June 25, 2012
Fernanda Michalski, an ecologist with the University of São Paulo and the Pro-Carnivores Institute, analyzed forest cover trends on properties of various sizes in Alta Floresta in the southern Amazon and conducted interviews with farmers on the presence of wildlife on their holdings. She found that small properties (under 440 ha) tend to have less forest cover. Riparian zones are less likely to be maintained, reducing the connectivity of what forest patches do survive, making it more difficult for wildlife to move. Smaller forest blocks were affected by edge effects, leaving them without the cool, dark, stable conditions of the forest interior that some species require. Accordingly large-bodied mammals, birds, and reptiles are scarce on smallholder properties.
"Degradation caused by deforestation patterns in these small properties have a disproportionally large impact on Amazon forest conservation," she said during a symposium on changing drivers of deforestation organized by mongabay.com.
In contrast to small farms, holdings over 1,000 ha retained 50-60 percent of forest cover. Brazil's Forest Code mandates 80 percent forest cover on private holdings, but the law is poorly enforced. Nevertheless, Michalski's findings suggest large landowners seem to be respecting the law to a degree.
The findings have implications for conservation. With deforestation dropping sharply in the Brazilian Amazon in recent years, a greater proportion is being driven by smallholders, which are more numerous and therefore more difficult to stop. Smallholder clearing may also fall below the threshold of Brazil's near-real time deforestation monitoring system so it's not detected by authorities until well after it happens.
Smallholders often lack land tenure and are therefore sometimes considered "illegal", relegating their product to middlemen and informal markets. Lower revenue can make it more difficult to comply with environmental laws. Arresting deforestation by smallholders is a challenge, according to Simão Jatene, the Governor of Pará, whose administration is working to get them to sign up for the state's mandatory land registry, called the cadastro.
"The challenge is getting smallholders in the cadastro," he told mongabay.com. "We started with big ones that are 80 percent of the problem."
Clearing in the Brazilian Amazon.
Michalski's work hints that focusing conservation efforts exclusively on industrial drivers of deforestation — which account for a growing share of deforestation globally — may miss some of the most damaging practices in the Brazilian Amazon.
"We cannot afford to neglect small properties," said Michalski.
The research is also relevant to the current debate over a proposed revision to Brazil's Forest Code. Under the latest version of the Forest Code passed by President Rousseff, smallholders are exempted from some environmental regulations designed to preserve forests and maintain ecological function, like clear-flowing rivers and stable hillsides.