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7. Managing the resources of the Amazonian Várzea
Christine Padoch |
Background
A diversity of patterns
Diversity, complexity, and change: The case of Santa Rosa
Managing Várzea,
forests
Managing
bananas and diseases in the estuary
Notes
References
The floodplains of the Amazon river and its major white-water tributaries, the várzea, occupy a mere two per cent of the total area of the Amazon basin, but play a role far out of proportion to their relatively small size. Várzeas are often considered the most economically important of all Amazonian lands because of their good soils, their access to transport, and their relatively concentrated human populations. For centuries the floodplains have been very important areas of resource extraction, agriculture, and human settlement. Research indicates that many areas of the várzea were once densely settled by highly organised indigenous peoples. Most of those societies were destroyed in the early years of the European conquest of Amazonia. In contemporary Amazonia, however, most people, both rural and urban, continue to live in or close to the várzea.
The alluvial soils of the várzea, replenished every year by floods, are highly fertile. However, the same annual floods that deposit those rich sediments also make these lands difficult to exploit by modern agricultural methods. Few existing technologies deal adequately with the risks and opportunities the diverse and changeable floodplains present. Today water buffalo ranches increasingly occupy much of the floodplain's fertile lands, particularly along its lower reaches. This extensive land use together with highly intensive and heavily fertilized vegetable production on the outskirts of a few major cities are two conspicuous modern uses. Each has an environmentally and socially questionable present, and an uncertain future. Neither is economically feasible for the great majority of Amazonian farmers.
In areas like the várzea, that are potentially very productive but are unsuitable for exploitation using modern agricultural technologies, it may be most important to look at traditional, smallholder production systems. Attention in Amazon research has turned increasingly to locally developed practices. Researchers have pointed out that indigenous peoples have, over centuries, worked out technologies to exploit and yet conserve resources, including tropical flora, fauna, and soils, and that some aspects of these technologies can be successfully adapted to modern needs and demands. In the Amazon floodplains indigenous peasant and tribal populations use a great variety of agricultural and agroforestry practices that effectively exploit the diverse resources and cropping opportunities the area offers.
In this paper I discuss three examples of locally designed várzea, resource management that are much more than fascinating subjects for scientific study. Each of these systems incorporates much knowledge and experience that is useful in designing appropriate agriculture, agroforestry, and forest management efforts in Amazonia.
To find traditional resource-management patterns and to find the people who best know the area, one should go to the indigenous people, the native Amazonians. Indeed long before the discovery of the Amazon by Europe, the Indians of the várzea, including those of Marajó Island at the mouth of the great river, had built up large settlements, practiced intensive agriculture, and developed sophisticated cultures (Roosevelt 1991). Very few indigenous várzea, peoples, however, survive in identifiable tribal societies. The present inhabitants of várzea, lands and the inheritors and transformers of indigenous traditions are the present-day ribeirinhos (or caboclos) of Brazil and the ribereńos of the Peruvian Amazon.
The ribeirinhos and ribereńos are largely smallholders whose culture is a rich and intricate blend of Amazonian, European, and African traditions. After generations in the várzea, ribeirinhos have developed management patterns and strategies that allow them to make a living in a difficult environment while maintaining the productivity and resilience of várzea, ecosystems.
The várzea, stretches for about three thousand miles from the headwaters to the estuary. The resource-use patterns employed by ribeirinhos/ribereńos along this length are many and it is difficult to generalize adequately about them. Perhaps the most important common characteristics of those local practices are their diversity, complexity, and dynamism. Most ribeirinho smallholders employ an array of resource-management techniques that commonly include several types of farming, agroforestry, forest extraction, hunting, fishing, and occasional wage labour. Many of the strategies and techniques they employ are multi-staged and complex. And despite a persistent outside view of rural folk as tradition-bound and slow to change, várzea, farmers have continually shown that they are eager for change and capable of responding quickly and appropriately to both new problems and opportunities whether environmental, economic, or political in nature.
To some degree the diversity, complexity, and dynamism of resource management is attributable to the environments that várzea, dwellers manage. Often discussed as if it were one kind of environment, we now have come to appreciate that várzea, areas differ greatly. For instance, near the mouth of the Amazon, tides flood vast expanses of várzea, twice daily, but seasonal variations in flood height are not large. This flood regime presents both different opportunities and problems to farmers than do upper Amazon sites where annual floods commonly raise water levels by 10 metres more (Padoch and Pinedo-Vasquez 1991; Denevan 1984).
Great geomorphic and ecological diversity can also be found within a very small area of the várzea, Figure 1 presents an idealized (but not unusual) cross-section of a várzea, area in the upper part of the Amazon basin. You can clearly distinguish four agriculturally important land-forms in this small section. Three of these landforms are located within the floodplain: barreal, or mudflat; restinga, or natural levee; and aguajal, or backswamp dominated by the palm Mauritia flexuosa. The altura (terra firme), or area above the floodplain, is here classified as only one zone, although it does include ecologically different sites and micro-gradients (cf. Denevan 1984). While differences in elevation between these sites may be small, frequently the differences in their potential for agricultural production and the risks they present are very great.
Diversity, complexity, and change: The case of Santa Rosa
While figure 1 is indeed an idealized cross-section, it resembles quite closely the várzea, near Santa Rosa, a community of about 350 ribereńos situated along the edge of the várzea, on the Ucayali River, a large tributary of the Amazon in Peru. Santa Rosa seems to be an unexceptional village and indeed it resembles innumerable other communities scattered along the rivers of the Peruvian Amazon.1 Each one of its residents would identify him or herself as a ribereńo/a; they all speak Spanish, all engage in a combination of agricultural, extractive, and other activities, all are descended from families that have lived along Amazon rivers for many generations, and all are poor. There are, however, very significant differences among the villagers. Residents of Santa Rosa trace their heritage to at least five different ethnic groups (Padoch and de Jong 1990), and they differ greatly in their life experiences. Some have spent much of their lives as urban dwellers and travellers, others have stayed very close to home. Households also vary greatly in just how long they have been part of this particular Amazonian community.
This great diversity hidden under a seeming uniformity also applies to the agricultural and agroforestry techniques used by the people of Santa Rosa. The educated, urban folk of this and many other areas of the tropics would probably dismiss the Santa Rosinos as primitive slash-and-burn farmers; the reality is dramatically different. Exploiting the four different land-forms mentioned above: barreal, restinga, aguajal, and altura, as well as another, the playa, or roughtextured sand bar, which is not pictured on figure 1, the farmers of Santa Rosa have developed 12 distinct ways of farming. These range from the highly risky but very productive farming of rice on barreales where production of 4 metric tons per hectare with no fertilization and minimal labour is not uncommon, to highly diverse, long-term and also profitable swidden-fallow agroforestry on the altura. Seemingly inhospitable environments like the playa are used for short-term plantings of cowpeas (Vigna spp.) and fertile ones like restingas are used for many production types, including monocultures of corn and manioc, as well as large fruit and even timber plantings.
Figure 1 Idealized Cross-section of Floodplain, or várzea, of the Ucayali River (Not to scale)
Not only have Santa Rosinos developed numerous kinds of agriculture, they combine these types into many different patterns. Several years ago we found that the 12 kinds of agriculture available were combined by the 46 individual families in 39 distinct ways. Research showed that there is no one type of agriculture that is used by every household in Santa Rosa and that there is no universally employed strategy. Santa Rosinos do not even agree on whether it is better to diversify resource use, or to specialize in one or two types. Approximately half of Santa Rosa households used four different production types in 1985. A small but significant number - three - however, chose to employ only one production type.
Factors determining which strategy was followed by any household were many and complex. Generally we found that differing access to some kinds of land was important, as were differences in amount and types and the seasonality of labour available to the family. Other important variables were contrasts in access to capital and some capital resources, credit, and opportunities to work beyond the village. Also significant was the family's recent farming history, including losses of crops to floods, as well as general preferences and attitudes. Some farmers were more interested in new crops, techniques, and products, others were less interested in these matters and could be considered more averse to taking risks.
No environment remains static and thus an ability to change is important for any farmer. The Ucayali várzea, however, is characterised by such dramatic seasonal changes that exploiting this environment demands extraordinary flexibility. Any annual flood may change important agricultural land-forms in size, elevation, soil texture, presence of weeds, and spatial relationship with the river. Changes in social factors are no less important. Credit availability, market prices, wage-labour opportunities, and transport facilities change frequently. Families also change in size, health, and in their needs, preferences, and obligations. Any of these factors may affect a household in its decisions on what to plant and where, what fields to continue to manage, and how to alter their management.
Approximately a year after we first studied the households of Santa Rosa, we resurveyed 12 households to see how their strategies had changed. We found then that only three of the families sampled followed the same strategy they had followed the previous year. Nine, or 75 per cent, of the households had adopted a new strategy.
As illustrated by the behaviour of farmers of Santa Rosa, várzea, agriculture is not simple, nor uniform, nor unchanging. Another example from the Peruvian Amazon will serve to show how ribereńo traditions of forest management are also neither uncomplicated nor static.
Near the confluence of two of Peru's greatest rivers, the Amazon and the Napo, is a large area of várzea, where Peruvian ecologist Miguel Pinedo-Vasquez investigated previously unstudied ribereńo techniques of managing important plywood species in várzea, forests. The villagers of Marupá and neighbouring communities of this várzea, are similar in many ways to the farmers of Santa Rosa. They specialize, however, in the management of several types of várzea, forests along the Napo-Amazon floodplain. Capinurales, that is forests dominated by the tree known locally as "capinuri" (Macruira coriaceae), are some of the most economically and ecologically important forests in this area. Residents of the Napo-Amazon floodplain extract several products from capinurales for both domestic use and occasional sale in regional markets. The most important is plywood from the capinuri; other products include: resins, edible fruits, medicinal substances from several species, as well as a variety of other construction materials and firewood.
Capinural forests mainly occupy low natural levees along the Napo-Amazon várzea, floodplain. Much of this floodplain is periodically farmed, and seedlings of capinuri tend to become established quickly in farm fields, as are juveniles in fallows. Although seedlings, juveniles, and adults respond well to natural and human disturbances, dense and economically important stands of capinuri are established after a long process of management and the application of a complex of management techniques.
The management of capinurales takes place at many stages of forest development: in agricultural fields, in young fallows, and in mature capinural forests. At each stage several management techniques are employed. Each of these techniques is composed of multiple, distinct operations.
The entire management process is too complex to be described here;2 I will outline very briefly the main operation of the last 10 of the three stages. At this final stage, when capinurales have become mature forests, two techniques are most commonly used to increase their value: anillado and desangrado. Anillado involves the killing of selected stems of competitor species using girdling of undesirable trees and fire. The technique comprises five activities: selection, marking, removal of understorey vegetation (principally vines), girdling, and burning. The last requires burning a small area of the trunk from which bark was previously removed until the sapwood is affected. The anillado technique usually causes the deselected trees to die rapidly and avoids resprouting from the roots or stem.
Employing the desangrado technique, people remove competitor species, stranglers, and woody climbing vines that may harm valuable trees. The desangrado technique consists of two distinct operations. The first is selection, in which all vines and other plants that are climbing or strangling the trunk or shading valuable trees are selected for removal. The second, girdling, involves the removal of bark, cambium, and sapwood in a ring extending around the woody vine or tree. From the ring fissure, sap, resins, and water are lost. The abundance of resin or sap attracts ants, termites, and other insects that not only eat the sap but also damage any new sprouts. ribereńos forest managers speed the process further by smearing sweet substances on the fissure, tempting even more insects. The resulting infestation controls sprouting of vines and helps kill the competitors.
These two management techniques are applied in managed capinurales on an average of once every six to eight years. By killing vines and selected dominant trees people maintain dense stands of valuable capinuri. The traditional management techniques outlined above apparently succeed in raising the economic value of várzea, forests to local villagers with a minimum of labour and capital input. Pinedo-Vasquez found that management by Marupa villagers neither increased nor decreased the number of trees per area found in the forests. The application of these techniques did, however, result in a significant increase in the commercial volume per hectare of timber in capinurales. The mean commercial volume for areas managed as mature capinurales for 16 years was 89 m3/ha, an increase of 65 per cent over the mean of 54 m3/ha for unmanaged capinurales. This increase in commercial value was produced with the application of very small amounts of labour by Marupá's ribereńo forest managers and virtually no capital inputs. The ideal rotation for the capinurales was just 16 years, far lower than the 50 to 60 year rotations used in most modern commercial management schemes.
The application of traditional management techniques also rather surprisingly resulted in a statistically significant increase in the number of species in capinurales. In contrast to conventional forestry, commercial value was raised but the floral diversity of the forest was not reduced.
Managing bananas and diseases in the estuary
At the other end of the Amazon's várzea, close to where the Amazon flows out to the sea, lies the village of Ipixuna. The residents of this estuarine region have less-direct ties both genetically and culturally to indigenous Amazonians than do most ribereńos of Peru. Some of the present residents are descended from Africans who came into the area as slaves in the early nineteenth century, others are more recent immigrants from Brazil's arid north-east. They share, however, with their Peruvian counterparts a rich tradition of sophisticated resource management of várzea, resources. Like the ribereńos they actively experiment with applying traditional techniques to managing new problems.
Ipixuna and neighbouring communities were until recently major exporters of bananas. Not only did these smallholders supply the urban markets of the state of Amapá with bananas, they also exported to the major Amazonian city of Belém. In the last several years, however, banana production in the region has been almost completely wiped out by Moko disease, called locally febre de banana. The disease, which is common in many banana-producing areas, can be controlled by a concerted and very expensive campaign of destruction of infected plants, repeated disinfection of all tools, and constant inspection of all plantings (Stover and Simmonds 1987). These control measures are not economically feasible for Ipixuna banana producers, and they involve the use of toxic chemicals. Ribeirinhos have instead observed and experimented locally and in the last few years developed an agroforestry system by which they manage the disease although they do not eliminate it.
Ipixuna farmers who are most successful in maintaining adequate production of bananas are those who do the least weeding. In order to produce bananas in an infested area farmers permit weeds and early successional species to fill the spaces in between banana plants while continuing to remove vines and other strangler species. The ribeirinhos who use this pattern, termed the emcapoeirado system, observed that weeding facilitates the spread of Moko disease. Farmers who have significantly reduced the amount of weeding they do in fields that include bananas now produce relatively good crops of banana despite disease attacks; others have lost all or nearly all production. The agroforesters also get an economic return from some of the other species incotporated into their system.
The banana emcapoeirado agroforestry system is but one of many resource management patterns a team of scientists, technicians, and farmers is now studying in the estuarine várzea, in Brazil. Ipixuna is one of the research and training sites of the Amazon Cluster of the PLEC project (Brookfield and Padoch 1994). As part of this international effort my colleagues and I are not only detecting important agricultural systems and monitoring local farmers' fields; we are also designing and implementing relevant experiments and extending knowledge of them to other farmers. In Ipixuna, for instance, Brazilian technicians working with us are evaluating emcapoeirado banana agroforests and contrasting them with others where weeding is more intensive. We are also conducting further experimental studies to understand how the emcapoeirado system of banana production reduces disease infestation and to evaluate its economic viability and its ecological effects.
The banana emcapoeirado agroforestry system is a new adaptation of traditional Amazonian agroforestry and forest management practices.3 Since these systems are based on long traditional patterns, you might ask why these systems are only now being investigated. These systems seem to have been invisible to many of us largely because their developers and practitioners, smallholders like the ribeirinhos, have rarely been credited with sophisticated and valuable knowledge about production and resource management. The systems have perhaps also been invisible because they are confusing to us, they employ principles that many of our advanced, modern systems have discarded. Among these are toleration and even encouragement of biodiversity, principles that many scientists and development experts have only recently come to value. I have presented only a minute fraction of the many traditional resource-management systems that exist in the Amazon várzea, The many scientists of the PLEC Amazon research cluster hope in the next few years to be able to tell you of many more and to be able to show how some of the principles embodied in these systems may be transferred to our modern resource-management schemes, managing them both more sustainably and more productively.
1. This example is described in greater detail in Padoch and de Jong (1992). For descriptions of diversity of production in other villages in the lowland Peruvian Amazon, see works by Hiraoka (1985a,b) and Chibnik (1995).
2. For a detailed discussion of this and other forest-management systems in the Napo-Amazon várzea, see Pinedo-Vasquez (1995) and Pinedo-Vasquez and Padoch (n.d.).
3. Many discussions of Amazonian agroforestry systems, including how Amazonians adapt traditional patterns to modern needs and opportunities, are available. Among these are: Denevan and Padoch (1988); Dufour (1990); Hecht (1982); Irvine (1985); Padoch and de Jong (1987,1989,1995); Padoch et al. (1985); Posey (1984).
Brookfield, H. and C. Padoch. 1994. Appreciating agrodiversity: A look at the dynamism and diversity of indigenous farming practices. Environment 36(5):6-11, 37-43.
Chibnik, M.S. 1995. Risky Rivers: The Economics and Politics of Floodplain Farming in Amazonia. University of Arizona Press, Tucson.
Denevan, W.M. 1984. Ecological heterogeneity and horizontal zonation of agriculture in the Amazon floodplain. In: M. Schmink and C.H. Woods (eds.), Frontier Expansion in Amazonia. University of Florida Press, Gainesville.
Denevan, W.M. and C. Padoch. 1988. Swidden-fallow Agroforestry in the Peruvian Amazon. Advances in Economic Botany 5. New York Botanical Garden, New York.
Dufour, D.L. 1990. Use of tropical rainforests by native Amazonians. Bioscience 40(9):652-59.
Hecht, S.B. 1982. Agroforestry in the Amazon basin: Practice, theory and limits of a promising land use. In: S.B. Hecht (ed.), Amazonia: Agriculture and Land Use Research, 33-71. CIAT. Cali.
Hiraoka, M. 1985a. Mestizo subsistence in riparian Amazonia. National Geographic Research 1:236-246.
Hiraoka, M. 1985b. Changing floodplain livelihood patterns in the Peruvian Amazon. Tsukaba Studies in Human Geography 3:243-275.
Irvine, D. 1985. Succession Management and Resource Distribution in an Amazonian Rainforest. Paper presented at the meeting of the American Anthropological Association, Washington, DC.
Padoch, C., 1. Chota Inuma, J. de Jong and J. Unruh. 1985. Amazonian agroforestry: A market-orientated system in Peru. Agroforestry Systems.
Padoch, C. and W. de Jong. 1987. Traditional agroforestry practices of native and ribereńo farmers in the lowland Peruvian Amazon. In: H.L. Gholz (ed.), Agroforestry: Realities, Possibilities and Potentials. Martinus Nijhoff/Dr W. Junk Publishers, Dordrecht.
Padoch, C. and W. de Jong. 1989. Production and profit in agroforestry: An example from the Peruvian Amazon. In: J. Browder (ed.), Fragile Lands of Latin America. Westview Press, Boulder.
Padoch, C. and W. de Jong. 1990. Santa Rosa: The impact of the minor forest products trade on an Amazonian place and population. In: G.T. Prance and M.J. Balick (eds.), New Directions in the Study of Plants and People. Advances in Economic Botany 8:151-8. New York Botanical Garden, New York.
Padoch, C. and W. de Jong. 1992. Diversity, variation, and changes in ribereńo agriculture. In: K. Redford and C. Padoch (eds.), Conservation of Neotropical Forests: Working from Traditional Resource Use. Columbia University Press, New York.
Padoch, C. and W. de Jong. 1995. Subsistence- and market-oriented agroforestry in the Peruvian Amazon. In: T. Nishizawa and J.I. Uitto (eds.), The Fragile Tropics of Latin America: Sustainable Management of Changing Environments, 226-237. United Nations University Press, Tokyo.
Padoch, C. and M. Pinedo-Vasquez. 1991. Flood-time on the Ucayali. Natural History (May):48-57.
Pinedo-Vasquez, M. 1995. Human Impact on Várzea, Ecosystems in the Napo-Amazon, Peru. Unpublished doctoral dissertation. Yale School of Forestry and Environmental Studies, New Haven.
Posey, D.A. 1984. A preliminary report on diversified management of tropical forest by the Kayapó Indians of the Brazilian Amazon. In: G.T. Prance and J. Kallunki (eds.), Ethnobotany in the Neotropics. Advances in Economic Botany 1:112-26. New York Botanical Garden, New York.
Roosevelt, A.C. 1991. Moundbuilders of the Amazon: Geophysical Archaeology on Marajo Island, Brazil. Academic Press, San Diego.
Stover, R.H. and N.W. Simmonds. 1987. Bananas. Longman Scientific and Technical. Harlow, Essex, UK.