Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Environ Entomol ; 49(4): 947-955, 2020 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-32533159

RESUMEN

In the context of global pollinator decline, little is known about the protection status and ecology of many species. This lack of knowledge is particularly important for Mediterranean protected areas that harbor diverse pollinator communities and are subject to considerable anthropogenic pressures. Calanques National Park (85 km2), which is located near Marseille (France), is dominated by Mediterranean low-vegetation habitats, such as phrygana and scrublands. These habitats offer favorable conditions for pollinator species due to the important amount of floral resources. Within a 10-yr period, we recorded bee (Hymenoptera: Apoidea: Anthophila), hover fly (Diptera: Syrphidae), and bee fly (Diptera: Bombyliidae) species and their interactions with the local flora through 10 field campaigns. We caught 250 pollinator species, including 192 bees, 38 hover flies, and 20 bee flies, for a total of 2,770 specimens. We recorded seven threatened bees (six near threatened and one endangered). Among the bee species, 47.9% were below-ground nesting species, and 54.7% were generalist species. Analysis of the pollination network showed that generalist and specialist pollinators do not share the same floral resources. The Cistaceae plant family (Malvales: Cistaceae) acted as a central node in the plant-pollinator network, interacting with 52 different pollinator species, which shows the importance of large open flowers that could be easily visited by both short and long-tongued pollinators in Mediterranean habitats. The occurrence of pollinator species and their ecological traits should strongly contribute to reinforcing the available information to provide or ameliorate the conservation statuses determined by IUCN Red List.


Asunto(s)
Ecosistema , Polinización , Animales , Abejas , Flores , Francia , Plantas
2.
C R Biol ; 333(10): 744-54, 2010 Oct.
Artículo en Francés | MEDLINE | ID: mdl-20965444

RESUMEN

The study of two pollen sequences from El-Kala marshes allowed the reconstruction of the regional vegetation history supported by eight radiocarbon dates. Pollen assemblages from Bourdim site were dominated by local input of Alnus and Salix, while regional vegetation was characterized by scattered Quercus suber forests with a well-developed Erica arborea matorral. While the vegetation dynamics recorded at Bourdim is recent (Late Holocene), the majority of the pollen diagram from Garaat El-Ouez is contemporaneous to the Late Pleniglacial and is characterized by open woodlands with Pinus, Poaceae and several heliophilous herbs. The significant values of Cedrus pollen identified in this period indicate that the region of El-Kala most probably played the role of a refugium for this tree.


Asunto(s)
Polen , Árboles , Humedales , Argelia , Cedrus , Cambio Climático , Ecosistema , Sedimentos Geológicos/análisis , Historia Antigua , Pinus , Poaceae , Polen/química , Quercus , Datación Radiométrica , Árboles/crecimiento & desarrollo
3.
C R Biol ; 328(7): 661-73, 2005 Jul.
Artículo en Francés | MEDLINE | ID: mdl-15992749

RESUMEN

This paper presents a pollen diagram from La Beunaz peat-bog (southeast of Evian, Haute-Savoie, France), which provides the first detailed record of human impact on vegetation of the southern bank of Lake Geneva since the Middle Neolithic. The radiocarbon-dated pollen profile is correlated with micro-charcoal record and archaeological data. The results suggest that several phases of deforestations since 4615+75/-70 years BP occurred, in relation to human activities (agriculture, pastoralism). Tombs and vestiges of lacustrine villages indicate that the region was intensively and recurrently occupied by man during at that time.


Asunto(s)
Fósiles , Fenómenos Fisiológicos de las Plantas , Polen/fisiología , Radioisótopos de Carbono/análisis , Demografía , Ambiente , Francia , Geografía , Germinación , Desarrollo de la Planta
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...