The ability of eucalypt trees to grow in different soil aspects, under variable climatic and environmental conditions and to grow fast consistently producing straight stems has made them preferred plantation trees in many parts of the world. The world‘s increased demand for pulp wood has been the major contributor to the aggressive extensive development of eucalyptus plantations around the world. The productivity of these trees is however hindered in both native and introduced plantations by pests and pathogens. Chapter 1 of this thesis is a literature review on Teratosphaeria suttonii as the causative agent of Teratosphaeria Leaf Disease on Eucalyptus. The chapter highlights the taxonomic placement of T. suttonii in the genus Teratosphaeria and the name changes of the species as a consequence of molecular taxonomy. The effects of the pathogen on Eucalyptus plantations in different parts of the world as well as the incidence and range of Eucalyptus species that host the pathogen are presented. In addition the review summarizes much of the information published on the distribution, hosts range and evolutionary relationships of T. suttonii with closely related species in the genus Teratosphaeria. In conclusion, it highlights the lack of understanding of the degree of diversity of the pathogen from different parts of the world. In order to characterize and establish the phylogenetic relationships between T. suttonii isolates from different countries, chapter 2 of this thesis considered microscopic examination and DNA sequence comparisons of isolates from its native and introduced localities. The isolates were classified into a single genetically and morphologically diverse group within which representatives of different countries were intermixed in smaller groups. A high level of genetic variation was evident among Australia isolates but despite the diversity there was no overwhelming evidence for sibling species. In Chapter 3 of this thesis eleven microsatellite markers were developed from three T. suttonii isolates obtained from 2 geographic areas. The markers were used in Chapters 4 and 5 to investigate the genetic diversity of T. suttonii in both its native and introduced environments and to establish factors underlying such diversity. The application of the markers in Chapters 4 and 5 provide the first consideration of the diversity of T. suttonii in both its native and introduced localities respectively. Both native and introduced pathogen populations exhibit substantially high genotypic diversities. It is evident from these studies that Australia is the point of origin of T. suttonii and that anthropogenic activities have resulted in repeated introductions of the pathogen from Australia into many countries. Teratosphaeria suttonii is of great significance to the eucalyptus plantation industry across the world. Movement of diseased germplasm and introduction of new genotypes favors pathogen adaptability. In order to reduce the distribution of the pathogen into new areas or any other places where it might have negative effects, strict quarantine procedures should be followed. / Thesis (PhD)--University of Pretoria, 2013. / gm2013 / Microbiology and Plant Pathology / Unrestricted

O plantio de árvores para finalidades industriais é um tipo de uso do solo que gera controvérsias em vários países. Ao transformarem paisagens, afetam comunidades rurais alterando suas realidades material e simbólica. A redução da vazão dos corpos d\"água é um dos mais recorrentes pontos de discussão. No Brasil, o eucalipto é a espécie arbórea mais utilizada para fins industriais. Impulsionados pela produção de celulose, esses plantios estão presentes na região Vale do Paraíba Paulista. Esta pesquisa procurou identificar e analisar como as representações do efeito dos plantios de eucalipto nas vazões de cursos d\"água são construídas nos territórios rurais dos municípios de Caçapava, Santa Branca e Cunha. Entende-se que compreender essas visões é uma forma de reconhecer os conhecimentos de indivíduos que possuem experiências fundamentadas nesses territórios, interagindo com essa atividade econômica e lidando com as consequências advindas da mesma. Para tanto, realizamos uma série de noventa entrevistas semiestruturadas dialogando com as teorias das representações sociais e do construcionismo ambiental. Como resultado, compreendemos que as representações sociais que fundamentam este problema ambiental não são fixas, se transformam em conjunto com a sociedade e em diálogo com as modificações econômicas e técnicas que caracterizam o setor, bem como com as alterações dos contextos históricos, sociológicos, ambientais e culturais que distinguem a região. / Tree plantation for industrial purposes is a controversial land use in several countries. By transforming landscapes, they affect rural communities, changing their material and symbolic realities. Reduced waterflow is one of the most contentious issues. In Brazil, eucalyptus is the most commonly used tree species for industrial purposes. Driven by pulp production, these plantations are found in the Paraíba Valley region, São Paulo. The aim of this study was to identify and analyze how the representations of eucalyptus plantations effect on waterflows are constructed in the rural territories of Caçapava, Santa Branca and Cunha municipalities. It is recognized that understanding these visions is a way of acknowledging individuals who have grounded experiences in these territories, interacting with this economic activity and dealing with the consequences that arise from it. To do so, we carried out a series of ninety semi-structured interviews based on the theories of social representations and environmental constructionism. As a result, we understand that the social representations that underpin this environmental problem are not fixed. They change along with society and are linked to the economic and technical changes that characterize the sector, as well as the changes of historical, sociological, environmental and cultural contexts that distinguish the region.

There is a range of detailed research on edge effects using field data at local scales. However, the scientific literature lacks studies that aim to understand its characteristics in forest fragments using larger scales. Also, few works have considered the influences that each fragment of the landscape imposes on its neighbour. Since biological processes linked to fragmentation and degradation commonly start at edges and influence the dynamics of forest communities, studies on edge effects are crucial for the development of management and conservation plans. Lidar technologies have been used in several studies on forest structure, but few have investigated edge effects. This dissertation presents two distinct applications of lidar for studying anthropogenic-caused edges in different scenarios and ecosystems. In the first study, edge effects in commercial Eucalyptus plantations and fragments of the Atlantic Forest, located in the State of São Paulo, were evaluated by quantifying the differences in height and understory density in the edge vegetation vs core. We also sought to understand the influences that each type of adjacent fragment (Eucalyptus, native forest or pasture) imposes on the neighbouring vegetation. Edge effects, regarding height and understory density, on fragments of native vegetation adjacent to Eucalyptus plantations and vice-versa were more attenuated than nearby pastures. The results indicated that the protection of native forests in silviculture areas besides favouring the maintenance of local ecosystem services (provision and maintenance of water flow, diversity of flora and fauna species, natural pest control, etc.) could help maintain the homogeneity of the stands due to their ability to minimise edge effects. This protection could favour the occurrence of border Eucalyptus more similar to the ones in the core. In the second study, edge effects caused by seismic lines, i.e. corridors cut through the forest during the process of exploration of gas and oil, in areas of Boreal Forest in the central region of Alberta is addressed. Besides quantifying the effects of distance from seismic lines over height and fractional cover on the neighbouring vegetation, the interactions between these variables and primary vegetation growth factors related to the topographic position, incident radiation and surface geology were evaluated. The results showed that significant changes in vegetation structure adjacent to forest edge occur close to seismic lines, including reduced tree height and cover. Random Forest analyses revealed that the distance from the seismic line, incident radiation and surface water accumulation potential (inferred from the topographic position index) are the most critical variables for height and fractional cover prediction. Overall, lidar proved to be a robust tool for assessing the spatial and ecological dimensions of edge effects in different scenarios. With this in mind, management and conservation strategies for fragmented areas could benefit from this technology to reduce the impact from edge effects on ecosystems. / Há uma gama de pesquisas detalhadas sobre efeitos de borda usando dados de campo em escalas locais. No entanto, a literatura científica carece de trabalhos que visem compreender suas características em fragmentos florestais utilizando escalas maiores. Além disso, poucos estudos levaram em conta as influências que cada fragmento da paisagem impõe sobre seu vizinho. Uma vez que processos biológicos ligados à fragmentação e degradação geralmente se iniciam pelas bordas e influenciam a dinâmica das comunidades florestais, estudos sobre efeitos de borda são cruciais para o desenvolvimento de planos de manejo e conservação. Tecnologias lidar têm sido usadas em diversos estudos sobre a estrutura de florestas, mas poucos trabalhos investigaram efeitos de borda. Esta dissertação apresenta duas aplicações distintas do lidar para o estudo de bordas criadas pelo homem em diferentes cenários e ecossistemas. No primeiro estudo, efeitos de borda em plantios comerciais de eucalipto e fragmentos de Mata Atlântica, no Estado de São Paulo, foram avaliados por meio da quantificação das diferenças na altura e densidade do sub-bosque na vegetação da borda vs. interior. Buscou-se também compreender as influências que cada tipo de fragmento adjacente (eucalipto, floresta nativa ou pasto) impõe sobre a vegetação vizinha. Os efeitos de borda, em termos de altura e densidade do sub-bosque, em fragmentos de vegetação nativa adjacentes aos plantios de eucalipto e vice-versa foram mais atenuados do que próximo às pastagens. Os resultados indicaram que a proteção de florestas nativas em áreas de silvicultura além de favorecer a manutenção de serviços ecossistêmicos locais (provisão e manutenção do fluxo de água, diversidade de espécies da flora e fauna, controle natural de pragas etc.) poderia ajudar a manter a homogeneidade dos talhões devido à sua capacidade de minimizar os efeitos de borda. Esta proteção poderia favorecer a ocorrência de eucaliptos de borda mais semelhantes aos de interior. No segundo estudo, foram abordados efeitos de borda causados pela abertura de linhas sísmicas durante o processo de exploração de gás e petróleo em áreas de Floresta Boreal, na região central de Alberta. Além da quantificação dos efeitos da distância das linhas sísmicas na altura e cobertura arbórea da vegetação vizinha, foram avaliadas as interações entre tais variáveis e fatores de crescimento primário da vegetação relacionados a posição topográfica, radiação e superfície geológica. Os resultados mostraram que variações significativas na estrutura da vegetação adjacente à borda da floresta ocorrem próximas às linhas sísmicas, incluindo altura e cobertura arbórea reduzidas. Análises por meio de florestas aleatórias (random forest) revelaram que a distância da linha sísmica, a radiação incidente e o potencial de acumulação de água superficial (inferida a partir do índice de posição topográfica) são as variáveis mais importantes para predição de altura e cobertura arbórea. No geral, o lidar se mostrou uma ferramenta robusta para avaliar as dimensões espaciais e ecológicas dos efeitos de borda em diferentes cenários. Com isso em mente, estratégias de manejo e conservação para áreas fragmentadas poderiam se beneficiar desta tecnologia para redução do impacto de efeitos de borda nos ecossistemas.

Les plantations d'Eucalyptus, au Congo (région de Pointe-Noire) comme au Maroc (forêt de la Maâmora), soulèvent des controverses quant à leurs effets sur des sols sableux pauvres en matière organique. Dans un enjeu de développement durable de tels écosystèmes anthropiques, les recherches sur le sujet se sont multipliées. Toutefois, les connaissances relatives au fonctionnement biologique des sols sous ces plantations méritent encore d'être approfondies. Principaux acteurs de ce fonctionnement biologique, les organismes vivant dans ces sols et leurs activités ne sont que trop peu décrites, et nécessitent en ce sens de se trouver au cœur des études sur le sujet. Notre travail de thèse s'inscrit dans ces problématiques. Ainsi, nous évaluons les conséquences du reboisement sur les communautés de la macrofaune et des microorganismes de ces sols, et également l'activité des enzymes clés liées aux principaux cycles biogéochimiques (C, N et P).Cette recherche présente la particularité de la prise en compte simultanée de deux facteurs peu souvent évoqués, que sont, l'« âge des plantations » et la « profondeur du sol ». Nous avons abordé ces questions par une étude multi-échelle.Ainsi, nous avons étudié les macroinvertébrés quant à leur diversité taxonomique et à leur composition verticale, selon une approche combinée (TSPF + carré anglais). Par la suite, les premières caractérisations de structure et de diversité des communautés microbiennes ont été réalisées. Ceci, par mesure de densité et par déterminations morphotypiques (cultures in vitro) et génétiques (DGGE), au niveau des communautés totales. Par mesure du potentiel métabolique pour ce qui est des communautés fonctionnelles (plaques Biolog). Enfin, l'activité biologique des sols a été évaluée en mesurant l'activité de huit enzymes et l'activité microbienne globale (hydrolyse FDA).Ainsi, par comparaison à la forêt naturelle adjacente, cette étude nous a permis de mettre en évidence que l'introduction d'eucalyptus sur savane (Congo) ou sur chêne-liège dégradé (Maroc), modifie la structure et la diversité des communautés de la macrofaune et des microorganismes du sol ainsi que le profil des activités enzymatiques. Aussi bien en fonction de l'âge des plantations que de la profondeur du sol, ceci est valable. C'est le fonctionnement biologique qui se trouve donc impacté.Les proportions et les conséquences de cet impact restent toutefois particulières à chaque cas. Il faut cependant noter exception pour les activités enzymatiques liées au cycle de l'azote, qui apparaissent influencées de façon comparable dans les deux cas à l'étude. Ces activités diminuent significativement avec l'âge du peuplement, confirmant le statut déficitaire en azote de ce type de plantation. / Eucalyptus plantations in Congo (Pointe-Noire region) and in Morocco (Mamora forest) raised certain controversies regarding their effects on the sandy poor soils. In such anthropogenic ecosystems, researches on the subject have multiplied in order to ensure their sustainable management. However, knowledge on the biological functioning of soils in these plantations still needs to be explored. Main actors of this biological functioning are soil organisms and their activities which have been described very little, and need to be more studied. Our thesis encompasses this problematic. Therefore, we evaluated the impact of reforestation on the communities of macrofauna and microorganisms of soil, and the activity of different key enzymes, as well, related to main biogeochemical cycles (C, N and P). This research presents, particularly, a simultaneous consideration of two factors rarely mentioned before: the "age of the plantations" and "soil depth". We addressed these issues by a multi-scale study. We studied macroinvertebrates by their taxonomic diversity and vertically composition by a combined approach (TSPF + English square). Subsequently, the characterization of structure and diversity of microbial communities was done by density measurements, morphotype-specific (in-vitro culture) and the genetic determinations (DGGE) and by measuring the metabolic potential in terms of functional communities (Biolog plates). Finally, soil biological activity was evaluated by determining the activity of eight different enzymes and the total microbial activity (FDA hydrolysis).Therefore, as compared to the adjacent natural forest soils, this study allowed us to demonstrate that the introduction of eucalyptus plantations, in savanna (Congo) or in degraded cork oak ecosystem (Morocco), alters the structure and diversity of macrofauna communities, soil microorganisms and the enzymatic activity profiles. Consequently, the biological functioning of the soils is impacted both in terms of the age of plantations and soil depth. However, the proportions and the consequences of this impact were very specific in each case, with the exception of enzymatic activities related to the nitrogen cycle, which influenced comparatively in both studies. These activities decreased significantly along with the stand age of eucalyptus plantations, confirming the deficient status of nitrogen in such plantations.

Made available in DSpace on 2015-03-05T16:19:36Z (GMT). No. of bitstreams: 0 Previous issue date: 26 / Nenhuma / Este estudo foi realizado em dez fragmentos de floresta ripária localizados no sul do Brasil (30°09’S, 51°36’W; 46 m de altitude). Entre as dez florestas ripárias selecionadas, cinco estavam circundadas por pastejo de gado e as outras cinco estavam circundadas por plantações de eucalipto. Foi avaliada a sustentabilidade de Campomanesia rhombea, Diospyros inconstans, Myrciaria cuspidata e Sebastiania commersoniana através de análises da estrutura de tamanho, as quais foram realizadas em duas escalas. Em escala local, foram consideradas as populações presentes nos fragmentos circundados por pastejo de gado ou por plantações de eucalipto e, em escala regional considerou-se também áreas florestais maiores, tomadas como referência (Inventário Florestal Contínuo do Rio Grande do Sul). Em escala local, nas populações presentes em fragmentos circundados por plantações de eucalipto, prevaleceram indivíduos de pequenas classes de tamanho, e em áreas expostas ao pastejo de gado, as mesmas espécies apresentaram uma falha / This studied was carried in ten riparian forest fragments located southern Brazil. Of the ten riparian forests selected for study, five were embedded in pasturelands and five in eucalyptus plantations. We assessed the population sustentability of Campomanesia rhombea, Diospyros incontans, Myrciaria cuspidata and Sebastiania commersoniana through analyses of size structure, which were carried out at two scales. At a local scale, we consider populations in fragments surrounded by pastures or eucalyptus forest plantations, and at a regional scale we also consider larger forest tracts taken as reference areas (Rio Grande do Sul Forest Inventory databank). At local scale, the populations in fragments embedded by eucalyptus plantations prevailed small size classes individuals, and in areas exposed to cattle ranching, the same species seem to have a recurring failure of small individuals. Regional analyses included only established individuals with DBH > 1.6 cm. In this scale, populations in fragments surrounded by

The main objective of this study was to make an inventory of abandoned eucalyptus plantations due to remaining tree stumps in the Brazilian Pampa biome, focusing on the two counties Pedras Altas and Candiota. In the study, the term “ghost fields” was used for abandoned eucalyptus plantations – land areas that were previously planted with eucalyptus and subsequently left unproductive for a number of years, no longer used for eucalyptus and not converted into e.g. pasture or soybean plantation. After three successive rotations, typically every 21 years, eucalyptus land needs to be processed mechanically to remove remaining stumps and allow new plantation, but stump clearing is costly, and in some cases, non-industrial owners leave the fields ghosted. More than half of the native vegetation, primarily grassland, in the Pampa has been converted into agriculture and forestry, and eucalyptus species are especially popular for plantation because of speedy growth and adaptability to harsh conditions. The loss of native grasslands to continuous short-rotation eucalyptus plantation for commercial use has resulted in soil degradation and biodiversity loss. The demand for productive land, and importance of conserving native vegetation, made it relevant to investigate the extent of ghost fields and the correlation between suppressed native vegetation and ghost fields and between suppressed native vegetation and eucalyptus plantation in general. The study showed that 11 percent (2,727 out of 24,746 hectares) of eucalyptus plantation in the focus area, comprising Pedras Altas and Candiota County, was ghosted for a period of 1-11 years between 2012-2023. Based on extrapolation of the findings in the focus area, 26,323 hectares (11 percent) out of the total 239,297 hectares of eucalyptus plantation in the Pampa may have been ghosted for a number of years between 2012-2023 because of remaining tree stumps. 500 (out of 980) hectares of ghost fields in Pedras Altas County and 543 (out of 1747) hectares of ghost fields in Candiota County were connected to areas with recent suppression of native vegetation (2004-2022). 8,240 (out of 13,200) hectares of eucalyptus plantation, including ghost fields, in Pedras Altas County and 4,829 (out of 11,546) hectares of eucalyptus plantation, including ghost fields, in Candiota County were connected to areas with recent suppression of native vegetation.

Submitted by William Justo Figueiro (williamjf) on 2015-08-28T17:15:44Z No. of bitstreams: 1 32e.pdf: 2782096 bytes, checksum: 5928fd17fc9df8b5902bae55c6c45acf (MD5) / Made available in DSpace on 2015-08-28T17:15:44Z (GMT). No. of bitstreams: 1 32e.pdf: 2782096 bytes, checksum: 5928fd17fc9df8b5902bae55c6c45acf (MD5) Previous issue date: 2013-08-27 / CMPC - Celulose Riograndense / A vegetação do sul do Brasil é composta pelos biomas Pampa e Mata Atlântica. Nossas áreas de estudo situam-se próximo aos limites destes dois biomas, formando um mosaico campo-floresta. A pecuária e a silvicultura de eucalipto são atividades largamente difundidas ao longo destas formações. A mudança de manejo da matriz, da pecuária para a silvicultura de eucalipto, pode levar a alterações nas características autoecológicas de espécies arbóreas florestais. O estudo das características autoecológicas em ambientes com diferentes históricos de uso da terra pode ajudar a compreender como as espécies arbóreas respondem às alterações de habitat ou das condições ambientais. Este estudo objetiva analisar como atributos autoecológicos entre espécies arbóreas florestais variam segundo uma mudança de manejo da matriz no extremo sul da Mata Atlântica, de campos nativos com pecuária extensiva para plantações de eucaliptos sobre essas pastagens. De forma específica, pretende-se (i) determinar o efeito da mudança de manejo sobre atributos autoecológicos entre espécies, e havendo este efeito, (ii) que padrões de alteração autoecológica podem ser identificados entre espécies. De acordo com nossos resultados, a mudança de manejo da matriz da paisagem causou alterações nos padrões autoecológicos das espécies arbóreas. A amplitude destas variações foi diferente para cada espécie e dependeu de sua plasticidade fenotípica e das condições ambientais locais. A longo prazo, os padrões de alterações autoecológicas encontrados podem refletir uma mudança na composição de espécies em decorrência da mudança de manejo. / The vegetation of southern Brazil is composed of Pampa and Atlantic Rain Forest biomes. Our study areas are located near the boundaries of these two biomes, forming a 24 grassland-forest mosaic. The livestock and eucalyptus plantations are widely diffused throughout these formations. The change of matrix management, of livestock for eucalyptus plantations, can lead to changes in the autoecological attributes of forest tree species. The study of the autoecological attributes in environments with different historical of land use can help to understand how tree species respond to changes in habitat or environmental conditions. This study aims to analyze how autoecological attributes between forest tree species varies as a consequence of change in management matrix at the southern Atlantic Rain Forest, of grasslands with extensive livestock for eucalyptus plantations on these pastures. Specifically, we intend to (i) determine the effect of changing management on autoecological attributes among species, and having this effect, (ii) what patterns of autoecological change can be identified between species. According to our results, the change in management of landscape matrix caused changes in autoecological patterns of tree species. The extent of these variations was different for each species and depended on their phenotypic plasticity and local environmental conditions. Long-term, patterns of autoecological change found may reflect a change in species composition due to the change in management of landscape matrix.