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PsychoPharmaca effect on biofilms and algae populations with mitigation approach using nature-based solutions. This proposal focuses on studying the effects of psychotropic drugs such as antidepressants and antipsychotics on aquatic biofilms. The effect on algae populations is studied by performing a competition experiment on two types of algae with the presence of psychotropic drugs: fluoxitene (prozac). In addition, a mitigation approach is being evaluated for these chemicals, with reduction through water treatment via technology using nature-based solutions.

Restoring large grazers through strategic reintroduction or passive management offers hope to halt biodiversity loss and enhance coastal climate resilience. However, the effectiveness and optimal conditions remain unclear. WildMarsh establishes a robust scientific foundation, identifying hopeful sites in Europe where grazers can bolster marsh resilience against climate challenges (such as sea-level rise, heatwaves). Scientists and stakeholders will develop innovative tools for remote rewilding impact measurement and ecosystem resilience assessment, engaging the public in data collection and art. Utilizing advanced ecological experiments, remote sensing, deep learning, and citizen science, WildMarsh paves the way for a more resilient future for wild coastlines.

Seagrass ecosystems are essential components of coastal zones, due to their extremely high productivity and the high biodiversity they support. Humans depend on seagrass meadows because they serve as nutrient and carbon sinks, fishing grounds and storm buffers. However, seagrass communities are increasingly subject to multiple human-induced global changes, including on the one hand defaunation (i.e. removal of large animals from ecosystems), and on the other hand invasive species expansion. An urgent and open question is how these alterations interactively affect the functioning and services of ecosystems. I aim to clarify how large herbivores and exotic plant species affect the multiple ecosystem services of seagrass beds. To achieve this, I will compare important seagrass ecosystem services under grazed and ungrazed conditions (with Green sea turtles as large herbivores), with and without invasive seagrass, at different spatial scales. I will use a multi-disciplinary approach combining: 1) large-herbivore exclosure experiments (on Bonaire) with manipulated densities of invasive seagrass, and simultaneous measurements of 6 key ecosystem services, 2) a regional upscaling (Caribbean Sea) to examine how spatial grazing patterns of large herbivores and prevalence of invasive seagrass change underwater landscapes and seagrass bed services, 3) a literature review and 4) a global initiative to develop tools for mapping (invasive) seagrass biomass by using green turtles foraging movements. Together, this research will demonstrate the consequences of defaunation and plant invasion for seagrass bed ecosystem services. This will facilitate predicting the adaptive capacity of seagrass ecosystems, and large herbivores that rely on them, under different scenarios of human-induced global change. Furthermore, the proposed research will identify pathways for effective management of critical seagrass habitat through management of its herbivores and their predators. The knowledge gained in this research is urgently needed to safeguard human wellbeing, which depends on the provided seagrass ecosystem services.

Water quality in shallow Lake Taihu, China, has rapidly deteriorated in the past decades due to rapid urbanization and changed land use, resulting in severe blooms of toxic cyonabacteria (figure 1) and reduction of submerged macrophytes. Climate change has intensified these problems. This study on Lake Taihu has six key objectives: 1) assess current ecosystem health; 2) identify the desired ecological quality; 3) identify critical levels of nutrient loading necessary to reach this quality; 4) identify the uncertainty in these critical levels; and 5) evaluate scenarios that mitigate eutrophication and other major stressors on ecosystem health. We want to identify the critical nutrient loadings for Lake Taihu with a model for integrated water system research. These critical nutrient loadings define the points at which the lake suddenly switches from a good ecological quality into a bad ecological quality and vice versa. In Europe, knowledge of critical loadings has become very important due to the EU Water Framework Directive that imposes high quality standards for all water bodies in 2015. The focus on critical nutrient loading is original and innovative. While the concept of nutrient loading as such is key to any limnological study on lake eutrophication, the concept of critical nutrient loading has only emerged when it became apparent that ecosystems often respond in a non-linear way to external stressors. A key innovative element in the topic of this project is therefore that we study nutrient loadings in the light the positive feedbacks that maintain alternative stable ecosystem states. We will use the existing ecosystem model PCLake as a template for our ecosystem model of Lake Taihu. PCLake has been developed, tested and implemented as an important tool for managing water quality in shallow lakes in the Netherlands and a formal protocol for analyzing uncertainty in model output is available.