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Change in relative abundance and species composition is probable, and indeed likely, for fynbos communities in the post disturbance environment (Kruger, 1983; Privett, 1998; Thuiller et al., 2007). Most studies, however, investigate the impacts of disturbance on fynbos assemblages in relation to natural disturbance events such as fire, whereas wildflower farming practices manifest as anthropogenic disturbances that are less commonly studied. How likely then is change, in fynbos composition and species persistence, in this unique post-disturbance environment? This thesis cannot ascertain a complete answer to this question but can remark considerably on the topic.

High cover of overstorey shrubs can potentially increase alpha diversity of the understorey (Vlok and Yeaton, 2000). Also, species composition prior to a disturbance event will ultimately determine post- disturbance species composition (Hanes, 1971). However, altered structural composition in fynbos and associated lower species richness and diversity observations in treatment sites (broadcast sown and shallow ploughed) (Chapter 3) do not suggest a considerable increase in plant diversity in the near future. This is supported by Davis (1990) who reported that ploughing reduced species richness and plant diversity in mountain fynbos. Whether or not this phenomenon extends over a longer temporal scale has not been investigated and must be explored in the future (see section 5 this chapter). Therefore, one could (at least in the short term) argue that mechanical disturbance methods used in wildflower farming (like shallow ploughing) will compromise plant diversity conservation. Heydenrych (1999) also suggested that wildflower farming practices could establish monocultures of commercial species and results presented in this study strongly correspond with the former research findings (Davis, 1990) and supposition (Heydenrych, 1999). Some results from a previous study by Joubert et al. (2009) are in direct contradiction to the latter statement and Chapter 3 outlines possible reasons for deviation.

Wildflower farmers, farming with natural vegetation, rely directly on fynbos diversity to sustain a livelihood (Conradie, 2009a). Therefore it is important to maintain some degree of plant diversity within wildflower vegetation. Heydenrych (1999) recorded a total of 71 fynbos species used by the entire wildflower market (includes naturally occurring and cultivated species) on the Agulhas Plain. Fifteen species recorded in the vegetation survey (Chapter 4) are currently popular and commercially harvested products (Conradie, 2009a). Some species are commercially more important (Protea

compacta and Leucadendron platyspermum) than others and can be intensively cultivated (i.e. orchard- like cultivation). However, fynbos bouquets hardly consist of a single commercial species (Plate 3) and many species, especially filler material (used to assemble fynbos bouquets), cannot be cultivated (due to resistance to growing in a controlled environment, pests, parasites etc.). As a result, „filler‟ species will continuously be harvested from natural vegetation (Cowling, 1989; Davis, 1992; Conradie and Knoesen, 2009). Moreover, the establishment of cultivated plantations is expensive and labour intensive which often favours sustained harvesting from natural vegetation (Greyling and Davis, 1989). The vegetation survey suggests that, although some commercial species increase in cover (Protea compacta and Leucadendron platyspermum), a result of broadcast sowing and/or shallow ploughing, other commercially important species (Berzelia lanuginosa and Berzelia abrotanoides) are simultaneously affected by showing reduced cover in treatment sites. This reduces the profusion of wildflower products available to the farmer and must surely rouse concern. Overshadowing this effect, however, is the fact that most commercial species seem unaffected (see Chapter 4). Moreover, this investigation showed that it is not only commercial species that are favoured by wildflower farming practices but also other fynbos species (e.g. Passerina corymbosa, Cliffortia strica) that have no commercial value to the wildflower farmer (Conradie, 2009a).

Four species that have been used in broadcast sowing (P. compacta, L. platyspermum, L. coniferum, A. umbellata) (Table 2.4) have a so-called „rarity status‟ (other than „least concern‟) according to the Red List of South African Plants (Raimondo et al., 2009) and are therefore species of conservation priority. Furthermore, three of the four species (excluding A. umbellata) are known to be widely cultivated (marginally and intensively) on the Agulhas Plain (Heydenrych, 1999). From this an interesting issue arises, i.e. that these species are artificially favoured, in terms of increased cover, in wildflower farming practices (see Chapter 4). The conflict in this is; that a species of „conservation concern‟ is benefitting from wildflower farming but the fynbos community is suffering (in terms of structure, species richness, plant diversity, plant family and dominant species composition). Genetic contamination is also a conservation issue in need of research attention (Littlejohn, 2002; Whelan et al., 2006; also see section 5). As a final note with no perceptible answer, one also has to ask the question; “Why are species with a particular „rarity‟ status (Near Threatened (NT) and Vulnerable (VU) (sensu Raimondo et al., 2009)) harvested from natural vegetation”?

Heydenrych (1999) reported that a total area of 89 767 ha indigenous vegetation is used exclusively for fynbos wildflowers of which Acid Sand Proteoid Fynbos25 is the dominant vegetation type. As a consequence approximately 3000 ha on the Agulhas Plain has been mechanically disturbed (scarified (i.e. worked lightly with a toothed implement) and ploughed) for purposes of fynbos wildflower farming. This figure includes both „marginally cultivated‟ and „intensively cultivated‟ fynbos (see Chapter 1 for definitions) where „marginally cultivated‟ areas include; broadcast sowing (1962 ha) and strip ploughing (913 ha). „Intensively cultivated‟ fynbos constituted 93 ha (Heydenrych, 1999). Although a distinction is made in wildflower farming between cultivation intensities (marginal versus intensive) much remains in a „grey area‟ regarding types of farming practices and exact application. The „broadcast sowing‟ in the above figure also includes other farming practices (such as burning and shallow ploughing) that contributes to the disturbance event but it is not always clear how individuals (researchers and farmers) define particular events. This can significantly diminish the accuracy of survey/management information. Furthermore, it is significant to note that although sandstone fynbos is not currently a vegetation type of conservation priority (a result of large expanse on the Agulhas Plain and few threatened plant species restricted to this vegetation (Mucina and Rutherford, 2006)), plant diversity conservation in context of wildflower farming is an emerging issue, especially considering that 55 of the 71 species harvested on the Agulhas Plain are derived from sandstone fynbos vegetation (Heydenrych, 1999).