The influence of rainfall and grazing on the population and compositional response of some Savanna grasslands.
Date
1991
Authors
O'Connor, Timothy Gordon
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The study aimed to differentiate the effect of rainfall and grazing on
the compositional change of savanna grasslands, and to explain responses
in terms of the life history patterns of the main species, An extinction
prone perennial grass under heiry grazing was identified as a palatable,
obligate seed reproducer with low seed production and poor dispersal (e.g.
Themeda triandra and Reteropogon contortus), wnich could become extinct
if the established population and the seed bank were eliminated. Aristrida
species were expected to show the converse pattern. Grazing was
manipulated for three or five years, and rainfall for one year, on a
sandveld site, and two clay soil sites which supported the same species
in different amounts, respectively. (Abbreviation abstract)
Description
A thesis submitted to the Faculty of Science,
University of the Witwatersrand, Johannesburg,
in fulfilment of the requirements for the degree
of Doctor of Philosophy
Keywords
Vegetation dynamics., Grassland ecology., Plant communities., Grasslands -- Effect of rainfall on., Grasslands -- Effect of grazing on.