Above-ground grazing affects floristic composition and modifies soil trophic interactions

R. Neilson, David Robinson, C. A. Marriott, C. M. Scrimgeour, D. Hamilton, J. Wishart, B. Boag, L. L. Handley

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

There are few data on the functional inter-relationships between above- and below-ground components of soil ecosystems. Here, we report changes in below-ground soil invertebrate trophic relationships (manifested as alterations in stable isotope natural abundances, delta C-13 and delta N-15) that arose in association with the removal of sheep grazing and from the resulting changes in above-ground floristic composition. Consequent to grazing removal, Lolium perenne L. (perennial rye-grass) was replaced as the dominant plant species in ungrazed treatments by Ranunculus repens L. (creeping buttercup), a species with more C-13-enriched foliage. Consequently, all invertebrate functional groups studied, but not whole soil, were more C-13-enriched in ungrazed treatments. Earthworms (detritivore) from grazed treatments were significantly N-15-enriched compared with earthworms from ungrazed treatments. In contrast, slug (herbivore) delta N-15 exhibited no treatment effect. Reasons for this are unclear but may be related to the effects of above-ground grazing on the composition of below-ground microbial/microfaunal communities. Omnivores/carnivores (beetles and spiders), were more N-15-enriched than primary producers in the grazed than in the ungrazed treatments (6 vs. 4parts per thousand) suggesting a longer below-ground foodchain in the grazed plots. The cessation of fertilizer application had no comparable effects on below-ground trophic relationships. (C) 2002 Elsevier Science Ltd. All rights reserved.

Original languageEnglish
Pages (from-to)1507-1512
Number of pages5
JournalSoil Biology and Biochemistry
Volume34
DOIs
Publication statusPublished - 2002

Keywords

  • ecosystem function
  • grazing
  • soil ecosystems
  • stable isotopes
  • trophic interactions
  • N-15 NATURAL-ABUNDANCE
  • UPLAND GRASSLAND SOIL
  • ECOSYSTEM PROPERTIES
  • WATER AVAILABILITY
  • CROPPING SYSTEMS
  • STABLE ISOTOPES
  • FOOD-WEB
  • PLANT
  • EARTHWORMS
  • MANAGEMENT

Cite this

Neilson, R., Robinson, D., Marriott, C. A., Scrimgeour, C. M., Hamilton, D., Wishart, J., Boag, B., & Handley, L. L. (2002). Above-ground grazing affects floristic composition and modifies soil trophic interactions. Soil Biology and Biochemistry, 34, 1507-1512. https://doi.org/10.1016/S0038-0717(02)00122-0