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A Survey of Invasive Exotic Ants Found on Hawaiian Islands: Spatial Distributions and Patterns of AssociationMartin, Camie Frandsen 07 December 2012 (has links) (PDF)
An intensive sampling of all ant species encountered on 6 Hawaiian Islands: Big Island, Maui, Oahu, Kauai, Molokai, and Lanai took place between 1988 and 1996. Species presence and absence was recorded at each site. Using remote sensing, variables were added insitu and used throughout my analysis. Species accumulation curves suggest that sampling was comprehensive. There is a significant trend between island area and species richness which validates the Theory of Island Biogeography for invasive species. Islands were found to be significantly nested by area, order, and tourism. Cluster analysis shows a link between elevation, land-use and island, and species presence. Predictive models can be built to predict spread of particular ant species as they continue toward equilibrium.
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Estrutura de comunidades de formigas (Hymenoptera: Formicidae) do planalto do Itatiaia, Rio de Janeiro, BrasilMartins, Luciano 25 February 2011 (has links)
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Previous issue date: 2011-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study aims to compare three sampling techniques to estimate species richness of ants
(Hymenoptera: Formicidae) in ?campos of altitude? at Itatiaia National Park, in Rio de Janeiro
state. Compared richness estimates for genera and species, and curves of accumulation of species
for sardine baits, pitfall traps and manual collecting are presented for two distinct sites ("steppe
vegetation" [VE] and "rupicola vegetation" [VR]) in Itatiaia Plateau. The three techniques
collected 31 species of 10 genera belonging to four subfamilies. In VE were registered 50% of
genera and 36.4% of species collected exclusively by baits, and 20% and 50% by pitfall traps,
respectively. In VR were registered 37.5% of genera and 47.61% of species exclusive for baits,
but no one genus and species was restricted for manual collecting. In the case of ?campos de
altitude? and when only one technique can be used, the sardine bait was the most efficient sample
technique to registered richness at VE. For VR, the manual collecting was the most appropriate
technique to record species richness. However, the pitfalls (in VE) and bait (in VR) recorded an
important portion of species richness. In our data, the manual collecting were associated with
standardized data collecting protocols, and, although much criticized, have shown effectiveness
in recording species in habitats where widespread techniques cannot be used. In spite of different
physiognomies show differentiated efficiency for samples techniques, it is relevant to using more
than one technique associated to a colleting protocol well structured to potentiated the record of
the new species in environments as the ?campos de altitude?. / O presente trabalho tem por objetivo comparar tr?s t?cnicas de coleta para estimar a riqueza de
esp?cies de formigas (Hymenoptera: Formicidae) no Planalto do Itatiaia , Rio de Janeiro, Brasil.
S?o apresentados dados comparativos das estimativas da riqueza de g?neros, de esp?cies e as
curvas de acumula??o de esp?cies amostradas com iscas de sardinha, armadilhas de queda e
coletas manuais, em duas fisionomias distintas (?vegeta??o est?pica? [VE] e ?vegeta??o
rup?cola? [VR]), no Planalto do Itatiaia. Com a utiliza??o das tr?s t?cnicas foram coletadas 30
esp?cies de 11 g?neros, pertencentes a quatro subfam?lias. Para a VE foram registrados 50% dos
g?neros e 36,4% das esp?cies coletadas exclusivamente pelas iscas, e 20% e 50% pela armadilha
de queda, respectivamente. Para a VR foram registrados 37,5% e 47,61% dos g?neros e esp?cies
exclusivas para iscas, por?m nenhum g?nero e esp?cie foram restritos a coleta manual. Em se
tratando de ecossistema de campos de altitude e quando apenas uma das t?cnicas possa ser
utilizada, a isca de sardinha foi a mais eficiente para amostrar a riqueza em VE. Para VR, a coleta
manual se apresentou como a t?cnica mais apropriada para registrar sua riqueza. No entanto, as
armadilhas de queda (na VE) e as iscas (na VR) registraram uma parcela n?o t?o desprez?vel da
riqueza. Em nossos dados, as coletas manuais foram associadas a protocolos de coleta
padronizados, e, apesar de serem bastante criticadas, mostraram efici?ncia no registro de esp?cies
em habitats em que outras t?cnicas mais difundidas n?o podem ser utilizadas. Apesar de
fisionomias distintas apresentarem efici?ncia de t?cnica de coleta diferenciada, ? relevante a
utiliza??o das tr?s t?cnicas para se potencializar ainda mais o registro das esp?cies em ambientes
de campos de altitude.
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Etude multi-échelle du patron de diversité des abeilles et utilisation des ressources fleuries dans un agrosystème intensif / Multi-scale study of bee diversity pattern and floral resource use in intensive agricultural landscapeRollin, Orianne 11 December 2013 (has links)
Les abeilles sont des pollinisateurs essentiels pour les cultures et les plantes sauvages, mais l'intensification des pratiques agricoles a engendré une baisse importante de leur abondance et diversité. Afin de protéger efficacement les abeilles dans les paysages agricoles, il est nécessaire d'avoir une meilleure connaissance de leurs patrons de diversité. L'objectif général de cette thèse était de déterminer les patrons spatio-temporels de la diversité des abeilles et l'utilisation des ressource fleuries dans un système agricole intensif. L'échantillonnage spatialement extensif de l'activité de butinage des abeilles sauvages et domestiques nous a permis de recenser 45040 individus (29314 abeilles domestiques et 15726 sauvages), appartenant à 192 espèces recensées à l'échelle territoriale. Cette diversité représente près de 20% de la richesse des espèces apiformes connues à l'échelle nationale. Cette communauté est caractérisée par une forte proportion d'espèces rares (28,8%) et de fortes variations temporelles et spatiales, en particulier de l'échelle locale jusqu'à 10-20 km2. L'importance des habitats semi-naturels pour soutenir les populations d'abeilles sauvages a été confirmée dans cette étude. Durant les périodes de floraison des cultures oléagineuses, les abeilles sauvages étaient étroitement associées aux habitats semi-naturels alors que les abeilles domestiques ont montré une nette préférence pour les cultures à floraison massive. La diversité des abeilles sauvages dans les habitats semi- naturels était 3-4 fois supérieure à celle observée dans le colza ou le tournesol. L'importance de certains facteurs écologiques clefs pour la diversité des abeilles, comme la richesse floristique locale et la quantité d'habitats semi-naturels dans le paysage, a été confirmée et quantifiée. Il a également été démontré que ces effets varient en fonction de la saison et de l'échelle spatiale. Ces résultats mettent en évidence les processus écologiques responsables des partons de diversité des abeilles à différentes échelles spatiales, et peuvent contribuer à optimiser la conception des mesures de conservation visant à promouvoir la diversité des abeilles dans les agrosystèmes intensifs. / Bees are essential pollinators for crops and wild plants, but theintensification of agricultural practices have contributed to a significantdecline in their abundance and diversity. To effectively protect andpromote the bee fauna in agroecosystems, a better knowledge of theirdiversity patterns is required. The over-arching objective of this thesiswas to determine the spatial and temporal patterns of bee diversity andfloral resource use in an intensive agricultural system in western France.A spatially extensive survey of foraging wild bees and honey bees returned45.040 individual records at the territorial scale (29.314 honey bees and15.726 wild bees), representing 192 species, i.e. nearly 20% of the speciesrichness reported at the national scale. The bee community wascharacterised by a large proportion of uncommon species (28.8 %) and bysignificant temporal and spatial variations of the diversity, especially atlocal scales up to 10-20 km2. The importance of semi-natural habitats forsustaining wild bee populations was highlighted in this study. Duringoleaginous crop flowering periods, wild bees were tightly associated withsemi-natural habitats while honey bees have shown a clear preference formass-flowering crops. The diversity of foraging wild bees was 3-4 timesgreater in semi-natural habitats than in oilseed rape or sunflower fields.The importance of some keystone ecological correlates of bee diversity,such as the local floral richness and the amount of semi-natural habitatsin the vicinity, has been confirmed and quantified. It was also evidencedthat their effect varies among seasons and spatial scales. These resultshighlight the ecological processes underlying bee diversity patterns atdifferent spatial scales, and further help to optimise the efficiency ofconservation measures intended to promote bee diversity in intensiveagrosystems.
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Zentrale und periphere Populationen von Hornungia petraea: Biodiversität und Demographie auf unterschiedlichen raum-zeitlichen Skalenebenen / Central and peripheral populations of Hornungia petraea: biodiversity and demography on different spatio-temporal scalesKluth, Christian 27 April 2004 (has links)
No description available.
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Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yieldMaas, Bea 20 November 2013 (has links)
No description available.
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