Arctic air temperatures have increased at two to three times the global rate over the past century. As a result, abiotic and biotic responses to climate change are more rapid and pronounced in the Arctic compared to other biomes. One important change detected over the past several decades by satellite studies is a lengthening of the arctic growing season, which is due to earlier onsets and/or delayed ends to growing seasons. A handful of studies also suggest the peak green season (i.e. when the tundra is at maximum leaf-out and maximum carbon uptake potential) is starting earlier in the arctic tundra. The vast majority of studies detecting shifts in the growing season suggest this is due to increasing spring and fall air temperatures, which lead to earlier spring snowmelt and later fall snowfall. Less well understood is how indirect consequences of arctic warming, such as ongoing changes in plant community composition, may also be contributing to these satellite signals. For instance, there is mounting evidence that deciduous shrubs are expanding into previously non-shrub dominated tundra in several parts of the Arctic. Deciduous shrubs may alter tundra canopy phenology and contribute to the regional shifts in timing of phenological events being detected by satellites. Concurrently, in many areas where deciduous shrubs are expanding they are also becoming taller. As taller shrubs become increasingly dominant, arctic landscapes may retain more snow, which could lengthen spring snow cover duration, and offset advances in the start of the growing season that are expected as a result of earlier spring snowmelt. As a consequence, deeper snow and later snowmelt in taller shrub tundra could delay plant emergence, and shorten the period of annual carbon uptake. Thus greater dominance of taller stature deciduous shrubs in the Arctic may actually delay the onset of the growing season, which would suggest that increasing deciduous shrub dominance may not be contributing to satellite signals of an earlier start to the growing season. To contribute to satellite-detected shifts in the onset of the growing and peak seasons, tall deciduous shrubs would need to have accelerated leaf development to compensate for deeper snow packs and later spring snowmelt relative to surrounding tundra. Understanding the drivers of shifts in tundra phenology is important since longer (or shorter) growing and peak green seasons would increase (or decrease) productivity and the period of carbon uptake, which will have implications for landscape-level carbon exchange, and ultimately global carbon balances. Given the rate and magnitude of changes occurring in the face of acute arctic warming, there is a need to monitor, understand, and predict ecological responses over large spatial and temporal scales. However, compared to more southern environments, the arctic tundra is characterized by considerable heterogeneity in vegetation distribution, as well as a short and rapid growing season. In addition, the arctic tundra is relatively vast and inaccessible. These characteristics can make it difficult to monitor and study changes in the Arctic, and make it difficult to develop landscape-level models able to predict changes in ecosystem dynamics and tundra vegetation. The use of airborne and satellite sensors has at least partially fulfilled these needs to monitor, understand, and predict change in the Arctic. The normalized difference vegetation index (NDVI) acquired from these sensors, for instance, has become a widely adopted tool for detecting and quantifying spatial-temporal dynamics in tundra vegetation cover, productivity, and phenology. This suggests that remote sensing technology and vegetation indices may be similarly applied to characterizing patterns of primary and secondary consumers (e.g. arthropods), which would be enormously useful in a region as vast and remote as the Arctic. The research presented in this dissertation provides useful insight into the influence vegetation community composition, particularly increasing deciduous shrub dominance, has on phenology, carbon flux, and canopy arthropod biomass in the arctic foothills region of the Brooks Range, Alaska. Findings in Chapter one suggest that delayed snowmelt in areas dominated by taller shrubs may have a short-lived impact on the timing of leaf development, likely resulting in no difference in duration of peak photosynthetic period between tall and short- stature shrubs. Findings in Chapter two suggest that greater deciduous shrub dominance not only increases carbon uptake due to higher leaf area relative to surrounding tundra, but may also be causing an earlier onset of, and ultimately a net extension of, the period of maximum tundra greenness and further increasing peak season carbon sequestration. Findings in Chapter three suggest that measurements of the NDVI made from air and spaceborne sensors may be able to quantify spatial and temporal variation in canopy arthropod biomass at landscape to regional scales in the arctic tundra.

L’anticipation des effets des changements climatiques nécessite une bonne compréhension dufonctionnement carboné des écosystèmes continentaux. L’une des principales contraintes liées àl’étude de ces écosystèmes est la forte variabilité à la fois spatiale et temporelle de leurs flux decarbone et de leurs réponses aux contraintes abiotiques. L’usage de méthodes de télédétectionoptiques pourrait permettre de suivre de façon spatialisée le fonctionnement des couverts végétaux.Ce travail vise à évaluer le potentiel de méthodes de télédétection pour décrire la structure et lefonctionnement de couverts végétaux à des échelles spatiales et temporelles variées. Pour ce faire,les relations entre indices optiques et phénomènes biologiques ont été étudiées en suivant unedémarche de transfert d’échelle, des échelles les plus fines aux plus larges. Il a été montré que le PRI(Photochemical Reflectance Index), utilisé en tant qu’indicateur du LUE (Light Use Efficiency), est parnature un signal composite qui reflète principalement la régulation du rendement de laphotosynthèse sur des échelles de temps fines, et la structure et composition biochimique ducouvert à l’échelle de la saison. L’analyse de courbes de réponse du PRI au PAR (PhotosyntheticallyActive Radiation) a permis de déconvoluer ces deux sources de variabilité, via l’introduction duconcept de PRI0 ou PRI d’une feuille idéalement adaptée à l’obscurité. Ce PRI0, capturant la variabilitédu PRI indépendante du LUE, a pu être mesuré à l’échelle de la feuille, et estimé à l’échelle de jeunescouverts végétaux et de la parcelle. Cette variabilité a pu être expliquée à l’échelle de la feuille et dejeunes couverts végétaux par les variations du contenu en pigment des feuilles. A l’échelle depeuplements adultes et de l’année, elle résulte cependant d’effets combinés de la compositionbiochimique et de la structure des couverts qui n’ont pu être séparés. Ces effets sont susceptiblesaux échelles larges de masquer en bonne partie, voire de biaiser la relation entre PRI et LUE. Il a enoutre été montré que la représentativité du PRI est limitée aux strates supérieures des canopées etdépend de la structure du couvert et du climat lumineux, ce qui peut limiter son intérêt en tantqu’estimateur du LUE à l’échelle de l’écosystème. Ces résultats soulignent la nécessité de prendre encompte la structure et la composition biochimique des couverts végétaux dans le cadre d’uneutilisation du PRI en tant que proxy du LUE de l’écosystème. / In order to assess the effect of global warming, a good understanding of carbon functioning ofterrestrial ecosystems is needed. The study of terrestrial ecosystem carbon fluxes and responses toabiotic stress remain challenging due to their high spatial and temporal variability. The use of remotesensing may help us to describe those sources of variability. The aim of this work is to assess thepotential of remote sensing as a way to describe canopy structure and functioning over a broadrange of temporal and spatial scales. The relationships between optical indices and biologicalphenomenon were investigated over a range of increasing scales. The PRI (PhotochemicalReflectance Index), used as a proxy of the LUE (Light Use Efficiency) was shown to be a compositesignal, mainly impacted by the regulation of the LUE at short time scales, and by canopy structureand pigment content at seasonal scale. The analysis of PRI response to PAR (PhotosyntheticallyActive Radiation) allowed us to deconvolve those two sources of variability thanks to theintroduction of the PRI0 defined as the PRI of ideally dark adapted leaves. The PRI0 was shown toefficiently describe the LUE unrelated PRI variability, and could be measured at leaf scale, andestimated at the leaf, canopy and stand scales. This variability could be explained by changes in leafpigment content over the growing season at leaf and canopy scales. At the stand scale and over theyear, this LUE independent PRI variability resulted from combined effects of canopy structure andpigment content, which could not be separated. These effects may result in biased or masked PRIversus LUE relationships at larges scales. Moreover, it was shown that the in-situ PRI measurementsmainly responded to the LUE of sunlit leaves, depending on canopy structure and sky conditions. Thismay considerably hamper the use of the PRI as a proxy of the whole ecosystem LUE. These resultsillustrate the need to take canopy structure and pigment content into account while using the PRI asa proxy of the ecosystem LUE.

Les régions alpines sont particulièrement sensibles aux changements climatiques en cours. Ainsi, l’ouest des Alpes s’est réchauffé deux fois plus vite que l’hémisphère Nord au cours du XXème siècle. Les rythmes saisonniers des arbres, comme beaucoup d’autres organismes, sont fortement modifiés par le réchauffement climatique. La phénologie et les variations temporelles fines du climat apparaissent comme des composantes incontournables à prendre en compte pour prédire la répartition des espèces. L’objectif principal de ce travail de thèse a été de comprendre la réponse de la phénologie des espèces arborées au réchauffement climatique dans les Alpes et de développer des outils pour évaluer cette réponse dans le futur. Pour atteindre cet objectif nous avons utilisé des données phénologiques (débourrement, floraison, senescence foliaire,) pour le noisetier, le frêne, le bouleau, le mélèze et l’épicéa, issues du programme de sciences participatives Phénoclim.Nos résultats montrent que le réchauffement de l’hiver retarde la levée de la dormance des bourgeons et par conséquent les dates de débourrement et de floraison le long du gradient d’altitude. Cet effet est plus important à basse altitude. La robustesse des projections des modèles de répartition basés sur les processus dépend fortement de la robustesse des modèles phénologiques qu’ils utilisent. En comparant des modèles phénologiques présentant différents niveaux de complexité nous avons montré que les modèles basés sur les processus étaient les plus robustes particulièrement lorsque l’estimation de leurs paramètres reposait sur une estimation directe à l'aide de mesures expérimentales. Les modèles prévoient une réduction des écarts entre les dates de débourrement le long du gradient d'altitude pour toutes les espèces d'ici la fin du 21e siècle. Ceci est dû d’une part à un avancement des dates de débourrement à haute altitude et d’autre part à un retard des dates de débourrement à basse altitude. Nous avons également testé de nouvelles hypothèses sur le déterminisme environnemental de la croissance cellulaire dans les bourgeons, mais aucune des hypothèses testées n’a significativement amélioré les performances des modèles. Nous avons ensuite intégré les modèles phénologiques les plus performants que nous ayons obtenus au modèle d’aire de répartition basé sur les processus PHENOFIT. Nous avons réalisé pour la première fois avec ce modèle des simulations à haute résolution spatiale. Les projections du modèle montrent que les espèces arborées devraient se déplacer vers le haut du gradient d’altitude. Cependant, des phénomènes d’extinction locale pourraient avoir lieu dans les fonds des vallées liés à des dates de floraison trop tardives qui diminuerait le succès reproducteur des individus. Selon les espèces, la limite altitudinale supérieure serait contrôlée par le risque d'exposition au gel tardif des fleurs ou par la longueur de la saison de croissance qui détermine le temps disponible pour la maturation des fruits.L’ensemble de ces résultats nous a permis d’apporter des éléments de réponse sur la dynamique future des écosystèmes forestiers altitudes face au réchauffement climatique. Ils nous ont également permis de montrer que les données du programme Phénoclim étaient de qualité suffisante pour être utilisées dans des travaux de recherche scientifique. / Mountainous regions are particularly exposed to the ongoing climate change. Indeed, in the Western Alps the temperature increased twice faster than in the northern hemisphere during the 20th century. Trees’ annual cycle, as in many other organisms, is largely affected by climate change. Phenology and the fine temporal variations of climate appear key to predict species distribution. The main objective of this PhD thesis work was to understand the response of tree phenology to climate change in the Alps and to develop tools to evaluate this response in future conditions. It has been carried out using the phenological observations (budburst, flowering, leaf senescence) of five tree species (hazel, ash, birch, larch and spruce) of the citizen science program Phenoclim.Our results show that warmer winters slow down bud dormancy break, and consequently the budburst and flowering dates along the elevation gradient. This effect is stronger at low elevation. The robustness of process-based species distribution models depends strongly on the robustness of their process-based phenology sub-model. By comparing different phenology models differing in their level of complexity and we showed that process-based models were the most robust especially when their parameter estimates relied on forward estimation using experimental data. Models project a reduction in the phenological cline along the elevation gradient by the end of the 21th century. This is due, on one hand, to an advancement of the budburst dates at high elevation and on the other hand, to a delay of the budburst dates at low elevation. We also tested several hypotheses on the environmental determinism of bud cell growth. However, none of the hypotheses improved significantly the models’ performance. We then implemented the best phenology models we obtained in the process-based species distribution model PHENOFIT. We carried out for the first time simulations at high spatial resolution. Projections showed that species are expected to move up along the elevation gradient in response to climate change. However, local extinction events may occur in the bottom of the valleys due to late flowering dates that would decrease the reproductive success. Depending on the species, the upper altitudinal limit would be controlled by the risk of flowers’ exposure to late spring frost or to the length of growing season, which determine fruit maturation success.All of these results, allowed us to provide some answers on the future dynamics of high altitude ecosystems in the face of global climate change. They also allowed us to show that the Phenoclim data were of sufficient quality to be used to address important scientific questions.

A palmeira juçara – Euterpe edulis Mart. (Arecaceae) – é uma espécie abundante nas florestas onde ocorre e que produz grande quantidade de flores e frutos, sendo assim de grande importância ecológica. Após décadas de desmatamento e superexploração do palmito, as populações encontram-se reduzidas a fragmentos. Este trabalho teve como objetivo estudar alguns aspectos etnoecológicos e ecofisiológicos acerca da espécie. Foram verificados cinco sistemas de manejo desenvolvidos por comunidades locais do litoral norte do Rio Grande do Sul: manejo em capoeiras, manejo em reflorestamentos com espécies exóticas, manejo em bananais, quintais agroflorestais e corte clandestino de palmito em florestas. Comparou-se o crescimento de palmeiras jovens em florestas secundárias e bananais, de 2003 a 2008, e verificou-se que o tamanho das palmeiras em 2008 nos bananais foi cinco vezes maior do que nas florestas, apesar da herbivoria ter sido maior nos bananais; a mortalidade foi equivalente entre os dois tratamentos, apesar da grande variabilidade, e apresentando um padrão intraespecífico dependente da densidade. Observou-se um padrão de variação dos eventos fenológicos reprodutivos associado a latitude e altitude; verificou-se também uma relação quadrática significativa entre épocas de floração e de maturação dos frutos, demonstrando que o tempo necessário desde a floração até a maturação dos frutos depende da época que ocorre a floração. Verificou-se que os sistemas de manejo são diferentes estratégias de uso da juçara, e que esta apresenta um grande potencial para manejo. / The juçara palm - Euterpe edulis Mart. (Arecaceae) - is an abundant species in the forests where it occurs and that produces lots of flowers and fruits, being of great ecological importance. After decades of deforestation and heart of palm exploitation, it is reduced to fragments. This work aimed to study some ethnoecological and ecophisiological aspects of this species. We observed five management systems developed by local communities of the northern coast of Rio Grande do Sul: management in early secondary forest, management in reforestation with exotic species, management in banana plantations, homegardens and illegal cutting in forests. We compared the growth of young palms in secondary forests and banana plantations from 2003 to 2008, and found that the size of palms in 2008 in banana plantations was five times greater than in forests, in spite of herbivory was higher in the banana plantations; the mortality was equivalent between the two treatments, despite the great variability, and presenting an intraspecific density-dependent pattern. There was a pattern of variation in reproductive phenology related to latitude and altitude; there was also a significant quadratic relationship between timing of flowering and fruit ripening, showing that the time required from flowering to fruit maturity depends on the time the flowering occurs. It was found that the management systems are different strategies of use of the juçara palm, and that this species has high potential for management.

Made available in DSpace on 2014-06-11T19:30:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-10-26Bitstream added on 2014-06-13T19:19:47Z : No. of bitstreams: 1 castro_er_dr_rcla.pdf: 1176380 bytes, checksum: 2458a65ca174e407c9be76f8a7548b6d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O palmito Euterpe edulis é uma das espécies de árvores dominates na Floresta Atlântica, e seus frutos constituem uma parte importante da dieta de várias espécies de aves frugívoras. O presente estudo foi desenvolvido em três tipos de Floresta Atlântica (restinga, planície e encosta), na Ilha do Cardoso (Cananéia, São Paulo), durante três anos de observação. Os objetivos foram (1) comparar a fenologia reprodutiva do palmito nos três tipos florestais, e determinar quais os fatores ambientais que estariam influenciando os padrões encontrados; (2) estudar a oferta de frutos e consumo dos mesmos pelas aves frugívoras (em particular, duas espécies de aves Turdus flavipes e Turdus albicollis), e avaliar a relação da abundância destas aves com a oferta de frutos da comuniade arbórea e do palmito E. edulis. Nós avaliamos o consumo de frutos das aves e monitoramos a fenologia de frutificação do palmito e da comunidade arbórea nos três tipos florestais, comparando mensalmente com os dados de censo das aves, de agosto 2001 a julho 2004. Nós também estimamos no mesmo período à produção de frutos e sementes coletados no chão da floresta para o palmito e para a comunidade arbórea. A fenologia de frutificação do palmito foi anual e sazonal nos três tipos florestais, com as fases fruto imaturo e verde correlacionadas com o comprimento do dia, precipitação, e temperaturas, importantes fatores para o desenvolvimento dos frutos. A biomasa de frutos e sementes de palmito coletados no chão diferiram significativamene entre os tipos florestais, sendo maiores estas diferenças entre as florestas restinga e planície. Estas diferenças na produtividade foram relacionadas a densidade do palmito em cada área e a fertilidade de solo. Sobre a dieta das aves... / The palm Euterpe edulis is one of the most common species in Atlantic Brazilian Tropical Rainforest, and its fruits are an important part on the diet of several frugivorous birds' species. This study had been developed in three Atlantic Rainforest types (restinga, lowland and premontane), located in Cardoso Island (Cananéia, São Paulo state), during three years of study. The objectives were: (1) to compare the reproductive phenology of the palm in three forest types, determining which environmental factors could be affecting the patterns found; (2) to study the available number of fruits and the consume of them by the frugivorous birds (mainly, two birds species Turdus flavipes and Turdus albicollis), and to evaluate the abundance relation of these birds with the available number of fruits in the arboreal community and the palm E. edulis. The fruits consume of the birds had been evaluated, and the reproductive phenology of the palm as well the arboreal community in the three types of forest had been monitored. The bird's census data had been compared from August 2001 to July 2004. The palm and the arboreal community production of fruits and seeds taken on the ground of the forest had been estimated during the same period. The reproductive phenology of the palm was annual and seasonal in the three types of forest, having its unripe fruit phases co-related to the day length, precipitation, and temperatures which are important aspects to the fruit development. The palm fruit and seed biomass taken on the ground of the forest differs meaningfully within the forest types, such difference is bigger when considered the restinga and lowland forest. This productivity differences were related to the palm density in each area and the soil fertility. About the bird s diet, 600 records of feeding had been observed, and the families which got the biggest... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:30:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-17Bitstream added on 2014-06-13T20:21:34Z : No. of bitstreams: 1 souza_lf_dr_rcla.pdf: 761890 bytes, checksum: 167f9e1992570e32764d25441f593676 (MD5) / O Cerrado é a maior savana da América do sul, situando-se principalmente no Brasil, com área core no Planalto Central, abrangendo 97% do estado de Goiás. O Cerrado está desaparecendo em ritmo acelerado, com baixo percentual de reservas e, entre estas, muitas se encontram pouco pesquisadas. Portanto, conduziu-se o presente trabalho na Reserva Pousada das Araras com o objetivo estudar as formações vegetais para averiguar se a riqueza de fitofisionomias, riqueza e diversidade de espécies fanerogâmicas e a razão entre os componentes da vegetação (arbóreo/arbustivo e subarbustivo/herbáceo) são iguais àquelas descritas para o Cerrado. Objetivou também analisar se os padrões fenológicos reprodutivos das formações e dos componentes da vegetação comportam-se como em outras comunidades do bioma. Este trabalho considera que 10% da Reserva é uma RPPN, Área de Proteção Ambiental (APA) situada no entorno de uma Unidade de Conservação (Parque Nacional das Emas), presumivelmente uma área com riqueza e diversidade significativas, bem como estratégias fenológicas semelhantes às da maioria das comunidades do bioma, refletindo a sua conservação. A área de estudos localiza-se na região core do Cerrado, Planalto Central do Brasil, estado de Goiás, microrregião sudoeste, município de Serranópolis, coordenadas 51º59’42”-52º00'22W, 18º26'33-10S. As coletas de dados foram realizadas no período de maio de 2004 a junho de 2006. Os tipos de vegetação foram identificados utilizando imagem aérea, GPS e visualmente observando o hábito dos indivíduos, % de caducifolia e cobertura, luminosidade, formação de dossel, presença de estratos, proximidade de corpos d’água, afloramentos rochosos e a flora local. As amostras vegetais férteis foram coletadas de forma usual, numeradas herborizadas, triadas, identificadas e depositadas no Herbário Jataiense Germano Guarim Neto... / The Cerrado is the largest savanna area from South America, mainly situated in Brazil, with core area in the Planalto Central, encircling 97% of Goias State. The Cerrado is disappearing in accelerated rhythm, with reservations percentile and among these many of them are not researched. Therefore, this work was conducted in Reserva Pousada das Araras aiming to study the vegetal formations to investigate if the richness of phytophysiognomy, richness and diversity of phanerogamic species and the reason between the components of the vegetation (arboreal/shrub and sub-shrub/herbaceous) are similar to those described for the Cerrado. This study also aimed to analyze if the reproductive phenological standards of the formation and the vegetation components behave them as in other communities of the biome. This study considers that 10% of the reservation is an RPPN, Environmental Protection Area (APA) situated around a preservation unit (Parque Nacional das Emas), presumably an area with significant richness and diversity as well as similar phenological strategies to the most communities of the biome, reflecting its conservation. The area of the studies is located in the core region of the Cerrado, Planalto Central of Brazil, Goias State Southwest micro region in the municipality of Serranópolis, coordinates 51°59’42”00’22”W, 18°26’33”-10”S. The data collects were realized in the period from May 2004 to June 2006. The types of vegetation were identified by utilizing aerial image, GPS and visually by observing the habits of the individuals, percentile of leaves fall and coverage, luminosity, dossel formation, presence of strata, proximity of water corps, rocky outcrops and local flora. The fertile vegetal samples were collected by a usual way, numbered, herborized and selected, identified and deposited in the Germano Guarim Neto herbarium from Jataí (HJ). The taxons were identified... (Complete abstract click electronic access below)

Resumo: O palmito Euterpe edulis é uma das espécies de árvores dominates na Floresta Atlântica, e seus frutos constituem uma parte importante da dieta de várias espécies de aves frugívoras. O presente estudo foi desenvolvido em três tipos de Floresta Atlântica (restinga, planície e encosta), na Ilha do Cardoso (Cananéia, São Paulo), durante três anos de observação. Os objetivos foram (1) comparar a fenologia reprodutiva do palmito nos três tipos florestais, e determinar quais os fatores ambientais que estariam influenciando os padrões encontrados; (2) estudar a oferta de frutos e consumo dos mesmos pelas aves frugívoras (em particular, duas espécies de aves Turdus flavipes e Turdus albicollis), e avaliar a relação da abundância destas aves com a oferta de frutos da comuniade arbórea e do palmito E. edulis. Nós avaliamos o consumo de frutos das aves e monitoramos a fenologia de frutificação do palmito e da comunidade arbórea nos três tipos florestais, comparando mensalmente com os dados de censo das aves, de agosto 2001 a julho 2004. Nós também estimamos no mesmo período à produção de frutos e sementes coletados no chão da floresta para o palmito e para a comunidade arbórea. A fenologia de frutificação do palmito foi anual e sazonal nos três tipos florestais, com as fases fruto imaturo e verde correlacionadas com o comprimento do dia, precipitação, e temperaturas, importantes fatores para o desenvolvimento dos frutos. A biomasa de frutos e sementes de palmito coletados no chão diferiram significativamene entre os tipos florestais, sendo maiores estas diferenças entre as florestas restinga e planície. Estas diferenças na produtividade foram relacionadas a densidade do palmito em cada área e a fertilidade de solo. Sobre a dieta das aves... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The palm Euterpe edulis is one of the most common species in Atlantic Brazilian Tropical Rainforest, and its fruits are an important part on the diet of several frugivorous birds' species. This study had been developed in three Atlantic Rainforest types (restinga, lowland and premontane), located in Cardoso Island (Cananéia, São Paulo state), during three years of study. The objectives were: (1) to compare the reproductive phenology of the palm in three forest types, determining which environmental factors could be affecting the patterns found; (2) to study the available number of fruits and the consume of them by the frugivorous birds (mainly, two birds species Turdus flavipes and Turdus albicollis), and to evaluate the abundance relation of these birds with the available number of fruits in the arboreal community and the palm E. edulis. The fruits consume of the birds had been evaluated, and the reproductive phenology of the palm as well the arboreal community in the three types of forest had been monitored. The bird's census data had been compared from August 2001 to July 2004. The palm and the arboreal community production of fruits and seeds taken on the ground of the forest had been estimated during the same period. The reproductive phenology of the palm was annual and seasonal in the three types of forest, having its unripe fruit phases co-related to the day length, precipitation, and temperatures which are important aspects to the fruit development. The palm fruit and seed biomass taken on the ground of the forest differs meaningfully within the forest types, such difference is bigger when considered the restinga and lowland forest. This productivity differences were related to the palm density in each area and the soil fertility. About the bird’s diet, 600 records of feeding had been observed, and the families which got the biggest... (Complete abstract click electronic access below) / Orientador: Mauro Galetti / Coorientador: Leonor Patrícia Cerdeira Morellato / Banca: Sandra Bos Mikich / Banca: Adelar Mantovani / Banca: Mercival Roberto Francisco / Banca: Valesca Bononi Ziparro / Doutor

Em 2007 o complexo de soja foi responsável por 19 por cento do total das exportações do agronegócio brasileiro, gerando mais de U$11 bilhões em divisas. Projeções indicam que até 2020 o Brasil deverá produzir 105 milhões de toneladas de soja, ou 81 por cento a mais do que a atual produção. Apesar de incidir sobre a produtividade a maior expectativa de crescimento, espera-se que a expansão significativa em área ocorra nas regiões de baixa latitude dos Cerrados, e em especial, no estado do Mato Grosso. É fundamental a determinação de estratégias que considerem produção, dimensões econômicas e ambientais. O uso da modelagem agrícola é a única forma de explorar sistematicamente o potencial produtivo em escala global e predizer produtividades futuras em determinadas condições. A utilização de computadores e banco de dados torna-se uma ferramenta cada vez mais necessária, no sentido de disponibilizar rapidamente informações de qualidade a um custo relativamente inferior, quando em comparação a experimentos de campo. O modelo LINTUL, desenvolvido pela Universidade de Wageningen, foi extensamente utilizado para predizer a produtividade potencial de culturas baseado no uso eficiente da radiação solar, sob condições ótimas de desenvolvimento. A cultura de soja, porém, nunca foi testada por este modelo. Sendo assim, os objetivos deste trabalho foram: (i) adaptação, por intermédio da parametrização e da calibração do modelo LINTUL para estimação da produtividade potencial da cultura de soja; (ii) disponibilizar um algoritmo em Visual Basic (Microsoft), validando e replicando os procedimentos do LINTUL, tornando este modelo acessível a uma ampla gama de usuários. Para a parametrização do modelo, foram consideradas características específicas da cultura, como por exemplo, a sensibilidade ao fotoperíodo. Para calibração, foram usados dados de experimento de campo conduzido em Planaltina-DFe Sorriso- MT. Os parâmetros não avaliados no experimento foram extensivamente revisados com base na literatura. Os principais componentes do processo de crescimento e desenvolvimento da cultura foram analisados individualmente através de comparativos de respostas. Posteriormente, um estudo de adequação do modelo foi feito, com objetivo de viabilizar uma comparação de comportamentos, quando em diferentes situações. As variáveis climáticas usadas neste modelo foram temperatura máxima e mínima e radiação solar. A simulação dos estádios fenológicos é baseada na soma térmica. O modelo LINTUL-soja demonstrou excelente desempenho quanto à predição de tendências, com a variação dos valores dos parâmetros. Todavia, o modelo necessita de ajustes quanto a introdução de módulos, que contemplem o balanço de carboidratos. O uso de uma linguagem de programação aberta, como o Visual Basic, replicou a linguagem usada pelo modelo LINTUL com sucesso. / In 2007 the soybean complex was responsible for more than 19% of the total Brazilian agribusiness exports, which corresponded to US$ 11 billion generated in currencies. According to projections, soybean production in Brazil will increase significantly till 2020, reaching 105 million tons, or an addition of 81 percent to the current crop season. That huge difference is expected to come from a significant increase in yield, while the increase in acreage should come from the low-latitude regions of Cerrados, mainly in Mato Grosso state. Thus, it becomes extremely important to set out strategies that consider production, economic and environmental dimensions. The usage of agricultural modeling is the only mean of systematically exploring the production potential on global scale and predict future yield in certain conditions. Computers and database application becomes an implement even more efficient in respect of turn quickly and quality information available with lower costs, when compared to the field experiments. The LINTUL model was developed by the Wageningen University, and extensively used to predict crop potential production based on radiation use efficiency concept, under optimal conditions of growth. The soybean crop has never been tested by this model. The goals of this research are: (i) to adapt - through parameterizing and calibration - the LINTUL model to estimate the potential production of soybean; (ii) to provide an algorithm in Visual Basic language, in order to validate the calculations and replicate the procedures executed by LINTUL, making this model accessible to a wide range of users. In order to parameterize the model, crop-specific characteristics were taken into account, such as the sensibility of soybean to photoperiod. In respect to calibration, it was used field data collected in Planaltina-DF and Sorriso-MT. The mainly components of the growth and development process were analyzed based on response comparatives. Afterward, it was done a study of adequacy of the model, in order to enable a comparison of behaviors, when in different situations. The climatic variables used in this model were maximum and minimum temperature and solar radiation. The simulation of phenological stages was based on thermal unit concept. The LINTUL-soybean model has demonstrated an excellent performance to predict trends, with the change in the parameters values. However, the model needs to be adjusted in respect to an introduction module to calculate the carbohydrates balance into the canopy. The use of an open programming language, such as Visual Basic, replied the language used by LINTUL model successfully.

A nogueira macadâmia se apresenta como uma importante alternativa para a fruticultura paulista, principalmente pela sua rusticidade e pelo valor alcançado pelos seus frutos. No entanto, estudos relacionados ao seu desenvolvimento e às suas características produtivas são necessários para a adequada escolha da variedade a ser cultivada. Com o objetivo de caracterizar o desenvolvimento, a produção e a produção de mudas para diferentes cultivares de nogueira macadâmia para o clima Cwa, conduziu-se diferentes experimentos instalados no município de Dois Córregos SP: Emergência de plântulas de 8 cultivares de nogueira macadâmia; Emergência de plântulas do porta-enxerto Aloha para nogueira macadâmia em diferentes temperaturas; Emergência de plântulas de sementes nogueira macadâmia submetidas à incisão e imersão em ácido giberélico; Enraizamento de diferentes tipos de estacas do porta-enxerto Aloha para nogueira macadâmia, tratadas com ácido indolbutírico; Alporquia em ramos do porta-enxerto Aloha para nogueira macadâmia, realizada em diferentes épocas e tratadas com diferentes concentrações de ácido indolbutírico; Fenologia da floração de oito cultivares de nogueira macadâmia em clima Cwa; Desempenho produtivo e biometria de frutos de cultivares de nogueira macadâmia; Teor e composição de óleo de diferentes variedades de nogueira macadâmia. Os resultados mostraram que para essas condições a maior porcentagem de emergência de plântulas é obtida pela cultivar Campinas-B, assim como a maior massa seca da parte aérea e do sistema radicular; Para a cultivar Aloha, a maior emergência de plântulas é obtida com a temperatura de 27,5 C; A incisão e a imersão em ácido giberélico de sementes de nogueira macadâmia não trazem benefícios à emergência e desenvolvimento das plântulas; A maior porcentagem de enraizamento é obtida com a cultivar 4-12 B; Estacas com duas folhas inteiras apresentam maior porcentagem de enraizamento; Os melhores resultados para a alporquia da cultivar Aloha são obtidos em dezembro; Observouse 13 estádios fenológicos, com o entumescimento de gemas entre maio e junho, antese entre julho e agosto e queda de frutos entre fevereiro e março; A cultivar 816 apresenta os maiores valores para as variáveis diâmetro da noz e da amêndoa e massa da amêndoa; As cultivares 344, 1-21 e 4-12 B apresentam maior produção. Para a taxa de recuperação de amêndoa (TR), os melhores resultados são obtidos pelas cultivares 344, 660 e Aloha; As cultivares 660, 4-20 e 1-21 apresentam as maiores porcentagens de óleo e cultivar 344 apresenta óleo de melhor qualidade / The macadamia cultivation presents itself as an important alternative for fruit growers of the State of São Paulo, mainly because of its rusticity and the value reached by their fruits. However, studies related to their development and characteristics of production are essential for the correct choice of the variety to be cultivated. In order to characterize the development and the fruit and nursery trees production for different macadamia cultivars in the Cwa climate, different experiments have been carried out in the city of Dois Córregos, State of São Paulo: Seedling emergence of eight macadamia cultivars; Seedling emergence of macadamia rootstock Aloha at different temperatures; Seedling emergence from seeds treated with incision and immersion in gibberellic acid; Rooting of different types of cuttings of macadamia rootstock Aloha treated with indolbutyric acid; Air layering in branches of macadamia rootstock Aloha, done at different periods and treated with different concentrations of indolbutyric acid; Flowering phenology of eight macadamia cultivars in Cwa climate; Production performance and biometry of different macadamia cultivars and oil content and composition of different macadamia cultivars. The results have shown that under these conditions the highest percentage of seedling emergence was achieved by the cultivar Campinas-B, as well as higher dry mass of shoot and root system; Regarding the Aloha cultivar, the highest seedling emergence was achieved by a temperature of 27.5 C. The incision and immersion of seeds in gibberellic acid brought no benefits to the seedling emergence and development; The highest rooting percentage was obtained with the cultivar B 4-12; Cuttings with two leaves provided a higher rooting percentage; The best results for the air layering propagation were obtained on December; 13 phonology stages have been observed, with the swelling of buds between May and June, anthesis between July and August and fruit drop between February and March; The 816 cultivar presented the highest values for the nut and almond diameter and for the almond weight; Cultivars 344, 1-21 and 4-12 B had the biggest production. For the kernel recovery (KR) rate, the best results were obtained with cultivars 344, 660 and Aloha; Cultivars 660, 4-20 and 1-21 presented the highest oil percentages, and cultivar 344 the best oil quality.

O conhecimento das diferentes fases do ciclo básico de vida da espécie vegetal constitui uma ferramenta eficaz de manejo e que uma vez identificados possibilita alcançar boas produtividades e melhor qualidade ao produto comercial. O objetivo deste trabalho foi avaliar o desempenho produtivo e as características químicas da borracha de quatro clones de seringueira, sob diferentes sistemas de sangria, estádios fenológicos e condições edafoclimáticas. O experimento foi instalado na área experimental do Departamento de Produção Vegetal da Escola Superior de Agricultura Luiz de Queiroz, da ESALQ/USP, no município de Piracicaba, SP (2242`30``S, 4738`00``W) e na Agência Paulista de Tecnologia dos Agronegócios (APTA) - Pólo Regional do Desenvolvimento Tecnológico de Agronegócios do Noroeste Paulista, no município de Votuporanga, SP (20°20S, 49°50W). O delineamento experimental adotado foi o de blocos casualizados em esquema parcela subdividida com três ou quatro réplicas. Os tratamentos principais (clones GT 1, PB 235, IAN 873 e RRIM 600) foram alocados nas parcelas e os tratamentos secundários (sistemas de sangria: ½S d/2; ½S d/4 ET 2,5%; ½S d/7 ET 2,5%) constituíram as subparcelas. As variáveis analisadas foram: produção de borracha seca, teores de cinzas e de macronutrientes e micronutrientes da borracha natural. As amostras de borracha natural foram obtidas nos estádios fenológicos: refolhamento; folhas maduras e senescência de folhas. Concluiu-se que a produção e as características da borracha são influenciadas pelas condições edafoclimáticas, pelos sistemas de sangria dependendo do estádio fenológico. A produção e os teores de nutrientes são mais influenciados pela prática de sangria do que pelo material genético, no estádio de senescência e em condições restritivas para a planta. / The knowledge of the different phases of the basic life cycle of plant species is an effective tool of management and that once identified possible to obtain good yields and better quality to the commercial product. The objective of this work was to evaluate the yield performance and chemical characteristics of the rubber of four rubber tree clones under different tapping systems, phenological stages and edaphoclimatic conditions. The experiment was carried in experimental area of the Departamento de Produção Vegetal da Escola Superior de Agricultura Luiz de Queiroz, da ESALQ/USP, Brazil (2242`30``S, 4738`00``W) and in Agência Paulista de Tecnologia dos Agronegócios (APTA) - Pólo Regional do Desenvolvimento Tecnológico de Agronegócios do Noroeste Paulista, in Votuporanga city São Paulo State, Brazil (20 ° 20\'S, 49 ° 50\'W). The experimental design was in randomized block design with split plot and three or four replicates. The main treatments (GT 1, PB 235, IAN 873 and RRIM 600 clones) were allocated in the plots and secondary treatments (tapping systems: ½S d/2; ½S d/4 ET 2.5%; ½ S d/7 ET 2.5%) constituted the subplots. The analyzed variables were: dry rubber yield, ash content, macronutrients and micronutrients of the natural rubber. Samples of natural rubber were obtained in the phenological stages: leaves development, mature leaves and leaves senescence. It was concluded that the yield and chemical characteristics of the rubber are influenced by the edaphoclimatic conditions, by the tapping systems and depending of the phenological stages. The yield and nutrients content of natural rubber is more influenced by the tapping practice than the genetic material in the leaves senescence stage and under restrictive conditions for the plant.