Natural resources and land use in Viet Nam

                   Thái Công Tụng

Viet Nam has a land area of 331 041 km2, stretching from north to south over  1 600km, along the eastern coast of the Indochinese peninsula (from 8o30'N to 23o25' N) and land borders of 1150km with China, 1650km with Laos and 950km with Cambodia.  Three quarters of the country consists of  mountains, hills and plateaus, but the topography is in  general relatively low: one tenth only of the territory is situated at above 1 000m. Fansipan on the Hoang Lien Mountains  is the highest point at 3 142m. That topography is however  very rugged with deep valleys.

The country is S-shaped, with a long coastline of more than 3 000km and broad deltas of the Red River in the North and the Mekong delta in the south, linked by narrow plains of Central coastal plains. A broad, shallow continental shelf follows the shape of the land, wide in the north and south and narrow in the middle. The sea bed is muddy in the two delta areas and sandy along the central coastline.

From north to south, a long chain of mountains, called the Trường Sơn range, runs almost the full length of the country, from the northwest border to the southeastern region. Spurs of this range stretch eastward to the Oriental Sea, segmenting the central coastal region into different plains. Offshore islands are: Phú Quốc and Thổ Chu Islands in the Gulf of Thailand, the Côn Đảo Islands in the Oriental sea, the Paracel Islands east of Đà Nẳng and Spratley Islands south-east of Nha Trang. The Paracel Islands were seized by China in 1974 by force and the Spratley islands are claimed by various countries in the vicinity.

1.Main ecosystems of Viet Nam .

Based upon various factors such as climate, soils conditions, geomorphology,

here are 7 ecosystems prevailing in Viet Nam: Northern Mountains and midlands, Red

River delta, North Central Coast, South Central Coast, Central Highlands,South-East,

and  Mekong River delta.

1.1 The Northern Mountains and midlands:

This ecosystem  covers sixteen  provinces: Hà Giang, Cao Bằng, Lào Cai, Bắc Cạn, Lạng Sơn, Tuyên Quang,Yên Bái, Thái Nguyên, Phú Thọ, Vĩnh Phúc, Bắc Giang, Bắc Ninh, Quảng Ninh in the North East and Lai Châu, Sơn La, Hoà Bình in the North West. With 102 949km2 in acreage, it is quite diverse in terms of altitude, geological formations and vegetation. Sparsely populated, it is inhabited primarily by more than 20 ethnic groups such as the Nùng, Thái, Dao, H'Mong which are distinguished by their own language and culture.

1.2 The  Red  River  delta is crisscrossed by many rivers, out of which the Red River and Thái Bình  rivers are the largest. The delta, a main rice-growing area, covers  cities and provinces such as Hà Nội, Hải Phòng, Hà Tây, Hải Dương, Hưng Yên, Hà Nam, Nam Định, Thái Bình and Ninh Bình and has 12 457 km2 in acreage .

1.3 The North Central Coast ecosystem covers six  provinces situated north of the Hải Vân pass: Thanh Hoá, Nghệ An, Hà Tỉnh, Quảng Bình, Quảng Trị, Thừa Thiên. Total land area is 51 187 km2 .

1.4 The South Central Coast ecosystem covers seven  provinces south of the Hải Vân pass: Quảng Nam, Quảng Ngãi, Bình Định, Phú Yên, Khánh Hoà, Ninh Thuận, Bình Thuận and one city, Đà Nẳng. Total land area is 45 823 km2.   

Along the North Central and South Central Coast, a long mountain range, called Trường Sơn, divides the watershed of the Mekong river from the drainage basin of the Oriental sea. That range is steep in the north and central part and gradually ending in undulating plateau in the south.  From this mountain range to the Oriental sea, five following geomorphological landscapes are recognized: the mountainous areas, the hilly areas, the old terraces, the alluvial plains and the sandy dunes.

1.5 The Central Highlands are plateaus of altitude ranging from 400m to 1200m and its population is formed mostly by ethnic minorities (Rhade, Giarai, Mnong, Stieng..). This ecosystem covers five provinces, namely Kontum, Pleiku, Darlac, Dak Nong and Lâm Đồng. Total area is 55 569 km2.

1.6 The Southeast region. It is a transition zone between the highlands and the Mekong delta. This ecosystem covers five provinces such as Tây Ninh, Bình Dương, Bình Phước, Đồng Nai, Bà Rịa-Vũng Tàu and a big city, Ho Chi Minh city, formerly Saigon. Total area is 23 481km2. This region is economically diversified and has the highest income in the country.

1.7 The Mekong River delta covers a land area of  39 575 km2 (nearly 4 million ha) with following provinces: Tiền Giang, Long An, Bến Tre, Đồng Tháp, An Giang, Kiên Giang, Cần Thơ, Trà Vinh, Vĩnh Long, Sóc Trăng, Bạc Liêu, Ca Mau and supports over 16 million people. 30% of that total acreage are alluvial soils, which are distributed along Tiền and Hậu rivers and between these two rivers. The rest is acid sulphate soils in the depressions and saline soils along coastal areas. These two kinds of soils are also cultivated, although not as intensively as alluvial soils. This ecosystem contributes 22.5% of total GNP, mostly from agriculture, animal husbandry and fisheries. Agricultural lands are increasing, thanks to water management in some areas which had soil problems, thus helping rice production.

2.Water resources.

            Viet Nam is rich in water resources, being endowed with a network of great rivers and vast alluvial basins to hold groundwater. Conditions, however, vary widely from region to region.

2.1. In northern Viet Nam, two river systems, namely the Red River and the Thái Bình river are distinguished.

The Red River system is the largest river system in northern Viet Nam. This system comprises various affluents such as the Đà, the Chảy, the Lô ..rivers, covering a total catchment area of 143 700 km2. Of these 3 rivers, the Sông Đà has the largest water flow, contributing with some 43% to the total water flow of the Red River system. The Sông Đà has its origin in southern China, were approximately 50% of the whole basin is located. The river has a total length of 980 km of which 480 km runs through Vietnamese territory until it joins the Red River, thus  located in 5 provinces: Lai Châu, Sơn La, Lao Cai, Yên Bái and Hoà Bình.

Sông Đà is also the river which carries most of the sediment loads. On the Sông Đà is the Hoà Bình dam, located 2 km upstreams from Hoà Bình town. That dam is one of the most significant resource projects in Viet Nam and the largest hydro-electric project in Southeast Asia, constituting the country's principal source of electricity, with a maximum generating power capacity of 1,920 MW. Besides that, the dam contributes to flood control (the Sông Đà is the main tributary of the Red River) and has enabled supplementary irrigation of some 30,000 ha in the Red River delta downstreams. Due to deforestation upstreams, that large reservoir has a high siltation which reduces its life span.

The Thái Bình river system  consists of the Thương, Lục Nam and  Cầu rivers which met in Phả Lại.

Most water resources in the  delta come from the Red River and the Thái Bình river systems, with an annual flow of 137 000 million m3 from which 90 000million m3 are generated in the territory of Viet Nam, since more than half of the Red River basin lies outside the country. Due to frequent floods in the past, a long system of dykes was built successively since the 12th,  century to protect the delta. The two existing Hoà Bình and Thác Bà reservoirs help flood mitigation.

2.2 .The Mekong river, when flowing into the Viet Nam territory, divides itself into 2 tributaries: the Tiền (Upper river) and Hậu (Lower river) rivers.

The Tiền river crosses such localities as Tân Châu (Châu Đốc), Hồng Ngự, Cao Lãnh whereas the Hậu river flows through Long Xuyên, Cần Thơ, Trà Ôn (Trà Vinh). Besides those two main rivers, the delta is crisscrossed by many canals which help irrigation and drainage.

More than 90% of the Mekong basin lies outside of Viet Nam and 90% of its flow is generated outside the country . The availability of water resources in the Mekong Delta alternates from surplus to shortage every six months, affected by a tropical monsoon climate. From June to October, heavy rainfall occur, causing  long periods of flood but at the end of the dry season, in April, the water level of rivers is lowest, causing saline intrusion through estuaries. Also, the water availability is increasingly beyond Viet Nam's control, since upstream countries are withdrawing increasing amounts through reservoirs and irrigation schemes, causing less water discharge and thus inducing salt intrusion in the delta itself during the dry season. Besides recurrent flood, tides are another important aspect in understanding the hydrology of the delta where the South East Sea and Gulf of Thailand influence the tidal action. On the East sea coast, tides are semi-diurnal with an average amplitude of 3.5-4.5m whereas on the Gulf of Thailand coast in Rạch Giá area, the tide is diurnal with a lower amplitude of 0.5-0.8m. Tides influence many estuarine processes such as the extent of saline intrusion and the influx of sand into river channels.

2.3 All rivers in Central Viet Nam are typically short, since the coastal plains consist  only by long and narrow strips dominated by a long chain of bare mountains called Trường Sơn. Watersheds are generally small, except the watersheds of Sông Mã in Thanh Hoá and Sông Ba in Tuy Hoà. They are also subject to frequent flooding, especially with the heavy cyclones occurring around October-November.

2.4 In the Central Highlands, there are three main river systems which flow respectively to the Mekong river in the West, to the Oriental sea in the East and to the South.

.to the West : the Se San River system is located in the northern part of Kontum and Gia Lai (Pleiku) province. As a main tributary of Mekong River, Se San springs from Mount Ngoc Linh which is 2 598 m high and flows southwest in the mountainous and plateau area of western Trường Sơn at 800-1000m above the sea level. The river comprises two tributary rivers: the Dak Poco,  and the Dak Bla. A storage dam was built recently in that area, the Yali dam, to produce 700 MW of hydroelectricity.

The Srepok river system has its source in Darlac plateau. Both rivers (Sesan, Srepok) flow to StungTreng in Cambodia .

 .to the East: the sông Ba also springs from the Kontum mountains, but flows southwards to An Khê, Cheo Reo and from this locality, it goes eastwards to Tuy Hoà, in the Oriental sea.

 .to the South: the Đồng Nai river is originated from the Dalat plateau and flows southwards to the southeastern region with some of the following tributary rivers: the  Bé,  La Ngà and Saigon rivers. Some big storage dams (La Nga, Da Nhim, Dau Tieng) are built on those rivers for the production of hydroelectricity or for the irrigation.

Besides rivers and streams, water is also available in man-made reservoirs. Water resources are essential for agriculture, for livelihoods as well as for industry . They are essential for irrigated agriculture to sustain Viet Nam's economic growth and address rural poverty . 

3. Soils resources

Soils vary widely in their characteristics and properties. In order to establish the relationship between their characteristics, they need to be classified. Let us review major soil orders in Viet Nam (cf Soil map of Viet Nam 1996) .

3.1 Arenosols

            Arenosols are soils developed from unconsolidated materials, usually sands, that have little profile development. Because of the sandy texture, arenosols have a low moisture content. With their low clay content, the ability to retain added nutrients is low.  Arenosols include beach and sand dune deposits and are present mostly in the sandy ridges of the coastal areas of Central Viet Nam. They are either of red color (Rhodic Arenosols) such as sand dunes in Phan Thiết province or of yellowish colour (Luvic Arenosols) elsewhere in other coastal areas. Sandy ridges along the East sea in the Mekong delta, such as in Trà Vinh, Gò  Công are also Arenosols. Total acreage of Arenosols 533 434 ha

3.2 Fluvisols

Fluvisols are alluvial soils which are young soils developed on riverine, lacustrine and fluvio-marine deposits. Total acreage of Fluvisols is 3 400 059 ha, which is10.27% of the whole acreage of the country. They are young water-borne sediments without prominent horizons except at the surface and their location is in the active flood-plains, meander plains, levees, cover flood-plains, backswamps or infilled channels of the rivers.

Alluvial soils along the Red River carry each year many sediments especially during the rainy season, but since the construction of a big dam on Sông Đà river near Hoà Bình, the volume of sediments decreases considerably. Alluvial soils of Mekong river  are less flood-prone than those of Red River delta. They are fertile soils and the bulk of food production relies heavily on these soils.

The most significant property associated with Fluvisols is that the land on which they occur is flat, helping easy irrigation for rice as well as vegetables. A second property is a high water table. The main features of the alluvial soils are derived from the deposition laid by the numerous tributaries of the Mekong, the Red River and the small rivers in  Central Viet Nam. These streams, draining the mountains, bring with them the weathering products of rocks constituting the mountains, in various degrees of fitness and deposit them as they traverse the plains. In some coastal areas, especially where tides are not pronounced, the accruing land in deltas is rapidly secured, desalinized and used to grow crops. 

This is by far the largest  and most important soil group of Viet Nam, contributing the largest share to its food production. Fluvisols have for many centuries supported high population densities.

3.3 Salic Fluvisols

Total acreage of those saline soils is 971 356 ha. Saline soils occur in estuarine coastal areas. Saline soils occupy a coastal fringe, from the North (Quảng Ninh, Thái Bình) to the South (Cà Mau). Near the sea, they are under mangrove forests and salinity decreases inwards. Current salinity intrusion into the Mekong delta can be as far as 100 km from the coast in Cà Mau area; in other coastal provinces, salinity intrusion extends inwards 50 km or more. The reason is during the dry season, low discharge in the mainstream rivers, plus overpumping for irrigation in upstream areas make salt intrusion coming up from the estuaries easier. 

3.4 Thionic Fluvisols

Total acreage of Thionic Fluvisols is 1 863 128 ha. Commonly called Acid sulphate soils (đất phèn), they have thick surface horizons with high humus content and occupy large areas in the Mekong River delta. Sediments containing sulphides, mostly iron sulphides or pyrites, have been formed throughout geologic time. The cause of the acidification is the oxidation of pyrites, FeS2, with the formation of sulphuric acid. Sulphates in seawater are reduced by bacteria under anaerobic conditions to form hydrogen sulphide,  H2S. The hydrogen sulphide reacts with iron compounds in the soil to form ferrous iron sulphide, FeS2. As long as the sulphides in the sediments remain below the water table, they are innocuous. With the onset of rains, the pH of acid sulphate soils decrease sharply.  When exposed to air, such as in periods of prolonged drought, after draining for agricultural or urban development, they oxidize. Oxidation involves the conversion of sulphide minerals in the soil, chiefly pyrite, to ferric sulphate (jarosite) which produces the yellow mottling and sulphuric acid. Further reaction of this acid with clay minerals in the sediments forms aluminium sulphate, which may cause aluminium toxicity .

Acid sulphate soils occupy a big stretch in the Đồng Tháp Mười and the Long Xuyên quadrangle in the Mekong delta. Acid sulphate soils, with their strong acidity are  problem soils, since they limit the scope of cultivation.

3.5 Gleysols.

Gleysols are soils in depressions and can be acid (Dystric Gleysols ) or with a black layer of humus (Umbric Gleysols). Total acreage of Gleysols is 452 418 ha. Gleysols are poorly drained and are found mostly in the plains of Red River delta where generally rice can be grown only in the dry season. Gleysols are scattered in the Southeastern region, north of Saigon in small depressions.

3.6 Histosols

Histosols are organic soils dominantly composed of organic matter and are commonly known as peat or muck. They are found mostly in U Minh area, in the Mekong delta. Total acreage of Histosols is 24 941 ha .

3.7 Andosols

Andosols are soils derived from volcanic ash, containing a high proportion of vitric material. They are black or brownish colour, generally found near former old  volcanoes in the Southeastern region (Định Quán, Đồng Nai).The natural soil fertility is high and is renewed by weathering of minerals. They have a high available water  capacity and are generally freely drained .Total acreage is 171 402 ha, occupying 0.5% of the acreage of the country .

3.8 Luvisols

Luvisols are well drained soils and are neither very highly weathered nor very strongly leached. Having an argillic B horizon with base saturation > 50 percent .They are derived from a wide range of parent materials, including  limestone or sandstones. From limestone, they are mostly found in the upper mountainous regions in Cao Bằng, Sơn La, Lai Châu . Luvisols developed from sandstones are more acid than from limestone . Total area of Luvisols is 112 939 ha .

3.9 Lixisols

They are reddish brown soils in semi arid climate, where evapotranspiration is higher than rainfall like in Phan Rang and Phan Thiết provinces. These soils have high cation exchange capacity and quite fertile if they can be irrigated. Total acreage of Lixisols is 42 330 ha

3.10 Calcisols.

Only a small acreage of 5 527 ha of Calcisols is identified in the soil map of Viet Nam. Calcisols are formed in dolines e.g. small valleys surrounded by limestone mountains. They are rich in calcium and magnesium. Limestone concretions are omnipresent in the soil profile of Calcisols.

3.11 Acrisols

Acrisols have an argillic B horizon with base saturation less than 50 percent. They are insufficiently weathered to be Ferralsols but more strongly leached than Luvisols.  Acrisols with nearly 20 million ha are found everywhere, on a wide range of geomorphologic conditions :

. in the high mountains, they are more or less freely drained with a high organic matter content (Humic Acrisols)

. in the poorly drained areas, they have gley horizon (Gleyic Acrisols). They are found in Midland regions of North Viet Nam as well as South Eastern Region, north of Saigon.  Total acreage is 101 471 ha

. in sloping conditions, they have a reddish colour (Ferrallic Acrisols). These Ferrallitic Acrisols can be weathered from basaltic rocks (Darlac and Lâm Đồng provinces) or from metamorphic rocks in different geomorphologic conditions (mountains, sloping lands). Ferrallic Acrisols are deeply weathered and have clayey and stoneless textures. Textural profiles may be uniform or gradational . Colours may be red, dark red, reddish yellow. They are strongly acid (pH< 5.5), have low cation exchange capacity ( < 20 m.e./100 g of clay) and have low base saturation values (usually< 20 percent). Kaolinite is the dominant clay mineral.

. Gently sloping to flat soils of Haplic Acrisols are found mainly on old transported materials  in the old alluvial terraces north of Saigon and  in the midland regions of North Viet Nam, Plinthic Acrisols  are quite common. Relief conditions are generally flat or gently sloping .Soil fertility is quite poor.

3.12 Ferralsols

            Ferralsols occupy nearly 10% of total land area. They are all in situ formations from the underlying basaltic rock or limestone. They are strongly weathered, mainly reddish and are developed on stable landscapes that have been either not or only slightly influenced by erosion.

Ferralsols developed from basalts are red soils  in the Central Highlands (Lâm Đồng, Pleiku, Banmethuot), in the Southeastern region (Bình Phước, Gia Kiệm, Xuân Lộc areas) as well as in localized areas of Quảng Trị (Gio Linh, Vĩnh Linh), Nghệ An (Phủ Quỳ). Ferralsols can also be weathered from limestone like in Cao Bằng, Lạng Sơn.

On the soil map of 1/1 000 000, 3 units are distinguished:

.Reddish brown latosols (Rhodic Ferralsols) which can be found in the basaltic plateaus of Central Highlands, Southeastern region or in some localized areas of Quảng Trị and Nghệ An. They are deeply weathered and are acid to mildly acid soils. They have also excellent physical properties and efficient surface drainage. Coffee, tea, pepper are grown on these red soils.

.Yellowish brown soils (Xanthic Ferralsols) which are developed on basic parent materials like limestone, basalt or andesite. They are less clayey than reddish brown latosols, well drained and acid. They are found in a wide range of landforms: flat, sloping terrain and are present in the upper midlands of North Viet Nam (Cao Bằng, Lạng Sơn) or in the basaltic areas of the Southeastern region.

. Humic red and yellow soils on mountains (Humic Ferralsols ) which are found in high altitude areas (from 800m upwards) and sloping conditions.

In the soil group of Acrisols and Ferralsols, laterite is a quite common feature. It is a compact or vesicular rock composed essentially of a mixture of the hydrated oxides of aluminium and iron with small amounts of manganese oxides.

3.13 Alisols

Generally, they are localized in high mountains such as in Fan Si Pan (northern mountains), Chu Yang Sin (Central Highlands) above 2 000 m where average temperature is less than 15⁰ C and where vegetation is mostly Azalea, Rhododendron and coniferous trees. Total acreage is estimated at 280 714 ha.

3.14 Leptosols.

They are shallow and eroded soils and soil fertility is very poor, due to the presence of rocks near the soil surface. Total  acreage is  495 727 ha.

3.15 Nitisols.

They are brown or reddish-brown soils which, though deeply weathered, are moderately fertile. With a total acreage of nearly 100 000 ha, they are interspersed within the ferralsols in the Ban Me Thuot  area (Central Highlands).Soil fertility is generally high and they have good potential for growing fruit trees or perennial trees .

4. Forestry resources.

The original vegetation in the mountains of Viet Nam is a very complex one, resulting from the influences of three different geographical  areas: Yunnan - Himalaya, Northern Viet Nam - Southern China and India- Malaysia. The highly diversified climate, (warm temperate, dry hot climate, wet tropical..), soils (dry calcareous soils, wet saline soils, fragile sandy coastal ridges..) and altitudes of Viet Nam  help produce the conditions for its highly diversified forest ecosystems: natural forests, evergreen broad-leaf and semi-deciduous forests, deciduous forests, conifer forests, mangrove forests, bamboo forests etc . Forests provide to the rural and urban population fuelwood, timber as well as some non-timber products such as honey, rattan, bamboo shoots, edible fruit, mushrooms, medicinal plants ..

Regarding only flora, it is estimated that Viet Nam has about 12 000 species of higher plants (Pham Hoang Ho) but only 7 000 have been identified. Viet Nam was rated as the 16th most biologically diverse country in the world. Endemism is high in many groups. An estimated 33% of the flora is considered endemic..

4.1       In the Northern  Mountains and midland ecosystem :

. the low altitude mountains in Sơn La and Hoà Bình have broad-leaved evergreen forest with  major species such as: Vatica fleuryana, Parashorea stellata, Toona febrifuga ,Sapindus mukorossi, Pelthophorum tonkinensis, Cassia sp., Spondias mangifera, Gmelina arborea, Dipterocarpus tonkinensis, Terminalia myriocarp  and trees belonging to the Dipterocarpaceae, Fagaceae, Sapindaceae, Euphorbiacae

. the high altitude mountains have coniferous forests  with major species such as Keteleeria davidiana, Pinus merkusii, Paramichelia baillonii, Bischofia trifola, Nephelium chryseum,  Fokienia hodginsii,  Podocarpus imbricatus .

. in dry cold high area ( average annual temperature of the coldest month below 100C, annual rainfall between 600-1,200 mm), such as in Mộc Châu, vegetation with main species include: Quercus acutissima,Quercus serrata ,Carya tonkinensis, Engelhardtia colebrookiana. These species  generally grow on dry and shallow soils. Main families are Fagaceae and Juglandaceae.

.in cold, high mountain range, over 1700 m, some major species are: Fokienia hodginsii, Rhododendron sp. as well as Arundinaria sp. and species belonging to Fagaceae, Lauraceae, Theaceae are common. Typical families are Magnoliaceae, Aceraceae, Moraceae, Lauraceae, Fagaceae, Hamamelidaceae, Lythraceae.

. along rivers and streams,  bamboo forest stands are generally present and are a source of income generation for farmers.

4.2  In the Southeast  ecosystem, where there is no land clearing, dense forest with a high canopy and undergrowth is common. Dense forests are found in Ba Ria area, near Vũng Tàu as well as south of Bao Loc plateau. Principal timbers belong to: the Dipterocarpaceae family such as sao (Hopea odorata), dầu con rái (Dipterocarpus alatus), dầu song nàng (Dipterocarpus dyeri), the Lythraceae family such as bằng lăng (Lagerstromia), the mahogony family like gỏ (Sindora cochinchinensis), cẩm xe (Xylia dolabriformis), trắc (Dalbergia cochinchinensis).

4.3  In Central Viet Nam from Quang Tri to Cape Varella near Tuy Hoà, the dense forests have both the species from North Viet Nam such as lim (Erythrophleum Fordi), kiền kiền (Hopea Pierrei), chò chỉ (Parashorea stellata), dáng hương (Pterocarpus pedatus) and the species from the south such as trees from the Dipterocarpaceae family.

 4.4 In the Central Highlands, Dipterocarps forest  may be found in old alluvial soils on terraces west of BanmeThuot, along the Viet Nam-Cambodia border as well as in Cheo Reo plains. This kind of forest has trees which shed leaves in the dry season. Common trees in these forests include trees of the Dipterocarpaceae family such as Dipterocarpus, Pentacme, Shorea and the Combretaceae family such  as Terminalia .

4.5 Along all the coast, in muddy and tidal flats, mangroves are omnipresent, from Quảng Ninh  to Rạch Giá. Main species of mangrove in Viet Nam are: Rhizophora apiculata , Bruguiera cylindrica , Sonneratia alba , Avicennia marina.. Mangroves are very useful for agricultural economy since they are natural habitat for fish breeding and hatching; in addition to that, mangroves  provide a valuable range of resources such as charcoal, firewood and protect the  shoreline  from coastal erosion. Mangroves are home to an incredible biodiversity of fauna: crocodiles, pythons, birds, mollusks, shrimps, macaques, lizards. However, mangroves have been adversely impacted in recent years because of human pressures, including shrimp farming, urban development, tourism, etc. It is urgently required to take action for better preservation and management of mangroves.

4.6 In the Mekong delta, dense forests of Melaleuca cajeputi  which occupy a transitional area of acid sulphate soils, between the saline mangrove forest and more continental forest vegetation, provide an important source of wood (firewood, posts, poles) and non-wood (wild game, fish, honey and essential oils) products for local communities as well as a refuge for wildlife habitat. Unfortunately, with population pressure, a lot of these natural forests is also, like with mangrove forests, subject to cutting and burning every year.

4.7. Man-made forests. 

Due to massive deforestation in the last decades, the government, with help from international organizations, has a program of  afforestation with man-made forests.

Three types of man-made forests are mentioned here :

 .Casuarinas or 'phi lao' have been planted for dune fixation, near villages in coastal plains of central Viet Nam since a long time. Besides stabilisation of these fragile ecosystems, Casuarina forests help farmers other economic products such as fuelwood and poles.

 .Eucalyptus forests or 'bạch đàn' plantations are established on marginal soils, with Eucalyptus camaldulensis the most commonly preferred species by farmers since the trees are generally straight and easy to market.

 .Acacia planting, namely Acacia  auriculiformis  ( keo) and Acacia mangium are widely adopted for planting in Viet Nam. They are becoming increasingly favoured over Eucalyptus as large-scale plantation species since they suffer less leaf pathogen attacks and less water competitive than Eucalyptus. Like Eucalyptus, the Acacia trees are widely used for firewood, poles, shelter and for making woodchips for export. Small sized logs are converted to lumber in village-level saw mills to make furniture.

4.8  Major issues.

Forests in Viet Nam are currently under threat as a result of increasing population, infrastructure development, fire.. Thus, forest coverage had declined from 14 million ha in 1943 (43% of the national territory) to 7.8 million ha in 1981 (24%) to 2.7 million ha (8%) at present (FAO).. By now, with population pressure, forests are cleared every year for growing crops; so Viet Nam's traditional forest sanctuaries have shrunk dramatically over the years. For an expanding economy of 82 million people, the resource base for natural timber production is too small. In comparison with neighbouring countries, Viet Nam has the lowest per capita availability of natural forest land.(0.1 ha). Ecological balance and biodiversity in many watersheds is threatened by population growth, slash-and-burn cultivation, fires during the dry season, logging, reservoirs construction for hydroelectricity and irrigation, as well as economic pressures such as rural poverty, lack of arable land, migration of people to forested regions, fuelwood collection..

Reforestation either through planting or natural forest regeneration, better natural forest management through local rights over forests, strengthening institutional capabilities, agroforestry in sensitive watersheds, utilization in the countryside of biogas for cooking, sedentary farming in the uplands are some concrete measures to alleviate forest degradation. On the other hand, increasing raw materials for further growth in the promising exporting wood furniture industry are necessary, since currently, it must import up to 80% of the materials needed for its production .

5. Fishery and aquaculture resources.

            Fishing and aquaculture production systems are an important component of natural resources in Viet Nam. Export earnings from fish, shrimp and other seafood products totaled about $2.2 billion in 2003 of which 52% was frozen shrimp and is  the fourth biggest export earner of the country after crude oil, textile and garments, footwear but before coffee and rice. Fishery production is heavily concentrated in the southern part of the country which accounts for 80-90% of total volume. Some 80% of the total production is consumed locally and represents about 40-60 % of animal protein consumption in Viet Nam.  In short, this sector contributes to the food needs of the population, provides export earnings and generates employment. Fisheries products comprise those from aquaculture  and from catch in water surface, either in river or sea waters.

5.1 Fresh water fisheries.

Fish in great varieties and abundance are present in inland waters such as rivers, natural lakes and swamps, man- made lakes, irrigation and drainage systems, ponds, estuarine zones. Fish constitute a necessary diet in the daily food of Vietnamese. Fish of the Carp family (Cyprinidae) are the most abundant. The most important genera include Cyprinus (cá chép), Puntius (cá mè vinh), Osteochilus (cá lúi), Dangila (cá linh), Thynnichthys (cá linh bản), Paralaubuca  (cá thiều).

Fish of the group known as catfish (Siluridae) include different species which are widely distributed such as Clarias (cá trê), Kryptopterus (cá trèn).The serpent-heads belong to the Ophicephalidae family with elongated bodies, wide mouth, large heads such as Ophicephalus ( cá lóc, cá tràu). Those fish can live in muddy waters. Fish belonging to the Anabantidae family include Anabas testudineus (cá rô), Osphronemus Goramy (cá tai tượng) and Trichogaster pectoralis (cá sặc).

Common carp (Cyprinus Carpio) and Tilapia nilotica are being introduced in Vietnam and proved to be quite popular now, especially in the Central Highlands which are situated far from the sea and lack of large rivers. Other common fresh water fish belong to Gobidae family (cá bống) and Pangasidae family (cá tra, cá vồ).

            Among the crustaceans in fresh-water areas, different species of prawns such as tôm càng, tôm lửa, tôm bạc, tôm đất abound with the scientific name Penaeus. 

Molluscs are commonly found in rivers and ponds. Different species of molluscs exist such as ốc hường, ốc lèn, ốc gạo with scientific names as Modiola, Mytitus, Nerita..

            Frogs are abundant and some are widely appreciated for eating. Tortoises (Trionix cartilagineus) exist also in the Mekong delta.

5.2    Brackish water fisheries.

Those fish live partly in the ocean and partly in the river for spawning or feeding. They are represented by the well-known sea-bass cá chẻm (Lates calcarifer ) and the milk-fish called cá măng (Chanos chanos). In the brackish water areas such as in the mangrove swamps, many crabs exist. One of these which is very tasty is the large blue crab (Scylla).

Many mangrove swamps in the Central coastal lowlands with brackish water such as near Ba Ngòi and Ninh Hoà areas are locations where farmers raise fish such as cá dìa (Siganus), cá đối (Mugil cephalus), cá hanh (Acanthopagrus herda ), cá măng (Chanos chanos). Brackish water aquaculture - mainly shrimp-  is mostly concentrated in Ca Mau area.

5.3    Marine fisheries .

 Gross output of marine fisheries amounts to more than one million  tons annually . There about 1600 species of marine fish in the coastal waters of Viet Nam, belonging to 200 families and about 100 species are of economic importance.Important marine fisheries are based on shrimps, lobsters, crabs, squid, mackerel, pomfret, sardines, sharks, bream, bass and marine turtles. The coastal waters of Viet Nam abound with fish in great diversity. They are known to the Vietnamese as cá cơm (Stolepborus), cá thu (Cybium), cá bạc má (Rastrelliger), cá thiều (Arius), cá gộc (Polynemus), cá nục (Decapterus), cá trich (Herengula), cá ngừ (Neothunnus), cá dẹp (Engraulis). The Stolephorus fishes are small, slender and semi-translucent  and are used in making high-grade fish sauce.The Polynemus are caught mostly in the coastal waters in CaMau area and exported.

Concerning marine turtles, 5 species occur in the Viet Nam sea. Green turtle Chelonia mydas, Hawksbill Eretmochelys imbicata, Loggerhead Caretta caretta, Olive Ridley Lepidochelys olivacea and leatherback  Dermochelys corjacea but  all  are  quite threatened.

5.4 Aquaculture .

Aquaculture has grown significantly in recent years, averaging over 12% at annual growth since 1990. Aquaculture contributes more than 40% to total fishery production.

Everywhere feasible in the depressions, backswamps, estuaries, lakes.. aquaculture is practised to raise fish or shrimps. In the Mekong delta, ponds are raised with cá tra (Pangasius Pangasius), cá vồ (Pangasius Larnandi ) while in the small ditches in the fruit orchards, there are cá sặc (Trichogaster) or sometimes with cá trê (Claria fuscus), cá lóc (Ophiocephalus). Elsewhere, cá chép (Cyprinus carpio), cá phi (Tilapia mossambica), cá mè (Hypophthalmichthys molitrix) are also raised in hatchery stations. The raising of fish in those ponds represents one of the most intensive methods of land use for protein production and the output is also high. In the average, pond raised with cá tra or cá vồ can give 300kg /100m2 (which is 5o tons of fish/ ha/year). Floating cages very common in Long Xuyên and Châu Đốc are another method of raising fish. Aquaculture production has increased rapidly to around one million tons annually. Most of the shrimp farming is situated in the mangrove areas of Cà Mau, Bạc Liêu and Bến Tre.

5.5 Fish processing.

Fish and shrimps are partly for fresh consumption, partly for processing in various ways. The common methods for fish and shrimp processing are drying, smoking, cooking, frozing. Also fish sauce (nước mắm) is famous from Phú Quốc island. Main fishes used for making nước mắm are cá cơm (Stolephorus) and cá bạc má (Rastrelliger ).  Small shrimp paste (ruốc) is made from very small shrimps such as Acetes indicus, Neomysis, Lucifer hanseni..

The fisheries products for exportation include:  frozen shrimps, frozen cuttle fish, frozen fish, dried fish.

5.6 Main issues related to fishery development are multidimensional:

. overfishing in inland and overexploiting of inshore fisheries by fishermen along the coast's  shallow waters, leading to a rapid decline of fish stocks. Intervention is required to improve management and performance with regard to productivity and biodiversity conservation.

. there is scope  for expansion of offshore fisheries by offering long term bank loans at a low interest rate to enterprises for buying vessels and gears to exploit the offshore stocks of pelagic and demersal fish.

. The main concerns are related to quality and sufficiency of seed and feed supply,  disease control, and management of environmental impacts, including understanding of carrying capacity of sea and inland water areas, extension services, and marketing channels and quality control systems. More emphasis can also be placed on applying aquaculture for poverty reduction. Quality of the product has been a concern in some export markets

. On coastal management, there is need to have a comprehensive coastal zone and integrated planning for improving resource use such as: aquaculture, fisheries, tourism, transport, biodiversity conservation, industry, urban development and energy, since without a planning framework, coastal protection, conservation and allocation of areas for various uses can be significantly impaired.

. oil exploitation, oil spills and leaks from ship collisions and ship wrecks, along with millions of tons of domestic and industrial pollution water, released untreated into the sea, have all further contributed to an alarming decline of the country's marine life.

. rapid coastal population growth on or near shorelines has also damaged vital marine habitats.

. mangrove deforestation, increased salinity intrusion which is correlated with overpumping for irrigation use in the dry season, are also contributing to the degradation of the natural coastal  and marine ecosystems on which much of the  aquaculture depends.

. some mountainous areas have big potential for aquaculture since freshwater is plentiful. Aquaculture could help ethnic minorities a steady supply of protein but it is facing many constraints, due to the scarcity of quality fish seed produced in the region, the difficulties of transportation due to poor access roads, the lack of technical knowledge as well as credit.

6. Animal husbandry resources.

Buffaloes, cattle, pigs, horses, goat and sheep as well as poultry are raised everywhere in Viet Nam. Livestock traditionally plays an important role. Buffaloes and cattle are mainly raised as draft animals and pigs, chicken and ducks are reared for home consumption and cash income. Meat production is roughly with pork accounting for 80% and poultry 13%.

Buffaloes are raised in all natural regions, but comparatively more important in the Northern mountains, while cattle  is important in the plains and in the hills of Central Coastal lowlands where  natural pasture is available. They are used as draught animals in agriculture; buffaloes are used for ploughing, harrowing in the rice fields whereas cattle is for land preparation in upland fields. They are fed with natural  grasses and rice straw. 

Goats . Goats can be fed from a wide range of species, and so they are known as degraders of plant communities. Some areas where goats cannot browse are significantly richer in plant biodiversity. However when they are properly stall fed, goats provide a great opportunity to increase the  income in rural communities.

Pigs. Pigs are raised in many rural households, since they both supply meat to consumers and manure to crops. The pig population, country-wise, is now nearly 30 million heads and is increasing considerably due to avian flu; pig raising is proportionally more developed in the Red River delta than in the  Mekong delta which has a more important  biomass supply (e .g. rice bran, fishmeal, crops left-over, households' wastes ..) than the former. So there is ample scope for increasing the number of pigs in the Mekong delta, thus providing more income generation of the rural population. Besides pig raising at a household scale, one can note the presence of big pigsties, with fast growing foreign breeds  and with scientific management (feed supply, disease control ..)  near the big consuming centers.

The main constraints related to livestock development are: 

- Shortage of feed supply: this is due to the unavailability of feed and fodder, overgrazing, overstocking (increased livestock density per unit of land) and overtrampling which hinder pasture improvement. In the mountainous or hilly areas, valley lands should thus be planted with fast growing fodder grasses such as Napier grass to be used as a cattle fodder to develop livestock production. This will lessen the demand for forest grazing, so helping watershed protection, increase rural income which partially alleviates the need for upland cultivation so that steep land prone to erosion of the watershed can be returned to forest, and provide more manure for cultivated soils, thus increasing soil fertility. 

-Disease improvement : control of livestock diseases such as rinder pest, hemorragic septicemia or Pasteurellosis, blackleg, parasitic gastro-enteritis, parasitic pneumonia, ectoparasitic infestations (ticks, lice and flies), intestinal and blood protozoan infections, viral and bacterial diseases, intestinal worms is equally important to augment production.  For poultry, main problem is Newcastle disease, cholera, avian flu; for pigs, significant diseases are swine fever, erysipelas and paratyphus. Disease problems are, no doubt, related to poor nutrition.

-Less productive breeds: most of the breeds are local due to the lack of capital to purchase breeding stock;  cattle inbreeding often happens since weaning calves are raised in the same herd after they mature; there is need to improve the local breed by crossing with introduced foreign bull or with artificial insemination using foreign semen.

7. Land use.

Of Viet Nam's natural land area of 33.1 million ha (excluding islands), about 8 million ha is currently used for agriculture. Rice is the backbone of the economy. Maize, sweet potato and cassava are supplementary food crops. Fruits and vegetables are increasing in importance. The most important industrial cash crops include coffee (600 000 ha), rubber (380 000ha), tea (79 000ha), pepper (12 000ha), sugarcane, groundnuts, cotton and cashew nuts. These are mainly grown in  upland soils. Livestock accounts for 20% of the agricultural output. The most important activity is pork production covering 80% of the 1.5 million ton meat production.

Agriculture, forestry and fisheries account for 29% of GDP, down from 50% in 1986. Some 75% of the labor force is engaged in this sector.

7.1 Land tenure and land use rights

Before 1980, a cooperative-managed farming system is compulsory and each farming household received a share of outputs according to the recorded  hours of work in coops; inputs and outputs are controlled by government; farmers should sell to the State products with a fixed price, generally lower than the market price; that system gave disastrous results. The agricultural production is thus collectivized and results are food shortage .

From 1981 to 1988, with the introduction of the production contract system, termed 'Resolution 100', the cooperatives can fix production contracts directly with households and each household is allocated with plots on a yearly basis. Agriculture is partly collectivized; inputs are fully controlled and outputs are partly controlled by market forces. The contract system allowed farmers to cultivate individual plots and sell above-quota surpluses on the free maket

From 1988 on, the responsibility of production rests upon each hộ ( farming household).They buy agricultural inputs and sell agricultural outputs wherever they wish to, at the market price. 

The next major reform came with the Land Law which recognized the land-use rights of individual households; the Land Law, promulgated in 1993  allocated lands to individual households for a period of 3 to 15 years on the basis of working labor in the farming household. It also allows farmers to transfer, exchange, lease, inherit and mortgage land ( use land as a collateral for loans) .

7.2 Categories of land use .

Present land use can be of one of these three following categories:

7.2.1 Shifting cultivation.

In this system, land is cleared, forest vegetation is burnt and field crops are planted. The major crops are upland rice (one year) followed by maize or cassava (2-3 years). Most upland rice cultivation is concentrated on slopes where Acrisols, Leptosols predominate. Rice yield is low since it is subject to moisture deficit during certain critical periods of the plant growth and to weeds. After some years, the land is  left in fallow stage, abandoned to shrubs  and only when soil fertility has been restored, land is used back again and the cycle is repeated. No chemical fertilizers are used and very little organic manure is added to the fields. Shifting cultivation is causing serious forest and soil depletion.

7.2.2 Wet rice farming

Rice is grown for centuries from the Red river delta to the Central Coastal plains and in the Mekong delta. Rice is grown either in rainfed or irrigated conditions.

In rainfed ecosystems, rice is sown directly or in nursery at the beginning of the rainy season and harvested beginning in October to December, depending on the maturity of different varieties. It is planted either by direct seeding or single transplanting. Early varieties are grown in middle or upper terraces whereas late maturing varieties are usually grown in the lower terraces where water supply is more reliable but where occasional submergence can also be a problem.

In the irrigated ecosystems, rice is grown in the dry season and gives higher yield, due to high photosynthesis at flowering time. In many parts of Viet Nam, it is called Winter-Spring rice, since it is sown at the beginning of November and lasts to about April. Many improved, dwarf and short duration varieties are cultivated in the irrigated ecosystem.  Rice production is accounting for 90% of total grain output and 78% of the annual crop land. Rice contributes 75% of the calorie intake of Vietnamese households and almost 30% of the value of consumption expenditure. Some 85% of paddy land is irrigated and a portion of it is planted with  hybrid rice varieties, mostly in the Red River delta .

 7.2.3 Upland farming

By upland farming, it encompasses all upland crops which are planted either in rice fields during the dry period or on higher grounds such as on terraces or sloping hills. Field crops, industrial crops (annual and perennial), fruit crops, vegetable crops are under this category.

7.2.3.1 Field crops .

Maize is an important field crop . With 649 000ha alone, it is an important cereal and is grown on fertile, deep alluvial soils or red soils. It is consumed directly as food in various forms: roasted ears, pop corn, cooked ears ..The use of maize in animal feed, particularly for poultry and pigs and in the starch industry is increasing.  Its cultivation extends from the Mekong delta, the red soils of the Southeastern region to the wet hills of North Viet Nam. It is usually grown as a pure crop but occasionally legumes like mung bean (Phaseolus aureus) are grown in intercropping. Average yield of maize is 2.48 tons/ha.

Besides corn, sorghum (Sorghum sp), finger millet (Eleusine corocana ), pearl millet (Pennisetum  typhoides) are also grown in Viet Nam.

7.2.3.2. Root  crops.

Sweet potato, cassava and yams have underground tubers which  have a high starch content .

 Sweet potato (Ipomea batatas) with 255 000 ha is generally planted in rice-based cropping systems and is used for human consumption. Potato (Solanum tuherosum) is grown mostly in the Red River delta, on freely-drained soils of medium to light texture. Cassava (Manihot utilissima) is mostly planted in lands under shifting cultivation systems, with 231 000ha and with an average yield of 7.7 tons/ha. Other root crops which are of economic importance are cocoyam (Colocasia esculenta), yam (Dioscoria spp) and elephant's-foot yam (Amorphophallus campanulatus).. Cocoyam can tolerate poor drainage alluvial soils, hence it is grown on swampy ground. Yams are a demanding crop, only giving high yields where the soil is moderately deep, freely drained, neither very sandy nor a heavy clay.

7.2.3.3 Industrial  crops.

We can distinguish 2 kinds: annual and multiannual industrial crops.

A/ Annual industrial crops such as: sugarcane, groundnut, soyabean, sesame, tobacco, mulberry, cotton, jute ..

. Sugarcane (Saccharum officinarum) is the main source of sugar and is grown mostly in riverine and marine alluvial soils; it is either cultivated in light sandy loamy soils or heavy clay soils. In the former type of soils, it needs adequate irrigation while for the latter type of soils, drainage is necessary. Recent sugarcane acreage is amounting to 350 000ha, producing  a total sugar output of 1 million tonnes in the 1999-2000 crop, thus becoming the 21st country in the world to top the one-million-tonne mark.

. Groundnut (Arachis hypogaea) is grown extensively in sandy alluvial soils, with 269 000ha. Average yield is 1.4 tons/ha. Kernels are also eaten  raw, roasted or sweetened. Many varieties under cultivation fall into 3 groups in respect of the habit of growth, namely bunch (Spanish), semi-spreading (Virginia bunch ) and spreading (Virginia runner).

 . Sesamum (Sesamum indicum), also known as sesame is grown on sandy-loamy soils in the Central coastal lowlands. The sesamum seed is a rich source of edible oil. Its oil content generally varies from 46 to 52%. Its grains may be eaten fried, mixed with sugar like in the famous 'mè xửng' in Huế area.

. Soyabean (Glycine max) occupies an acreage of 127 000 ha and comparatively, it occupies more acreage in the Red river delta than in the south.

 . Tobacco (Nicotiana tabacum) is grown in almost every province and annual acreage is 31 000ha. Viet Nam produces a wide range of types of tobacco and some areas specialize in the production of specific types (thuốc lào, thuốc Cẩm lệ..). Tobacco leaves are cured after harvesting in order to impart the required colour, texture and aroma to the final product. Different methods of curing are adopted for different types of tobacco, depending on the quality requirements and the use to which it is put to. Flue-curing, shade-curing, sun-curing, smoke-curing are different methods of curing .

  . Mulberry (Morus alba, Morus indica ) and silk :

The technique of silk production is an age long tradition in rural Viet Nam for many reasons: the limited availability of land, the limited cash returns have made villages to look for supporting rural industries such as sericulture . Different alluvial areas in the Mekong delta (Châu Đốc) or in the Red River delta are grown with mulberry to produce mulberry silk. Mulberry is raised as a bush plantation and various species of mulberry are raised as main food plants of silkworms. .Bombyx mori, the silk worm, feeds on the leaves of Morus to produce the silk.  Of the total life-span of 50 days of Bombyx mori, the egg stage lasts 10 days, the larval stage lasts longest 25-30 days,the pupa stage takes 10 days. The silkworms pass four moults during growth. The silkworms consume as much as 95% of the food after the third and fourth moults. At the end of the larval duration, the silkworm emits silk from its mouth and constructs a cocoon. For silk reeling, the cocoons are cooked in hot water and the silk fibre is unwound from the cocoons. This cottage industry helps alleviating rural poverty and providing ample work for the rural women rearing silkworms.

 . Jute (Corchorus capsularis), ramie (Boehmeria nivea), sisal (Agave sisalana), cotton (Gossypium hirsutum) are grown. Jute is usually grown in new silty alluvial soils in the Red river delta and the fibre is used for making bags for storing and transporting grains, pulses, spices, sugar..

B/ Multiannual industrial crops  in Viet Nam are rubber, tea, coffee, coconut, pepper.

. Rubber (Hevea brasiliensis) is grown mostly in the Southeastern region (Bình Phước, Đồng Nai provinces) either in big plantations or under small holdings. Acreage devoted to rubber plantation is 380 000ha. Rubber is planted for its latex which is obtained from the bark of the rubber-tree by tapping. Tapping is a process of controlled wounding, during which thin shavings of the bark are removed to induce the flow of latex.

. Tea (Thea sinensis) is an important beverage. The country now has about 79,000 ha of tea, mainly in  northern midlands (Phú Thọ, Tuyên Quang)  and mountainous provinces and in the central highland province of Lâm Đồng. Tea export was 35 000 tons in 1998 valued at 50 million USD. Of the production 62% comes from the northern mountains and 24% from the Central Highlands. Most of the tea is exported to China and Eastern Europe. Production could be increased significantly with improved tea varieties and better crop management and processing facilities.  At present, there are 1,300 tea processing establishments in the country, of which nearly 80 are industrial enterprises, and the rest, handicraft workshops. According to the Food and Agriculture Organization (FAO), Vietnamese tea accounts for 3.5 percent of the world tea market. It is now exported to almost 40 countries and territories in the world. The Middle East is still Viet Nam's biggest tea importer, buying 40-50%, while Eastern Europe, 3%. The  country also exports tea to the United States, Australia  and Taiwan.

 . Coffee is cultivated mostly in the Central Highlands (Darlac, Lâm Đồng and Pleiku). Arabica (Coffea arabica) and robusta (Coffea canephora ) are the two principal economic species cultivated in red basaltic soils. The country has over 500 000 ha of coffee,  with  80% of that acreage in Darlac province. High coffee yield in that area is mostly due to fertilizer use and sprinkler irrigation during the dry season. Coffee is processed in two ways: wet processing and dry processing. Wet processing, by which  parchment coffee is prepared is generally favoured by the market. For the preparation of parchment coffee, fruits should be pulped with clean water, mucilage on the parchment skin removed then drying the parchment in the sun before bagging. In dry processing by which cherry coffee is prepared, fruits are spread evenly on clean drying-ground for 12-15 days in bright weather or be heat dried. Viet Nam is now the third biggest coffee exporter in the world in the 1998-1999 crop year.

 .  Coconut (Cocos nucifera) is a majestic perennial palm and estimated acreage is 169 000ha. It is found extensively on light coastal soils in Bình Định province (Bồng Sơn, Tam Quan areas)  and on raised beds or dikes in Bến Tre province of the Mekong delta. It is mainly cultivated for the nuts from which two important commercial products, copra and fibre are obtained. Copra yields oil and oil-cake. The coconut fibre known as coir can also be used as materials for ropes, mats, nets, bags ..

 .  Cashew (Anacardia) is planted in the South Eastern region .

.  Pepper (Piper nigrum) with 12 000ha is one of the most important and earliest-known spice crops of Viet Nam. It is a perennial climbing vine belonging to the family Piperaceae. The black pepper and the white pepper of commercial use are the dried and processed berries and have a very prominent place in the world market. The pepper vines commence bearing during the third year. Harvesting is  done by plucking the spikes, when one or two berries become red. The spikes are spread on the floor and the berries are separated by  trampling and they are dried in the sun for 4-7 days until the outer skins become black and shrink. This is the black pepper of commercial use.  White pepper is prepared from fully ripened berries by removing the outer rind and the pulp before drying.

 7.2.3.4.  Fruit crops

            Around 300 000ha of fruit crops are grown . In the Mekong delta, fruit crops are planted on alluvial soils along the river levees or on raised beds. The dominant fruit crops are banana (Musa paradisiaca),  mango (Mangifera indica),  longan (Euphoria longana),  citrus fruits (grapefruit, lemon, orange),  guava (Psidium guava),  papaya (Carica papaya),  pineapple (Ananas comosus),  sapota (Achras zapota), durian (Durio zibethinus),  rambutan (Nephelium lappaceum),  mangosteen (Garcinia mangostana),  custard-apple (Annona squamosa) .

In the home gardens of Central Viet Nam, dominant fruits are  jackfruit (Artocarpus heterophyllus). Some areas in the Red River delta are famous with litchi (Litchi sinensis). In the high mountains of North Viet Nam , one can find  apricot (Prunus armeniaca),  apple (Malus),  plum (Prunus domestica), pear (Pyrus communis),  persimmon (Diospiros kaki) .

 The exported fruits include: banana, pineapple, mango, litchi, rambutan, grapefruit, durian, plum, apricot and orange. 

7.2.3.5.  Vegetable crops

Vegetables are mostly being short-duration crops and can be produced in succession on the same plot; there are more than 50 important vegetables which can be dealt under different groups as follows.

Solanaceous fruits which include tomato (Lycopersicon annum), brinjal (Solanum melongena) and  chilli (Capsicum annum), all belonging to the Solanaceae family

  Cole crops which include cabbage (Brassica oleracea), cauliflower (Brassica oleracea),  Chinese cabbage (Brassica chinensis)  are hardy and thrive best in cool weather and belong to the family Cruciferae.

  Root crops such as  radish (Raphanus sativus),  turnip (Brassica rapa), carrot (Daucus carota) are quite common..

  Bulb crops  include  onion (Allium cepa), garlic (Allium sativum), leek (Allium porum).

 Peas and beans such as đậu hà lan (Pisum sativum), French bean (Phaseolus vulgaris), đậu đũa or string bean

Cucurbits crops include cucumber (Cucumis sativus),  muskmelon (Cucumis melo),  water-melon (Citrullus vulgaris),  bottle-gourd (Lagenaria siceraria),  sponge-gourd (Luffa cylindrica),  bittergourd (Momordica charantia), ash-gourd (Benincasa hispida),  pumpkin (Cucurbita moschata), to cite a few .

 Okra (Abelmoschus esculentus) belongs to the family Malvaceae and is a warm-season crop.

  Leafy vegetables, potherbs or greens such as  amaranthus (Amaranthus sp )  Portulaca (Portulaca oleracea).

 Perennial vegetables are those which produce the edible portion continually for several years.The common vegetables under this group are globe artichoke (Cynara scolymus) and Jerusalem artichoke (Helianthus tuberosus) .

7.3 Major issues.

Agriculture is the  backbone of the economy of Viet Nam and there is need to make investments in that field to promote food security, increase exports and create jobs for an increasing population.

Some major issues in agriculture sector are:

.soil fertility problems: due to multiple cropping in the lowlands and low soil fertility in the uplands, fertilizers should be used to intensify agriculture . An in-country fertilizer industry  should be able to produce annually at least 2 millions of tons of urea fertilizer to satisfy the needs while it produces only 500,000 tons of urea fertilizer this year (1999), less than a third of domestic demand. Right now, the production capacity at the majority of fertilizer factories remains low because of outdated technology which has also led to higher prices for local fertilizers in comparison to imports. 

.post-harvest facilities.  The agro-industrial sector still has major challenges ahead. Only 60% of tea, 5% of fruits and 1% of meat are processed. In particular, more investment should be poured into upgrading facilities of the coffee industry,  so as to further raise the competitiveness of the product.  The improvement of post-harvest technology will help raise the value of farm products, generate more jobs, and increase income, thus eliminating hunger and reducing poverty. The development of post-harvest technology will also pave the way for the formation of industrial production and agricultural enterprises in rural areas.

 . small land per agricultural worker. As urban sprawl gobbles up agricultural land in Viet Nam, the Vietnamese farmer gets less and less land for agriculture. On average, a Vietnamese farmer has 0.14 hectares of land for agricultural purposes, while the Asian farmer average is 0.26 ha. Underemployment is thus very high. So, there is need to encourage off-farm and off-the-land income to help the non-agricultural economy in the rural areas, thus alleviating the unemployment in the countryside. Crop intensification, as well as mixed cropping, multiple cropping are required to produce food for a growing population.

. low world market competitiveness. The competitiveness of Viet Nam's agricultural products is quite weak in the international market, due to high production costs and low productivity. Thus, there is need to zoning intensive commodity growing areas, either tea, coffee or sugarcane, diversifying their products and raising their competitiveness.

8. Conclusions.

Overpopulation is creating a shortage of arable land in the delta. The shortage is exacerbated by urban and industrial development that is taking away precious farm property. Off-the-land activities are the solution to that difficult inequation of too many people and not enough land but development should proceed side by side with environmental protection. Some important issues for the agricultural development of  different ecosystems in Viet Nam are discussed belows.

8.1The Northern Mountains and midlands have long been under strong environmental stress. Thirty years ago, those regions were covered with natural forests but with increasing population, deforestation has been a widespread phenomenon. Local needs for food and fuelwood, combined with urban timber and charcoal demand take a heavy toll on forests. Shifting cultivation with shorter fallow periods make lands more unproductive and has caused a severe soil erosion problems, thus inducing food shortage. Moreover, those areas lack infrastructure, health care, education and information on improved technologies.

So, a pre-requisite for development is that the essential infrastructures of health, education, credit and markets are secured.  Low returns to labor and low productivity reduces the volume of surpluses and thus locks the communities into a poverty cycle and reduces the potential to invest in other livelihood options. There is need to  diversification into high value  crops, such as coffee, tea, fruit trees, medicinal plants, spices etc.. since they can bring better returns to labour and improve incomes in upland areas.

On the other hand, the development of employment opportunities in upland towns through rural industrialization and service sector development needs to be addressed, thus helping job creation and increased demand for local goods.

8.2 The Red River delta is always overpopulated and off-farm or off-land activities should be fostered to relieve population pressure on the land. Rural industrialization such as microenterprises development, agroprocessing are thus necessary.

8.3 The Central Viet Nam plains support presently nearly 17  million people, most of whom depend directly on the natural resource base for their livelihood and well-being. It is the poorest region of the whole country.

All watersheds in this ecosystem are threatened by population and economic pressure while they are critical for downstream investment in hydro-electric and irrigation schemes, such as protection from flooding, siltation and salinity intrusion. Watersheds play also an important role in wood and timber supply. Integrated development of the watersheds help income generation of the population, mainly ethnic groups who suffer a high degree of food insecurity .

8.4 In the Central Highlands, the existing productivity of present land use systems is very low. There is ample scope for introducing more productive systems, especially in the underutilized valleys and plains which lie around the lakes (e .g. Lak in Darlac) or rivers (Bla and Dak Poko in Kontum, Ba river in Gia Lai, upper Srepok in Darlac watershed..), through irrigation as well as with external inputs to increase food production, so that there is no incentive for villagers to practice shifting cultivation which will result in a loss of biodiversity and soil erosion. Wherever possible, the development of small-scale power plants using renewable energy resources (wind, water, solar) is very important in accelerating socio-econonic development of mountainous people in the remote areas which cannot be connected with national electricity grid network.

8.5 The Mekong delta's  agriculture, which accounts for nearly 30% of national GDP, 50% of rice production of the whole country, is the main rice exporting area. Sustainable development of the Mekong Delta is central to achieving the country's targets for sustained growth. There is  scope for rapid economic growth, increased agricultural diversification into high value crops such as vegetable, floriculture, fruit crops as well as aquaculture for increased exportation .

Above all, in all those ecosystems, a policy of birth control/family planning should be seriously and relentlessly pursued to master overpopulation problem which is the root cause of environmental degradation. Rapid population increase, with a perspective of 140-150 million inhabitants in the middle of next century in combination with dwindling natural resources will lead to environmental degradation, resources depletion and reduction in food availability per capita. Also, urgent domestic challenges of inequality, social cohesion and corruption should be tackled.

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