Ocean-biosphere interactions

Marine biodiversity is a cornerstone of global ecological health, underpinning essential ecosystem services and supporting livelihoods around the world. However, ocean ecosystems are increasingly under pressure from a range of human-driven and environmental stressors, including overfishing, climate change, ocean warming, acidification, habitat destruction, and pollution. Addressing the interconnected crises of biodiversity loss and climate change has therefore become an urgent global priority.

A key challenge lies in understanding how biodiversity contributes to the stability and resilience of marine ecosystems. While research has made significant progress in certain regions and habitats, major knowledge gaps remain—particularly in remote and understudied environments such as the deep sea, the open ocean, and polar ecosystems. Comprehensive, large-scale research efforts are essential to better understand these systems and to establish reliable baselines for biodiversity, against which future changes can be measured.

Marine biodiversity is closely linked to climate-relevant processes, including carbon cycling, carbon storage, and biogeochemical feedback mechanisms. The loss of biodiversity is expected to have profound consequences for ecosystem functioning, although many of the underlying processes are not yet fully understood. In particular, the interactions between species—such as predator-prey relationships and food web dynamics—are highly sensitive to environmental change. Shifts in temperature and other factors can disrupt the timing between food availability and organism needs, affecting survival, reproduction, and overall ecosystem productivity.

To better understand these dynamics and improve predictions of future ocean conditions, it is also essential to investigate past climate variability and its impact on biodiversity. Natural archives, such as marine sediments and ice cores, provide valuable insights into long-term ecological and environmental changes. Combined with advanced modeling approaches, these data help to reconstruct past ecosystems and refine projections of future developments.

Building on these foundations, several key research areas are central to advancing our understanding of marine biodiversity:

• Long-term monitoring of marine ecosystems: Sustained observation programs are critical for detecting changes in biodiversity over time. High-resolution, long-term datasets enable researchers to track shifts in species distribution, community composition, and ecosystem functioning. These efforts also support the development and management of Marine Protected Areas and contribute to effective conservation strategies.
• Comprehensive biodiversity studies across habitats: Modern research vessels equipped with advanced technologies allow scientists to investigate marine life across all scales—from microorganisms to larger organisms—and across diverse habitats, from coastal zones to the deep sea. In particular, marine microorganisms play a fundamental role in nutrient cycling, carbon fixation, and overall ecosystem functioning, yet remain insufficiently explored.
• Invasive species and ecosystem connectivity: The spread of non-indigenous species, facilitated by global shipping and changing environmental conditions, poses a growing threat to marine ecosystems. Research focuses on identifying these species, understanding their pathways of introduction, and assessing their ecological impacts, including competition with native species and the spread of diseases.
• Functional and adaptive processes in marine organisms: Advances in molecular and experimental techniques enable detailed studies of the physiological, genetic, and biochemical mechanisms that govern how organisms respond to environmental change. These insights are essential for understanding the adaptive capacity of species and the resilience of ecosystems under future climate scenarios.
• Unique ecosystems and connectivity in the deep ocean: Extreme environments such as deep-sea hydrothermal vents host highly specialized and productive ecosystems. Studying these “oases of life” provides valuable insights into biodiversity, biogeochemical processes, and the dispersal and connectivity of species across the global ocean.

Through these research efforts, the program contributes to a deeper understanding of marine biodiversity and its critical role in sustaining ocean health. This knowledge is essential for developing effective strategies to protect marine ecosystems, mitigate the impacts of climate change, and ensure the sustainable use of ocean resources.