The Vegetation of the Kroonstad Area, Orange Free State I: Vlei and Bottomland Communities
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S.AfrJ.Bot., 1991, 57(4): 213 - 219 213 The vegetation of the Kroonstad area, Orange Free State I: vlei and bottomland communities M.S. Kooij,* J.e. Scheepers,t G.J. Bredenkamp* and G.K. Theron* "Department of Botany, University of Pretoria, Pretoria, 0002 Republic of South Africa tGrassland Research Centre, Private Bag X05, Lynne East, 0039 Republic of South Africa Accepted 7 May 1991 Vegetation data from the Kroonstad area were analysed. The entire data set (235 releves) was subdivided into two tabulation subsets by TWINSPAN classification, followed by Braun-Blanquet procedures. One subset, representing the vlei and bottomland vegetation, was classified further by Braun-Blanquet procedures. Eight communities, grouped into four major communities, were identified and described. The results can be inte grated with existing phytosociological classifications of the north-western Orange Free State. 'n Ontleding van plantegroeidata vanaf die Kroonstad omgewing word aangebied. Die totale datastel (235 releves) is in twee subdatastelle verdeel, met behulp van 'n TWINSPAN klassifikasie, gevolg deur die Braun-Blanquet prosedure. Een subdatastel wat die plantegroei van die vleie en laaglande verteenwoordig, is verder deur middel van die Braun-Blanquet prosedure geklassifiseer. Agt plantgemeenskappe, wat vier hoofgemeenskappe verteenwoordig, is onderskei en bespreek. Die resultate kan ge'integreer word met be staande fitososiologiese klassifikasies van die noord-westelike Oranje-Vrystaat. Keywords: Braun-Blanquet, classification, Grassland Biome, plant communities. Introduction land Biome of the north-western Orange Free State (Figure Scheepers (1975) classified the vegetation of the Kroonstad 1). This area comprises approximately 625000 ha. A de area by association analysis, a monothetic divisive classifi scription of the physical environment of the area was given cation technique (Gauch 1982). Association analysis is by Scheepers (1975), and is therefore not presented here. based on the successive subdivision of vegetation samples into two groups according to the presence or absence of a Methods single species. This process is repeated a number of times in In the semi-detailed ecological survey of the vegetation in order to yield a hierarchy. The dividing species are those the Kroonstad area, 235 releves were compiled using a that have the maximum ability to separate one group or stratified random sampling strategy (Schccpers 1975). This association of species from another association, implying the inventory was intended to provide the basis for rational land maximum sum of chi-squared values with all other species. use, larger scale planning and realization of the agricultural Although Scheepers (1975) derived ecologically interpret potential of the Highveld Region (Scheepers 1975). A 16-m2 able vegetation types from the results of the association quadrat was used and cover abundance according to the analysis, reconciliation of this classification with the standard Braun-Blanquet scale (Mueller-Dombois & Ellen comprehensive phytosociological classification of the north berg 1974) of all species present was recorded. In the pres western Orange Free State (Kooij, Bredenkamp & Theron ent study, these data were classified by means of a Two 1990a - d) is difficult, if not impossible, owing to major Way Indicator Species Analysis (TwINSPAN) (Hill 1979) and differences in the procedures and algorithms applied. Fur the resulting classification was refmed by means of the thermore, Coetzee and Werger (1975) showed that a poly Braun-Blanquet procedure (Table 1). This procedure was thetic Braun-BIanquet analysis of floristic data results in shown to be effective by Behr and Bredenkamp (1988), ecologically more reliable vegetation classes. Although the Bredenkamp et al. (1989) and Kooij et al. (1990a - d). association analysis algorithm utilizes only presence/absence Taxon names conform to those of Gibbs-Russell et al. data, Scheepers' s original data set comprised total floristic (1985 & 1987). composition with Braun-Blanquet cover abundance values for all identifiable species in the sample plots. In order to Results utilize all existing compatible data in a phytosociological Classification synthesis of the north-western Orange Free State, a reclassi On the basis of the major (first-level) division obtained by fication of Scheepers's data by Braun-Blanquet procedures the above procedure, the entire phytosociological table was was necessary. In this report the classification and descrip divided into two smaller tables, one containing 42 releves tion of the hygrophilous vlei and bottomland vegetation of (Table 1), representing the vlei and bottomland commun the Kroonstad area are presented. ities, and the other containing 193 releves (Kooij, Schee pers, Bredenkamp & Theron 1991), representing grassland Study area communities. A comparison of the classification of the total The study area is situated between 27°00' and 2r15'S data set (Scheepers 1975) by association analysis and the latitude and 27°30' and 2r45'E longitude, in the Grass- present procedure is given in Table 2. The allocation of 214 S.-Afr.Tydskr.Plantk.• 199I.57(4) 26·00' 27·00' Nt Legend: A -land type A e [ill Aim n -land type ncO nd LJill D -land type Dbb2J DcD IIills and ridges na fZ1 Fb~ lbG Scheepers' s study area 1-.~-' Figure 1 A map indicating the location of Scheepers's study area (1975) in the north-western Orange Free State (after Land Type Survey Staff 1984). Table 1 A phyttosociological table of the vlei and borromland communities of the Kroon- stad area described by Scheepers (1975) Conmunlties 2 3 4 1. 1 1.2 1.3 3.1 3.2 3.1.1 0111 12 001 00 01 01111211 21111112110111102 8668 70 415 55 97 80468065 0011 9678 32 741 19 47 06899980703781590 0604 81891186 04089443626526236 1199 Species group A 1 1 1 1 1 1 1 1 1 1 Dip/achne rusca 1 1 1 1 1 1 1 Senecio burche//ii 124541 1 1 1 1 1 Stachys hyssOpoirtes 1 2 11 1 1 1 + 1 1 Crinum bu/bispermum 1+ 2 12 1 1 1 1++ 1 1 31 11 1 1 1 1 1 Species group B 1 1 1 1 1 1 1 1 1 1 1 1 1 1 £ragrostis plana 1 1 1 1 1 1 1 Calium capense 1 21331 11 1 + 1 1 Senecio inornatus 1 11 1 1 1 +1 1 Imperata cy/ indrica 1 13 1 1 1 1 1 1 12 1 1 1 1 1 Species group C 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Hemarchria a/Cissima 1 1 1 1 1 1 1 Equlsetum ramosissimum 1 1 12+11 1 1 1 Oenothera indecorus 1 1 11+21 1 1 1 Po/ygonum / apachiro/ ium 1 1 1+++1 1 1 1 Verbena orricinalis 1 1 1 ++1 1 1 1 Cyperus denudatus 1 12 1 ++1 1 + 1 1 1 1 1 41 1 1 1 1 1 S.AfrJ.Bot..1991, 57(4) 215 Table 1 (continued) I I I Spec ies group D I I I I I I I Echinochloa holubii 212 1+++ I I Cyperus longus 1+ ++ + I I I I Species group E I I I I Andropogon appendiculstus 3 121 I Scab/osa columbaria 21 I I Berkheya radula 11 I I Haplocarpha scaposa 1+1 I Falkia oblonga ++ I I Species group F I I Protasparagus laricinus 3413534253 +2232+12224+ 1++ Acacia karroo 2 42113543342 +52232 242+22 Teucrium triFidum + I +4 211 1+ 2+ + I I Species group G I I I I Melica decumbens 2 11331213 I May tenus heterophylla 221 22 I I 21 I + I Delosperma sutherlandii + Delospera herbeum 13 2 3+ I Diospyros Iycioides 331+2 I Pentarrhinum insipidum + 11 1 I Rhus pyroides 3 I 2 I I I Spec I es group H I I I I Celtis aFricana 31 I I Clematis brachiata 131 I Ziziphus mucronata 251 I Achyranthes aspera +11 I Ehrharta erecta 3 I I Lycium oxycarpum I 31 I Coccinia sessifolia 3 I 1 I Antizoma angustifol ia I I Species group I I 1+++++12++ + ++1 I + I Corchorus asplenifolius + + 2 ++1 11+1 2+ 2+21 I Eragrostis chloromelas +12+ 12 + 11 I 1 + I Aristida congesta 12 +1+ + Sporobolus ioclados 2 2 223 + + 2++2 +11 211 Eragrostis barbinodis +2+ +2 + I + Indigofera alternans + + + 2+ ++ +11 Eragrostis species I + Anthericum fasciculatum + +++++ + + ++ ++ + +1 Hermannia coccocarpa ++ I + Digitaria argyrograpta 22+2 + ++ + + ++ I Aptosimum procumbens I I Species group J I + 2+ +12+22+12++ 21++21+ Felicia muricata +++ I 1 +++2+1 1 +++++ 1+ Blepharis integriFolia 1 + 2 122 2 1 + 1 1 1+ Eragrostis obtusa + 1+++1+ +2 + 1 21 CYlllbopogon plurinodis ++ 1+ + 1++ +11 Halarrida densirlora I I I I Species group K I I Panicum coloratum 1+4123213213+12213+ 233212 ++ +1 411342 3+1 2+ +2213 +21 + 111 ++1 Atriplex semibaccata + +++ 1+111+++1++ +++++1+ + I Hibiscus pusillus I Cynodon hirsutus +1 I 13 31+ 1+3321 24+ 1 12134331 I I +1 I 312+2 233+++2 221 112 Pentzia globosa +1++ + I ++ +++ ++ +++++ I + Albuca setosa I I Eragrostis lehmanniana I I + 11+121 11 1 12 2 I 21 I I ++1 + I ++ + + + + 1+ Talinum cafFrum + + + 1+ + +1 1+ Cyperus usitatus I I I I I I Spec I es group L I I I I I I I I Cynodon dactylon ++ 12 333 1+ 11 3 21+ 111 3 3 1 1 1 I 3 Themeda triandra 2 24 2 122131221 2 1+ +21+1 2+ + + 1+ 2 + +1 Digitaria eriantha I I Species group M I Eragrostis curvula + + + I + ++ + + I Crabbea hirsuta +1 + Trachyandra aspera ++ + Convolvulus sagittatus + + + 1 I I 1 + + 12 I Pentzia calcarea +1 + +1 Sporobolus Fimbriatus + 2 + + + + +++ +1 I Moraea thomsoni i + + I +1 Portulaca quadrifida ++ + Eragrostis superba + 1 32 1 I + I Setaria Flabellata + 211 + 1 I I + + I + ++1 Ceigeria aspera + + 1+ Cazania krebsiana I + 1++ I Pterodiscus speclosus 1+ Scilla species + I + + Heteropogon contortus I + + + I Solanum supinum I ++ + I Pollichia calilpestris +1 + I 1 Barleria macrostegia 1++ + I + I + 2 I Lycium species +1+ Ruschia hamata + I CO/flmicarpus pentandrus + I I + Commelina aFricana +1 ++ I Species with an occurrence of '" 2 have been omitted.