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31.
Matías Reolid Christian Gaillard Federico Olóriz Francisco J. Rodríguez-Tovar 《Facies》2005,50(3-4):529-543
Two main types of microbial encrustation were identified in Middle Oxfordian to lowermost Kimmeridgian deposits in the Prebetic Zone (southern Spain), showing existing relationships between skeletal content, fabric and morphology of these organosedimentary structures. Laminated planar and concentric encrustations relate to peloidal fabrics (mainly constituted of microbes = microbial laminated fabrics s. str. and microbial oncoids s. str.), as well as to dense microbial fabrics periodically colonized by encrusting foraminifera (microbial laminated fabrics with nubeculariids and microbial oncoids with nubeculariids). Sedimentation rates, substrate stability and grain size, as well as illumination, influenced microbial growth pattern as major controlling factors in low-energy conditions, and forced palaeogeographic and stratigraphic patterns of distribution. Significant encrustation was identified in terrigenous-poor lithofacies from the middle (Transversarium-Bifurcatus zones) to the outer (Transversarium-Bimammatum zones) shelf in the Prebetic Zone. Rare-to-absent encrustation characterized terrigenous-rich deposits (Bimammatum and Planula zones) in the area. 相似文献
32.
33.
Historical Ecology on Sandoy, Faroe Islands: Palaeoenvironmental and Archaeological Perspectives 总被引:1,自引:1,他引:0
Ian T. Lawson Mike J. Church Tom H. McGovern Símun V. Arge James Woollet Kevin J. Edwards Freddy J. Gathorne-Hardy Andrew J. Dugmore Gordon Cook Kerry-Anne Mairs Amanda M. Thomson Guðrún Sveinbjarnardótti 《Human ecology: an interdisciplinary journal》2005,33(5):651-684
We present palaeoenvironmental, geomorphological, archaeological, and place-name data which allow a holistic assessment of
the history of landscape change on Sandoy, Faroe Islands, especially in terms of the changes that occurred in response to
the colonization of the island by humans. In contrast to other situations in the North Atlantic region, there is considerable
continuity in the patterns and processes of landscape evolution across the initial settlement horizon. Many of the characteristic
features of post-settlement North Atlantic landscapes—absence of trees, widespread blanket mires, high rates of soil erosion—were
already in place when the first people arrived. Although human impact on Sandoy appears to have been light, conversely, the
unusual environment forced major alterations of the subsistence economy imported by the colonists. Settlement-era archaeological
records suggest that, from the start, patterns of resource use differed substantially from the regional norm, and these differences
became amplified over time as the Faroese economy created a locally sustainable cultural landscape. 相似文献
34.
Population structure in the Atlantic salmon: insights from 40 years of research into genetic protein variation 总被引:5,自引:0,他引:5
35.
In total, seven ciliate species were recorded in leaf-litter, moss and soil from a variety of sites in Slovakia for the first
time: Chilophrya terricola Foissner, 1984; Holostichides typicus (Song et Wilbert, 1988) Eigner, 1994; Keronella gracilis Wiackowski, 1985; Notoxoma parabryophryides Foissner, 1993; Parafurgasonia sorex (Penard, 1922) Foissner et Adam, 1981; Paragonostomum multinucleatum Foissner, Agatha et Berger, 2002, and Territricha stramenticola Berger et Foissner, 1988. The paper deals with their distribution, ecology, and comparison with similar species. The shape
and nuclear variants of Paragonostomum multinucleatum are presented and populations of P. multinucleatum and T. stramenticola are morphometrically characterized. 相似文献
36.
New chromosome numbers for two species from the Senecio nemorensis group: S. dacicus (2n = 40) and S. ucranicus (2n = 40) have been ascertained. The counts for S. germanicus
Wallr. subsp. germanicus (2n = 40), S. hercynicus Herborg subsp. hercynicus (2n = 40), S. ovatus (P. Gaertn. et al.) Willd. subsp. ovatus (2n = 40) occurring in the Carpathians are also reported. The study confirmed only the known tetraploid chromosome number for
the taxa of this group. The pollen fertility ranged from 82.09 to 92.99% in all examined species and subspecies, including
their hybrids. 相似文献
37.
38.
Manuel Pardo-de-Santayana Javier Tardío Michael Heinrich Alain Touwaide Ramón Morales 《Economic botany》2006,60(2):159-181
El Ingenioso Hidalgo, Don Quijote de la Mancha, by Miguel de Cervantes (1547–1616), is the best-known work of Spanish literature. We searched this and the other works of Cervantes for references to plants, plant communities, and products. These texts capture the customs, thoughts, beliefs, and traditions of Spanish culture in the late 16th and early 17th centuries. They also repeat literary themes of ancient Greek and Roman literature. Plant citations were grouped in three categories: plants as part of the environment, useful plants, and plants in symbolic expressions. A total of 150 species were registered, 102 of which appear inDon Quijote. The taxa with the highest frequency of occurrence areVitis vinifera, Phoenix dactylifera, Triticum aestivum, Laurus nobilis, Rosa spp.,Olea europaea, Quercus ilex, andArundo donax. The number of references to plants and the variety of species seem to attest to a sound and intimate knowledge of plants, their relevance as a landscape feature, and their utility. Many edible, ornamental, technological, and medicinal plants are referred to either explicitly or implicitly. Several species are mentioned in a figurative sense through references to their symbolic meaning, in proverbs, idiomatic expressions, metaphors, or by mentioning them in comparisons and literary figures of speech. 相似文献
39.
Sílvia G. Pereira Fernando P. Lima Nuno C. Queiroz Pedro A. Ribeiro António M. Santos 《Hydrobiologia》2006,555(1):185-192
Geographical patterns in the distribution of epifaunal crustaceans (Amphipoda, Isopoda and Tanaidacea) occurring with dominant
macroalgal species were investigated along the Portuguese rocky coast. Three regions, each encompassing six shores, were studied.
Algal species were selected according to their geographical distribution: Mastocarpusstellatus and Chondrus crispus (north); Bifurcariabifurcata (north-centre); Plocamiumcartilagineum and Cystoseiratamariscifolia (centre-south); Corallina spp. and Codiumtomentosum (entire coast). Multivariate techniques were used to test for differences in crustacean assemblage composition between sub-regions
and host algal species. A clear gradient of species substitution was observed from north to south. Differences in abundance
and diversity of epifaunal crustaceans were observed between southern locations and the remaining sites. Four species were
recorded for the first time in the Portuguese coast. Among the 57 taxa identified, southern distribution limits were observed for three species and northern distribution limits were observed for
four species. Interestingly, the observed geographical patterns in epifaunal abundance and diversity were not related with
geographical changes in the indentity of the dominant algal species. 相似文献
40.
The European rewardless, bee-pollinated orchidDactylorhiza sambucina commonly produces yellow-flowered and purple-flowered individuals in frequencies that range from balanced (per population) to very unbalanced, with parts of the species’ range entirely monochromatic. We studied male and female reproductive success of the two morphs in 22 populations in the Czech Republic, relating it to morph frequency, population size and density, and presence and abundance of yellow and purple co-flowering nectar-providing species visited by the same bee species. Cumulative abundances of yellow nectar-producing co-flowering species (of which, on average,Primula veris made up 56%) had a negative effect on male reproductive success of the yellow morph, and spectral analyses showed that to bumblebees the colours ofP. veris and yellowD. sambucina are different, permitting ready visual discrimination. The cumulative abundance of purple co-flowering species had no significant effect on morph reproductive success. Morph frequencies were unrelated to reproductive success and population size, and there was no evidence of frequency-dependent selection except in one highly unbalanced population. Density of flowering conspecifics was negatively correlated with male reproductive success of the purple morph. Seed mass, viability, and germination success depended on whether seeds resulted from outcrossed or selfed matings and on morph colour. Selfed seeds and seeds produced by the yellow morph from yellow × yellow and yellow × purple crosses had zero germination (after three months), providing the first hint that differential vegetative fitness, rather than differential reproductive fitness via pollinator selection, may explain morph frequencies inD. sambucina. 相似文献