Climate change threatens Amazonian small farmers

The child of a Brazilian small farmer holds a ripe cacao fruit. Click here for more information.

BLOOMINGTON, Ind. -- A six-year study of Amazonian small farmers and their responses to climate change shows the farmers are vulnerable to natural catastrophes and risky land use practices, say Indiana University Bloomington anthropologists Eduardo Brondizio and Emilio Moran.

The researchers report in Philosophical Transactions of the Royal Society B (now accessible online) that an increase in climate anomalies like El Nino could ultimately drive many small farmers to ruin, forcing them into Brazilian cities that may be ill-equipped to employ, house and feed them.

The researchers found a rapid decay in farmers' memories even of major climate events. For example, more than 50 percent of the farmers surveyed in 2002 did not recall the El Nino-caused drought of 1997 and 1998 -- the worst drought in recent recorded history.

"Because there's so much variability -- even within a three-year period -- most farmers do not seem to maintain a memory of major weather events unless they had some unusual and specific relevance to their lives," said Brondizio, the paper's corresponding author. "Small farmers' collective memory about past climate events is also impacted by the high rate of turnover as new farmers arrive and others leave for cities or new frontiers. It takes time for farmers to learn about a new environment. High rates of family turnover in rural areas further limit the sharing of knowledge and experiences and forms of collective action, such as preventing the spread of accidental fires, to cope with challenging times."

Increasing vulnerability to fire during extended droughts not only impacts the economy, but the forest environment, too.

"Once dry vegetation is affected by fire, the vegetation that comes back is also more fire susceptible, a process well documented in the Amazonian literature," Brondizio said. "Yet the use of fire for land management continues to be widespread in the absence of agricultural support for small farmers."