Rangeland Ecology & Management

Get reliable science

Responses of grasshopper assemblages to long-term grazing management in a semi-arid African savanna
Author
Gebeyehu, Solomon
Samways, Michael J
Publisher
Agriculture, Ecosystems & Environment
Publication Year
2003
Body

A study on grasshopper assemblage response to seasonal grazing, rotational grazing, continuous resting and continuous grazing was undertaken in the eastern Karoo, South Africa. Rotationally-grazed sites supported the highest number and abundance of grasshopper species while continuously-grazed sites had the lowest. Spring-grazed and winter-grazed sites were the most similar, with continuously-rested sites being the next similar to these. Rotationally-grazed sites showed the least similarity to the other sites. There were clear groupings of sites and grasshopper species, with most species associated with rotationally-grazed sites. Continuously-grazed sites had a different grasshopper assemblage. The assemblages followed definite gradients of measured environmental variables. Rotationally-grazed sites occurred along gradients of increasing bare ground, while continuously-grazed and summer-grazed sites occurred along increasing gradients of shrub cover and soil temperature. Spring-grazed, autumn-grazed, winter-grazed and rotationally-grazed sites were characterized by high vegetation density. Grasshopper dominance differed between sites. Summer-grazed sites had high dominance of Pycnodictya flavipes (40%), winter-grazed sites of Pseudogmothela sp. (32%) The significance of variable grazing management systems for maintaining floral and grasshopper diversity is discussed. Rotational grazing in this arid system is most suited to maintaining plant and insect diversity.

Language
English
Resource Type
Text
Document Type
Journal Issue/Article
Journal Volume
95
Journal Number
no. 2-3
Journal Pages
613-622
Journal Name
Agriculture, Ecosystems & Environment
Keywords
seasonal grazing
rotational grazing
Karoo
grasshoppers
South Africa
plant production
insects
grazing
land use
rangelands
biodiversity
Africa