A descrição dos padrões de acumulação de espécies com o aumento da área amostrada, através da curva de acumulação de espécies, tem diversas aplicações no estudo de comunidades vegetais. Porém o uso dessa relação como uma ferramenta para determinar a suficiência amostral em estudos fitossociológicos apresenta problemas metodológicos, como a arbitrariedade da ordem de entrada das unidades amostrais na construção da curva e a pressuposição de que um patamar será obtido no ponto em que o aumento da área amostrada não acrescentar novas espécies à amostra; e também problemas relacionados ao conceito de comunidade vegetal utilizado, que é considerada como uma entidade espacialmente discreta com composição de espécies fixa e definida. Em florestas tropicais a definição desses limites é dificultada pela alta riqueza de espécies e pela falta de estabilização da curva mesmo com grandes tamanhos de amostra. Utilizando dados de três formações florestais tropicais, foram obtidas curvas médias de acumulação de espécies e seus intervalos de confiança empíricos através de procedimentos de aleatorização, que enfatizaram o caráter assintótico da curva e evidenciaram a ausência de um ponto de inflexão para a determinação objetiva de um tamanho ótimo de amostra. Entretanto, o uso dos padrões de acumulação de espécies em estudos comparativos, seja em formações diferentes ou locais dentro de uma mesma formação, mostrou ser mais informativo. A análise das variações das estimativas de riqueza e do padrão de acumulação de espécies com tamanhos crescentes de amostra indicam que é possível identificar níveis de amostragem que permitem a distinção e a comparação entre locais. Por fim, considerando as limitações das medidas tradicionais de diversidade, como a dependência do esforço amostral, foram utilizados os índices de diversidade e distinção taxonômica para caracterizar e comparar a diversidade das diferentes formações estudadas. Além da vantagem de incorporar as diferenças taxonômicas entre as espécies à estimativa de diversidade, esses índices ainda apresentaram independência do esforço amostral e menor variabilidade, permitindo sua utilização na comparação entre áreas que tenham sido amostradas com diferentes intensidades. / The description of species accumulation patterns with the increase of sampled area using the species accumulation curve has many applications to plant community studies. The use of this relation as a tool to determine the sampling sufficiency in phytosociological studies, therefore, shows methodological problems such as the arbitrariness in the order of sampling units for the curve construction and the assumption that this curve tend to a flat line with the increase of sampled area. Another constraint is the plant community concept adopted, where the plant community is saw like a spatially discrete entity with fixed species composition. In tropical forests, the identification of communities boundaries is particularly difficult and, due to their high species richness, the species accumulation curves do not become flat, even with large sample sizes. Data from a sample of 5,74ha in three tropical forests showed a mean species accumulation curves, with empiric confidence intervals obtained by randomization procedures, which emphasized the asymptotical character of the curve. The curve also stressed the absence of a inflection point and indicated that it is not possible to objectively define a optimum sample size. Therefore the use of species accumulation patterns is more informative in comparative studies, either within or between plant formations, than in the description of a given individual study area. The analysis of the variations in richness estimates and species accumulation patterns with increasing sample sizes indicated that is possible to identify optimal sampling sizes in the comparison of different forest areas that allows to distinguish them. Finally, considering the limitations of traditional diversity measures, such as sampling effort dependency, diversity and distinctness taxonomic indexes were used to characterize and compare the diversity of the three different plant formations. Besides the advantage of incorporating the taxonomic differences among species, these indexes showed independence of sampling sizes and had estimates of low variability, which allows their utilization in comparisons of areas sampled with different intensities.

In 1530, a German physician named Otto Brunfels published an herbal entitled Herbarum Vivae Eicones (Living Images of Herbs). In it, he planned to map the names of medicinal herbs known in and native to Germany onto their Greek and Latin names. Brunfels’ audience included fellow physicians and in order to assist with the identification of the herbs in his book, his publisher employed a woodcut artist to produce realistic images of them, a novelty in the genre of printed herbals. Over time, Brunfels’ work was superseded by 16th-century botanists and his legacy was relegated to the illustrations of his herbs, while his contributions to the naming and description of them were dismissed as unoriginal. However, a closer examination reveals Brunfels’ herbal as a transitional text bridging the gap between the herbal tradition and the development of the science of botany. In addition to citing Pliny the Elder as his primary authoritative influence, Brunfels also references a number of 15th-century Italian humanist scholars who were neither botanists nor physicians, but who were known for their critiques of the early printed editions of Pliny’s Historia Naturalis and even of Pliny himself as a natural history authority. Thus, Brunfels’ herbal is tied to the manuscript and printing history of Pliny and to humanist attempts to correct and stabilize his text. Moreover, in the course of his work, Brunfels encountered a number of herbs that were known to him, but whose Latin and Greek nomenclature he could not accurately identify. As a result, he was forced to describe in his own words, in original Latin, these herbae nudae with German nomenclature but with unknown Greek and Latin names. In addition, Brunfels encounters considerable disagreement among the ancient authorities about the naming and classification of other herbs and he is again forced to insert his own opinion, which he calls iudicium nostrum. I argue that Brunfels’ original Latin is a very early example of what would eventually become formal botanical Latin. Brunfels’ herbal is situated in such a way that it looks backward whilst simultaneously looking forward. It is an object of reception, appropriating terminology and methods from Pliny the Elder and from the humanist scholars who debated the quality of the printed editions of his work and the accuracy of the information provided in it. It is simultaneously the subject of reception, demonstrating a halting, hesitant vocabulary and style of Latinity that would eventually come to be identified with botany as a discipline. Chapter 1 addresses Pliny’s ideas of what constitutes knowledge (cognitio) about plants in the Historia Naturalis, via his arguments against improper nomenclature (nomina nuda) and the alignment of herbal medicine with magic (magicae herbae). Pliny’s advocacy for proper methodology (experience over book learning) is also examined. Chapter 2 turns to the manuscript tradition of Pliny’s text and the first two printed editions, in 1469 and 1470, which were corrupt and resulted in an unstable, inaccurate text. In Chapter 3, the reactions of the Italian humanists to these early printed editions are considered, along with the transition from critiques of the editors and printers to debates about inaccuracies that can be traced to Pliny himself. Chapter 4 turns to Otto Brunfels and traces his reliance on Pliny as well as on the Italian humanists, especially Ermolao Barbaro, who claimed to “heal” the errors in Pliny and stabilized his text. Brunfels’ original descriptions of herbs are also discussed. In the conclusion, Brunfels’ work is compared with that of botanists who postdated him, including Leonhard Fuchs, Kaspar Bauhin, and Karl Linnaeus.

MESMEG / Department of Ecology and Resource Management / Invasive alien plants refer to plant species that show a tendency to escape from human control, go beyond the intended physical boundaries and cause environmental damage. The issue of letting the Invasive alien plant species grow and spread, with no attempts made to control the spread of the species beyond the limits of plantations, is not sustainable. All the attempted methods that the Department of Environmental Affairs used seemed to have failed in yielding the expected results. The main objective of the study was to determine the Wolkberg Working for Water programme’s level of success in terms of clearing invasive alien plant species. Wolkberg Project was used as a case study as it is one of the Working for Water Programme. The data were collected using random sampling methods on the worked areas, where work is in progress and those where no work has been done. Primary data were collected from land owners through field observations and questionnaires from the participants whilst secondary data were collected from the Department of Environmental Affairs. The study adopted a mixed methods approach which is both quantitative and qualitative. The data were analyzed using Statistical Package for the Social Sciences (SPSS) package. The research determined the level of success in terms of clearing invasive alien plant species, employment opportunities, tools/materials that have been used to clear the plants and the advice on the possible strategies that can be employed in the invasive alien plant species management. It was found out that the Invasive alien plant species require constant maintenance in order for them to be controlled. The Wolkberg project is mainly dominated by male workers compared to females. Each team comprised 3% underage workers. The study recommends that the project should make sure that the follow-ups are done at the correct time and stage. Looking at the statistics of males and females, the study revealed that transformation is not adhered to in this project. / NRF