Ryan Blanchard

Anticipating potential biodiversity conflicts for future biofuel crops in South Africa: incorporating spatial filters with species distribution models

Liquid biofuel production will likely have its greatest impact through the large‐scale changes in land use that will be required to meet the production of this energy source. In this study, we develop a framework which integrates species distribution models, land cover, land capability and various biodiversity conservation data to identify natural areas with (i) a potentially high risk of transformation for biofuel production and (ii) potential impact to biodiversity conservation areas. The framework was tested in the Eastern Cape of South Africa, a region which has been earmarked for the cultivation of biofuels. We expressly highlight the importance of biodiversity conservation data that enhance the protected area network to limit potential losses by comparing the overlap of areas likely to become cultivated with (i) protected areas; (ii) biodiversity hot spots not currently protected; and (iii) ‘ecological corridors’ (areas deemed important for the migration of species and linkages between important biodiversity areas). Results indicate that the introduction of spatial filters reduced available land from 54% to 45%. Including all biodiversity scenarios reduced available land to 15% of the Eastern Cape should avoiding conflict with biodiversity conservation areas be prioritized. The assumption that agriculturally marginal land offers a unique opportunity to be converted to biofuel crops does not consider the biodiversity value attached to these areas. We highlight that decisions relating to large‐scale transformation and changes in land cover need to take account of broader ecological processes. Determining the spatial extent of threats to biodiversity facilitates the analysis of spatial conflict. This article demonstrates a proactive approach for anticipating likely habitat transformation and provides an objective means of mitigating potential conflict with existing land use and biodiversity.

Bioenergy potential from invasive alien plant biomass in South Africa

South Africas natural resources are severely impacted by invasive alien plants (invasive alien plants) that cover about 18.2 million ha with a mean density of 8.2%. The distribution of these plant invasions, together with information of biomass yields of biomass, were used to estimate the total accessible woody biomass of invasive alien trees to be 167 million tonnes (dry). The biomass can be used to produce wood-based fuels (wood pellets, torrefied wood chips and pellets, charcoal, or bio-syncrude) for co-firing with coal at power stations without major capital investments or modifications. If approximately half of the total invasive alien plant biomass is used for co-firing over a twenty-five year period, Eskoms annual coal demand will be reduced by almost 3% and 964 MW of biomass-to-electricity will be added to the national electricity supply mix. These bioenergy opportunities often struggle to be financially feasible due to the significant costs to access, harvest, store and transport the widely distributed and varied invasive alien plant biomass and will likely require coinvestment through public-private partnerships. Linking the governments land user incentive programme with an private sector activity, such as biomass to electricity, has the added benefits of providing jobs in the public works sector, stimulating rural development, reducing carbon emissions, increasing water availability, and helping to steer South Africa towards a Green economy and a more sustainable development path.

Biogas for mobility: Feasibility of generating biogas to fuel City of Johannesburg buses

Biogas is a renewable fuel that can be used for electrical power, heating/cooling, and as a transport fuel. This study assessed the feasibility of using biogas to fuel buses in the city of Johannesburg, South Africa. The use of biogas for transportation delivers more financial value-adding compared to using biogas for electricity-R235/GJ for transport fuel and R111/GJ for electricity. The cultivation of land and use of energy crops as feedstock for biogas production will require at least seven hectares per bus; which will place additional demands on the citys scarce land resources and create potential conflicts with food production. Biodegradable wastes are alternative feedstock for biogas production that avoids these impacts, while diverting organic waste from landfill. Using size-location modelling, we identified the optimal locations for two large (>2000Nm3/h) biogas facilities that use the organic fraction of municipal solid waste as feedstock to produce upgraded biogas (bio-methane) that can fuel up to six-hundred city buses. Benefits of using biogas for city buses include reducing carbon emissions, improving local air quality, increasing transportation efficiency, delivering new opportunities for transit orientated development and facilitating the transition to a Green economy.