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.

Linking species traits to agroecosystem services: a functional analysis of weed communities

“…A further strength of our database is its Europe‐wide coverage in terms of species, which should make it useful or easily adaptable to a variety of arable cropping systems across the continent, as in the case of the supporting trials. Previously developed weed traitbases (Storkey et al ., ) are more comprehensive in terms of data completeness, but address a lower number of species. On the other hand, other extensive plant trait databases (e.g.…”

Response and effect traits of arable weeds in agro‐ecosystems: a review of current knowledge

“…These sources are not restricted to weeds, but rather consider the full European or World flora. WTDB (Storkey et al ., ) or Weed‐Data (Gaba et al ., ) are databases restricted to weeds. These databases provide data on vegetative and reproductive traits and potentially whole‐plant performance traits.…”

“…Robust stable links across wide gradients of disturbances and spatial variation have been established between the functional traits of weeds and carabids, and their trophic interactions (Brooks et al ., ). However, while weed response traits to management has been widely investigated (see for instance Storkey et al ., ), no study, to our knowledge, has proposed a holistic synthesis of the current knowledge on weed response and effect functional traits (Fig. ).…”

Quantification of regulating ecosystem services provided by weeds in annual cropping systems using a systematic map approach

“…However, many of the available traits are response traits ( sensu Lavorel & Garnier, ), while the effect traits available are mostly limited to provisioning of floral resources to arthropods. Furthermore, it must also be taken into consideration that traits measured from the spontaneous vegetation may be slightly different from the traits observed in the same species grown in cropped systems (Storkey et al ., ), and therefore, fundamental research on weed species traits in relation to ecosystem service provisioning potential would be recommended.…”