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1.
A new subspecies,A. grandiflora subsp.gomarica (Caryophyllaceae), is described from the mountains of northern Morocco. The new taxon is tetraploid and has been confused in the past either with the Balearic endemicA. grandiflora subsp.glabrescens or with the widespreadA. grandiflora subsp.grandiflora, which is also present in the African continent. Detailed morphological analysis showed that plants from the Rif mountains are closely related toA. grandiflora subsp.glabrescens, but differ from it in having a longer calyx, smaller seed size, and a glandular indument on pedicels, leaves and calyx.Arenaria grandiflora subsp.gomarica can be distinguished from all infraspecific taxa of theA. grandiflora complex by the combined presence of a heterotrichous (simple and pluricellular eglandular hairs, glandular hairs) indument on the inflorescences and glandular hairs on the calyx.  相似文献   

2.
Data are presented on intergroup interactions between six groups of Macaca sylvanus in the Ghomaran region of the Moroccan Rif mountains. Intergroup encounters (0.026/observation hour) were defined as two groups being near each other (< 150 m). Encounters were further classified into: 1) neutral (indeterminate) encounters, in which very little intergroup interaction took place, with the exception of male monitoring (N = 7); 2) approach-retreat encounters with intergroup displacement, in which, without any overt agonism, members of one group slowly approached another and caused it to retreat (N = 3); and 3) agonistic encounters with intergroup displacement (N = 3). These results are compared to the only other study of intergroup interactions in wild Barbary macaques, and it is concluded that 1) observations of intergroup unification and/or coordination of movement in Barbary macaques (“herding”) probably resulted from observer error, or if these phenomena do occur, they are rare throughout the range of this species; 2) approximately half of all intergroup encounters in both studies resulted in intergroup displacement and/or intergroup agonism, evidence of intergroup competition; and 3) current data on intergroup interactions in Barbary macaques conform to the predictions of Wrangham's model of mutually competitive female-bonded, multimale groups.  相似文献   

3.
A pollen diagram was constructed for the early- to mid-Holocene transition (ca. 7350–5600 cal. b.p./5400–3650 b.c.) from the Burmarrad ria located in NW Malta. The vegetation at ca. 7350–6960 cal. b.p./5400–5010 b.c. was characterized by an almost tree-less steppe-like open landscape. Early Holocene dry climatic conditions were most probably due to intensification of the subtropical monsoon circulation that strengthened the subtropical anticyclonic descent over the central Mediterranean and blocked the penetration of humid air masses from the North Atlantic Ocean. At ca. 6950 cal. b.p./5000 b.c., the steppe-like vegetation was suddenly replaced by a Mediterranean evergreen forest or dense scrub dominated by Pistacia cf. lentiscus trees. This event, which has simultaneously been recorded in southern Sicily, was most probably caused by the southward shift of the ITCZ permitting the eastward movement of the North Atlantic cyclonic systems. Traces of human activities are evident in the pollen diagram since the beginning of the record but become more pronounced from the onset of the Temple Cultural Phase at ca. 6050 cal. b.p./4100 b.c. with a gradual decline of tree pollen. We suggest that the early- to mid-Holocene vegetation transformation was mainly controlled by a regional climatic change that occurred in a landscape only slightly impacted by human activities.  相似文献   

4.
A new species ofFumana (Dunal) Spach subgenusFumana, F. fontqueri, is described from the region of Rif, Morocco. Notes on its morphology, ecology, distribution and taxonomic relationships are presented. It differs fromF. procumbens (Dunal) Gren. etGodr. andF. baetica Güemes, by the indument of the stem, the disposition of pedicels, and the size of the flowers.  相似文献   

5.
At the north-western limit of the Mediterranean basin, in the Mediterranean-Oceanic transition zone, the multidisciplinary study of two palaeolakes: Villaseca and La Mata (Province of Leon), provides data on the last deglaciation. The juxtaglacial lakes were formed during a deglaciation phase of the last cold stage (Weichselian/Würm) estimated, from the regional and Pyrenean chronological data, between circa 48 ka and 32 ka (ka: 1000 years ago). Their drainage occurred circa 17 ka and 15 ka respectively, during the definitive glacial retreat phases. These results provide evidence for a glacial maximum extension preceding the global Last Glacial Maximum (LGM) and an early deglaciation. Comparisons with the Pyrenean data show that in the most important glacial basins of the Pyrenean-Cantabrian range, glaciers were still present at middle elevation circa 18-20 ka. The final deglaciation did not happen until around 16 ka.During the period 48-13.3 ka, along the Pyrenean-Cantabrian range, three stages can be distinguished in the deglacial processes. Between circa 48 and 32 ka, the deglacial retreats were contemporaneous with D-O events 12 to 6. Between circa 32 ka and 18 ka, major sedimentary modifications were rare. Two of them are synchronous with D-O 4 and 3. A glacial readvance also occurred during this period along the Pyrenean-Cantabrian range. Between 18 and 17 ka, major sedimentary changes and an increase in the δ18O records of the NGRIP ice-core record are synchronous. Between 15 and 13.3 ka, glacial retreats and sedimentary changes are synchronous with the climatic improvement observed from the end of the Oldest Dryas to the end of the Bölling-Alleröd period.These correspondencies suggest relationships between the deglacial processes in the western Mediterranean and the palaeoenvironmental events in the North Atlantic region during the last Glacial-Interglacial transition. During the Full Glacial period, the pollen data indicates dominant steppic environments. The Oldest Dryas was not a constant cooling phase and from around 15.5 ka, the pollen data indicates a slight warming. During the Holocene, until circa 2040 cal BP, mixed oak forests developed and pine was a prominent component of the Cantabrian landscape. Then the forests were destroyed due to mining, agriculture and fire, and this favoured the extension of heathland.  相似文献   

6.
A sero-epidemiological survey has been conducted in several localities of the province of Nador to investigate canine leishmaniasis in the North-Eastern slope of the Rif mountains (Mediterranean coast of Morocco). Serum samples collected from 257 dogs were analysed using indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) to detect anti-Leishmania infantum antibodies. Forty eight (18.7%) of the screened dogs were IFAT positive and 54 (21.0%) were ELISA positive; the concordance of the two methods was 96.1%. The prevalence of infection is significantly higher in dogs more than four years of age whereas no significant difference in prevalence of infection was seen between males and females. The frequent symptoms observed in seropositive dogs were the enlargement of lymph nodes (57.4%), emaciation (51.9%) and skin involvement (25.9%). However, 38.9% of those dogs showed no one of the major symptoms of visceral leishmaniasis. Leishmania isolated from three of the examined dogs was identified as L. infantum MON-1. These results show that the North-Eastern slope of the Rif mountains is one of the most active Mediterranean areas of visceral leishmaniasis and confirm that the dog is the main reservoir of L. infantum.  相似文献   

7.
Appropriate management of contemporary environments requires knowledge of their long-term history. We use palaeoecological data to explore how contemporary forest-steppe environments have been shaped by climate change and human impacts through the Holocene using the western Mid-Russian Upland as a case-study. Our paper presents new reconstructions of Mid- and Late Holocene climate, vegetation dynamics and local environmental change based on pollen, plant macrofossil and testate amoeba records from a site at Selikhovo (Mid-Russian Upland, Russia). Eutrophic fen vegetation dominated by Phragmites australis developed around 6800 cal year BP and has been resilient to episodes of local burning and variable input of mineral material through the Holocene. New and previously-published data show that the boundary between broadleaf forest and steppe occupied a similar position to present during the period 7000–4800 cal year BP, despite a warmer and drier climate, but shifted to the south following climate cooling and an increase in precipitation from 4800–2500 cal year BP. A subsequent decline in woodland cover was caused by both climate change and human impacts, with human activity becoming increasingly significant over the last two millennia. Prior to major human disturbance (about 1700 cal year BP) the landscape was dominated by mixed broadleaf-pine forests with some spruce covering about 60 % of the study area. Our results emphasize the variability of steppe-forest habitats over long time periods and the need to consider human impacts and climate change when setting targets for habitat conservation.  相似文献   

8.
Ascospores are frequently found as airborne fungal spores and recognized in various areas as an important cause of respiratory allergies. The main objective of the study was to determine the relationship between airborne ascospores and meteorological parameters using multivariate canonical correspondence analysis (CCA) and Spearman correlation. The aerobiological monitoring of fungal spores was performed over 5 years (2009–2013) using a Burkard volumetric spore traps. Seven main types of ascospores were identified: Leptosphaeria, Pleospora, Venturia, Diatrype, Chaetomium, Sporormiella and Ascobolus. The CCA results showed that all applied variables accounted for 27.4 % of the total variance in the spore data in the 5 years. The largest contribution to the total variance was explained in this period by the maximum air temperature (10.3 %). The effect of meteorological factors varied among years. The highest values of the total variance in the spore data, explained by the statistically significant variables, were observed in 2012 (28.6 %), with the highest contribution to minimum relative humidity (8.0 %). Most ascospores showed positive and statistically significant correlation with relative humidity and rainfall. In contrast, ascospores of Chaetomium were negatively correlated with precipitation and the relative humidity and positively with temperature. Based on these results, epidemiological and allergological studies must deserve more attention to estimate the allergenic potential of the ascospores.  相似文献   

9.
A small geographically isolated population of the Barbary macaque inhabits a high-altitude fir forest habitat ( Abies pinsapo ) in the Ghomaran region of the Rif mountains of northern Morocco. The climate of this region is Mediterranean, but the altitude (1600–2100 m) causes winters to be cold (as low as -8.0 C) with snow occurring from November to May (snowfall as deep as 1.5 m). The primary winter feeding adaptation is the ability to ingest high quantities of fir foliage; in spring, the macaques took a high diversity of leafy food items from all vegetation layers; in summer, the macaques foraged terrestrially for a high diversity of food items including seeds, small fruits, bulbous geophytes, and animal foods (including tadpoles from small streams); in autumn, the macaques returned to arboreal foraging, primarily feeding on oak acorns ( Quercus ilex ), fir seeds and yew fruit ( Taxus baccata ). The macaques were capable of ingesting 100 of 195 (51%) of all identified plant species in the region, although during the four-month winter, the macaques only averaged 12.5 common food items. A comparison of the study area with the prime habitat of the Barbary macaque-the high-altitude cedar forests of the Moroccan Moyen Atlas-indicates that climate and vegetation physiognomy are highly similar in both regions. Correspondingly, there is a high degree of similarity in macaque diet in both regions in terms of feeding behaviour by season, food diversity and specific feeding techniques. In the Ghomara, the winter feeding adaptation of fir foliage eating parallels that of the Barbary macaque in cedar forest (winter foraging for cedar foliage). This enables the Barbary macaque to exploit the Ghomaran fir forest habitat during the cold, snowy winters much the same as it does cedar forest habitat throughout a major portion of its geographical range.  相似文献   

10.
The Tamezzakht succession (Maastrichtian–middle Burdigalian), situated at the fringe between the Internal and the External zones, displays contrasting lithologies with abrupt facies changes, discontinuities, and/or coarse-grained calciturbidite in between. These criteria allow the definition of seven main lithostratigraphic formations.Depositional environments (oxygenation levels, trophic conditions, omission histories, among others) and/or transgressive/regressive trends are inferred from integrated sedimentologic data including facies change, cyclicity pattern and the textural composition of the turbidite facies tracts. Special emphasis is given to the ichnological features.Taking into account the extended time-range, the position between the internal zones and the external ones, as well as the clear differentiation into several contrasting sedimentary formations, the Tamezzakht succession is expected to provide useful stratigraphic data for the regional correlations.  相似文献   

11.
The pollen spectra in 18 honey samples from the Gharb region (Northwest of Morocco) have been studied. The samples were collected directly from the beekeepers, both professional and amateurs. The results show that nectar was the main honey source in this region, although one forest or mixed honey was detected. Seven samples belonging to the Class I, five to the Class II and six to the Class III were found. In all the samples some honeydew indicator elements were detected, with HDEN/NPGN= 0.005-1.38. By the qualitative results 58 pollen types belonging to 28 families were identified. Some species of Lythrum , Eucalyptus , Trifolium , Citrus , Mentha , Apiaceae and Scrophulariaceae are the main nectar sources,and some of Asteraceae, Quercus sp., Olea europaea , Plantago sp. and Fragaria 2 ananassa are the most important pollen sources. At least 14 unifloral honeys (c. 77%) from Citrus , Eucalyptus , Lythrum , Mentha and Teucrium were detected.  相似文献   

12.
The present work refers to the pollen analysis of 35 Moroccan honey samples from the Mamora forest region. The samples were directly provided by the beekeepers, all professionals. The quantitative analysis showed that nectar is the main honey source in the samples studied, and that most honeys have a medium-low presence of botanical elements (BEN). The qualitative analysis of the samples showed the presence of 54 taxa belonging to 29 families, and 31 of the samples were unifloral: 24 of eucalyptus, 3 of orange, 2 of Loeflingia, 1 of mint and 1 of Ridolfia segetum. The eucalyptus honeys of the studied region are characterized by their high content in pollen grains (NGP; x¯=180000) and their low honeydew indicator elements content (HDE; x¯=4000); Plantago f. (present in 70% of the samples), Quercus f. and Brassicaceae (50%) and Ceratonia siliqua (30%) could be mentioned among the characteristic accompanying species of this honey type.  相似文献   

13.
The lizard genus Liolaemus is endemic to temperate South America and includes approximately 200 species. Liolaemus koslowskyi occurs in north‐western Argentina, where it is confined to a system of interior basins and valleys. This topographically complex region is now viewed as different enough that it has been suggested for recognition as a separate zoogeographical region: The Monte Desert of Mountains and Isolated Valleys. Here we use the mtDNA cytochrome b sequence data to investigate the phylogeographical pattern of L. koslowskyi and its relationships with other species of the darwinii group. Liolaemus koslowskyi is monophyletic with respect to all the species of the darwinii group included in this analysis. Three main clades were recovered within L. koslowskyi and we hypothesized that at least one of these, which shows 7% genetic divergence, is a candidate species. We discuss the phylogeographical patterns in association with the geological history of the region. The highly structured L. koslowskyi clade suggests that it has a relatively ancient history in a topographically rich, terrestrial archipelago of habitat and tectonic islands that are themselves relictual mountains and valleys.  相似文献   

14.
An overview of the Tipulidae known to occur in northern Morocco with an emphasis on the Rif mountains is given, incorporating new distribution data based on recently collected material in the area. Dolichopeza (Dolichopeza) hispanica, Tipula (Lunatipula) subpustulata, and Tipula (Yamatotipula) afriberia afriberia are recorded for the first time for the Rif. Tipula (L.) stimulosa Mannheims, 1973 and T. (Vestiplex) vaillanti vaillanti Theowald, 1977 are reported for the first time for the Rif and Morocco. Tipula (Lunatipula) pseudocinerascens Strobl, 1906 and Tipula (Savtshenkia) confusa van der Wulp, 1883 are recorded for the first time for the Rif, Morocco and North Africa. A new species of the subgenus Lunatipula, T. (L.) pjotri n. sp., is described and illustrated. Nephrotoma exastigma, previously reported for the Rif, seems to be absent in Morocco. Reports of Tipula (Emodotipula) obscuriventris Strobl, 1900 for Morocco actually refer to T. (E.) leo. This brings the number of Tipulidae for Morocco to 39 species and for the Rif to 28. An updated checklist of the Tipulidae of Morocco is provided.  相似文献   

15.
Investigations were undertaken in an area of western Norway, approximately 30 km from the coast. The area is dominated by Molinia caerulea heaths on gentle slopes of silt-dominated glacial deposits. Pollen analyses were made on 3 soil profiles. Each profile could be divided into 2 local pollen assemblage zones (PAZs) corresponding with a change from dry to damp soils. From a comparison of the fossil pollen assemblages with pollen assemblages from surface samples collected from present-day Molinia heaths, and a radiocarbon date, the Molinia heaths can be shown to have originated about 1900 years BP. The persistence of the Molinia heaths is probably related to the high water-holding capacity of the sediments and the influence of human activity.  相似文献   

16.
Knowledge about vegetation and fire history of the mountains of Northern Sicily is scanty. We analysed five sites to fill this gap and used terrestrial plant macrofossils to establish robust radiocarbon chronologies. Palynological records from Gorgo Tondo, Gorgo Lungo, Marcato Cixé, Urgo Pietra Giordano and Gorgo Pollicino show that under natural or near natural conditions, deciduous forests (Quercus pubescens, Q. cerris, Fraxinus ornus, Ulmus), that included a substantial portion of evergreen broadleaved species (Q. suber, Q. ilex, Hedera helix), prevailed in the upper meso-mediterranean belt. Mesophilous deciduous and evergreen broadleaved trees (Fagus sylvatica, Ilex aquifolium) dominated in the natural or quasi-natural forests of the oro-mediterranean belt. Forests were repeatedly opened for agricultural purposes. Fire activity was closely associated with farming, providing evidence that burning was a primary land use tool since Neolithic times. Land use and fire activity intensified during the Early Neolithic at 5000 bc, at the onset of the Bronze Age at 2500 bc and at the onset of the Iron Age at 800 bc. Our data and previous studies suggest that the large majority of open land communities in Sicily, from the coastal lowlands to the mountain areas below the thorny-cushion Astragalus belt (ca. 1,800 m a.s.l.), would rapidly develop into forests if land use ceased. Mesophilous Fagus-Ilex forests developed under warm mid Holocene conditions and were resilient to the combined impacts of humans and climate. The past ecology suggests a resilience of these summer-drought adapted communities to climate warming of about 2 °C. Hence, they may be particularly suited to provide heat and drought-adapted Fagus sylvatica ecotypes for maintaining drought-sensitive Central European beech forests under global warming conditions.  相似文献   

17.
Total pollen production per inflorescence and per square meter were studied in anemophilous species of the Poaceae family, to determine the relative contribution of each species to the total load of pollen released and to identify the species with the highest potential pollen emission. This was done by calculating the number of pollen grains per flower and per inflorescence and by estimating the density of inflorescences in an area of one square meter. Pollen production per inflorescence varied between 12,000 and 15 million grains, often being higher in the perennial species. Mountainous, grassland, riverside, and littoral areas contributed similarly to the amount of pollen grain production per square meter. Species such as Gaudinia fragilis, Hordeum murinum, Lolium rigidum, and Trisetaria panicea, with high pollen records, were found in all the studied areas. Aerobiological analysis will be undertaken to determine the main pollen season of Poaceae species. The results obtained are of great importance for respiratory health management in this region.  相似文献   

18.
19.
The demographic dynamics of three populations of Dioon edule Lindl. (Zamiaceae) were studied in a fragmented landscape using projection matrix modelling. Compared with other plant species, D. edule behaves like a tree life-form species. Density and spatial distribution patterns varied among populations according to models for animal-dispersed tree species. In all scenarios, λ was most sensitive to changes in abundance of adult plants. The elasticity reproductive component (F) for the three populations was zero and stasis values (L) were higher, this being a function of the permanence of non-reproductive individuals. It was detected that disturbance influences the population dynamics of D. edule as a function of adult plant persistence. This observation suggests that the conservation of adult plants is critical for D. edule and perhaps for all cycads species. Adult plant decapitation should be halted at the 'Monte Oscuro' population, subjected to sustainable management since 1990, if higher seed production is needed in rural nurseries.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 381–391.  相似文献   

20.
Poaceae pollen is one of the most prevalent aeroallergens causing allergenic reactions. The aim of this study was to characterise the grass pollen season in Tetouan during the years 2008–2010, to analyse the effect of some meteorological parameters on the incidence of the airborne Poaceae pollen, and to establish forecasting variables for daily pollen concentrations. Aerobiological sampling was undertaken over three seasons using the volumetric method. The pollen season started in April and showed the highest pollen index in May and June, when the maximum temperature ranged from 23 to 27 °C, respectively. The annual pollen score recorded varied from year to year between 2,588 and 5,404. The main pollen season lasted 114–173 days, with peak days occurring mainly in May; the highest concentration reached 308 pollen grains/m3. Air temperature was the most important meteorological parameter and correlated positively to daily pollen concentration increase. An increase in relative humidity and precipitation was usually related to a decrease in airborne pollen content. External validation of the models performed using data from 2011 showed that Poaceae pollen concentration can be highly predicted (64.2–78.6 %) from the maximum temperature, its mean concentration for the same day in other years, and its concentration recorded on the previous day. Sensitive patients suffering allergy to Poaceae pollen are at moderate to highest risk of manifesting allergic symptoms to grass pollen over 33–42 days. The results obtained provide new information on the quantitative contribution of the Poaceae pollen to the airborne pollen of Tetouan and on its temporal distribution. Airborne pollen can be surveyed and forecast in order to warn the atopic population.  相似文献   

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