ABSTRACT
Biochar has the potential to deliver a variety of sustainability outcomes, including carbon (C) sequestration, improved soil fertility, mitigation of off-site effects from agrochemicals and renewable energy (Lehmann, 2007). However, the benefits of biochar need to be viewed from a systems perspective in order to fully capture the economic benefits and costs, environmental complexity and energy of the technology and to avoid or to minimize unacceptable trade-offs. For example, the clear-felling of tropical rainforests to provide biochar feedstock for C sequestration is clearly unsustainable (Lehmann, 2009). And transportation distances put limits to any biomass use from an economic (Caputo et al, 2005) and ecological point of view (Krotscheck et al, 2000). Biochar systems can be very different from each other. Choices are guided by the availability of biomass, the need for soil improvement or the demand for energy. In addition, biochar
management is often not an alternative to best agricultural or energy management but improves upon advances previously made in practices.
