# Integration of biophysical connectivity in the spatial optimization of coastal ecosystem services

## TL;DR

This paper presents a spatial optimization model that integrates biophysical connectivity to enhance coastal ecosystem service management, demonstrating that small increases in protected areas can significantly improve service provision without relocating existing zones.

## Contribution

It introduces an innovative model combining coastal circulation and ecosystem layers to optimize protected area placement considering larval dispersal and connectivity.

## Key findings

- Increasing no-take areas by 10% maximizes ecosystem services.
- Model effectively incorporates time-varying biophysical connectivity.
- Protected areas are underrepresented in some coastal sections.

## Abstract

Ecological connectivity in coastal oceanic waters is mediated by dispersion of the early life stages of marine organisms and conditions the structure of biological communities and the provision of ecosystem services. Integrated management strategies aimed at ensuring long-term service provision to society do not currently consider the importance of dispersal and larval connectivity. A spatial optimization model is introduced to maximise the potential provision of ecosystem services in coastal areas by accounting for the role of dispersal and larval connectivity. The approach combines a validated coastal circulation model that reproduces realistic patterns of larval transport along the coast, which ultimately conditions the biological connectivity and productivity of an area, with additional spatial layers describing potential ecosystem services. The spatial optimization exercise was tested along the coast of Central Chile, a highly productive area dominated by the Humboldt Current. Results show it is unnecessary to relocate existing management areas, as increasing no-take areas by 10% could maximise ecosystem service provision, while improving the spatial representativeness of protected areas and minimizing social conflicts. The location of protected areas was underrepresented in some sections of the study domain, principally due to the restriction of the model to rocky subtidal habitats. Future model developments should encompass the diversity of coastal ecosystems and human activities to inform integrative spatial management. Nevertheless, the spatial optimization model is innovative not only for its integrated ecosystem perspective, but also because it demonstrates that it is possible to incorporate time-varying biophysical connectivity within the optimization problem, thereby linking the dynamics of exploited populations produced by the spatial management regime.