Economic valuation of goods and services

Gas and climate regulation

Gas and climate regulation by photosynthetic fixation of carbon dioxide is of particular socio-economic importance because of climate change. The Isles of Scilly were used as a case study to value this service. Net annual carbon photosynthetic fixation values were estimated by mapping habitats of keystone species of kelp and seagrass. Their productivity (O₂ fixation) was estimated using literature data as well as remote sensing methods. The economic value of this service was then estimated. An adjacent Atlantic Ocean comparison site was used to indicate the relative importance of island biodiversity to this marine service. The Isles of Scilly were approximately twice as productive as the Atlantic Ocean region, fixing 136,495 ton C per year with a mean net present value of €59.109.529, while that of the Atlantic Ocean region was calculated to be €28.641.727.

Disturbance prevention

The role of coastal wetlands as buffer zones against waves and storms has been quantified and valued using two sets of methods: a) a valuation method using coastal householders’ willingness to pay to conserve salt marshes and mudflats, and b) a preventative cost method focusing on the savings made in sea defence construction.

An economic value for the sea-defence role of wetlands was obtained as well as indications that householders preferred natural sea-defences and are willing to pay to conserve them.

Bequest and existence

The value that people place on the existence of European marine biodiversity was assessed across four European sites. The monetary value of marine biodiversity was indirectly assessed by asking respondents their willingness to pay (WTP) to avoid reductions in abundance (10% and 25% of current levels) of various marine taxa including mammals, birds, fish, invertebrates and algae. A total of 1,732 face-to-face interviews were carried out in the Azores, Isles of Scilly, Flamborough Head and Gulf of Gdansk.

There were only small differences in the willingness to pay for different taxa. Mammals and fish were valued more highly than birds, invertebrates or algae. These results show that the general public do value marine biodiversity but, surprisingly, suggest that: charismatic animals do not have a disproportionately strong influence on human preferences for biodiversity conservation.

There are demographic differences in the value placed on marine biodiversity, and MarBEF research is exploring this further.