Organic farming: biodiversity impacts can depend on dispersal characteristics and landscape context

Feber, Ruth E.; Johnson, Paul J.; Bell, James R.; Chamberlain, Dan E.; Firbank, Leslie G.; Fuller, Robert J.; Manley, Will; Mathews, Fiona; Norton, Lisa R. ORCID: https://orcid.org/0000-0002-1622-0281; Townsend, Martin; Mcdonald, David W.. 2015 Organic farming: biodiversity impacts can depend on dispersal characteristics and landscape context. PLoS ONE, 10 (8), e0135921. 20, pp. https://doi.org/10.1371/journal.pone.0135921

Before downloading, please read NORA policies.

Preview

Text N511554JA.pdf - Published Version Available under License Creative Commons Attribution 4.0. Download (808kB) | Preview

Abstract/Summary

Organic farming, a low intensity system, may offer benefits for a range of taxa, but what affects the extent of those benefits is imperfectly understood. We explored the effects of organic farming and landscape on the activity density and species density of spiders and carabid beetles, using a large sample of paired organic and conventional farms in the UK. Spider activity density and species density were influenced by both farming system and surrounding landscape. Hunting spiders, which tend to have lower dispersal capabilities, had higher activity density, and more species were captured, on organic compared to conventional farms. There was also evidence for an interaction, as the farming system effect was particularly marked in the cropped area before harvest and was more pronounced in complex landscapes (those with little arable land). There was no evidence for any effect of farming system or landscape on web-building spiders (which include the linyphiids, many of which have high dispersal capabilities). For carabid beetles, the farming system effects were inconsistent. Before harvest, higher activity densities were observed in the crops on organic farms compared with conventional farms. After harvest, no difference was detected in the cropped area, but more carabids were captured on conventional compared to organic boundaries. Carabids were more species-dense in complex landscapes, and farming system did not affect this. There was little evidence that non-cropped habitat differences explained the farming system effects for either spiders or carabid beetles. For spiders, the farming system effects in the cropped area were probably largely attributable to differences in crop management; reduced inputs of pesticides (herbicides and insecticides) and fertilisers are possible influences, and there was some evidence for an effect of non-crop plant species richness on hunting spider activity density. The benefits of organic farming may be greatest for taxa with lower dispersal abilities generally. The evidence for interactions among landscape and farming system in their effects on spiders highlights the importance of developing strategies for managing farmland at the landscape-scale for most effective conservation of biodiversity.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1371/journal.pone.0135921
UKCEH and CEH Sections/Science Areas:	Parr
ISSN:	1932-6203
Additional Information. Not used in RCUK Gateway to Research.:	Open Access paper - full text available via Official URL link.
NORA Subject Terms:	Ecology and Environment
Date made live:	02 Oct 2015 15:57 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/511554

Actions (login required)

View Item

Document Downloads

More statistics for this item...