Biofuel impact on food prices index and land use change

Abstract

Food price and land use data over an extended time period have been examined to identify possible correlations between biofuel production and food price or land use changes. We compared the food price index before and after the biofuel boom in the 2000s to evaluate biofuel's impact on the inflation rate. We found that the U.S. food price inflation rate since 1973 could be divided into three distinct regions. The inflation rate was lowest at 2.6% during 1991–2016, which encompasses the biofuel boom. Among many factors, continuously rising food production per capita was identified as the likely cause of low food price inflation during this period. The US exports of corn have not declined since the 1990s and soybean exports are rising at a steady rate. Among several variables tested as a cause of food price index increase, crude oil price had the highest correlation. We also manually verified the automated land use classification of satellite image covering 664 km2 in three selected areas in the US. We found that 10.90% of non-agricultural land was misclassified as agriculture, whereas only 2.23% of agricultural land was misclassified as non-agricultural. The automated classification showed an 8.53% increase in agricultural land from 2011 to 2015, while the manual classification showed only 0.31% (±1.92%) increase. This result was within the margin of error alluding to no significant land use change. We concluded that automated satellite image land use classification should be verified more rigorously to be used for land use change analysis.