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1.
Nature ; 628(8008): 563-568, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38600379

RESUMEN

More than a quarter of the world's tropical forests are exploited for timber1. Logging impacts biodiversity in these ecosystems, primarily through the creation of forest roads that facilitate hunting for wildlife over extensive areas. Forest management certification schemes such as the Forest Stewardship Council (FSC) are expected to mitigate impacts on biodiversity, but so far very little is known about the effectiveness of FSC certification because of research design challenges, predominantly limited sample sizes2,3. Here we provide this evidence by using 1.3 million camera-trap photos of 55 mammal species in 14 logging concessions in western equatorial Africa. We observed higher mammal encounter rates in FSC-certified than in non-FSC logging concessions. The effect was most pronounced for species weighing more than 10 kg and for species of high conservation priority such as the critically endangered forest elephant and western lowland gorilla. Across the whole mammal community, non-FSC concessions contained proportionally more rodents and other small species than did FSC-certified concessions. The first priority for species protection should be to maintain unlogged forests with effective law enforcement, but for logged forests our findings provide convincing data that FSC-certified forest management is less damaging to the mammal community than is non-FSC forest management. This study provides strong evidence that FSC-certified forest management or equivalently stringent requirements and controlling mechanisms should become the norm for timber extraction to avoid half-empty forests dominated by rodents and other small species.


Asunto(s)
Certificación , Agricultura Forestal , Bosques , Mamíferos , Animales , África Occidental , Biodiversidad , Peso Corporal , Conservación de los Recursos Naturales/legislación & jurisprudencia , Conservación de los Recursos Naturales/métodos , Elefantes , Agricultura Forestal/legislación & jurisprudencia , Agricultura Forestal/métodos , Agricultura Forestal/normas , Gorilla gorilla , Mamíferos/anatomía & histología , Mamíferos/clasificación , Mamíferos/fisiología , Fotograbar , Roedores , Masculino , Femenino
2.
FEMS Microbiol Ecol ; 59(3): 671-82, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17381520

RESUMEN

Filamentous Chloroflexi species are often present in activated sludge wastewater treatment plants in relatively low numbers, although bulking incidences caused by Chloroflexi filaments have been observed. A new species-specific gene probe for FISH was designed and using phylum-, subdivision-, morphotype 1851- and species-specific gene probes, the abundance of Chloroflexi filaments were monitored in samples from 126 industrial wastewater treatment plants from five European countries. Chloroflexi filaments were present in 50% of the samples, although in low quantities. In most treatment plants the filaments could only be identified with phylum or subdivision probes, indicating the presence of great undescribed biodiversity. The ecophysiology of various Chloroflexi filaments was investigated by a suite of in situ methods. The experiments revealed that Chloroflexi constituted a specialized group of filamentous bacteria only active under aerobic conditions consuming primarily carbohydrates. Many exo-enzymes were excreted, e.g. chitinase, glucuronidase and galactosidase, suggesting growth on complex polysaccharides. The surface of Chloroflexi filaments appeared to be hydrophilic compared to other filaments present. These results are generally supported by physiological studies of two new isolates. Based on the results obtained in this study, the potential role of filamentous Chloroflexi species in activated sludge is discussed.


Asunto(s)
Chloroflexi/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Administración de Residuos , Aerobiosis , Proteínas Bacterianas/clasificación , Proteínas Bacterianas/metabolismo , Técnicas de Tipificación Bacteriana/métodos , Metabolismo de los Hidratos de Carbono , Chloroflexi/clasificación , Chloroflexi/fisiología , Recuento de Colonia Microbiana , Sondas de ADN , Enzimas/clasificación , Enzimas/metabolismo , Genes Bacterianos/genética , Hibridación Fluorescente in Situ/métodos , Residuos Industriales/análisis , Datos de Secuencia Molecular , Filogenia , Aguas del Alcantarillado/análisis , Especificidad de la Especie
3.
Microbiology (Reading) ; 152(Pt 10): 3003-3012, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17005981

RESUMEN

The ecophysiology of five filamentous species affiliated to the Alphaproteobacteria was investigated in industrial activated sludge systems. The five species, 'Candidatus Alysiosphaera europaea', 'Candidatus Monilibacter batavus', 'Candidatus Alysiomicrobium bavaricum', 'Candidatus Sphaeronema italicum' and Meganema perideroedes, are very abundant in industrial wastewater treatment plants and are often involved in bulking incidents. The morphology of these filamentous bacterial species resembled Eikelboom's Nostocoida limicola, or Type 021N, and could only be correctly identified by using fluorescence in situ hybridization (FISH), applying species-specific gene probes. Two physiological groupings of the five species were found using microautoradiography combined with FISH. Group 1 ('Ca. Monilibacter batavus' and 'Ca. Sphaeronema italicum') utilized many short-chained fatty acids (acetate, pyruvate and propionate), whereas Group 2 ('Ca. Alysiosphaera europaea', 'Ca. Alysiomicrobium bavaricum' and Meganema perideroedes) could also exploit several sugars, amino acids and ethanol. All species had polyhydroxyalkanoate granules present and several of the species had a very large storage capacity. No activity was found under strict anaerobic conditions, while uptake of substrate was observed in the presence of nitrate or nitrite as potential electron acceptor. However, for all species a reduced number of substrates could be consumed under these conditions compared to aerobic conditions. Only a little exo-enzymic activity was found and nearly all species had a hydrophobic cell surface. Based on knowledge of the ecophysiological potential, control strategies are suggested.


Asunto(s)
Alphaproteobacteria/fisiología , Aguas del Alcantarillado/microbiología , Microbiología del Agua , Purificación del Agua , Aerobiosis , Alphaproteobacteria/clasificación , Alphaproteobacteria/citología , Alphaproteobacteria/genética , Aminoácidos/metabolismo , Anaerobiosis , Proteínas Bacterianas/análisis , Técnicas de Tipificación Bacteriana , Metabolismo de los Hidratos de Carbono , Gránulos Citoplasmáticos/química , Ecosistema , Enzimas/análisis , Etanol/metabolismo , Ácidos Grasos/metabolismo , Hibridación Fluorescente in Situ , Nitratos/metabolismo , Nitritos/metabolismo , Polímeros/análisis
4.
Syst Appl Microbiol ; 27(6): 716-27, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15612630

RESUMEN

The phylogeny and distribution of filamentous Alphaproteobacteria, morphologically similar to "Nostocoida limicola" and Eikelboom Type 021N that cause the solids separation problem of bulking in industrial activated sludge plants is described here. A combination of culture-dependent and culture-independent molecular methods has characterized 5 novel species. 16S rRNA targeted oligonucleotide probes were designed for their in situ identification by fluorescence in situ hybridisation (FISH) and used to monitor their presence in 86 WWTPs treating different industrial effluents in four European countries. The involvement of these bacteria in bulking in these plants was confirmed. Filaments hybridising with the ALF-968 probe for the Alphaproteobacteria were present in 65% of the WWTPs examined. They were dominant and therefore probably responsible for bulking in 25.5% of them. The heterogeneous filamentous alphaproteobacterial populations in these communities could be completely identified after application of the oligonucleotide probes used in this study in 91% of the plants containing them. The only filamentous Alphaproteobacteria retrieved in pure culture was isolated from three different industrial WWTPs plants. None of these isolates could grow anaerobically on glucose or denitrify, but all grew aerobically and heterotrophically on a range of carbon sources. Although morphologically similar to the Eikelboom Type 021N morphotype, they were not involved in sulphur metabolism. These bacteria accumulated lipidic storage granules that were associated with their presence under the unbalanced growth conditions existing in these plants.


Asunto(s)
Alphaproteobacteria/clasificación , Alphaproteobacteria/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Aerobiosis , Alphaproteobacteria/citología , Alphaproteobacteria/fisiología , Anaerobiosis , Metabolismo de los Hidratos de Carbono , Gránulos Citoplasmáticos , ADN Bacteriano/química , ADN Bacteriano/aislamiento & purificación , ADN Ribosómico/química , ADN Ribosómico/aislamiento & purificación , Europa (Continente) , Genes de ARNr/genética , Hibridación in Situ , Metabolismo de los Lípidos , Microscopía , Datos de Secuencia Molecular , Compuestos de Nitrógeno/metabolismo , Filogenia , ARN Bacteriano/análisis , ARN Bacteriano/genética , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Compuestos de Azufre/metabolismo , Microbiología del Agua
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