Paving the Amazon: Study helps predict potential deforestation rates along major highways

Photo by CIFOR

BOGOR, Indonesia (22 March, 2012)_ CIFOR scientists are helping to estimate the extent of deforestation that accompanies road paving in the Amazon — even before such roads have been built — which could allow state planners to better assess the costs and benefits of development projects in the region.

“Road paving is a huge shock to any socio-ecological system and it is important to understand the impact of this kind of infrastructural development so that steps can be taken to minimise the deleterious effects,” said Amy Duchelle, a CIFOR scientist based in Brazil, and co-author of Roads as Drivers of Change: Trajectories across the Tri-National Frontier in MAP, the Southwestern Amazon, published last year in the journal Remote Sensing.

While roads can pave the way towards greater economic growth, the swathes of Amazon jungle that are cut down to accommodate them, and the flood of migrants seeking work in newly accessible forest areas are also having extensive impacts on forest ecosystems and the social development of the region, say researchers from the University of Florida, CIFOR, and other organisations studying the impact of such roads in the MAP frontier: Madre de Dios (Peru), Acre (Brazil), and Pando (Bolivia); namely the Inter-Oceanic Highway — a major artery that aims to connect major trading ports in Brazil and Peru.

The three regions are at different stages of infrastructural development. In Acre, the longer presence of the paved highways offers great accessibility to forests, and the study demonstrated that deforestation drops off only after a radius of 45 kilometres away from the road.

The situation is less severe in Madre de Dios, where the process of road paving has only recently been completed. A strong influence of deforestation occurred within 18 kilometres, but this was all along the still unpaved highway; deforestation has likely only increased since paving, as suggested by the study.

Deforestation rates are the lowest in Pando, largely due to a low direct impact by the Inter-Oceanic Highway.

“We can use these trends to predict changes throughout the region, with Acre providing a guide to likely future developments for Madre de Dios, and in time potentially for Pando. While such outcomes are also dependent on a series of socioeconomic and policy factors, highway development in Amazonia is generally a very strong predictor of deforestation.” said Duchelle.

Also, MAP is a relatively remote area and is characterised by a combination of rich natural resources and low incomes, so governments of the three countries are interested in strategies to improve economic development and integration of domestic markets.

Madre de Dios is already experiencing higher population and economic growth as the unpaved Inter-Oceanic Highway was converted to asphalt. In the Peruvian state, road paving has been bolstered by a campaign by the national government and participating construction firms. Former Peruvian president Alejandro Toledo hailed the Inter-Oceanic Highway as a means of increasing access of Peruvian products to markets in Brazil and projected a 1.5% annual increase in GDP.  But it was the Brazilians who funded most of the highway development into Peru.

The economic logic behind the campaign is attractive: trips that take weeks through muddy stretches could be cut to a matter of hours on smooth asphalt; trade would increase and transaction costs could be reduced.

And it seems to have been successful — according to the latest Peruvian census, the lowlands of Madre de Dios have seen rapid population growth, with large numbers migrating from the Andean highlands. Migrants looking for a better life are not the only ones flooding Madre de Dios; big business has followed suit too.

“As soon as people learned that the highway was being paved, there was a lot of land speculation by large landowners who were coming in and acquiring large plots of land as they knew the value of the land would increase tremendously,” said Duchelle.

But letting economics alone determine the fate of the Amazon may result in gross underestimation of the negative environmental and social impacts, warns the study.

Fragmentation of wildlife habitats leading to wildlife mortality and species loss, degradation of stream networks and water quality, the spread of exotic invasive species, and local climate change are all environmental impacts of the growth of the area. Also, social conflicts over land and natural resources are bound to occur when roads threaten to displace communities and their livelihoods.

The viability of maintaining forests managed by small producers, like the Brazil nut concessions located along the Inter-Oceanic Highway in Madre de Dios, have already come under question as there seem to be increasing cases of land invasion in which new migrants, among other actors, harvest timber illegally and convert forests within the concessions for agriculture, said Duchelle. The latter activity results in much higher carbon emissions and has a greater negative impact on biodiversity and the environment.

Road paving is usually part of a broader national and, in the case of the Inter-Oceanic Highway, South American development strategy. This means efforts to divert or stop such projects are unlikely to meet with much success, and deforestation could be a result. But putting into action efforts to minimise the roads’ impacts can have positive results in lowering or stabilising deforestation rates, said Duchelle.

“Such policy interventions can include initiatives to add value to standing forests along roads, such as creating multiple-use protected areas so that people can gain a living from the forests while keeping them standing, and targeting REDD+ initiatives at such areas of high additionality.”

Duchelle cited the example of the Chico Mendes Extractive Reserve, which is a protected area located within the deforestation zone of the Inter-Oceanic Highway, and which shows more forest cover than surrounding areas. The Reserve was named after Mendes, a Brazilian rubber tapper murdered by ranchers opposed to his conservation efforts in the Amazon. She also explained how sub-national REDD+ initiatives are being targeted at forests and communities along highways in the region, including the Inter-Oceanic Highway in Madre de Dios, and along another highway in Acre that is being paved to the more remote northwestern part of the state.

“Many of these efforts have to happen while the roads are being built,” said Duchelle. While we can say that roads will have big effects in any deforestation model, policy decisions can truly minimise these effects.”

Studies such as the one discussed here may be useful for informing such policy processes.