the vetiver system workshop ppt/kuw-ppt02.pdfthe basic vetiver grass technology the vetiver grass...
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THE VETIVER SYSTEMVETIVER GRASS
TECHNOLOGYTechnology Characteristics
THE VETIVER SYSTEMVETIVER GRASS
TECHNOLOGYTechnology Characteristics
Richard GrimshawThe Vetiver Network
ContentsContents
• Background
• Morphological characteristics
• Physiological characteristics
• Applications
• Summary
BackgroundBackground
• Characteristics of an ideal grass for bio-engineering
• Vetiver Grass - Vetiveria zizanioides
•The Basic Vetiver Grass Technology
•Origin & genetic characteristics
•Soil conservation methods
Characteristics of an Ideal PlantCharacteristics of an Ideal Plantfor Bio-engineeringfor Bio-engineering
• Its seeds should be sterile, and the plant shouldnot produce stolons or rhizomes that couldbecome invasive or weedy.
• Its crown should be below the soil surface sothat it can resist fire and overgrazing.
• It should be capable of forming a dense, groundlevel permanent hedge, performing as aneffective filter, preventing soil loss from runoff.(Apparently only clonal material seems to beable to grow ‘into’ each other to form such ahedge).
• It should be perennial and permanent, capableof surviving as a dense hedge for decades, butonly growing where we plant it.
Characteristics - ContinuedCharacteristics - Continued• It should have stiff erect stems that can withstand a
water flows of at least 1 cusec (.028 cumecs) 12inches (0.3m) deep.
• It should exhibit xerophytic and hydrophyticcharacteristics if it is to survive the forces ofnature.
• It should have a deep penetrating root system,capable of withstanding tunneling and crackingcharacteristics of soils. The roots should penetratevertically below the plant to at least three meters.
• It should be capable of growing in extreme soiltypes, regardless of nutrient status, pH, sodicity,acid sulphate or salinity, and toxic minerals. Thisincludes sands, shales, gravels, even more toxicsoils and mine tailings.
Characteristics - ContinuedCharacteristics - Continued
• It should be capable of developing new rootsfrom nodes when buried by trapped sediment,and continue to grow with the new groundlevel, to eventually forming natural terraces.
• It should not compete with the crop plants it isprotecting.
• It should be free of pests and diseases.• It should be capable of growing in a wide
range of climates -- from less than 300 mm ofrainfall to over 6,000 mm -- from temperaturesof -15º C to more than 55º C. It should be ableto withstand long and sustained droughts (>6months).
Characteristics - ContinuedCharacteristics - Continued
• It should be inexpensive and easy toestablish as a hedge and easilymaintained by the user at little cost.
• It should be easily removed when nolonger required.
Vetiver grass has all thesecharacteristics.
The Basic Vetiver GrassThe Basic Vetiver GrassTechnologyTechnology
The Vetiver Grass Technology (VGT), in its mostcommon form, is simply the establishment of anarrow (less than 1 meter wide) live stiff vetivergrass barrier, in the form of a hedge, across theslope of the land. When applied correctly thetechnology is effective on slopes from less than1 to over 100%. A well-established vetiver grasshedge will slow down rainfall runoff, spreading itout evenly, and will trap runoff sediments tocreate natural terraces. In addition its massiveroot system will increase the shear strength ofsoil (thus providing improved stability of soils onsteep slopes).
• Native of India
• Promoted in the 1980´s by World Bankfor soil conservation
• Southern India, sterile, genotype usedin more than 120 countries
• DNA typing shows conformity ofprincipal genotypes globally
Origin and Genetic CharacteristicsOrigin and Genetic Characteristics
Soil Conservation MethodsSoil Conservation MethodsCONSTRUCTED VEGETATIVE
Run-offRain
Vegetative hedges
Bank 'melts'
Earth bank or bund
5 meters
Run-off
Earth banks
Rain
Waterway
Naturalterrace
50 cm
• Erect and stiff stems
• Deep, dense and penetrating root system
Morphological characteristicsMorphological characteristics
2m tall hedgerow
Vetiver
Erect and Stiff StemsErect and Stiff Stems
One yearplants
3m deeproots
Deep, Dense and Penetrating Root SystemDeep, Dense and Penetrating Root System
• Soil conservation
• Resilient to strong water flows
• Hedgerow barrier
• Nutrient filtration
Physiological Characteristics -1Physiological Characteristics -1
YoungVetivertrappinggravel
Soil Conservation Soil Conservation
VetiverOther grass
Resilient to Strong Water FlowsResilient to Strong Water Flows
Vetiver
Hedgerow BarrierHedgerow Barrier
Vetiver
Nutrient FiltrationNutrient Filtration
• Fire
• Water logging, inundation
• Salinity
• Acidity/Alkalinity
• Aluminium and Manganese
• Heavy metals
• Herbicides/Pesticides
Tolerant to:
• Cold and hot weather
Physiological Characteristics - 2Physiological Characteristics - 2
-140Ckilled topgrowth
Fullrecovery3 monthslater
Frost ToleranceFrost Tolerance
Vetiver canbe burnt
Goodrecovery5 monthslater
Fire ToleranceFire Tolerance
Vetiver
Water Logging ToleranceWater Logging Tolerance
Salt Tolerance - 1Salt Tolerance - 1
Mangrovestands
Fiji
Vetiver
Mangrovefern
Marine couch
Mangrove
Salt Tolerance - 2Salt Tolerance - 2
Erodibleacid sulfatesoilCostalQueensland
Oneyearlater
Twoyearslater
Acid Soil ToleranceAcid Soil Tolerance
Atropine Diuron
Vetiver
Phragmites
Herbicide ToleranceHerbicide Tolerance
•Vetiver Grass - A Hedge Against Erosion. John C.Greenfield
•Vetiver Grass - An Essential Grass for theConservation of Planet Earth. John C. Greenfield
•A Look See at Vetiver. P.K. Yoon
•Vetiver System 2005 - (CD Rom) TVN
REFERENCESREFERENCES
www.vetiver.org
Paul Truong
Michael Pease
AcknowledgementsAcknowledgements