Ecosystem services deriving from sugar kelp cultivation in Skagerrak

Abstract: This Paper will focus on identifying, and look at potential ways of quantifying and valuing ecosystem services surrounding the cultivation of macroalgae. More specifically, the kelp species Saccharina latissima in the sea of Skagerrak at the Seafarm project. This paper is based on a literature review and case studies. Many ecosystem services have been identified and they were divided into the same four categories as in the Millennium Ecosystem Assessment report: provisioning, regulating, supporting and cultural services. To maintain a reasonable scope of this paper the most important ecosystem services were chosen. These ecosystem services were: All the provisioning services, climate and atmospheric regulation, regulation and mitigation of eutrophication and recreation and tourism. All the provisioning services, except reproduction of fish, are related to the amount of harvested kelp. The biomass can be quantified as dry weight (DW) with a relationship between DW and wet weight (WW). The method of quantifying climate and atmospheric regulation is in direct relation to the DW of the biomass. The study shows that the carbon sequestration on a cultivation site can be neglected and carbon stored in kelp used as food, fodder and fertilizer is released back into the atmosphere. Biomass used as biofuel prevents fossil fuel usage and should therefore be quantified. Provisioning ecosystem services are best valuated with the onsite valuation method. The carbon fixation value in climate and atmospheric regulation can be estimated with carbon credits and the oxygen production value can be estimated either with the assumption that it equals the carbon fixation value or with the replacement cost method. The value of mitigation of eutrophication can be estimated with CV and the value of recreation and tourism can also be estimated with CV but also with travel cost.