Thursday, 25 October 2018

Importance and Uses of Bryophytes

Uses of Bryophytes 

Bryophytes form an important part of vegetation in cold temperate regions of the world including Himalayas. Studies on the uses of bryophytes in the daily rives of the native people have revealed that in these regions bryophytes are widely used as medicine, construction materials insect repellents, pads and stuffing, packing, chinking materials and smoke filters.

1. As Medicine 

In ancient times bryophytes have been used as herbal medicines in various parts of the world. Dioscorides ascribed medicinal properties to Marchania polymorpha. During the middle ages, the large thallose liverworts Were interpreted according to the Doctrine of Signatures. The decoction of liverworts was supposed to be effective in the treatment of disorders of liver, and that of the “hairy-cap moss” to beautify ladies hairs.

In Northern Montana (USA) Potytrichum juniperinum is still used for preparing various medicines. In Kumaon region (North-Western Himalayas) liverworts Marchania polyrnorpha and M. palmata are used as medicine for boils and abscesses, whereas mosses are used in (he preparation of an ointment for cuts, bums and wounds. In China, more than 30 species of bryophytes have been recognized as curative agents. Clinical researches are also being carried out to confirm the effectiveness ofthese medicines and it has been observed that the extmct of moss Rhodobryum giganteum, which is used to cure angina (an attack of intense constricting pain), increased the rate of flow in aorta of white mice by over 30% causing a reduction in the amount of oxygen resistance.

Modem phytochemists and biochemists have isolated a vast number of biologically active organic compounds from bryophytes which are of potential use in pharmaceutical industry. It has been demonstrated that certain products of bryophytes inhibit the growth of micro- organisms. Three prenylbibenzyls from Radula spp. inhibit the growth of Staphylococcus aurens.

Many species of bryophytes have been shown to possess antitumor activity. The first antitumor active compound, diplophylline, was obtained from liverworts. This compound shows significant activity against human carcinoma. Antitumor sesqueterpenoids have also been isolated from many liverworts:

The following antitumor.sesqueterpenoids have been isolated from various bryophytes.

Sphagnum has been used as absorbent dressing for centuries. Sphagnum dressings were first used on a large scale during the Russo-Japanese war, 1904- 1905. The following were the advantages of Sphagnum dressings over cotton.
  1. They absorbed 16-20 times their own dry weight of liquid, whereas cotton dressings could only absorb 4-6 times. 
  2. They were coo! and soothing because the moss is porous a dressing was found to be comparatively dry for 24 hours after an operation in cases where the wound had bled quite freely. 
  3. The dressing could be left on for up to 2-3 days which is much longer than cotton dressings. 
  4. Sphagnum itself has mild antiseptic properties not possessed by cotton. 
Effective Against Plant Pathogens: Bryophytes also show activity against some plant pathogens. Extract of the liverwort - Herbertus aduncus inhibits the growth of some plant pathogenic fungi. .Many species of’ mosses (e.g. Dicranum scoperium and D. japonicum) contain some rare fatty acids which completely inhibit the growth of the Fungus causing rice blast, pyricularia oryzae. 

Table 15.1 : Medicinal Usas of Bryophytes. Medicinal value giganleum for the treatment of cardio-vascular diseases and nervousness commune to reduce inflammation, as an antifever agent, diuretic (causing increased output ofurine), laxative and hemostatic agent microphyllum for tonsillitis, bronchitis, tympanitis, asid cysticis (an inflammation ofthe uninary bladder) conicum and . (mixed with vegeiative oils) as o├Čntrnents for boils, eczema, curs, bites, wounds and burns as an antibacterial agent for swollen throat

2. As Construction Material. 

In areas where woody plants are scarce, the tiny bryophytes have commonly been utilized in number of ways. They are also used in the construction of houses and for their furnishings,

The aquatic moss Fontinalis antipyretica is used by Nordic people for filling spaces between the chimney and walls to prevent fires. Several mosses are used as chinking (chink-a crack or narrow fissure) materials. Similarly, in Alaska,, thinking of wooden and log cabins is done using bryophytes. The shepherds in the Himalayan highlands also use bryophytes for chinking. In northern Europe Sphagnum is stuffed between timbers used in houses to deaden the sound. Mosses have also been used in making huts by herdsman in Alps. Neckera complanata and other mosses are used for plugging the seams and cracks of boats.

In the Scottish highlands Sphagnum mixed in tar is used for plugging the seams. In Russia, pressed and heated raw peat is used for making slabs which are used for insulation of domestic housing and refrigeration.

Recently, new construction materials like “peat Crete”, “peat wood”, and “peat foam” have been developed from Sphagnum using certain binders for solidification and strengthening.

3. Use as Decorative Material 

In decorative industry and floral trade mosses play significant role. In countries like Japan. England, France, Finland and America mosses are used for decoration of ladies hats. In the floral trade mosses are marketed as “sheet moss” or “blanket moss” and are used commonly in this industry the year-round. The moss sheets form blanket material for Christmas tree yards and nativity scenes. The decorative uses of mosses are as follow:
  1. Dicranum scopariurm - for forming banks of green in shop window displays 
  2. Rhytidiadeiphus loreus, R. triquetrus and Hyloconium splendens - as green carpets for floral exhibitions 
  3. Climacium americanum - fashioned into wreaths and crosses 
  4. hylocomium splendens a for making moss roses y)
  5.  Climacium dendroides - (dyed) for decorating women’s hats 
Some aquatic bryophytes are used in aquaria. These bryophytes are also useful to fishes because they provide oxygen and egg-laying substrata.

4. As Packing Material 

Mosses are suitable for packing purposes because they have soft elastic texture and are not easily attacked by micro-organisms. in the western United Slates mosses are used for packing vegetables. In tropics, leafy liverworts are used for packing, largely because of their abundance. In the Himalayas, apples and plums in particular are wrapped in mosses. Nurserymen in India use wet Sphagnum for sending or supplying live plants and also for shipment of vegetables, cacti, ferns and other delicate plants. Moist Sphagnum ¡s used for packing live frogs, snakes, lizards) worms arid some insects for shipment.

5. House Hold Uses 

As Absorbent 

A layer of Sphagnum is used in hiking boots for cushioning the foot and absorbing moisture e and odour. Dry Sphagnum is used as diapers and in cradles to keep babies clean and warm.

In Mores, mosses are used th making moss beds and pillows. Laplanders use Polytrichum commune for this purpose. ¡n alpine regions of the North Western Himalayas Indians make beddings, mattresses, cushions and pillows by stuffing mosses into coarse linen sacks or by spreading them on muddy floor of huts. Mosses are preferred due to their soft texture, insect-repellent property and resistance to rotting.

Insect Repellents 

It is generally known that bryophytes even as herbarium specimens, are hardly ever attacked by microorganisms arid insects. Many bryophyte species have their own peculiar odour and . taste. In many villages of Naini Tal arid Pithoragarh, mosses in particular are used as insect repellents. The locally available mosses and liverworts are dried and coarsely powdered. The moss powder is sprinkled over the grains and pulses that are to be stored in containers.

Smoke Filters and Pads 

Bryophytes are used as smoke filters in the bubble-bubble or “hookah” in the Kumaon Himalayas.

Women who have to fetch water from long distances in the villages of Kumaon, make a round base of moss mats called “sirona” which is kept on the head to hold the pitcher.

6. Treatment of Waste Water 

Sphagnum has been used as an effective filtering and absorptive agent for the treatment of waste water and effluent of factories with acidic and toxic discharge containing heavy metals, arid many organic substances. Peat can also be used as an absorbent for oil spills and as filtering agent for oily waste water in vegetable oil factories.

7. Mosses as Animal Food and Shelter 

Food 

The biomass of mosses in many vegetation zones of the world is considerable. However, it is in tundra that they are most abundant. The caloric content of mosses from the Canadian tundra is about 4..5-5.O kcal/g. This is comparable to higher plants growing in the same habitat.

Other than proteins and fats mosses contain a large amount of lignin-like compounds. It is reported that they are rich in vitamins, especially B2.

Mosses are consumed by many animals like bison, reindeer, rodent’s insects and birds. Another interesting use is feeding of mosses to baby pigs. If pigs are born anemic, the millec sphagnum feed is ideal for binding the iron and vitamins fed to baby pigs. It has ability to absorb and hold nutrients.

Shelter 

Some insects and birds use mosses for building shelter. A wide range of birds use green leafy garnetophores of mosses to construct nests which provide protection to their eggs and young ones. Some birds like Pink Robin of Australia make very complex nests. They use mosses for making the main body of nest and line it with tree fern.

8. Uses of Bryophytes in Horticulture 

Bryophytes are useful in horticulture because of their high water holding capacity. You may have observed money plant or other climbers growing in pots around sticks. They are used for providing moisture to the plant.

Gardeners use moss wrapped hanging baskets arid pots for cultivating Begonias. Fuchsia and Orchids. its is observed that when plants are grown in a pot with a layer of moss sandwiched between the humus-rich top and bottom soil, they grow well and produce buds and flowers more profusely in comparison to the ones grown without it.

Mosses are used as soil additives. Moss carpet serves to stabilize the soil and retain its moisture. When Sphagnum is mixed with soil or spread over the ground it lightens soil mixture, discourages weed growth and prevents excessive drying of the upper soil layers. Mosses are used as ground cover for making Bonsai.

In Japan mosses have long been used as precious attributes of gardens. They are useful as an evergreen ground cover in much the same way as lawn grasses. In some countries mosses are used as seed beds. It has been reported that pioneer white spruce in Nova Scotia (Canada) germinates most prolifically in carpets of Polytrichum. Similarly, the mosses, especially Hypnum imponens provide the seedling bed for Tsuqga and Betula. Extract of Sphagnzam promote germination of Jack Pine seeds. Mosses such as. Pleurozium schreberi has been found to act as good seed beds for the germination of seeds of pines.

Ecological Role of Bryophytes 

1. Bryophytes as Pioneer of Vegetation 

Many bryophytes arc the first ones to appear on open and often nutrient-poor sites where no other plant is able to grow. For instance they grow on bare rocks and on recently deposited volcanic ash. Gradually, the bryophytes build up an organic layer that is invaded by microorganisms. resulting in changes in the mineral substratum beneath. This increases nutrient availability makes the site suitable for invasion by vascular plants. In (his way, bryophytes help in succession of plants on bare rocks by becoming pioneer plant community (pioneers-first to appear). Several bryophytes like Andreaea are restricted mainly lo bare rock surfaces. Most of these bryophytes are highly tolerant lo extended period of desiccation.

The mosses are also pioneer species on burnt sites. Every year large areas of grassland, and temperate and tropical forests catch fire. The resulting tracts of land provide habitats for the succession of mosses Like Funaria and Polytrichum.

Mosses are pioneers in dune systems as well. They help in retaining moisture and stabilizing dunes that otherwise are at the mercy of the wind, e.g. Cerarodon and Tortula.

2. Role of Bryophytes in Soil Erosion 

‘You have learnt that bryophytes grow as compact cushions forming a carpet on the forest floor. Actually. their rhizoids bind soil particles together and also interweave with the rhizoids of adjacent plants keeping the whole cushion compact and difficult to detach from the soil. The soil particles thus trapped do not flow along with water during floods.

The colonization of bryophytes on the roadside is important in stabilizing these sites. Species of barbula, weissia, and Bryum are pioneers on new road banks.

Extensive sand dune systems occur along many sea coasts of the world. Mosses play a very important role in helping to retain moisture and stabilize dunes. Such mosses can survive even if they get covered by sand. An example of such a moss is Ceralodon purpureus.

Mosses have a potential role as inhibitors of soil erosion due to (heir trample-resistant structure and their high regenerative ability.

In present times, certain mosses like Polytrichum. Alrichum and Ceratodon are grown to prevent soil erosion around fruit trees such as apples and pears.

Bryophytes as Indicators 

Certain mosses have preference for a special kind of substrate for their growth. Therefore, some of them may serve as the indicators of mineral deposits, pH condition of the substratum and also of a particular seed plant community, and pollution and its levels. These are discussed in detail below.

1. Indicators of Mineral Deposits 

Some mosses are restricted to the soil rich in a particular metal(s). The metal(s) often gets accumulated in the plant. By studying the distribution of such plants or analyzing their metal contents, it is possible to discover new mineral deposits. ‘This technique is known as geobotanical prospecting. In Almora, Naini Tal and Pithoragarh districts in the Kumaon region of North Western Himalayas various mineral-rich substrates have been recognized. Each mineralized area has a characteristic bryoflora of its own. The distinction is so pronounced that the bryoflora provides an idea of the precise nature of the underlying substrate. Some of the examples are as follows:
  1. Granite and Mica - Bryophytes belonging to order Grimmiales are the invaders and sole colonizers of smooth, polished surfaces of mica rocks, granites and other rocks. Hard granite surfaces are always colonized by Grimmia spp. and Rhacomitrium himalayanum. The colonization is so sharply delimited that one can predict the substrate by merely studying the moss. 
  2. Dolomite rocks - These rocks are a characteristic feature of the Himalayan geology. The substrates are calcium-rich. The mosses growing on these substrates have a remarkable capacity to absorb and accumulate different amounts of calcium from the substrate. The mosses which are always present on such sites are - hyophila involutca, - and Tortella tortuosa
  3. The magnesite (Mgco3) - One of the largest deposits of this minerals in India is at Kumaon. At all sites the large magnesite deposits present a strikingly barren appearance. The only species of moss growing on these sites is Hymenostylium recurivirostrum. 
  4. Copper - Some species of mosses serve as indicators of high copper concentrations in the substrate and arc known as “copper mosses”. it is suggested that the copper concentration tolerated by the “copper mosses” is lethal to other plants and thus bryophytes have no competition on such sites. The important copper mosses are - Mielichhoferia elongata and Scopelophila cataracictae which can serve as indicator of copper. 

2. Indicators of pH 

Some bryophytes grow only on the soil that is at particular pH. So, the presence of a particular species indicates the acidic or alkaline condition of the soil.
  1. The mosses also grow on hematite (ore of iron) with alkaline pH (7.3-7.6). It is a well known fact that in an alkaline medium. iron remains unavailable to most of the plant. 
  2. Some bryophytes grow only on strongly acidic, highly soluble, iron enriched impolitic substrates. Iron is readily available on such substrates. These substrates have pH 2.9- 4.1. , Polyirichum is a reliable indicator of acidic conditions.
  3. Gypsum containing areas are alkaline to varying degrees and even contain acidic pockets. The moss Campylopus grad/is serves as an example of a species that is tolerant to both acidic and basic conditions over a pH range of 4.9-7.8. 

3. As Indicators of Seed Plant Community 

Some bryophyte species are consistent inhabitant at the sites where a particular seed plant community is growing, so these species can be used as indicator species. While some other persist at localized sites though the original vascular plant vegetation gets destroyed due to some reason. Consequently, they become useful remnants lo indicate the past existence of a forest or non-forest vegetation and can be used as indicators as to which vegetation could be effectively regenerated on that site. ,

4. Indicators of Air Pollution 

In post 12 you have learnt that lichens are bioindicators of pollution. Similarly bryophytes can also be used as bio indicators of pollution as they are sensitive to SO2, fluorides and heavy metals. They show symptoms of injury when exposed to minute quantities of 6g -Bryophytes pollutants. Exposure to SO2 results in loss of green colour. The leafy liverwort Radula Complanata changes in colour within ten minutes and its chloroplasts are destroyed at concentration of 120 ppm. Bryophytes are also very sensitive to hydrogen fluoride and show symptoms of injury at concentrations as low as 0.001 to O. 1 ppm. The colour of leaves of moss Pylaisiella poiyantha changes to brown at low concentration and appears burnt at higher concentration.

Some bryophytes have the capacity to absorb and retain pollutant in quantities much higher than those absorbed by other plants growing in the same habitats. These can be used to lower the concentration of certain pollutants in the environment Analysis of such bryophytes can also provide the idea of the degree pollutant present in that area. Heavy metals constitute a very important class of pollutants. The most significant among these are lead, cadmium, arsenic and chromium. Lead is most toxic metal. You may know that it is used as anti-knock compound and is released in the automobile exhaust. It is found that lead content of mosses growing at a distance of 2 meter away from anti-knock manufacturing factory was found to be 320 ppm. Similarly, Zinc was accumulated 1 3 1 5 ppm in moss (Hypnum cupressforme) growing at a distance of three miles away from the manufacturing factory.

Herbarium specimen’s of three mosses which were collected at intervals during 1860 to 1968 were tested for lead contents. The results are given below:

Table :.Lead Content in Herbarium Specimens of Bryophytes.

Time lead content ppm
1260-187520 
1875-190040
1900-1950 45
1950-1960  80-90

These results concide with the amount of lead released in the atmosphere during those periods.

Indicators of Water Pollution 

Bryophytes can also act as indicator of water pollution. For example, Amiblystgium riparium was found to be absent in the upper part of the river with clean water. However, it appeared at a place where the quality of river water deteriorated due to joining of a polluted tributary coming from a village. This species seems to be an indicator of more or less polluted water. Aquatic bryophytes can be used for monitoring heavy metal pollution as they accumulate them in high concentration. Jun Germania spp. and Scapania spp. accumulate mercury and thus can be used for monitoring its concentrations.

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