Sir

After 40 years of government-induced settlement of the Brazilian Amazon, the core of this region has experienced surprisingly little deforestation. The agriculture and ranching that cause deforestation depend upon reliable roads, which are concentrated along the eastern and southern flanks of Amazonia (Fig. 1). This 'passive protection' of central Amazonia may soon be lost, however, unless the proposed paving of roads through the core of the region is reassessed.

Figure 1: Infrastructure investments described in the Avança Brasil programme.
figure 1

The current frontier is indicated by deforestation (red).

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The Brazilian government has revised its directives for Amazonian development as part of its Avança Brasil (Forward Brazil) plan. This is an ambitious programme for development in Brazilian Amazonia, involving infrastructure investments of US$45 billion over the next eight years.

The plan emphasizes road paving, river channelling, port improvements and expansion of energy production (Fig. 1). If implemented, it will add 6,245 km of paved highways to the region's road network, including the Santarém-Cuiabá and Humaitá-Manaus highways, which cut through the core of the region (Fig 1 A, B)1. Paving these highways is justified by the transport cost savings that would accrue to soy farmers in north-central Brazil, but would have substantial attendant environmental costs, such as increased deforestation, logging and forest fires. Establishing these 'export corridors' would lead to further dilution of the state's institutional capacity and of the limited resources available for social development within existing Amazon frontiers2,3.

If the historical relationship between roads and forest loss continues, then the planned road paving will cause between 120,000 and 270,000 km2 of additional deforestation, and further forest impoverishment through logging and understorey fire over the next two or three decades2,3. Combined with deforestation occurring within the existing frontier, the deforested portion of the Brazilian Amazon could increase from 14% (550,000 km2) today to a third of the total area over the next 20–30 years. This would release 6 billion–11 billion tonnes of carbon into the atmosphere from forest clear-cutting alone3. The roads would come within 50 km of 22 conservation areas and 89 indigenous lands3.

If Amazonia is to avoid the 'business-as-usual' experience of frontier expansion that has consumed most of the world's forests, Brazil should adopt an alternative development pathway in which investments are designed to strengthen the economic vigour and institutional capacity of existing settlement regions before roads are paved deeper into the forest.

Investments could be concentrated along the Transamazon, Belém-Brasília, PA-150 and BR-364 highways (Fig. 1 C–F, respectively), where ageing frontiers are languishing in the wake of timber depletion, gold mining and land speculation4. These investments include the improvement of local road networks, marketing facilities, technical support, schools and health systems. Financial incentives are needed for sustainable forest management and permanent agriculture initiatives. Institutions must be strengthened to streamline the land titling process, and to implement Brazil's very ambitious environmental legislation through monitoring and control of predatory land-use activities. This approach would stimulate regional development, while preserving the world's largest passive forest reserve.