997 resultados para PLANT MATTER


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On the nesting biology of Pirhosigma Giordani Soika (Hymenoptera, Vespidae, Eumeninae), with special reference to the use of vegetable matter. The use of vegetable matter in nest building is not widespread among the Eumeninae, and is reported for the first time for the two species of potter wasps Pirhosigma superficiale and P. limpidum. These wasps make mostly spherical mud nests over which they attach small pieces of unmasticated plant matter. Use of plant fragments in this group of wasps is interpreted as camouflage behavior.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Das Ziel dieser Arbeit war, die Einflüsse von Wurzeln und Rhizodeposition auf den Umsatz von Körnerleguminosenresiduen und damit verknüpfte mikrobielle Prozesse zu untersuchen. In einem integrierten Versuch wurden Ackerbohne (Vicia faba L.), Erbse (Pisum sativum L.) und Weiße Lupine (Lupinus albus L.) untersucht. Der Versuch bestand aus drei Teilen, zwei Gefäß-Experimenten und einem Inkubationsexperiment, in denen ausgehend von einem Gefäß-Experiment derselbe Boden und dasselbe Pflanzenmaterial verwendet wurden. In Experiment I wurde die Stickstoff-Rhizodeposition der Körnerleguminosenarten, definiert als wurzelbürtiger N nach dem Entfernen aller sichtbaren Wurzeln im Boden, gemessen und der Verbleib des Rhizodepositions-N in verschiednenen Bodenpools untersucht. Dazu wurden die Leguminosen in einem Gefäßversuch unter Verwendung einer in situ 15N-Docht-Methode mit einer 15N Harnstofflösung pulsmarkiert. In Experiment II wurde der Umsatz der N-Rhizodeposition der Körnerleguminosen und der Einfluss der Rhizodeposition auf den anschließenden C- und N-Umsatz der Körnerleguminosenresiduen in einem Inkubationsexperiment untersucht. In Experiment III wurde der N-Transfer aus den Körnerleguminosenresiduen einschließlich N-Rhizodeposition in die mikrobielle Biomasse und die Folgefrüchte Weizen (Triticum aestivum L.) und Raps (Brassica napus L.) in einem Gewächshaus-Gefäßversuch ermittelt. Die in situ 15N Docht-Markierungs-Methode wies hohe 15N Wiederfindungsraten von ungefähr 84 Prozent für alle drei Leguminosenarten auf und zeigte eine vergleichsweise homogene 15N Verteilung zwischen verschiedenen Pflanzenteilen zur Reife. Die Wurzeln zeigten deutliche Effekte auf die N-Dynamik nach dem Anbau von Körnerleguminosen. Die Effekte konnten auf die N-Rhizodeposition und deren anschließenden Umsatz, Einflüsse der Rhizodeposition von Körnerleguminosen auf den anschließenden Umsatz ihrer Residuen (Stängel, Blätter, erfassbare Wurzeln) und die Wirkungen nachfolgender Nichtleguminosen auf den Umsatzprozess der Residuen zurückgeführt werden: Die N-Rhizodeposition betrug zur Reife der Pflanzen bezogen auf die Gesamt-N- Aufnahme 13 Prozent bei Ackerbohne und Erbse und 16 Prozent bei Weißer Lupine. Bezogen auf den Residual N nach Ernte der Körner erhöhte sich der relative Anteil auf 35 - 44 Prozent. Die N-Rhizodeposition ist daher ein wesentlicher Pool für die N-Bilanz von Körnerleguminosen und trägt wesentlich zur Erklärung positiver Fruchtfolgeeffekte nach Körnerleguminosen bei. 7 - 21 Prozent des Rhizodepositions-N wurden als Feinwurzeln nach Nasssiebung (200 µm) wiedergefunden. Nur 14 - 18 Prozent des Rhizodepositions-N wurde in der mikrobiellen Biomasse und ein sehr kleiner Anteil von 3 - 7 Prozent in der mineralischen N Fraktion gefunden. 48 bis 72 Prozent der N-Rhizodeposition konnte in keinem der untersuchten Pools nachgewiesen werden. Dieser Teil dürfte als mikrobielle Residualmasse immobilisiert worden sein. Nach 168 Tagen Inkubation wurden 21 bis 27 Prozent des Rhizodepositions-N in den mineralisiert. Der mineralisierte N stammte im wesentlichen aus zwei Pools: Zwischen 30 Prozent und 55 Prozent wurde aus der mikrobiellen Residualmasse mineralisiert und eine kleinere Menge stammte aus der mikrobielle Biomasse. Der Einfluss der Rhizodeposition auf den Umsatz der Residuen war indifferent. Durch Rhizodeposition wurde die C Mineralisierung der Leguminosenresiduen nur in der Lupinenvariante erhöht, wobei der mikrobielle N und die Bildung von mikrobieller Residualmasse aus den Leguminosenresiduen in allen Varianten durch Rhizodepositionseinflüsse erhöht waren. Das Potential des residualen Körnerleguminosen-N für die N Ernährung von Folgefrüchten war gering. Nur 8 - 12 Prozent des residualen N wurden in den Folgenfrüchten Weizen und Raps wiedergefunden. Durch die Berücksichtigung des Rhizodepositions-N war der relative Anteil des Residual-N bezogen auf die Gesamt-N-Aufnahme der Folgefrucht hoch und betrug zwischen 18 und 46 Prozent. Dies lässt auf einen höheren N-Beitrag der Körnerleguminosen schließen als bisher angenommen wurde. Die residuale N-Aufnahme von Weizen von der Blüte bis zur Reife wurde durch den Residual-N gespeist, der zur Blüte in der mikrobiellen Biomasse immobilisiert worden war. Die gesamte Poolgröße, Residual-N in der mikrobiellen Biomasse und in Weizen, veränderte sich von der Blüte bis zur Reife nicht. Jedoch konnte ein Rest von 80 Prozent des Residual-N in keinem der untersuchten Pools nachgewiesen werden und dürfte als mikrobielle Residualmasse immobilisiert worden sein oder ist noch nicht abgebaut worden. Die zwei unterschiedlichen Folgefrüchte - Weizen und Raps - zeigten sehr ähnliche Muster bei der N-Aufnahme, der Residual-N Wiederfindung und bei mikrobiellen Parametern für die Residuen der drei Körnerleguminosenarten. Ein differenzierender Effekt auf den Umsatz der Residuen bzw. auf das Residual-N-Aneignungsvermögen der Folgefrüchte konnte nicht beobachtet werden.

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Hedgehog proteins are important cell-cell signalling proteins utilized during the development of multicellular animals. Members of the hedgehog gene family have not been detected outside the Metazoa, raising unanswered questions about their evolutionary origin. Here we report a highly unusual hedgehog-related gene from a choanoflagellate, a close unicellular relative of the animals. The deduced C-terminal domain, Hoglet-C, is homologous to the autocatalytic domain of Hedgehog proteins and is predicted to function in autocatalytic cleavage of the precursor peptide. In contrast, the N-terminal Hoglet-N peptide has no similarity to the signalling peptide of Hedgehog (Hh-N). Instead, Hoglet-N is deduced to be a secreted protein with an enormous threonine-rich domain of unprecedented size and purity (over 200 threonine residues) and two polysaccharide-binding domains. Structural modelling reveals that these domains have a novel combination of features found in cellulose-binding domains (CBD) of types IIa and IIb, and are expected to bind cellulose. We propose that the two CBD domains enable Hoglet-N to bind to plant matter, tethering an amorphous nucleophilic anchor, facilitating transient adhesion of the choanoflagellate cell. Since HhC and Hoglet-C are homologous, but Hh-N and Hoglet-N are not, we argue that metazoan hedgehog genes evolved by fusion of two distinct genes.

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Here we describe the stomach contents of nine small mammal species (seven rodents and two didelphid marsupials) co-occurring in an old-growth Atlantic forest area. For four terrestrial rodents, we also compared the importance of arthropods in the diet and the selection of arthropod groups by comparing consumption with availability. Small mammals and arthropods were sampled in a 36-ha grid containing 25 sampling stations spaced every 150 m, and 47 stomach contents were analysed. While plant matter was the predominant item in the stomach contents of two rodents (Oligoryzomys nigripes and Rhipidomys mastacalis), four species presented arthropods as the main food item (the rodents Brucepattersonius soricinus and Oxymycterus dasytrichus, and the marsupials Monodelphis n. sp. and Marmosops incanus) and three consumed more plant matter than arthropods, but had significant amounts of both items (the rodents Delomys sublineatus, Euryoryzomys russatus and Thaptomys nigrita). Our results suggest that differences in diet, coupled with differences in habit and microhabitat preferences, are important factors allowing resource partition among species of the diverse group of co-occurring terrestrial small mammals in Atlantic forest areas. Moreover, arthropods were not preyed opportunistically by any of the four terrestrial rodents, since consumption was not proportional to availability. Rather, selection or rejection of arthropod groups seems to be determined by aspects other than availability, such as nutritional value, easiness of capture and handling or palatability.

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O objetivo deste trabalho foi avaliar sistemas de consorciação entre milho e Brachiaria decumbens e seus efeitos sobre a nutrição mineral das culturas. O experimento foi conduzido no ano agrícola de 2005, na Área Experimental do Campus Delza Gitaí, pertencente ao CECA-UFAL. Os tratamentos consistiram do cultivo de um híbrido de milho BRS 3150, nos sistemas: Preparo Convencional do Solo, Cultivo Mínimo e Semeadura Direta (BRS 3150 em consórcio com Brachiaria decumbens). O experimento obedeceu ao esquema de blocos casualisados com parcelas subdivididas em quatro repetições. Durante o período de florescimento da cultura do milho, foram coletadas folhas da base da espiga para análise nutricional. Foram realizadas coletas de material vegetal da Brachiaria decumbens em quatro épocas para determinação de massa seca; para análise nutricional, utilizou-se material vegetal proveniente da terceira coleta. Pôde-se observar que a presença da Brachiaria decumbens não interferiu na nutrição mineral da cultura do milho; o efeito residual da adubação realizada para cultura do milho beneficiou a Brachiaria decumbens, elevando seu valor nutritivo; a Brachiaria decumbens teve seu crescimento limitado, quando cultivada em consórcio, devido ao efeito do sombreamento proporcionado pela cultura do milho.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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A análise da alimentação da pirapitinga do sul (Brycon opalinus), peixe ameaçado de extinção de rios da Mata Atlântica da Serra do Mar na região Sudeste, revelou a ocorrência de itens alimentares incomuns. As espécies deste gênero são onívoras oportunistas e alimentam-se de itens vegetais e animais, tais como: flores, folhas, frutos e sementes e grande variedade de insetos. em três rios do Parque Estadual da Serra do Mar - Núcleo Santa Virgínia foram encontrados exemplares de B. opalinus que consumiram três itens animais incomuns, os anfíbios Hypsiboas aff. pardalis (Anura, Hylidae) e Eleutherodactylus guentheri (Anura, Leptodactylidae) e o mamífero Oligoryzomys cf. nigripes (Rodentia, Sigmodontinae). O registro do consumo destas espécies de vertebrados foi relacionado com o período de chuvas, quando o material animal ou vegetal carreado até o rio pode ser consumido por B. opalinus, mesmo que não sejam itens habituais para a espécie. A mata ripária preservada, como foi verificado nos três rios do Parque Estadual da Serra do Mar - Núcleo Santa Virgínia (SP), é de suma importância para o fornecimento de itens alimentares animais e vegetais e pela manutenção das condições bióticas e abióticas para a sobrevivência de B. opalinus.

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Background It is generally accepted that material collected by leaf-cutting ants of the genus Acromyrmex consists solely of plant matter, which is used in the nest as substrate for a symbiotic fungus providing nutrition to the ants. There is only one previous report of any leaf-cutting ant foraging directly on fungal basidiocarps. Findings Basidiocarps of Psilocybe coprophila growing on cow dung were actively collected by workers of Acromyrmex lobicornis in Santa Fé province, Argentina. During this behaviour the ants displayed typical signals of recognition and continuously recruited other foragers to the task. Basidiocarps of different stages of maturity were being transported into the nest by particular groups of workers, while other workers collected plant material. Conclusions The collection of mature basidiocarps with viable spores by leaf-cutting ants in nature adds substance to theories relating to the origin of fungiculture in these highly specialized social insects. © 2013 Masiulionis et al.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Studies on feeding ecology are important tools for the understanding of feeding strategies and niche dynamics. Information on the type of food consumed, how, and where it is acquired, enable the elucidation of species behavioral, evolutionary and ecological aspects. The diet study based on fecal material enables a low-cost, informative research and avoids the sacrifice of animals. The general aim of this study is to characterize the diet of Euphractus sexcinctus, the yellow-armadillo, based on fecal samples, to contribute with additional information on their feeding habits. The study was undertaken at the Nhumirim ranch, Pantanal da Nhecolândia, MS, during the months of February and March, 2014. The fecal material was collected during the manual capture of the animals and oven dried at 60°C. The food items found in the feces were sorted using a magnifying glass and separated in the following categories: plant matter, invertebrates and soil. Invertebrates were identified to the order level and the plant matter to the lowest taxonomic level possible. Aiming to evaluate the invertebrate availability in the soil, pitfall traps were installed next to the location where individuals were captured, during the months of April and May. We were able to estimate the frequency with which item was consumed during the studied period, and if there is a relationship between the frequency of consumed invertebrates and their availability environment. Among the analyzed samples, we could observe the frequency of occurrence (FO) of plant matter, invertebrates and soil in all the samples. The main invertebrate orders found in the samples were: Coleoptera, Orthoptera and Hymenoptera, with FO of 100%, 100% and 87,5%, respectively. Seeds were found in 100% of the samples. The FO of the Byrsonima orbignyana was high (62,5%), and evidences the potential of the yellow-armadillos as seed dispersers. The use of other techniques, such as the micro-histological...

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Studies on feeding ecology are important tools for the understanding of feeding strategies and niche dynamics. Information on the type of food consumed, how, and where it is acquired, enable the elucidation of species behavioral, evolutionary and ecological aspects. The diet study based on fecal material enables a low-cost, informative research and avoids the sacrifice of animals. The general aim of this study is to characterize the diet of Euphractus sexcinctus, the yellow-armadillo, based on fecal samples, to contribute with additional information on their feeding habits. The study was undertaken at the Nhumirim ranch, Pantanal da Nhecolândia, MS, during the months of February and March, 2014. The fecal material was collected during the manual capture of the animals and oven dried at 60°C. The food items found in the feces were sorted using a magnifying glass and separated in the following categories: plant matter, invertebrates and soil. Invertebrates were identified to the order level and the plant matter to the lowest taxonomic level possible. Aiming to evaluate the invertebrate availability in the soil, pitfall traps were installed next to the location where individuals were captured, during the months of April and May. We were able to estimate the frequency with which item was consumed during the studied period, and if there is a relationship between the frequency of consumed invertebrates and their availability environment. Among the analyzed samples, we could observe the frequency of occurrence (FO) of plant matter, invertebrates and soil in all the samples. The main invertebrate orders found in the samples were: Coleoptera, Orthoptera and Hymenoptera, with FO of 100%, 100% and 87,5%, respectively. Seeds were found in 100% of the samples. The FO of the Byrsonima orbignyana was high (62,5%), and evidences the potential of the yellow-armadillos as seed dispersers. The use of other techniques, such as the micro-histological...

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We present the results of airborne measurements of carbon monoxide (CO) and aerosol particle number concentration (CN) made during the Balan double dagger o Atmosf,rico Regional de Carbono na Amazonia (BARCA) program. The primary goal of BARCA is to address the question of basin-scale sources and sinks of CO2 and other atmospheric carbon species, a central issue of the Large-scale Biosphere-Atmosphere (LBA) program. The experiment consisted of two aircraft campaigns during November-December 2008 (BARCA-A) and May-June 2009 (BARCA-B), which covered the altitude range from the surface up to about 4500 m, and spanned most of the Amazon Basin. Based on meteorological analysis and measurements of the tracer, SF6, we found that airmasses over the Amazon Basin during the late dry season (BARCA-A, November 2008) originated predominantly from the Southern Hemisphere, while during the late wet season (BARCA-B, May 2009) low-level airmasses were dominated by northern-hemispheric inflow and mid-tropospheric airmasses were of mixed origin. In BARCA-A we found strong influence of biomass burning emissions on the composition of the atmosphere over much of the Amazon Basin, with CO enhancements up to 300 ppb and CN concentrations approaching 10 000 cm(-3); the highest values were in the southern part of the Basin at altitudes of 1-3 km. The Delta CN/Delta CO ratios were diagnostic for biomass burning emissions, and were lower in aged than in fresh smoke. Fresh emissions indicated CO/CO2 and CN/CO emission ratios in good agreement with previous work, but our results also highlight the need to consider the residual smoldering combustion that takes place after the active flaming phase of deforestation fires. During the late wet season, in contrast, there was little evidence for a significant presence of biomass smoke. Low CN concentrations (300-500 cm(-3)) prevailed basinwide, and CO mixing ratios were enhanced by only similar to 10 ppb above the mixing line between Northern and Southern Hemisphere air. There was no detectable trend in CO with distance from the coast, but there was a small enhancement of CO in the boundary layer suggesting diffuse biogenic sources from photochemical degradation of biogenic volatile organic compounds or direct biological emission. Simulations of CO distributions during BARCA-A using a range of models yielded general agreement in spatial distribution and confirm the important contribution from biomass burning emissions, but the models evidence some systematic quantitative differences compared to observed CO concentrations. These mismatches appear to be related to problems with the accuracy of the global background fields, the role of vertical transport and biomass smoke injection height, the choice of model resolution, and reliability and temporal resolution of the emissions data base.

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Abstract. Organic matter preserved in Lake Ohrid sediments originates from aquatic and terrestrial sources. Its variable composition reflects climate-controlled changes in the lake basin’s hydrology and related organic matter export, i.e. changes in primary productivity, terrestrial plant matter input and soil erosion. Here, we present first results from lipid biomarker investigations of Lake Ohrid sediments from two near-shore settings: site Lz1120 near the southern shore, with low-lying lands nearby and probably influenced by river discharge, and site Co1202 which is close to the steep eastern slopes. Variable proportions of terrestrial n-alkanoic acids and n-alkanols as well as compositional changes of !- hydroxy acids document differences in soil organic matter supply between the sites and during different climate stages (glacial, Holocene, 8.2 ka cooling event). Changes in the vegetation cover are suggested by changes in the dominant chain length of terrestrial n-alkanols. Effective microbial degradation of labile organic matter and in situ contribution of organic matter derived from the microbes themselves are both evident in the sediments. We found evidence for anoxic conditions within the photic zone by detecting epicholestanol and tetrahymanol from sulphur-oxidising phototrophic bacteria and bacterivorous ciliates and for the influence of a settled human community from the occurrence of coprostanol, a biomarker for human and animal faeces (pigs, sheep, goats), in an early Holocene sample. This study illustrates the potential of lipid biomarkers for future environmental reconstructions using one of Europe’s oldest continental climate archives, Lake Ohrid.