KdUINO

KdUINO is a low-cost, open-source, Do-It-Yourself (DIY) citizen science project designed to monitor water transparency in aquatic ecosystems. The project enables citizens and researchers to build and deploy their own buoy-based optical instruments to measure the diffuse attenuation coefficient (K_d), a key indicator of underwater light availability, water quality, and ecosystem health.

Developed at the Institute of Marine Sciences (ICM-CSIC), KdUINO originally consists of an Arduino-based system equipped with light sensors placed at different depths in the water column. By measuring how light attenuates with depth, the system provides objective and continuous information on water transparency, which is closely linked to phytoplankton dynamics, suspended matter, and dissolved substances affecting marine and freshwater ecosystems.

Over time, the KdUINO buoy has evolved into a family of instruments, including the KduPRO, which features a modular design, increased robustness, and multispectral capabilities. These instruments measure photosynthetically active radiation (PAR), specific spectral bands (red, green, blue), and multispectral wavelengths in the newer versions.

KdUINO and its derivatives have been deployed in coastal and inland waters, including urban coastal environments and lakes. The project supports citizen participation through workshops, educational activities, and participatory monitoring networks, contributing to increased environmental awareness and improved spatial and temporal coverage of in situ water quality observations.

By generating high-quality in situ data that complement satellite observations, the project supports evidence-based water and marine management and contributes directly to Sustainable Development Goal 6 (Clean Water and Sanitation) by improving freshwater and coastal water quality monitoring, and to Sustainable Development Goal 14 (Life Below Water) by promoting the conservation and sustainable use of oceans, seas, and coastal ecosystems.