the sediment from the stream by causing it to be deposited inland. Coral reefs are

1512-518: Is often narrowly defined as filter-feeding molluscs such as clams, mussels, and oyster to the exclusion of crustaceans and all else. Although the term is primarily applied to marine species, edible freshwater invertebrates such as crayfish and river mussels are also sometimes grouped under the umbrella term "shellfish". Although their shells may differ, all shellfish are invertebrates. As non-mammalian animals that spend their entire lives in water they are "fish" in an informal sense; however,

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1584-412: Is the counterintuitive observation that the coastline of a landmass does not have a well-defined length. This results from the fractal curve –like properties of coastlines; i.e., the fact that a coastline typically has a fractal dimension . Although the "paradox of length" was previously noted by Hugo Steinhaus , the first systematic study of this phenomenon was by Lewis Fry Richardson , and it

1656-456: The Aegean Sea . The following articles describe some coastal landforms: "Coastal waters" (or "coastal seas") is a rather general term used differently in different contexts, ranging geographically from the waters within a few kilometers of the coast, through to the entire continental shelf which may stretch for more than a hundred kilometers from land. Thus the term coastal waters is used in

1728-614: The Gulf of Mexico and the Atlantic Ocean to satisfy a national demand for shrimp. Locally, prawns and shrimp are often deep fried; in the Cajun and Creole kitchens of Louisiana , shrimp and prawns are a common addition to traditional recipes like jambalaya and certain stews. Crawfish are a well known and much eaten delicacy there, often boiled in huge pots and heavily spiced. In many major cities with active fishing ports, raw oyster bars are also

1800-452: The US EPA considers this region to extend much further offshore. "Coastal waters" has specific meanings in the context of commercial coastal shipping , and somewhat different meanings in the context of naval littoral warfare . Oceanographers and marine biologists have yet other takes. Coastal waters have a wide range of marine habitats from enclosed estuaries to the open waters of

1872-610: The United Nations , about 44% of the human population lives within 150 km (93 mi) of the sea as of 2013 . Due to its importance in society and its high population concentrations, the coast is important for major parts of the global food and economic system, and they provide many ecosystem services to humankind. For example, important human activities happen in port cities. Coastal fisheries (commercial, recreational, and subsistence) and aquaculture are major economic activities and create jobs, livelihoods, and protein for

1944-670: The Western Interior Seaway , a shallow sea that flooded central North America during the late Cretaceous Period (about 100 to 66 million years ago). These are beautifully exposed along the Book Cliffs of Utah and Colorado . The following articles describe the various geologic processes that affect a coastal zone: Larger animals that live in coastal areas include puffins , sea turtles and rockhopper penguins , among many others. Sea snails and various kinds of barnacles live on rocky coasts and scavenge on food deposited by

2016-422: The cuisine of New England . The soft-shelled clam is eaten either fried or steamed (and then called " steamers "). Many types of clams can be used for clam chowder , but the quahog , a hard shelled clam also known as a chowder clam, is often used because the long cooking time softens its tougher meat. The Chesapeake Bay and Maryland region has generally been associated more with crabs, but in recent years

2088-469: The ocean and cause harmful effects there. The majority of this waste (80%) comes from land-based activity, although marine transportation significantly contributes as well. It is a combination of chemicals and trash, most of which comes from land sources and is washed or blown into the ocean. This pollution results in damage to the environment, to the health of all organisms, and to economic structures worldwide. Since most inputs come from land, either via

2160-596: The ocean . Floating oceanic debris tends to accumulate at the center of gyres and on coastlines, frequently washing aground, when it is known as beach litter or tidewrack. Deliberate disposal of wastes at sea is called ocean dumping . Naturally occurring debris, such as driftwood and drift seeds , are also present. With the increasing use of plastic , human influence has become an issue as many types of (petrochemical) plastics do not biodegrade quickly, as would natural or organic materials. The largest single type of plastic pollution (~10%) and majority of large plastic in

2232-444: The rivers , sewage or the atmosphere, it means that continental shelves are more vulnerable to pollution. Air pollution is also a contributing factor by carrying off iron, carbonic acid, nitrogen , silicon, sulfur, pesticides or dust particles into the ocean. The pollution often comes from nonpoint sources such as agricultural runoff , wind-blown debris , and dust. These nonpoint sources are largely due to runoff that enters

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2304-630: The East Coast; the American lobster ranges from Newfoundland down to about the Carolinas , but is most often associated with Maine . A typical meal involves boiling the lobster with some slight seasoning and then serving it with drawn butter, baked potato , and corn on the cob . Clamming is done both commercially and recreationally along the Northeast coastline of the US. Various type of clams are incorporated into

2376-736: The French use the term "Riviera" to refer to the Italian Riviera and call the French portion the "Côte d'Azur". As a result of the fame of the Ligurian rivieras, the term came into English to refer to any shoreline, especially one that is sunny, topographically diverse and popular with tourists. Such places using the term include the Australian Riviera in Queensland and the Turkish Riviera along

2448-534: The United Nations has declared 2021–2030 the UN Decade on Ecosystem Restoration , but restoration of coastal ecosystems has received insufficient attention. Since coasts are constantly changing, a coastline's exact perimeter cannot be determined; this measurement challenge is called the coastline paradox . The term coastal zone is used to refer to a region where interactions of sea and land processes occur. Both

2520-470: The area also has three tourist beach resorts as well as coconut and rubber plantations. The scenic and fertile terrain features many palm trees . Local artisanal miners pan for gold in streams inland from Axim. Axim has a transport station, two major bank branches, and some rural banks including the Ahantaman Rural Bank, Nzema Maanle Rural Bank, Lower Pra Rural Bank. Every August,

2592-486: The area has been trying to reduce its catch of blue crabs , as wild populations have been depleted. This has not, however, stemmed the demand: Maryland-style crabcakes are still a well known treat in crabhouses all over the bay, though the catch now comes from points farther south. In the Southeast , and particularly the gulf states, shrimping is an important industry. Copious amounts of shrimp are harvested each year in

2664-571: The average sea level rose by 15–25 cm (6–10 in), with an increase of 2.3 mm (0.091 in) per year since the 1970s. This was faster than the sea level had ever risen over at least the past 3,000 years. The rate accelerated to 4.62 mm (0.182 in)/yr for the decade 2013–2022. Climate change due to human activities is the main cause. Between 1993 and 2018, melting ice sheets and glaciers accounted for 44% of sea level rise , with another 42% resulting from thermal expansion of water . International attention to address

2736-417: The average wind wave and swell conditions are relatively mild. Low energy coasts typically change slowly, and tend to be depositional environments. High energy coasts are exposed to the direct impact of waves and storms, and are generally erosional environments. High energy storm events can make large changes to a coastline, and can move significant amounts of sediment over a short period, sometimes changing

2808-410: The breathing muscles. Due to warming oceans, algae blooms have become more widespread, thereby increasing the likelihood of intoxications of various types. Shellfish of various kinds contribute to the formation of reefs , such as when millions of oysters or mussels aggregate together. Reefs provide habitat for numerous other species, bury carbon, contributing to climate change mitigation , and defend

2880-461: The coast of Wales and other countries. Coastal fish , also called inshore fish or neritic fish, inhabit the sea between the shoreline and the edge of the continental shelf . Since the continental shelf is usually less than 200 metres (660 ft) deep, it follows that pelagic coastal fish are generally epipelagic fish , inhabiting the sunlit epipelagic zone . Coastal fish can be contrasted with oceanic fish or offshore fish , which inhabit

2952-812: The coast. Estuarine and marine coastal ecosystems are both marine ecosystems . Together, these ecosystems perform the four categories of ecosystem services in a variety of ways: The provisioning services include forest products, marine products, fresh water , raw materials, biochemical and genetic resources. Regulating services include carbon sequestration (contributing to climate change mitigation ) as well as waste treatment and disease regulation and buffer zones. Supporting services of coastal ecosystems include nutrient cycling , biologically mediated habitats and primary production . Cultural services of coastal ecosystems include inspirational aspects, recreation and tourism , science and education. According to one principle of classification, an emergent coastline

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3024-567: The continental shelf. Similarly, the term littoral zone has no single definition. It is the part of a sea , lake , or river that is close to the shore . In coastal environments, the littoral zone extends from the high water mark , which is rarely inundated, to shoreline areas that are permanently submerged . Coastal waters can be threatened by coastal eutrophication and harmful algal blooms . The identification of bodies of rock formed from sediments deposited in shoreline and nearshore environments (shoreline and nearshore facies )

3096-555: The deep seas beyond the continental shelves. Many coastal areas are famous for their kelp beds. Kelp is a fast-growing seaweed that can grow up to half a meter a day in ideal conditions. Mangroves , seagrasses , macroalgal beds, and salt marsh are important coastal vegetation types in tropical and temperate environments respectively. Restinga is another type of coastal vegetation. Coasts also face many human-induced environmental impacts and coastal development hazards . The most important ones are: The pollution of coastlines

3168-519: The division between the two parts, but closest to the centre of Upper Axim, the original European settlement. Here, several large mansions of lumber-trading magnates and other businessmen remain from the late 19th century and period of the British empire. Axim is governed by a political District Executive of the Nzema East Municipality . The economy is based mainly on Axim's fishing fleet , but

3240-596: The eating of shellfish is often encouraged by dietitians. Some popular dishes using shellfish: The Torah forbids the consumption of shellfish (i.e. the only permitted seafood is fish with fins and scales), in the books of Leviticus and Deuteronomy . Jews (of all religious traditions) who fully observe the dietary laws thus do not eat shellfish, neither do Seventh-day Adventists , who also follow Jewish dietary law. Shia Islamic schools of thought vary on whether (and which types of) shellfish may be acceptable. Sunni Muslims view them as halal . Approximately 1% of

3312-777: The human uses of the coast and threaten coastal ecosystems. The interactive effects of climate change, habitat destruction , overfishing , and water pollution (especially eutrophication ) have led to the demise of coastal ecosystem around the globe. This has resulted in population collapse of fisheries stocks, loss of biodiversity , increased invasion of alien species , and loss of healthy habitats. International attention to these issues has been captured in Sustainable Development Goal 14 "Life Below Water", which sets goals for international policy focused on preserving marine coastal ecosystems and supporting more sustainable economic practices for coastal communities. Likewise,

3384-616: The latter due to the northern extension of the cold, foggy Beneguela Current — but some rainfall is seen even in these periods. May and June are the wettest months with rainfall typically over 300 millimetres or 12 inches in May and over 450 millimetres or 18 inches in June. [REDACTED] Media related to Axim at Wikimedia Commons 4°52′N 2°14′W  /  4.867°N 2.233°W  / 4.867; -2.233 Coast Coasts are important zones in natural ecosystems , often home to

3456-638: The main subphyla of the phylum Arthropoda . Molluscs include cephalopods (squids, octopuses, cuttlefish) and bivalves (clams, oysters), as well as gastropods (aquatic species such as whelks and winkles; land species such as snails and slugs). Molluscs used as a food source by humans include many species of clams , mussels , oysters , winkles , and scallops . Some crustaceans that are commonly eaten are shrimp , lobsters , crayfish , crabs and barnacles . Echinoderms are not as frequently harvested for food as molluscs and crustaceans; however, sea urchin gonads are quite popular in many parts of

3528-694: The major festivals of Kundum takes place, coinciding with the best fishing -catch of the year; people come to Axim for the festivities and to fish and trade. There is a wonderful beach in Axim. The very place around the beach, perched on a hillside, is an exuberant nature has no equal in Ghana. The waves of the beach are strong and suitable for surfers. Axim has a tropical monsoon climate ( Köppen Am ) with oppressively hot and humid weather year-round. There are two dry seasons in January-February and August-September —

3600-410: The majority of coastal human populations. Other coastal spaces like beaches and seaside resorts generate large revenues through tourism . Marine coastal ecosystems can also provide protection against sea level rise and tsunamis . In many countries, mangroves are the primary source of wood for fuel (e.g. charcoal ) and building material. Coastal ecosystems like mangroves and seagrasses have

3672-669: The margins of the continental shelves , make up about 7 percent of the Earth's oceans, but at least 85% of commercially harvested fish depend on coastal environments during at least part of their life cycle. As of October 2010, about 2.86% of exclusive economic zones were part of marine protected areas . The definition of coasts varies. Marine scientists think of the "wet" (aquatic or intertidal ) vegetated habitats as being coastal ecosystems (including seagrass, salt marsh etc.) whilst some terrestrial scientists might only think of coastal ecosystems as purely terrestrial plants that live close to

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3744-587: The microplastics go through the water filtration system and into the ocean, but because of their small size they are likely to escape capture by the preliminary treatment screens on wastewater plants. These beads are harmful to the organisms in the ocean, especially filter feeders, because they can easily ingest the plastic and become sick. The microplastics are such a concern because it is difficult to clean them up due to their size, so humans can try to avoid using these harmful plastics by purchasing products that use environmentally safe exfoliates. Between 1901 and 2018,

3816-507: The more resistant rocks erode more slowly, remaining as headlands or outcroppings . Parts of a coastline can be categorised as high energy coast or low energy coast. The distinguishing characteristics of a high energy coast are that the average wave energy is relatively high so that erosion of small grained material tends to exceed deposition, and consequently landforms like cliffs, headlands and wave-cut terraces develop. Low energy coasts are generally sheltered from waves, or in regions where

3888-441: The ocean through rivers, but wind-blown debris and dust can also play a role, as these pollutants can settle into waterways and oceans. Pathways of pollution include direct discharge, land runoff, ship pollution , bilge pollution , atmospheric pollution and, potentially, deep sea mining . Marine debris , also known as marine litter, is human-created solid material that has deliberately or accidentally been released in seas or

3960-485: The oceans is discarded and lost nets from the fishing industry. Waterborne plastic poses a serious threat to fish , seabirds , marine reptiles , and marine mammals , as well as to boats and coasts. A growing concern regarding plastic pollution in the marine ecosystem is the use of microplastics. Microplastics are beads of plastic less than 5 millimeters wide, and they are commonly found in hand soaps, face cleansers, and other exfoliators. When these products are used,

4032-546: The population is estimated to suffer from shellfish allergy, which is more common in teenage and adult life than very early childhood. There is some evidence that shellfish intolerance exists in an unknown proportion of the population. The symptoms of this do not include the immune and respiratory symptoms of an allergic reaction, such as hives, hyperventilation, or anaphylaxis, but do involve gastrointestinal distress, such as nausea, abdominal cramps, and diarrhea. Similar symptoms can come from foodborne illness or as part of

4104-624: The present, shellfish dishes are a feature of almost all the cuisines of the world, providing an important source of protein in many cuisines around the world, especially in the countries with coastal areas. In Japanese cuisine , chefs often use shellfish and their roe in different dishes. Sushi (vinegared rice, topped with other ingredients, including shellfish, fish, meat and vegetables) features both raw and cooked shellfish. Sashimi primarily consists of very fresh raw seafood, sliced into thin pieces. Both sushi and sashimi are served with soy sauce and wasabi paste (a Japanese horseradish root,

4176-416: The sandstone is coarser than the lower part (a coarsening upwards sequence ). Geologists refer to these are parasequences . Each records an episode of retreat of the ocean from the shoreline over a period of 10,000 to 1,000,000 years. These often show laminations reflecting various kinds of tidal cycles. Some of the best-studied shoreline deposits in the world are found along the former western shore of

4248-579: The sea. Some coastal animals are used to humans in developed areas, such as dolphins and seagulls who eat food thrown for them by tourists. Since the coastal areas are all part of the littoral zone , there is a profusion of marine life found just off-coast, including sessile animals such as corals , sponges, starfish, mussels, seaweeds, fishes, and sea anemones . There are many kinds of seabirds on various coasts. These include pelicans and cormorants , who join up with terns and oystercatchers to forage for fish and shellfish. There are sea lions on

4320-401: The seashore (see also estuaries and coastal ecosystems ). While there is general agreement in the scientific community regarding the definition of coast, in the political sphere, the delineation of the extents of a coast differ according to jurisdiction . Government authorities in various countries may define coast differently for economic and social policy reasons. The coastline paradox

4392-427: The second principle of classification, a concordant coastline is a coastline where bands of different rock types run parallel to the shore. These rock types are usually of varying resistance , so the coastline forms distinctive landforms, such as coves. Discordant coastlines feature distinctive landforms because the rocks are eroded by the ocean waves . The less resistant rocks erode faster, creating inlets or bay ;

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4464-404: The slope than up it. Steep waves that are close together and break with the surf plunging down onto the shore slope expend much of their energy lifting the sediment. The weak swash does not carry it far up the slope, and the strong backwash carries it further down the slope, where it either settles in deeper water or is carried along the shore by a longshore current induced by an angled approach of

4536-424: The term ”finfish" is sometimes used to distinguish fish , animals defined by having vertebrae , from shellfish in modern terminology. The word "shellfish" is both singular and plural; the rarely used "shellfishes" is sometimes employed to distinguish among various types of shellfish. Archaeological finds have shown that humans have been making use of shellfish as a food item for hundreds of thousands of years. In

4608-692: The terms coast and coastal are often used to describe a geographic location or region located on a coastline (e.g., New Zealand's West Coast , or the East , West , and Gulf Coast of the United States .) Coasts with a narrow continental shelf that are close to the open ocean are called pelagic coast , while other coasts are more sheltered coast in a gulf or bay . A shore , on the other hand, may refer to parts of land adjoining any large body of water, including oceans (sea shore) and lakes (lake shore). The Earth has approximately 620,000 kilometres (390,000 mi) of coastline. Coastal habitats, which extend to

4680-776: The threats of coasts has been captured in Sustainable Development Goal 14 "Life Below Water" which sets goals for international policy focused on preserving marine coastal ecosystems and supporting more sustainable economic practices for coastal communities. Likewise, the United Nations has declared 2021–2030 the UN Decade on Ecosystem Restoration , but restoration of coastal ecosystems has received insufficient attention. Shellfish Shellfish , in colloquial and fisheries usage, are exoskeleton -bearing aquatic invertebrates used as food , including various species of molluscs , crustaceans , and echinoderms . Although most kinds of shellfish are harvested from saltwater environments, some are found in freshwater . In addition,

4752-487: The wave the more energy it releases and the more sediment it moves. Coastlines with longer shores have more room for the waves to disperse their energy, while coasts with cliffs and short shore faces give little room for the wave energy to be dispersed. In these areas, the wave energy breaking against the cliffs is higher, and air and water are compressed into cracks in the rock, forcing the rock apart, breaking it down. Sediment deposited by waves comes from eroded cliff faces and

4824-476: The wave-front to the shore. These waves which erode the beach are called destructive waves. Low waves that are further apart and break by spilling , expend more of their energy in the swash which carries particles up the beach, leaving less energy for the backwash to transport them downslope, with a net constrictive influence on the beach. Riviera is an Italian word for "shoreline", ultimately derived from Latin ripa ("riverbank"). It came to be applied as

4896-407: The waves surge up the river estuaries from the ocean. Geologists classify coasts on the basis of tidal range into macrotidal coasts with a tidal range greater than 4 m (13 ft); mesotidal coasts with a tidal range of 2 to 4 m (6.6 to 13 ft); and microtidal coasts with a tidal range of less than 2 m (7 ft). The distinction between macrotidal and mesotidal coasts

4968-462: The whole ocean system are ultimately connected, although certain regional classifications are useful and relevant. The waters of the continental shelves represent such a region. The term "coastal waters" has been used in a wide variety of different ways in different contexts. In European Union environmental management it extends from the coast to just a few nautical miles while in the United States

5040-482: The world's people live in coastal regions. According to a United Nations atlas, 44% of all people live within 150 km (93 mi) of the sea. Many major cities are on or near good harbors and have port facilities. Some landlocked places have achieved port status by building canals . Nations defend their coasts against military invaders, smugglers and illegal migrants. Fixed coastal defenses have long been erected in many nations, and coastal countries typically have

5112-528: The world, where the live delicacy is harder to transport. Though some shellfish harvesting has been unsustainable, and shrimp farming has been destructive in some parts of the world, shellfish farming can be important to environmental restoration, by developing reefs, filtering water and eating biomass. The term "shellfish" is used both broadly and specifically. In common parlance, as in "having shellfish for dinner", it can refer to anything from clams and oysters to lobster and shrimp. For regulatory purposes it

5184-441: Was expanded upon by Benoit Mandelbrot . Tides often determine the range over which sediment is deposited or eroded. Areas with high tidal ranges allow waves to reach farther up the shore, and areas with lower tidal ranges produce deposition at a smaller elevation interval. The tidal range is influenced by the size and shape of the coastline. Tides do not typically cause erosion by themselves; however, tidal bores can erode as

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