Post on 03-Feb-2022
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Plant-pollinator network diversity in calcareous grasslands
Natasha de Manincor
University of Lille
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Calcareous grasslands
• Semi-natural habitats
• High diversity of both plant and insect species, variety of rare species
• High proportion entomophilous species
• Greatest amount of floral resources, i.e. plant nectar per unit area
WallisDeVries et al. 2002; Butaye et al. 2005; Baude et al. 2016
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Calcareous grasslands
Ecological function → Pollination
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Pollinators and insects decline
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
New challenge for Natural reserves
Preserving species interactionsConservation of the ecological function
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Study goals
• Species diversity
• Interactions diversity
• Characterize plant-pollinator networks
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Plant-pollinator networks
Social network
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Direct interaction
Indirect interactions
Indirect interactions
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Material and Methods• Fieldwork sessions:
from April to October (once a month)
for two consecutives years (2016 and 2017 )
• Three regions, 6 calcareous grasslands (CEN NPdC, Picardie and Normandie)
Hauts-de-France
Normandie
Occitanie
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Les Falaises(Giverny)
Chateau Gaillard(Les Andelys)
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
BOTANIC INVENTORY
POLLINATORSAMPLING
Wild bees Hoverflies
Flowering species
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
BOTANIC INVENTORY
Flowering species
POLLEN ATLAS
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Plant-pollinator interactions
Pollinator diversity
ACTIVESAMPLING
PASSIVESAMPLING
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Pollen Scattered
Specializedstructures
Pollen Collected
Nest
Pollination event
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Insect preparation and taxonomic identification at the species level by experts (C. Vanappelghem, D. Genoud, M. Aubertand many others)
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Results
20162017
Hauts-de-FranceNormandieOccitanie
94 species92 species221 species
288 plant species overall (2016 and 2017)
Only 9% of species were shared among the 3 regions
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
15702 sampled insects overall
20162017
318 bee species (33% of the French bee fauna)
109 hoverfly species (20% of the French hoverfly fauna)
166 species221 species340 species
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Hauts-de-France
Normandie
Occitanie
2016 2017
Differences in species richness among regions & along the season
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Important species turnover along the season, with most species showing short phenologies
Hauts-de-France
Normandie
Occitanie
Nb of months occurence
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
timeApril October
Anacamptispyramidalis
Bombuslapidarius
Andrenadorsata
Euphorbiaesula
Hieraciumpilosella
Panurguscalcaratus
Picrishieracioides
Lasioglossuminterruptum
Anthericumramosum
Osmiarufohirta
Campanularotundifolia
Chelostomacampanularum
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Bombuspratorum
Andrenagravida
Helianthemumapenninum
Polygalacalcarea
Helianthemumoelandicum
Hieraciumpilosella
It is therefore essential not only to focus on the rare species, but to consider the entire community and the interactions among species.
Anacamptis pyramidalis
Protected species
Lasioglossuminterruptum
Anthericumramosum
Centaureascabiosa
Ononisnatrix
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Château Gaillard : a case of study• Nb insect species: 178
• Nb plant species: 77
• Nb recorded interactions: 1724
• Insect species higher nb interactions (> 100):• Lasioglossum interruptum (n = 183)• Lasioglossum morio (n = 200)• Bombus pascuorum (n = 210)• Bombus lapidarius (n = 213)
• Plant species higher nb interactions (> 100):• Centaurea scabiosa (n = 109)• Helianthemum apenninum (n = 118)• Leontodon hispidus (n = 131)• Hieracium pilosella (n = 160)• Anthericum ramosum (n = 214)• Scabiosa columbaria (n = 230)
Helianthemumapenninum
Anthericumramosum
Bombuslapidarius
Lasioglossuminterruptum
Generalist speciesLong phenology
Short phenology
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
• Flowering period during the richest months / year
• Short phenology (3 months)• High abundance
• Early phenology• Short phenology
(2 months)• Important
resource for many (early) pollinators (25 different species)
April October
Helianthemumapenninum
Anthericumramosum
Scabiosacolumbaria
Leontodonhispidus
• Longer phenology(from June untilOctober)
• Important at the end of the season(responsable for halfof interactions)
Low priority No priority No priorityPDG 2013-2017
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
• Early phenology• Long phenology (from April to August)• Most visited plant species in Chateau Gaillard: 37
different pollinator species
April October
No priority, no threaten species, no patrimonial interestPDG 2013-2017
Hieraciumpilosella
Andrena humilisOligolectic speciesSolitary speciesUnivoltine
Colletes similisOligolectic speciesSolitary speciesUnivoltine
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Perspectives• Management plans need to be adapted both to
maintain biodiversity and ecological functions;
• Management plans need to be adapted followingthe species phenology. For example: an earlygrazing or in the richest months can compromise access to resources for pollinators;
• It is also necessary to preserve the “common species” that are important for pollinators and indirectly (via indirect interactions) for the maintenance of rare species
European
workshop
Atlantic biogeographicalcalcareous grasslands
September 18th – 19th 2019
Rouen, France
Thanks for your attention
natasha.de-manincor@univ-lille.fr
Thanks also to all the bees and hoverflies that offered their lives for the good of Science!
Thanks also to Emmanuel Vochelet and CEN Normandie for the access to the study sites