Macroalgae sugar kelp and sea squirts for biofuels production investigated in light of impact on ecosystem services

Two out of several potential marine feedstocks for biofuels production that can be cultivated in Sweden are the macroalgae sugar kelp and sea squirts. A new report from the project Marine feedstock based biofuels and ecosystem services, carried out within the f3 and Swedish Energy Agency collaborative research program Renewable transportation fuels and systems, has investigated and summarized the potential impacts of the intensification of marine biomass production for biofuel production on ecosystem services from a Swedish perspective.

Marine feedstocks are depicted as interesting alternatives to more traditional biofuels produced from agricultural crops or forest residues since they require little or no land area and thus do not compete with land-based food production. However, prior to full-scale production, a complete sus­tainability assessment is needed, screening possible impacts of marine-based biofuel production. For this, there is a need to identify the different ecosystem services affected. The newly finished project has aimed to identify and describe the ecosystem services which are affected by the production of marine feedstock-based biofuels in Sweden and to pinpoint appropriate indicators to measure changes for these. This is followed by a quali­tative assessment of the consequences of large scale marine biomass cultivation on provisional, regulating and maintenance, and cultural ecosystem services.

The project, lead by Karin Hansen at IVL, and with participants from IVL and RISE (formerly SP), concludes in its final report that the impact of intensified production of biomass from macroalgae and sea squirts on provisioning ecosystem services is overall positive. In other categories of ecosystem services, the impact is a combination of possible positive and negative effects. For example, microalgae and sea squirts have potential to counteract eutrophication by build­ing up nitrogen and phosphorous in tissue which is removed by harvest. Also, climate change can be mitigated when biofuels from marine biomass replace fossil fuels. On the other hand, large scale aquacultures may lead to low resilience and the dispersal of pests.

All in all, the qualitative and semi-quantitative valuation provided in the report helps to understand the implications of biofuel production from marine feedstocks on ecosystem services.