What Do You Know, Oil Does Cause Land Use Change

In a recent post, I questioned the apparent assumption in the current debate over greenhouse gas emissions from biofuels that petroleum gasoline production does not have an effect on land use change. It turns out there is a well-developed literature on the direct land use change effects of oil exploration in the Amazon and South America.

Chris W. Baynard of the University of North Florida Department of Geology presented a study, “Venezuela’s Heavy Oil Belt: Monitoring Exploration and Production-Related Land Cover Changes,”, at the ESRI 2007 Southeast User Group Conference.

In it he says that most land use land cover change studies on deforestation in tropical regions points to two main drivers, agriculture and logging. The common thread is roads that provide access to these resources and deliver them to market. The same is true for petroleum exploration and production, though, according to Baynard:

Petroleum exploration and production also causes changes to land cover, but some practices create less disturbance than others. [There is a] lack of attention in land use and land cover change literature.”

His study finds that petroleum exploration, pushed by government policies to boost oil production in response to recent high prices (2001-2005), was the primary driver of observed land use change in connection with two large oil development projects in Venezuela’s heavy oil belt. “The extraction of natural resources produces marked impacts on the landscape,” he says.

Carlos F. Mena of the University of North Carolina, Chapel Hill, and Alisson F. Barbieri of the Universidade Federal de Minas Gerais, Brazil, also studied the direct land use change impacts of oil exploration and development in a paper titled “Pressure on the Cuyabeno Wildlife Reserve: Development and Land Use/Cover Change in the Northern Ecuadorian Amazon”:

We find that LULC patterns within and adjacent to the Reserve are influenced by (1) changes in land tenure regimes in newly classified Patrimony Forest, (2) petroleum exploration and production, (3) indigenous communities location, characteristics, and integration to the market economy, and (4) settlement patterns and household characteristics of colonists.”

In 2005, the U.S. imported 449 million barrels of oil from Venezuela (roughly 26% of imports from OPEC countries and 12% of total imports). It also imported 34 million barrels from Brazil, an increase from 19 million in 2004. In 2006, that number jumped to 49 million, according to U.S. Census data.

With global demand rising and supplies declining, evidence suggests that the price of oil will continue to be a driver of exploration and associated land use change in South America. Andy Coghlan of New Scientist recently found that “Unspoilt Amazonian rainforests covering an area almost as large as Texas have been provisionally earmarked for oil and gas exploration.”

Bruce Dale of Michigan State University made reference to this literature in his presentation during a webinar hosted by the North Central Bioeconomy Consortium: “Forest conversion is driven by combined forces: agricultural expansion + timber utilization + road access explain 96% of observed cases but any single factor explains less than 20%.” He correctly observes that so far, the discussion of land use change attributed to biofuels has not been balanced by a comparison to the land use change impacts of petroleum. In terms of regulatory policy being developed by the U.S. EPA, the examination would be relevant.

It’s Carbon Payback Time

A recent study from researchers at the University of Wisconsin takes another look at the “carbon debt” models proposed by Searchinger and Fargione in ScienceXpress earlier this year. Searchinger and Fargione argued that biofuel development in the United States and Europe would lead to the destruction of rainforests and grassland in Brazil and other tropical climates, which would of course release massive amounts of carbon into the atmosphere (See earlier posting).

The new study takes into account some factors that other researchers criticized Fargione and Searchinger for ignoring. Bringing crop yields in the developing world up to the production level in the United States would increase biofuels’ carbon recycling benefits by up to 50 percent, according to the study authors. Further, if biofuels displace future production of oil from tar sands, their climate benefit will increase by another 25 percent. The researchers conclude that “future carbon payback times could be substantially shorter with increases in crop yields, changing petroleum sources and improved biofuel technology.”

Biofuels could have immediate benefits, the study authors conclude, if they are grown on degraded farm land. As another recent study from Stanford University shows, there are nearly 1 billion acres of abandoned farm land around the world. Some of this former agricultural land was once pasture grazed by cattle, and some was cropland that was abandoned for greener fields or because of changing needs. The study’s principle author calculates there is enough land in the United States to supply 9 percent of U.S. transportation energy, using current crop yield data.