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57-493: Watercress or yellowcress ( Nasturtium officinale ) is a species of aquatic flowering plant in the cabbage family, Brassicaceae . Watercress is a rapidly growing perennial plant native to Eurasia. It is one of the oldest known leaf vegetables consumed by humans. Watercress and many of its relatives, such as garden cress , mustard , radish , and wasabi , are noteworthy for their piquant flavors. The stems of watercress are hollow and float in water. The leaf structure

114-730: A comprehensive overview of alien aquatic plants in 46 European countries found 96 alien aquatic species. The aliens were primarily native to North America, Asia, and South America. The most spread alien plant in Europe was Elodea canadensis (Found in 41 European countries) followed by Azolla filiculoides in 25 countries and Vallisneria spiralis in 22 countries. The countries with the most recorded alien aquatic plant species were France and Italy with 30 species followed by Germany with 27 species, and Belgium and Hungary with 26 species. The European and Mediterranean Plant Protection Organization has published recommendations to European nations advocating

171-488: A few. One example of a herbal tonic is raspberry leaf ( Rubus idaeus ) used by pregnant women. This herb has been used since traditional Chinese medicine , and is still popular in China, Europe and North America. Raspberry leaf is used due to a belief that it has no toxic connotations, nor is a medicinal substance, and has nutrients believed to tone the uterus. This is purportedly due to vitamins A , B , C and E found in

228-417: A food source. Examples include wild rice ( Zizania ), water caltrop ( Trapa natans ), Chinese water chestnut ( Eleocharis dulcis ), Indian lotus ( Nelumbo nucifera ), water spinach ( Ipomoea aquatica ), prickly waterlily ( Euryale ferox ), and watercress ( Rorippa nasturtium-aquaticum ). A decline in a macrophyte community may indicate water quality problems and changes in the ecological status of

285-503: A lack of pressure that terrestrial plants experience. Green algae are also known to have extremely thin cell walls due to their aquatic surroundings, and research has shown that green algae is the closest ancestor to living terrestrial and aquatic plants. Terrestrial plants have rigid cell walls meant for withstanding harsh weather, as well as keeping the plant upright as the plant resists gravity. Gravitropism, along with phototropism and hydrotropism, are traits believed to have evolved during

342-618: A practice thought to have originated under the sphere of traditional Chinese Medicine . They were also used in Ayurvedic and Unani practices as well as in Native America. Initially, the use of herbal tonics was embedded within these traditional medicinal practices and cultures. Today, herbal tonics are consumed globally and are used as a general resource in maintaining well-being. They are found in not only hospitals and pharmacies, but in health food stores and supermarkets as well. Although

399-511: A preventative means of medicine, to maintain overall wellness which is similar to how it is used in Ayurvedic and Unani practices. Traditional Chinese medicine link the taste of herbs with their medicinal properties, this process dates back as far as AD 581, during the Late Sui dynasty. Chinese literature denotes four different roles to drugs (which in this case are different herbs used in tonics) –

456-401: Is pinnately compound . Small, white, and green inflorescences are produced in clusters and are frequently visited by insects, especially hoverflies , such as Eristalis flies. Watercress is listed in some sources as belonging to the genus Rorippa , although molecular evidence shows those aquatic species with hollow stems are more closely related to Cardamine than Rorippa . Despite

513-537: Is 95% water and has low contents of carbohydrates , protein , fat , and dietary fiber . A 100-gram serving of raw watercress provides 46 kilojoules (11 kilocalories), is particularly rich in vitamin K (238% of the Daily Value , DV), and contains significant amounts of vitamin A , vitamin C , riboflavin , vitamin B 6 , calcium , and manganese (table). As a cruciferous vegetable , watercress contains isothiocyanates that are partly destroyed by boiling, while

570-410: Is complete, the plant descends through the water column and the roots atrophy. In floating aquatic angiosperms, the leaves have evolved to only have stomata on the top surface to make use of atmospheric carbon dioxide. Gas exchange primarily occurs through the top surface of the leaf due to the position of the stomata, and the stomata are in a permanently open state. Due to their aquatic surroundings,

627-459: Is considered to be the nation's watercress capital. Watercress crops grown in the presence of manure can be an environment for parasites such as the liver fluke , Fasciola hepatica . When introduced into non-native environments watercress can have negative impacts on native species. With the introduction of watercress, the organic matter in the sediment increases which in turn attracts predatory macroinvertebrates that feed on other plants in

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684-653: Is frequently saturated , and are therefore a common component of swamps and marshlands . One of the largest aquatic plants in the world is the Bolivian waterlily , which holds the Guinness World Record of having the largest undivided leaf at 3.2 m (10 ft 6 in) diameter; the smallest is the rootless duckweed , which is only 1 mm (0.039 in) across. Many small animals use aquatic plants such as duckweeds and lily pads for spawning or as protective shelters against predators both from above and below

741-467: Is limited research into the safety and efficacy of herbal tonics – what is known is that some herbs contain specific chemicals and minerals which have known effects on the human body. The use of herbal tonics extends as far back as ancient times – embedded within traditional Chinese Medicine which categorised tonic herbs to ‘Jing’, ‘Qi’ and ‘Shen’ (which can be translated to mind, body and soul.) Traditional Chinese medicine used herbal tonics mainly as

798-482: Is supported by the evidence that several of the earliest known fossil angiosperms were aquatic. Aquatic plants are phylogenetically well dispersed across the angiosperms , with at least 50 independent origins, although they comprise less than 2% of the angiosperm species. Archaefructus represents one of the oldest, most complete angiosperm fossils which is around 125 million years old. These plants require special adaptations for living submerged in water or floating at

855-406: The bioavailability of its carotenoids is slightly increased by cooking. Steaming or microwave cooking retains these phytochemicals a bit better than boiling. Watercress cultivation is practical on both a large scale and a garden scale. Being semi-aquatic, watercress is well-suited to hydroponic cultivation, thriving best in water that is slightly alkaline . It is frequently produced around

912-479: The liver fluke , Fasciola hepatica . In China watercress is often boiled alongside pork and traditional medicinal ingredients to make a wintertime tonic soup, in Vietnam it is generally used raw as a component in salads. Ancient Romans thought eating it would cure mental illness. Twelfth-century mystic Hildegard of Bingen thought eating it steamed and drinking the water would cure jaundice or fever. Watercress

969-463: The Cold War. Adaptogens are believed to regulate the metabolism and increase resistance to stress, one example of an adaptogen is Eleutherococcus senticosus , more commonly referred to as Siberian ginseng . It was one of three plants involved in clinical pharmacological trials, and had statistically significant results in having stimulating and restoring effects. As a result of this, Siberian ginseng

1026-540: The Latin name, watercress is not particularly closely related to the flowers popularly known as nasturtiums ( Tropaeolum majus ). T. majus belongs to the family Tropaeolaceae , a sister taxon to the Brassicaceae within the order Brassicales . In some regions, watercress is regarded as a weed , in other regions as an aquatic vegetable or herb . Watercress has grown in many temperate locations worldwide. Watercress

1083-473: The United States. Adaptogens are present in some herbal tonics, which are purported to improve wellbeing. The first discovered adaptogen was dibazol, in 1947 by Russian pharmacologist Nikolay Vasilievich Lazarev . Dibazol positively affected animals’ resistance against stress Jacob's ladder ( Polemonium ceruleum ) is another herb used in tonics originally called chilodynamia by ancient Greeks. It

1140-634: The cardiovascular system. Throughout modern history tonic herbs were continued to be used globally, entering new cultures and becoming common practice for some. The definition of adaptogens (a naturally occurring substance known to aid stress ) was conceived in Soviet Russia during the Cold War . As a result of clinical studies proving the effectiveness of adaptogens (found in herbal tonics), they were formed into both tablets and concentrated liquids and distributed amongst army and military staff serving during

1197-414: The communist government which came into power in China in 1949. This government pushed for a return to traditional Chinese medicine after modern medicine entered China and dominated hospitals and institutions there. It is now common practice for doctors in China to amalgamate functions of traditional herbal medicine with modern practices. One herbal tonic which dates back to ancient times is Lucerne . It

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1254-507: The distribution of aquatic plants is the availability of water. However, other abiotic factors may also control their distribution including nutrient availability, availability of carbon dioxide and oxygen, water temperature, characteristics of the substrate, water transparency, water movement, and salinity. Some aquatic plants are able to thrive in brackish, saline, and salt water . Also biotic factors like grazing, competition for light, colonization by fungi, and allelopathy are influencing

1311-428: The emperor, minister, assistant and envoy. This translates respectively to the principle drug, the associate drug, the adjuvant drug and the messenger drug. Not all herbal tonics include all four of these components. Having a mix of these balance out toxic qualities of some sole herbs. Today, the use of tonic herbs in China has seen a resurgence. This is in part due to the high cost of modern pharmaceuticals as well as

1368-464: The environment. By inhibiting the cytochrome P450 enzyme CYP2E1 , compounds in watercress may alter drug metabolism in individuals on certain medications such as chlorzoxazone . Due to its fast-growing nature and invasive species status, Nasturtium officinale is prohibited in Illinois . Watercress leaves, stems, and fruit can be eaten raw. Cultivated watercress has the advantage of being free of

1425-677: The headwaters of chalk streams . In many local markets, the demand for hydroponically grown watercress exceeds supply, partly because cress leaves are unsuitable for distribution in dried form and can only be stored fresh for about 2–3 days. Also sold as sprouts , the edible shoots are harvested days after germination. If unharvested, watercress can grow to a height of 50 to 120 centimetres (1 ft 8 in to 3 ft 11 in). Aquatic plant Although seaweeds , which are large multicellular marine algae , have similar ecological functions to aquatic plants such as seagrass , they are not typically referred to as macrophytes as they lack

1482-465: The herb, these vitamins contain tannins and polypeptides , capable of stimulating and soothing. Studies have shown neither benefit nor harm from raspberry leaf during pregnancy. Some herbal tonics have been used for treatment or prevention specific ailments. However, they are not considered a treatment or prevention by the US Food and Drug Administration and thus are not labeled or regulated as such in

1539-479: The important functions performed by macrophyte is uptake of dissolved nutrients including nitrogen and phosphorus. Macrophytes are widely used in constructed wetlands around the world to remove excess N and P from polluted water. Beside direct nutrient uptake, macrophytes indirectly influence nutrient cycling , especially N cycling through influencing the denitrifying bacterial functional groups that are inhabiting on roots and shoots of macrophytes. Macrophytes promote

1596-647: The leaves can photosynthesize more efficiently in air and competition from submerged plants but often, the main aerial feature is the flower and the related reproductive process. The emergent habit permits pollination by wind or by flying insects . There are many species of emergent plants, among them, the reed ( Phragmites ), Cyperus papyrus , Typha species, flowering rush and wild rice species. Some species, such as purple loosestrife , may grow in water as emergent plants but they are capable of flourishing in fens or simply in damp ground. Submerged macrophytes completely grow under water with roots attached to

1653-429: The leaves on the plant that grew while above water, along with oxygen levels being higher in the portion of the plant grown underwater versus the sections that grew in their terrestrial environment. This is considered a form of phenotypic plasticity as the plant, once submerged, experiences changes in morphology better suited to their new aquatic environment. However, while some terrestrial plants may be able to adapt in

1710-430: The leaves' thickness, shape and density and are the main factor responsible for the greatly reduced rate of gaseous transport across the leaf/water boundary and therefore greatly inhibit transport of carbon dioxide. To overcome this limitation, many aquatic plants have evolved to metabolise bicarbonate ions as a source of carbon. Environmental variables affect the instantaneous photosynthetic rates of aquatic plants and

1767-474: The occurrence of macrophytes. Aquatic plants have adapted to live in either freshwater or saltwater. Aquatic vascular plants have originated on multiple occasions in different plant families; they can be ferns or angiosperms (including both monocots and dicots ). The only angiosperms capable of growing completely submerged in seawater are the seagrasses . Examples are found in genera such as Thalassia and Zostera . An aquatic origin of angiosperms

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1824-412: The photosynthetic enzymes pigments. In water, light intensity rapidly decreases with depth. Respiration is also higher in the dark per the unit volume of the medium they live in. Fully submerged aquatic plants have little need for stiff or woody tissue as they are able to maintain their position in the water using buoyancy typically from gas filled lacunaa or turgid Aerenchyma cells. When removed from

1881-563: The plants are not at risk of losing water through the stomata and therefore face no risk of dehydration. For carbon fixation, some aquatic angiosperms are able to uptake CO 2 from bicarbonate in the water, a trait that does not exist in terrestrial plants. Angiosperms that use HCO 3 - can keep CO 2 levels satisfactory, even in basic environments with low carbon levels. Due to their environment, aquatic plants experience buoyancy which counteracts their weight. Because of this, their cell covering are far more flexible and soft, due to

1938-432: The product before it is released to the general public for consumption. Thus, the detriments of consuming herbal tonics are largely unknown to the greater population; further, there is an assumption herbal remedies and medicines are safe. There are accounts of toxicity as a result of consuming herbal tonics causing severe abdominal pain, malaise and in some cases, even liver failure. These adverse effects exist as there

1995-676: The restriction or banning of the trade in invasive alien plants. Herbal tonic In herbal medicine , a herbal tonic (also tonic herbs, tonic herbalism) is used to help restore, tone and invigorate systems in the body or to promote general health and well-being . A herbal tonic is a solution or other preparation made from a specially selected assortment of plants known as herbs . They are steeped in water and drunk either hot or cool. Herbal tonics are believed to have healing properties ranging from relieving muscle and joint pain and extend as far as inhibiting some cancers. Herbal tonics can be dated as far back as 4,000 years ago – as

2052-514: The sedimentation of suspended solids by reducing the current velocities, impede erosion by stabilising soil surfaces. Macrophytes also provide spatial heterogeneity in otherwise unstructured water column. Habitat complexity provided by macrophytes tends to increase diversity and density of both fish and invertebrates. The additional site-specific macrophytes' value provides wildlife habitat and makes treatment systems of wastewater aesthetically satisfactory. Some aquatic plants are used by humans as

2109-426: The short-term to an aquatic habitat, it may not be possible to reproduce underwater, especially if the plant usually relies on terrestrial pollinators . Based on growth form, macrophytes can be characterised as: An emergent plant is one which grows in water but pierces the surface so that it is partially exposed to air. Collectively, such plants are emergent vegetation . This habit may have developed because

2166-492: The specialized root / rhizoid system of plants. Instead, seaweeds have holdfasts that only serve as anchors and have no absorptive functions . Aquatic plants require special adaptations for prolonged inundation in water, and for floating at the water surface. The most common adaptation is the presence of lightweight internal packing cells, aerenchyma , but floating leaves and finely dissected leaves are also common. Aquatic plants only thrive in water or in soil that

2223-607: The stem and root of Ludwigia adscendens , as well as those of the fruit, leaf and stem of Monochoria hastata were found to have lipoxygenase inhibitory activity. Hot water extract prepared from the leaf of Ludwigia adscendens exhibits alpha-glucosidase inhibitory activity more potent than that of acarbose . Macrophytes have an essential role in some forms of wastewater treatment, most commonly in small scale sewage treatment using constructed wetlands or in polishing lagoons for larger schemes. The introduction of non-native aquatic plants has resulted in numerous examples across

2280-616: The substrate (e.g. Myriophyllum spicatum ) or without any root system (e.g. Ceratophyllum demersum ). Helophytes are plants that grow partly submerged in marshes and regrow from buds below the water surface. Fringing stands of tall vegetation by water basins and rivers may include helophytes. Examples include stands of Equisetum fluviatile , Glyceria maxima , Hippuris vulgaris , Sagittaria , Carex , Schoenoplectus , Sparganium , Acorus , yellow flag ( Iris pseudacorus ), Typha and Phragmites australis . Floating-leaved macrophytes have root systems attached to

2337-769: The substrate or bottom of the body of water and with leaves that float on the water surface. Common floating leaved macrophytes are water lilies (family Nymphaeaceae ), pondweeds (family Potamogetonaceae ). Free-floating macrophytes are found suspended on water surface with their root not attached to the substrate, sediment , or bottom of the water body. They are easily blown by air and provide breeding ground for mosquitoes. Examples include Pistia spp. commonly called water lettuce, water cabbage or Nile cabbage. The many possible classifications of aquatic plants are based upon morphology. One example has six groups as follows: Macrophytes perform many ecosystem functions in aquatic ecosystems and provide services to human society. One of

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2394-459: The surface of the water. Some still-water plants can alter their position in the water column at different seasons. One notable example is Water soldier which rests as a rootless rosette on the bottom of the water body but slowly floats to the surface in late Spring so that its inflorescence can emerge into the air. While it is ascending through the water column it produces roots and vegetative daughter plants by means of rhizomes . When flowering

2451-500: The surface. Although most aquatic angiosperms can reproduce by flowering and setting seeds, many have also evolved to have extensive asexual reproduction by means of rhizomes , turions , and fragments in general. Submerged aquatic plants have more restricted access to carbon as carbon dioxide compared to terrestrial plants. They may also experience reduced light levels. In aquatic plants diffuse boundary layers (DBLs) around submerged leaves and photosynthetic stems vary based on

2508-443: The transition from an aquatic to terrestrial habitat. Terrestrial plants no longer had unlimited access to water and had to evolve to search for nutrients in their new surroundings as well as develop cells with new sensory functions, such as statocytes . Terrestrial plants may undergo physiological changes when submerged due to flooding. When submerged, new leaf growth has been found to have thinner leaves and thinner cell walls than

2565-501: The use of herbal tonics has carried through since ancient times, it has been only within the past thirty years that herbal tonics have been used at a large rate globally. Roughly 4 billion people (primarily living in the developing world) annually spend roughly US$ 60 billion on herbal medicines to aid a large range of particular illness, with some individuals turning to herbal tonics due to concerns about that quality, safety, or affordability of orthodox treatments by physicians. There

2622-689: The water body. Such problems may be the result of excessive turbidity , herbicides , or salination . Conversely, overly high nutrient levels may create an overabundance of macrophytes, which may in turn interfere with lake processing . Macrophyte levels are easy to sample, do not require laboratory analysis, and are easily used for calculating simple abundance metrics. Phytochemical and pharmacological researches suggest that freshwater macrophytes, such as Centella asiatica , Nelumbo nucifera , Nasturtium officinale , Ipomoea aquatica and Ludwigia adscendens , are promising sources of anticancer and antioxidative natural products. Hot water extracts of

2679-564: The water flow, capture sediments and trap pollutants . Excess sediment will settle into the stream bed due to the reduced flow rates, and some aquatic plants also have symbiotic microbes capable of nitrogen fixation and breaking down the pollutants trapped and/or absorbed by the roots. Historically, aquatic plants have been less studied than terrestrial plants , and management of aquatic vegetation has become an increasingly interested field as means to reduce agricultural pollution of water bodies . The principal factor controlling

2736-437: The water surface. Aquatic plants are important primary producers and are the basis of food web for many aquatic fauna , especially wetland species. They compete with phytoplanktons for excess nutrients such as nitrogen and phosphorus , thus reducing the prevalence of eutrophication and harmful algal blooms , and have a significant effect on riparian soil chemistry as their leaves , stems and roots slow down

2793-618: The water, such plants are typically limp and lose turgor rapidly. Those living in rivers do, however, need sufficient structural xylem to avoid being damaged by fast flowing water and they also need strong mechanisms of attachment to avoid being uprooted by river flow. Many fully submerged plants have finely dissected leaves, probably to reduce drag in rivers and to provide a much increased surface area for interchange of minerals and gasses. Some species of plants such as Ranunculus aquatilis have two different leaf forms with finely dissected leaves that are fully submerged and entire leaves on

2850-419: The whole body of many ponds to the almost total exclusion of other plants and wildlife Other notable invasive plant species include floating pennywort , Curly leaved pondweed , the fern ally Water fern and Parrot's feather . Many of these invasive plants have been sold as oxygenating plants for aquaria or decorative plants for garden ponds and have then been disposed of into the environment. In 2012,

2907-416: The world of such plants becoming invasive and frequently dominating the environments into which they have been introduced. Such species include Water hyacinth which is invasive in many tropical and sub-tropical locations including much of the southern US, many Asian countries and Australia. New Zealand stonecrop is a highly invasive plant in temperate climates spreading from a marginal plant to encompassing

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2964-452: Was eaten by Native Americans . Some Native Americans used it to treat kidney illnesses and constipation , and it was thought by some to be an aphrodisiac . Early African Americans used the plant as an abortifacient ; it was believed to cause sterility as well. The new tips of watercress leaves can be eaten raw or cooked, although caution should be used when collecting these in the wild because of parasites such as giardia . Watercress

3021-596: Was first commercially cultivated in 1808 by the horticulturist William Bradbery along the River Ebbsfleet in Kent . Historically important areas of cultivation also included Hampshire , Stamford , Lincolnshire , and St Albans , Hertfordshire . Watercress is now grown in several counties of the United Kingdom , most notably Hampshire, Dorset , Wiltshire , and Hertfordshire . The town of Alresford , near Winchester ,

3078-510: Was found in Persia by Emperor Darius in roughly 500 BC and was renowned for its fattening and energising abilities. Not only was it consumed by humans, but was also fed to cattle, and often horses during long journeys. Interestingly, it is believed liqueurs were created to ward off ageing for Louis XIV in 17th century France. Sugar mixed with herbs known for mending particular ailments form heart tonics believed to maintain optimal functioning of

3135-519: Was introduced into China through Hong Kong and Macao in the 1800s from Europe. Its cultivation also spread to highland areas in the tropical regions of Asia. Clear fast-flowing chalk streams are the primary natural habitat for wild watercress in the British Isles . Many settlements in England were named from Old English êacerse (êa..cerse) " water−cress ". In the United Kingdom , watercress

3192-589: Was used in both capsule and extract form. Herbal tonics are used in many different cases for many different reasons including the treatment of psychological, physical, and spiritual conditions. People who consume herbal tonics often do so in pursuit of preventing illness and maintaining optimal health. Herbal tonics are also sometimes used similarly to coffee for a purported stimulating or calming effect in time of stress. Additionally, herbal tonics are used for physiological relief – to aid muscle pain, soothe tension headaches and alleviate unsettled stomachs, to name

3249-521: Was used to cure the vapours ( hysteria and other cases of a patient losing mental focus), and still is used today to assist individuals experiencing hysteria though most physicians do not accept hysteria as a valid medical diagnosis . Reports of adverse effects regarding herbal tonics are at a minimum, largely because they are not treated as regulated pharmaceuticals . Instead, herbal tonics are predominantly marketed as dietary products; this means there are less regulations (and consequent studies) on

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