Traditional rice-fish systems as Globally Important Ingenious Agricultural Heritage Systems

P. Koohafkan ^a and J. Furtado^b
a Chief, Land and Soil Fertility Management Service, FAO, Rome, Italy ^b Retired World Bank Expert, Consultant, United Kingdom

GLOBALLY IMPORTANT INGENIOUS AGRICULTURAL HERITAGE SYSTEMS (GIAHS): DEFINITION AND EXAMPLES

In many countries, specific agricultural systems and landscapes have been created, shaped and maintained by generations of farmers and herders, on the basis of the diverse species and their interactions and using locally adapted, distinctive and often ingenious combinations of management practices and techniques. Building on dynamic local knowledge and experience, these ingenious agri-"cultural" systems reflect the evolution of humanity, the diversity of its knowledge and its profound harmony with nature. They have resulted not only in outstanding aesthetic beauty, maintenance of globally significant agricultural biodiversity, resilient ecosystems and valuable cultural inheritance but, above all, in the sustained provision of multiple goods and services, food and livelihood security and quality of life.

Globally Important Ingenious Agricultural Heritage Systems are defined by FAO as follows:

Remarkable land-use systems and landscapes, which are rich in biological diversity evolving from the ingenious and dynamic adaptation of a rural community to its environment, in order to realize their socio-economic, cultural and livelihood needs and aspirations for a sustainable development.

GIAHS throughout the world testify the inventiveness and ingenuity of people in their use and management of biodiversity, inter- and intraspecies dynamics, and the physical attributes of the landscape, codified in traditional but evolving knowledge, practices and technologies. Ingenious agro-ecosystems reflect human evolutionary transitions, intimately linking sociocultural systems with biophysical systems. They use traditional knowledge systems, "trial-and-error" and experimental learning, insight and innovations. Their ingenuity has resulted in resilient agro-ecological systems in marginal, extreme or very specific ecologies. These systems are organized and managed through highly adapted social and cultural practices and institutions. Annex 1 (p. 74) illustrates some examples.

Such agricultural systems can be found, in particular, in highly populated regions or in areas where the population, for various reasons, has had to establish complex and innovative land-use and management practices due to, for example, geographic isolation, fragile ecosystems, political marginalization, limited natural resources or extreme climatic conditions. These systems reflect often rich and sometimes unique agricultural biodiversity, within and between species, but also at ecosystem and landscape level. Founded on ancient agricultural civilizations, some of these systems are linked to important centres of origin and to the diversity of domesticated plant and animal species, the in situ conservation of which is of great importance and global value. The attributes shared by such systems include:

• ecosystem resilience and robustness, developed and adapted to cope with change (human and physical) so as to ensure food and livelihood security and alleviate risk; and

• human management strategies and processes, to allow the maintenance of biodiversity and essential ecosystem services (water recharge and quality, nutrient recycling, soil conservation, pest control etc.) while generating livelihoods and achieving quality of life.

These systems, however, often face great challenges in adapting to rapid environmental and economic change, as well as to new and sometimes inappropriate policy environments, particularly in the context of conflicting land tenure systems, increased climate variability and land degradation, and economic and cultural globalization. To survive and continue evolving, they must also increase their productive capacity and find their comparative advantage and "niche markets", so that they might meet the rising expectations of their members in terms of food security and quality of life.

The traditional rice-fish system is an outstanding example^[9] of GIAHS needing the attention of the global community, given its multiple benefits.

RICE-FISH SYSTEMS: DEFINITION AND EXTENT

Rice is the dominant staple crop of tropical Asia with a long history of domestication. It has a rich diversity of cultivated ecotypes based on three varieties of Oryza sativa: indica, japonica and javanica. There are four basic rice agro-ecosystems, each with particular edaphic conditions: irrigated, upland (terraces), lowland rainfed and flood-prone (very deep water). Fish culture in these systems is concurrent or rotational with rice, and there are four intensities: traditional (capture), low intensity (no fertilization and feed), medium intensity (fertilization but no feed) and high intensity (fertilization and feed). Rice-fish culture enhances both rice and fish production; production is highest at low-medium intensities, although fish diversity is most in traditional and low-intensity systems. Less than 1 percent of rice fields are used for fish culture - probably due to risk aversion among peasant farmers interested in securing domestic consumption in the face of serious information, institutional, infrastructure and policy constraints. Rice-fish farming is innovative and adapts to changes in rice farming. In terms of the global environment, it is important for various reasons:

• it produces greenhouse gases;

• it contains low-moderate biodiversity, with higher levels in traditional and low-intensity systems; and

• it retains floodwaters in shared catchments and river basins.

However, rice-fish systems are highly dependent on husbandry practices for biotope preparation, nutrient and water inputs and replacements, and for managing persistent physical and biotic failures. Rice-fish systems address some biotic failures, such as weed and pest control.

Rice-fish farming systems evolved alongside wet rice cultivation in Southeast Asia over 6 000 years ago (Ruddle, 1982); they are a sustainable form of agriculture (Heckman, 1979; Kurihara, 1989), providing invaluable protein, especially for subsistence farmers managing rainfed systems. Traditional rainfed (lowland and upland), flood-prone (deep water) and irrigated rice agro-ecosystems grow indica and javanica rice varieties in tropical Asia; they lend themselves for fish culture when the whole rice field has a water depth of 0.5 to 3.0 m. However, optimization of rice fields for the production of high-yielding varieties (HYVs) requiring shallow (5 cm) water has required structural changes to fields for fish culture, in the form of deep channels, trenches, drains or sump ponds within these fields or ponds adjacent to them. Rice-fish farming has been recorded in tropical and subtropical Asia over the past 150 years, and its combined production has been propagated most intensely over the past 15 to 20 years, coinciding with international emphasis on food production and security for a rapidly growing human population (Fernando, 1993). Transforming wetlands and rice fields for rice-fish production tends to directly benefit food production and income, as well as farm integration (Lightfoot et al., 1993). A rich variety of direct and mainly indirect beneficial and non-beneficial effects emanate from the interactions between rice and fish (Table 3), with many indirect non-beneficial effects exacerbated by the intensification of rice-fish production.

TABLE 1
Rice ecosystem distribution in agro-ecological zones in Asia

Source: Garrity, Singh and Hossain, 1996.

TABLE 2
Impacts of wetlands transformation for rice and rice-fish culture

Source: Lightfoot et al., 1993 (adapted).

There are basically two types of rice-fish farming systems in Asia: concurrent (or mixed) and rotational. They each have four intensities of production: traditional (or "capture" with wild fish "seed"), and then low, moderate and high (with cultured fish "seed") (dela Cruz et al., 1992). Fish stocking in these systems may range from fewer than 500 to as many as 5 000 fish per ha in high intensity systems, with about 3 000 fish per ha being optimal (dela Cruz et al., 1992; Welcomme and Bartley, 1998). More than 100 fish species are captured or cultured in fresh and brackish water rice fields in Asia in varying combinations (dela Cruz et al., 1992; Ghosh, 1992; Hasan, 1990; Heckman, 1979; Islam, 1983; Newman-Meusch, 1996); they constitute about two-thirds of the fish species used in aquaculture. More fish species are cultured in lowland humid tropical than in temperate or montane rice fields, and in freshwater than in brackish water rice fields. The number off fish species cultured in any rice-fish system depends on the intensity of production, with about a dozen species in capture and low intensity systems and one or two species in high intensity systems.

Intensive culture of rice and fish appears difficult for most peasant farmers producing rainfed rice. The reasons include:

• the uncertainty of annual monsoon fluctuations and fish "seed" supplies;

• the primary objectives of food provision and income generation in developing economies;

• the potential of accidental grazing on rice seedlings by herbivorous fish fingerlings when introduced too early in the cycle; and

• the bioaccumulation of pesticides and heavy metals in fish.

TABLE 3
Direct and indirect effects of interactions in rice-fish systems

^a Non-beneficial effects could be deleterious or competitive.
^b Many competitive effects with rice do not concern fish per se, such as those of auto trophic algae (e.g. green and blue-green) and especially aquatic weeds (e.g. Salvinia, Hydrilla).
^c Fish form an important protein source especially for smallholders and poor farmers.
^d Caused by excessive floods in adjacent wetlands.
^e Caused by leaching of subsurface salts or accidental inflow of tidal waters.
^f By-products of organic decomposition in anaerobic waters.
^g Caused by changes in redox potential.
^h Caused by use of heavy industrial machinery.

GLOBAL IMPORTANCE OF RICE-FISH FARMING SYSTEMS

Rice-fish farming systems are globally important in terms of food production. Furthermore, they appear to be globally important in terms of three global environment issues: climate change, shared waters and biodiversity. Methane is a major greenhouse gas emitted by rice fields, with emission determined by farming practices, plant metabolism and soil properties. Irrigated systems tend to contribute more emissions than do rainfed systems; however, farmers tend to have a poor knowledge of the effects of crop management practices, inputs used, varieties and cultivars grown, and of fisheries integration on methane emissions. As a result, it is not easy either to apply appropriate mitigation measures or to design tradeoffs between mitigation measures and rice and fish production (Ranganathan, Neue and Pingali, 1995). Irrigated rice-fish systems are therefore amajor concern with regard to climate change. While they may be under some form of public or private management, subsidies are required to generate the necessary information for mitigation measures; one possibility is the application of global environmental subsidies from the Global Environment Facility, where national developing economies are unable to allocate them the desired priority. They are also innovative agricultural systems with a variety of local designs adapted to: cultural attributes; appropriate rice and fish species for husbandry; different kinds of water-resource availability, timing and drainage; natural and artificial nutrient inputs for growth; the biological and chemical control of pests and diseases; and edaphic soil and water conditions.

From a biodiversity perspective, rice-fish farming systems embody low-moderate rice genetic diversity due to intense varietal selection, primarily for yields and secondarily for system maintenance and economic viability. There is moderate to high fish species diversity for some protein production of secondary importance, especially in subsistence production systems, and the low (or no) selection of varieties within species. Aquatic biotic diversity is low to moderate, due to the transformation of complex swamp systems into simple agro-ecosystems (Fernando, 1996). Fish species and aquatic biodiversity appear richer in traditional and low-intensity rainfed than in high-intensity irrigated rice-fish systems. The adequacy of this biodiversity for different ecosystem functions - as in agro-ecosystems in general (Main, 1999) - needs careful examination in terms of the global environment in comparison with natural swamp ecosystems.s

TABLE 4
Potential for rice-fish farming in Asia

* Exact figure not available.
Source: Lightfoot et al., 1992.

THREATS AND CHALLENGES TO RICE-FISH FARMING SYSTEMS

Rainfed rice-fish farming systems are threatened by: excessive application of chemicals (particularly pesticides); intensification of rice cultivation for basic staples for a growing human population; intensification of monospecies fish culture; and modern irrigation systems. For example, the rice-fish farming area in China increased from 667 000 ha in 1959 to 985 000 ha in 1986 and 1 532 000 ha in 2000.^[10] However, it decreased from 1 532 000 ha in 2000 to 1 528 000 ha in 2001 and 1 480 000 ha in 2002. The management of rice-fish faming needs more labour and village cooperation than monorice production. A survey in Jiangsu Province showed that half the farmers who adopted rice-fish farming technologies in 2002 preferred to grow single rice or other crops (rather than rice- field farming) in 2003. Some farmers claimed that by digging the same area of rice field as a fish pond, they would make more money than with rice-fish farming. Some farmers who used to practise rice-fish farming reported that they preferred buying fishery products in markets to raising fish in their rice fields. The additional labour required to manage the rice-fish systems costs nearly the same as the value of the fish produced. For fish to reach market size, farmers often need to raise fish in the pond or rice field after the rice is harvested, creating competition for land and labour (increasingly scarce in rural China). However, the food safety, ecological and environment conservation factors are seriously undervalued, as are other ecosystem goods and services in rice-fish farming systems. Considering the multiple livelihood and ecological values listed above, the traditional rice-fish systems are a remarkable model of biodiversity-enhancing agriculture.

POLICIES AND ACTIONS TO REVERSETHE DEGRADATION OF RICE-FISH SYSTEMS

There is potential to build on the heritage of the rice-fish system to balance the shortcomings of the chemical-based agriculture and developing ecosystem approaches to managing wetlands and floodplains. In China, the Philippines and elsewhere in Asia, there has been support and collaboration from local communities, as well as from local and national government for demonstrating these systems as GIAHS.

TABLE 5
Some constraints to rice-fish culture systems in Asia

Source: Dela Cruz et al., 1992 (adapted).

Public care for food safety and ecological conservation is now being addressed through policies on monitoring, ecolabelling (green/organic food programmes) and eco-agriculture. In addition, ecotourism in agricultural areas is also being promoted. There is good potential to integrate the traditional rice-fish culture into those new policy changes.

On the other hand, much has to be done to identify and remove inappropriate policies, institutions and technologies that encourage shifting rice-fish systems to intensive monorice or fish systems.

The incorporation of rice-fish culture in IPM (integrated pest management) programmes and the creation of a favourable environment for aquatic organisms in rice fields offer far more promise than any further refinement of fish culture techniques. In the Philippines, many farmers reported that once they stopped spraying with pesticides, fish returned to their rice fields, reducing the need to stock fingerlings. Since IPM programmes often cover entire villages, the danger of fish poisoning from adjacent fields is minimized (IDRC, 2003). The extension of the system has the potential to reduce the use of POPs (persistent organic pollutants) in agriculture.

Major actions

• Document the changing patterns of the traditional rice-fish system.

• Evaluate the impact of policies, institutions and technologies on farmers' practices in rice-fish systems; and identify those policies, institutions and technologies that encourage specialization of rice or fish production.

• Set up representative demonstration sites and villages through partnership between local communities, government and CSOs (Civil Society Organizations).

• Identify and demonstrate successful adaptations to socio-economic changes, and explore the multiple values of the rice-fish system in food safety, eco-agriculture, ecotourism and ecological conservation.

• Develop networking on conservation and sustainable management of the rice-fish system among communities, local governments and CSOs.

CONCLUSIONS

Traditional and low-intensity rice-fish systems appear interesting in terms of aquatic biodiversity conservation from a global environmental perspective. However, rice-fish systems function within a matrix of farming systems which, in turn, lie within catchment and river basin dynamics. At catchment and river basin level, shared waters become potentially important in terms of quantity and quality to subnational and national jurisdictions. These qualities are determined by biodiversity (as well as other factors). The adequacy of biodiversity at genetic and species level, as well as at farm, catchment and river basin level, needs to be assessed against design goals, adequacy measures and potential risks. Hitherto, a few such integrated assessments of rice fields or rice-fish farming systems have been conducted, for example, in Lake Biwa, Japan, where there is a net outflow of nutrients from rice fields into the lake (M. Nakamura, personal communication). Traditional and low-intensity rice-fish farming systems are important for aquatic biodiversity conservation, at least at catchment and drainage basin level, and they potentially qualify for global environmental subsidies from the Global Environment Facility, especially where private sector interests favour intensive irrigated production systems and the public sector in developing economies is unable to allocate high priority to such systems and their integrated assessments. At meso and macro level, it is necessary to assess the linkages and effects of sector and macro policies, and examine the regulatory, market-based and participatory (institutional) instruments critical for developing new partnerships for ensuring the sustainability and biodiversity conservation of rice-fish systems.

Rice-fish farming can be a low-cost, low-risk option for poor rice farmers in rice-farming countries, including Malawi, Bangladesh, China, India, Indonesia, the Republic of Korea, the Lao People's Democratic Republic, Madagascar, Malaysia, the Philippines, Thailand, Cambodia and Viet Nam (IDRC, 2003).

REFERENCES:

Dela Cruz, C.R., Lightfoot, C., Costa-Pierce, B.A., Carangal, V.R. & Bimbao, M.P. (eds). 1992. Rice-fish research and development in Asia. Manila, Philippines, International Centre for Living Aquatic Resources Management. 457 pp.

Fernando, C.H. 1996. Ecology of rice fields and its bearings on fisheries ands fish culture. In Sena S. de Silva, ed. Perspectives in Asian fisheries: A volume to commemorate the 10th anniversary of the Asian Fisheries Society, p. 217-237. Manila, Philippines, Asian Fisheries Society. 497 pp.

Fernando, C.H. 1993. Rice field ecology and fish culture - an overview. Hydrobiologia, 259: 91-113.

Garrity, D.P., Singh, V.P. & Hossain, M. 1996. Rice ecosystems analysis for research prioritisation. In R.E. Evenson & R.W., eds. Rice research in Asia. Progress and priorities, p. 35-58. 418 pp.

Ghosh,A. 1992. Rice-fish farming in India: past, present and future. In C.R. dela Cruz, C. Lightfoot, B.A. Costa-Pierce, V.R. Carangal & M.P. Bimbao, eds. Rice-fish research and development in Asia. Manila, Philippines, International Center for Living Aquatic Resources Management. 457 pp.

Hasan, M.R. 1990. Aquaculture in Bangladesh. In M. Mohan Joseph, eds. Aquaculture in Asia, p. 105-139. Mangalore, India, Asian Fisheries Society (Indian Branch). 396 pp.

Heckman, C.W. 1979. Rice field ecology in northeastern Thailand. The effect of wet and dry seasons on a cultivated aquatic ecosystem. Monographiae Biologicae, 34. The Hague, Netherlands, Junk Publishers. 228 pp.

IDRC (International Development Research Centre). 2003. Rice-fish culture (available at [email protected]).

Islam, M.A. 1983. A report on aquatic culture in Bangladesh. Fisheries Information Bulletin, Bangladesh, 1(2): BGD/79/015. 28 pp.

Kurihara, Y. 1989. Ecology of some rice fields in Japan as exemplified by some benthic fauna, with notes on management. Internationale Revue der gesamten Hydrobiologie, 74: 507-548.

Lightfoot, C., Bimbao, M.A.P., Dalsgaard, J.P.T. & Pullin, R.S.V. 1993. Aquaculture and sustainability through integrated resources management. Outlook on Agric., 22(3): 143-150.

Lightfoot, C., Costa-Pierce, B.A., Bimbao, M.P. & dela Cruz, C.R. 1992. Introduction to rice-fish research and development in Asia. p. 1-10 In C.R. dela Cruz, C. Lightfoot, B.A. Costa-Pierce, V.R. Carangal & M.P. Bimbao, eds. Rice-fish research and development in Asia. Manila, Philippines, International Center for Living Aquatic Resources Management. 457 pp.

Main, A.R. 1999. How much biodiversity is enough? In E.C. Lefroy, R.J. Hobbs, M.H. O'Connor & J.S. Pate, eds. Agriculture as a mimic of natural ecosystems, current plant science and biotechnology in agriculture, 37, p. 23^2. Dordrecht, Netherlands, Kluwer Academic Publishers.

Newman-Meusch, E. 1996. Participatory assessment of ricefield fisheries in Atsaphangtong District, Savannakhet Province, Lao P.D.R. Auburn, AL, USA, Auburn University. 76 pp. (M.Sc. thesis)

Ranganathan, R., Neue, H.I. & Pingali, P.L. 1995. Global climate change: Role of rice and methane emissions and prospects for mitigation. In S. Peng, K.T Ingram, H.U. Neue & L.H. Zistaa, eds. Climate change and rice, p. 122-135. Berlin, Germany, Springer-Verlag.

Ruddle, K. 1982. Traditional integrated farming systems and rural development: the example of ricefield fisheries in southeast Asia. Agricultural Administration, 10: 1-11.

Welcomme, R.L. & Bartley, D.M. 1998. An evaluation of present techniques for the enhancement of fisheries. In T. Petr, ed. Inland fishery enhancements, p. 1-35. FAO/ODA Expert Consultation on Inland Fishery Enhancement, Dhaka, Bangladesh, 7-11 April 1997. FAO Fisheries Technical Paper No. 374, Rome, Italy.