Specific edge effects in highly endangered Swartland Shale Renosterveld in the Cape Region
Date
2011
Journal Title
Journal ISSN
Volume Title
Publisher
Shrubland -- Cape Floristic Region -- South Africa
Abstract
The critically endangered Renosterveld shrubland
of the Cape Floristic Region in South Africa
is one of the most transformed vegetation types
in the world. The mostly small patches that
remain after the extensive fragmentation are
potentially vulnerable to edge effects and
therefore, information on the extent of edge
effects in this vegetation type is urgently
required for conservation planning. To provide
this information, we studied edge effects at two
sites in each of five larger fragments of Swartland
Shale Renosterveld near Cape Town surveying
the vegetation composition along three
10 m wide and 200 m long belt transects. There
was little indication of edge effects among the
dominant woody species. However, abundance
and/or species richness of the petaloid monocotyledonous
plants, which contribute a disproportionally
high fraction of the vegetation
type’s high biodiversity, as well as the ferns, had
a clear negative correlation with edge proximity.
For these taxa, effects did not level off at the
end of the transect at 200 m. This extent of
impact is much larger than those reported in
most other studies on edge effects among plants. In contrast, species indicative of high disturbance
levels generally decreased within the
first 30 m. Consequently, Swartland Shale Renosterveld
fragments would be likely to benefit
from being enlarged to over 400 m width, while
corridors or stepping stones should have a width
of over 60 m to minimize major edge effects.
Description
CITATION: Horn, A., Krug, C.B., Newton, I.P. & Eslter, K.J. 2011. Specific edge effects in highly endangered Swartland Shale Renosterveld in the Cape Region. Ecologia Meditteanea, 37(2):63-74.
The original publication is availalbe at https://dialnet.unirioja.es/servlet/revista?codigo=20365
The original publication is availalbe at https://dialnet.unirioja.es/servlet/revista?codigo=20365
Keywords
Conservation planning -- Western Cape -- South Africa
Citation
Horn, A., Krug, C.B., Newton, I.P. & Eslter, K.J. 2011. Specific edge effects in highly endangered Swartland Shale Renosterveld in the Cape Region. Ecologia Meditteanea, 37(2):63-74.