The effect of habitat fragmentation on the structure of orchid bee communities was analyzed by the investigation of the existence of a spatial structure in the richness and abundance of Euglossini species and by determining the relationship between these data and environmental factors. The surveys were carried out in four different forest fragments and one university campus. Richness, abundance, and diversity of species were analyzed in relation to abiotic (size of the area, extent of the perimeter, perimeter/area ratio, and shape index) and biotic characteristics (vegetation index of the fragment and of the matrix of each of the locations studied). We observed a highly significant positive correlation between the diversity index and the vegetation index of the fragment, landscape and shape index. Our analysis demonstrated that the observed variation could be explained mainly by the vegetation index and the size of the fragment. Variations in relative abundance showed a tendency toward an aggregated spatial distribution between the fragments studied, as well as between the sampling stations within the same habitat, demonstrating the existence of a spatial structure on a small scale in the populations of Euglossini. This distribution will determine the composition of species that coexist in the area after fragmentation. These data help in understanding the differences and similarities in the structure of communities of Euglossini resulting from forest fragmentation.
SUMMARYThe results of ecological restoration techniques can be monitored through biological indicators of soil quality such as the leaf litter arthropod fauna. This study aimed to determine the immediate effect of brushwood transposition transferred from an area of native vegetation to a disturbed area, on the leaf litter arthropod fauna in a degraded cerrado area. The arthropod fauna of four areas was compared: a degraded area with signal grass, two experimental brushwood transposition areas, with and without castor oil plants, and an area of native cerrado. In total, 7,660 individuals belonging to 23 taxa were sampled. Acari and Collembola were the most abundant taxa in all studied areas, followed by Coleoptera, Diptera, Hemiptera, Hymenoptera, and Symphyla. The brushwood transposition area without castor oil plants had the lowest abundance and dominance and the highest diversity of all areas, providing evidence of changes in the soil community. Conversely, the results showed that the presence of castor oil plants hampered early succession, negatively affecting ecological restoration in this area.Index terms: ecological restoration, signal grass, mesofauna, Acari, Collembola.(1) Extracted from the first author's Scientific Initiation submitted to the Department of Biological Sciences, UNESP -Univ Estadual Paulista, Campus
Recebido em 9/6/05; aceito em 2/12/05; publicado na web em 14/6/06 MULTIRESIDUE METHOD FOR MONITORING ENVIRONMENTAL CONTAMINATION BY PESTICIDES IN THE BAURU REGION (SP) USING HONEY AS BIOINDICATOR.The presence of residues of the major groups of pesticides (organohalogen, organophosphorous, pyrethroids and organonitrogen) in representative samples of honey produced in Bauru (state of São Paulo, Brazil) was investigated from 1999 through2004. A multiresidue method was applied to honey samples to determine 48 pesticides with recoveries ranging from 76 to 95%. The limits of detection found were lower than 10 μg/kg for GC-MS-SIM. The results indicated that most pesticides found in the samples belonged to the organohalogen and organonitrogen groups. Residues of malathion were detected in almost all of the samples in high concentration.Keywords: multiresidue pesticide; honey; environmental contamination. INTRODUÇÃONo Brasil, segundo dados da APACAME (Associação Paulista de Apicultores, Criadores de Abelhas Melíficas Européias) as estatísticas sobre a cadeia apícola revelam que, em 2003, existiam 80.000 apicultores, dos quais 85% eram considerados pequenos (10 a 20 colméias) e praticavam a apicultura fixa e os 15% restantes eram considerados apicultores profissionais (média de 400 colméias) e praticavam a apicultura migratória. As 1.600.000 colméi-as habitadas pelas abelhas africanizadas produziam 35.000 t de mel/ano; no entanto, o potencial de produção é estimado em 200.000 t de mel/ano. Atualmente, as exportações brasileiras de mel triplicaram e o mercado atual dos produtos apícolas no país é de US$ 360 milhões, valor muito aquém do potencial, avaliado em US$ 1 bilhão 1,2 . As abelhas domésticas (Apis mellifera) executam a tarefa vital de polinização das colheitas agrícolas e das espécies nativas, e são importantes para a produção comercial do mel e de produtos apícolas. A cada dia, de 10.000 a 25.000 abelhas operárias fazem uma média de 10 viagens para explorar aproximadamente 7 km 2 nas áreas que cercam seu habitat, recolhendo o néctar, a água e o pólen das flores. Durante este processo, diversos microorganismos, produtos químicos e partículas suspensas no ar são interceptados por estas trabalhadoras e ficam retidos nos pelos superficiais de seu corpo ou são inalados e unidos em seu aparelho respiratório. Devido a estes fatores, as abelhas podem ser usadas como bioindicadores para monitoramento de impacto ambiental causado por fatores biológicos, químicos e físicos, tais como parasitas, contaminações industriais ou pesticidas 3,4 . Além disso, quase todos os setores ambientais (solo, vegetação, água, ar) são explorados pelas abelhas produtoras de mel, fornecendo numerosos indicadores para cada estação 3 (Figura 1).A produção de mel oriundo de floradas silvestres está se tornando cada vez mais escassa no Brasil e no mundo. Por esse motivo, atualmente o desenvolvimento da apicultura está cada vez mais dependente das culturas agrícolas e florestais nas quais, em alguns casos, são utilizados pesticidas de maneira inadeq...
ABSTRACT. The foraging activity of Geotrigona mombuca Smith, 1863 was studied under natural conditions aiming to verify the influence of seasonal changes on daily flight activity and annual cycle of the colony. Daily flight activity was monitored for a year based on the observation and counting of foragers leaving and entering the hive, as well as the kind of material transported and meteorological factors such as day time, temperature and relative humidity. The influence of seasonal changes was evidenced by alterations on daily rhythm of flight activity and by differences on transportation of food resources, building material and garbage. These data indicate that forager behavior is related to daily microclimate conditions and it is synchronized with the requirements of colony annual cycle, which determines an intense pollen collection in the summer. Thus, the recomposition of the intranidal population in spring and summer can be ensured, which is characterized both for a higher intensity of flight activity and increase in garbage and resin transport, as well as the swarming process in the spring. In this way, an action targeting the preservation or management of the species in a natural environment should consider that survival and reproduction of the colony depends greatly on the amount of available pollen in late winter. KEYWORDS.Meteorological factors, daily activity, seasonality, floral resources.RESUMO. Influência das mudanças sazonais na atividade diária e no ciclo de vida anual de Geotrigona mombuca (Hymenoptera, Apidae) em hábitat de cerrado, São Paulo, Brasil. A atividade de forrageamento de Geotrigona mombuca Smith, 1863 foi estudada em condições naturais com o objetivo de verificar a influência das mudanças sazonais na atividade diária e no ciclo anual da colônia. A atividade diária de voo foi monitorada, durante um ano, através de contagens de campeiras observadas saindo e entrando na colmeia e o tipo de material transportado, juntamente com os fatores meteorológicos hora do dia, temperatura e umidade relativa do ar. A influência das mudanças sazonais foi constatada pela alteração do ritmo diário da atividade de voo e pelas diferenças no transporte de recursos alimentares, material de construção e de resíduos. Esses dados evidenciam que o comportamento das campeiras está relacionado às condições microclimáticas diárias e sincronizadas com as exigências do ciclo anual da colônia, o qual determina uma intensa coleta de pólen no verão, garantindo a recomposição da população intranidal na primavera e verão, caracterizada tanto pela maior intensidade de atividadede de voo como pelo aumento do transporte de resina e lixo, e enxameagem na primavera. Desse modo, ações direcionadas para a preservação da espécie em ambiente natural ou para o manejo devem considerar que a sobrevivência e reprodução da colônia depende muito da quantidade de pólen disponível no final do inverno.PAlAvRAS-CHAvE. Fatores meteorológicos, atividade diária, sazonalidade, recursos florais.
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