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Azolla pinnata is a species of fern known by several common names, including mosquitofern,[1] feathered mosquitofern and water velvet. It is native to much of Africa, Asia (Brunei Darussalam, China, India, Japan, Korea, and the Philippines) and parts of Australia. It is an aquatic plant, it is found floating upon the surface of the water. It grows in quiet and slow-moving water bodies because swift currents and waves break up the plant.[2] At maximum growth rate, it can double its biomass in 1.9 days, with most strains attaining such growth within a week under optimal conditions.[3]
A. pinnata is a small fern with a triangular stem measuring up to 2.5 centimeters in length that floats on the water. The stem bears many rounded or angular overlapping leaves each 1 or 2 millimeters long. They are green, blue-green, or dark red in color and coated in tiny hairs, giving them a velvety appearance.[2] The hairs make the top surface of the leaf water-repellent, keeping the plant afloat even after being pushed under.[2] A water body may be coated in a dense layer of the plants, which form a velvety mat that crowds out other plants.[2] The hairlike roots extend out into the water.[2] The leaves contain the cyanobacterium Anabaena azollae, which is a symbiont that fixes nitrogen from the atmosphere that the fern can use.[2][4] This gives the fern the ability to grow in habitats that are low in nitrogen.[4]
The plant reproduces vegetatively when branches break off the main axis, or sexually when sporocarps on the leaves release spores.[5]
It is present in New Zealand as an introduced species and an invasive weed that has crowded out a native relative, Azolla rubra.[2] It is a pest of waterways because its dense mats reduce oxygen in the water.[6] The weevil Stenopelmus rufinasus is used as an agent of biological pest control to manage Azolla filiculoides, and it has been found to attack A. pinnata as well.[7]
Rice farmers sometimes keep this plant in their paddies because it generates valuable nitrogen via its symbiotic cyanobacteria.[2][5] The plant can be grown in wet soil and then plowed under, generating a good amount of nitrogen-rich fertilizer.[8] The plant has the ability to absorb a certain amount of heavy metal pollution, such as lead, from contaminated water.[9] It is 25-30% protein and can be added to chicken feed.[10][11]
Recent studies show the usefulness of Azolla pinnata in the remediation of environmental pollutants. There are two main methods for utilising A. pinnata to clean up environmental pollutants. The first method is by adsorption, which required the A. pinnata fronds to be processed into powder and agitated with the wastewater for a fixed duration. The pollutant will adhere to the organic functional groups on the surface of the A. pinnata powder. In adsorption studies, A. pinnata was reported in the remediation of dye wastewater containing methyl violet 2B,[12] malachite green,[13] rhodamine B,[14] acid red 88[15] and acid blue 25.[16]
The second remediation method is phytoremediation, where living A. pinnata is suspended on the surface of the wastewater. A. pinnata was primarily studied due to its high tolerance to environmental pollutants, and ability to hyperaccumulate heavy metals.[17] Phytoremediation of industrial wastewater containing heavy metals (such as zinc, lead,[18] chromium,[19] mercury, cadmium,[20] copper, arsenic[17]) as well as organic dyes such as methyl violet 2B[21] and malachite green[22] are reported in literature. A.pinnata is also reported to be useful for treating the wastewater (remove nitrogenous waste and phosphorus) of poultry farms.[23]
Azolla pinnata is a species of fern known by several common names, including mosquitofern, feathered mosquitofern and water velvet. It is native to much of Africa, Asia (Brunei Darussalam, China, India, Japan, Korea, and the Philippines) and parts of Australia. It is an aquatic plant, it is found floating upon the surface of the water. It grows in quiet and slow-moving water bodies because swift currents and waves break up the plant. At maximum growth rate, it can double its biomass in 1.9 days, with most strains attaining such growth within a week under optimal conditions.
A. pinnata is a small fern with a triangular stem measuring up to 2.5 centimeters in length that floats on the water. The stem bears many rounded or angular overlapping leaves each 1 or 2 millimeters long. They are green, blue-green, or dark red in color and coated in tiny hairs, giving them a velvety appearance. The hairs make the top surface of the leaf water-repellent, keeping the plant afloat even after being pushed under. A water body may be coated in a dense layer of the plants, which form a velvety mat that crowds out other plants. The hairlike roots extend out into the water. The leaves contain the cyanobacterium Anabaena azollae, which is a symbiont that fixes nitrogen from the atmosphere that the fern can use. This gives the fern the ability to grow in habitats that are low in nitrogen.
The plant reproduces vegetatively when branches break off the main axis, or sexually when sporocarps on the leaves release spores.
It is present in New Zealand as an introduced species and an invasive weed that has crowded out a native relative, Azolla rubra. It is a pest of waterways because its dense mats reduce oxygen in the water. The weevil Stenopelmus rufinasus is used as an agent of biological pest control to manage Azolla filiculoides, and it has been found to attack A. pinnata as well.
Rice farmers sometimes keep this plant in their paddies because it generates valuable nitrogen via its symbiotic cyanobacteria. The plant can be grown in wet soil and then plowed under, generating a good amount of nitrogen-rich fertilizer. The plant has the ability to absorb a certain amount of heavy metal pollution, such as lead, from contaminated water. It is 25-30% protein and can be added to chicken feed.
Azolla pinnata est une petite fougère aquatique flottante originaire du sud-est asiatique à l'Afrique de l'Est. Elle appartient à la famille des Salviniaceae (ou des Azollaceae selon les classifications).
Elle coexiste souvent avec des lentilles d'eau (ou lenticules), autres plantes aquatiques flottantes du genre Lemna (famille des Araceae, auparavant des Lemnaceae). Elle est considérée comme " plante envahissante ".
Ces plantes ont un appareil végétatif leur permettant de flotter à la surface de l'eau, dans l'atmosphère et dans l'eau via un réseau de racines filiformes. Dans les eaux douces stagnantes et tiédies par le soleil d’été, ces Azolla forment des noyaux de populations qui par bourgeonnement s’étendent et croissent jusqu’à recouvrir la totalité d’un plan d’eau. Elles peuvent former un tapis d'un à deux centimètres d'épaisseur ne laissant plus passer la lumière. Elles sont alors une cause d'anoxie, lorsqu'elles meurent toutes ensemble en hiver dans les zones froides.
Azolla pinnata gagne du terrain sur tous les continents y compris en Australie. Présentes en grande quantité, elles sont un des signes possibles d'eutrophisation.
Elle abrite dans son feuillage une cyanobactérie (Anabaena azollae) qui fixe pour elle l'azote. C'est pourquoi cette fougère est parfois utilisée comme engrais biologique dans les rizières.
Azolla pinnata est une petite fougère aquatique flottante originaire du sud-est asiatique à l'Afrique de l'Est. Elle appartient à la famille des Salviniaceae (ou des Azollaceae selon les classifications).
Elle coexiste souvent avec des lentilles d'eau (ou lenticules), autres plantes aquatiques flottantes du genre Lemna (famille des Araceae, auparavant des Lemnaceae). Elle est considérée comme " plante envahissante ".
Fjädermossbräken (Azolla pinnata) är en ormbunksväxt som lever flytandes på vattenytan i sjöar, träsk, långsamt flytande floder eller andra mer eller mindre stillastående vattenmassor. Den är ettårig och varje enskild individ blir upp till 2,5 centimeter bred, men 1–2 millimeter breda blad.[1] Växten kan sprida sig mycket fort och bilda en matta över vattenytan. I USA har den därför klassats som en så kallad noxious weed, alltså en växt som är skadlig för jordbruket eller de lokala ekosystemen, av USA:s jordbruksdepartement.[2] Den kan också orsaka stopp i bevattningspumpar och hindra fiske och båtliv.[3] Den förökar sig både med hjälp av sporer och genom delning, där mittstammen dör och de enskilda grenarna bildar nya individer.
Fjädermossbräken är utbredd i de tropiska och subtropiska av Gamla världen; bland annat i Afrika, södra och östra Asien, Australien och Nya Zeeland.
Fjädermossbräken har tidigare använts som gödning på risfält i Asien, där den lever i symbios med bakterien Anabaena azollae. Bakterierna lever på växten där de binder kväve. I sommarsolen dör sedan växten och sjunker till botten där kvävet frigörs så att det kan tas upp av risplantorna.[1] Den används även som ett läkemedel inom Ayurveda.[4]
Wikimedia Commons har media som rör Fjädermossbräken.
Fjädermossbräken (Azolla pinnata) är en ormbunksväxt som lever flytandes på vattenytan i sjöar, träsk, långsamt flytande floder eller andra mer eller mindre stillastående vattenmassor. Den är ettårig och varje enskild individ blir upp till 2,5 centimeter bred, men 1–2 millimeter breda blad. Växten kan sprida sig mycket fort och bilda en matta över vattenytan. I USA har den därför klassats som en så kallad noxious weed, alltså en växt som är skadlig för jordbruket eller de lokala ekosystemen, av USA:s jordbruksdepartement. Den kan också orsaka stopp i bevattningspumpar och hindra fiske och båtliv. Den förökar sig både med hjälp av sporer och genom delning, där mittstammen dör och de enskilda grenarna bildar nya individer.
Azolla pinnata là một loài dương xỉ trong họ Salviniaceae. Loài này được R. Br. mô tả khoa học đầu tiên năm 1810.[1]
Azolla pinnata là một loài dương xỉ trong họ Salviniaceae. Loài này được R. Br. mô tả khoa học đầu tiên năm 1810.
