Organic dairy farming: impacts on insect-flower interaction networks and pollination
Citation:
Power EF, Stout JC, Organic dairy farming: impacts on insect-flower interaction networks and pollination, Journal of Applied Ecology, 48, 3, 2011, 561-569Download Item:
Organic dairy farming- impacts on insect?flower interaction networks and pollination.pdf (Published (publisher's copy) - Peer Reviewed) 316.2Kb
Abstract:
1. Pollination interactions comprise a network of connections between ?owers and insect visitors.
They are crucial for reproductive success in many angiosperms but are threatened by intensive agricultural practices. Although less intensive approaches, including organic farming, could improve
farmland biodiversity, it is not clear whether or not these approaches enhance wild plant pollination
and the stability of insect??ower interaction networks.
2. We investigated the e?ects of organic vs. conventional farming on insect??ower interaction network size and structure, bee and hover?y diversity, and pollination in 10 pairs of organic and conventional dairy farms in the Republic of Ireland.
3. We found that insect??ower interaction networks on organic farms were larger and more asymmetrically structured than networks on conventional farms. Overall, however, networks contained
fewer taxa and niche overlap and plant ? animal ratios were relatively low compared with previously
documented insect??ower interaction networks. Organic farms did attract higher numbers of bees
partly because of higher ?oral abundances (mainly Trifolium sp.). Hover?y evenness was greater in
organic farms but neither abundance, richness nor evenness was related to ?oral abundance, suggesting organic farms provide additional resources for hover?ies. Pollination of Crataegus monogyna hawthorn was higher on organic farms, although pollen deposition was limited.
4. Synthesis and applications. Organic dairy farming can increase the size and alter the structure of
insect??ower interaction networks. However, network stability was not improved and all networks
(organic and conventional) were vulnerable because of their small size, low niche overlap and low
plant ? animal ratios. Nonetheless, organic farming provided more ?owers that attracted more
?ower visitors and improved pollination of C. monogyna. We suggest that strategic management of
important ?owers for pollinators in hedgerows and pastures should be endorsed in agri-environmental schemes. Sowing Trifolium spp., and allowing these plants to ?ower, could bene?t bees, but
more research into hover?y ecology is necessary before realistic conservation recommendations can
be made for this group. We conclude that organic farming, although not the solution in its present
form, can bene?t insect biodiversity, insect??ower interaction networks and insect-mediated pollination.
Sponsor
Grant Number
Teagasc
Author's Homepage:
http://people.tcd.ie/stoutjDescription:
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Author: Stout, Jane
Type of material:
Journal ArticleCollections:
Series/Report no:
Journal of Applied Ecology48
3
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Full text availableKeywords:
Botany, Pollination interactionsSubject (TCD):
Smart & Sustainable Planet , Biodiversity and Conservation , EcologyLicences: