Integrated Research Project

• Thesis title: LITOSMED
• Type of project: Research
• Event: 2022

The LITOSMED project studies emissions of Volatile Organic Compounds (VOCs), mainly biogenic (VBOCs), from plant litter in Mediterranean urban and forest environments. These compounds play an important role in tropospheric ozone and secondary organic aerosol (SOA) training, affecting air quality and ecosystems.

Although "green" vegetation is frequently studied as a source of VOCs, litter, which represents a biomass of decaying leaves, is rarely addressed. Yet it is a significant source of VOCs, often overlooked, and could contribute to the training of AOS.

The objectives of the LITOSMED project are :

1. Characterize the emissions of VOCBs from urban and forest litter, while assessing their degradation via ecological indicators.
2. Study the capacity of these VOCBs to generate AOS by reacting with atmospheric oxidants.

These studies will be carried out in forest and urban environments in the Sud-PACA region, simulating different climate scenarios and taking into account the diversity of plant species. Research, conducted in collaboration with landscaping professionals, aims to improve the management of urban green spaces and air quality by taking into account the state of litter degradation.

• Thesis title: Transivir
• Type of project: Research
• Event: 2022

The TRANSIVIR project focuses on the interactions between viruses and phytoplankton communities in Mediterranean ponds impacted by climate change, as well as on the microalgae used to capture industrial CO₂. This Research focuses on two major objectives.

The first is to analyze the biological and ecological role of phycocyanobilin, a synthesis pathway recently discovered in giant viruses infecting Picochlorum. This unicellular alga is responsible for the harmful green tides observed in the Etang de Thau, a key Mediterranean ecosystem.

The second objective is to develop an innovative method based on fluorescence cell sorting. This technique will make it possible to identify virus-infected microorganisms, in particular those that have hitherto only been detected by metagenomics, without identifying their specific hosts.

The expected results should lead to a better understanding of the interactions between viruses and a key algal species in ecological and socio-economic terms. In addition, this methodological breakthrough will fill a major gap in environmental virology, providing a precise inventory of host-virus relationships. This knowledge will offer a new perspective on the role of viruses in Mediterranean ecosystems in transition.

• Thesis title: Hyflex
• Type of project: Research
• Event: 2022

The development of hydrogen as an alternative to hydrocarbons is part of a move to decarbonize human activities. This transition offers major advantages, such as reduced methane emissions, support for reindustrialization and greater mobilization for the climate. However, it is accompanied by environmental risks, notably hydrogen leakage, which amplifies the greenhouse effect, increases tropospheric ozone pollution and damages the ozone layer. On a socio-political level, issues such as conflicts of use, lack of transparency and financial and health risks must also be taken into account.

A multi-disciplinary research program is exploring these benefits and risks, drawing on the environmental and social sciences. The aim is to better understand the interactions between these factors, their influence on project design and their acceptability in a context of contradictory forces and changing opportunities.

• Thesis title: Projet trajectoires
• Type of project: Research
• Event: 2024

The TRAJECTOIRES project focuses on urban wastelands in the context of ecological and social transitions. It aims to understand their multifunctionality and their role in the city of tomorrow. Brownfields are often perceived as building sites, yet they present both ecological (biodiversity, limiting heat islands) and social (nature areas, ecological corridors) challenges.

As part of a reflection on land sobriety and new development policies (such as the "Zero Net Artificialization" law), this interdisciplinary project explores :

• The ecological and social roles of wasteland: biodiversity, ecosystem services, urban uses.
• Possible trajectories: rehabilitation, conservation, or mixed uses, for a livable and resilient city.

Using Marseille as an example, the program proposes an approach integrating urban planning, geography, ecology and social sciences to analyze and develop these spaces in the collective interest.