Juncus roemerianus | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Clade: | Commelinids |
Order: | Poales |
Family: | Juncaceae |
Genus: | Juncus |
Species: | J. roemerianus |
Binomial name | |
Juncus roemerianus Scheele | |
Juncus roemerianus is a species of flowering plant in the rush family known by the common names black rush, needlerush, and black needlerush. It is native to North America, where its main distribution lies along the coastline of the southeastern United States, including the Gulf Coast. It occurs from New Jersey to Texas, with outlying populations in Connecticut, New York, Mexico, and certain Caribbean islands. [1]
This rush is a perennial plant forming tufts of rough, rigid stems and leaves. It is gray-green in color. The plant may appear to be leafless at first glance, but what look like sharp-pointed stems are actually stiff leaves rolled tightly to form pointed cylinders. The true stems are tipped with inflorescences. [2] It grows from a rhizome. This plant is variable in appearance. Its size and shape depend on environmental conditions in its salt marsh habitat. In areas with low soil salinity the plant can exceed two meters in height, whereas in high-salinity areas the rush is dwarfed, sometimes measuring under 30 centimeters (12 in.) tall. Both large and small plants generally occur in one marsh, with the large plants nearest the open water and the small plants occurring on higher ground in the salt flats and other areas of higher salinity. [1] Plants of different sizes differ genetically, as well, with soil salinity being the selective force leading to the genetic variation. The dwarf plants have an adaptation to high soil salinity. Larger plants lack this adaptation, and do not survive when experimentally transplanted to high-salinity environments. [3]
The plant reproduces sexually by seed and vegetatively by sprouting from its spreading rhizome. It expands its dense, sometimes monotypic stands by sending up new stems from the rhizome, and establishes new stands by broadcasting seeds. The species is gynodioecious, with some plants having bisexual flowers and some having only female reproductive parts. The seeds are very viable, germinating readily, but they require light for germination and may fail to sprout if covered in thick mud. Therefore, seedlings are most often seen in open, sandy stretches, and rarely in areas with dense vegetation or thick substrates. The plant grows new shoots and leaves year-round, and does not typically experience seasonal growth spurts. [1] Dead leaves remain on the plant for a long time, leading to an accumulation of plant matter. The species may form much of the physical structure of the marsh. [4]
This is a common and ecologically important plant in its range, often dominating salt marshes and estuaries. In northwestern Florida perhaps 60% of all the salt marshes are covered in this species of rush. This species and smooth cordgrass (Spartina alterniflora) are the dominant plants in Mississippi tidal marshes. [5] These two species are often found together, [6] with S. alterniflora occupying lower levels of the marsh and J. roemerianus growing in the mid-level and upper reaches of the marsh. [7] In river estuaries it can occur 10 to 15 miles inland. [1]
Other plants occurring in the higher-salinity regions of the marsh include saltmeadow cordgrass (S. patens), giant cordgrass (S. cynosuroides), saltgrass (Distichlis spicata), glassworts (Salicornia spp.), Olney threesquare (Scirpus americanus), and saltmarsh bulrush (Scirpus robustus). In the brackish marsh plant associates may include sealavender (Limonium carolinianum) and common arrowhead (Sagittaria latifolia). In the intermediate marsh between the brackish and freshwater marsh levels other plants include common reed (Phragmites australis), sawgrass (Cladium jamaicense), softstem bulrush (Scirpus validus), and Virginia iris (Iris virginica). [1]
This rush provides cover for a number of salt marsh animal species. Birds such as the long-billed marsh wren, clapper rail, and seaside sparrow nest in it. Rice rats nest in it and prey on the eggs of the local birds. A number of fungal species grow on this rush, some exclusively. The new ascomycete species Aquamarina speciosa , Keissleriella rara , Massarina carolinensis , and Paraphaeosphaeria pilleata were described from dead or dying stems of this rush. [8] Also fungus Juncigena adarca ( Juncigenaceae , Torpedosporales) was only found on the senescent leaves (decaying leaves) of Juncus roemerianus, [8] [9] on the Atlantic coast (U.S.A.: North Carolina). [10]
This plant has shown potential as an agent of phytoremediation after oil spills. When it grows in sediments polluted with diesel fuel it reduces the concentration of total petroleum hydrocarbons, polycyclic aromatic hydrocarbons, and n-alkanes in the sediments. [11]
Juncusol is a 9,10-dihydrophenathrene derivative found in J. roemerianus. [12] [13]
A halophyte is a salt-tolerant plant that grows in soil or waters of high salinity, coming into contact with saline water through its roots or by salt spray, such as in saline semi-deserts, mangrove swamps, marshes and sloughs and seashores. The word derives from Ancient Greek ἅλας (halas) 'salt' and φυτόν (phyton) 'plant'. Halophytes have different anatomy, physiology and biochemistry than glycophytes. An example of a halophyte is the salt marsh grass Spartina alterniflora. Relatively few plant species are halophytes—perhaps only 2% of all plant species. Information about many of the earth's halophytes can be found in the ehaloph database.
A salt marsh, saltmarsh or salting, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is dominated by dense stands of salt-tolerant plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh in trapping and binding sediments. Salt marshes play a large role in the aquatic food web and the delivery of nutrients to coastal waters. They also support terrestrial animals and provide coastal protection.
Scirpus is a genus of grass-like species in the sedge family Cyperaceae many with the common names club-rush, wood club-rush or bulrush. They mostly inhabit wetlands and damp locations.
Sporobolus alterniflorus, or synonymously known as Spartina alterniflora, the smooth cordgrass, saltmarsh cordgrass, or salt-water cordgrass, is a perennial deciduous grass which is found in intertidal wetlands, especially estuarine salt marshes. It has been reclassified as Sporobolus alterniflorus after a taxonomic revision in 2014, but it is still common to see Spartina alterniflora and in 2019 an interdisciplinary team of experts coauthored a report published in the journal Ecology supporting Spartina as a genus. It grows 1–1.5 m tall and has smooth, hollow stems that bear leaves up to 20–60 cm long and 1.5 cm wide at their base, which are sharply tapered and bend down at their tips. Like its relative saltmeadow cordgrass S. patens, it produces flowers and seeds on only one side of the stalk. The flowers are a yellowish-green, turning brown by the winter. It has rhizoidal roots, which, when broken off, can result in vegetative asexual growth. The roots are an important food resource for snow geese. It can grow in low marsh as well as high marsh, but it is usually restricted to low marsh because it is outcompeted by salt meadow cordgrass in the high marsh. It grows in a wide range of salinities, from about 5 psu to marine, and has been described as the "single most important marsh plant species in the estuary" of Chesapeake Bay. It is described as intolerant of shade.
Ecological facilitation or probiosis describes species interactions that benefit at least one of the participants and cause harm to neither. Facilitations can be categorized as mutualisms, in which both species benefit, or commensalisms, in which one species benefits and the other is unaffected. This article addresses both the mechanisms of facilitation and the increasing information available concerning the impacts of facilitation on community ecology.
Brackish marshes develop from salt marshes where a significant freshwater influx dilutes the seawater to brackish levels of salinity. This commonly happens upstream from salt marshes by estuaries of coastal rivers or near the mouths of coastal rivers with heavy freshwater discharges in the conditions of low tidal ranges.
Aquamarina is a fungal genus in the class Dothideomycetes. It is a monotypic genus, containing the single marine species Aquamarina speciosa, originally found in North Carolina, and distributed in the Atlantic Coast of the United States. The bluish-green species fruits exclusively in the lower parts of dying culms of the saltmarsh plant Juncus roemerianus.
Juncus kraussii commonly known as salt marsh rush, sea rush, jointed rush, matting rush or dune slack rush, is of the monocot family Juncaceae and genus Juncus. It grows in salt marshes, estuarine and coastal areas.
Sporobolus michauxianus is a species of cordgrass known as prairie cordgrass, freshwater cordgrass, tall marshgrass, and sloughgrass. It is native to much of North America, including central and eastern Canada and most of the contiguous United States except for the southwestern and southeastern regions. Its distribution extends into Mexico. It is also present on other continents as an introduced species.
Schoenoplectus americanus is a species of flowering plant in the sedge family known by the common names chairmaker's bulrush and Olney's three-square bulrush. It is native to the Americas, where it is known from Alaska to Nova Scotia and all the way into southern South America; it is most common along the East and Gulf Coasts of the United States and in parts of the western states. It grows in many types of coastal and inland wetland habitat, as well as sagebrush, desert scrub, chaparral, and plains. This rhizomatous perennial herb easily exceeds two meters in height. The stiff stems are sharply three-angled and usually very concave between the edges. Each plant has three or fewer leaves which are short and narrow. The inflorescence is a small head of several spikelets which may be brown to bright orange, red, purplish, or pale and translucent. They have hairy edges. The fruit is a brown achene. The plant reproduces sexually by seed and colonies spread via vegetative reproduction, sprouting from the rhizomes.
Salt pannes and pools are water retaining depressions located within salt and brackish marshes. Pools tend to retain water during the summer months between high tides, whereas pannes generally do not. Salt pannes generally start when a mat of organic debris is deposited upon existing vegetation, killing it. This creates a slight depression in the surrounding vegetation which retains water for varying periods of time. Upon successive cycles of inundation and evaporation the panne develops an increased salinity greater than that of the larger body of water. This increased salinity dictates the type of flora and fauna able to grow within the panne. Salt pools are also secondary formations, though the exact mechanism(s) of formation are not well understood; some have predicted they will increase in size and abundance in the future due to rising sea levels.
Sporobolus montevidensis is a species of grass known by the common name denseflower cordgrass. Although reclassified after a taxonomic revision in 2014, it may still be referred to as Spartina densiflora by some users. It is native to the coastline of southern South America, where it is a resident of salt marshes. It is also known on the west coast of the North America and parts of the Mediterranean coast as an introduced species and in some areas a noxious weed. In California it is a troublesome invasive species of marshes in San Francisco Bay and in Humboldt Bay, where it was introduced during the 19th century from Chile in ballast.
Sporobolus foliosus is a species of grass known by the common name California cordgrass. It was reclassified from Spartina foliosa after a taxonomic revision in 2014. It is native to the salt marshes and mudflats of coastal California and Baja California, especially San Francisco Bay. It is a perennial grass growing from short rhizomes. It produces single stems or clumps of thick, fleshy stems that grow up to 1.5 meters tall. They are green or purple-tinged. The long, narrow leaves are flat or rolled inward. The inflorescence is a narrow, dense, spike-like stick of branches appressed together, the unit reaching up to 25 centimeters long. The lower spikelets are sometimes enclosed in the basal sheaths of upper leaves.
Sporobolus pumilus, the saltmeadow cordgrass, also known as salt hay, is a species of cordgrass native to the Atlantic coast of the Americas, from Newfoundland south along the eastern United States to the Caribbean and north-eastern Mexico. It was reclassified after a taxonomic revision in 2014, but the older name, Spartina patens, may still be found in use. It can be found in marshlands in other areas of the world as an introduced species and often a harmful noxious weed or invasive species.
Scirpus ancistrochaetus is a rare species of flowering plant in the sedge family known by the common names barbedbristle bulrush and northeastern bulrush. It is native to the northeastern United States from New Hampshire south to Virginia. It used to be found in Quebec but it is now thought to be extirpated there. It was also believed extirpated from the state of New York, but at least one population has been rediscovered in Steuben County in 2010. It is threatened by the loss and degradation of its wetland habitat. It is a federally listed endangered species.
Massarina carolinensis is a species of fungus in the Lophiostomataceae family. The species is found exclusively on the lower parts of the culms of the saltmarsh Juncus roemerianus on the Atlantic Coast of North Carolina.
Paraphaeosphaeria pilleata is a species of fungus in the Lophiostomataceae family. The species fruits exclusively in the lower parts of the culms of the black needlerush. It is found on the Atlantic Coast of North Carolina.
Sporobolus cynosuroides is a species of grass known by the common names big cordgrass and salt reedgrass. It is native to the East Coast and Gulf Coast of the United States, where it grows in coastal habitat such as marshes, lagoons, and bays.
Sporobolus spartinae is a species of grass known by the common names gulf cordgrass and sacahuista. It is native to the Americas, where it occurs from the Gulf Coast of the United States south to Argentina.
Salt marsh die-off is a term that has been used in the US and UK to describe the death of salt marsh cordgrass leading to subsequent degradation of habitat, specifically in the low marsh zones of salt marshes on the coasts of the Western Atlantic. Cordgrass normally anchors sediment in salt marshes; its loss leads to decreased substrate hardness, increased erosion, and collapse of creek banks into the water, ultimately resulting in decreased marsh health and productivity.