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Annex XV



In South and South East Asia and the Pacific, it is estimated that an area of more than 13 million hectares of agricultural land are prone to floods. These occur mainly in Bangladesh, India, Burma, Thailand, Vietnam and Cambodia and are caused primarily by an accumulation of rainwater, river discharge to basins forming deepwater bodies, and tidal movements. The Ganges, Brahmaputra, Irrawady, Chao Phraya and Mekong rivers are responsible for the major floods of Asia. Their depth and duration determine the kind of traditional deepwater and/or modern varieties of rice (the pre-dominant crop) and the range of other crops that are being grown. Over the years, people in and around flood-prone areas have developed a unique way of life and adopted a complex farming system involving crops, livestock and fisheries that can accommodate this natural disaster. Comparatively recent innovations with water control structures and the application of research-based technologies have led to significant advancements in farming systems, and consequently, the livelihood patterns of people inhabiting such areas. They have created a favorable environment mainly for rice cultivation. The use of high-yielding varieties and modern agricultural practices have improved food security, created additional employment opportunities and uplifted the socio-economic conditions of the rural population. However, the rate of progress has not been as substantial as in non flood-prone areas. Unfortunately, some of the new technologies had a negative impact on the environment and on those who adopted them. They are responsible for a reduction in fishing and livestock production and adversely affecting dietary habits and living standards.

Despite some disadvantages, this paper postulates that improvements in the farming systems of flood-prone regions are of vital importance, as large populations in such terrain are dependent on agriculture for their survival. It is not possible for man-made structures to eliminate floods, they can only assist in controlling them. Therefore, engineering and agronomic measures together with the farmers' indigenous knowledge are needed to bring about progress. A participatory systems approach that encompasses crops, livestock and fisheries is an essential pre-requisite to sustainable and environment friendly development.


1. Flood is part and parcel of living for a large number of people in Asia and the Pacific. It is a regular phenomenon particularly in such countries as Bangladesh, Myanmar, Thailand, India, Vietnam and Cambodia, where the loss of human lives, natural resources, crops and livestock have at times destroyed the financial backbone of farmers. There are about 31 million hectares of flood-prone areas in South and South East Asia, of which 13 million are used for agriculture, mainly for the planting of some form of deepwater rice (Singh, et. al. 2001).

2. Flood is defined as the inundation of the land surface and it is caused by seasonal accumulation of rainwater, river discharge or tidal phenomenon. Flash floods also occur because of unexpected rainfall, excessive river flow, cyclonic storms and tidal surge. Many parts of Asia and the Pacific are prone to them. They take place without prior warning but last no more than 10 days, and can be due to a number of factors such as unexpected high rainfall, tidal movement, and breaches in flood control structures. Huke and Huke (1997) classify areas as flood-prone when they are under more than one meter in water. Amin and Iqbal (1993) group floods in Bangladesh into three general categories:

  1. normal ones which regularly inundate about 20 to 30 per cent of the country and where loss to crops or livestock is minimal,
  2. medium ones which inundate about 30 to 40 per cent of the country usually every few years and cause limited damage, and
  3. great ones that may inundate more than 40 per cent of the country and bring about immense destruction.

3. People have, despite such adversity, developed unique farming systems that are able to generate food, feed and employment opportunities. They have devised mechanisms capable of coping with floods that recur regularly in low-lying areas. Governments have also adopted large-scale measures to control them so that such land can be made suitable for risk-free agriculture and other economic activities.

4. This paper attempts to describe the nature and causes of floods in some of the countries in Asia and the Pacific. However, it focuses more on Bangladesh, the country most vulnerable to this natural calamity in Asia.1

1.1 Why, When and How Floods Occurs

5. Floods are caused by an accumulation of rainwater or when the groundwater table is raised due to drainage congestion in rivers. Monsoon rain in watersheds also causes rivers to rise uncontrollably and when they reach the flat topography of the flood plains and deltas, their flow rate, which is dependent on gradient, slows down considerably. Spills of turbid and silt water over their banks begin to inundate the terrain. Usually, rainfall is also high and the clogged rivers prevent most of it from draining away. Thus a large part of the local precipitation accumulates on the land and causes clear-water flooding. Tides are also another contributing factor. A high and low tide occur daily and they may have widespread effect on the environment. Cyclonic storms bring flash floods to coastal areas, particularly in India, Bangladesh and the Philippines. It is believed that rising sea levels due to global warming may place large parts of Bangladesh and Maldives under water.

6. In most Asia countries, inundation takes place from June to October each year, with the maximum depth occurring from August to October (Table 1). The waters from Asia's great rivers, namely, the Ganges, Bhamaputra, Mekong and Irrawaddy, originate from melting snow and glaciers in the interior of the continent, starting in March and continuing to October. In the case of the smaller ones such as the Chao Phraya and the Red Rivers and those from lower altitudes, they are from rain in the catchment areas.

Table 1.
Flood Prone Ecosystem in Asia


Flooding Depth
(30 to 1 M)

Flooding Depth
> 1.0 M

Total Flood-Prone
(Per cent of Rice Area)


Mid 1990s


Mid 1990s


Mid 1990s











































Source: Huke, R.E. and Huke, E.H. 1997.

7. The mean duration of the total flooding period is 140 days in Bangladesh and 120 days in Thailand. Flooding exceeded the 0.5 meter and 1.0 meter thresholds for 120 and 100 days, respectively, in Bangladesh. The corresponding duration was 100 and 40 days in Thailand, but it was considerably shorter in West Bengal.

8. In Bangladesh, surface contour determines the extent of flooding in an area. The floodplains of the Ganges, Brahmaputra, Tista, Surma, Kushiara and other rivers and tributaries occupy about 70 per cent of the country. In most years, 30 per cent of Bangladesh's cultivated area is covered with more than one meter in water, and 5 million hectares are inundated from 0.3 meter to more than 3.0 meter. Monsoon rains in the watersheds cause the rivers to swell up uncontrollably.

9. Vietnam and Cambodia share a severely flooded Mekong river basin. Its system includes the Great Lake that acts as a buffer reservoir during extremely high and low flows of the Mekong River, and it contains one of the world's richest freshwater fishing grounds. Pre-monsoon rainfall and flooding patterns are more erratic in Cambodia than in the Vietnamese part of the delta. North Vietnam's Red River has perhaps the oldest embankments, where large-scale deepwater rice planting was practiced as far back as the eleventh century (Sakurai, 1980). Although there is now an extensive system of dikes and polders to control the water level, the pumping system is unable to handle periodic depressions and typhoons that bring exceptionally heavy rainfall.

10. The major flood prone areas in India are located in the east, namely, in eastern Uttar Pradeh, West Bengal and Orissa (Singh, et. al. 2001). There are approximately 2.30 million hectares of such land in the Ganges-Bramaputra basin. Despite efforts made to control floods, evidence exists to indicate that their frequency is increasing. Those in Bangladesh and India are caused by deforestation of the Himalayan foothills in Nepal, and this is responsible for erosion and excessive silting of riverbeds and erratic rainfall patterns. The rural network of roads in Bangladesh also prevents proper drainage and this leads to frequent occurrence of local flooding.

11. Although people in such areas have developed farming systems that adjust to the timing and duration of floods, their unpredictability can cause immense loss to crops, livestock, fisheries and other properties. Efforts to control them have often failed to produce the desired results. Sometimes, they have disturbed the way of life of the rural folk and further aggravated malnutrition and poverty levels in certain cases. This proves that flood mitigation steps to be developed, must take into account the farmers' traditional wisdom and farming methods developed by them to cope up with floods.


12. Deepwater rice is sometimes planted on the margins of large depressions or bils in Bangladesh and eastern India, where flooding is experienced up to nine or ten months of the year. Its duration is a month or two less in most regions where traditional tall cultivars are grown, and in transitional areas where the floodwater is not expected to rise above 0.5 meter for more than one to two months.

13. The Chao Phraya delta in Thailand has probably the most sophisticated water control system in the region. It comprises a network of canals, dikes, channels and large storage dams built over the last hundred years. It has the advantage of adequate gradient to distribute fresh water by gravity from its headwork located near Chainat. The system also includes large-scale irrigation and hydroelectric power generation at several large upstream reservoirs and protective dikes around Bangkok. Early and late season water levels are usually well controlled and they benefit rice farmers considerably.

14. The Mekong and Irrawaddy deltas were sparsely populated, inaccessible and unhealthy a hundred years ago, and in both of them the first canals were dug primarily to improve transportation. The gentle slope of the former makes flood protection very difficult. Water distribution is not possible by gravity alone, and during the dry season, the tidal effect is felt as far up the river as Phnom Penh situated nearly 200 km from the sea. Flood control measures in the Cambodian lowlands are less developed and most of the shallow canals were built with great suffering and loss of life during the Khmer Rouge period. There are no storage dams on the Mekong itself and those on its tributaries have little effect on river flow during the monsoon season. However, feasibility studies carried out on the construction of a series of massive storage dams, called the `Mekong Cascade', show that a potential exists for more effective flood control, increased irrigation capacity and the generation of hydroelectric power (Mekong Committee, 1988).

15. Attempts to control floods in the Ganges-Brahmaputra basin have been largely unsuccessful, despite the erection of several thousand kilometers of embankments, drainage canals and protective earthworks on the two main rivers and their major tributaries. Since the fourteenth century, water has been diverted from the upper Ganges to irrigate the fertile Ganges-Yamuna doab (Stone, 1984), and there is now a barrage across the river at Farakka near the Bangladesh border. However, violent discharges of the Himalayan streams continue to cause extensive crop damage and loss of life. The Kosi River of north Bihar is the worst hit. No attempt has, so far, been made to curb the flow of the Brahmaputra by dam or barrage, and as a consequence, it has brought disastrous floods to the Assam Valley and Bangladesh in 1987, 1988 and 1998.

16. In 1870, most of the Mekong delta was a vast inaccessible forest swamp that was sparsely populated by pioneer farmers who planted rice and fished in its abundant waters. However, since the last decade, considerable development has taken place along some of the main river branches in the Vietnamese delta. Fresh water pumped from an irrigation-drainage system directly on to the land and low embankments to delay flooding, is extending the cropping season and making double cropping possible (Mekong Committee, 1988).

17. Fishing is second only to rice culture in the Mekong delta and floodplains. (Pantula, 1986b). It directly or indirectly involves 25 per cent of the population and supplies 40 to 60 per cent of the animal protein. In 1973, the annual fish production of the Lower Mekong basin was estimated at about 0.5 million tons (Mekong Committee, 1988). Although its fish fauna is very rich, only about 10 species are well known to fishermen.

18. In Cambodia, no detailed hydrological records on flooding of farmers' fields are kept. A vast area below Kratie, around the Great Lake and on the plains of the Tonle Sap and Mekong River and its tributaries, floods every year. Compared with Vietnam, the occurrence here is earlier and more severe, and the cultivation of floating rice is more risky because of rapid inundation.

2.1 Flood Prone Cropping Patterns in Cambodia

19. There is no recent account of this in Cambodia. It appears that most deepwater rice lands presently practice mono cropping. In the southern Cambodian delta, some farmers plant deepwater rice in the back swamps and grow a partially irrigated rice crop on higher land, i.e., on the slopes of levees (Fujisaka, 1988). In Kandal province, farmers combine crops such as maize with deepwater rice, while some plant sesame and mung bean in rotation with floating rice, and in Prey Veng, attempts are made to replace the standard floating rice fallow pattern with two short-duration modern rice varieties, as in the case of Vietnam (Puckridge, 1988).

2.2 Flood Prone Cropping Patterns in Vietnam

20. Here, severely flooded areas have undergone dramatic changes over the last 20 years. Broadcast deepwater rice is the dominant crop in the Trans Bassac Horst region that usually floods less than one meter. Three factors are responsible for recent innovations in their cropping patterns, namely:

  1. the introduction and adoption of modern rice cultivars,
  2. the digging of new canals to carry fresh water for irrigation, and
  3. the proliferation of low lift sampan pumps.

21. The following cropping patterns are practiced in the flood prone areas of Vietnam;

  1. rice-rice-fallow,
  2. broadcast floating rice (traditional mono cropping),
  3. broadcast floating rice - soybean + maize, and
  4. transplanted floating rice with pre-flood kenaf.

22. In the early eighties, the provinces of An Giang, Dony Thap and Northern Hau Giang in the Vietnamese delta have integrated the planting of deepwater rice with upland crops. The latter include sesame, mung bean and soybean and are planted with zero tillage on non-acidic and moderately acidic soils, immediately after the harvesting of floating rice, using stubble as mulch. Several such crops together with maize and cowpea are mixed with floating rice in the pre-flood period. Many radical changes including the replacement of deepwater rice (monocrop) by two modern varieties has taken place in An Giang, Dong Thap, Long An and Kien Giang provinces. In deeply flooded regions, the double-cropped area extends to both sides of the main canals for a distance of about 5 km. However, traditional mono cropping of floating rice persists along the river.

23. Multiple cropping has clearly made an impact on the income of farmers in these deepwater regions. Compared with a single, floating rice crop, double cropping with modern cultivars gives three to seven times higher net return, followed by maize (2 to 3 times higher) and sesame (2.0 to 2.7 times higher) (Huynh, 1989).

24. In Dong Thap province, fish production declined to one-tenth of its previous level when floating rice was replaced by two irrigated modern varieties (Puckridge, 1988). This is probably due to the removal of natural fish habitants and the effects of fertilizers and pesticides. To compensate for this loss, there is a move to build ponds to rear fish.

25. In the Red River basin of northern Vietnam, deepwater rice was introduced as |a wet season crop. Early flooding sometimes destroys the newly transplanted crop and in very wet years, it may have to be replanted several times. This results in very low yields or complete crop failure (Kanter, 1981b). Submergence tolerance remains a useful trait for new cultivars developed for these areas.

2.3 Flood Prone Cropping Patterns in India

26. Deepwater rice is a predominant crop in the flood prone areas of India. There is little genetic erosion in such terrain in eastern India because of the release of only a few high yielding varieties for planting (Singh, et. al. 2000). The rate of replacement with new ones is slow due to poor seed distribution and farmers' preference for specific traits. This is the case in the rain-fed lowlands and more so in deepwater areas. However, in more favorable sections of the latter, modern varieties have started to make an impact. Farmers only adopt them in carefully chosen fields that can provide a good harvest and they also manage the crop better. They have as yet to make inroads in flood prone deepwater terrain. In these areas boro-season rice gives a higher yield and more profit to farmers ( Thakur and Singh, 2000).

2.4 Flood Prone Cropping Patterns in Bangladesh

27. In Bangladesh, land is classified according to flood depth; highland (above flood level), medium highland-1 (up to 0.30 m in water), medium highland-2 (up to 0.90 m in water), medium lowland (up to 1.80 m in water), lowland (up to 3.00 m in water) and low lowland (more than 3.00 m in water) (FAO/YBDP, 1998). About 1.01 million hectares of flood prone land in the country practices the following seven cropping systems; (i) fallow-T. aus-T. aman, (ii) fallow-B. aus-T. aman, (iii) fallow-T. aman, (iv) fallow-DW aman, (v) fallow-B. aus+B. aman, (vi) boro-fallow-T. aman, and (vii) boro-fallow-fallow where opportunities exist to cultivate non-rice crops during the rabi season.

28. It is possible to increase the planting area, but market demand and price should be considered when making recommendations for such an environment. Research conducted by the Bangladesh Rice Research Institute (BRRI) proved that it is feasible to cultivate non-rice crops in the short fallow period (of about 70 days), after the T. aman harvest and before boro rice transplanting in the boro-fallow-T. aman system (Elahi, et. al. 1999). Potential crops identified for planting during this period are potato, legume vegetables, and mustard. Approximately 0.17 million hectares of land left fallow for 70 days in the boro-fallow-T. aman system can thus be planted with a non-rice crop.

29. In flood prone areas, farmers practice various farming systems that include wheat, potato, mustard and other rabi crops in their farms. The yield is low. However, it is higher at research stations where up-to-date management practices are followed. The application of modern technologies at farm level would undoubtedly increase productivity to a greater extent (Table 2).

Table 2.
Changes in Cropping Systems in Bangladesh and Yields


Per cent of Land Under Crop

Yield Rate (kg/ha)





Per cent Change







Aus TV






B. Aman TV






T. Aman












Other crops:
















































Cropping Intensity
















30. In 1987/88, traditional low-yielding deepwater broadcast aman rice was the major crop in flood prone areas and it occupied nearly two-thirds of the rice land, followed by traditional aus rice that was grown as a mixed crop with the former. Rice planted in similar regions during the dry season is called "boro". Modern varieties gave almost 2.8 times higher yield than aman. With the rapid expansion of irrigation facilities, boro increased to 52 per cent of the cultivated land by 1999-2000. As the area under it grew, the land allocated for most dry season crops, particularly pulses and oilseeds declined substantially (Hossain, et. al. 2001). A major cropping pattern in flood prone areas was mixed aus aman relayed with pulses or oilseeds or a double-cropped aus-aman (Table 3). These have almost disappeared in favor of the single cropped boro.

Table 3.
Changes in Cropping Pattern
(Per cent of Cultivated Land)

Cropping Pattern


















Aman-MV Boro









31. Inundated lands cover about 4.9 million hectares, of which, an estimated 4.5 million hectares are cropped (Elahi and Khan, 2001). In such terrain, no other non-rice crop except jute can be grown during mid-April to mid-October (kharif season). Various flood control measures implemented in Bangladesh have brought positive results. They have, in many places, created a favorable environment for agriculture, particularly for the cultivation of dry season rice and other crops. Large acreages, previously devoted to a single, deepwater winter crop such as Lathyrus, field pea, and local varieties of boro or left fallow, are now cropped with high yielding varieties (HYV) of winter rice and other suitable crops. This has produced a tremendous impact on self-sufficiency in cereals and also on the rural economy by creating new employment and agro-business opportunities in Bangladesh.

32. Although the availability of land for agriculture has been declining, its productivity has increased due to the rapid expansion of irrigation facilities and the adoption of modern rice varieties during the dry season. The area under local varieties, on the other hand, has declined substantially over time, as farmers grow the former during the dry season and leave the land fallow during the wet season. Nearly 46 per cent of the land was under this system in 1999-2000, and this has reduced cropping intensity.

33. A major change in livelihood as a result of these farming innovations is the declining dependence of poor households on the agricultural labor market. The number of agricultural workers has almost halved over the 1988-2000 period, due to rising employment opportunities in the non-farm rural sector. This has resulted in a rapid adoption of agricultural mechanization in land preparation and a higher incidence of tenancy.

34. Although the yield increase for individual crops has been moderate, that for rice has been substantial because of the switch from planting low-yielding aus and deepwater aman to high yielding boro. Such productivity growth has, however, not been translated into higher farm incomes because of the much slower rise in paddy prices compared to those for workers and fertilizer. The nominal wage rate is almost at par with the consumer price index, but because of the sluggish increase in the nominal price of paddy, the entitlement of staple food for land-poor households has improved markedly.

35. Rice, however, constitutes a tiny share of household income because of the very small size of farms and the unfavorable price of the commodity. Per capita income rose by 3 to 4 per cent per year due largely to rapidly expanding incomes from non-agricultural sources such as trade and business, transport operations, services and remittance from abroad. The transformation from a farm to a non-farm rural economy has been facilitated by improvements in human capital and the development of rural infrastructure, particularly roads. The rapid advancement of the non-agricultural sector has alleviated overall poverty, although in absolute terms, its level remains very high. The improvement is more pronounced for households who derive their incomes from services and trade and only marginal for farmers and day laborers.

2.4.1 Changes in Livelihood Systems in Flood-Prone Areas of Bangladesh

36. In 1987-88, more than 60 per cent of the population was dependent on agriculture; 36 per cent working on their own farms and 24 per cent as paid labor in other farms. Very few were engaged in fishing or livestock production as their principal occupation. This dependence has however dropped to a large extent over the period, as rural off-farm activities grew in importance. In 1995, 51 per cent of workers were employed in the non-agricultural sector, i.e., in various salaried and personal services, petty trading, shop keeping, business, agro-processing, transport operation and road and house construction. The number of farmers remained almost the same, but that of agricultural wage laborers had declined noticeably from 24 per cent in 1988 to 13 per cent in 2000 (Table 4). It indicates that the migration from rural to urban centers is most pronounced among land-poor groups who were initially employed as agricultural wage laborers, but have increasingly sought work in the service and trading sectors. The mobility of the labor force out of agriculture was facilitated by improvements in rural roads and human capital, and technological progress in rice cultivation that generated employment opportunities in trade, transport and marketing of agricultural inputs and the disposal of marketable surplus. As a result, labor scarcity is emerging and it caused a greater use of piece-rated contracts for conducting specific agricultural operations (transplanting, weeding and harvesting). This change had a positive impact on daily wage earnings.

Table 4.
Distribution of Working Members by Occupation (Per cent)


Primary Occupation

Primary & Secondary Occupation















Agriculture labor





Other agriculture










Trade & business










Other non-agriculture










37. Progress in rice technology can only make a limited contribution towards increasing household income. The role of research to enhance rice production should focus on increasing supplies and reducing its unit production cost so that its price can be maintained at affordable levels for both the rural and urban poor. Since a large proportion of land in flood-prone countries remains single cropped, options to introduce double cropping should be explored by developing shorter duration and cold tolerant aman and boro varieties.

38. Flood control structures have, on the other hand, disturbed traditional farming systems (Sultana, et. al. 1997; Hoggarth, et. al. 1999; De Graff, 1999) that produce pulses and oil-seeds and provide open access grazing for livestock. They have thus a negative effect on soil properties (Alexander, 1998). Traditional flood-prone, low-lying areas that housed milk-sheds, were sources of open water fishery, and give employment to fishermen and milk processors were replaced by rice and other high value crops. Grazing areas and those that grew lathyrus as a major forage and pulse crop were also taken over. This has greatly reduced the cattle population and availability of milk and cow dung, a traditional source of organic manure and fuel in Bangladesh. Flood-control structures and the use of chemicals in rice cultivation have also significantly reduced fish availability.


39. The indigenous population has, over time, developed unique farming systems and other mechanisms to accommodate floods. In fact, farmers often do not perceive themselves as suffering from their occurrence, and annual inundation to a certain depth has became part and parcel of daily living. Houses are built on elevated land, crops and cropping systems are adjusted and transportation fits in with the flooding pattern. Culture and agriculture are subjected to the dictates of floods and the human demand for food.

40. Basically, two strategic options exist to improve the productivity of areas that enjoy flood protection (Brammer, 1988). One, is the engineering approach where embankments, dykes, sluices, etc. are erected, and the other is agronomic in nature and involves the introduction of new farming systems such as high yielding varieties that would mature and be harvested prior to the onset of floods. Another would be to combine the two and this would give a wider choice to farmers.

41. Post-monsoon drainage is the most critical factor governing crop productivity in the northeast region of Bangladesh. Relatively short duration high yielding rice varieties (such as BRRI Dhan 28 and BRRI Dhan 36) are currently available to farmers. If excess water can be drained out by January each year, transplanting with 60-day old seedlings can be completed. Thus, a 140-150 day rice crop yielding 5-7 tons per hectare of paddy can be harvested by the end of April. This minimizes the danger of crop damage by flash floods and ensures a safe harvest. More higher yielding, cold tolerant varieties that mature early are needed for these areas. This can be achieved by research on appropriate breeding processes that help to reduce the rice growing period.

42. Crop damage by flash floods can be minimized by the construction of proper submersible embankments, with adequate provisions made for drainage and navigation. However, the responsibility for operating and maintaining them can be transferred to farmer groups in a planned manner. Following this, they can then adopt appropriate technologies to improve the productivity of this area.

43. Two basic development strategies can be adopted to increase agricultural production in flood-prone regions. The first is the provision of flood protection, and the other, is to improve crop production in a status quo environment. The latter is, on the whole, simple and less costly than the former. Modern technologies to overcome floods are only available for the boro season. Their adoption is highest in the country (93.78 %). However, none exists for deepwater rice that covers about 15 per cent of the net cultivable area. Major environmental concerns in rice cultivation relate to three factors, namely, (a) the heavy use of agrochemicals with its adverse effects on human health and water quality; (b) the erosion of biodiversity caused by the adoption of a few profitable modern varieties; and (c) the decline in soil fertility due to intensive rice monoculture (Pingali, et. al. 1996; Bose, et. al. 2000). The limited data available from surveys indicate that these concerns are not currently major problems for the flood-prone regions of Bangladesh.

44. As rice is the predominant crop in such areas, the BRRI has taken great effort to try to develop a deepwater variety that would give higher yield, but it has as yet to succeed. However, other aspects of research to improve the production system were attempted. The results from them indicated that boro varieties grown in deepwater terrain should use extensive irrigation and other up-to-date practices such as integrated pest management. The dapog method of seedling production could be promoted and quality seed production of existing popular deepwater varieties undertaken. Boro followed by transplanted deepwater types should be expanded whenever feasible. Early maturing varieties to avoid flash-flood damage at maturity stage should be developed. In some areas, modern technologies for maize, pulse and oilseed production are absent. There is thus an urgent need to introduce and popularize them.

45. To offset the negative effects of flood control measures on the fishery industry, cage fishery and rice-cum-fish rearing could be introduced. Fast growing fish species should be recommended and fingerlings distributed. The integration of fish with poultry is economically viable and could be another option for farmers.

46. The creation of a favorable environment for rice could have a tremendous impact on livestock. The reduction of grazing land and the introduction of power tillers to meet the growing demand for timely land preparation due to increased cropping intensity, have caused the livestock population to diminish. This could be replaced by the production of forage crops and milk, and duck rearing.


47. In Bangladesh, the environment itself is a major constraint to the adoption of not only modern, but, traditional technologies in food-prone areas. A great part of the country is inundated every year and this brings with it various types of damage. The recent devastating flood of 1998 resulted in the highest loss of paddy that was estimated at about 3.0 million tons (Mastafi, et. al. 1999). The two most important factors that govern crop production are flood depth during the monsoon season and the probability or frequency of a sudden rise in the water depth, or the onset of flash floods and storms. The constraints encountered can be grouped as either physical, biological or socio-economic in nature.

4.1 Physical Factors

48. Flood and drought are the two major physical calamities that destroy crops. The submergence of the rain-fed lowland crop (T. aman) during its early growth phase and the irrigated crop (boro) during the maturity stage is very common. Drought during early growth is very frequent in Bangladesh. Declining soil fertility is another important setback. Organic matter content, its main indicator, has deteriorated in many places to as low as less than 1 per cent, whereas good soil should have 3.5 per cent. More than 60 per cent of the net cultivated area has a content of less than 1.7 per cent. In addition, zinc and sulfur deficiencies have shown up in 4 and 2 million hectares, respectively (Das, 2000).

4.2 Non-Availability of Improved Plant Type

49. For the T. aman variety, a submergence tolerance of at least 7 days is needed in areas that are covered with moderate to deep stagnant water. Varieties with characteristics such as tall seedlings, intermediate to tall plants, sturdy culms without elongation, moderate tillage with 8 to 10 fertile tillers and photoperiod sensitive characteristics are required.

50. For the deepwater variety, the desired characteristics are drought tolerance at the seedling stage, inter-node elongation, kneeing ability, photoperiod sensitive and high panicle density and weight. The following are the prevailing constraints to this variety;

  1. non-availability of good quality seeds,
  2. lack of tolerance to existing major diseases and pests,
  3. farmer's traditional method of seed selection and storing, and
  4. poor maintenance of seed purity.

51. The following socio-economic factors inhibit development;

  1. non-availability of improved cultivation technology,
  2. non-availability of fertilizer and other inputs,
  3. non-availability of credit to poor farmers,
  4. small land holding/farm size/tenure status,
  5. lack of adequate technical knowledge on the part of farmers,
  6. farmer's experience with persistent natural disasters and crop failure deters them from investing more in agriculture, and
  7. incentive for investment in flood-prone areas are lacking.


52. Flood has been part and parcel of life for many people in the Asia and Pacific region. It indirectly affects even those living outside of flood prone areas. Farmers have developed different kinds of farming systems and a unique way of life to cope with floods that vary in depth and duration. Their special understanding of this natural adversity and its consequences have helped them live with it and adopt the kind of farming that is suited to it. Culture and agriculture in flood-prone areas blend to produce a lifestyle that is peculiar to such environment. However, floods to this day pose a constraint to increasing food production and overall economic advancement.

53. Human interventions to control them have produced many beneficial results on agriculture and the standard of living of people affected by them. They have helped expand food production to keep abreast with population growth. Flood control and irrigation and drainage structures often enhance the environment, contribute towards risk-free crop production and increase cropping intensity, use of high yielding and modern technology.

54. But such structures have also created negative impacts. They change farming systems and reduce resource poor farmers' accessibility to nutritious food. In many cases, they deteriorate soil fertility that in turn will adversely affect the sustainability of increased production and natural resources. The main reasons for such adversity are a lack of understanding of the circumstances and requirements of farmers and their priorities, and ignorance of indigenous technical knowledge.

55. Since the demands for improved production and the need to save farmers from losses caused by floods will continue to intensify, it is vital that rehabilitation and mitigating and control measures are designed with the active participation of farmers - both men and women. Such participatory diagnosis, planning and implementation are expected to lead to the development and maintenance of sustainable systems.


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Amin, S. and Iqbal, A. 1993. Coping with Flood Damages and Essentials for Agricultural Rehabilitation. Bangladesh Agricultural Research Council. Dhaka, 24 pp. (in Bangla).

Bose, M.L., Isa, M.A., Bayes, A., Sen, B. and Hossain, M. 2000. Impact of Modern Rice on Food Security and Cultivar Diversity: the Bangladesh Case. IRRI. Los Banos.

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* Prepared by Mohammed Abdur Razzaque, National Coordinator, Farming Systems Research and Development Programme, Bangladesh; and Mohammed Zainul Abedin, Abedin International Inc., Canada.
The views expressed in this paper are those of the authors' and not necessarily those of FAO.

1 The recommendations contained in it do not necessarily reflect those of organizations that the authors work for.

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