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El sur de los Andes Ecuatorianos alberga una extraordinaria riqueza de especies. Muchos factores ambientales diferentes influyen entre sí en un espacio muy limitado y crean ecosistemas únicos y complejos. Sin embargo, esta área está altamente en peligro debido al creciente impacto humano a través de la intensificación del uso de la tierra y cambio global. Sólo poco se sabe acerca de la historia paleoecológica y dinámica del paisaje de esta zona. Sin embargo, la información acerca del por qué y cómo los ecosistemas han cambiado en el pasado es crucial para el desarrollo de estrategias innovadoras para la conservación y futuras predicciones del clima. En este estudio, presentamos los análisis palinológicos realizados en la región sur de los Andes Ecuatorianos, que ayudan aclarar los patrones y procesos de los ecosistemas presentes y pasados. El estudio paleoecológico de la cuenca volcánica Quimsacocha en la cresta oriental de la Cordillera Occidental revela cambios del clima, la vegetación y del régimen del fuego desde el período del Holoceno temprano. El Holoceno medio fue un período de severos cambios ambientales debido a un clima más seco y supuestamente más cálido en esta área. Durante el Holoceno tardío, varias fases cálidas y frías se indican en el registro. El fuego estuvo presente en la zona desde el Holoceno temprano y puede ser el primer signo del impacto humano. El análisis multivariado combinado con otros núcleos de sedimentos en el sur de los Andes Ecuatorianos reveló acontecimientos, en parte, contrastantes, los cuales supuestamente son debido a la heterogeneidad ambiental de los diferentes sitios. Por otra parte, un estudio de tres años entre la relación lluvia de polen actual – vegetación se llevó a cabo en la región del Parque Nacional Podocarpus, con el fin de comprender los patrones de dispersión de polen de los diferentes tipos de vegetación del bosque premontano, bosque montano bajo, bosque montano alto y páramo para crear una base más sólida para la interpretación de los datos de polen fósil. Una comparación entre la abundancia y los datos de presencia-ausencia a nivel de familia para el polen y la vegetación mostró que los patrones de diversidad, distribución y abundancia tienen una buena correspondencia el uno con el otro en ambos conjuntos de datos. Sin embargo, cantidades variables del polen transportado de larga distancia, la productividad desigual de polen de los diferentes taxones y los sistemas heterogéneos del viento impactan los patrones. Los análisis de las tasas de acumulación de polen indican poca variación interanual pero una alta variación espacial en los datos de polen. La evaluación de los dos diferentes tipos de trampa de polen utilizados con frecuencia en estudios palinológicos tropicales, la trampa Oldfield modificada y la trampa Behling, en comparación con muestras de suelo superficial y una trampa de referencia, mostró que en las muestras de suelo, los taxones con una exina frágil se representan en menor medida que en las trampas. Además, señaló que mientras que en el bosque, todos los tipos de trampas proporcionan resultados similares, la trampa Behling se debe preferir en el páramo, ya que resiste mejor a la alta radiación y periodos de sequía. Todos los análisis amplían el conocimiento preciso y completo de la dinámica de la vegetación de los Andes Tropicales en el espacio y el tiempo.

This diploma thesis ,,buckwheat attractivity for bees" deals mainly with native nectar plants for the processing of bees to honey. Work is folded in two parts. The theoretical part deals with the migration of colonies, both for nectar crops and plants with bee pollination needs. In ractical part of this thesis microscopic pollen analysis were performed and contents of pollen grains in honey from colonies, which were relocated to buckwheat growth was evaluated. Comparison of this honey with honey from the hives with similaar location, but without access to buckwheat growth was done.

Made available in DSpace on 2016-08-17T15:00:43Z (GMT). No. of bitstreams: 1 Dissertacao Gracy Chrisley Carvalho.pdf: 2155639 bytes, checksum: fdf1bfc985cd4dc0f7e767ea5d5107a7 (MD5) Previous issue date: 2014-05-13 / FUNDAÇÃO DE AMPARO À PESQUISA E AO DESENVOLVIMENTO CIENTIFICO E TECNOLÓGICO DO MARANHÃO / Knowing the diversity of solitary bees through trap-nests have sought to compose a checklist of diversity, as well as the account of the behavior and biology of the species. Few studies have been done in the state of Maranhão, which is a privileged area, as it includes within its boundaries the two major biomes. Given these few reports, the purpose of this work was to study the community of solitary bees by the method of trap nests for two years, in an area of cerrado and gallery forest, in the Parque Estadual do Mirador. Also, describe the nesting biology of Centris (Hemisiella) dichrootricha and analyze the floristic composition of the food of her offspring. The study area is located in the Parque Estadual do Mirador, municipality of Formosa Serra Negra, Maranhão. The method used was the trap-nests in wood diameters 6, 8, 10, 12, 14 and 16 mm, these were grouped in sets of 6 nests, totaling 300 nests per area. A total of 101 nests belonging was founded 11 bee species, including eight species occurred in the Gallery Forest and six in the Cerrado, and the similarity was low among habitats (SJ = 0.27). Two species were dominant in the community, Centris dichrootricha in Gallery Forest and the Centris tarsata in Cerrado. The diversity and evenness of species were higher in gallery forest than in the cerrado. The peak of the nests was founded in November (2012 and 2013) and August (2013), there were nothing correlation between the precipitation (rCE = -0.061; pCE = 0.775 and rMG = 0.194; pMG = 0.365). After 24 months of collecting the species rarefaction curve did not reach the asymptote for both habitats. Centris dichrootricha observed nesting in 29 nests in sizes 8, 10, 12 and 14mm. The species used in most resources from the Cerrado, which consisted both in the sediment to compose the cells and the pollen material and floral oil. Pollen types Byrsonima the genus of the Malpighiaceae family were the most representative in the samples. In this study five species of Centris were collected for a single study, all represented in the gallery forest. Thus, the study reveals the importance of forests as a refuge for some species of solitary bees. The biology of C. dichrootricha showed a preference for nesting in cavities with different sizes and in shady places in the Gallery Forest , also Euglossa amazonica species which hitherto had not been recorded nesting in trap-nests, especially in areas of the field was observed Cerrado. Besides these two species, the present study contributes to the expansion of the geographical distribution and Centris bicornuta e Centris terminata, these species are little studied in Brazil. / Conhecer a diversidade de abelhas solitárias através de ninhos-armadilha tem buscado compor um checklist da diversidade, assim como o relato do comportamento e da biologia das espécies. Poucos foram os estudos já realizados no Estado do Maranhão, que é uma zona privilegiada, pois incluem em seus limites os dois principais biomas brasileiros. Diante desses poucos relatos, o propósito desse trabalho foi estudar a comunidade de abelhas solitárias através do método de ninhos-armadilha durante dois anos, em uma área de Cerrado e Mata de Galeria, no Parque Estadual do Mirador. Além disso, descrever a biologia de nidificação de Centris (Hemisiella) dichrootricha e analisar a composição florística do alimento de sua prole. A área de estudo está localizada no Parque Estadual do Mirador, município de Formosa da Serra Negra, Maranhão. O método empregado foi o de ninhos-armadilha de madeira nos diâmetros 6, 8, 10, 12, 14 e 16 mm, estes foram agrupados em conjuntos de 6 ninhos, totalizando 300 ninhos por área. Foi fundado um total de 101 ninhos pertencentes a 11 espécies de abelhas, das quais oito espécies ocorreram na Mata de Galeria e seis no Cerrado, sendo que a similaridade foi baixa entre os habitats (SJ = 0,27). Duas espécies foram dominantes na comunidade, Centris dichrootricha na Mata de Galeria e Centris tarsata no Cerrado. A diversidade e equitabilidade das espécies foram maiores na Mata de Galeria do que no Cerrado. O pico de fundação dos ninhos foi em novembro (2012 e 2013) e agosto (2013), não havendo correlação com a precipitação mensal (rCE = -0,061; pCE = 0,775 e rMG = 0,194; pMG = 0,365). Após 24 meses de coleta a curva de rarefação das espécies não atingiu a assíntota para ambos os habitats. Centris dichrootricha nidificou em 29 ninhos nos diâmetros 8, 10, 12 e 14mm. A espécie utilizou em maioria recursos provenientes do Cerrado, que consistia tanto no sedimento para compor as células quanto o material polínico e óleo floral. Tipos polínicos do gênero Byrsonima da família Malpighiaceae foram os mais representativos nas amostras. Nesse trabalho foram coletadas cinco espécies de Centris para um único estudo, sendo todas representadas na Mata de Galeria. Assim, o estudo revela a importância das áreas florestais como refúgio para algumas espécies de abelhas solitárias. A biologia da C. dichrootricha mostrou uma preferência por nidificar em cavidades com diâmetros variados e em locais sombreados da Mata de Galeria, também foi observada a espécie Euglossa amazonica que até então não havia sido registrada nidificando em ninhos-armadilha, principalmente em áreas de domínio do Cerrado. Além dessas duas espécies, o presente estudo contribui com a ampliação da distribuição geográfica de Centris bicornuta e Centris terminata, espécies estas que são pouco estudadas no Brasil.

The Jiroft valley, in southeastern Iran, was an important agricultural centre since the Early Bronze Age (3rd millennium BCE). The valley is characterized by harsh environmental settings: hot climate with poor rainfall. However, more optimal conditions may have prevailed earlier that supported ancient settlements. A 250-cm sediment core was retrieved from a peat-land at Konar Sandal, a major archaeological find attributed to Jiroft culture. The palynological data from this core was combined with geochemical and sedimentological proxies aimed at establishing the human-environment interactions in the area. The study focus was directed at vegetation history and landscape evolution, hydroclimatic changes and past human activities, that started just after the projected collapse of the Jiroft (4 ka) and extended all the way from the late Bronze Age to the Mongol invasion (0.6 ka). The results indicate that the valley was dominated by Saharo-Sindian open pseudo-savannah vegetation for the last 4000 years. However, due to anthropogenic clearance and intensified agro-pastoral activities, and also climatic factors, the land cover shifted from open xeric scrubland forests to more open, degraded landscapes. The principal human practice in these early settlements was cereal cultivation. But it is likely that during the more arid periods, communities retreated and abandoned agriculture, facilitating successional processes. Such droughts occurred in 4-3.8 ka and 3.4-2.8 ka and were supported by palynological data, C/N and Fe2O3 content. Peat formation was characteristic to the wetland during these arid periods. These droughts corresponded to drought phases detected in other studies, and were attributed to changes in Siberian Anticyclones. Dynamics of Artemisia and desert shrubs indicate milder climate around 3.8-3.4 ka and 2.8-0.6 ka. In the latter episode, during the rule of Persian Empire (ca. 550 BCE-650 CE) and Islamic epoch, the highest vegetation degradation state and most intensive human activities were observed. Some inconspicuous human practices, such as date cultivation, may have occurred on site as an adaptation to extreme environmental conditions. / High-resolution paleolimnological records from Lake Jazmurian: Climate-culture evolution at Jiroft in southeast Iran during the Holocene

L'étude des interglaciaires passés qui sont des périodes chaudes avec un volume de glace réduit comme l’interglaciaire actuel, l'Holocène, est cruciale pour comprendre le climat futur. Ce travail apporte de nouvelles informations sur le climat des interglaciaires clés, les stades isotopiques marins (MIS) 11 et 31, considérés comme des analogues au réchauffement global projeté. Une analyse pollinique des sédiments du Site IODP U1385 (marge sud-ouest ibérique) a été effectuée à haute résolution, ce qui permet de comparer directement les variations de la végétation (atmosphère) avec celles de la température des eaux de surface océaniques. Nos données montrent qu’à l’échelle orbitale, la forêt du sud-ouest de l’Europe pendant le MIS 11 est principalement influencée par la précession alors que pendant le MIS 31, malgré des valeurs de précession extrêmes, le forçage dominant est l’obliquité, favorisant une végétation moins méditerranéenne et un régime climatique tempéré. De plus, la variabilité millénaire apparaît comme une caractéristique persistante mais les épisodes de refroidissement varient en intensité et durée en fonction des conditions limites qui favorisent un forçage prédominant des hautes ou basses latitudes. Enfin, nous examinons l'expression régionale de l'Holocène et de ses analogues orbitaux, les MIS 11c et 19c dans le sud-ouest de l’Europe. Ceci révèle que l'optimum Holocène se distingue par un plus fort développement forestier et donc que les MIS 11c et 19cne sont pas des analogues à l’Holocène pour notre zone d’étude. Grâce à une comparaison modèle-données, nous montrons aussi que la forêt interglaciaire dans cette région est principalement contrôlée par la précession en influençant les précipitations hivernales, facteur critique pour le développement de la forêt méditerranéenne, tandis que le CO2 joue un rôle négligeable. / The study of past interglacials, periods of reduced ice volume like our present interglacial, the Holocene, is crucial for understanding the future climate. This work provides new insights into the intensity and climate variability of key interglacials, namely Marine Isotopic Stages (MIS) 11 and 31, considered as analogues for the projected global warming. A highresolution pollen analysis at IODP Site U1385 off SW Iberia was performed, which enables adirect comparison between atmospheric-driven vegetation changes and sea surface temperature variability. At orbital time scale, this thesis shows that the dominant orbital forcing on the SW European forest was different between the interglacials of the 100-ky (MIS 11) and 41-ky (MIS31) worlds. While during MIS 11 its weak precessional forcing predominates, during MIS 31 itsextreme precession forcing is dwarfed by the prevailing influence of obliquity leading to a temperate climate regime as shown by a less Mediterranean character of the vegetation. This work also shows that millennial-scale variability was a pervasive feature and suggests that the different intensity and duration of the cooling events in SW Iberia was related to different atmospheric and oceanic configurations modulated by high or low-latitude forcing depending on the baseline climate states. Finally, this study examines the dominant forcing underlying the regional expression of the Holocene and its orbital analogues, MIS 11c and 19c, over SW Iberia using a data-model comparison approach. This comparison reveals that the Holocene optimum stands out for its higher forest development and therefore these interglacials cannot be considered as analogues for the Holocene vegetation and climate changes in Iberia. Additionally,it shows that the SW Iberian forest dynamics during these interglacials were primarily controlled by precession through its influence on winter precipitation, which is critical for the Mediterranean forest development whereas CO2 played a negligible role.

Cette thèse a pour objectif d’identifier les trajectoires plurimillénaires des écosystèmes de Corse à basse et moyenne altitude sous la triple influence des forçages climatiques, eustatiques et anthropiques à travers l’étude des assemblages d’insectes fossiles et des données paléobotaniques disponibles ou nouvellement acquises. Cette approche multidisciplinaire a été appliquée sur trois séquences sédimentaires prélevées à l’étang du Greco sur l’île Cavallo, au marais de Cannuta et à la tourbière de Bagliettu.Les résultats obtenus révèlent des changements majeurs dans la structuration du couvert végétal. Des signes d’ouverture du paysage apparaissent sur Cavallo et à Cannuta dès 5500-5000 cal. BP. Ils coïncident avec des indices d’activités des sociétés insulaires, lesquelles s’intensifient après 3000 cal. BP et plus particulièrement depuis 1000 ans à Bagliettu. Notre étude suggère que la sensibilité et la réponse des zones humides littorales face à la remontée relative du niveau marin dépend du contexte géomorphologique. Sur l’île Cavallo où le relief est faible, la transgression marine induit une augmentation de la salinité dans l’étang du Greco vers 3700 cal. BP, qui provoque une chute irréversible de la diversité des coléoptères aquatiques et hygrophiles. Au marais de Cannuta, où l’érosion des versants a favorisé la progradation de la plaine alluviale, notre étude montre une diminution de l’influence marine après 5000 cal. BP et une diversification de cette même entomofaune à partir de 1200 cal. BP. À Bagliettu, nous avons démontré l’importance des changements hydro-morphologiques des rivières dans la dynamique des écosystèmes tourbeux attenants et de leur entomofaune. / This thesis aims to define the multi-millennial trajectories of Corsican ecosystems under the climatic, eustatic and anthropic factors via the study of fossil insect assemblages and previous or new palaeobotanical data. This multidisciplinary approach was carried out at low and middle elevation on three sedimentary archives from the Greco pond on Cavallo Island, the Cannuta marsh and the Bagliettu peat-bog. The results reveal major changes in the structure of the vegetation cover over the last 7000 years. Signs of more open landscapes occurred on Cavallo and in Cannuta from 5500-5000 cal. BP. They coincide with bio-markers of insular societies activities, which increased from 3000 cal. BP onward and more particularly during the last 1000 years at Bagliettu.This study also suggests that the sensitivity and the response of coastal wetlands to the relative sea-level rise depend on the geomorphological context. On the low-lying Cavallo Island, marine transgression induced an increase of salt conditions in the Greco pond from 3700 cal. BP, which in turn, caused an irreversible loss of aquatic and hygrophilous beetle diversity. In Cannuta marsh, erosion on catchment slopes favoured the progradation of the coastal floodplain and the results reveal a progressive decrease of the marine influence from 5000 cal. BP as well as a diversification of this entomofauna over the last 1200 years. In Bagliettu, the results show how hydro-morphological changes of the rivers impact the dynamics of adjacent peaty ecosystems and beetle diversity.