Abstract
Livestock grazing is a major driver of land-use change, causing significant biodiversity loss globally. Although the short-term effects of livestock grazing on individual species are well studied, a mechanistic understanding of the long-term, cascading impacts is lacking. We manipulated livestock densities using a unique, replicated upland experiment over a 10-year period and found significant effects of grazing treatment on plant and arthropod biomass; the number of Anthus pratensis breeding bird territories; the amplitude of Microtus agrestis population cycles and the activity of a top predator, Vulpes vulpes. Lower plant biomass as a result of higher stocking densities led to cascades across trophic levels, with fewer arthropods and small mammals, the latter affecting predator activity. Breeding bird territories were a function of arthropod abundance and vegetation structure heterogeneity. Our results provide a novel food-web analysis in a grazing experiment to provide a mechanistic understanding of how food-webs in upland ecosystems respond to long-term livestock grazing pressure, with consequences for management.
Original language | English |
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Pages (from-to) | 1-15 |
Number of pages | 15 |
Journal | Ecosphere |
Volume | 6 |
Issue number | 3 |
Early online date | 30 Mar 2015 |
DOIs | |
Publication status | Published - Mar 2015 |
Bibliographical note
ACKNOWLEDGMENTSWe thank The Woodland Trust, Scotland for permission to use the Glen Finglas Estate. Sally Burgess, Timothy Conner, Charlie Gardner, Ian Joyce,Fi Leckie, Elaine McEwan, Ruth Mitchell, Gabor Pozsgai, Gina Prior and others assisted with the collection and sorting of samples at different stages of the project. S. M. Redpath, R. J. Pakeman, P. Dennis and D. M. Evans designed the study; D. M. Evans, N.Villar, N. A. Littlewood, S. A. Evans and J. Skartveit collected the data; D. M. Evans and N. Villar analyzed the data; D. M. Evans and N. Villar co-wrote as joint-first authors the first draft of the manuscript, and all authors contributed substantially to revisions.
Keywords
- agro-ecosystems
- conservation
- grassland
- moorland
- population cycles
- trophic interactions
- vole populations
- alpine ecosystem
- trait responses
- farmland birds
- sheep
- management
- dynamics
- rodent
- productivity