Context and aims
Riparian forests are a central element of river landscapes. In Mediterranean and semi-arid regions they emerge from the surrounding landscape matrix as “linear oasis”, and contain a disproportionate share of regional biodiversity. Besides the unquestionably ecological value, riparian forests provide goods and numerous societal and economic benefits, including flood mitigation, aquifer recharge, and maintenance of water quality. We propose a functional trait-based approach developed under an hybrid framework methodology to determine environmental flows for riparian vegetation and the river ecosystem, i.e the quantity and timing of water flows required to sustain the proper ecosystems’ functioning in regulated rivers.

Scientific Tasks
The project was founded in three highly-connected tasks, according to four processes: i) obtaining and systematizing riparian and ii) hydrological information, iii) model development and calibration, iv) model validation and testing for different flow scenarios and cost analysis.

Task 1: FLOWBASE, on-line database on flow-response traits of riparian plants
1. List of relevant riparian woody species
2. Data compilation on plant functional traits and riparian species
3. Data compilation on geographic location of species, landscape images and other data
4. Implementation and design of the database

Task 2: Riparian Vegetation-Flow Response Guilds
1. Selection of case studies;
2. Gathering hydrological data and modelling of natural flows, gathering biological data and field work;
3. Calculation of ecologically meaningful statistical metrics of hydrological alteration;
4. Analysis of riparian plant responses to flow alterations;
5. Selection of the best hydrological predictors and riparian guilds;
6. Development of probabilistic models.

Task 3: Decision models
1. Development of a conceptual model of cause-effect relationships between flow patterns and key riparian vegetation guilds;
2. Use of Bayesian networks in different flow scenarios for different magnitudes and frequencies of flushing flows and summer flows, and determining different levels of the maintenance of the riparian forests.
3. Use of Bayesian Decision Networks to evaluate cost and utility functions, for management of these different flow scenarios.