Ecosystem functions at the island scale: a contribution to the design of ecological structure

The concept of ecological structure (ESt), as implemented through spatial planning, has been recently used to protect ecosystem functions (EFs) and services and their contribution to human well-being. This study intends to provide an exploratory analysis to operationalize the inclusion of EFs in the design of ESt in territories lacking detailed individual studies on EFs. The objective is to advance this concept in small island ecosystems and use Pico Island (Portugal) as case study. The proposed methodology identifies EFs contributing to the objectives of ESt. It uses (i) geographic data available from studies on individual EFs and (ii) definition of territorial units (TUs), based on biophysical features, used as cartographic units to assign and map remaining EFs. A total of 15 EFs were selected among three main categories: natural regulation (10), support (3) and cultural (2) functions. Geographic data are available for carbon storage and groundwater recharge. To assign the remaining EFs, a total of 86 TUs were defined. The performed analysis suggested that the use of EFs, along with multi-criteria decision-making techniques, could successfully contribute to define ESt and integrate it into spatial planning on Pico Island and other small islands systems.