Al. Vancoller et al., LINKING RIPARIAN VEGETATION TYPES AND FLUVIAL GEOMORPHOLOGY ALONG THESABIE RIVER WITHIN THE KRUGER-NATIONAL-PARK, SOUTH-AFRICA, African journal of ecology, 35(3), 1997, pp. 194-212
Vegetation types were studied in relation to the fluvial geomorphology
along the mixed bedrock-alluvial Sabie River within the Kruger Nation
al Park, Mpumalanga, South Africa. Six vegetation types were identifie
d using TWINSPAN analysis, namely: Phragmites mauritianus, Phyllanthus
reticulatus, Breonadia salicina, Combretum erythrophyllum, Diospyros
mespiliformis and Spirostachys africana vegetation types. Spirostachys
africana and Diospyros mespiliformis vegetation types were found to o
ccur predominantly on the stable, infrequently flooded macro-channel b
anks, while the remaining four vegetation types were found almost excl
usively along the more geomorphically and hydrogically dynamic macro-c
hannel floor. The degree of bedrock or alluvial influence was identifi
ed as being an integral factor in the distribution of the four macro-c
hannel floor vegetation types at both the morphological unit and the c
hannel type scale. The geomorphological continuum from the bedrock inf
luenced bedrock anastomosing channel types, to mixed anastomosing and
pool-rapid channel types, to the fully alluvial braided channel types,
is reflected in the change in species composition from Breonadia sali
cina vegetation type, to Phyllanthus reticulatus and Phragmites amurit
ianus vegetation types, to Combretum erythrophyllum vegetation types,
respectively. Given the vegetation/alluvial geomorphology links establ
ished, changes in vegetation composition are proposed in response to s
cenarios of geomorphological change as a result of a progressive sedim
entation.