Misplaced Pages

#47952

48-620: Chantuto people relied mainly on the diet of clams and fish. The sites that are linked to the Chantuto people hold the most evidence towards this theory as they consist of mainly clam shell remains, which have formed piles along five different lagoon archaeological sites. Chantuto culture was followed by the Barra culture and then the Mokaya people. In relation to the Chantuto people, five sites where located near lagoons that are conveniently positioned along

96-579: A New England clam bake . On the West Coast, they are an ingredient in making cioppino and local variants of ceviche . Clams are eaten more in the coastal regions of India, especially in the Konkan, Kerala , Bengal and coastal regions of Karnataka , Tamil Nadu regions. In Kerala , clams are used to make curries and fried with coconut. In the Malabar region it is known as "elambakka" and in middle kerala it

144-640: A siphon . Clams are shellfish that make up an important part of the web of life that keeps the seas functioning, both as filter feeders and as a food source for many different animals. Extant mammals that eat clams include both the Pacific and Atlantic species of walrus , all known subspecies of harbour seals in both the Atlantic and Pacific, most species of sea lions , including the California sea lion , bearded seals and even species of river otters that will consume

192-680: A canal where different shell middens have been discovered. Archaeologist Philip Drucker, who was one of the main participating archaeologists, dug a 2.5 meter test pit at one of the five Chantuto sites and discovered two different stratums, one containing a fair bit of pottery and one without any (Voorhies 2003). Most of the sites that were explored contained large amounts of shell deposits with limited to no other arte/eco facts. Other eco/artifacts in relation to these sites that have been found can include fish bones and other sea related goods. The archaeologists participating in these excavations, were able to date these sites “by means of radiocarbon assays and

240-572: A few other common edible species, such as the soft-shell clam , Mya arenaria , and the ocean quahog, Arctica islandica . Another species commercially exploited on the Atlantic Coast of the United States is the surf clam, Spisula solidissima . Scallops are also used for food nationwide, but not cockles : they are more difficult to get than in Europe because of their habit of being further out in

288-421: A hinge with a flexible ligament and all are filter feeders . A clam's shell consists of two (usually equal) valves, which are connected by a hinge joint and a ligament that can be internal or external. The ligament provides tension to bring the valves apart, whilst one or two adductor muscles can contract to close the valves. Clams also have kidneys, a heart, a mouth, a stomach, and a nervous system. Many have

336-470: A light beam through a column of water should be calibrated and reported in JTUs. The propensity of particles to scatter a light beam focused on them is now considered a more meaningful measure of turbidity in water. Turbidity measured this way uses an instrument called a nephelometer with the detector set up to the side of the light beam. More light reaches the detector if there are many small particles scattering

384-476: A number of chemical reagents that are available for treating turbidity. Reagents that are available for treating turbidity include aluminium sulfate or alum (Al 2 (SO 4 ) 3 ·nH 2 O), ferric chloride (FeCl 3 ), gypsum (CaSO 4 ·2H 2 O), poly- aluminium chloride , long chain acrylamide -based polymers and numerous proprietary reagents. The water chemistry must be carefully considered when chemical dosing as some reagents, such as alum, will alter

432-480: A reagent, generally a flocculant , evenly dispensed over the surface of the body of water. The flocs then settle at the bottom of the water body where they remain or are removed when the water body is drained. This method is commonly used at coal mines and coal loading facilities where stormwater collection ponds have seasonal issues with turbidity. A number of companies offer portable treatment systems for in-situ water treatment or direct dosing of reagents. There are

480-672: A slightly smaller cousin of the bamboo clam of eastern North America. These can be found for sale in open-air markets like Billingsgate Market in London; they have a similar taste to their North American cousin. Cockles, specifically the common cockle , are a staple find on beaches in western Wales and further north in the Dee Estuary . The accidentally introduced hard-shell quahog is also found in British waters, mainly those near England, and does see some use in British cuisine. The Palourde clam by far

528-400: A turbidity reading), a correlation between turbidity and total suspended solids (TSS) is somewhat unusual for each location or situation. Turbidity in lakes, reservoirs, channels, and the ocean can be measured using a Secchi disk . This black and white disk is lowered into the water until it can no longer be seen; the depth (Secchi depth) is then recorded as a measure of the transparency of

SECTION 10

#1732852869048

576-435: Is a common name for several kinds of bivalve mollusc . The word is often applied only to those that are edible and live as infauna , spending most of their lives halfway buried in the sand of the sea floor or riverbeds. Clams have two shells of equal size connected by two adductor muscles and have a powerful burrowing foot. They live in both freshwater and marine environments; in salt water they prefer to burrow down into

624-409: Is a key test of both water clarity and water quality . Fluids can contain suspended solid matter consisting of particles of many different sizes. While some suspended material will be large enough and heavy enough to settle rapidly to the bottom of the container if a liquid sample is left to stand (the settable solids ), very small particles will settle only very slowly or not at all if the sample

672-586: Is called marvai in the local Tulu language . It is used to prepare many dishes like marvai sukka , marvai gassi , and marvai pundi . In Japan, clams are often an ingredient of mixed seafood dishes. They can also be made into hot pot , miso soup or tsukudani . The more commonly used varieties of clams in Japanese cooking are the Shijimi ( Corbicula japonica ), the Asari ( Venerupis philippinarum ) and

720-459: Is commonly treated using a settling or filtration process, or both settling and filtration. Depending on the application, flocculants may be dosed into the water stream to increase the effectiveness of the settling or filtration process. Potable water treatment and municipal wastewater plants often remove turbidity with a combination of settling tanks, granular media filtration , and clarifiers . In-situ water treatment or direct dosing for

768-526: Is converted to a turbidity. Open source hardware has been developed following the ISO 7027 method to measure turbidity reliably using an Arduino microcontroller and inexpensive LEDs . There are several practical ways of checking water quality, the most direct being some measure of attenuation (that is, reduction in strength) of light as it passes through a sample column of water. The alternatively used Jackson Candle method (units: Jackson Turbidity Unit or JTU )

816-425: Is essentially the inverse measure of the length of a column of water needed to completely obscure a candle flame viewed through it. The more water needed (the longer the water column), the clearer the water. Of course water alone produces some attenuation, and any substances dissolved in the water that produce color can attenuate some wavelengths. Modern instruments do not use candles, but this approach of attenuation of

864-597: Is known as "kakka". Clam curry made with coconut is a dish from Malabar especially in the Thalassery region. On the southwestern coast of India , also known as the Konkan region of Maharashtra , clams are used in curries and side dishes, like Tisaryachi Ekshipi, which is clams with one shell on. Beary Muslim households in the Mangalore region prepare a main dish with clams called Kowldo Pinde. In Udupi and Mangalore regions, it

912-419: Is mostly widely used in Europe, whereas NTU is mostly widely used in the U.S. The ISO 7027 provides the method in water quality for the determination of turbidity. It is used to determine the concentration of suspended particles in a sample of water by measuring the incident light scattered at right angles from the sample. The scattered light is captured by a photodiode , which produces an electronic signal that

960-636: Is needed in order to support certain species, such as to protect juvenile fish from predators. For most mangroves along the eastern coast of Australia , in particular Moreton Bay , turbidity levels as high as 600 Nephelometric Turbidity Units (NTU) are needed for proper ecosystem health. The measurement of turbidity is a key test of both water clarity and water quality . There are two standard units for reporting turbidity: Formazin Nephelometric Units (FNU) from ISO 7027 and Nephelometric Turbidity Units (NTU) from USEPA Method 180.1. ISO 7027 and FNU

1008-997: Is regularly agitated or the particles are colloidal . These small solid particles cause the liquid to appear turbid. Turbidity (or haze) is also applied to transparent solids such as glass or plastic. In plastic production, haze is defined as the percentage of light that is deflected more than 2.5° from the incoming light direction. Turbidity in open water may be caused by growth of phytoplankton . Human activities that disturb land, such as construction , mining and agriculture , can lead to high sediment levels entering water bodies during rain storms due to storm water runoff . Areas prone to high bank erosion rates as well as urbanized areas also contribute large amounts of turbidity to nearby waters, through stormwater pollution from paved surfaces such as roads, bridges, parking lots and airports. Some industries such as quarrying , mining and coal recovery can generate very high levels of turbidity from colloidal rock particles. In drinking water,

SECTION 20

#1732852869048

1056-590: Is the most common native clam and it is both commercially harvested as well as locally collected, and Spisula solida , a relative of the Atlantic surf clam on the other side of the Atlantic, is seeing increased interest as a food source and aquaculture candidate; it is mainly found in the British Isles in Europe. In Italy, clams are often an ingredient of mixed seafood dishes or are eaten together with pasta. The more commonly used varieties of clams in Italian cooking are

1104-886: The vongola ( Venerupis decussata ) , the cozza (Mytilus galloprovincialis) and the tellina ( Donax trunculus ) . Though dattero di mare (Lithophaga lithophaga) was once eaten, overfishing drove it to the verge of extinction (it takes 15 to 35 years to reach adult size and could only be harvested by smashing the calcarean rocks that form its habitat) and the Italian government has declared it an endangered species since 1998 and its harvest and sale are forbidden. In Islam, clams are halal to eat as per three Sunni sects , but not in Hanafi, as only fish are considered halal in Hanafi jurisprudence , not other aquatic animals. In Judaism, clams are treif , i.e. non-kosher. Some species of clam, particularly Mercenaria mercenaria , were in

1152-742: The Chumash of California, the Nisqually of Washington state and the Tsawwassen of British Columbia . The butter clam, Saxidomus gigantea , the Pacific razor clam, Siliqua patula , gaper clams Tresus capax , the geoduck clam, Panopea generosa and the Pismo clam, Tivela stultorum are all eaten as delicacies. Clams can be eaten raw, steamed, boiled, baked or fried . They can also be made into clam chowder , clams casino , clam cakes , or stuffies , or they can be cooked using hot rocks and seaweed in

1200-461: The Hamaguri ( Meretrix lusoria ). The rocky terrain and pebbly shores of the seacoast that surrounds the entire island provide ample habitat for shellfish, and clams are most definitely included in that description. The oddity here is that for a nation whose fortunes have been tied to the sea for hundreds of years, 70% of the seafood cultivated for aquaculture or commercial harvesting is exported to

1248-534: The Chantuto period where located on the mainland side of each lagoon of this Estuary. These sites were described as round or oval in shape, containing various amounts of clam shells, which most likely where stored here by the Chantuto people (Voorhies 2003). All of these shell sites are located in the Acapetahua Estuary area. Archaeologists believe that the Chantuto people developed into the Barra people, and then into

1296-487: The Linke turbidity factor (T L ). Governments have set standards on the allowable turbidity in drinking water. In the United States, public water systems that use conventional or direct filtration methods must not have a turbidity higher than 1.0 NTU at the plant outlet and all samples for turbidity must be less than or equal to 0.3 NTU for at least 95 percent of the samples in any month. Systems that use filtration other than

1344-594: The Locona people. But according to John E. Clark , these were basically the same group of people, most likely speakers of proto-Mixe-Zoque, so he proposed the single term Mokaya to refer to them. The findings at this site are limited to a set of shell middens found along the lagoons of the Acapetahua Estuary, usually relating to clams. Voorhies proposes convincingly that the shell mound sites were mass procurement and processing stations for marsh dams that were dried and brought inland to base camp sites such as Vuelta Limon. At

1392-492: The amount of light reaching lower depths, which can inhibit growth of submerged aquatic plants and consequently affect species which are dependent on them, such as fish and shellfish . High turbidity levels can also affect the ability of fish gills to absorb dissolved oxygen. This phenomenon has been regularly observed throughout the Chesapeake Bay in the eastern United States. For many mangrove areas, high turbidity

1440-524: The bottom. An additional device, which may help measuring turbidity in shallow waters is the turbidity tube. The turbidity tube condenses water in a graded tube which allows determination of turbidity based on a contrast disk in its bottom, being analogous to the Secchi disk. Turbidity in air, which causes solar attenuation, is used as a measure of pollution. To model the attenuation of beam irradiance, several turbidity parameters have been introduced, including

1488-402: The catch than a generation ago, and there is a prevalence of YouTube videos of locavore scavenging. Shellfish have provided a staple of the British diet since the earliest occupations of the British Isles, as evidenced by the large numbers of remains found in midden mounds near occupied sites. Staple favourites of the British public and local scavengers include the razorfish, Ensis siliqua ,

Chantuto Archaeological Site - Misplaced Pages Continue

1536-520: The continent. Historically, Britain has been an island most famous for its passion for beef and dairy products, although there is evidence going back to before most recorded history of coastal shell middens near Weymouth and present day York. (There is also evidence of more thriving local trade in sea products in general by noting the Worshipful Company of Fishmongers was founded in 1272 in London.) Present-day younger populations are eating more of

1584-689: The conventional or direct filtration must follow state limits, which must include turbidity at no time exceeding 5 NTU. Many drinking water utilities strive to achieve levels as low as 0.1 NTU. The European turbidity standard is 4 NTU. The US Environmental Protection Agency (EPA) has published water quality criteria for turbidity. These criteria are scientific assessments of the effects of turbidity, which are used by states to develop water quality standards for water bodies. (States may also publish their own criteria.) Some states have promulgated water quality standards for turbidity, including: Published analytical test methods for turbidity include: Turbidity

1632-410: The discussed Chantuto phase sites such as Vuelta Limon and Tlachuachero (Hirst 2010). Drucker explored the shell mound of Islona Chantuto. His excavations lead to him being convinced that this site was more than likely a pre-ceramic age and decided to discover it further. Later Voorhies worked to understand and evaluate the Chantuto sites and the people who inhabited this area. Clams Clam

1680-619: The freshwater species found in Asia and North America. Birds of all kinds will also eat clams if they can catch them in the littoral zone : roseate spoonbills of North and South America, the Eurasian oystercatcher , whooping crane and common crane , the American flamingo of Florida and the Caribbean Sea, and the common sandpiper are just a handful of the numerous birds that feast on clams all over

1728-586: The higher the turbidity level, the higher the risk that people may develop gastrointestinal diseases . This is especially problematic for immunocompromised people, because contaminants like viruses or bacteria can become attached to the suspended solids. The suspended solids interfere with water disinfection with chlorine because the particles act as shields for viruses and bacteria. Similarly, suspended solids can protect bacteria from ultraviolet (UV) sterilization of water. In water bodies such as lakes , rivers and reservoirs , high turbidity levels can reduce

1776-571: The main archaeologist behind studying this Chantuto site and the people who inhabited this area. Barbara Voorhies is an American archaeologist who was educated at Tufts and Yale University. Voorhies has also taught at the University of Colorado and the University of California in Santa Barbara for nearly thirty years (Hirst 2010). She is recognized for her work with the shell mound archaic sites of coastal Mexico, such as Cerro de las Conchas, Chiapas, and

1824-459: The methods of data recovery and interpretation ranging from replication experiments to ethnographic analogy", which helped date these sites between 3,500-7,500 years of age. Archaeologists exploring the Chantuto people and their gathering habits have found and excavated five different archaeological sites that have been referred to by archaeologist Barbara Voorhies as the “five coastal lagoons" (Voorhies 2003). The shell mound sites that are related to

1872-822: The mud and the turbidity of the water required varies with species and location; the greatest diversity of these is in North America . Clams in the culinary sense do not live attached to a substrate (whereas oysters and mussels do) and do not live near the bottom (whereas scallops do). In culinary usage, clams are commonly eaten marine bivalves, as in clam digging and the resulting soup, clam chowder . Many edible clams such as palourde clams are ovoid or triangular; however razor clams have an elongated parallel-sided shell, suggesting an old-fashioned straight razor. Some clams have life cycles of only one year, whilst at least one has been aged to more than 500 years. All clams have two calcareous shells or valves joined near

1920-473: The past used by the Algonquians of Eastern North America to manufacture wampum , a type of sacred jewellery ; and to make shell money . Edible: Not usually considered edible: Turbidity Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye , similar to smoke in air . The measurement of turbidity

1968-444: The sand very close to the beach, it cannot be harvested by mechanical means without damaging the beaches. The bamboo clam is also notorious for having a very sharp edge of its shell, and when harvested by hand must be handled with great care. On the U.S. West Coast, there are several species that have been consumed for thousands of years, evidenced by middens full of clamshells near the shore and their consumption by nations including

Chantuto Archaeological Site - Misplaced Pages Continue

2016-527: The site of Tlachuachero, out of 17 samples taken from this stratum, such objects as bone, ceramics, shell, rock fragments and clay nodules arose. The collection results from this site outlined that 99.55% of the total weight of the samples were made up of clam shells with the remainder as other items, such as fish bone for example. At the other four archaeological sites there have been a small amount of different objects found, such as but not limited to metates, hand stones, and anvils. Barbara Voorhies can be seen as

2064-416: The source beam than if there are few. The units of turbidity from a calibrated nephelometer can be either NTU or FTU, depending on the standard method used. To some extent, how much light reflects for a given amount of particulates is dependent upon properties of the particles like their shape, color, and reflectivity. For this reason (and the reason that heavier particles settle quickly and do not contribute to

2112-594: The strawberry cockle; and Dinocardium robustum , which grows to be many times the size of the European cockle. Historically, they were caught on a small scale on the Outer Banks , barrier islands off North Carolina, and put in soups, steamed or pickled. Up and down the coast of the Eastern U.S., the bamboo clam , Ensis directus , is prized by Americans for making clam strips , although because of its nature of burrowing into

2160-535: The tide than European species on the West Coast, and on the East Coast they are often found in salt marshes and mudflats where mosquitoes are abundant. There are several edible species in the Eastern United States: Americardia media , also known as the strawberry cockle, is found from Cape Hatteras down into the Caribbean Sea and all of Florida; Trachycardium muricatum has a similar range to

2208-414: The treatment of turbidity is common when the affected water bodies are dispersed (i.e. there are numerous water bodies spread out over a geographical area, such as small drinking water reservoirs), when the problem is not consistent (i.e. when there is turbidity in a water body only during and after the wet season) or when a low cost solution is required. In-situ treatment of turbidity involves the addition of

2256-453: The water (inversely related to turbidity). The Secchi disk has the advantages of integrating turbidity over depth (where variable turbidity layers are present), being quick and easy to use, and inexpensive. It can provide a rough indication of the depth of the euphotic zone with a 3-fold division of the Secchi depth , however this cannot be used in shallow waters where the disk can still be seen on

2304-541: The world. Most species of octopus have clams as a staple of their diet, up to and including the giants like the Giant Pacific octopus . Cultures around the world eat clams along with many other types of shellfish. In culinary use, within the eastern coast of the United States and large swathes of the Maritimes of Canada, the term "clam" most often refers to the hard clam , Mercenaria mercenaria . It may also refer to

#47952