Measuring quantity in ecosystem markets and ecosystem accounts

The quantity of ecosystem services produced from land cannot be readily measured at the site level needed for participation in ecosystem markets, or at a regional level needed to create ecosystem accounts. This paper applies biological scaling principles to develop a quantity metric in which areas of ecosystem (extent) scale allometrically to ecosystem services (a capacity measure) according to a scaling exponent defined by the fractal dimension of ecosystem vegetation. A key conclusion of this paper is that the quantity of ecosystem services arising from ecosystem degradation and conservation activities cannot be estimated unless information about the space-filling properties of vegetation is observed and included in the quantity measurement methodology. The paper demonstrates how remote sensing techniques can be applied to systematically measure ecosystem extent and fractal dimension. It illustrates the economic efficiency and environmental outcome implications of such a quantity metric through comparison with current quantity estimation methods that assume isometric scaling. The quantity metric proposed has potential applications to ecosystem accounting. It enables information currently reported in land accounts to be combined with information reported in ecosystem condition accounts to create ecosystem stock accounts measured in physical units.