title: A biological tool to assess flow connectivity in reference temporary streams from the Mediterranean Basin.
abstract: Many streams in the Mediterranean Basin have temporary flow regimes. While timing for seasonal drought is predictable, they undergo strong inter-annual variability in flow intensity. This high hydrological variability and associated ecological responses challenge the ecological status assessment of temporary streams, particularly when setting reference conditions. This study examined the effects of flow connectivity in aquatic macroinvertebrates from seven reference temporary streams across the Mediterranean Basin where hydrological variability and flow conditions are well studied. We tested for the effect of flow cessation on two streamflow indices and on community composition, and, by performing random forest and classification tree analyses we identified important biological predictors for classifying the aquatic state either as flowing or disconnected pools. Flow cessation was critical for one of the streamflow indices studied and for community composition. Macroinvertebrate families found to be important for classifying the aquatic state were Hydrophilidae, Simuliidae, Hydropsychidae, Planorbiidae, Heptageniidae and Gerridae. For biological traits, trait categories associated to feeding habits, food, locomotion and substrate relation were the most important and provided more accurate predictions compared to taxonomy. A combination of selected metrics and associated thresholds based on the most important biological predictors (i.e. Bio-AS Tool) were proposed in order to assess the aquatic state in reference temporary streams, especially in the absence of hydrological data. Although further development is needed, the tool can be of particular interest for monitoring, restoration, and conservation purposes, representing an important step towards an adequate management of temporary rivers not only in the Mediterranean Basin but also in other regions vulnerable to the effects of climate change.
authors.affiliation: Grup de Recerca "Freshwater Ecology and Management (FEM)", Departament d'Ecologia, Universitat de Barcelona, Catalonia, Spain. Electronic address: ncid@ub.edu.
authors.forename: N
authors.initials: N
authors.lastname: Cid
authors.affiliation: Grup de Recerca "Freshwater Ecology and Management (FEM)", Departament d'Ecologia, Universitat de Barcelona, Catalonia, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Verkaik
authors.affiliation: Grup de Recerca "Freshwater Ecology and Management (FEM)", Departament d'Ecologia, Universitat de Barcelona, Catalonia, Spain; Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Spain.
authors.forename: E M
authors.initials: EM
authors.lastname: García-Roger
authors.affiliation: Grup de Recerca "Freshwater Ecology and Management (FEM)", Departament d'Ecologia, Universitat de Barcelona, Catalonia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Rieradevall
authors.affiliation: Grup de Recerca "Freshwater Ecology and Management (FEM)", Departament d'Ecologia, Universitat de Barcelona, Catalonia, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Bonada
authors.affiliation: Department of Ecology and Hydrology, Regional Campus of International Excellence "Campus Mare Nostrum"-University of Murcia, Spain; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany.
authors.forename: M M
authors.initials: MM
authors.lastname: Sánchez-Montoya
authors.affiliation: Department of Ecology and Hydrology, Regional Campus of International Excellence "Campus Mare Nostrum"-University of Murcia, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Gómez
authors.affiliation: Department of Ecology and Hydrology, Regional Campus of International Excellence "Campus Mare Nostrum"-University of Murcia, Spain.
authors.forename: M L
authors.initials: ML
authors.lastname: Suárez
authors.affiliation: Department of Ecology and Hydrology, Regional Campus of International Excellence "Campus Mare Nostrum"-University of Murcia, Spain.
authors.forename: M R
authors.initials: MR
authors.lastname: Vidal-Abarca
authors.affiliation: Instituto di Ricerca Sulle Acque (CNR-IRSA), Italy.
authors.forename: D
authors.initials: D
authors.lastname: Demartini
authors.affiliation: Instituto di Ricerca Sulle Acque (CNR-IRSA), Italy.
authors.forename: A
authors.initials: A
authors.lastname: Buffagni
authors.affiliation: Instituto di Ricerca Sulle Acque (CNR-IRSA), Italy.
authors.forename: S
authors.initials: S
authors.lastname: Erba
authors.affiliation: Hellenic Center for Marine Research (HCMR), Greece.
authors.forename: I
authors.initials: I
authors.lastname: Karaouzas
authors.affiliation: Hellenic Center for Marine Research (HCMR), Greece.
authors.forename: N
authors.initials: N
authors.lastname: Skoulikidis
authors.affiliation: Grup de Recerca "Freshwater Ecology and Management (FEM)", Departament d'Ecologia, Universitat de Barcelona, Catalonia, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Prat
mesh_terms: D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D062070:Hydrology; D019083:Mediterranean Region; D045483:Rivers / Q000737:chemistry*; D014872:Water Movements; D014881:Water Supply / Q000706:statistics & numerical data
keywords: Biological traits; Ecological status; Hydrological variability; Macroinvertebrates; Mediterranean Basin; Reference conditions