Ammophila | |
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European marram grass Dunes near The Hague, February | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Clade: | Commelinids |
Order: | Poales |
Family: | Poaceae |
Genus: | Ammophila Host [1] |
Species | |
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The range of Ammophila in North America |
Ammophila (synonymous with Psamma P. Beauv.) is a genus of flowering plants consisting of two or three very similar species of grasses. The common names for these grasses include marram grass, bent grass, and beachgrass. [2] These grasses are found almost exclusively on the first line of coastal sand dunes. Their extensive systems of creeping underground stems or rhizomes allow them to thrive under conditions of shifting sands and high winds, and to help stabilize and prevent coastal erosion. Ammophila species are native to the coasts of the North Atlantic Ocean where they are usually the dominant species on sand dunes. Their native range includes few inland regions, with the Great Lakes of North America being the main exception. [3] The genus name Ammophila originates from the Greek words ἄμμος (ámmos), meaning "sand", and φίλος (philos), meaning "friend".
The Ammophila grasses are widely known as examples of xerophytes, plants that can withstand dry conditions. Despite their occurrence on seacoasts, Ammophila grasses are not particularly tolerant of saline soils; they can tolerate a salinity of about 15 g/L (1.5%), which makes them "moderate halophytes". [4]
Ammophila builds coastal sand dunes and thus stabilizes the sand. For this reason, the plants are seen as a useful means of reinforcing sand dunes around the world, and have been introduced far from their native range. Alfred Wiedemann writes that Ammophila arenaria , the European species, "has been introduced into virtually every British colonial settlement within its latitudinal tolerance range, including southeast and southwest Australia, New Zealand, South Africa, the Falkland Islands, and Norfolk Island and has been reported from Argentina and Chile." [5] Ammophila species were introduced in the late 19th century on the Pacific coast of North America as well, and massive, intentional plantings were continued at least through 1960. In essentially all of the locations where they have been introduced, Ammophila plants are now listed as invasive, and costly efforts are underway to eradicate them.[ citation needed ]
Only two species seem incontrovertible: A. arenaria and A. breviligulata. Two other species have been proposed, and are discussed below.
In Europe, Ammophila arenaria has a coastal distribution, and is the dominant species on sand dunes where it is responsible for stabilising and building the foredune by capturing blown sand and binding it together with the warp and weft of its tough, fibrous rhizome system. Marram grass is strongly associated with two coastal plant community types in the British National Vegetation Classification. In community SD6 (Mobile dune) Ammophila is the dominant species. In the semi-fixed dunes (community SD7), where the quantity of blown sand is declining Ammophila becomes less competitive, and other species, notably Festuca rubra (red fescue) become prominent.
The ability of marram grass to grow on and bind sand makes it a useful plant in the stabilization of coastal dunes and artificial defences on sandy coasts. The usefulness was recognized in the late 18th century. [10] [11] On the North Sea coast of Jutland, Denmark, marram grass was traditionally much used for fuel, thatch, cattle fodder (after frost) etc. The use led to sand drift and loss of arable land. Hence, legislation promoting dune stabilization came into force in 1779 and 1792, successively leading to a system of state-supported dune planters overlooked by dune bailiffs. Marram grass was – and still is – propagated by root and shoot cuttings dug up locally and planted into the naked sand in periods of relatively calm and moist weather.
Women from the village of Newborough, Anglesey, Wales once used marram grass in the manufacture of mats, haystack covers and brushes for whitewashing.
Marram grass has been widely used for thatch in many areas of the British Isles close to the sea. The harvesting of marram grass for thatch was so widespread during the 17th century that it had the effect of destabilizing dunes, resulting in the burial of many villages, estates and farms. In 1695 the practice was banned by an Act of the Scottish Parliament: [12]
Considering that many lands, meadowes and pasturages lying on sea coasts have been ruined and overspread in many places in this kingdom by sand driven from adjacent sand hills ... His Majesty does strictly prohibit and discharge the pulling of bent, broom or juniper off the sand hills for hereafter.
Like other xerophytes, marram grass is well adapted to its surroundings in order to thrive in an otherwise harsh environment. The natural loss of water through transpiration is not desirable in a very dry landscape, and marram grass has developed particular adaptations to help it deal with this. Sandy conditions drain water quickly, and very windy conditions will further increase rates of transpiration.
Marram grass has a rolled leaf that creates a localized environment of water vapour concentration within the leaf, and helps to prevent water loss. The stomata sit in small pits within the curls of the structure, which make them less likely to open and to lose water. The folded leaves have hairs on the inside to slow or stop air movement, much like many other xerophytes (though these are typically found on the outside of the plant, but in marram grass they are also within the leaf as this has now become a structure with more volume). This slowing of air movement once again reduces the amount of water vapour being lost. A waxy cuticle on the leaf surface also prevents evaporation.
Southwick Beach State Park is a New York State park that lies along an unusual stretch of sandy beach on the eastern shore of Lake Ontario. The park is 464 acres (188 ha) in size with a 3,500 foot (1,100 m) length of beach, and is visited annually by about 100,000 people. Immediately to the south is the Lakeview Wildlife Management Area, which extends the publicly accessible beach by several miles. They are in the Town of Ellisburg in Jefferson County, New York south of the lakeside community of Jefferson Park.
The Oregon Dunes National Recreation Area is located on the Oregon Coast, stretching approximately 40 miles (64 km) north of the Coos River in North Bend to the Siuslaw River in Florence, and adjoining Honeyman State Park on the west. It is part of Siuslaw National Forest and is administered by the United States Forest Service.
NVC community SD11 is one of the 16 sand-dune communities in the British National Vegetation Classification system.
Uniola paniculata, also known as sea oats, seaside oats, araña, and arroz de costa, is a tall subtropical grass that is an important component of coastal sand dune and beach plant communities in the southeastern United States, eastern Mexico and some Caribbean islands.
Ammophila arenaria is a species of grass in the family Poaceae. It is known by the common names marram grass and European beachgrass. It is one of two species of the genus Ammophila. It is native to the coastlines of Europe and North Africa where it grows in the sands of beach dunes. It is a perennial grass forming stiff, hardy clumps of erect stems up to 1.2 metres (3.9 ft) in height. It grows from a network of thick rhizomes which give it a sturdy anchor in its sand substrate and allow it to spread upward as sand accumulates. These rhizomes can grow laterally by 2 metres in six months. One clump can produce 100 new shoots annually.
Tuckernuck is an island in the town and former whaling port of Nantucket, Massachusetts, west of Nantucket Island and east of Muskeget Island. Its name allegedly means "a loaf of bread". The island has an area of about 900 acres. The highest point is about 50 feet (15 m).
Sand dune ecology describes the biological and physico-chemical interactions that are a characteristic of sand dunes.
Ammophila breviligulata is a species of grass native to eastern North America, where it grows on sand dunes along the Atlantic Ocean and Great Lakes coasts. Beachgrass thrives under conditions of shifting sand, sand burial, and high winds; it is a dune-building grass that builds the first line of sand dunes along the coast. Beachgrass is less vigorous in stabilized sand, and is only infrequently found further inland than the coastal foredunes. On the Atlantic coastline of North America, Ammophila breviligulata has been observed as far south as North Carolina, and is often planted in dune restoration projects. Ammophila breviligulata was introduced to the Pacific coast of North America in the 1930s. It is proving to be invasive, and is increasingly important to coastal ecology and development in Oregon, Washington, and British Columbia.
NVC community SD12 is one of the 16 sand-dune communities in the British National Vegetation Classification system.
NVC community SD19 is one of the 16 sand-dune communities in the British National Vegetation Classification system. It is one of six communities associated with foredunes and mobile dunes.
Sand dune stabilization is a coastal management practice designed to prevent erosion of sand dunes. Sand dunes are common features of shoreline and desert environments. Dunes provide habitat for highly specialized plants and animals, including rare and endangered species. They can protect beaches from erosion and recruit sand to eroded beaches. Dunes are threatened by human activity, both intentional and unintentional. Countries such as the United States, Australia, Canada, New Zealand, the United Kingdom, and Netherlands, operate significant dune protection programs.
A xerophyte is a species of plant that has adaptations to survive in an environment with little liquid water. Examples of xerophytes include cacti, pineapple and some gymnosperm plants. The morphology and physiology of xerophytes are adapted to conserve water during dry periods. Some species called resurrection plants can survive long periods of extreme dryness or desiccation of their tissues, during which their metabolic activity may effectively shut down. Plants with such morphological and physiological adaptations are said to be xeromorphic. Xerophytes such as cacti are capable of withstanding extended periods of dry conditions as they have deep-spreading roots and capacity to store water. Their waxy, thorny leaves prevent loss of moisture.
Chorizanthe howellii is a species of flowering plant in the buckwheat family known by the common names Mendocino spineflower and Howell's spineflower. It is endemic to coastal Mendocino County, California, where it is known only from the sand dunes and coastal scrub near Fort Bragg. It is estimated that 95% of the remaining individuals of this plant are part of a single population growing at MacKerricher State Park. It is a federally listed endangered species.
Phacelia argentea is a rare species of phacelia known by the common names sand dune phacelia and silvery phacelia. It is native to the coastline of southwestern Oregon and far northwestern California, where it was counted at a total of 33 sites in 1995. It is the only phacelia species endemic to coastal sand dune habitat, an ecosystem which is altered and declining in the area.
A. arenaria may refer to:
A foredune is a dune ridge that runs parallel to the shore of an ocean, lake, bay, or estuary. Foredunes consist of sand deposited by wind on a vegetated part of the shore. Foredunes can be classified generally as incipient or established.
Psathyrella ammophila is a species of fungus in the family Psathyrellaceae and is found throughout Europe. Commonly known as the dune brittlestem, this agaric primarily grows on sand dunes near marram grass, feeding saprotrophically on the decaying roots. The season of growth is generally May to November.
Leccinum arenicola is a species of bolete mushroom in the family Boletaceae. Described in 1979, the fruit bodies (mushrooms) grow in sand dunes from New Brunswick south to Cape Cod.
Leymus mollis is a species of grass known by the common names American dune grass, American dune wild-rye, sea lyme-grass, strand-wheat, and strand grass. Its Japanese name is hamaninniku. It is native to Asia, where it occurs in Japan, China, Korea, and Russia, and northern parts of North America, where it occurs across Canada and the northern United States, as well as Greenland. It can also be found in Iceland.
The Cresmina Dune extends over 66 hectares and is a part of the Guincho-Oitavos dune system, located on the edge of the Sintra-Cascais Natural Park near Cascais in Portugal. This dune system is considered fairly unique because, as a result of the prevailing northwest winds, the sand from the Guincho and Cresmina beaches eventually returns to the sea 5 km further to the south near Guia, after migrating over the flat, rocky and largely uninhabited area of Cabo Raso.