In:
PLOS ONE, Public Library of Science (PLoS), Vol. 15, No. 12 ( 2020-12-17), p. e0237484-
Abstract:
Livestock grazing and non-native plant species affect rangeland habitats globally. These factors may have important effects on ecosystem services including pollination, yet, interactions between pollinators, grazing, and invasive plants are poorly understood. To address this, we tested the hypothesis that cattle grazing and site colonization by cheatgrass ( Bromus tectorum ) impact bee foraging and nesting habitats, and the biodiversity of wild bee communities, in a shortgrass prairie system. Bee nesting habitats (litter and wood cover) were marginally improved in non-grazed sites with low cheatgrass cover, though foraging habitat (floral cover and richness, bare soil) did not differ among cattle-grazed sites or non-grazed sites with low or high cheatgrass cover. However, floral cover was a good predictor of bee abundance and functional dispersion. Mean bee abundance, richness, diversity and functional diversity were significantly lower in cattle-grazed habitats than in non-grazed habitats. Differences in bee diversity among habitats were pronounced early in the growing season (May) but by late-season (August) these differences eroded as Melissodes spp. and Bombus spp. became more abundant at study sites. Fourth-corner analysis revealed that sites with high floral cover tended to support large, social, polylectic bees; sites with high grass cover tended to support oligolectic solitary bees. Both cattle-grazed sites and sites with high cheatgrass cover were associated with lower abundances of above-ground nesting bees but higher abundance of below-ground nesters than non-grazed sites with low cheatgrass cover. We conclude that high cheatgrass cover is not associated with reduced bee biodiversity or abundance, but cattle grazing was negatively associated with bee abundances and altered species composition. Although floral cover is an important predictor of bee assemblages, this was not impacted by cattle grazing and our study suggests that cattle likely impact bee communities through effects other than those mediated by forbs, including soil disturbance or nest destruction. Efforts aimed at pollinator conservation in prairie habitats should focus on managing cattle impacts early in the growing season to benefit sensitive bee species.
Type of Medium:
Online Resource
ISSN:
1932-6203
DOI:
10.1371/journal.pone.0237484
DOI:
10.1371/journal.pone.0237484.g001
DOI:
10.1371/journal.pone.0237484.g002
DOI:
10.1371/journal.pone.0237484.g003
DOI:
10.1371/journal.pone.0237484.g004
DOI:
10.1371/journal.pone.0237484.g005
DOI:
10.1371/journal.pone.0237484.t001
DOI:
10.1371/journal.pone.0237484.t002
DOI:
10.1371/journal.pone.0237484.t003
DOI:
10.1371/journal.pone.0237484.s001
DOI:
10.1371/journal.pone.0237484.s002
DOI:
10.1371/journal.pone.0237484.s003
DOI:
10.1371/journal.pone.0237484.s004
DOI:
10.1371/journal.pone.0237484.s005
DOI:
10.1371/journal.pone.0237484.s006
DOI:
10.1371/journal.pone.0237484.r001
DOI:
10.1371/journal.pone.0237484.r002
DOI:
10.1371/journal.pone.0237484.r003
DOI:
10.1371/journal.pone.0237484.r004
Language:
English
Publisher:
Public Library of Science (PLoS)
Publication Date:
2020
detail.hit.zdb_id:
2267670-3
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