Adaptation of water and land management is essential in the Mediterranean basin, which faced overexploitation of water / soil resources and will experience important hazards due to change in climate forcing. Meeting the growing demand for food and water requires rationales for designing innovative solutions in agricultural land use planning and practices, so that stakeholders can setup trade-offs between various needs at different levels. In the context of rainfed and irrigated agriculture, innovative solutions must aim to better collect, store, distribute and use water resources. Water resource managers are looking, among other, for decision support system tools based on the modulation of spatial structures and connectivities induced by hydro-agricultural practices and infrastructures. Existing integrated water management frameworks do not explicitly account for spatial structures and connectivities in relation to hydro-agricultural practices and infrastructures. Meanwhile, several progresses were made the last decade when addressing spatial structures and connectivities in relation to 1) their geometries and hydro-dynamical properties, 2) their influences on matter fluxes, 3) their inclusion into integrated modelling schemes and mechanistic models, and 4) their inclusion into possible evolutions of territorial water governance. Nowadays, it is necessary to sustain efforts on these progresses and to capitalise on recent advances.
The overall objective of the ALTOS project is to improve water management models for rainfed and irrigated agriculture, by considering the modulation of spatial structures and connectivities induced by hydro-agricultural infrastructures and practices, as an innovative tool for rational use / protection of water resources.
- We address the modulation of structures related to (1) hydro-agricultural practices (land use, heterogeneous canopies such as inter-cropping and orchards, irrigation techniques) and (2) infrastructures (water-harvesting systems such as benches and reservoirs).
- Along with spatial structures, we consider connectivities through water fluxes, including (1) surface connectivities related to surface runoff, and (2) subsurface connectivities related to infiltration and percolation.
- We assess the impacts of spatial structure modulation on first-order matter fluxes and storages, including (1) blue water compartments for artificial and natural storages (depletion and re-charge for reservoirs and aquifers), and (2) green water compartments for dependent agroecosystems (root zone water dynamics and related agricultural production).
- In a lesser extent, we study the modulation of farming inputs related to chemical treatments, and the resulting impacts on the water resources stored within surface reservoirs and aquifers.
To achieve the overall goal discussed above, ALTOS analyses the impacts of modulation scenarios on matter fluxes and storages. Therefore, ALTOS aims to pursue and achieve the following specific objectives.
- Designing innovative methodologies for monitoring, characterising and digitally representing spatial structures and connectivities, as well as designing innovative methodologies for monitoring and understanding water flows and storages driven by spatial structures and connectivities.
- Modelling water flows and storages driven by spatial structures and connectivities. The goal is to (1) design innovative models that simulate matter fluxes and storages, with implicit descriptions through equivalent parameterisations, (2) include these innovative models within integrated modelling schemes, and (3) conduct model calibrations / validations using historical time series.
- Emphasising the interest of updated modelling schemes by (1) designing modulations for spatial structures and connectivities, to be combined with changes in climate forcing, and (2) quantifying the resulting impacts on matter fluxes and storages within targeted compartments (blue and green water), on the basis of simulations from calibrated models.
- Quantifying benefits for water management by analysing scenario impacts with stakeholder having convergent / divergent viewpoints (water management authorities, agricultural development commissions, farmer associations within rainfed catchments and irrigated perimeters).
ALTOS mobilises a large panel of existing materials and partnerships for both research (e.g., datasets, modelling schemes, integrated analysis with participative seminars), and impact (collaboration with water management authorities and engineering offices through community facilities such as observatories, joint laboratories, and modelling platforms). It also benefits from long-term institutional programs such as environmental research observatories, international joint laboratories, and modelling platforms, so called hereafter community facilities.
- The OMERE, Tensift, Merguellil and O-LIFE environmental research observatories are dedicated to the multi-decadal monitoring of water resources under climate / anthropogenic changes, including the gathering, processing and dissemination of data by following EU standards (e.g., INSPIRE).
- The IRD TREMA & NAILA joint international laboratories and the CNRS O-LIFE associated laboratory are international collaborative structures that aim to gather complementary competences towards common objectives for re-search, training and knowledge transfer. These international laboratories address the functioning and fate of Mediterranean agrosystems in relation to soil and water resources, by designing innovative means for monitoring, modelling and integrated analysis.
- The OpenFLUID project aims to develop and disseminate a software platform that provides a fully featured environment for spatial modelling of landscapes dynamics. The platform is based on a modular structure, which permits to implement modelling and simulation approaches from model development to executions and simulation analyses. The platform also permits to account for spatial connectivities thanks to graph theory, and to manage various spatial and times scales during simulations.