NEWS

MEETING REPORT

Vetiver system ecotechnology for water quality improvement and environmental enhancement

Vetiver, Vetiveria zizanioides L. Nash, a highlighting that vetiver (i) is native to vetiver hedges to mark out farm bounda- native grass of India has traditionally hygro-environment such as wetland, ries in Karnataka (India), to the World been in use in India for contour protec- lagoon and bog, (ii) is extremely tolerant Bank-supported follow-up studies on tion and essential-oil production. Taking to drought as well as waterlogged/ grass vis-à-vis its multifari- clues from its traditional usage in envi- submergence conditions, (iii) is effective ous applications in phyto-remediation, ronmental protection, The World Bank for soil and water conservation, and (iv) reclamation of mine dumps, and its abil- initiated several projects in India in is endowed with excellent biological ity to filter toxins before they enter the 1980s for systematic development of features to ameliorate wastewater and water-table. Vetiver Grass Technology (VGT), now pollution mitigation. The conference was In his opening lecture ‘Vetiver grass – popularly known as Vetiver System (VS). inaugurated by the Patron of The Vetiver a world technology and its impact on Large-scale developments have since Network, HRH Princess Maha Chakri water’ Richard G. Grimshaw (USA) des- taken place in the advancement of VS in Sirindhorn of Thailand, and was attended cribed how vetiver has developed as a environmental protection1; new avenues by over 230 delegates representing 28 world technology over four phases of have opened up over the past 15 years2. countries. There were 13 plenary presen- application: soil and water conservation The VS is emerging as a panacea to a tations covering eight sub-themes, and 46 in poor rural areas; infrastructure stabili- host of environmental problems. It is a oral presentations, including four King of zation; rehabilitation of difficult and low cost, extremely effective system that Thailand Vetiver Award presentations4. often polluted sites; and water quality offers proven solutions for soil and water Also, an exhibition on VS-based eco- enhancement and site rehabilitation in conservation, wastewater treatment, em- technologies and products in the form of relation to industry and intensive agricul- bankment stabilization, flood control, posters and demonstration stalls was ture. He admitted that introduction of disaster and pollution mitigation, agro- arranged at the conference site by vari- VS-based new technology was slow, but forestry management, and many other ous scientific agencies and entrepre- it has since made steady progress. environment-friendly applications being neurs. Further, the organizers had also Paul Truong (Australia) in his talk on used in over 100 countries3. The VS for arranged a one-day study tour for an on- ‘Vetiver system for water quality imp- wastewater treatment is a new and inno- site live demonstration of VS projects rovement’, dwelt upon the significance vative phyto-remedial eco-technology, ranging from applications of vetiver in of the VS in addressing the imminent which has the potential to meet all the garbage landfill site management, land global crisis of water shortage. Pinpoint- right criteria necessary for environmental slope stabilization and slope aforestation, ing the ability of vetiver grass to with- enhancement. It is a natural, green, sim- and water and vegetation rehabilitation at stand highly adverse climatic and edaphic ple, practicable and cost-effective solu- an ecological park. conditions, including elevated levels of tion, and its by-products offer a range of Sumit Tantivejkul, Secretary General, salt, acidity, alkalinity, sodicity as well uses in handicrafts, animal feed, fuel and Chaipattana Foundation, Bangkok in his as a whole range of heavy metals, and construction applications. Morphological keynote address on Thailand’s experience also its ability to absorb and tolerate and physiological attributes of vetiver with respect to vetiver and water, under- extreme levels of nutrients, he advocated grass, its strong, deep penetrating (Figure pinned the significance of vetiver grass that vetiver is ideally suited for treating 1 a), aerenchymatous (Figure 1 b) root for its deep penetrating root system that contaminated and polluted wastewater system, unusual ability to absorb and forms an underground wall barrier and from industries as well as domestic dis- tolerate extreme levels of nutrients, agro- helps to filter silt and maintain topsoil. charge. Highlighting morphological and chemicals and heavy metals make it an He stressed that exhaustive experimenta- physiological attributes of vetiver sup- ideal system for environmental enhance- tion on vetiver system covering over 30 ported with empirical observations, he ment through appropriate interventions initiatives by the Royal Development emphasized that the VS can help manage in the treatment regime. Study Centres has since been imple- wastewater quantity through seepage The 3rd International Conference on mented all over Thailand by the Gov- control, and its quality by trapping sedi- Vetiver and Exhibition (ICV-3), was orga- ernmental agencies for realization of bene- ments and particles, tolerating and absor- nized in Guangzhou, China during 6–9 fits of vetiver system in soil and water bing pollutants, heavy metals, and deto- October 2003 by the Guangdong Academy conservation, forest rehabilitation and xification and breakdown of industrial, of Agricultural Sciences, in association restoration of degraded soil, as well as mining and agrochemical residues, dur- with South China Institute of Botany environmental protection of water bodies ing land irrigation and under wetland (Chinese Academy of Sciences), South from effluent contamination and garbage conditions. Through another presenta- China Agricultural University and Guang- decomposition. John Greenfield (New tion he pointed out that vetiver, on ac- dong Association of Grass Industry and Zealand) giving a historical perspective count of its trapping/absorption capacity Environment. The theme of the confer- of ‘Advance of scientific research on of nutrients, sediments and agrochemi- ence ‘Vetiver and water’ was truly em- vetiver system’ traced the rediscovery of cals, can help stabilize otherwise fragile bodied in the conference deliberations, the versatile VS, from realization of drain banks made up of acid sulphate

CURRENT SCIENCE, VOL. 86, NO. 1, 10 JANUARY 2004 11 NEWS

a b c

d e

f h

g

i

Figure 1. Eco-technological applications of the vetiver system. a, A 3.4 m long fibrous root system after 275 days of growth, from China, b, Transverse section of mature root showing schizogenous aerenchymatous cortex suitable for waterlogged condition and well-developed phloem for essential oil. c, Garbage landfill site in China covered with thick rubber sheet on top and earthen slope planted with vetiver for slope stabilization and leachate absorption. d, Slide-slope protection by vetiver along the railway line in Madagascar – proper drainage and suitable for sustainable utilization of the vetiver system. e, Tea bushes grown between vetiver hedge rows in China to advance tea growth and tea quality. f and g, Restoration of water channel in the ecological park – contaminated wastewater channel (f) and ecologically restored water channel after vetiver plantation (g). h, Natural water ponds near Lucknow. (Below) With eutrophicated water having algal bloom. (Top) With vetiver purified water supported with green vegetation. i, Vetiver floating pontoons for wastewater treatment in a sewerage pond in Australia.

12 CURRENT SCIENCE, VOL. 86, NO. 1, 10 JANUARY 2004 NEWS soils highly loaded with heavy metals, wan Mahisarakul (Bangkok) showed that gesting that in addition to mechanical iron, aluminum and other metal concen- the vetiver root could grow luxuriantly characteristics, the root growth curve, trations, thus facilitating control of channel and tolerate contamination of agricultural three-dimensional root net, capacity to bank erosion. Cameron Smeal (Australia) residues, including endosulphan in the re-vegetate on slope are the important pointed out that treating effluents with garbage-fill site. Xuhui Kong (China) contributing factors in vetiver eco-engi- vetiver in industrial wastewater is actu- showed that vetiver–bamboo floats effi- neering anti-scour and anti-slide applica- ally a ‘recycling process’ and not a treat- ciently absorb heavy metals such as Zn, tions. Ping Zhang and Bo Huang (China), ment process per se, as in the process of Cu, Pb, Hg as well as nitrates from the through their independent studies, pro- ‘treatment’, the vetiver plant absorbs wastewater, thus helping the purification vided successful examples of quarry/ essential plant nutrients such as N, P and of eutrophicated water accumulated on karst stony slopes re-vegetation using cations, and stores them for other uses. pig farms. Based on wetland microcosm complex vetiver eco-engineering tech- In Australia, with large-scale planning test Xuerui Lin and Wensheng Shu (China), nique, where vetiver plantations could be this recycling plant is anticipated to pro- from their two independent studies, sug- established in mechanically designed plant- vide high nutrient material for animal gested that vetiver grass-constructed ing traps on quarry slopes. Surapol San- feed, mulch for gardens, manure for or- wetlands have a great potential in the guankaeo (Bangkok) provided an account ganic farming and organic source for treatment of nitrate-concentrated landfill of successful application of the VS in composting. leachate and acid mine drainage from slope stabilization along the mountain Ralph Ash (Australia) presented an lead/zinc mine tailings. Stefanie Wagner roads in the northern, northeastern and innovative example for development of a (Germany) showed that vetiver has tre- southern regions of Thailand. VS prototype for sewerage treatment mendous capacity for recovering N and P Le Viet Dung (Vietnam) showed that schemes in Australia. He suggested that from wastewater and polluted water establishment of vetiver hedge rows has as phyto-remedial technology for effec- loaded with excessive N and P supply, provided effective soil-erosion control tive removal of nutrient loads in sewer- and can withstand N and P at rates of measure and bank stability in Mekong age disposal ponds, vetiver when planted 10,000 kg/ha/yr and 1000 kg/ ha/yr res- river delta against current and wave ero- as floating pontoons (Figure 1 i) as well pectively, suggesting that vetiver is suit- sion caused by motorized boats in fresh- as on contours, helps reduce nutrient able for treating wastewater and other water, brackish water, rivers and canals, load to a great extent making the sewer- polluted materials having high N. on alluvial as well as highly acid sulphate age water suitable for subsequent irriga- Based on analysis of hydraulic retard- soil. Tran tan Van (Vietnam), through his tion purposes3,5. Barbara Hart (Australia) ness, sedimentation trap and plant sub- vetiver trial and demonstration project, suggested that septic-tank effluent hydro- mergence characteristics of vetiver hedge showed that both local farmers and engi- ponic vetiver treatment helps remove planting, Oscar Metcalfe (Australia) sug- neers have adopted the VS as their pre- nitrate contamination thus mitigating gested that vetiver hedges significantly ferred option for coastal dune and road- ground water pollution by septic-tank reduce the effective flow area of a chan- batter stabilization, stream-bank erosion effluents. Ian Percy (Australia) showed nel; dense planting of vetiver in deep un- and fish-pond stabilization. M. Nazrul that landfill leachate run-off, low in submerging flows show high hydraulic Islam (Bangladesh) provided a case ex- heavy metals but high in salt and nutri- resistance, and rows of vetiver are more ample of successful introduction of veti- ents, could be recycled through irrigation suited to steep slopes/highly erosive flows ver in coastal polders over a 87 km long of garbage mounds with vetiver grown where sedimentation is unlikely. stretch in Bangladesh, as a cost-effective thereof, thus saving the adjoining areas Giving an overview of the VS in slope measure to maintain the coastal em- from being contaminated with landfill– stabilization, Diti Hengchaovanich (Bang- bankment system. O. Bababola (Nigeria) leachate discharges. Alison Vieritz (Aus- kok) opined that ever since the bench- showed that planting of vetiver strips tralia) showed that vetiver implicit a high mark experiments on vetiver root stren- almost completely checked soil and run- nutrient uptake that makes it ideal for gth conducted in 1996, the VS has off water loss in the eroded soils and wastewater purification in the effluent evolved to become an important bioengi- consistently enriched the protected soil irrigation schemes. neering tool having global acceptance. with nutrients. Liyu Xu (China) furnished Henping Xia (China) based on his As a follow-up of hard experimental case examples where the VS has been findings on constructed vertical flow background, vetiver has made headway found to be effective in agricultural utili- wetlands, depicted that vetiver is highly in cost-effective stabilization of karst zation of red soil, soil and water conser- efficient in purification and refinement stony slopes in high-altitude region, as vation in orchards, and in advancing tea of wastewater produced from the oil well as in re-vegetation of barren quarried growth and tea quality (Figure 1 e). refineries. He, however, emphasized that face in China; river bank stabilization in In addition to the above-mentioned efficiency of vetiver in water refinement fresh- and brackish-water environment in specific eco-technological applications, was high with the fresh plantation, but Vietnam and China; beach protection other aspects discussed at the conference gradually decreased with the passage of in Senegal; coastal polders stabilization included the VS for wasteland reclama- time. Thares Srisatit (Bangkok) pre- in Bangladesh, and in providing channel tion, agriculture production and agrofor- sented findings on chromium removal and flood control measures in Australia. estry; adaptability of vetiver to flooding, efficiency of vetiver from tannery-waste- Chengchun Ke (China) provided an ex- medicinal vetiver, pesticidal vetiver, water constructed wetlands, and arsenic perimental account of engineering design nutritient contents and digestibility of removal from experimental pots. Study- samples for appropriate application of vetiver grass, the VS entrepreneurship, ing the root growth pattern elucidated eco-engineering technology for steep and other uses of vetiver in cottage in- through radioactive labeling uptake, Jitti- slope and river-bank stabilization, sug- dustry/handicrafts and utilization of

CURRENT SCIENCE, VOL. 86, NO. 1, 10 JANUARY 2004 13 NEWS vetiver grass raw material in industrial observed by the present authors in a be occurring only in India. With con- applications. U. C. Lavania (India) pre- natural . A field observation of certed efforts exercised, it is possible to sented an overall account of vetiver oil, natural flora of two adjoining ponds with identify/develop designer plant/root types embracing its processing, composition, and without vetiver plantations, shows of vetiver suiting specific applications, economics and perfumery applications. that the stagnant water in the former is ranging from vetiver for its essential oil Seshu Lavania (India) dwelt upon the clean, supporting growth of aquatic to vetiver for soil/water conservation and morpho-anatomical and topographic chara- plants and in the latter it is eutrophicated, detoxification. Therefore, it is time that cteristics of vetiver root-system to identify supporting algal bloom (Figure 1 h). India rejuvenates its initiative and em- root ideotype suitable for need-specific Although there were no specific rec- barks upon optimum utilization of this applications. Y. Vimala (India) presented ommendations, it was duly emphasized low-cost environment-friendly natural physico-chemical potential of vetiver in that the VS has come to an age as a low- technology. wetland soil reclamation. cost eco-technology measure for a host In general, the ICV-3 was well organ- One of the important presentations of environmental problems. However, in ized. The first two conferences ICV-1 made at the conference was by Diti view of high absorption potential of (1996) at Chiang Rai7 and ICV-2 (2000) Hengchaovanich (Thailand) about ‘Veti- vetiver not only for nutrients but also for at Cha-am1, both in Thailand were an ver victorious: the systematic use of toxic residues, including agrochemicals, eye-opener that portrayed bioengineering vetiver to save Madagascar’s FCE rail- heavy metals and industrial effluents potential of vetiver grass. The third one way’. Vetiver plantation could help restore reaching the upper ground parts, the provided the means and ways for envi- the 163 km train route in Madagascar, question remains as to where to dis- ronmental enhancement, more particu- severely hit by over 280 landslides pose/make best use of raw material con- larly water quality improvement and caused by two cyclones in 2000 (refs 3 taining toxic substances. The present mitigation of pollution. In fitness to the and 6). An innovative ‘vetiver-for- authors are of the opinion that as a part progress made, newer avenues opened vetiver loan/reimbursement’ plan and a of integrated post-management of the VS for social and economic implications of ‘modular cropping system’ that facili- eco-technology, it may be appropriate to the VS in future and it was suggested tated dissemination and implementation utilize the vetiver containing that ICV-4 be organized on the focal with farmers over a three-year period has toxic chemicals/substances through its theme ‘Vetiver and people’. helped establish reduction of erosion fixed applications in an eco-friendly damage, strengthening of slopes and infra- manner. The two possible solutions could structure along the line. Success achie- be through utilization of such vetiver 1. Lavania, U. C. and Lavania, S., Curr. Sci., 2000, 78, 944–946. ved by vetiver intervention not only grass biomass for vetiver ceramic pots 2. Xu, L., Fang, C., Wan, M. and Chirko, P. helped in restoration of the railway line and use of vetiver grass ash as cement- (eds) Vetiver System and its Research and but also improved soil fertility of the replacement material that meets all envi- Applications in China, Ya Tai Int. Publ. stabilized slopes for aforestation with ronmental and engineering pre-req- Co. Ltd, Hongkong, 2003, p. 127. fruit trees (Figure 1 d). Another success- uisites. Supporting evidences towards 3. Truong, P. and Xia, H. (eds) Proceedings ful example witnessed by the delegates such a utilization were presented sepa- of the Third International Conference on during the conference on the study tour rately by Varunee Thiramongkol and Vetiver and Exhibition, China Agricultural was the management of 20 ha garbage Pichai Nimityongskul (Thailand). Press, Beijing, 2003, p. 614. landfill project site, Datanshan Garbage Vetiver is native to India, its environ- 4. King of Thailand Vetiver Awards Winners’ landfill, located in Huangpu district, mental applications for soil and water papers, ORDPB, Bangkok, Thailand, 2003, p. 58. 20 km east of Guangzhou town. Vetiver conservation are in traditional practice 5. Truong, P. and Hart, B., PRVN Tech. Bull. plantations along the slopes of the land- since ancient times. Also, systematic No. 2001/2, ORDPB, Bangkok, Thailand, fill site have not only stabilized the efforts to develop vetiver grass technol- 2001, p. 24. slopes, but controlled leachate outflow ogy for mitigation of soil erosion and 6. Hengchaovanich, D. and Freudenberger, by on-site absorption by vetiver (Figure water conservation were first initiated in K. S., PRVN Tech. Bull. No. 2003/2, 1 c). Another demonstration about the India, but we missed the due initiative. ORDPB, Bangkok, Thailand, 2003, p. 16. potential of the VS in wastewater purifi- Several countries on the other hand, tak- 7. Lavania, U. C. and Sharma, J. R., J. Med. cation was in the water streams of Ying- ing cues from the Indian initiative, ex- Aromat. Plant Sci., 1996, 18, 322–326. zhou ecological park located in Xiaozhou tensively implemented environmental village, Xinjio town, Haizhu District applications of this grass. In particular, Guangzhou. Water streams in this eco- Thailand, Australia and China have since U. C. Lavania*, Central Institute of logical park become severely polluted by made significant strides in applications Medicinal and Aromatic Plants, Lucknow tidewater from the Pearl river. Vetiver and advancement of the VS eco- 226 015, India; Seshu Lavania, Depart- plantation in the water channels of the technology. India is the centre of origin ment of Botany, Lucknow University, park has helped rehabilitation and purifi- of vetiver, where this species is enriched Lucknow 226 007, India and Y. Vimala, cation of the otherwise contaminated with tremendous genetic diversity in Department of Botany, C.C.S. Univer- channel water, making it suitable for reproductive behaviour, physiological sity, Meerut 250 005, India. growth of natural flora (Figure 1 f and g). and morphological characteristics. Also, *For correspondence. A corollary to such a situation has been natural seed setting in vetiver is known to e-mail: [email protected]

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