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1.
I. Ferrari 《Hydrobiologia》1976,51(3):245-257
The evolution of some limnological parameters during the ice cover period was studied in a mountain lake in the Northern Apennines: Lago Santo Parmense (1507 m a.s.l.; maximum depth 22.5 m). The changes in the biomass and production rate of the phytoplankton were analyzed in relation to the changes in the various physical, chemical and biological parameters (the thickness of the ice cover; the contents of dissolved oxygen, orthophosphate phosphorus, total phosphorus and other nutrients; the zooplankton biomass). The research was carried out in winter 1973 and 1974. A comparison was made with other mountain lakes with morphometric and trophic characteristics similar to those of Lago Santo Parmense.This research was in part supported by a grant (No. 74.00734.04) of Consiglio Nazionale delle Ricerche, ItalyThis research was in part supported by a grant (No. 74.00734.04) of Consiglio Nazionale delle Ricerche, Italy  相似文献   

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Marine crocodylomorphs were particularly abundant in Europe during the Middle Jurassic, but were very scarce in Africa. New finds of thalattosuchian cranial remains in Morocco suggest that this scarcity is probably related to poor sampling rather than original diversity. These remains pertain to the coastal thalattosuchians, the teleosauroids, and particularly to the clade grouping the blunt‐toothed ‘Steneosaurusobtusidens and the genus Machimosaurus. A new tribe is erected grouping these two taxa: Machimosaurini. Until now the machimosaurins have been known from the middle Callovian. The new material extends the presence of this group further back to the lower Bathonian, nearly 5 myr earlier. The machimosaurins are the only teleosauroid group that has been recently reviewed, and the difference between the revised diversity provided herein and that previously reported is large. A review of other teleosauroids and clear establishment of their phylogenetic relationships are also likely to have considerable impact on their observed diversity. So, until a complete review of the teleosauroids is carried out, the results of crocodylomorph diversity analyses should be treated with caution.  相似文献   

4.
This article compliments the S18 session (transmission of traditional ecological knowledge and conservation of medicinal plants) at the 13th International Congress of Ethnobiology (ISE) in Montpellier, France (May 2012). The aim of the article is to provide an insight into the livelihoods of a Berber community, a village of the High Atlas Mountains of Morocco, of the local biodiversity and most importantly, the prevalent use of medicinal plants for primary health care. It seeks to demonstrate the value of traditional ecological and herbal knowledge for the subsistence of the community and emphasises the vital role that family and community connections play for the transmission of traditional herbal knowledge within the community.  相似文献   

5.
This article compliments the S18 session (transmission of traditional ecological knowledge and conservation of medicinal plants) at the 13th International Congress of Ethnobiology (ISE) in Montpellier, France (May 2012). The aim of the article is to provide an insight into the livelihoods of a Berber community, a village of the High Atlas Mountains of Morocco, of the local biodiversity and most importantly, the prevalent use of medicinal plants for primary health care. It seeks to demonstrate the value of traditional ecological and herbal knowledge for the subsistence of the community and emphasises the vital role that family and community connections play for the transmission of traditional herbal knowledge within the community.  相似文献   

6.
《Palaeoworld》2023,32(3):442-457
In the Amellago area (central High Atlas), the widely distributed Toarcian succession consists of marls and marly limestones of the Tagoudite and Agoudim formations. We here describe, for the first time, the ammonites of the Polymorphum Zone from the Tagoudite Formation, including Canavaria cf. rosenbergi Fucini, C. aff. zancleana (Fucini), Dactylioceras (Eodactylites) mirabile (Fucini), D. (E.) aff. mirabile (Fucini), D. (E.) pseudocommune Fucini, D. (E.) simplex (Fucini), D. (Orthodactylites) aff. crosbeyi (Simpson), Lytoceras gr. villae Meneghini, Neolioceratoides cf. hoffmanni (Gemmellaro) and Praepolyplectus sp. This ammonite assemblage is closely correlated with those reported from the Polymorphum Zone of several basins of the Tethyan margins and the Northwest European Subboreal Realm, indicating marine communications between the different Moroccan Jurassic basins and the central Atlantic trough. The overlying Agoudim Formation yields ammonites of the Levisoni Zone in its base and rare ammonites of the Bifrons Zone in the middle part. Four significant changes in the ammonite assemblages during the early-middle Toarcian and their probable causes are also discussed.  相似文献   

7.
This article compliments the S18 session (transmission of traditional ecological knowledge and conservation of medicinal plants) at the 13th International Congress of Ethnobiology (ISE) in Montpellier, France ( May 2012). The aim of the article is to provide an insight into the livelihoods of a Berber community, a village of the High Atlas Mountains of Morocco, of the local biodiversity and most importantly, the prevalent use of medicinal plants for primary health care. It seeks to demonstrate the value of traditional ecological and herbal knowledge for the subsistence of the community and emphasises the vital role that family and community connections play for the transmission of traditional herbal knowledge within the community.  相似文献   

8.
Diverse tetrapod track assemblages with Scoyenia invertebrate traces were discovered in the Triassic Timezgadiouine and Bigoudine formations of the Argana Basin (Western High Atlas, Morocco). The ichnofossils occur in alluvial plain sandstones and mudstones of the Irohalène Member (T5) and Tadart Ouadou Member (T6) considered Carnian-Norian in age by vertebrate remains and palynomorphs. Tetrapod footprints are assigned to Apatopus, Atreipus-Grallator, Eubrontes isp., Parachirotherium, cf. Parachirotherium postchirotherioides, Rhynchosauroides ispp., and Synaptichnium isp. They can be referred to lepidosauromorph/ archosauromorph, basal archosaur, and dinosauromorph trackmakers. Apatopus, represented by 11 tracks of a more than 4 m long trackway, is recorded for the first time outside of North America and Europe. The assemblage concurs with the proposed Late Triassic age of the track-bearing beds by the occurrence of Apatopus, Atreipus-Grallator, and Eubrontes. If this is accepted, the stratigraphic range of Synaptichnium and Parachirotherium, hitherto known only from Early or Middle Triassic deposits, has to be extended to the Carnian-Norian. The occurrence of Eubrontes in the Irohalene Member (T5) provides further evidence for large theropods in pre-Jurassic strata. All assemblages are referred to the Scoyenia ichnofacies indicating continental environments with alternating wet and dry conditions.  相似文献   

9.
This study explores the association between individual beliefs in local Islamic Saints in the High Atlas of Morocco and the use of the environment. This exploration is done within the framework of a traditional institution of natural resource management, based on the regulations (called Agdal) of access to common pastoral resources. Research methods included participant observation and interviews during several stays between 2003 and 2008 among the Amazig (Berber) people of the Mesioua tribe, and a survey of 80 households in the village of Warzazt. Our data show an association between the transformation of traditional individual beliefs in local Saints and new agro-pastoral practices that have previously been linked to the disappearance of Agdal-managed pastures and biodiversity loss. We conclude that, in addition to the more material dimensions of climate change, population increase, migration, or expansion of cash economies, religious beliefs should also be taken into account when analyzing the use of natural resources and agro-pastoral change processes.  相似文献   

10.
Background Phlebotomus (Paraphlebotomus) sergenti is at least one of the confirmed vectors for the transmission of cutaneous leishmaniasis caused by Leishmania tropica and distributed widely in Morocco. This form of leishmaniasis is considered largely as anthroponotic, although dogs were found infected with Leishmania tropica, suggestive of zoonosis in some rural areas.ConclusionOur findings supported the notion that Phlebotomus sergenti is the primary vector of Leishmania tropica in this focus, and that the latter is genetically very heterogeneous. Furthermore, our results might be suggestive of a certain level of heterozygosity in Leishmania tropica population. This finding, as well as the feeding of the vectors on different animals are of interest for further investigation.  相似文献   

11.
An assemblage of abundant and well-preserved tetrapod footprints has been discovered in the Tanamert Member (T3) of the Triassic Timezgadiouine Formation (Argana basin, western High Atlas, Morocco). It is the first fossil record from T3. Surfaces from different localities show a uniform tetrapod ichnofauna that consists of chirotherian and small lacertoid forms. The chirotherians are assigned to the plexus Protochirotherium—Synaptichnium, their trackmakers interpreted as basal archosaurs. The lacertoid imprints show close affinities with Rhynchosauroides and may reflect archosauromorphs or lepidosauromorphs. Protochirotherium—Synaptichnium assemblages are characteristic of the Early Triassic and were known previously only from units of this age in central Europe. Biostratigraphically, the European record implies a wide-spread pre-Anisian Protochirotherium—Synaptichnium dominated assemblage preceding the first appearance of Chirotherium barthii near the Olenekian-Anisian boundary. The stratigraphic position of T3 between Late Permian (uppermost T2) and Middle Triassic (T4) and the European correlatives suggest an Early Triassic age of this unit. It is the first record of Early Triassic continental deposits in Morocco. The surfaces from T3 open up perspectives for further contributions to ecology, biogeography and locomotion of early archosaurs. Furthermore, excellent outcrops and quality of footprint preservation in the Argana basin offer a potential for clarification of ichnotaxonomic and biostratigraphic issues.  相似文献   

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The present study investigates the population trends of Black-necked Grebe Podiceps nigricollis (Podicipedidae: Podicidae) over 5 years (2009–2013) in three Middle Atlas wetlands (Aguelmam Afennourir, Dayet Aoua and Dayet Ifrah). Using generalized linear models with a Poisson distribution, we demonstrated that the number of Black-necked Grebe breeding pairs has varied significantly and positively over the 5 years and between the three study wetlands. The annual population growth rate of the three colonies was 0.48 (±0.01). This positive trend is consistent with the current Least Concern conservation status of the IUCN Red List. Further more detailed studies are, however, needed to improve our understanding on the mechanisms driving the population increase in this part of North Africa. This remains a prerequisite for proper population conservation and management.  相似文献   

14.
Männik, P., Loydell, D.K. & Lubeseder, S. 2010: Sheinwoodian (Silurian) conodonts and graptolites from NE Anti‐Atlas, Morocco. Lethaia, Vol. 44, pp. 410–416. Conodonts and graptolites from a limestone at the base of the Tamaghrout Formation indicate that this is of early Wenlock age. This is the first unequivocal dating of a Sheinwoodian limestone from Morocco. All of the conodonts are known also from several other regions and suggest that there was no major difference in conodont faunas in northern Gondwana, Baltica and Laurentia at this time. Biostratigraphy, conodonts, graptolites, Morocco, Silurian, Sheinwoodian.  相似文献   

15.
The Barbary macaque, Macaca sylvanus is a very adaptable primate species occupying a wide range of habitats in Morocco and Algeria. Several groups of this endangered macaque can be found in tourist sites, where they are affected by the presence of visitors providing food to them. We compare the activity budgets and the diet of semiprovisioned and wild‐feeding groups of Barbary macaques in the central High Atlas Mountains of Morocco from February to August 2008. We used instantaneous scan sampling at 15‐min intervals. The behaviors included in the activity budget were feeding, moving, foraging, resting, and aggressive display. Food items were grouped into seven categories. We found no differences between the two groups in the daily percentages of records attributed to feeding. The semiprovisioned group spent significantly more time engaged in resting and aggressive behavior, and foraged and moved significantly less than the wild‐feeding group. There was no significant difference between the two groups in time spent eating leaves, fruits, or roots and bark. The semiprovisioned group, however, spent significantly less time per day feeding on herbs, seeds, and acorns than the wild‐feeding group. Human food accounted for 26% of the daily feeding records for the semiprovisioned group and 1% for the wild‐feeding group. Our findings agree with previous studies and indicate that in the tourist site, where food is highly clumped, macaques decreased foraging time yet showed higher levels of contest competition. Our results support the common claim that the diet of the Barbary macaque is highly flexible, differing among its varied habitats. Conservation efforts for the Barbary macaques should take into account the changes in behavior that human‐modified environments may cause.  相似文献   

16.
This study describes the dispersal traits and dispersal patterns of 51 perennial plant species belonging to 19 families in an oro-Mediterranean thorn cushion plant formation on the High Atlas, Morocco. Diaspore type, mass, number, antitelechoric mechanisms and dispersal time were studied with respect to growth forms, dispersal modes and spatial dispersal. Species spanned 105 range of diaspore mass, which coincided with those found in other high mountain regions. Diaspore mass was significantly higher in trees and shrubs than in semi-shrubs and perennial herbs. Barochorous and zoochorous species are more likely to have heavy diaspores, whereas anemochorous and ballistic species have a medium diaspore mass and semachorous and ombro-hydrochorous species have low diaspore mass. Diaspore number was significantly higher in trees and shrubs than in semi-shrubs and perennial herbs. The barochorous, ombro-hydrochorous and zoochorous species tended to produce higher diaspore numbers than species with other dispersal modes. Bradyspory was well-developed by trees and large shrubs dispersed by biotic vectors. Synaptospermy was represented by its long dispersal component. Myxospermy was significantly associated with semi-shrubs and perennial herbs with restricted spatial dispersal. It seems that ombro-hydrochory combined with myxospermy and a high number of light seeds is an efficient mechanism that ensures successful establishment of the most typical and endemic thorn cushion plant species, such as Alyssum, Vella and Ormenis. In our study area, the highest dispersal availability was synchronized with the dry summer season (July–August) and the beginning of the rainy months (September). The dispersal peak for the wind-dispersed species, which is the most effective primary dispersal mode, occurs during the dry season, while dispersal for the biotic-dispersed species takes place throughout the year.  相似文献   

17.
Summary The high-plateau of the Jbel Bou Dahar, situated in the Central and Eastern High Atlas of Morocco, represents a Lower Jurassic carbonate platform that drowned at the beginning of the Toarcian. Three phases of platform evolution can be distinguished: During thepre-drowning phase (upper Sinemurian— upper Pliensbachian) the platform interior facies reflects a restricted-marine lagoonal environment, protected by scattered buildups and cemented debris at the platform margin. Upper and mid-slope are dominated by coarse-grained, poorly sorted limestones, deposited through debris flows during sea-level lowstands. Sea-level highstand deposits occur at the toe of slope and are formed by an alternation of fine-grained litho- and bioclastic pack- to grainstones (turbidites), marls and mud- to wackestones (hemipelagic oozes). A condensed section, reflecting an abrupt and fundamental environmental change along the entire platform, characterises thedrowning phase (upper Pliensbachian— lower Toarcian). Within the platform interior densely packed biosparites represent the switch to high-energy environments, causing erosion of the former pre-drowning lagoonal sediments. These erosional products were redeposited on the platform slope, leading to the formation of coarse-grained non-skeletal sparites and micrites. Both platform interior and slope successions show a series of cyclic variations in sediment composition that could have been triggered by small-scale sea-level fluctuations. In contrast to the abrupt facies change at the pre-drowning —drowning boundary, the transition to thepost-drowning phase (lower Toarcian—Aalenian) is gradual. During this phase, biopelmicrites and pure micrites were deposited in all platform sections, followed by the deposition of calcistiltites. The facies point to quiet-water conditions below storm-wave base and display a uniform deep-marine sedimentation. This analysis shows that the drowning of the Jbel Bou Dahar carbonate platform was caused by abrupt and fundamental changes in the shallow-water realm. After exposure of the platform, these changes prevented the carbonate factory from re-establishing itself and made it impossible for the platform to keep up with the subsequent rise in sea level. These local changes were probably triggered by high-frequency sealevel variations in combination with regional or even worldwide changes in ocean circulation patterns.  相似文献   

18.
The characteristic feature of the physical structure of Lac Pavin is a distinct and permanent chemically induced density increase between about 60 and 70 m depth. This chemocline separates the seasonally mixed mixolimnion from the monimolimnion, which is characterized by elevated temperature and salinity as well as complete anoxia. Previously published box-models of the lake postulated substantial groundwater input at the lake bottom, and consequently a short water residence time in the monimolimnion and high fluxes of dissolved constituents across the chemocline. We present a new view of the physical structure and dynamics of Lac Pavin, which is based on the results of high-resolution CTD profiles, transient and geochemical tracers (tritium, CFCs, helium), and numerical modeling. The CTD profiles indicate the existence of a sublacustrine spring above rather than below the chemocline. A stability analysis of the water column suggests that vertical turbulent mixing in the chemocline is very weak. A numerical one-dimensional lake model is used to reconstruct the evolution of transient tracer distributions over the past 50 years. Model parameters such as vertical diffusivity and size of sublacustrine springs are constrained by comparison with observed tracer data. Whereas the presence of a significant water input to the monimolimnion can clearly be excluded, the input to the mixolimnion – both at the surface and from the indicated sublacustrine spring – cannot be accurately determined. The vertical turbulent diffusivity in the chemocline is well constrained to K 5×10-8 m2 s-1, about a factor of three below the molecular diffusivity for heat. Assuming thus purely molecular heat transport, the heat flow through the chemocline can be estimated to between 30 and 40 mW m-2. With respect to dissolved constituents, the very weak turbulent diffusive exchange is equivalent to a stagnant monimolimnion with a residence time of nearly 100 years. Based on these results and vertical concentration profiles of dissolved species, diffusive fluxes between monimolimnion and mixolimnion can be calculated. A large excess of helium with a 3He/4He ratio of (9.09 ± 0.01)×10-6 (6.57 R a) is present in the monimolimnion, clearly indicating a flux of magmatic gases into the monimolimnion. We calculate a flux of 1.0×10-12 mol m-2 s-1 for mantle helium and infer a flux of 1.2×10-7 mol m-2 s-1 (72 t year-1) for magmatic CO2. The monimolimnion appears to be in steady state with respect to these fluxes.  相似文献   

19.
In this study we describe how the river morphology of seven High Tatras streams has been influenced in different ways by a severe windstorm that occurred in November 2004. A control site situated in an undisturbed area is compared with six sites in windstorm damaged areas. In 2009–2010 River Habitat Survey (RHS) was used to assess the character of 500 m lengths of stream and to derive associated morphological indices (HQA, HMS sensu Raven 1998, RHS indices sensu Vaughan 2010). Large amounts of large woody debris in the channel influenced the streams despite most of it having been removed after the windstorm. Streams situated in deforested valley slopes were probably more affected by erosion; they had higher amounts of transported inorganic matter and also depositional bar features. Some changes in land-use had occurred with streams situated on the south-east side of the High Tatras having a more uniform banktop vegetation structure than the other streams. Distinct secondary succession of bank top vegetation was observed along windstorm influenced streams. The highest percentage of shrubs occurred where impacted streams remained untouched. Morphologically, the streams most affected by windstorm are those situated in deforested steep valley slopes that are affected by erosion and siltation.  相似文献   

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