TARGET MARKET: Jabatan Kerja Raya (JKR), Jabatan Pengairan dan Saliran (JPS), Indah Water – Kualiti Alam, State Governments – Highway Authorities, KTM – Municipal Councils, Agricultural Authorities – Golf Courses and Recreational Areas, Civil Engineering Firms – Environmental Engineering, Firms, Landscaping Companies – Water / Wastewater Treatment Companies, Plantation and Farms – Construction Companies,
AREAS OF APPLICATION:
1. BIOENGINEERING APPLICATIONS:
The “Vetiver System” is an effective, low cost, multifunction bioengineering technology that protects infrastructure and wetlands by enhancing control over soil and water management. Bioengineering is a method of design and construction using natural structural components in combination with vegetation for erosion control, water quality and habitat restoration. As Vetiver can be used to protect the environment (soil, water and air) before deterioration occurs, we will utilize it as the prevention mechanism. In this regard, the vetiver system can be employed in the followings:
Erosion Control And Sediment Trapping: The mature hedge will form a living porous barrier which slows and spreads runoff water. As water flow slows down, its erosive power is reduced and any eroded material is trapped by the hedges. Therefore vetiver would be very effective in stabilising table drains, gullies, creek banks and other drainage structures.
Slope Stabilization: This is where vetiver excels because of its long roots. As such, it should ideal for helping stabilizing cuttings and fills on highways, railways and dame.
Flooded Structures Protection: High flow velocity during flood period can cause extensive damage to structure. Vetiver System provides a very effective measure against flood erosion. When planted in row vetiver plants will form thick hedges and with their stiff stems these hedges can stand up to at least 0.6m, forming a living barrier which slows and spreads runoff water. If properly laid out these hedges can act as very effective diversion structures spreading and diverting runoff water to stable areas or proper drains for safe disposal.
Stream and Channel Bank Stabilisation: When planted correctly vetiver is very effective in the stabilisation of stream, river and channel banks.
Concrete and Rock Structures Protection: The combination of the deep root system and thick growth of the vetiver hedges will protect the ground surface next to the concrete structures such as culvert inlets and outlets, gabion structures or other solid barriers and from scouring and erosion by high velocity flow. When planted upstream from the inlets vetiver hedges also the culvert free from sediment deposition by trapping the coarse sediment outside the culvert where it can be easily cleaned if required.
Protection of Concrete/Gabion structures: The combination of the deep root system and thick growth of the vetiver hedges will protect the ground surface next to the concrete structures such as culvert inlets and outlets, gabion structures or other solid barriers from scouring and erosion by high velocity flows. When planted upstream from the inlets vetiver hedges will not only protect the inlets but they also trap the sediment outside the culverts where it can be easily cleaned if required.
Rairoad Protection and Stabilization
Railroads often have the need for protection and stabilization. Vetiver System has proved extremely effective under varied conditions for this task.
Dams, Reservoirs and Ponds Stabilization
Because vetiver grass can be submerged in water and at the same time stabilize slopes, Vetiver System is very effective for applications relating to reservoir drawdown areas, dam walls, and pond banks.
Vetiver System has proven very effective and low cost to stabilize highway batter slopes and underpass drainage drainage structures and approaches. The key to success is good quality planting material and good application on site. Highway cut and fills are often serious sources of point source sediment erosion in a river basin or watershed.
River and stream bank erosion control
Vetiver Systems are extremely effective for protecting river banks against erosion from currents and wave action. It is also affective for the protection of river associated structures such as bridge abutments, wiers etc. where soil and concrete interface
Rural Roads Protection
Vetiver System provides excellent protection to rural roads. Particularly it protects road shoulders, road batters, culverts, bridge abutments, low level river crossings. As a result of this protection, road maintenance requirements are less frequent and costs are reduced.
Most of the major utilities need protection from erosion and vandalism. Vetiver Systems provides a good alternative. It is tough, does the job and needs little maintenance.
Carbon Sequestration: As evidence mounts on the effect of the increased amounts of carbon dioxide on global warming, the world looks for alternative methods to mitigate the problem. Because of its longevity and extraordinary root mass, Vetiver is becoming one of the leading contenders for carbon sequestration. This bioengineering application of Vetiver accomplishes the long-term storage of carbon dioxide or other forms of carbon through biological processes. With Vetiver, carbon products are extracted from the atmosphere through photosynthesis and stored permanently in its root mass.
Vetiver System makes an excellent application for stand alone urban landscaping or for composite landscaping that integrates slope stability with beautification. Because it has such a wide range of location and application it can be used both in, near or far from water surfaces.
When properly laid out, maintained and trimmed vetiver hedges can be very effective in erosion control as well as an attractive component of the landscape. Examples of the various uses of vetiver in landscaping are the followings:
As a Decorative Hedge: Vetiver is used as a decorative hedge on the roundabouts.
For Dual Purpose in Beautifying the Landscape and Environmental Protection: Vetiver hedges have been used to stabilize soils and control erosion in amenity sites such as golf courses and water park recreational areas.
For Reservoir Landscaping: Since reservoirs have become recreation sites and efforts to vegetate the banks have been unsuccessful in the past, vetiver, by virtue of its resistance to surviving in the water for a period of time, has been used to be grown on the bare banks of a reservoir.
Biological pest control: Research conducted showed that of the 79 species of insect found on the vetiver rows, only four attacked young vetiver leaves. However, due to their small population the damage was minimal. On the contrary, 30 other species found in the vetiver rows are considered beneficial insects, as they are the all-important enemies of garden, agriculture and forest pests. This indicates that an integrated pest management scheme will be put into operation when vetiver is introduced to a new environment.
2. PHYTOREMEDIATION APPLICATION:
Phytoremediation is a method of environmental protection using plant, a natural product, to contain, reduce and/or eliminate pollutants in contaminated water and land. Phytoremediation is an interesting alternative to current environmental cleanup methods that are energy intensive and expensive. An important advantage of harvested vetiver is that it is not considered hazardous waste, unlike hyperaccumulator residual. It can be used safely for bioenergy production, compost or even as material for handicrafts. As Vetiver can be used to cure environmental problems that have already occurred, we will utilize it as the curing mechanism.
Two approaches are being made to make use of vetiver in phytoremediation, namely:
RECLAMATION OF DETERIORATED SOILS
Deteriorated soils are soils which possess poor physical and chemical properties as the result of natural phenomena. Such soils are unproductive, giving poor yields to crops grown on them even with proper agricultural practice such as providing fertilizer, irrigation and pest control. In addition to these naturally-caused deteriorated soils, crop yields are also low if fertility and moisture are not adequate. Improper land management also contributes to poor yield as the result of degradation of soil properties, especially in the decline of organic matter.
REHABILITATION OF CONTAMINATED SOILS AND WATER
One of the causes of environmental degradation is pollution due to the presence of pollutants in soils and water. The extent of the pollution in both the developing and developed countries is quite significant owing mainly to uncontrolled discharge of pollutants from various sources, including chemical by-products, heavy metal and other industrial wastes, pesticides, and fertilizer residues, domestic garbage and landfill leachate, etc. into the environment. Such environmental degradation has been a major concern for the public and private environmental agencies worldwide. Various control measures have been attempted, but their high cost is a major drawback, especially in developing countries. Thus there is clearly a need to seek certain low-cost technology, such as phytoremediation, to deal with the ever-increasing levels of pollution.
Rehabilitation of Contaminated Soils:
Vetiver Systems is a proven method of rehabilitating land of almost any condition. It is thus ideal for rehabilitating farm land, gullies, degraded slopes, and mine tailings. Mines and quarries often comprise oif material that is hostile to plant growth and at the same time is a point source of toxic waste that seeps into streams and that contaminate river basin waters. Identify the point source problem, and Vetiver System will go a long way at fixing the problem. Vetiver grass is extremely tolerant to the heavy metals in most of these sites and will hold them in its roots. At the same time it will prevent sediment that contains these pollutants from entering the streams and rivers. Because of the good ground cover vetiver will also prevent wind blown dust from these sites from effecting nearby populations.
Vetiver is highly successful in the rehabilitation of both old and working quarries where very few species can be established due to the hostile environment. Vetiver is able to stabilise the lose surface first so other species can colonise the areas between hedges later.
Mine tailings are not only a source of sediment but also produce toxic effluents. Most plants have difficulty establishing on these toxic soils. Vetiver can deal with both very well.
Treatment of Landfills or Garbage Dumps:
One of the main environmental concerns associated with landfills is the generation of leachate from waste decomposition. (Leachate is the liquid that drains or ‘leaches’ from a landfill; it varies widely in composition regarding the age of the landfill and the type of waste that it contains. It can usually contain both dissolved and suspended material).
Landfill leachate usually contains high concentrations of heavy metals that are seriously harmful to the environment and human health. The movement of these contaminated materials from these sites needs to be adequately controlled. Vetiver System can help prevent the movement of this leachate
Vetiver is the proven solution to control the spreading and contamination of leachate from both fresh and old landfill. The very high level of tolerance to heavy metals such as As, Cd, Cr, Ni, Ca, Pb, Zn, Se and Hg and agro-chemicals reported above indicate vetiver grass is most suitable for use in the rehabilitation of such contaminated sites. Vetiver will act as a pioneer plant to decontaminate and reduce surplus leachate on landfill sites and will help in improving the environment.
Rehabilitation of Contaminated Water (Wastewater Treatment):
Applying the Vetiver System (VS) to wastewater treatment is an innovative phytoremediation technology that has tremendous potential. Vetiver System is a very effective method of treating polluted water, domestic effluent, industrial wastewater and landfill leachate. Application of the Vetiver System for wastewater treatment has the potential to meet the global water crisis. It is a natural, green, simple, practicable and cost effective solution.
Vetiver was tried in China for the removal of P and N. It was found that after three weeks, virtually all P was sucked up, while 74% of N was removed. Experiments conducted in Thailand on wastewater indicated that vetiver had the ability to uptake heavy metals and accumulated in the shoots and roots. Such experiments indicated the possibility of vetiver as a biological wastewater treatment.
Sewage Effluent Treatment
Sewage, wherever you may live, needs to be recycled. This can occur by means of expensive sewage work systems or by natural biological purification. The utilization of Vetiver grass beds is a unique and innovative technology for sewage treatment.
The ability of Vetiver grass (Vetiveria zizanioides) to absorb harmful elements, bacteria and nutrients should be of great concern to all, because fresh water and effective sanitation are directly related. In Rural or poorer areas, sub-standard sanitation will directly influence the water quality at lower areas due to the forces of gravity. Ultimately, water and sewage will flow into the valleys of the area, and create pools. This standing water/sewage will start to infiltrate through the soil and eventually join fresh underground water. The Vetiver can absorb many nutrients and heavy metals from the sewage, which could otherwise be hazardous to fresh water, man and ultimately, the environment.
Industrial Effluent Treatment
Phytoremediation for industrial waste water polluted with heavy metals could be carried out using vetiver technology. The quality of wastewater, and especially the concentration of heavy metals, had a significant effect on vetiver growth and the uptake of heavy metals. In practice, vetiver could be grown in a hydroponic system using a floating platform, such as a bamboo or PVC pipe raft, to achieve heavy metal uptake to the shoot and root. This system enables the shoot and root to be easily harvested. The vetiver shoot may be used for Bio-fuels or handicraft products, while the root part could be a source of essential oils. High concentrations of heavy metals could also affect plant growth and cause low removal efficiency, therefore, this method would be suitable after pre-treatment or in low-medium heavy metal polluted wastewaters. The number of vetiver plants used for the clean-up of wastewater should be of a sufficient quantity to reduce the concentrations of heavy metals to the industrial effluent standards, otherwise, re-cultivation may be necessary to achieve the good results.
Remediation of Eutrophic Water (Algal Bloom Control):
Algal growth in rivers and dams are major concerns around the world, as soluble N and particularly P are usually considered to be key elements for water eutrophication, which normally leads to blue green algal growth in inland waterways and lakes. The removal of these elements by vegetation is a most cost effective and environmental friendly method of controlling algal growth.
Research in China indicated that vetiver could remove dissolved nutrients and reduced algal growth within two days under experimental conditions. Therefore, Vetiver System can be used very effectively to control algal growth in water infested with blue-green algae. This can be achieved by planting vetiver on the edges of the streams or in the shallow parts of lakes where usually high concentrations of soluble N and P occurred.
(Eutrophication is a naturally occurring process in which water bodies become enriched with inorganic plant nutrients, often the result of anthropogenic pollution with nutrients, particularly the release of sewage effluent and agricultural run-off carrying fertilizers into natural waters).
Pollution Control Using Constructed Wetland System
Being a wetland plant, vetiver can be used in a constructed wetland system. It has been demonstrated that vetiver can treat almost raw domestic effluent without having to be diluted. Perhaps its greatest large-scale application is in wetlands. Vetiver is eminently suitable for use as a vegetative buffer or wetland plant species due to its morphological and physiological features.
Natural and constructed wetlands have been shown to be effective in reducing the amounts of contaminants in runoff from both agricultural and industrial lands. Vetiver grass is highly tolerant to farm chemicals so VS is very effective in trapping nutrients and agro-chemicals in runoff water, preventing these pollutants reaching rivers and streams.
The key in controlling off-site pollution by nutrients and agrochemicals is to control sediment movement. If the sediment could be effectively trapped at source, the degree of downstream pollution would be greatly reduced. Vetiver hedges have been shown to be a very effective and low cost means of retention and decontamination of particle-bound agro-chemicals, especially pesticides and nutrients in runoff water from agricultural lands.