The agreement on the Aichi Biodiversity Targets by the Parties of the Convention on Biological Diversity (CBD), the Sustainable Development Goals of the UN Agenda 2030, and the establishment of the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) are encouraging responses to the biodiversity crisis. However, for these international efforts to be successful, our ability to assess biodiversity change must drastically improve. While emerging technologies (such as eDNA) and an increased use of citizen science improve the quantity of and access to biodiversity observations, monitoring efforts are still spatially and temporally fragmented, and taxonomically biased.
In this context, the Group on Earth Observations Biodiversity Observation Network (GEO BON) was established in 2008 with the goal to improve the acquisition, coordination and delivery of biodiversity observations and related services to users including decision-makers and the scientific community . This goal is achieved with the interconnection of two core components: the Essential Biodiversity Variables (EBVs) framework , and a system of coordinated Biodiversity Observation Networks (BONs).
The EBVs can be understood as the level of integration between raw biodiversity observations obtained via in-situ monitoring or remote sensing in space and time, and biodiversity indicators. Those indicators are for instance used to track progress towards international and national targets for biodiversity, and within IPBES assessments.
The BONs, which can be thematic, national, or regional, produce, test and apply tools to deliver EBV-relevant data that can be upscaled and downscaled to support sustainable development and conservation decisions. In particular, regional and thematic BONs connect monitoring efforts across different dimensions and scales of biodiversity while National BONs, which correspond to the operational scale of many monitoring initiatives, are directly oriented to serve the needs of national and sub-national policy-makers.
Here, we will discuss the approach for a coordinated observing system adopted by GEO BON, and review challenges and advances in its implementation, by focusing on its two core components – the EBVs as a standard framework for biodiversity monitoring, and the Biodiversity Observation Networks that support harmonised observation systems - while highlighting their societal relevance.
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