Conference on Vetiver Bio-Engineering Technology for Erosion and Sediment Control and Civil Construction Stabilisation

19 - 21 October 1999, Nanchang of China

I. Soil erosion and new construction in China:


Soil erosion has been a problem ever since man started to cultivate land. It became more critical with increasing population. In the recent decades, forestry area decreased dramatically in China. For example, the forest coverage declined from 30-40% in 1949 to about 10% at present in the area of upper reaches of the Yangtze River. The soil erosion area increased from 363,800 sq. km in 1957 to 569,700 sq. km in 1990'S. This represents an increase by 56.6% in the 30 years. The sediments passed through the Three Gorges each year in 1990'S reached up to 720 million tons. Based on investigation the level of the river bed of main reaches of the Yangtze River raises 1 meter in every 10 years. As a result, during the flooding season the water level became much higher than that of the surrounding land surface. For the lakes as Dongtinghu Lake, the water level during flooding season was also higher than the land surface, usually 10 m higher, which threatened people's life seriously and led to disastrous consequence.

In 1998, based on the statistics by the authority the heavy flooding caused 4,150 death and direct economic lose of 255, 090 million Yuan RMB (about US$31, 108 million) in this country. There were 6.85 million houses were destroyed. And 18.393 million people had to immigrate to safety places.

In addition to many new farm land reclaimed for food production on the more steep slopes, in the recent years following national economy reform, farmers and government officers have increasing interests in clearing forests for commercial tree (economic forests) production, and called it as `forestry revolution'. They cleared vegetation, built earth terrace and planted tea, mulberry tree, longan, and chestnut, etc. in a large scale. Because this kind of new farming development lacked of protection measures, it usually led to more soil erosion, resulting in the decline of soil fertility. Consequently, the commercial trees can not grow well. And more often, the soil was usually eroded off before commercial trees and new vegetation grew up.

In developing countries, in addition to farming, non-agricultural practice resulted in a rapid increasing soil erosion as well. These developments includes the constructions of highway, railway, dam, mining, quarrying, and buildings, etc. Studies in the United States some years ago showed that construction constituted some 20 times the rate of other forms of erosion attributable to land use on average (Goldmann, al, 1986). Unfortunately, this serious erosion problem is not fully understood by policy makers and scientists in developing countries. In China for example, since the national economic reform the construction of highway forms the major component of economic development and was deemed as an important channel for poverty alleviation. The total length of highway increased from 1,118,000 km in 1994 to 1,186,000 km in 1996. The annual increase reached 34,000 km. However, caused by financial limitation many highway embankments were not properly protected and caused serious new erosions. This has not only led to the destabilisation of the highway foundation but also to the pollution of the surrounding environment.

Since national reform in many places quarrying and small minings became an important industry for farmers, and often the only channel for generating profit. These practices often lead to further erosion problems.

New farming develpment and new constructions often results in accelerated run-off, new soil erosion, increasing sediments and land collapse in a considerable area outside the development sites. Unstable new embankments formed serious point sources of erosion, that created major problems further down in the catchment area. Many farm lands with crops at the lower area were buried by sediments each year. In the mountainous area, some unprotected constructions led to high risk and disaster when it was built along river bank in the deep canyon area. The landslide blocked the river and caused the change of flow direction and threatened people's life.

II. Vetiver for erosion and sediment control and civil construction stabilisation:

objectives of the conference

A) Vetiver grass technology research and development in China and overseas

As a natural gift, the vetiver is a miricle plant for erosion control. Vetiver grass when planted as a narrow hedge across the slope of the land will stop soil erosion, reduce rainfall runoff, safeguard infrastructure against degradation, sequester heavy metals and CO2, promote revegetation of native species on denuded land, provide missing organic matter in tropical low fertility soils to mention a few uses. Many conservation technologies take years to be effective. Vetiver on the other hand begins to impact the environment within the first year and even within the first few monthes and from then on. Once established it cannot be burnt out, it does not spread, i.e. it stays where you put it, it cannot be flooded out (remains viable even after 12 months underwater). Based on these and many other characteristics, the technology was recently recognized by a panel of international judges to be the best of 71 sustainable technologies that were entered for the "John Franz Sustainability Award".

As early as in 1988, the president of The Vetiver Network (TVN, international) Mr Dick Grimshaw from UK introduced vetiver to China for soil erosion control through Red Soil Project funded by the World Bank. In 1996, CVN was established under financial support by TVN. To introduce vetiver to China more rapidly, a workshop was organzed by CVN with participants from limited provinces in southern China in 1997. Since then, the grass, has been experimented and field tested in many places fron Hainan Island in the south to Hebei Province in the north, including the provinces as Anhui, Fujian, Guizhou, Guangdong, Guangxi, Gansu Hunan, Hubei, Jiangxi, Jiangsu, Sichuan, Yunnan, and Zhejiang Provinces. The followings are some examples:

- Experiments were carried out by research institutes and universities on the biological characteristics; hedge establishment and maintenance on newly built terraces and slopes; hedgerow impacts on soil fertility, moisture, crop yield, and soil losses (these experiments and field trials confirmed the effectiveness of the technology);

- In Fujian and Guangdong Province, large scale demonstrations were implemented and have shown the effectiveness of vetiver for barren land (Red Desert) rehabilitation, river bed stabilization, and embankment stabilization for railroads and highways;

- Repruduction bases were established in several provinces in southern China;

- Vetiver hedgerows were established to protect tea, tea oil (camellia), and citrus plantations;

- Vetiver grass has been used to feed fish, livestock, to mulch ground surface of orchards, and to cultivate edible fungus.

Because vetiver grass has many advantages that other plants do not have, it is welcomed by not only agricultural scientists but also engineers:

-- Vetiver has a strong fibrous root system that penetrates and binds the earth to a depth of over 3 m and can withstand the effects of tunneling and cracking. The grass is more effective (than hard wood roots) in the mechanism of root reinforcement on soil slopes, and can stabilize the loosing materials of disturbed soils and prevent the remove of slope surface soil layer, as clearly demonstrated on extremely unstable and massive highway embankments and cuts in Malaysia (Diti Hengchaovanich and Nimal S. Nilaweera Erocon, 1996).

-- Compared with other short grasses vetiver can more quickly form a dense, permanent hedge, and need very little management, as pointed out by engineers at National Super Way Conference held in November 1998 in Kunming.

-- It is much cheaper using vetiver grass than using rocks for embankment protection. For example, in Fujian Province, it costs 30 Yuan/sq.m using rock to protect embankment, while only 3 Yuan using vetiver.

-- Vetiver was tolerant to hot, dry or waterloging, low-fertility, a wide range of pH and heavy metals, that is much suitable for erosion and sediment control and civil construction protection.

-- Vetiver can not only protect soil from water erosion but also from serious wind erosion as demonstrated in sandy dunes along the coast of Fujian Province, therefore it can appropriately fix embankment consisting of loose sand that is a common material in some Provinces in coastal area of south China.

-- Vetiver can not only stabilize embankments but also greening them up while the traditional rock protected embankment usually needs to clear the vegetation and cause environmental problem.

Because the grass has above advantages, in the very recent years, engineers from civil constructions, highway constructions in particular, expressed high enthusiasm in testing and using the grass.

-- In addition to many national journals on agriculture, soil scoience, forestry, ecology, and environment, vetiver technology was introduced by several regional and provincial highway publications in 1998, such as:

( East China Highway Journal,

( Guangdong Highway Journal,

( Newsletter of Highway Society of Jiangsu Province,

( Science and Technology of Communications of Zhejiang Province.

( Proceeding of National Super way Conference, Kunming, November 1998

( Highway Survey and Design of Fujian Province.

-- Vetiver technology formed one of the most important topics in the East China Highway Conference held in Xiamen of Fujian Province on 8-11 June 1998, and China's National Super-Way Conference held in Kunming of Yunan Province on 26-29 November 1998.

-- In August 1998, the Highway Bureau of Fujian Province released an official document to each city and county and asked them to learn and use vetiver technology to protect highway embankment.

B) Conference Objectives

The vetiver conference was proposed based on the following facts:

-- there have been great progresses in testing and using the grass in the past two years, but most of their practice was distributed in different places and was independent and even isolated;

-- more and more people wish to know the experiences obtained by others from different regions or different disciplines, both domestic and abroad, before they test and use the grass;

-- many people wish to have a look at existing demonstration before they start to work with vetiver.

The main objectives are to:

1) Introduce most up to date successful experiences obtained by both international experts and Chinese scientists in vetiver bio-engineering techniques.

-- exchange ideas and experiences in vetiver application for erosion and sediment control and civil construction stabilisation;

-- raise awareness of the serious consequence of soil erosion from both new farming development practice and civil constructions;

-- disseminate vetiver technology to multiple institutions with different disciplines;

-- discuss strategy and methods of vetiver technology extension for erosion and sediment control and civil construction stabilisation;

-- introduce and generate methods to accelerate vetiver planting material production in order to meet the needs of rapid development of agricultural practice and civil constructions.

2) Establish linkage and cooperation between scientists from China and from foreign countries and between institutions with different disciplines, agriculture, forestry, environment, engineering, etc.

III. Jiji grass, a `cold vetiver' for cold region

another objective of the conference

As early as in 1994, Mr Dick Grimshaw from UK investigated soil erosion in Loess Plateau and prepared to launch the soil conservation project, which covered over 2 dozens of counties in 4 Provinces funded by the World Bank and found that jiji cao (or jiji sao), a pronunciation in Chinese (Achnatherum splendens) had special function in soil erosion control in north China, in particular in the Loess Plateau area where soil erosion has been proved to be very serious. Very recently, several field surveys were implemented in north China which confirmed that the grass was similar to vetiver but tolerant extremely draught and cold:

-- Its natural habitat is the saline soils in northwest China such as Inner Mongolia, Ningxia, Xinjiang Provinces. When planted on upland soils (such as the Loess soils) it grows extremely well.

-- Like vetiver it also belongs to Gramineae. Farmers in Shanxi and other provinces used it for stabilizing the vertical cuts made in the hill slopes behind their houses to prevent slippage and damage to the houses, and for home garden protection.

-- The grass has strong, deep (at least 3 meters), and profuse roots.

-- It is completely drought proof, and withstands extreme cold.

-- It has good longevity and is usually propagated vegetatively by plant division and is not invasive under cultivation condition.

-- The grass was used also for feeding animals with young leaves, for making basket, broom, mattress, rope, curtain, shed roof cover, and medicine . And also, it was used for pulp purpose and for highway protection.

The jiji grass appears to have many similarities to vetiver grass, although there are some distinct differences, including a less dense and weaker leaf system. However there are enough similarities, as well as farmer experience and knowledge, to suggest that jiji grass could be key to long term embankment protection (terrace, dams, and roads) in north China if planted as a closely spaced in line hedgerows across the slope of embankment as has been widely proven for vetiver. It also may well be possible to use it as an effective contour hedgerow on unterraced sloping land. In Dongsheng of Inner Mongolia dozens of kilometers of highway embankment was protected with the grass.

The CVN's newsletters will introduce the jiji grass. Experiments and demonstrations on the grass are being implemented in Ningxia and Shanxi Provinces. The grass was also experimentally introduced to south China. The proposed conference will introduce jiji grass as `Cold Vetiver' to participants and potential users in north China and foreign countries and will discuss further cooperation between China and foreign countries on the tests and studies on jiji grass.

IV. Program

A) Program

The proposed conference will include:

1) Pre-conference investigation on jiji grass in Shanxi Province of North China, 14 - 18 October 1999 (if funding permitted)

2) Conference in Nanchang (19 - 21 October):

-- key presentations by recognized experts from China and other countries,

-- oral presentations,

-- group discussion,

-- poser presentations,

-- visiting demonstrations of vetiver for the protection of farm land, highway embankment and other earth works,

-- exhibitions of various papers, photos, and publications, and video/computer medium.

3) Post-conference survey to Wuyi Mountains (22 - 24)

-- visiting large demonstrations and contracted erosion control projects in Fujian Province and Possibly Jiangxi Province as well.

B) Sponsorship

Limited foreign experts will be invited to attend the conference supported by Chinese Academy of Sciences, National Natural Science Foundation of China, and possibly other dornors based on their contributions.

C ) Location

The conference will be held in Nanchang of Jiangxi Province where the local authority has high enthusiasm in using vetiver.

D ) Time

The conference will be held on 19 - 21 October 1999.

Optional pre-conference investigation on jiji grass will be held on 14 - 18 October.

Post-conference survey will be organized on 22 - 24.

E ) Working language

Working language will be English and Chinese, translation will be provided.

F ) Expected output

The expected output will include:

1) Vetiver Newsletters disseminating the conference information and introducing vetiver technology for erosion and sediment control and civil construction stabilisation at home and abroad will be produced and delivered to government officials, scientists, and potential participants and vetiver users both before and after the conference.

2) Vetiver FACT sheets which vividly describing the use of the grass will be produced and sent to the new and old users at county and prefecture level.

3) Conference Proceedings will be published in English and to be disseminated worldwide through The Vetiver Network, and CVN after the conference, if funding permits.

4) A linkage among scientists, engineers and government officials involving in numerous disciplines between China and other countries will be established through the conference to strengthen the further cooperation.

G ) Organization

The conference will be organized by CVN, in corporation with multiple national and provincial institutions, including National Natural Science Foundation of China, Chinese Academy of Sciences, etc.

V. Costs

Registration: US$ 150 for the conference 19 - 21 Oct. 1999,

US$ 300 for post-conference survey 22 - 24 Oct. 1999,

US$ 400 for pre-conference investigation 14 - 18 Oct.1999

Accommodation (hotels and meals): US$ 50/day

All payments are required in cash in US Dollars paid at the time of arrival.

VI. Climate

As usual, Nanchang is warm in October with mean monthly temperature around 25C.

VII. Insurance

The organizers will not be held responsible in case of accidents, illness, theft or death while traveling to and from, or staying in China to attend the workshop and the field surveys.

VIII. Contacts:

Liyu Xu

Coordinator of China Vetiver Network

c/o Institute of Soil Science

P.O.Box 821

Nanjing 210008, China, P.R.

Fax: 86-25-3353590

Tel. 86-25-3367364

Email: [email protected]


Request for Registration

Vetiver Conference, 19 - 21 October 1999 Nanchang, China, P.R.

--------------------------------------------------------------------------------------------------------Full Name: Title:


Nationality: Institution:

Mailing address:

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O I will attend the conference 19 - 21 October 1999

O I will participate in the pre-conference investigation 14 - 18 October 1999

O I will participate in the post-conference survey 22 - 24 October 1999

O I will submit a paper titled:

Send this form by 1st September 1997 to: Liyu Xu, Coordinator of China

Vetiver Network, c/o Institute of Soil Science, P.O.Box 821, 71# Beijing Donglu, Nanjing 210008,

China, P.R., Fax: 86-25-3353590, Tel. 86-25-3367364,

Email: [email protected]