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1.
P. CUBAS H. TAHIRI C. PARDO 《Botanical journal of the Linnean Society. Linnean Society of London》2001,135(1):43-50
Karyological information on Cytisus species indicates at least two chromosome numbers for most of the taxa. This instability is, a striking karyological feature of Cytisus . Chromosome numbers of taxa in Sect. Spartopsis and Sect. Alburnoides, both well represented in Morocco and the Iberian Peninsula, are presented here. We provide the first data on chromosome numbers for the Moroccan taxa: C. grandiflorus subsp. barbarus , and subsp. haplophyllus (n = 23, 2 n = 46) , C. maurus (2 n = 48), C. megalanthus ( n = 23), C. arboreus subsp. arboreus , subsp. baeticus , and subsp. catalaunicus (2 n = 50), C. valdesii ( n = 23 ). New populations from the Iberian Peninsula have been counted: C. grandiflorus subsp. grandiflorus (2 n = 46), C. scoparius subsp. scoparius ( n = 23) , C. striatus subsp. eriocarpus ( n = 23, 2 n = 46), C. multiflorus (n = 23), C. oromediterraneus ( n = 23, 24). Our data confirm the instability of the chromosome number in Cytisus . The presence of B chromosomes in C. valdesii and C. megalanthus , as well in other species, is discussed in relation to this instability and previous data. We suggest that instability of the chromosome number within a taxon, and even in the same population, may be related to the breakage of A chromosomes and the appearance of B chromosomes. 相似文献
2.
SONIA BERNARDOS FRANCISCO AMICH FRANCISCA GALLEGO 《Botanical journal of the Linnean Society. Linnean Society of London》2003,142(4):395-406
Karyological information on Iberian Ophrys species is very limited. This paper provides the haploid and diploid chromosome numbers of 11 taxa of sect. Pseudophrys and sect. Ophrys , both of which are well represented in the Iberian Peninsula, and two taxa from Tunisia. The first data on chromosome numbers for O. vasconica (2 n = 72, 74), O. ficalhoana (2 n = 36), O. picta (2 n = 36), O. sphegifera ( n = 18, 2 n = 36, 38) and O. passionis (2 n = 36) are also presented, confirming the stability of the chromosome number in Ophrys . In addition, populations of the group O. omegaifera ( O. dyris and O. vasconica ), together with tetraploidy, pentaploidy and the existence of aneuploid phenomena, are reported for the first time in Iberia. The basic diploid number is always 2 n = 36. The karyotypes of several species were analysed. Evolutionary trends in Ophrys chromosomes are discussed. Taxonomic and phytogeographical details are provided on several species or groups of species from Iberia. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003 , 142 , 395−406. 相似文献
3.
David Corkill 《Ethnic and racial studies》2013,36(5):828-844
Within the last fifteen years Spain and Portugal have begun to experience a phenomenon that occurred in northern Europe three or four decades earlier. Rising prosperity, an ageing population, and growing labour shortages have triggered a demand for foreign labour in the Iberian economies. This survey article identifies the changing trends and developments of recent immigration to two southern European countries, and the problems of labour market integration. It compares and contrasts the insertion process in Spain and Portugal and highlights the policy dilemma that, like most of the rest of the EU, the Iberian economies require immigrant workers, but have yet to develop effective mechanisms for integrating them. It argues that the labour market is not only the principal mechanism by which immigrants are integrated, but is beginning to transform attitudes towards immigration. Employer organizations have played a lead role in pressing for a shift from restriction and control to the management of immigrant integration. However, the needs of employers, who require a supply of cheap, flexible labour clashes with the government's exclusion policy, as the case study based on Lorca, Spain demonstrates. 相似文献
4.
Pleguezuelos JM Santos X Brito JC Parellada X Llorente GA Fahd S 《Zoology (Jena, Germany)》2007,110(1):9-19
Eurosiberian vipers have been considered model organisms, and studies on their reproductive ecology have afforded much of the current knowledge concerning viviparity in snakes. However, such studies are biased towards northern species and there is little information on Mediterranean species and/or populations. The reproductive ecology of Vipera latastei in the Iberian Peninsula was studied by analysing a large sample of specimens from collections, to better understand the conservation status of this Mediterranean viper. Males and females matured at small and similar body sizes (240 and 265 mm snout-vent length, respectively) and reproductive cycles in both sexes were seasonal. Spermatogenesis peaked in August, vitellogenesis developed in spring and the timing of the mating period was puzzling, with populations mating in autumn, spring, or in both seasons. The most striking finding was that adult females reproduced triennially on average. Lataste's viper is currently in continuous decline in the IP, and most of its populations are isolated in Mediterranean mountains. We hypothesize that prey scarcity and the brevity of the activity period in mountain habitats diminishes the ability of vipers to recover over the short term the energy expended in reproduction. The species needs 2 years for the acquisition and storage of energy ("capital breeder"), and a third year for the expenditure of this energy (in vitellogenesis and embryogenesis), a year during which females feed consistently ("income breeder"). Thus, this viper combines both strategies to supply the reproductive energy cost. Current decline in population and distribution, together with a poor capacity to renew populations, renders Lataste's viper vulnerable to environmental stochasticity. 相似文献
5.
A general review is presented of the Carboniferous floral records in the Iberian Peninsula in the context of the geological history and distribution of the different basins. Mississippian floras are found in Sierra Morena, where major strike-slip faults brought in terranes of diverse provenance. Lower Pennsylvanian floras are represented in the Peñarroya-Belmez-Espiel (Córdoba) and Villanueva del Río y Minas (Sevilla) coalfields of SW Spain (also strike-slip controlled), at La Camocha, near Gijón (Asturias), and in other parts of northern Spain. Middle Pennsylvanian is represented near Oporto, but more completely in the Central Asturian Coalfield, as well as other, more limited localities in NW Spain and the Pyrenees. Upper Pennsylvanian (Stephanian Stage-Cantabrian to Stephanian B substages) floras are splendidly represented in NW Spain. Uppermost Pennsylvanian (Stephanian C-Autunian) floras are present in the strike-slip controlled Douro and Buçaco basins of North Portugal, the Pyrenees, Central Spain (Ciudad Real, Guadalajara, Zaragoza), and SW Spain (Guadalcanal and Valdeviar in Sevilla province).A complete succession of megafloral zones is presented. This includes a new Annularia spicata Zone at the top of the Pennsylvanian (equivalent to middle to upper Autunian which has been often attributed to the Lower Permian). The information is summarised in charts compiled from a selection of the most significant species. A number of floral elements are illustrated including the zonal indices. Brief taxonomic comments are provided in the Appendix. 相似文献
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7.
Francisco Díaz‐Ruiz Miguel Delibes‐Mateos José Luis García‐Moreno José María López‐Martín Catarina Ferreira Pablo Ferreras 《Mammal Review》2013,43(1):59-70
- Biogeographical diversity is central to the trophic ecology of predators. Understanding the biogeographical trophic patterns of generalist predators, such as the red fox Vulpes vulpes, is particularly challenging because of their wide distributions, broad trophic spectra and high ecological plasticity, which often generate conflicts with humans.
- We reviewed 55 studies from the Iberian Peninsula concerning the diet of the red fox to describe its trophic patterns from a biogeographical perspective.
- We considered the frequency of occurrence of seven food groups and characterized each study site according to environmental variables. We tested relationships between geographical variables and each food group independently, and assessed the consumption of lagomorphs in relation to the other food groups. We also tested the relationships between trophic diversity, the main food groups, latitude and altitude, and finally investigated changes in the consumption of all food groups in relation to habitat type and seasonality.
- We found a latitudinal pattern in the diet of the red fox, which was characterized by a greater consumption of lagomorphs and invertebrates in southern areas, and a higher intake of small mammals and fruits/seeds in northern regions. Additionally, the consumption of invertebrates increased from east to west, while fruit/seed consumption increased from west to east. Consumption of lagomorphs decreased, and of small mammals increased, with altitude. Trophic diversity was not associated with geographical variables. The intake of lagomorphs and small mammals was greatest in Mediterranean scrub and forest, respectively. Reptiles and invertebrates were consumed mostly during summer; fruits/seeds in autumn.
- Iberian red foxes show variation in their feeding habits associated with environmental variables, which are in turn associated with the availability of their main prey. Foxes select rabbits where they are abundant, and feed on small mammals and fruits/seeds where lagomorphs are scarce.
8.
The Iberian Peninsula represents a hot spot of cyphophthalmid (mite harvestman) disparity, with four of the eight genera currently recognized in the family Sironidae represented in the region – a generic diversity and morphological disparity not found in any other region of the World so far. From these, two genera (Iberosiro and Odontosiro) are monotypic, and are restricted to the western side of the peninsula. Parasiro is restricted to the north‐east region, from the Catalonian Coastal Ranges and both sides of the Eastern Pyrenees, in areas where the annual rainfall surpasses 1000 mm, and mostly restricted to areas with Paleozoic and Variscan rocks, with other species of the genus extending to Corsica, Sardinia, and the Italian Peninsula. A second species of the genus Paramiopsalis, Paramiopsalis eduardoi sp. nov. from Fragas do Eume, is described here along with a re‐diagnosis of the genus. Paramiopsalis species, together with Odontosiro, inhabit the north‐west corner of the Iberian Peninsula, an area with some of the highest recorded annual rainfall, and with Paleozoic rocks from the Iberian Massif or Variscan granitoid rocks. A phylogenetic analysis of the members of the family Sironidae using four molecular markers, despite not including all of the Iberian genera, clearly shows the non‐monophyly of the Iberian Cyphophthalmi, indicating that the Iberian Peninsula is home to multiple ancient lineages of mite harvestmen. The two Paramiopsalis species form a sister clade to the Balkan genus Cyphophthalmus, whereas Parasiro constitutes the first lineage of the sironids represented. 相似文献
9.
The Iberian Peninsula is one of the richest European regions in animal species diversity. Since 1988, the objective of the nationally funded Fauna Ibérica project has been to carry out a well-documented inventory of the animal biodiversity in the Iberian-Balearic region. After 10 years of taxonomic work, this project has produced 20 monographs, which have reviewed and inventoried around 11% of the animal species that inhabit the Iberian territory. It has also described 418 new species and 519 species formerly unknown in the Iberian-Balearic region. Considering all the new Iberian species described, we estimate that the researchers involved in this project have so far completed one third of all Iberian taxonomic work. At this rate it would take at least 75 years to finish the taxonomic review of the Iberian fauna. We recommend: (i) uninterrupted public logistical and financial support for taxonomy; (ii) the promotion of a plan for the training of new specialists in the taxonomically little-known groups; (iii) the elaboration of checklists as a way to inventory the Iberian animal biodiversity more rapidly; and (iv) the use of computerized approaches to species inventories taxonomy. 相似文献
10.
The eucalypt‐feeding psyllid Glycaspis brimblecombei Moore (Hom.: Psyllidae), an Australian insect, is reported for the first time in Europe. It was initially detected in Portugal and Spain, in September 2007, on Eucalyptus camaldulensis Dehn. At present, G. brimblecombei has only been found associated with E. camaldulensis and E. tereticornis Smith, being apparently absent from E. globulus Labill., the main eucalypt species planted on the Iberian Peninsula. Generalist predators, such as ants, spiders and ladybeetles, were observed in trees attacked by G. brimblecombei, but no psyllid parasitoids were detected. 相似文献
11.
Herbaceous plant richness and vegetation cover in Mediterranean grasslands and shrublands 总被引:1,自引:0,他引:1
Casado Miguel A. Castro Isabel Ramírez-Sanz Lucía Costa-Tenorio Margarita de Miguel Jose M. Pineda Francisco D. 《Plant Ecology》2004,170(1):83-91
Different types of relationship between herbaceous species richness and several parameters indicating abundance of plant material (herbaceous, woody plants, litter and bare ground cover) are presented. The data were obtained from 50 sites along a 300 km strip running from E to W within Spain and Portugal. Each site was representative of the silvo-pastoral landscape of the Mediterranean type ecosystems of the Iberian peninsula, and contained two neighboring patches, one of grassland and the other of shrubland. 3,600 20 × 20 cm subplots were randomly located (72 per site, 36 per patch) crossing the boundary grassland/shrubland. This approach allowed us to analyze the richness-occupation relationship of the space from different points of view: among and within the sites, and among and within the grassland and shrubland plant communities. We found a unimodal relationship between richness-cover similar to the one generally accepted between richness and biomass. Our results show that the dependence of this relationship varies depending on the spatial scale of the analysis and on the type of data used. When the whole region is taken into account, significant unimodal relationships are found between richness and herbaceous cover, litter and bare ground, and a negative linear relationship with woody plant cover. Within the sites there are mainly linear or non-significant relationships. But the results also depend on the type of communities analyzed. In pastures, the unimodal relationship represents the combination of positive and negative linear responses for low and high cover values, respectively. The value for herbaceous cover in which maximum richness occurs is around 60%. In shrublands, this value for cover also corresponds to maximum species richness, although the possibilities of reaching it are limited by other variables, such as woody plant cover. This implies that, on not considering variability at local scale, the relationship is linear and positive. This paper shows the existence of a common model related to herbaceous cover, but this model has multiple controlling factors that act differently in each type of community. 相似文献
12.
国产蕺菜的染色体数目变异及核穿壁现象 总被引:6,自引:0,他引:6
蕺菜 Houttuynia cordata Thunb.属三白草科蕺菜属,俗称鱼腥草、侧耳根等,主要分 布于 亚洲东部和东南部,我国以长江流域及其以南各省区常见。蕺菜药蔬兼用,为极具开发前景 的植物资源。部分学者曾对蕺菜染色体数目进行过报道,但报道的染色体数目不尽一致(梁汉兴,1991,1995; Hsu,1968; Nilsamranchit et al, 1999),并且对此 现象未作较为详细而深入的解释。本文对国内部分省区收集的蕺菜种质资源进行染色体数目分析,旨在从细胞学角度探讨蕺菜的遗传多样性,为 相似文献
13.
To protect native biodiversity and habitats from the negative impacts of biological invasions, comprehensive studies and measures to anticipate invasions are required, especially across countries in a transfrontier context. Species distribution models (SDMs) can be particularly useful to integrate different types of data and predict the distribution of invasive species across borders, both for current conditions and under scenarios of future environmental changes. We used SDMs to test whether predicting invasions and potential spatial conflicts with protected areas in a transfrontier context, under current and future climatic conditions, would provide additional insights on the patterns and drivers of invasion when compared to models obtained from predictions for individual regions/countries (different modelling strategies). The framework was tested with the invasive alien plant Acacia dealbata in North of Portugal/NW Spain Euro-region, where the species is predicted to increase its distribution under future climatic conditions. While SDMs fitted in a transfrontier context and using “the national strategy (with Portugal calibration data) presented similar patterns, the distribution of the invasive species was higher in the former. The transfrontier strategy expectedly allowed to capture a more complete and accurate representation of the species’ niche. Predictions obtained in a transfrontier context are therefore more suitable to support resource prioritisation for anticipation and monitoring impacts of biological invasions, while also providing additional support for international cooperation when tackling issues of global change. Our proposed framework provided useful information on the potential patterns of invasion by A. dealbata in a transfrontier context, with an emphasis on protected areas. This information is crucial for decision-makers focusing on the prevention of invasions by alien species inside protected areas in a transfrontier context, opening a new way for collaborative management of invasions. 相似文献
14.
FRANCISCO AMICH JUAN A. DEVESA SONIA BERNARDOS 《Botanical journal of the Linnean Society. Linnean Society of London》2004,144(3):351-364
A revision of the three endemic Iberian species of Succisella G. Beck ( S. carvalhoana , S. microcephala and S. andreae-molinae ), based on herbarium studies, SEM photographs and field observations, is presented utilizing morphological, palynological, karyological, biogeographical and ecological characters. The distribution of the species in the Iberian Peninsula is shown in a grid map. Full synonymy is given for all taxa. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 351–364. 相似文献
15.
H. Graf F. Sokolowski A. Klewer E. Diederichsen H. Luerßen & J. Siemens 《Journal of Phytopathology》2001,149(6):313-318
Classical genetic analysis is not possible with the protist Plasmodiophora brassicae due to the intracellular life of this obligate biotrophic parasite . An electrophoretic karyotype has been obtained using contour-clamped homogeneous electric field gel electrophoresis to facilitate gene mapping of P. brassicae. Using two different separation conditions 16 chromosomal bands of P. brassicae were distinguished ranging in approximate size from 2.2 Mb to 680 kb. According to this determination of chromosome number and size, the total genome size of P. brassicae was estimated to be 20.3 Mb. The chromosomal bands were further designated by their hybridization pattern with repetitive elements of P. brassicae . The repetitive element H4 (1800 bp) hybridized with 14 chromosomal bands, but the sequence of H4 showed no homology to known centromere or telomere structures and revealed no repetitive motifs. 相似文献
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17.
Raccoons are American carnivores, considered invasive across several countries worldwide, especially in Europe. In the Iberian Peninsula, previous studies on raccoons documented several breeding populations in Spain a decade ago and only two confirmed records from isolated individuals in Portugal. Given the need for updating its Iberian distribution and identifying suitable areas with higher invasion risk, we compiled presence records from established breeding populations and isolated individuals. By using a Maxent approach based on breeding records, we forecasted the suitable habitats in Iberia with higher invasion risk for raccoons and identified the related environmental drivers. Overall, we collected 1039 records of raccoon presence throughout the Iberian Peninsula, including 980 records from established breeding populations. Their origin is probably linked to escapes from captivity. Climatic conditions, linked to both drier and wetter environments, and proximity to water bodies were the main predictors of suitable areas for raccoon’s expansion from the currently established breeding nuclei in Iberia. The forecasted high probability areas showed a wide, but fragmented distribution concentrated on four main areas: central, central-north, central-east, and north-west Iberia. NW Portugal seems to be the area with higher invasion risk in the country, although field surveys showed no evidence of raccoon presence yet. However, there are several records in Spain near the Portuguese border, comprising isolated individuals and breeding populations. Therefore, it is crucial to ensure regular monitoring of areas with high invasion risk, particularly those near facilities with captive raccoons that often act as a source of feral individuals, to assure early detection and effective control for the expansion of this invasive carnivore. 相似文献
18.
C. Sérgio C. A. Garcia M. Sim-Sim C. Vieira H. Hespanhol S. Stow 《Journal of bryology》2017,39(1):1-7
Previous molecular studies have done much to shed some light on the taxonomy and phytogeographic position of Homalothecium sericeum and H. meridionale and the present study clarifies the taxonomy and distribution of the two species across Iberia. By conducting a revision of Homalothecium specimens available in Spanish and Portuguese herbaria, we concluded that sporophytic differences are the most appropriate characters for the delimitation of each species. Scanning electron microscope examination of the peristomes of the two taxa helped distinguish between them.
We also noted that H. meridionale is a frequently distributed taxon throughout the Iberian territory, but occurs mostly in Portuguese areas with a Mediterranean influence, becoming less frequent in the Atlantic as well as in continental parts of the Peninsula. As a result of this study, based on numerous new localities in Portugal and Spain, we provide an updated map of the distribution of H. meridionale, and an account of its ecology and habitat affinities. 相似文献
19.
国产十四种苋属植物的染色体数目 总被引:5,自引:0,他引:5
报道了国产14种苋属植物的染色体数目。部分种的染色体数目为2n=34,即反枝苋Amaranthus retroflexus,刺苋A.spinosus,红苋A.cruentus,腋花苋A.roxburghianus,合被苋A.polygonoides,皱果苋A. viridis,凹头苋A.lividus,苋A.tricolor。其他种的染色体数目为2n=32,即尾穗苋A.caudatus,绿穗苋A. hybridus,千穗谷A.hypochendriacus,繁穗苋A.paniculatus,北美苋A.blitoides,白苋A.albus。其中腋花 苋的染色体数目为首次报道。该属染色体基数为x=16,17。两种染色体基数在苋属2个组(sect.Ama- ranthus和sect.Blitopsis)中均存在。由于苋属植物染色体大多为小型染色体,因此对苋属植物目前尚不 能进行详尽的核型分析。 相似文献
20.
DANIEL DE AZKUE 《Botanical journal of the Linnean Society. Linnean Society of London》2000,132(2):143-152
Mitotic or meiotic chromosome studies are reported for 39 species or subspecies of Oxalis from South America belonging to 14 sections. Chromosome numbers of 34 of these taxa are reported for the first time. Diploids and polyploids with six different basic chromosome numbers x=5, 6, 7, 8, 9 and 11 are described. Thirteen species of subgenus lhamnoxys were analysed and two new basic chromosome numbers were observed in diploid entities of this subgenus, x = 6 and x=9. The underground stem-bearing entities of Oxalis subgenus Oxalis studied (in sections Articulatae, Jonoxalis and Palmatifoliae) are mostly diploids and polyploids with a basic chromosome number x=7. Five species of section Carnosa are diploids with x = 9. In species of sections Rosea, Ortgieseae, Clematodes and Laxae the basic chromosome numbers x = 6, 7, 8 and 9 were observed. Groups of related species sharing the same chromosome number are discussed with the aim of improving the infrageneric delimitation of the genus. The basic chromosome number x=6 seems to be primitive in the genus and other basic chromosome numbers probably appeared several times in the course of chromosome evolution of Oxalis . 相似文献