title: Combining a weed traits database with a population dynamics model predicts shifts in weed communities.
abstract: A functional approach to predicting shifts in weed floras in response to management or environmental change requires the combination of data on weed traits with analytical frameworks that capture the filtering effect of selection pressures on traits. A weed traits database (WTDB) was designed, populated and analysed, initially using data for 19 common European weeds, to begin to consolidate trait data in a single repository. The initial choice of traits was driven by the requirements of empirical models of weed population dynamics to identify correlations between traits and model parameters. These relationships were used to build a generic model, operating at the level of functional traits, to simulate the impact of increasing herbicide and fertiliser use on virtual weeds along gradients of seed weight and maximum height. The model generated 'fitness contours' (defined as population growth rates) within this trait space in different scenarios, onto which two sets of weed species, defined as common or declining in the UK, were mapped. The effect of increasing inputs on the weed flora was successfully simulated; 77% of common species were predicted to have stable or increasing populations under high fertiliser and herbicide use, in contrast with only 29% of the species that have declined. Future development of the WTDB will aim to increase the number of species covered, incorporate a wider range of traits and analyse intraspecific variability under contrasting management and environments.
authors.affiliation: Agroecology Department, Rothamsted Research Harpenden, UK.
authors.forename: J
authors.initials: J
authors.lastname: Storkey
authors.affiliation: Department of Agroecology, Aarhus University Slagelse, Denmark.
authors.forename: N
authors.initials: N
authors.lastname: Holst
authors.affiliation: Department of Agroecology, Aarhus University Slagelse, Denmark.
authors.forename: O Q
authors.initials: OQ
authors.lastname: Bøjer
authors.affiliation: Istituto di Scienze della Vita, Scuola Superiore Sant'Anna - Piazza Martiri della Libertà Pisa, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Bigongiali
authors.affiliation: Istituto di Scienze della Vita, Scuola Superiore Sant'Anna - Piazza Martiri della Libertà Pisa, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Bocci
authors.affiliation: INRA, UMR1347 Agroécologie Dijon, France.
authors.forename: N
authors.initials: N
authors.lastname: Colbach
authors.affiliation: Institute of Plant Protection, Faculty of Agriculture & Environmental Science, Szent Istvan University Godollo, Hungary.
authors.forename: Z
authors.initials: Z
authors.lastname: Dorner
authors.affiliation: Wageningen University & Research Centre, Agrosystems Research Wageningen, the Netherlands.
authors.forename: M M
authors.initials: MM
authors.lastname: Riemens
authors.affiliation: Istituto di Biologia Agroambientale & Forestale, CNR Padua, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Sartorato
authors.affiliation: Department of Agroecology, Aarhus University Slagelse, Denmark.
authors.forename: M
authors.initials: M
authors.lastname: Sønderskov
authors.affiliation: Federal Research Centre for Cultivated Plants, Julius Kuhn Institute Braunschweig, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Verschwele
keywords: agricultural intensification; community assembly theory; demographic model; functional ecology; weed management