Diversifying crop rotations with temporary grasslands - Université de ...

• Which species are suppressed, which are favoured in and after PFCs? Do perennial crops
reduce the problem of some weed species and create others?
• Do weed species with similar biological response traits (functional groups) react in similar
ways?
• What are the most important mechanisms behind the impacts?
• What grassland management options are most appropriate?
A.VI.2 Structure of the thesis
This thesis analyzing the impacts of PFCs on weeds comprises a literature review that is
included in the General Introduction (section A.IV.1) and four empirical chapters (C.I - C.IV)
corresponding to four research approaches, that are organized on a hierarchical scale
(illustrated in Fig. 8).
“Impact of perennial forage crops on weeds”
A.IV.1 Literature review
C.I Impacts on weed communities (surveys on commercial fields, Chizé)
C.II Impacts on weed populations & communities (field experiments, Epoisses)
C.III Impacts on individual plants:
survival and regrowth after cutting
(greenhouse experiments, Dijon)
Weed
species
number
Level of
abstraction
Fig. 8: Structure of the research project showing 4 empirical approaches.
The first empirical chapter C.I deals with the impacts of crop rotations including PFCs on
weed communities. It is based on weed surveys over a large number of commercial fields in
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C.IV Impacts on seeds:
weed seed predation
(field experiments, Epoisses)
Spatiotemporal
scale