Integrated bioenergy and food production

Rising global energy needs and limited fossil fuel reserves have led to increased use of renewable energies. In Germany, this has entailed massive exploitation of agricultural biomass for biogas generation, associated with unsustainable farming practices. Organic agriculture not only reduces negative environmental impacts, organic farmers were also prime movers in anaerobic digestion (AD) in Germany. This study’s aim was to identify the structure, development, and characteristics of biogas production associated with organic farming systems in order to estimate further development, as well as energetic and associated agronomic potentials. Surveys were conducted among organic farms with AD technology. 144 biogas plants could be included in the analysis. Total installed electrical capacity was 30.8 MWel, accounting for only 0.8% of the total installed electrical capacity in the German biogas sector. Recently, larger plant types (>250 kWel) with increased use of (also purchased) energy crops have emerged. Farmers noticed increases in yields (22% on average) and quality of cash crops in arable farming through integrated biogas production. In conclusion, although the share of AD in organic farming is relatively small it can provide various complementary socio-ecological benefits such as the enhancement of food output through digestate fertilization without additional need for land, while simultaneously reducing greenhouse gas emissions from livestock manures and soils. However, to achieve this eco-functional intensification, AD systems and their management have to be well adapted to farm size and production focus and based primarily on residue biomass.

Local food security initiatives: systemic limitations in Vancouver, Canada

This paper approaches the topic of urban/community gardening not through the lens of urban theory per se but in light of basic farming realities such as growing season and land availability. Food security comprises availability and affordability. In the context of North American and Western European societies, only food affordability normally merits public discourse. In practice, governments have little or no means to change food affordability, in view of prevailing capitalistic free-market structures. In the current wave of popular exuberance, civic politicians and others have promoted the belief that community gardening could be the pathway to produce affordable food. The formidable obstacles to this pursuit include the availability of (low-cost) land within the highly-densified city limit, insufficient ambient temperature and water supply during the growing season and the contemporary structure of society. Overcoming these fundamental hurdles carries significant negative environmental and economic consequences.