Documentation of Wetland Plant Diversity with Indigenous Uses in Nepal - a Case Study of Some Wetlands of Two Valleys (Kathmandu and Pokhara)

The paper enumerates the traditional uses of 55 plant species belonging to 47 genera representing 36 families, which are used by the local communities of some wetlands of two valleys (Kathmandu and Pokhara) of Nepal for the treatment diseases and other uses. Some of useful species are under serious threat due to unsustainable activities and land-use changes. In the paper, some recommendations have been made to integrate conservation measures for the habitat preservation and documentation and sustainable managenet of the useful wetland plants with indigenous etheno-knowledge and practices before some of these are eliminated.
 
Documentation of Wetland Plant Diversity with Indigenous Uses in Nepal
- A Case Study of Some Wetlands of Two Valleys (Kathmandu  and  Pokhara)
                                      Ananda R. Joshi  and  Kunjani Joshi*  
                              SchEMS, Pokhara University, Kathmandu, Nepal
             *Department of Botany, Patan Campus, Tribhuvan University, Nepal
                   Email: joshi_ananda @yahoo.com, [email protected]

                                                      Abstract
        The paper enumerates the traditional uses of 55 plant species belonging to 47 genera   
        representing 36 families, which are used by the local communities of some wetlands of
        two valleys (Kathmandu and Pokhara) of Nepal for the treatment  diseases and other uses.  
        Some of useful species are under serious threat due to unsustainable activities and land-use  
        changes. In the paper, some recommendations have  been made to integrate conservation  
        measures for the habitat preservation and documentation and sustainable managenet of the  
        useful wetland plants with indigenous etheno-knowledge and practices before some of these  
        are eliminated.
 Key words: Wetlands, plant biodiversity, ethnobotany, conservation, sustainable management, Nepal
                         
Introduction
Nepal's position at the junction of the Indo-Malayan and Palaearctic biogeographic realms along with its diverse physiography and varying climatic zones has contributed to the occurrence of over 240 ecologically important wetland ecosystems with diverse flora and fauna (Department of National Parks and Wildlife Conservation, 1995). Some of the major dominant wetland angiospermic plants are Hydrilla verticillata, Utricularia aurea, Vallisneria nataus, Ceratophyllum demursum, Azolla imbricate, Eichhornia crassipes, ipomea aquatica, Lemna minor, Trapa spp., Pistia stratiotes, Sagitaria guyanensis, Nelumbo nucifera, Nymphoides indica etc. Besides these, algae, aquatic fungi, bryophytes  and pteridophytes are also major parts of the wetland ecosystem. This remarkable diversity has made Nepal a variable gene bank for a number of valuable species.       
The local communities are dependent on the wetland plant resources for their various basic needs. At present, wild and useful plants as well as their habitats are under serious threat due to habitat destruction, loss of ecosystem integrity, over-exploitation of resources, introduction of  alien invasive species, unplanned land use and application of inappropriate technologies. The ethnobotanical knowledge and practices are also in danger of  being lost in country. The loss of traditional knowledge in a culture that is undergoing a rapid change is as irreversible as the loss of plant species (Joshi and Joshi, 2005). Therefore effort should be made to document the useful plants and their ethnobotanical uses before much of this is eliminated. Documentation of the useful species and indigenous knowkedge and practices relating to the utilization of the species are very mearged (Shrestha, 1994; Joshi et al, 2001; Joshi, Shrestha and Joshi, 2003; IUCN, Nepal, 2004; Joshi and Joshi, 2005). During the ethnobotanical survey,  an attempt has been made  to collect ethnobotanical information with the documentation of the useful species  from the wetlands of Kathmandu and Pokhara valleys.
Indigenous uses of plants of some wetlands of two valleys  -  a case study
The wetlands of  two valleys : Kathmandu Valley of the Central Development Region and Pokhara valley of the Eastern Development Region have been selected for the case study.
Kathmandu Valley, a tectonic basin, is almost circular and bowl-shaped with the highest peak of Phulchoki on the southeast. The ecosystems of the area are diverse with alluvial plains, fans, river terraces, moderate to steeply sloping terrain and water bodies with complex geomorphology and diverse climatic conditions. The main vegetation types prevalent in the valley are Schima-Castanopsis on the valley floor and hill slopes, Pinus roxburghii on lower hill slopes and on the southern aspects, and oak (Quercus spp.) and rhododerndron (Rhododendron spp.) on the upper reaches of valley hills. Various forms of aquatic life are dominantly found in the rivers, ponds, lakes etc. The  area is inhabited by different ethnic groups (brahmin, chhetri, newar, tamang, gurung, damai, kami etc.), with rich in traditional knowledge and practices.
Pokhara Valley, a popular tourist distination, has moderately steep to very steep mountain terrain with many attractive lakes (Phewa, Begnas and Rupa lakes). The area surrounding the Pokhara valley consists of tropical to subtropical forests. The valley at its lower limit (especially 900 - 1700m) embraces natural belt of Shorea robusta mixed with Pinus spp., Schima wallichii, Castaropsis indica and patches of Alnus nepalensis. Among the aquatic species, species of Lemna, Echhorina, Hydrillla, Utriculatia, Ceratophyllum, Nymphaea, Nelumbo, Sagittaria are mainly distributed in the water bodies. The valley is inhabited by different ethnic tribes, which are rich in folk - lore.

For the study of  wetland plant wealth in and around the wetlands (ponds, lakes, rivers) survey tours were conducted during different seasons (2004- 2007) and ethnobotanical information and useful species were gathered during the field trips. Interviews and discussions were performed with local informants, that include traditional healers / -jkankri", teachers, fisherman,   and experienced village elders (Joshi and Edington, 1990). During the field survey, a series of questions concerning the various uses of plants, parts of  medicinal plants used for treatment, indigenous knowledge and people's believes were explored and recorded. Plant materials were taxonomically identified with the help of related botanical references. Voucher herbariums and specimens have been deposited in SchEMS, Pokhara University, Kathmandu, Nepal.

Results and Discussion
The local communities of the both study areas  have a long tradition of using the  plant resources of wetlands for their various basic needs such as food, medicine, fodder, green manure, rawmaterials and other  miscellaneous uses. The results of the field study are presented in Table 1, where species are listed alphabetically by genus-species and family and their local name, growth-form and uses.
TABLE 1. Ethnobotanical uses of aquatic species and wetland dependent plants of two valleys (Kathmandu  and Pokhara)
        (E= Emergent; FF= Free floating; FLR= Floating leaved rooted aquatics; S = submerged)
Scientific Name/Family Local name Growth Form Uses
Ageratum conyzoides L. (Asteraceae) Ganmane Ghans E -- Root and leaf are pounded and  paste is applied on cuts and wounds for rapid healing. -- Plant is used as fodder.
Ageratum  houstonianum Mill. (Asteraceae) Nilo
Gandhe
E -- Plant decoction is drunk about three  teaspoonsful three times a  day to treat irregular mensuration. -- Fresh leaves are chewed  to treat gastritis. -- Juice of fresh leaves  is rubbed  on the forehead to  releave headach.
Alternanthera sessilis (L.)  DC. (Amaranthaceae) Saranchi sag; Bhirangijhar E -- Tender parts are used as vegetable. -- Root is pounded and infused in hot water and infusion is drunk  to treat dysentery. -- Juice of the plant is also applied to cure  scabies.
Amaranthus spinosus L. (Amaranthaceae) Kande lundo, Latte
E -- Tender parts are eaten as vegetable. -- Cushed leaves are rubbed on affected parts to treat  skin disease. -- Plant is used as fodder
Amaranthus viridis L. (Amaranthaceae) Lunde sag, Latte sag E -- Tender shoot is used as vegetable
Argemone maxicana L. (Papaveraceae) Thakal E -- Root is used in skin diseases. -- Pounded seeds mixed in oil is Applied in eczema and in itcing
Artemisia indica Willd. (Asteraceae) Titepati E -- Juice of leaves is taken to treat  cough and  fever. -- Leaf paste is applied in the affected  parts to treat skin diseases. -- Leaves have insecticidal properties  and place in the mouth of  grain bags to protect entrance of pests.
Azolla imbricate (Roxb. ex Griff.) ) Nakai (Azollaceae) Pani uneu FF -- Whole plant are used as green manure.
-- Food for fishes and ducks
Cannabis sativa L. (Cannabaceae) Gaanja,
Bhang
E -- Seeds are chewed and shallowed to relieve  pain and disorder of the stomach. — Crushed fresh leaves are rubbed on the affected area for treatment of skin infection,
Centella asiatica  (L.) Urb. (Apiaceae) Ghodtapre E -- Infusion of plant is used in leprosy.  -- Leaf juice s given  to cure sensation of internal heat  and treat fever. -- Vegetative tender  parts are used as   food
Capsella bursa-pastoris  (L) Medikus (Brassicaceae) Tori ghans E -- Tender parts are eaten as vegetable. -- Dcoction  of plant is drunk to lower blood pressure
Ceratophyllum demursum L. (Ceratophyllaceae) Patai S -- Plants are a source of food for  fishes and ducks. -- Plant is also used as green manure
Ceratopteris thalictroides  (L) Brongn (Parkeriaceae) Dhaniyajhar; Pani dhaniya E -- Tender parts are used as vegetable
Chenopodium album L. (Chenopodiaceae) Bethe;
Batuwa
E -- Tender shoot is used  as vegetable. -- Plant juice istaken orally for treatment of pain of joints and as health tonic .
Colocasia esculenta (L) Schott (Araceae) Karkalo E -- Corm is taken as vegetable
Cyperus  esculentus L. (Cyperaceae) Mothe E -- Herb is used as fodder
Cyperus rotundus L. (Cyperaceae) Mothe E -- Root juice is drunk as an alithelmintic medicine to treat \intestinal worms. -- Plant paste is applied to cure rheumatic problems. -- Plant is used as fodder
Eclipta prostrata (L.) Roxb. (Asteraceae) Bangearaj, Bhangeree, Samo ghans
E -- Root juice is taken  to cure fever.   -- Plant  paste or juice is applied in cuts  and wounds. -- Seed paste is applied on the affected areas to relieve rheumatic pain. -- Plant is used as fodder
Eleocharis dulcis  (Burm.f.) Trin. ex Henschet (Cyperaceae) Suire E -- Vegetative  parts are eaten. -- Plant is used as fodder
Eichhornia crassipes  (Mart.) Solms. (Pontederiaceae) Jalkumbhee FF Plant is used as food for pigs and sheep and  also used as green manure
Equisetum debeli Roxb. ex Vaucher (Equisetaceae) Kurkure E -- Plants are used as green manure. -- Juice of leaf is drunk  for curing fever. -- Plants are pounded and paste  then applied for curing bone fracture
Eupatorium  adenophorum Spreng. (Asteraceae) Banmara E Freshly crushed tender shoots and leaves are applied externally on cuts and wounds for rapid healing
Floscopa scandens Lour. (Commelinaceae) Kane E Plant used as fodder
Hydrilla verticillata (L.f) Royle (Hydrocharitaceae) Pani jhyau, Sewar,
Khasi
S -- Whole plants are used as green manure. -- Plant  used as fodder. -- Food for fish and ducks
Hygrorhyza aristata  (Retz.) Nees ex Wight & Arn. (Poaceae) Navo dhan FF -- Tender parts are eaten. -- Plant is used as fodder
Ipomea aquatica Forssk. (Convolvulaceae) Kalami sag FF -- Young shoots are used as vegetable. -- Plant is pounded and infusion is drunk to cure jaundice. -- Plant paste is applied to cure piles. -- Plants is used as food for fish and duck
Justicia diffusa Willd. (Acanthaceae) Ghyuru puju E -- Whole plant are pounded and juice is drunk twice  a day for five conscutive days to  treat bronchitis.
-- Leaves are used as insect repellent and disinfectant
Leersia hexandra Swartz. (Poaceae) Karaute
Jhar.
Navo dhan
E Plant used as fodder
Lemna minor L. (Lemnaceae) Leu FF Plants are used as green manure  and  as food for fish and duck
Marsilea quadrifolia L. (Marsileaceae) Charpate
Behuli
E Tender vegetative parts are eaten as vegetables
Mentha spicata L. (Lamiaceae) Pudina E Tender parts are used in  preparing pickle
Monochoria vaginalis (Burm.f.) C. Presl. (Pontederiaceae) Karkale jhar E Tender parts are eaten as vegetable
Nelumbo nucifera Gaertn. (Nelumbonaceae) Rato kamal FLR -- Flower is taken to relieve diharrhea and dysentrea, -- Flower and seeds are boiled and  taken to control high fever. -- Seeds are used as  tonic. -- Plant is also used as fodder
Nymphoides indica (L)  Kuntze (Menyanthaceae) Pyakute FLR -- Decoction of the plant is drunk three teaspoonful every morning to  treat  jaundice. -- Root power is used in dysentery
Oxalis corniculata  L. (Oxalidaceae) Chariamilo E -- Plant juice is used to cure gastrointestinal disorder and dysentery.
-- Leaves are eaten.
Persicaria barbata (L.) H. Hara (Polygonaceae) Pirre jhar E -- Young leaves are used to poison fish.
-- Root powder is applied on scabies
Persicaria hydropiper ( L.) Spach. (Polygonaceae) Pire jhar E -- Crushed plants are used to kill fish.  -- Plant is also employed as fleas repellent.  -- Juice of root is drunk for treatment of removing stone from urinary bladder.
Persicaria lapathifolia (L.) Gray (Polygonaceae) Pirre E -- Crushed plants are used to kill fish
Plantago major L. (Plantaginaceae) Isabgol E -- Ponded leaves are applied to cuts and wounds. -- Decoction of seeds, roots, and leaves are taken  to treat stomach disorder. -- Root paste is applied to cure piles
Ranunculus scleratus L. (Ranunculaceae) Jal dhaniya, Nakakore E Plant is powdered, then applied to the affected parts to treat skin diseases
Rorippa  nasturtium - aquaticum (L.) Hayek (Brassicaceae)
Sim rayo

E

Tender parts are eaten as vegetable  after proper boiling
Rubia wallichina Decne. (Rubiaceae) Mangitho E Whole plant is used as  tonic
Rumex nepalensis Spreng.. (Polygonaceae) Halhale E -- Tender shoots are cooked  as vegetable.
-- Crushed leaf extract is applied externally  on   cuts, wounds, boils and blisters
Sagittaria  guyanensis Kunth. (Alismataceae) Karkale jhar FLR Plant juice is drunk to cure  fever
Schoenoplectus  juncoides (Roxb.)Palla (Cyperaceae) Gud mothe E Plant  used as fodder
Schoenoplectus  mucronatus  (L) Palla (Cyperaceae) Gud mothe E Plant  used as fodder and for mat Making
Solanum nigram L. (Solanaceae) Jungali
Bihi,
Kaalo bihin
E Fruit is used to cure headache and body pain
Spirodela polyrrhiza  (L) Schleider (Lemnaceae) Leu FF Food for fish and ducks
Trapa bispinosa Roxb. (Trapaceae) Simalkande, Bhaise kanda; Singada FF -- Nuts are edible. -- Nuts are used to treat diarrheria
Trapa  quadrispinosa Roxb. (Trapaceae) Simalkande, Gai kanda, Singada FF -- Nuts are used as food. -- Powder of nuts is given in nervous diseases
Trifolium repens L. (Fabaceae) Beuli, Pyauli,
Beulee
E Plant is used as fodder
Urena lobata L. (Malvaceae)
Nalukuro, Thulobolu E Root paste is applied externally on the affected areas to treat rheumatic pain
Urticularia aurea Lour.
(Lentibulariaceae)
Simghans S Plant power is used to cure cuts and wounds and as green manure 
Utricularia bifida L. (Lentibulariaceae) Simghans S Plants is used as green manure and also used in treatment of urinary  diseases
Vallisneria nataus  (Lour.) H. Hara (Hydrocharitaceae) Phulke S Plants is used as green manure



During the field survey, ethnobotanical data of 55 species of plants belonging to 36 families have been collected. Among the documented useful species, the families Asteraceae and Cyperaceae were most frequently represented with a total of 5 species each, followed by Polygonaceae 4, Amaranthaceae 3  and others with less than 3 species. The data also indicate that 31 species were used to treat various alignments, 20 for human food, 14 for fodder, 9 for manure, 7 for animal foods, 3 as piscicidal agents, 3 as insectisides and 1 for mat making (Table 1). The data on the medicinally important plants indicate that 11 species were used to treat gastrointestinal disorders, 9 for fever, cough, headache and respiratory  ailgments, 8 for  dermatological illnesses, 5 for genito-urinary complains, 6 for illness of  skeleto-muscular, 6 for cuts and wounds, 1 for  cardiovascular complaints  and diseases of blood, and 2 for other diseases (Table 2).
TABLE 2 Disease Categories of Medicinal Plants
Disease category                                   
               Medicinal Plants
Cardiovascular complaints  and diseases of blood Capsella bursa-pastoris   
Cough, fever, headache  and respiratory  ailgment Ageratum houstonianum, Artemisia indica, Centella asiatica, Eclipta prostrata, Equisetum debeli, Justicia diffusa, Nelumbo nucifera, Sagittaria gyanensis, Solanum nigram, 
Dermatological illnesses Alternanthera sessilis, Amaranthus spinosus, Artemisia indica,Cannabis sativa, Centella asiatica, Persicaria barbata, Ranunculus scleratus,  Rumex nepalensis,
Gastrointestinal  disorders Ageratum houstonianum, Alternanthera sessilis, Argemone maxicana, Cannabis sativa, Cyperus rotundus, Ipomea aquatica, Nelumbo nucifera, Nymphoides indica, Oxalis corniculata , Plantago major, Trapa bispinosa,
Genito-urinary complains Ageratum houstonianum,Ipomea aquatica, Persicaria hydropiper, Plantago major,Utricularia bifida
Illness of  skeleto-muscular Chenopodium album, Cyperus rotundus, Eclipta prostrata, Equisetum debeli, Trapa quadrispinosa, Urena lobata,
cuts, wounds Ageratum conyzoides, Eclipta prostrata, Eupatorium adenophorum, Plantago major, Rumex nepalensis,Urticularia aurea
Other uses ( pain etc) Cannabis sativa, Solanum nigram,





The present study indicates that the studied areas are very rich in wetland plant biodiversity and indigenous knowledge. The local people are dependent on these species not only for domestic uses (especially food, manure, raw-materials), but also to cure various diseases. According to collected information, only small quantities of some species are collected and sell in market. However, there is possibilities to enhance the income of the local communities, if properly managed the habitats and potential species in an integrated manner with the involvement of local people in planning and management of the resources. So it is recommended to initiate the activities, such as  inventory of useful species, habitat characteristics, identification of potential species for various economic uses and formulation and implementation of plan of actions taking consideration of the needs of people and sustainable management of the wetlands.
 
When questioned about the changing status of the existing plants, our respondents mentioned that the alien and invasive species are spreding very fast in the water bodies impacting on the growth of the native species. Some species, especially species of Nelumbo, Nymploides  and Trapa are declined in abundance during the last decade. Siwakoti (2006) has also reported similar encroachment and spreading in the wetland sites of the Terai by alien and invasive species. Priority  should be focused on the conservation of the valuable native species and  their habitats with the integrated management measures.
 
Another interesting findings of the present study also revealed that knowledge related to the therapetic uses of plants were richly prevelent than other  used categories (Table 2). The uses of plants for treatment of physical ailments are benificial and effective as claimed by both the practitioners and users. Enquiries in the studied areas also revealed a number of negative impacts such as abdominal pain, vomiting, suffocation and burning of stomach  as a result of taking the plant or parts of the plant as drugs. However, screening of chemicals and pharmacological aspects of the medicinal plants is needed for  the determination of effectiveness of the  plants, Therefore, one of the strategies needs to emphasis is to implement the activities to conduct pharmacognostic and pharmacological studies of the useful species to ascertain their therapeutic properties. .

Conclusion
The present trend of  uses of wetland plant diversity in the studied areas indicate that the uses of plants and traditional  practices will continue to play a significant role in the socio-cultural life of these village communities. But the trend of decline of the abundance of some very useful native species, increase of unsustainable anthropogenic practices and enchrochment and spreading of invasive species show that action for conservation is urgently needed. Therefore, priority should be given to implement conservation activities with integrated approach for sustainable development.
Acknowledgements
We express our thanks to the inhabitants of  the study areas who were willing to share with us the knowledge about their wetland plants. We would also like to thank Dr. John F. Edington, Former Director of Environment Studies, University of Wales, Cardiff, U.K., Dr. N. Ghandi, Harvard University Herbaria, USA, and  Profs. P.K. Jha, R.P. Chaudhary and K. K. shrestha, Central Department of Botany, Tribhuvan University, Kathmandu, Nepal  for constant encouragement.

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