Designing farmer-acceptable rotations that assure ecosystem service provision in the face of climate change

Inferring species interactions from ecological survey data: A mechanistic approach to predict quantitative food webs of seed feeding by carabid beetles

“…The predation pressure for each seed genus in each field varied substantially: Smaller seeds tended to have higher predation pressure than larger ones (effect size ± standard error (SE) = −0.429 (0.020); Figure 6b ), and it varied by the crop type: Beet fields had the highest predation pressure ratio; maize was no different to beet (effect size ± SE compared to beet = −0.293 ± 0.196), spring‐sown oilseed rape was lower (−0.840 ± 0.180 compared to beet), and winter‐sown oilseed rape was lowest (−1.639 ± 0.182 compared to beet). Suitable empirical data are not yet available to validate these models, but these summary trends provide testable hypotheses about the network‐derived ecosystem function of carabids in these fields (Bohan et al., 2021 ).…”

“…Here, we developed a new metric derived from the quantitative network structure: the predation pressure ratio, to explain the predicted predation rate relative to the seed abundance. Recently, we found that the predation pressure ratio was valuable in explaining variation in weed seed dynamics, and more valuable than carabid abundance alone (Bohan et al., 2021 ). This supports our approach being ecologically meaningful.…”

“…Ultimately, the inference of interactions and the construction of potential food webs would extend the use and value of existing ecological census data. The inferred networks could then be used in ecosystem modeling or as null models to improve mechanistic understanding of species interactions (Bohan et al., 2021 ; Ma et al., 2019 ). The ecological census data we used here were two decades old and, so where suitable ecological census data exist, it could be possible to construct historical inferred networks from ecological census data, and for guilds where interaction data are difficult to obtain directly, such as many insectivorous predators.…”

Building capacities for the design of agroecological landscapes: The added-value of Landscape Monitoring Networks

“…Besides, owing to the large sampling effort required in landscape studies, patterns observed are usually a snapshot, one year in one crop type, and this restricted spatio-temporal scope limits our capacity to understand processes underlying the provision of pest control services. For example, little knowledge is available regarding the pest control benefits of farming management across the crop rotation (Kleijn et al, 2019;Bohan et al, 2021), the temporal stability of pest control services within and between years and the role of abiotic variables (e.g. climatic conditions) in the dynamics of organisms delivering pest control services.…”

Protéger les cultures par la diversité végétale

“…Les mélanges de cultures de rente représentent aujourd'hui 0,1 à 3 % de la sole selon les régions, et sont principalement des associations céréales -protéagineux. Bohan et al (2011Bohan et al ( , 2021 préconisent des rotations en grandes cultures de plus de 3 ans, diversifiant les périodes de culture (cultures d'hiver et de printemps) et en insérant si possible des Brassicacées, pour réguler notamment les adventices, et des légumineuses pour la fixation de l'azote. Actuellement, la majorité des surfaces en grandes cultures portent des rotations de 3 cultures maximum (avec une prédominance des triplets de cultures incluant le colza, le blé et l'orge), et les monocultures occupaient 12 % de ces surfaces en 2006.…”