Land area for establishing biofuel plantations

Abstract

Traditional household fuels involving crop residue and animal dung have severe adverse impacts on soil quality, air quality, water quality, climate and human health. The use of crop residues for fuel and non-use of animal dung for manure have exacerbated the problem of soil and environmental degradation. The attendant decline in soil quality, reduction in agronomic productivity and environment moderation capacity are biophysical processes driven by socio-economic and political forces. The problem is widespread in developing countries where extractive farming practices of mining soil fertility are widely used by resource-poor farmers. Biomass productivity of these degraded soils/wasteland is too low and uneconomic. With rapid increase in population in Asia and Africa, the per capita arable land area is decreasing and is already 0.1 ha in several densely populated countries, and arable land cannot be converted to biofuel plantations. Establishing biofuel plantations ( e.g. , Jatropha, Pongamia) on degraded soils can be a win-win strategy provided that these soils are adequately restored and specific problems (e.g., nutrient and water imbalance, loss of topsoil, shallow rooting depth, drought stress, salinization, compaction, crusting) are alleviated. Another strategy is to adopt practices of land-saving technologies, such as agricultural intensification on prime agricultural lands to improve crop yields, so that surplus land can be converted to biofuel plantations. Production of biofuels can reduce net emissions of greenhouse gases into the atmosphere and advance food security, while achieving energy security, improving environment quality and sequestering carbon in biota and soil. The global potential for soil carbon sequestration is 0.7 to 1.5 Pg C/yr, which can offset 20 to 40 % of the annual increase in atmospheric concentration of CO 2 . Trading carbon credits under the CDM or World Bank funds can provide another source of income for resource-poor farmers. The sustainability of a biofuel production system must be assessed through evaluation of the ecosystem carbon budget, accounting for carbon-based inputs in all on-farm operations and industrial processes.