“The study finds that biofuels can be instrumental in bringing an agricultural renaissance that revitalises land use and livelihoods in rural areas. Price signals to small-scale farmers could significantly increase both yields and incomes, securing real, long-term poverty reduction in countries that have a high dependence on agricultural commodities. Large-scale biofuels cultivation could also provide benefits in the form of employment, skills development and secondary industry.
However, these possibilities depend on security of land tenure. Where competing resource claims exist among local resource users, governments and incoming biofuel producers, and where appropriate conditions are not in place, the rapid spread of commercial biofuel production may result – and is resulting – in poorer groups losing access to the land on which they depend. In these contexts, the spread of commercial biofuel crop cultivation can have major negative effects on local food security and on the economic, social and cultural dimensions of land use.”
http://pubs.iied.org/pdfs/12551IIED.pdf

These might also be of interest:
http://e360.yale.edu/feature/wood_pellets_green_energy_or_new_source_of_co2_emissio
ns/2840/
http://www.nrdc.org/energy/files/southeast-biomass-exports-report.pdf

My own conclusion is that we shouldn’t let our our enthusiasm for alternatives to fossil fuels blind us to their possible negative effects. This concern seems to be especially valid for biofuels.