English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
 
 
DownloadE-Mail
  The impact of livestock grazing on plant diversity: an analysis across dryland ecosystems and scales in southern Africa

Hanke, W., Böhner, J., Dreber, N., Juergens, N., Schmiedel, U., Wesuls, D., et al. (2014). The impact of livestock grazing on plant diversity: an analysis across dryland ecosystems and scales in southern Africa. Ecological Applications, 24, 1188-1203. doi:10.1890/13-0377.1.

Item is

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Hanke, Wiebke, Author
Böhner, Jürgen1, Author           
Dreber, Niels, Author
Juergens, Norbert, Author
Schmiedel, Ute, Author
Wesuls, Dirk, Author
Dengler, Juergen, Author
Affiliations:
1B 2 - Land Use and Land Cover Change, Research Area B: Climate Manifestations and Impacts, The CliSAP Cluster of Excellence, External Organizations, ou_1863482              

Content

show
hide
Free keywords: FUNCTIONAL DIVERSITY; SPECIES-DIVERSITY; SUCCULENT KAROO; SPATIOTEMPORAL VARIATION; HERBACEOUS VEGETATION; COMMUNITY STRUCTURE; WATERING POINTS; TRAIT RESPONSES; SEED BANKS; NE SPAINalpha diversity; beta diversity; biodiversity; disturbance; evenness; fence-line contrast; functional diversity; Nama Karoo; rangeland degradation; richness; stability; Succulent Karoo;
 Abstract: A general understanding of grazing effects on plant diversity in drylands is still missing, despite an extensive theoretical background. Cross-biome syntheses are hindered by the fact that the outcomes of disturbance studies are strongly affected by the choice of diversity measures, and the spatial and temporal scales of measurements. The aim of this study is to overcome these weaknesses by applying a wide range of diversity measures to a data set derived from identical sampling in three distinct ecosystems. We analyzed three fence-line contrasts (heavier vs. lighter grazing intensity), representing different degrees of aridity (from arid to semiarid) and precipitation regimes (summer rain vs. winter rain) in southern Africa. We tested the impact of grazing intensity on multiple aspects of plant diversity (species and functional group level, richness and evenness components, alpha and beta diversity, and composition) at two spatial scales, and for both 5-yr means and interannual variability. Heavier grazing reduced total plant cover and substantially altered the species and functional composition at all sites. However, a significant decrease in species alpha diversity was detected at only one of the three sites. By contrast, alpha diversity of plant functional groups responded consistently across ecosystems and scales, with a significant decrease at heavier grazing intensity. The cover-based measures of functional group diversity responded more sensitively and more consistently than functional group richness. Beta diversity of species and functional types increased under heavier grazing, showing that at larger scales, the heterogeneity of the community composition and the functional structure were increased. Heavier grazing mostly increased interannual variability of alpha diversity, while effects on beta diversity and cover were inconsistent. Our results suggest that species diversity alone may not adequately reflect the shifts in vegetation structure that occur in response to increased grazing intensity in the dryland biomes of southern Africa. Compositional and structural changes of the vegetation are better reflected by trait-based diversity measures. In particular, measures of plant functional diversity that include evenness represent a promising tool to detect and quantify disturbance effects on ecosystems.

Details

show
hide
Language(s): eng - English
 Dates: 2014
 Publication Status: Issued
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1890/13-0377.1
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Ecological Applications
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Tempe, AZ : Ecological Society of America
Pages: - Volume / Issue: 24 Sequence Number: - Start / End Page: 1188 - 1203 Identifier: ISSN: 1051-0761
CoNE: https://pure.mpg.de/cone/journals/resource/954925593483