FERRO continues to make significant progress towards its objectives, delivering innovative solutions for lake restoration and management. One of the project's key achievements is the development of an approach for identifying and classifying nutrient residue hotspots in both shallow and deep lakes, supporting more targeted and effective restoration efforts. 

Background: Why do we need targeted identification of phosphorus-releasing sediments?

Internal nutrient loading from residue is a major cause of eutrophication. This happens particularly in many shallow lakes, rich in nutrient systems and deeper accumulation zones. 

Currently, only a small number of sediment cores are representing entire lakes in assessment approaches. This can lead to significant uncertain and inaccurate estimates of nutrient residue stocks. Therefore, there is an obvious need for detailed methods that capture spatial difference in residue properties and identify the areas which actively release nutrients.

How will this be achieved: FERRO’s input

To identify soft and rich in nutrients residue “which is responsible for identifying high levels of phosphorus and ammonium release,” FERRO’s approach uses sonar-based analysis. By finding the residue density across entire lakes, the sonar gives highly structural resolution estimates of their properties. These estimates enable the classification of internal loading hotspots in shallow and deep lakes. 

Who will benefit from this?

Experts involved in the lakes management and restoration will have access to explicit and precise information, allowing restoration measures to be customised to specific areas: those releasing nutrients actively. The field authorities and policymakers will benefit from improved assessments of residue phosphorus stocks and internal loading. This will support more reliable planning, reporting and decision-making.

By enabling targeted intervention and post-restoration evaluation, this approach contributes to more efficient nutrient management and improved ecological status of eutrophic lakes.