October 4, 2007 (Mongabay.com) Growing demand for biodiesel could drive large-scale forest conversion for energy crops, warns a study published in Conservation Biology. With petroleum supplies expected to peak in the next 5-30 years and growing concern over climate change, biodiesel production may expand by 100-fold by 2050, estimates Lian Pin Koh, a researcher from Princeton University. Koh says that much of this expansion could come at the expense of forests, but the degree of which depends on the feedstocks used. Energy crops like palm oil are significantly more productive than more widely used rapeseed — which currently accounts for 84 percent of biodiesel production — but are more likely to be established in carbon-rich and biodiverse ecosystems like the tropical forests of southeast Asia. As such, the environmental trade-off between feedstocks is complex.
Analyzing yields and planting trends for four major biodiesel feedstocks — rapeseed, sunflower seed, oil palm and soybean — and projecting future demand for biodiesel, Koh calculates land requirements for various crops to meet projected demand for biofuels.
“My calculations showed that the scenario of soybean-based biodiesel production to meet future global biodiesel demand would likely result in the highest amount of habitat loss (76.4-114.2 million ha) compared with alternative scenarios of sunflower seed- (56.0-61.1 million ha), rapeseed- (25.9-34.9 million ha), and oil palm-based (0.4-5.4 million ha) biodiesel production,” wrote Koh. “Fulfilling this requirement would entail a substantial worldwide expansion of feedstock cultivation. This could lead to potential land-use conflicts, in particular with the need to preserve the world’s remaining natural habitats.”
To reduce the impact of forecast biodiesel expansion, Koh recommends increasing the area of natural forest under protection, improving oil-yield efficiency of major biodiesel feedstocks, and looking for alternative energy sources beyond biodiesel.
“Future intensification of biodiesel feedstock production in [the tropics], without proper mitigation guidelines, will likely further threaten the high concentrations of globally endemic species in these biodiversity hotspots,” Koh continued. “Given the need to reduce our dependence on fossil fuels and the economic inertia for agricultural expansion in the tropics, there will be no easy solution to the problems caused by intensification of biodiesel feedstock production. There are, however, several key mitigation practices that could help.