Functional trait expression under environmental change

The coasts and shelf seas that surround us have been the focal point of human prosperity and well-being throughout history. Their societal importance extends beyond food production, and includes biodiversity, nutrient cycling, recreation, and renewable energy. As coastal population densities are rising, these ecological benefits become progressively compromised by human activities, overfishing, pollution, habitat disturbance, climate change. Importantly, sediment communities that harbour high levels of biodiversity are particularly affected, because most species are unable to move to avoid disturbance. This is worrying because seabed condition, biodiversity and human society are inextricably linked. It is important, therefore, to be able to assess and understand how the ecological condition of the seabed relates to the provision of ecosystem benefits so that human pressures can be managed more effectively to ensure the long-term sustainability of our seas.

Scientific research has considered species roles in the environment and the ecological consequences of biodiversity loss. From this body of work, it has been possible to construct projections of future environmental condition and associated societal benefits. These models largely assume that the roles of species and how they respond to perturbation are well defined and characterised. But these assumptions are based on present-day conditions and have seldom been objectively validated or experimentally tested under anticipated future conditions. This is worrying because Government agencies and other bodies tasked with managing the marine environment use these model projections to plan for the future. Hence, there is an urgent need to understand how species respond to and effect ecosystem properties prior to, during and post disturbance events. The capacity of different species to mediate ecosystem properties will depend on the contributory role of each species, as some species will be insensitive to disturbance, while others will be more vulnerable to change. The
balance of these responses will determine the seabed's capacity to provide goods and services, which makes it very difficult to assess species sensitivities or make general statements about what benefits we can expect from our seas in the future.

We will address these shortcomings by bringing together scientists with expertise in ecology, physiology, genetics, and numerical modelling to test how key species respond to and affect ecosystem properties under present and future conditions. We will see how different types of disturbance alter species behaviour and, subsequently, affect ecosystem properties (e.g., nutrient cycling). Nutrients are important as they support the growth of phytoplankton and algae, which underpin the ocean's food web. In our experiments, we will record the levels of nutrients released into the water due to sediment mixing by worms, clams, urchins, and brittle stars. By doing this for a range of environmental conditions (abrupt vs. long-term forcing) we will establish how exposure to different disturbance regimes, and their combinations, affect these important processes. We will determine the physiological performance of each species by measuring the molecular mechanisms that underpin adaptation. This will tell us whether species are able to adapt to new environmental conditions and whether such adaptive adjustments impinge on other important species roles. By matching the nutrient and sediment mixing data with physiological conditions across multiple generations, we will considerably improve understanding of how species may respond to future environments and, in turn, affect major ecosystem properties. We will use this information to co-design and implement, with Cefas, a new model that adequately characterises species contributions under changing conditions, to deliver accurate forecasts of ecosystem integrity in support of policy.