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1.
Ecotoxicology ; 32(7): 937-947, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37733275

ABSTRACT

The impact of agrochemicals on native Brazilian bees may be underestimated, since studies of non-target effects on bees have, by and large, concerned mostly the Apis mellifera L. Furthermore, bees may be exposed in the field to multiple agrochemicals through different routes, thus suggesting the necessity for more comprehensive toxicological experiments. Here, we assessed the lethal and sublethal toxicity of multiple agrochemicals (herbicide [glyphosate - Roundup®], fungicide [mancozeb], insecticide [thiamethoxam]) through distinct routes of exposure (contact or ingestion) to an endangered native Brazilian bee Melipona (Michmelia) capixaba Moure & Camargo, 1994 and to A. mellifera. Results indicate that none of the agrochemicals caused feeding repellency on the bees. Thiamethoxam caused high mortality of both species, regardless of the route of exposure or the dose used. In addition, thiametoxam altered the flight capacity of M. capixaba when exposed to the lowest dose via contact exposure. The field dose of glyphosate caused high mortality of both bee species after oral exposure as well as impaired the flight capacity of A. mellifera (ingestion exposure) and M. capixaba (contact exposure). The lower dose of glyphosate also impaired the flight of M. capixaba through either routes of exposure. Exposure of A. mellifera through contact and ingestion to both doses of mancozeb caused high mortality and significantly impaired flight capacity. Taken altogether, the results highlight the importance of testing the impact of multiple agrochemicals (i.e. not just insecticides) through different routes of exposure in order to understand more comprehensively the potential risks for Apis and non-Apis bees.

2.
Integr Environ Assess Manag ; 16(5): 631-635, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32406986

ABSTRACT

The environmental consequences associated with the Fundão tailings dam failure in Mariana, Minas Gerais, Brazil on 5 November 2015 are still being investigated. Bees are the main pollinators believed to be most affected by the accident because they occur throughout the area affected by the dam rupture and build their nests in the soil. In this study, we evaluated the richness of different bee species in areas affected and not affected by the accident and measured the concentration of different metals on the pollen basket, or corbicula, located on the hind legs of Apis mellifera. Diversity indices were similar and there was no statistical difference in the diversity of bees sampled when comparing the sites affected and not affected by the tailings mud, either before or after the dam rupture. It is possible that the similarity is due to nearby forests that may be serving as areas of refuge. The levels of Al, Cu, Cd, Hg, and Pb in A. mellifera suggest no change in the level of metals in pollen collected by the bees that can be attributed to the rupture of the dam. Integr Environ Assess Manag 2020;16:631-635. © 2020 SETAC.


As consequências ambientais da ruptura da barragem de Fundão, ocorrida em Mariana, Minas Gerais, Brasil, em 5 de novembro de 2015, ainda estão sendo investigadas. As abelhas, principal grupo de polinizadores, podem ter sido afetadas direta e indiretamente, uma vez que a maioria das espécies constrói seus ninhos no solo. Neste estudo, avaliamos a riqueza de espécies de abelhas nas áreas afetadas e não afetadas e medimos a concentração de metais pesados nas corbículas de Apis mellifera, espécie que ocorre em toda a área afetada pela ruptura da barragem. Os índices de diversidade foram semelhantes e não houve diferença estatística na diversidade de abelhas amostradas quando comparamos locais afetados e não afetados pela lama de rejeitos após o rompimento da barragem. É possível que a semelhança se deva a florestas próximas que possam estar servindo como áreas de refúgio. Os resultados mostraram a presença de Al, Cu, Cd, Hg e Pb em A. mellifera. Nossos resultados indicam que não há efeito da contaminação de metais pesados nas abelhas devido à ruptura da barragem. Integr Environ Assess Manag 2020;16:631-635.


Subject(s)
Environment , Soil , Structure Collapse , Animals , Bees , Brazil , Metals , Pollen , Pollination , Water Supply
3.
Genet Mol Biol ; 36(1): 111-7, 2013 03.
Article in English | MEDLINE | ID: mdl-23569416

ABSTRACT

Melipona quadrifasciata is a stingless bee widely found throughout the Brazilian territory, with two recognized subspecies, M. quadrifasciata anthidioides, that exhibits interrupted metasomal stripes, and M. quadrifasciata quadrifasciata, with continuous metasomal stripes. This study aimed to estimate the genetic variability of these subspecies. For this purpose, 127 colonies from 15 Brazilian localities were analyzed, using nine species-specific microsatellite primers. At these loci, the number of alleles ranged from three to 15 (mean: 7.2), and the observed heterozygosity (Ho) ranged from 0.03-0.21, while the expected heterozygosity (He) ranged from 0.23-0.47. The genetic distances among populations ranged from 0.03-0.45. The FST multilocus value (0.23) indicated that the populations sampled were structured, and the clustering analysis showed the formation of two subgroups and two more distant populations. The first group contained the subspecies M. quadrifasciata quadrifasciata, and the other, the subspecies M. quadrifasciata anthidioides and the two M. quadrifasciata populations with continuous metasomal stripes from northern Minas Gerais. These results confirmed that the yellow metasomal stripes alone are not a good means for correctly identifying the different subspecies of M. quadrifasciata.

4.
Biosci. j. (Online) ; 25(5): 112-119, sept.-oct. 2009. ilus, tab
Article in Portuguese | LILACS | ID: lil-545388

ABSTRACT

A principal fonte de abastecimento de água do município de Patrocínio/MG é o Córrego-Feio. Para conhecer as condições naturais deste manancial, 70 nascentes da bacia hidrográfica do Córrego-Feio foram diagnosticadas quanto ao estado de conservação de suas áreas de preservação permanentes (APP). Ações prioritárias de conservação ou recuperação das áreas foram recomendadas. As nascentes foram classificadas em três categorias: 14 nascentes (20%) foram classificadas como preservadas, 44 nascentes (63%) perturbadas e 12 nascentes (17%) como degradadas. Os principais fatores de perturbação observados foram os acessos de bovinos nas nascentes, a presença de plantas invasoras e o manejo inadequado dos solos no entorno das áreas de nascentes. Ações de conservação e recuperação devem priorizar o isolamento das áreas, reflorestamento das áreas degradadas e práticas adequadas de manejo e conservação no uso dos solos no entorno das nascentes.


The main source of water providement of Patrocínio city is the Córrego-Feio stream. To know the natural conditions of this supply, 70 risings of the hydrographic basin of the Córrego-Feio stream were diagnosed concerning the conservation state of its permanent preservation areas (PPA). Prioritary actions of conservation or recovering of the areas were recommended. The risings were classified in three categories: 14 risings (20%) were classified as preserved, 44 risings (63%) as disturbed and 12 risings (17%) as degradated. The main disturbing factors observed were the cattle access to the risings, the presence of invading plants and the inadequate handling of the soils in the risings surrounding areas. Conservation and recovering actions must priorize the isolation of the areas, reforestation of degradated areas and adequate practices of handling and conservation in the soils usage around the risings areas.


Subject(s)
Conservation of Natural Resources , Drinking Water , Hydrographic Basins , Water Recycling , Water Supply
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