Resumo: Este trabalho teve como objetivo investigar a possibilidade de plantas utilizadas como cercas-vivas e quebra-ventos, bem como plantas invasoras comuns em pomares cítricos, hospedarem o Citrus leprosis virus, cytoplasmic type (CiLV-C) e servirem de inóculo para os citros. Em casa-de-vegetação, ácaros provenientes de uma criação-estoque sobre frutos de laranja Pêra, com sintomas de leprose, foram transferidos para folhas isoladas por barreira adesiva de: hibisco (Hibiscus rosa-sinensis L.), malvavisco (Malvaviscus arboreus Cav.), grevílea (Grevilea robusta A. Cunn.), urucum (Bixa orellana L.), trapoeraba (Commelina benghalensis L.) e laranja [Citrus sinensis (L.) (Osbeck)]. Após 90 dias da infestação, os ácaros descendentes foram transferidos para mudas de laranja "Natal". Amostras de tecidos das plantas testes se mostraram positivos para todas as plantas inoculadas com ácaros virulíferos por análise de RT-PCR utilizando-se de "primers" específicos para detecção do CiLV-C e foram verificadas a presença de partículas virais em hibisco, laranja, malvavisco, e trapoeraba em análise de Microscopia Eletrônica de Transmissão (MET). Em campo, laranja, malvavisco, grevílea e sansão-do-campo foram plantados próximos a plantas-teste de laranja e infestados com ácaros virulíferos. Essas espécies foram avaliadas quanto à presença de ácaros, à incidência e à severidade da doença. Foi possível observar que a incidência e a severidade da leprose foram maiores nas plantas de laranja que estavam próximas às laranjeiras infestadas, seguidas daquelas próximas a malvavisco e sansão-do-campo, que diferiram estatisticamente de grevílea. Estes resultados indicam que as plantas analisadas podem ser importantes na epidemiologia da doença. / Abstract: The objective of this work was to investigate the possibility that hedgerows, windbreaks, and weeds normally found in citrus orchards could host Citrus leprosis virus, cytoplasmic type (CiLV-C), serving as its source of inoculum. In greenhouse, mites reared onto sweet orange fruits var. "Pêra" symptomatic for leprosis were transferred to leaves, isolated by adhesive barrier, of Hibiscus rosasinensis, Malvaviscus arboreus, Grevilea robusta, Bixa orellana, Commelina benghalensis and Citrus sinensis. After 90 days of infestation, the descendant mites were transferred to Natal sweet orange plants to verify the transferability of the virus back to citrus. Non-viruliferous mites, which had no feed access to diseased tissue, were used as control. Localized lesions (chlorotic or necrotic spots, ringspots) developed in almost all tested plants. Tissue samples of plants infested with viruliferous and non-viruliferous mites were submitted to RT-PCR with specific primers to CiLV-C. Transmission electron microscopy analyses detected the presence of viral inclusions in C. benghalensis H. rosa-sinensis, M. arboreus, and C. sinensis. In experimental groves, C. sinensis, G. robusta, M. arboreus and Mimosa caesalpinaefolia were planted and infested with viruliferous mites around citrus plants. There was a clear variation in leprosis incidence and severity observed in sweet orange plants depending on the alternative host cultivated beside them. The higher intensity of the disease was observed in sweet orange plants that were close to C. sinensis, followed by those close to M. arboreus and Mimosa caesalpinaefolia. The intensity of leprosis in sweet oranges planted near G. robusta was significantly lower than in those cultivated close to the other hosts. These results suggest that the alternative hosts tested can play a role in the epidemiology of the disease, serving as sources of inoculum of the virus. / Orientador: Carlos Amadeu Leite de Oliveira / Coorientadora: Juliana de Freitas Astúa / Banca: Marinês Bastianel / Banca: André Luis Matioli / Banca: Nilza Maria Martinelli / Banca: Sérgio Antonio de Bortoli / Doutor

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Master of Arts / Department of Geography / J. M. Shawn Hutchinson / Windbreaks are a valuable resource in conserving soils and providing crop protection in western Kansas and other Great Plains states. Currently, Kansas has neither an up-to-date inventory of windbreak locations nor an assessment of their condition. The objective of this study is to develop remote sensing and geographic information system methods that rapidly identify and assess the condition of windbreaks in Ford County, Kansas. Ford County serves as a pilot study area for method development with the intent of transferring those methods to other counties/regions in Kansas and the Great Plains. A remote sensing technique known as object-based classification was used to classify windbreaks using color aerial photography acquired through the 2008 National Agricultural Imagery Program. Object-based classification works by segmenting imagery where areas with similar spectral, shape, and textural properties are grouped into vectors (i.e., objects) that are later used as the basis for image classification. Using this technique, 355 windbreaks, totaling nearly 1,012 acres (410 hectares), were identified in Ford County. When compared to a spatial data set of confirmed windbreak locations generated via a heads-up digitizing process, the location of windbreaks identified using object-based classification results agreed approximately 81% of the time. Mean textural and spectral values were then combined and used to place identified windbreaks into three condition categories (good, fair, and poor) using a manual classification approach. Analysis showed the area of windbreaks in good condition to be 170 hectares, with the remaining 171 hectares of windbreaks falling in the fair or poor classes. Methods detailed in this study proved successful at rapidly identifying windbreak location and for providing useful condition class results for windbreak renovation and restoration planning.

La façade littorale du Grand Port Maritime de Dunkerque est une cellule sédimentaire quasi-fermée où les formes dunaires résultent de l’imbrication de facteurs humains et naturels. Ce littoral peut être divisé en deux parties : la partie Ouest est constituée d’un cordon bordier sur une longueur de 7 km (plage du Clipon) et le long de la partie Est, la plage est adossée à une digue en enrobé bitumineux de 6 km de long (digue du Braek) où des transferts sableux se produisent. L’objectif de cette étude est de (1) caractériser les formes dunaires et leur évolution sur un site artificiel, (2) quantifier le transport éolien sur le haut de plage, le versant externe de la dune bordière et la digue du Braek, et (3) proposer des mesures de gestion afin de remédier aux contraintes d’exploitation engendrées par les dépôts éoliens sur les infrastructures. A moyen terme (28 ans), l’analyse diachronique de photographies aériennes montre que les superficies dunaires ont fortement augmenté depuis 1983. A court terme (2 ans), des mesures topographiques révèlent que les dunes continuent de se développer aujourd’hui mais gardent la marque des interventions anthropiques passées. Sur la digue du Braek, des formes dunaires se sont naturellement constituées sur l’asphalte. Le sable a été colonisé par Ammophila arenaria qui s’est enraciné sous l’enrobé par l’intermédiaire de fissures. Une typologie de ces dunes de digue a été proposée. A l’Est, des dunes se développent en pied de digue en raison de l’interruption des transferts sédimentaires longitudinaux par une jetée. Des piégeages éoliens in situ ont montré que le transport éolien était essentiellement contrôlé par la vitesse du vent et la source de sable disponible. Par vents frontaux et obliques, les dunes de pied de digue constituent la principale source des envols, et le transport éolien est favorisé par une accélération du vent sur le versant exposé. Différents types de brise-vent ont été testés sur l’ensemble du site afin de trouver le meilleur mode de gestion souple de ces envols de sable. Ces analyses montrent que si la localisation des structures brise-vent a une grande influence sur leur efficacité, les systèmes habituellement utilisés sur les plages (ganivelles, filets synthétiques) peuvent aussi favoriser le développement de dunes sur une digue en asphalte. Les mesures de gestion envisagées sont la stabilisation des principales sources de sable en pied de digue ainsi que le renforcement de la dune bordière aux endroits les plus fragiles. / The coastline of Dunkirk seaport is a sedimentary cell where dune morphology is the result of both natural processes and human intervention. This shoreline can be divided in two parts: a western part of 7 km long, where a macrotidal beach is backed by naturally developing coastal dunes, and an eastern part consisting of a 6 km long asphalt dike overtopped in places by low elevated aeolian dunes. This study aims at (1) describing aeolian dunes and their evolution on a human-altered coast, (2) quantifying aeolian sand transport on the upper beach, the seaward slope of the foredune and the asphalt dike, and (3) suggesting management measures in order to solve windblown sand accumulation problems on harbour infrastructures. On the middle term (28 years), diachronic analysis of aerial photographs shows rapid development of dunes area since 1983. On the short term (2 years), topographic surveys reveal that dune development is still ongoing, although dune morphology keeps the marks of passed human interventions. Dunes have naturally developed on asphalt and their formation is initiated by Ammophila arenaria colonisation of numerous perpendicular cracks in the dike. A typology of these dunes is proposed. Dike toe dunes have developed at the beach/dike contact in the most eastern part of the site, where a jetty is interrupting net sediment transport. In situ field measurements revealed that aeolian sand transport is mainly controlled by wind speed and the source of sand available. Under oblique to direct onshore winds, dike toe dunes are the main source of windblown sand on the dike, and aeolian transport is enhanced by a wind speedup on the windward slope. Different kinds of windbreaks have been tested in order to solve uncontrolled aeolian sand transport problems on the dike, as well as to consolidate foredunes. It appeared from the topographic surveys carried out on the windbreaks that although their location seemed to play a major role on the amount of sand captured, fences and synthetic fabrics deployed on sandy surfaces were also able to trap windblown sand on a seaport dike. Management measures considered are a stabilisation of main sand sources at the dike toe and consolidation of foredunes with windbreaks.

Entender o clima dos espaços urbanos em suas diversas conformações é objeto de grande interesse para a melhoria da qualidade de vida da população que usufrui desses espaços. Cada microclima requer intervenções específicas para a obtenção de condições favoráveis de conforto higrotérmico tendo em vista a saúde e o bem estar de seus usuários. O objetivo desta pesquisa foi avaliar elementos de vegetação como barreira aos ventos visando o conforto térmico em espaços abertos. O procedimento utilizado foi quantificar a interferência de elementos vegetais na passagem dos ventos, na altura dos pedestres, a partir de configurações de vegetação pré-estabelecidas. O cenário eleito para este estudo foi a área externa do Campus da Universidade Metodista de Piracicaba (UNIMEP), localizado no bairro Taquaral em Piracicaba, SP. Embora trate-se de clima predominantemente quente, há relatos de desconforto no local em dias frios decorrente do excesso de ventos. Foram estudadas três diferentes espécies dispostas em arranjos com intenção de barreira aos ventos: Jasminum mesnyi Hance, Pseudosasa japonica (Steud.) Makino e Pinus caribaea Morelet. As variáveis microclimáticas medidas foram temperatura do ar, umidade relativa do ar e velocidade dos ventos, em três posições distintas por espécie: em um campo aberto próximo, antes e depois da barreira. O período de coleta de dados foi das 9 às 21 horas, em intervalos de 3 minutos, durante três dias por espécie, nos meses de agosto e setembro de 2014. Os resultados obtidos no campo aberto foram comparados aos registrados na estação meteorológica da ESALQ-USP no mesmo período. Foi feita a medição do LAI (Índice de Área Foliar) das espécies. Foram realizadas simulações computacionais em modelagem da área no programa ENVI-met® 3.1, com os dados de Densidade de Área Foliar (LAD) estimados a partir dos valores de LAI obtidos nas medições, como parte dos estudos de viabilidade para adoção do LAI como parâmetro na previsão de resultados, o que permitiria sua aplicabilidade a outras espécies. Os resultados obtidos indicam uma tendência favorável a este princípio, porém estudos com maior intensidade amostral são necessários para obtenção desta correlação. Outras aplicações podem ser beneficiadas com esta linha de estudo, como a previsão do risco de queda de árvores. / Understanding the climate of urban spaces in their various conformations is subject of great interest to improve the quality of life of the population that occupies these spaces. Each microclimate requires specific interventions to obtain favorable terms of hygrothermal comfort owing to health and welfare of its members. The objective of this research was to evaluate plant matter as a barrier to winds targeting the thermal comfort in open spaces. The procedure was quantifying the interference of tree elements in the passage of winds, at a pedestrian level, from pre-established vegetation settings. The chosen scenario for this study was the campus of the Universidade Metodista de Piracicaba (UNIMEP), located in the Taquaral neighborhood in Piracicaba, SP. While dealing is predominantly warm weather, discomfort is reported in cold weather due to the excessive winds in the external areas. We studied three different species placed in arrangements intended as wind barriers: Jasminum mesnyi Hance, Pseudosasa japonica (Steud.) Makino and Pinus caribaea Morelet. Microclimate variables measured were air temperature, relative humidity and wind speed, in three different positions by species: in a nearby open field, before and after the barrier. The data collection period was from 9 to 21 o\'clock, at 3-minute intervals for three days by species, in August and September 2014. Results obtained in open field were compared with those recorded at ESALQ-USP\'s weather station during the same period. The LAI (Leaf Area Index) of the species was measured. Computer simulations were performed by modeling the area in ENVImet® 3.1 program, with the Leaf Area Density data (LAD) estimated from the LAI values obtained in measurements, as part of feasibility studies for the adoption of LAI as a parameter in the forecast results, allowing its applicability to other species. The results indicate a positive trend towards this principle, however, studies with larger sample intensity are required in order to achieve this correlation. Other applications may benefit from this line of study, such as the prediction of falling trees risks.

Entender o clima dos espaços urbanos em suas diversas conformações é objeto de grande interesse para a melhoria da qualidade de vida da população que usufrui desses espaços. Cada microclima requer intervenções específicas para a obtenção de condições favoráveis de conforto higrotérmico tendo em vista a saúde e o bem estar de seus usuários. O objetivo desta pesquisa foi avaliar elementos de vegetação como barreira aos ventos visando o conforto térmico em espaços abertos. O procedimento utilizado foi quantificar a interferência de elementos vegetais na passagem dos ventos, na altura dos pedestres, a partir de configurações de vegetação pré-estabelecidas. O cenário eleito para este estudo foi a área externa do Campus da Universidade Metodista de Piracicaba (UNIMEP), localizado no bairro Taquaral em Piracicaba, SP. Embora trate-se de clima predominantemente quente, há relatos de desconforto no local em dias frios decorrente do excesso de ventos. Foram estudadas três diferentes espécies dispostas em arranjos com intenção de barreira aos ventos: Jasminum mesnyi Hance, Pseudosasa japonica (Steud.) Makino e Pinus caribaea Morelet. As variáveis microclimáticas medidas foram temperatura do ar, umidade relativa do ar e velocidade dos ventos, em três posições distintas por espécie: em um campo aberto próximo, antes e depois da barreira. O período de coleta de dados foi das 9 às 21 horas, em intervalos de 3 minutos, durante três dias por espécie, nos meses de agosto e setembro de 2014. Os resultados obtidos no campo aberto foram comparados aos registrados na estação meteorológica da ESALQ-USP no mesmo período. Foi feita a medição do LAI (Índice de Área Foliar) das espécies. Foram realizadas simulações computacionais em modelagem da área no programa ENVI-met® 3.1, com os dados de Densidade de Área Foliar (LAD) estimados a partir dos valores de LAI obtidos nas medições, como parte dos estudos de viabilidade para adoção do LAI como parâmetro na previsão de resultados, o que permitiria sua aplicabilidade a outras espécies. Os resultados obtidos indicam uma tendência favorável a este princípio, porém estudos com maior intensidade amostral são necessários para obtenção desta correlação. Outras aplicações podem ser beneficiadas com esta linha de estudo, como a previsão do risco de queda de árvores. / Understanding the climate of urban spaces in their various conformations is subject of great interest to improve the quality of life of the population that occupies these spaces. Each microclimate requires specific interventions to obtain favorable terms of hygrothermal comfort owing to health and welfare of its members. The objective of this research was to evaluate plant matter as a barrier to winds targeting the thermal comfort in open spaces. The procedure was quantifying the interference of tree elements in the passage of winds, at a pedestrian level, from pre-established vegetation settings. The chosen scenario for this study was the campus of the Universidade Metodista de Piracicaba (UNIMEP), located in the Taquaral neighborhood in Piracicaba, SP. While dealing is predominantly warm weather, discomfort is reported in cold weather due to the excessive winds in the external areas. We studied three different species placed in arrangements intended as wind barriers: Jasminum mesnyi Hance, Pseudosasa japonica (Steud.) Makino and Pinus caribaea Morelet. Microclimate variables measured were air temperature, relative humidity and wind speed, in three different positions by species: in a nearby open field, before and after the barrier. The data collection period was from 9 to 21 o\'clock, at 3-minute intervals for three days by species, in August and September 2014. Results obtained in open field were compared with those recorded at ESALQ-USP\'s weather station during the same period. The LAI (Leaf Area Index) of the species was measured. Computer simulations were performed by modeling the area in ENVImet® 3.1 program, with the Leaf Area Density data (LAD) estimated from the LAI values obtained in measurements, as part of feasibility studies for the adoption of LAI as a parameter in the forecast results, allowing its applicability to other species. The results indicate a positive trend towards this principle, however, studies with larger sample intensity are required in order to achieve this correlation. Other applications may benefit from this line of study, such as the prediction of falling trees risks.

There is growing evidence that the achievement of biodiversity conservation objectives at the regional scale will have to take into account not only habitats within reserves, but also the contribution of semi-natural habitats in production landscapes. This requires knowledge of the conditions that maintain or enhance biodiversity in these suboptimal habitats. I focused on a system of forest patches and hedgerows in an agricultural landscape as habitats for dispersal-limited native forest herbs to (1) identify species-specific traits that appear to either limit or facilitate survival or colonization of forest herbs in hedgerows compared to forest patches, and (2) to evaluate the relative contribution of landscape and local variables in explaining patterns of forest herb species richness, abundance, and diversity in hedgerows. A fourth-corner analysis revealed that traits such as early spring flowering, ant dispersal or a lack of vegetative propagation can reduce the likelihood of native forest species to benefit from hedgerows. Conditional autoregressive models showed that landscape variables, specifically hedgerow age and neighboring forest area, largely account for species diversity in hedgerows.

Thesis (MScFor)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: The windbreak species near Wolseley (WoSl and WoS3) was Casuarina cunninghamiana. The windbreak species near Saron (SaSl) and Villiersdorp (ViSl) was Eucalyptus cladocalyx and Pinus radiata respectively. A shelter effect was indicated at ViSI (from northerly winds in winter/early spring 1999), and WoS3 (from southerly winds in late spring 1999). Wind speeds were consistently reduced in the leeward sheltered zone ofViSl and WoS3. To improve the correlation of the shelter effect, mild contaminating winds (comprising approximately 28% of the total data recorded at each site) were excluded for the prediction equations of the shelter effect at each site. Compared to the more exposed wind speeds at 1.0 H to the windward side, wind speeds at ViS] were reduced by 32% at 3.0 H. Compared to 11.0 H, wind speeds at ViSl were reduced by 49 and 46% at 3.0 and 1.0 H respectively. With r2 values above 93%, accurate linear prediction equations were produced. The early barley damage assessments indicated that damage was absent or negligible at 11.1 H to the lee, and significantly highest (X < 0.05) at 13.7 H to the lee and beyond. The crop shelter effect significantly increased (p < 0.05) barley head number, transformed proportion of total barley head mass from above-ground mass, potato tuber mass, potato above-ground mass total potato tuber number, small tuber number, and disproportionate tissue damage to the windward section of each plant. For WoS3, the shelter effect became pronounced with severe south-easterly winds. The average hourly wind speeds at 3.0 H dropped from 0.9 m / s (in the previous and less windy sampling period) to 0.8 m / s, despite the sharp increase in exposed wind speeds. Compared to 13.0 H, wind speeds were reduced by 73 and 32% at 3.0 and 7.0 H respectively. With r2 values above 94%, accurate linear prediction equations were produced. The crop shelter effect significantly increased (p < 0.05) sub-sample mass of lOO grains. At WoS3, strong and sustained wind speeds caused leeward soil temperature increases of up to 4°C at 3.0 H, compared to 11.0 H. Brief strong winds (characteristic of winds at ViSl) had little effect on the soil temperature differences. At ViSl, a deviation of soil moisture content between 3.0 and 11.0 H, following periods of recharge, indicated a potential soil-moisture conservation effect in the sheltered zone. This did not occur at WoS3, due partly to a very low soil moisture content that had little scope for variation; From the crop variations and the microclimate variations at both ViS 1 and WoS3, the maximum shelter effect extended to approximately 4.0 H, followed by an intermediate zone of diminishing shelter that extended to approximately 9.0 H. For ViSl, WoS3 and SaSl, a shading effect significantly reduced yields (p<0.05) at 1.0 H from the respective northern windbreak, compared to yields at 2.0 H. At ViS 1 and WoS3, soil probes did not indicate a depletion of soil moisture resulting from the respective windbreaks. Soil moisture competition was indicated on the northern side of the WoSl windbreak with drier conditions; where soil moisture levels at 1.0 and 3.0 H diverged from a negligible level to a 22% lower level (p > 0.05) at 1.0 H, compared to 3.0H. / AFRIKAANSE OPSOMMING: Die boomsoorte wat as windbreke gedien het was Casuarina cunninghamiana naby Wolseley (WoS 1 en WoS3), en Eucalyptus cladocalyx en Pinus radiata by Saron (SaS 1) en Villiersdorp (ViS 1) respektiewelik. Beskutting is aangetoon by ViS 1 (teen noordelike winde in winter/vroee lente 1999) en WoS3 (teen suidelike winde in laat lente 1999). Windspoed is konsekwent aan die lykant sones van ViS 1 en WoS3 verminder. Ten dien einde die korrelasie van die beskuttings effek te verbeter, is matige kontaminerende winde (ongeveer 28% van die totale waargenome data by elke plek) buite berekening gelaat vir die voorspellingsvergelykings van die beskuttingseffek. In vergelyking met die meer blootgestelde windspoede by 1.0 H aan die windkant, is windspoede by ViSl met 32% verminder by 3.0 H. In vergelyking met 11.0 H is windspoede by ViSl met 49 en 46% by 3.0 en 1.0 H respektiewelik verminder. Met r2 waardes hoer as 93%, is akkurate lineere voorspellingsvergelykings verkry. Die vroee gars skade opnames het aangetoon dat geen of minimale skade by 11.1 H aan die lykant aangerig is, en beduidend die hoogste (x< 0.05) by 13.7 Hen verder aan die lykant was. Die gewas beskuttins effek het beduidende toenames (p< 0.05) in garsare, getransformeerde verhouding van totale gars-are massa van bo-grondse massa, aartappelknol massa, aartappel bo-grondse massa, totale aantal aartappeiknolle, en oneweredige weefsel beskadiging aan die windkant van elke plant tot gevolg gehad. Vir WoS3 het die beskuttingseffek beduidend geword met baie sterk suidoostelike winde. Die gemiddelde uurlike windsnelhede by 3.0 H het van 0.9/ (in die vorige en minder winderige toetstydperk) tot 0.8 m/" verminder, ten spyte van die skerp toename in blootgestelde windsnelhede. In vergelyking met 13.0 H is windsnelhede met 73 en 32% by 3.0 en 7.0 H respektiewelik verrninder. Met r2 waardes hoer as 94% 15 akkurate lineere voorspellingsvergelykings verkry. Die gewas beskuttingseffek het sub-monster massa van 100 graankorrels beduidend (p< 0.05) verbeter. By WoS3 het sterk en volgehoue windsnelhede grondtemperature aan die lykant met tot 4°C by 3.0 H verhoog in vergelyking met 11.0 H. Kortstondige sterk winde (tipiese winde by ViS1) het weinig uitwerking op grondtemperatuursverskille gehad. By ViS1 het 'n afwyking van grondwaterinhoud tussen 3.0 en 11.0 H na tydperke van aanvulling, 'n potensiele grondwaterbewaringseffek in die beskutte gebied getoon. Soortgelyke tendense het nie by WoS3 voorgekom nie, gedeeltelik as gevolg van 'n baie lae grondwater inhoud wat nie veel kon varieer nie. Van die variasies wat in gewasse en mikroklimaat voorgekom het, by beide ViSl en WoS3, kan afgelei word dat maksimum beskutting tot by ongeveer 4.0 H verleen is, gevolg deur 'n intermediere sone van verminderende beskutting tot ongeveer 9.0 H. Vir ViS1, WoS3 en SaSl het 'n skadu-effek gewasopbrengs beduidend (p< 0.05) by 1.0 H verminder in vergelyking met opbrengste by 2.0 H. By ViS 1 en WoS3 het grondwater strooiingspeilers nie 'n uitputting van grondwater as gevolg van die windbreke getoon nie. Kompetisie vir grondwater is getoon aan die noordelike kant van die WoS1 windbreek met droer toestande. Grondwatervlakke by 3.0 H het minimaal maar by 1.0 H met 22% beduidend (p> 0.05) teenoor 3.0 H gedaal.