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A research report submitted to the School of Social Sciences, Faculty of Humanities of the University of the Witwatersrand in partial fulfilment of the requirements for the degree of Master of Arts in History 04 May 2015 / This report analyzes the reasons behind the adoption of out growing schemes (sistemas canavieiros) by two Mozambican sugar companies, namely the Companhia do Buzi and the Açucareira de Moçambique as well as the impacts of the companies’ decision on the mills as well as on local communities. Analyzing the adoption of out growing schemes is relevant due to the fact that the Companhia do Buzi and the Açucareira de Moçambique were the only two out of ten Mozambican sugar companies to collaborate with out growers. All the out growers were Portuguese citizens or ‘civilized’ Africans. The report also analyses the reasons and the impacts of the collapse of those schemes in the early post-colonial period. The report argues that the mills adopted out growing schemes to face the long term shortage and increasing costs of African agricultural labour. This strategy solved their problems but left the out growers indebted and frustrated and local communities dispossessed. On the collapse of the out growing schemes, the report argues that it resulted from the increasing lack of economic feasibility of sugar cane growing, which was a result of economic crisis and the authorities’ hostility towards the out growers.

La déforestation effectuée dans l'optique d'une récolte de bois par l'industrie forestière ou afin d'augmenter la superficie des champs pour l'agriculture est en constante progression dans le monde et amène bien des problèmes environnementaux qui passent de la dégradation du sol, à la diminution de la biodiversité et aux changements climatiques. Il est donc urgent de prendre les mesures qui s'imposent pour contrer ce problème. Une des solutions préconisées actuellement est l'établissement de plantation d'arbres pour le bénéfice de la restauration du sol et de la production commerciale de bois. Ce type de plantation, en région tropicale, est principalement effectué en monoculture d'espèces d'arbres exotiques. Au Panama, en 2003, 89% des arbres en plantation provenaient de quelques genres exotiques seulement. Il y a donc à craindre quant à l'impact sur la biodiversité de ce type de reforestation en plus de ne pas toujours être bien adapté aux conditions du milieu. Il y a donc encore beaucoup de recherche à faire afin de trouver des solutions pertinentes à ces problématiques. Le projet PRORENA est une vaste étude cherchant, par la plantation d'espèces indigènes du Panama, à développer les connaissances touchant les espèces indigènes et leurs comportements en plantation. Le cadre de ce projet était particulièrement intéressant pour effectuer une étude portant sur la caractérisation de la croissance de ces espèces afin de mieux connaître leur autoécologie. L'apport de connaissances dans ce domaine permettra d'aider les propriétaires terriens à faire un choix plus éclairé des espèces les plus intéressantes pour la reforestation en fonction des objectifs visés. Ce projet de recherche visait donc à déterminer l'allométrie de l'allocation de la biomasse des arbres afin de mieux connaître l'autoécologie des espèces étudiées. Nous cherchions donc à mieux comprendre où se dirigent les ressources des arbres afin de faire un choix d'espèces éclairé lors de l'installation d'une nouvelle plantation et dans quelles proportions cette allocation change en fonction de la taille des individus, mais aussi en fonction de l'environnement (disponibilité des ressources, principalement l'eau) et en fonction des groupes fonctionnels. Pour ce faire, la récolte destructive de la biomasse aérienne des arbres a été effectuée pour 21 espèces d'arbres indigènes et 2 espèces exotiques. Cet échantillonnage nous a permis de comparer l'accumulation totale de biomasse aérienne entre les espèces, de même que de comparer la croissance entre deux sites présentant un gradient de précipitation et de richesse du sol. Ce projet a aussi permis de comparer la distribution de la biomasse entre les feuilles, les branches et le tronc en fonction des espèces et des sites et de déterminer si une relation allométrique simple peut être établie entre la biomasse totale et des mesures de taille comme le diamètre à la base de l'arbre et la hauteur. Par ailleurs, le manque d'informations sur les traits fonctionnels des espèces étudiées ne nous a pas permis d'aborder le sujet lors des analyses. Le taux de croissance des arbres varie grandement entre les espèces. Pour le tiers des espèces étudiées, l'accumulation de la biomasse aérienne est plus rapide au site plus humide et permet de penser que pour ces espèces, le choix du site semble important afin d'obtenir une croissance optimale. Certaines espèces indigènes performent aussi bien, sinon mieux que les espèces exotiques étudiées. Il est important de noter que l'allocation de la biomasse aux racines n'a pas été étudiée. Il est fort probable que la longueur de la saison sèche à Rio Hato influence positivement la croissance racinaire au détriment de la croissance aérienne et qu'il soit possible d'observer ces différences au niveau des traits étudiés. L'étude des relations entre les ratios longueur de la couronne:diamètre de la couronne et longueur de la couronne:hauteur totale et la taille soulignent l'importance de retirer cet effet afin de comparer les sites principalement à cause de la présence d'espèces aux tailles très variées. Lorsque ces ratios sont corrigés, nous observons un effet de l'espèce très prononcé. Par ailleurs, ces traits qui diffèrent entre les sites pour certaines espèces sont plus grands à Soberania. Finalement, il y a une relation importante entre le diamètre à la base de l'arbre, mesure simple de croissance, et la biomasse totale ce qui permet de déterminer l'accumulation de la biomasse aérienne pour n'importe quelle espèce d'arbre dans des conditions environnementales très différentes en termes de précipitation et de richesse du sol au Panama. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Biomasse aérienne, Plantation d'arbres, Gradient de précipitation, Tropiques, Transformation d'Aitchison.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisor: Carol MacKay. Vita. Includes bibliographical references. Available also from UMI Company.

The following dissertation outlines historical-archaeological research focused on the nineteenth-century, British plantation settlement at Lamanai, Belize. Archaeological data presented here include recent archaeological excavations (2014) and a study of previously excavated archaeological materials recovered at the site over the past 30 years (2009), conducted by this author. The study's archaeological data are synthesized in tandem with historical and documentary sources, comparative site data, and oral histories. Even though the study data span more than thirty years of recovery, it must be noted that very little research has focused on the late-colonial period at Lamanai to date. The most recent phase of archaeology is a foundational effort, which aims to set the stage for future late-colonial period, historical-archaeological studies. To this end, a great deal of effort has been spent here outlining the project's core theoretical and methodological foundations with which frame the current study and inform future research endeavors. Little is known about the eighteenth- and nineteenth- centuries at Lamanai, and to this end, the project aimed to answer questions regarding how life (residential, industrial, and administrative) was structured. While the archaeological and historical records have elucidated much about the plantation settlement at Lamanai to date, that data have also been frustratingly oblique and obfuscating with regard to intra-site variability among known British colonial activity and habitation areas.

Plantation eucalypts are a recent and rapidly growing industry in Australia, and will eventually replace the logging of old-growth forests. Over 40% of these plantations have been established in south-western Australia, where more than 160 000 ha of Eucalyptus globulus plantations now occur. In the early 1900’s, this species was widely planted as an exotic in South Africa, but succumbed to severe pest (Gonipterus sp.) and disease (Mycosphaerella sp.) problems. Similarly, in south-western Australia E. globulus is an exotic species, but with the additional threat that it is planted adjacent to indigenous eucalypts, which increases the possibility of pests and pathogens switching between closely related eucalypt hosts. Over the past ten years, there have been anecdotal reports of increasing levels of Mycosphaerella leaf disease (MLD) in E. globulus plantations in south-western Australia. This increase in disease level is of concern to the industry. To date there have been no comprehensive studies into the taxonomy, biogeography and population genetics of MLD in south-western Australia. This thesis investigated the impact of MLD in south-western Australia with a focus on its impact, taxonomy, biogeography and population genetics. It is the first study worldwide to quantify the relative impact of different Mycosphaerella species in a regional plantation estate. A survey of pest, disease and nutritional disorders (Chapter 2) found that MLD was the most severe and frequently occurring, single taxonomic health threat to 1 and 2-year-old E. globulus plantations in south-western Australia. For the first time, this survey identified and quantified the impact of pest and disease damage to E. globulus plantations in the region. There were differences in the disease levels between plantations and this was due to initial Mycosphaerella species composition and inoculum level, and local climatic conditions favourable for disease, rather than to the provenance planted or the nutritional status of the individual plantations. The survey for Mycosphaerella pathogens of eucalypts (Chapter 3) identified two new species of Mycosphaerella (M. ambiphylla and M. aurantia) and extended the known geographic range of eight other species (M. cryptica, M. gregaria, M. lateralis, M. marksii, M. mexicana , M. nubilosa, M. parva and M. suberosa). Of these: M. lateralis and M. mexicana were new records for Australia; and M. gregaria, M. nubilosa and M. parva were new records for Western Australia. A new anamorph, Phaeophloeospora ambiphylla was described and linked to M. ambiphylla. The occurrence of these new species and disease records in south-western Australia is significant for the plantation-eucalypt industry worldwide. The finding of two new species highlighted the need to quantify the disease impact of these on eucalypt plantations; and the extension of the range the remaining species raised important quarantine issues, concerned with the movement of plant material between regions and countries. The biogeographical investigation of Mycosphaerella (Chapter 4) identified that the most widespread and serious cause of MLD in south-western Australia is M. cryptica. In addition to occurring on the exotic E. globulus, it also occurs on two of the three important indigenous forestry eucalyptus species in this region. That is, on E. diversicolor, and E. marginata, but not on Corymbia calophylla. In terms of the plantation estate of E. globulus, however, M. nubilosa is the most widespread pathogen. The current study found that MLD on E. globulus is a complex of several different species, whereas, on E. diversicolor and E. marginata it is caused by only M. cryptica. Two species, M. cryptica and M. marksii were found commonly on adult E. globulus leaves. Although M. cryptica was the most frequent and serious cause of disease on adult leaves, M. marksii levels appear to be increasing and the future epidemiology of this pathogen should be closely monitored. There is some concern that these two MLD species could become an economically important problem on adult leaves of E. globulus. At present severe levels of MLD is significantly more common on juvenile than on adult foliage. The phylogenetic analysis (Chapter 5), based on ITS rDNA sequences from the present study and those obtained from GenBank accessions, found that Mycosphaerella is an assemblage of largely polyphyletic anamorph genera. Ten distinct clades emerged from the analysis. With the exception of the Dissoconium and the M. recutita clade, which comprised of two and one species respectively, none were comprised entirely of one anamorph genus alone. The anamorph genera represented were often dispersed across more than one clade, indicating that these anamorphs have arisen separately in different phylogenetic lineages. Cercospora, Stenella and Uwebraunia anamorphs each occurred in more than one separate clade. Although on the basis of rDNA sequence data Mycosphaerella appeared mostly monophyletic there was some evidence that the Mycosphaerella genus may be polyphyletic. This was particularly evident from the Dissoconium clade which grouped as closely to the outgroup Botryosphaeria taxon as it did with the remaining Mycosphaerella species. It was argued that a multi-gene phylogeny, which includes sequencing many species in other genera aligned with Mycosphaerella, is required in order to satisfactorily answer the question of whether Mycosphaerella is truly monophyletic. The phylogenetic analysis also showed that the taxonomy of Mycosphaerella based on ITS sequence data needs further clarification. Some species that are morphologically distinct, such as M. vespa and M. molleriana, shared identical ITS sequences. Other morphologically distinct species differed by as little as one or two nucleotides. Yet in other cases, the sequence variation amongst isolates from the same species differed substantially. Much of this variation in M. cryptica and other species was attributed to poorly edited sequences that had been lodged with GenBank. It was postulated that although a part of the remaining variation reflected the existence of cryptic species, some was likely to be genuine intra-species differences. It was concluded that further genes need to be sequenced, and more standardised cultural studies conducted in order to define species boundaries within Mycosphaerella. Based on the ITS rDNA sequence data, two different molecular methods for the identification of Mycosphaerella species from eucalypts were developed (Chapter 6). The first of these was a PCR-RFLP method that enabled the identification of Mycosphaerella species present on eucalypts in south-western Australia. A key is provided, which enabled the identification of species on a combination of PCR-RFLP DNA fragment migration patterns and a small number of morphological features. This key enables the identification of Mycosphaerella species more easily than keys that rely on morphological features alone. Therefore, this has made it easier for non-Mycosphaerella specialists to identify species from this genus. The second molecular method developed for the identification of Mycosphaerella species was that of primers that selectively amplify the DNA of M. cryptica and M. nubilosa, the two most important causes of MLD (Chapter 6). This will allow the rapid identification of these two species by non-specialists in Mycosphaerella taxonomy. The primers from the current study will also enable early diagnosis of the possible causal organism of MLD in a plantation. Once the use of these primers for amplifying DNA from leaf tissue has been optimised, they will also facilitate studies into the early infection process of M cryptica and M. nubilosa. For example, the presence of the pathogen may be detected prior to the appearance of symptoms. Studies may be conducted to determine the length of a hemi-biotrophic phase, and the extent of tissue colonisation both spatially and temporally, beyond the necrotic lesion in these two Mycosphaerella species. Previously, such studies have been hampered by the slow growth rate of these fungi in culture and the lack of media that would allow their selective isolation and detection by directly plating diseased and non-diseased host tissue. This study has clearly indicated that Mycosphaerella species are the major disease threat to E. globulus plantations in Western Australia. It has also shown that over the relatively short period of time of less than ten years the number of species recorded has increased from three to ten, and that disease severity has increased in plantations. It is therefore critical to continue the research on this genus in order to understand the biology, epidemiology and population genetics of this pathogen. This is necessary in order to inform tree selection and silvicultural practise that will minimise the future impact of MLD. This is particularly important if the industry moves towards clonal and hybrid forestry as has occurred elsewhere in the world. This study has laid the foundations for future research on this disease through the elucidation of the taxonomy of Mycosphaerella in south-western Australia and by providing some important molecular tools for its diagnosis and further study.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references (leaves 323-347). Also available in an electronic version.

Thesis (Ph. D.)--University of Pennsylvania, 1930. / Bibliography: p. iv-ix.

Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves i-ii).