Fostering the ecosystem-based approach in beach spatial planning and conservation

Abstract

Sandy beaches provide key goods and ecosystem services for human populations around the world. Unfortunately, virtually all sandy beaches are threatened nowadays due to impacts of tourism, urbanization and climate change, which can compromise ecosystem functioning. To successfully protect sandy beach ecosystems in the long term, conservation strategies should be based on sound and integrated scientific knowledge. Nevertheless, sandy beaches are the least studied coastal ecosystem and the information available on their biodiversity and ecosystem processes is insufficient to support ecosystem-based decision-making. Worsening this scenario, almost all studies done so far considered only one component of the sandy beach ecosystem (e.g., intertidal or supralittoral region, benthic or pelagic systems), therefore compromising a full understanding of beach structure and functioning. Additionally, sandy beach management and conservation efforts are mainly focused on physical or socioeconomic aspects, disregarding fundamental ecological characteristics such as functional biodiversity, trophic relationships and ecosystem services provided. We intend to advance in the ecosystem-based approach for beach conservation by combining exploratory field research and complementary methods (e.g., Baited Remote Underwater Videos, stable isotope analysis and habitat suitability modeling) to better understand sandy beach ecosystem structure, functioning, and services. Furthermore, the sampling design will not be limited to a particular group, habitat or process, but will include all sandy beach compartments, from the surf zone to the supralittoral, and will consider benthic and pelagic assemblages and their interactions. This study will be done in 24 non-urbanized beaches encompassing different environmental characteristics, located on the Northern Coast of the state of São Paulo, a 'model area' that contains sandy beaches with distinct morphodynamics on a relatively small spatial scale. This holistic approach will allow the investigation of overlooked topics in sandy beach ecology, the understanding of the main ecological components and processes, including the criteria used to define Ecologically or Biologically Significant Areas (EBSAs, sensu the Convention on Biological Diversity), and the identification of the environmental characteristics that best explain the beach biodiversity and ecosystem services. With such information, we will run habitat suitability models to project the results to all sandy beaches along the whole Northern Coast of São Paulo and elaborate a EBSAs map, which will be available to be incorporated into further beach management discussions. As a final step, the above scientific principles and the leaning process to adapt them to sandy beaches will be then translated into a framework to foster the use of the ecosystem-based approach in beach spatial planning and conservation. (AU)