Direct Effects of Converting Conventional Cropping Systems to Bioenergy Cropping Systems on Ecosystem Services.

Conventional food, feed, and fiber agricultural landscapes are already being converted to biofuel cropping systems, and this is expected to intensify as demand for bioenergy grows. However, the implications of this conversion for agroecosystem services are not well understood. The objectives of this project were thus to quantify and compare the effects on aboveground primary production, water use, and water quality of converting current conventional cropping systems in the Southeast to emerging biofuel cropping systems, with and without land application of bio-char and evaporated vinasse generated from the conversion of the crop to biofuel. Two large field experiments, one comparing an annual sweet sorghum biofuel cropping system to a cotton-peanut rotation and the other comparing a perennial elephantgrass biofuel cropping system to a perennial bahiagrass pasture system were established in 2012/2013. Passive wick drainage lysimeters were installed below plots (n = 4) of the conventional crop, low-input biofuel crop, biofuel crop with bio-char, biofuel crop with evaporated vinasse, and high-input biofuel crop. Bioenergy cropping systems were quick to establish and data during the 2013 establishing year showed differences in water use and water quality.