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Driving
forces and the mythical hamburger connection
Pasture
development in the uplands
Pasture
restoration
Savannas
Pasture development in Amazonia is often mired in controversy. From the social standpoint, ranches provide minimal employment and in some cases have led to conflicts over land rights (Schmink and Wood 1992). Alarms have sounded about creating biological deserts in artificial pastures. Furthermore, pastures cleared in forest are often deemed unsustainable (Fearnside 1989b). Three prevailing myths about cattle-raising in Amazonia need to be put to rest: (1) that ranching is the domain of large landholders; (2) that cattle-raising is chiefly an artefact of fiscal incentives; and (3) that pasture formation in Amazonia is the principal cause of forest destruction.
Much of the heated debate about pastures in the region stems from the relatively recent push to open up artificial pastures in mature forest. Traditional cattle-raising on natural flood-plain meadows and on patches of savanna poses fewer ecological and cultural hazards than forest-clearing on the uplands. In the case of small- and medium-scale operators, cattle pastures are formed only after one or more cropping cycles with annual crops. Instead of returning the land to second growth, some farmers prefer to form pasture (Hébette 1991). Even some of the larger ranchers often sow rice and/or maize with pasture grasses in order to recoup some of their costs. It is thus difficult to assign with any degree of accuracy the proportion of deforestation due to cattle-raising. Whether on flood plains, savanna, or artificial pasture in upland areas, cattle have become an integral part of the regional economy. In cleared areas of Amazonia, cattle-raising is usually the dominant land-use system.
In 1985, cattle accounted for one-quarter of the agricultural production of the states of Pará, and Rondônia. In the latter state, the cattle herd had grown from 7,800 head in 1970 to some 2 million by 1991 (Falesi and Osaqui 1992). SUDAM (Superintendência do Desenvolvimento da Amazonia), a regional development agency, facilitated the investment of US$880 million in cattle projects in the Brazilian Amazon between 1966 and 1978 (Dwyer 1990: 81).
Cattle-raising is an attractive proposition in frontier areas of Latin America, including the Amazon? for a number of reasons. First, cattle are a highly liquid investment. Second, cattle can be easily walked long distances to market when roads are in poor condition. Third, sales can be delayed without major losses in most cases. Fourth, the marginal cost of establishing pasture after cropping is low for smallholders. Fifth, ranching is a low-risk operation compared with crop farming (Seré and Jarvis 1992).
Small farmers often maintain a few cattle for milk, for a quick sale when a financial crisis looms, and to provide manure for crops. For many small operators, cattle are a more secure and familiar investment than banks, whose interest rates do not always accompany inflation (Hecht 1992). Cattle-raising thus transcends farm size.
Cattle's impressive role in the regional economy is not simply an artefact of fiscal policy incentives. After it became apparent that SUDAM incentives for cattle pasture were being used primarily for land speculation and timber extraction, the federal government withdrew subsidies for pasture development in forested areas of Amazonia. This was expected to curtail pasture development in the region (Collins 1990: 42).
Even without fiscal incentives, though, cattle-raising remains the predominant land use in pioneer areas of Amazonia (Hecht 1992; Homma et al. 1992b). In Acre, for example, pasture is by far the most common vegetation in cleared areas, occupying 55 per cent of such areas in 1987 (FUNTAC 1990b). In the vicinity of Parauapebas, at the base of the Carajás range in southern Pará, cattle pasture with varying degrees of invasion by weeds accounts for about 90 per cent of the cleared land after 10 years of settlement. Settlers from the North-east region and central Brazil occupy homesteads in the 50 ha range and prefer to sow guinea grass (Panicum maximum) after a crop of rice because it is easier to manage. Small- to medium-scale ranches also dominate the landscape around Marabá, a Brazil nut town that has grown rapidly since the advent of several pioneer roads in the 1970s, and in colonization areas of Rondônia. (fig. 7.1). The trend towards cattle-raising remains strong in western Amazonia and many other parts of the American tropics (Hiraoka 1980a).
A variety of cultural and socio-economic forces have propelled cattleraising to one of the leading economic activities in both pioneer areas and longsettled parts of Amazonia. Cattle represent capital assets that can be readily sold when a crisis or opportunity arises. Cattle-raising is not labour intensive, an important consideration in rural Amazonia where the paucity of available workers is a perennial complaint. Small farmers are especially attracted to cattle-raising as one of their major land-use options because they have fewer resources to hire labour (Homma et al. 1992b).
Milk production is another powerful force behind the sowing of grasses in Amazonia. Small farmers, in particular, are keen to maintain a few cows to provide milk for the family. Small and medium-sized ranches, such as in the vicinity of Marabá, provide milk for the market as well. Large-scale operators tend to concentrate on beef production. Marabá, now has two dairy plants, which send milk in plastic bags to Belém In nearby Morada Nova along the PA 70 highway, Leite Carajás works with some 400 farmers and small-scale ranchers. Leite Carajás has a capacity of 35,000 litres/day, and sends milk to Marabá, and cheese to Belém Marabá, has emerged as one of the more important dairying centres in Pará, within the past 10-15 years. The growth of the dairy industry around a town formerly linked mainly with the Brazil nut trade is largely a result of improved road transportation to Belém along the PA 150, which opened in 1978, and of Maraba's spectacular growth from around 4,000 inhabitants in 1970 to about 150,000 in 1992.
An appreciation of beef and a predilection for cattle grazing are rooted in Iberian culture. Cattle were imported to Belém in 1644, and the first ranch was established on nearby Marajó Island in 1692 (Le Cointe 1918: 9). Cattle have thus been part of the cultural landscape of the Amazon basin for centuries.
Ranching is more prestigious than growing crops, and many pioneer settlers aspire to phase out, or reduce, their involvement in the arduous task of growing crops (Smith 1982). Cattle are easily herded to market, whereas crops may spoil in the field because transportation cannot be arranged. The precarious condition of roads and bridges after the rainy season in many parts of Amazonia results in considerable post-harvest losses.
Amazonia has been implicated in the "hamburger connection," which attributes tropical deforestation to the appetite for fast food in North America, particularly the United States (Hall 1989; Myers 1980a; Roddick 1991: 197). Yet the region has never been a significant exporter of beef. In 1982, the Brazilian Amazon supplied 0.0007 per cent of US beef consumption (Browder 1988); since then, the region has hardly been able to meet domestic demand for meat. Brazil exports mostly processed beef, such as corn beef and sausage. Amazonia is a net importer of beef in most years, and foot-andmouth disease prevents the region from becoming a significant exporter of chilled beef to foreign markets (Hecht and Cockburn 1989: 98).
The "hamburger connection" asserts that consumers in North America are responsible for converting substantial areas of tropical forest to pasture in Latin America (Harris 1983). Rain forests in Central America were even projected to disappear by 1990, in part because of the growing appetite for fast food in the United States and Canada (Lavelle 1987; Myers 1980b). Deforestation in Central America stirred most of the controversy over the "hamburger connection," which in turn spurred protests against Burger King and prompted denials from McDonalds that foreign beef was used in their hamburgers (Nations and Komer 1987).
At its heyday in the 1970s, the "hamburger connection" was tenuous even in Central America. Beef exports from Central America peaked in 1979 at 162,000 metric tons and declined to some 61,000 tons by 1985 (Myers and Tucker 1987). Beef exports from Central America, never significant on a global scale, have now essentially dried up because of increased domestic consumption. It is clearly time to put the "hamburger connection" on the backburner.
Domestic, rather than international, demand for beef is one of the main driving forces behind cattle production in Amazonia. Rapid urban growth in Amazonia is creating an ever-greater demand for meat and dairy products. Domestic beef markets therefore spur forest-clearing in Amazonia. In the short term at least, it often makes economic sense to convert forest to pasture. The liveweight price of cattle in Amazonia fluctuates, as with most commodities, but fattening steers remains one of the most profitable agricultural activities in Amazonia.
By 2030, 80 per cent of the population of the Brazilian Amazon is expected to live in urban areas (Vera and Alves 1985). If the projected demand for beef in Brazil of 5.6 million tons by 2000 is to be met, production will have to double (Montoro Filho, Comune, and Melo 1989). Demand for milk in Brazil is also expected to double in the 1990s. By 2000, beef consumption in Brazil is expected to exceed production by 44,000 tons (CIAT 1991: 67). As incomes rise in Manaus, beef consumption increases at a faster rate than consumption of other sources of animal protein, such as fish (Amoroso 1981). A similar pattern probably prevails in other Brazilian cities.
The need to intensify production
Given the growing demand for beef and dairy products in Amazonia, boosting the productivity of cattle and water buffalo herds becomes imperative. Particular attention is needed to raising the productivity of existing pastures and range land, while minimizing environmental damage and adverse social impacts. The demand for beef and dairy products can be met, at least for the foreseeable future, by improving production on pastures already established in cleared forest and on natural grasslands. By boosting the output of cattle and milk from existing pasture and grassland, pressure can be relieved on remaining forest areas.
Some might argue that devising low-cost technologies to improve the economic viability of cattle-raising in Amazonia will only exacerbate forestclearing. Precisely the opposite is likely to occur. Intensification of agricultural and livestock production alone will not "save" wilderness, but it provides some manoeuvring room. At least a farmer or rancher has more options for raising crops, or leaving forest alone, if output is increased on areas already in production.
The big push to open up new cattle pastures in Amazonia started in the late 1960s and was targeted at forest areas. Attracted by generous fiscal incentives promulgated in 1967, corporations started investing up to half their taxes in development projects in Amazonia. A "grass rush" of major proportions quickly ensued in eastern and southern Amazonia (Sternberg 1973). Some 15 million ha of forest, mostly in southern Pará, and northern Mato Grosso, have been felled and planted to a variety of grasses since the mid-1960s.
First-generation grasses on recently formed pastures in the uplands were mainly guinea grass (Panicum maximum), Brachiaria (Brachiaria decumbens), and, in drier areas, jaraguá (Hyparrhenia rufa). Within about five years, however, weeds, resprouting trees, and compacted soils depressed the productivity of many of these new pastures. The carrying capacity of neglected pastures often fell below 1 head/ha, compared with 1.5-2 head/ha on newer, bettermanaged pastures. At Fazenda Boi Branco near Paragominas, Pará, for example, the carrying capacity of a 12-year-old Panicum maximum pasture had dropped to 0.5 head/ha until it was restored with Brachiaria brizantha cv. Marandu in 1990.
Table 7.1 Pasture grass turnover in Amazonia in response to weed and pest problems, among other factors
| First
generation (1965-1975) |
Second
generation (1975-1982) |
Third
generation (1983-Present) |
| Panicum
maximum Brachiaria decumbens Hyparrkenia rufa |
Brachiaria humidicola | Brachiaria
brizantha Andropogon gayanus |
Note: All species are still cultivated in the Brazilian Amazon, but first-generation species are now much less common.
Pests and germ-plasm turnover
Spittlebugs (Deios spp.) have triggered a turnover of grasses in artificial pastures in Amazonia. In the mid-1970s, spittlebug attacks, especially by Deios incomplete, exacerbated weed problems in many Brachiaria (Brachiaria decumbens) pastures (fig. 7.2). Known as cigarrinha in Brazil, the small bugs can spread and multiply quickly. Spittlebugs feed on the grass sap, thereby withering the pasture and allowing weeds to proliferate (Penny and Arias 1982: 65).
Spittlebugs forced ranchers to seek alternative grasses in order to recoup lost productivity. The stage was set for a second generation of pasture grasses (table 7.1). In 1976, many ranchers turned to quicuio da Amazonia (Brachiaria humidicola), a fast-growing grass with moderate resistance to pests. An African grass, as are all introduced pasture grasses in Amazonia, quicuio has also been widely used for erosion control along roads, railways, and electrical transmission lines. By 1982, however, some pastures of B. humidicola were being severely attacked by Spittlebugs in the Paragominas area, possibly because of the pronounced dry season, which weakens the plants.
In wetter areas of Amazonia, such as near Belém Brachiaria humidicola and to a lesser extent B. decumbens still resist spittlebugs. Belém and much of the adjacent Bragantina zone receive around 3,000 mm of rain annually, compared with about 1,700 mm in the Paragominas and Manaus areas where spittlebugs have wreaked havoc. At Fazenda Itaqui, 54 km east of Belém on the BR 316 highway, a 20-year-old pasture of B. humidicola is still productive because it is fenced, thereby allowing rotation of cattle-grazing, and is weeded and fertilized periodically (fig. 7.3). Also in the Bragantina zone, a 20-year-old pasture of B. decumbens cleared from second growth is still grazed because the heavy rainfall depresses spittlebug populations and because the pasture is fenced and weeded; this pasture, located at Fazenda São Judas Tadeu, 19 km from São Miguel do Guama, has never been fertilized.
Many ranchers have been planting braquiarao (Brachiaria brizantha cv. Marandu) since 1983, in part to escape problems of spittle-bugs. Also known as brizantão, B. brizantha is more vigorous than B. humidicola, provides better ground cover to suppress weeds, and currently resists spittlebugs. Although more demanding of soil nutrients and physical conditions than first-cycle Brachiaria species, brizantão is rapidly replacing first- and second-generation pasture grasses in many parts of the Brazilian Amazon (fig. 7.4). Third-generation pastures are generally under more intensive management.
Weeds and degraded pastures
Close to half of the artificial pastures in Amazonia are degraded (Hecht 1985; Serrão and Toledo 1988). Degradation generally refers to weed infestation, which in turn can be facilitated by pests or deteriorating soil conditions. The proliferation of weeds can be a symptom of soil exhaustion or compaction, but not always. Pastures with numerous termite mounds appear to be in poor condition. The infestation of volunteer plants can thus be a consequence of soil depletion and compaction, overgrazing, underutilization, or insufficient weeding. Weed infestation is a sure sign of poor pasture management.
Weeds originate from seeds dropped by birds, other animals, and the wind, and from imported seed. Stump resprouting in relatively new pastures can also quickly shade out grass. Weeds can take over relatively fertile pasture if they are not checked. Overstocking or understocking can also favour the emergence of unwanted plants in pastures. Manual clearing is the most common method of controlling weeds on an annual basis; herbicides are generally too expensive.
Dozens of unwanted plants arise in pastures in Amazonia. The composition of weedy communities varies markedly within an area and between different parts of the Amazon. A few weeds stand out as being especially troublesome. In the Manaus area, vassoura de botão (Borreria sp.) is a pernicious rubiaceous weed, while around Paragominas, matapasto (Cassia spp.), milkweed (Asclepias spp.), and species of Verbena infest some pastures. Along the PA 256 road linking Paragominas and Tomé-Açu, lacre (Vismia guianensis) forms virtually pure stands in some degraded pastures. In the Marabá, area, babaçu palm (Attalea speciosa) or assar-peixe (Vernonia sp.) typically dominate poorly managed pastures. Some pasture weeds are an important source of food for butterflies and bees, which may in turn provide pollination services to other plants, including economic ones. The complex interactions of weed populations and pasture management warrant further study.
Pastures sown with various species of Brachiaria are prone to infestation with several grass weeds. Seed from the Brachiaria grasses is collected from the ground, whereas seed from Panicum maximum is gathered from the mature spikes, thus reducing the chances of weed contamination (Nepstad, Uhl, and Serrão 1991). Pastures of Brachiaria can be established by cuttings, but this procedure is labour intensive and can pose problems for ranchers, even though the minimum wage is only US$60/month. Furthermore, workers are often scarce in pioneer areas. At least one vigorous pasture weed, capim navalha (Paspalum virgatum), is thought to have entered Amazonia with Brachiaria planting seed (M. Simao, pers. comm.). Although P. virgatum is also a grass, it is much less palatable to cattle. Sapé (Imperata brasiliensis), the ecological equivalent of the notorious alang-alang grass (Imperata cylindrica) of South-East Asia, may have been introduced to some parts of Amazonia after 1970 in seed of Brachiaria humidicola. Both Paspalum virgatum and lmperata hrasiliensis are indigenous to Amazonia; a striking feature of weeds in both pastures and fields of Amazonia is that most are native to lowland South America.
Some ranchers are aware that not all invading or resprouting plants in pastures are a nuisance. Fazenda Boi Branco near Paragominas is allowing some forest trees to resprout in pastures if they have timber value. Some leguminous pasture "weeds," such as Mimosa sensitiva and matapasto, enrich the soil with nitrogen. Still other volunteer plants in pastures are highly nutritious and are eaten by cattle (Camarão et al. 1990).