Eutrophication is a worldwide societal and environmental issue related to nutrient-rich river inputs. Land-sea modeling is an essential tool to understand the non-linear relationships between nutrient loads and eutrophication symptoms, and to investigate prospective trends. If few initiatives have started to develop land-sea modeling since 2000s, more developments are needed to achieve an integrated land-sea model that could be used to take into account the complexity and dynamic of land-sea socio-ecosystems, disentangle the role of direct anthropogenic pressures and climate change in eutrophication trends, and identify the changes in practices/uses/regulation/system necessary to avoid eutrophication in a context of climate change. Aquatic processes are relatively well constrained, but the choice of terrestrial models, where solutions can be implemented, need to be done with stakeholders. Indeed, improving quantitative modeling through transdisciplinary (participatory) approaches is rare but essential to improve models with local knowledge and foster confidence and understanding of models by stakeholders. Participation is also needed to ensure the co-construction and appropriation of knowledge, the facilitation of dialogue between stakeholders, and the implementation of sustainable management strategies and decision making along the land-sea continuum. The objectives of MOQQA are to develop generic methodologies based on a suite of participatory qualitative and quantitative modeling approaches to (1) understand complex land-sea (environmental and social) relationships, (2) increase non-scientific knowledge integration to improve land-sea modeling, (3) model the cascade of impacts on hydro-biogeochemistry, eutrophication symptoms, food webs and marine resources, (4) investigate conditions for sustainable socio-ecosystem trajectories in the future, and (5) foster co-adaptative management along the land-sea continuum. The methodology aims at being transposable to any land-sea socio-ecosystem and will be first developed in a pilot site, the Bay of Brest and its watersheds. Expected results are (1) a shared qualitative model of the land-sea socio-ecosystem around eutrophication issues integrating view points and representations of a wide diversity of stakeholders, (2) a functional land-sea physical-biogeochemical-ecological model adapted to the Bay of Brest and its watersheds and enriched by local stakeholder knowledge, (3) a list of pertinent and consistent interdisciplinary indicators and scales to qualify the ecological status along the land-sea continuum, (4) a set of potential ecosystem trajectories related to different practices or management strategies, and (5) the identification of a series of blocks and levers for action. Overall, MOQQA aims at providing (6) a transposable participatory methodology based on qualitative and quantitative modeling to help to overpass land/sea dichotomy and be more integrative with local stakeholder. The main expected impacts of MOQUA are methodologic, scientific, societal and pedagogic. MOQQA will develop transposable methodologies through deeply inter and transdisciplinary approaches, in order to improve the understanding of complex socio-ecosystems at the land-sea interface. MOQQA will also foster co-adaptative management, including by proposing a transposable approach of local implementation of European directives grids of indicators. Finally, pedagogic and mediation impacts will arise from the creation of innovative pedagogic tools for agricultural scholars and students, the training of early-career scientists and outreach towards the civil society.

The ultimate goal of the proposal is to assess the current Ecological Quality (EcoQ) of coastal and littoral benthic habitats in Metropolitan France. It thus addresses fundamental scientific questions that will find immediate as well as long-term use for public action. Its specific objectives are to validate, develop and apply methods that rely on biological community data (composition, structure and function) and sediment imagery to characterise the ecological state of marine habitats. The RÉseau des Stations et Observatoires MARins (RESOMAR, INSU, CNRS) aims to federate coastal marine biology research at the national level. In 2007 it undertook the task of implementing databases of current and historical datasets relating to benthic and pelagic compartments of Metropolitan France costal and littoral ecosystems. RESOMAR Benthic Macrofauna DataBase (BMDB) presently holds 106 datasets containing macrofaunal abundances and biomass for a total of 9,957 sampling stations. It spans a 50-year time period (1961 to present) and covers France’s entire metropolitan coastline. The BMDB notably includes most datasets acquired within the WFD and the Habitats Directive in Metropolitan France. The BMDB is to be used to answer difficult scientific questions at spatial scales beyond that of the single marine station. It is thus particularly well adapted to tackle questions raised by the application of the WFD, the Habitats Directive and the MSFD. The spatiotemporal scope of the database will first allow an analysis of natural variation patterns in marine benthic communities. This will, allow the identification of characteristic spatial and temporal scales of variations and their consideration in subsequent analysis. Indeed, variability attributable to seasonal, other cyclic phenomenon, or changes in meteorological conditions, must be taken into account when assessing EcoQ : these parameters are, a priori, not linked to disturbance gradients and should not influence EcoQ evaluation. The Biotic Indices (BI) currently used within the WFD will be compared among themselves and others in order to evaluate their relative performance and how they relate to each other. New indices, based on the concept of multidimensional deviation in community structure from a reference condition, will be developed and compared to existing ones. The innovative method of Sediment Profile Imagery will also be used to obtain and evaluate independent estimates of EcoQ. Considering the spatial scope targeted by the MSFD and the time and resource consuming aspect of actual faunal community sampling, it appears necessary to develop and validate cost-effective complementary methods. This research will tackle the relationship between various types of disturbances and EcoQ assessment. Indeed, anthropic pressure data should be related to variation in Macrofaunal benthic community structure. Ideally, disturbance data should be of a quantitative nature, but semi-quantitative can be accommodated in statistical models. Although past research has mainly focused on disturbances related to organic enrichment, the current project will focus on multiple types of disturbances (e.g. trawling, water treatment stations, aggregate extraction, dredging, etc.) that can have different impact on community structure. In whole, the joint analysis of disturbance and community data will allow to confirm whether a BI can adequately describe the EcoQ of habitats submitted to different anthropic pressures.