The objective of the ELADE project is to (1) characterize the enrichment pathways in Poé lagoon, likely to induce algal blooms in this area, and define their diversity and dynamics, (2) propose decision support tools that can anticipate or control these phenomena. The field campaigns took place from 2019 to 2020, including: missions to collect algae and monitor their recovery, sampling of groundwater, surface water, and lagoon water, as well as missions for lagoon instrumentation (including current meters).

This project will identify and validate relevant indicators for monitoring the risk of eutrophication, which are currently lacking for shallow New Caledonian lagoons exposed to terrigenous inputs. These objectives complement the PRESENCE project (Ifremer, New Caledonian Collectivities 2017-2021 framework agreement).

ELADE is articulated in 6 complementary tasks.

- Task 1: led by BRGM is interested in the functioning of the water table, at the level of the Gulf of Déva;

- Task 2: led by Ifremer, is interested in the hydrodynamic functioning of the lagoon, taking into account the watercourses that can influence it;

- Task 3: led by Ifremer, is interested in nutrient inputs into the lagoon;

- Task 4: conducted jointly by IRD and Ifremer; focuses on the diversity and dynamics of green algae;

- Task 5: led by Ifremer, integrates elements from the previous tasks to meet the objectives of the study;

- Task 6: aims to bank the data acquired during the project to facilitate their use and integration in future studies.