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1.
《Journal of bryology》2013,35(3):339-342
Abstract

Photosynthesis, respiration, net assimilation, chlorophyll b concentration, and levels of potassium, calcium, magnesium and iron were measured in 2 cm shoot segments of Pleurozium schreberi in order to examine patterns of physiological decline with ageing in a continuously growing species. Photosynthesis and chlorophyll b levels declined rapidly after the apical shoot segment and were undetectable after a distance of 8 cm from the shoot apex. Respiration rate also fell rapidly at first but then declined more gradually and some respiration was detected in all shoot segment samples. Potassium and magnesium levels declined approximately linearly in relation to segment number. Calcium levels, expressed on a concentration per unit weight basis, became progressively higher in older segments but the calcium content per segment may actually decline with age. The disparity may be due to a decline in the proportion of cytoplasm compared with cell wall material in older segments.

No clear division could be made between living and dead shoot segments. Different physiological processes decline at different rates as ageing occurs and the importance of the age structure of shoot samples is discussed in relation to design of physiological experiments.  相似文献   

2.
The Keota site, in the Middle Pennsylvanian (Desmoinesian) Keota Sandstone Member, McAlester Formation (Krebs Group) of Haskell County, Oklahoma, yields an extensive ichnofossil assemblage of arthropod trackways, insect resting traces, arthropod feeding and grazing traces, fish swimming traces, and tetrapod footprints. This ichnofossil assemblage occurs in a 0.8 to 1.5-m-thick unit of thinly laminated and ripple-laminated sandstone at the base of the Keota Sandstone Member that is interpreted as a tidal flat sandstone. The arthropod traces are assigned to the ichnotaxa Diplichnites gouldi Gevers types A and B, Diplopodichnus biformis Brady, Paleohelcura tridactyla Gilmore, Tonganoxichnus buildexensis Mángano, Buatois, Maples and Lanier, Gordia marina Emmons, cf. Cochlichnus sp. and Treptichnus bifurcus Miller. The fish swimming traces are assigned to Undichna britannica Higgs, and the tetrapod tracks to Notalacerta ichnosp. and Pseudobradypus ichnosp. The Keota ichnofossil assemblage thus documents the first North American Pennsylvanian record of Paleohelcura tridactyla and the first record of Pseudobradypus from the western United States. This ichnofossil assemblage also provides compelling evidence of a freshwater habitat in a tidal flat setting during deposition of the fossil-bearing sandstone at the Keota site. Indeed, the Keota ichnofossil assemblage is characteristic of a Carboniferous-Permian Tonganoxichnus assemblage that identifies nonmarine tidal flat settings.  相似文献   

3.
A new genus of Violaceae is described from Brazil.Hybanthopsis Paula-Souza, with a single species (H. bahiensis Paula-Souza), is endemic to caatingas of Bahia, Brazil, and is morphologically most similar toHybanthus, from which it differs by the fruit morphology and especially its peculiar seeds.
Um novo gênero brasileiro de Violaceae é descrito.Hybanthopsis Paula-Souza, com uma única espécie (H. bahiensis Paula-Souza), é endêmico de caatingas do Estado da Bahia, e é morfologicamente mais similar aHybanthus, do qual difere pela morfologia do fruto e especialmente por suas sementes peculiares.
  相似文献   

4.
5.
Abstract

After the successful establishment of free–living populations of Rose–ringed Parakeets (Psittacula krameri) and Common Mynas (Acridotheres tristis) in Jeddah, an overview of all exotic birds imported into Jeddah in the first three months of 1990 is given.  相似文献   

6.
Abstract

The present distribution of the Black Francolin (Francolinus francolinus) in Cyprus is concentrated in two restricted areas: the Karpasia peninsula in the north-east of the island, where about 200 birds live; and the lowlands of Paphos district in the west of Cyprus, where about 150 birds occur mainly on Akamas peninsula and around the villages of Paphos and Polis. As the decline of the population is correlated with the level of hunting, protection is urgently needed.  相似文献   

7.
A list of 285 species of Sarcophagidaе in the Middle East countries is presented with distributional data, including Bahrain (3 species), Cyprus (46), Egypt (both African and Asian parts) (114), Iran (83), Iraq (17), Israel (113), Jordan (14), Kuwait (3), Lebanon (13), Oman (2), Gaza Strip (5), Palestinian Authority (42), Quatar (1), Saudi Arabia (37), Syria (42), Turkey (both European and Asian parts) (157), United Arab Emirates (14) and Yemen (15). Three new synonyms are established: Blaesoxipha delilah Lehrer, 2006 = Agriella setosa Salem, 1938, syn. n.; Blaesoxipha nahaliana Lehrer, 2008 = Blaesoxipha popovi Rohdendorf, 1937, syn. n.; and Liosarcophaga daccanella Lehrer, 2008 = Liosarcophaga (s. str.) dux (Thomson, 1869), syn. n. Four new combinations for species names are proposed: Liopygia (Engelisca) adhamae (Lehrer & Abou-Ziad, 2008), comb. n.; Liosarcophaga (s. str.) pedestris (Villeneuve, 1910), comb. n.; Liosarcophaga (Pandelleisca) theodori (Lehrer, 1998), comb. n., and Liosarcophaga (Pharaonops) tewfiki (Salem, 1940), comb. n.  相似文献   

8.
Summary  The Tailfer section (Belgium, northern border of the Dinant Synclinorium) exposes Middle Frasnian shallow-water limestones. This paper proposes a sedimentological analysis based on classical petrology, which leads to the identification of 19 fourth order sequences, forming three third order system tracts. This sedimentological analyses is complemented by carbon isotopic and magnetic susceptibility (MS) data (based on the relation between MS and lithogenic input). Each system tracts is characterised by a particular evolution of the isotope and MS curve:
–  --Biostromal Unit: the biostromes are built by lamellar and branching stromatoporoids and massive metazoans. MS values are weak, in relation with the important distance from landmasses and lesser amounts of lithogenic contribution. The carbon isotope values are close to Frasnian seawater values.
–  --Lagoonal Unit: it corresponds to a lagoonal facies succession, from inter- to supratidal zones, rich inAmphipora, paleosiphonocladalesUmbella, and pellets, alternating with paleosoils. MS values are high, related to landmass proximity and high lithogenic input. The carbon isotopic curve shows strongly negative values, close to −7%., resulting probably from a continental influence.
–  --Lagoonal and biostromal Unit: it consists of a lagoonal succession with some biostromal interruptions. MS values are lower than in the lagoonal unit and the isotopic values are higher (close to 0%.), related to an increase in distality.
  相似文献   

9.
Michael Schlirf 《Ichnos》2013,20(4):249-254

The study of Jurassic Zoophycos from south‐eastern France has led us to some original results concerning its morphological organization and paleoenvironmental significance. Zoophycos represents a spreite constituted by a coiling lamina, constructed upwards in sediments, with only one opening at the sediment‐water interface. Zoophycos, produced by a deep sediment feeder, is emplaced late in an almost coherent substrate, intermediate between soft and firm ground. This suggests periods of very low or no sedimentation during which time the trace was constructed.

The Zoophycos studied developed on slope areas, characterized by a particular style of sedimentation: periods of nutrient supplies coming from proximal areas, alternating with periods of sedimentary breaks. Other paleoecologic and paleoethologic characteristics of the Zoophycos‐producer are discussed here: working activity, competition behavior, substrate modification, growing pattern and burrow oxygenation are the most interesting.  相似文献   

10.
The oldest fossil Diptera are known from the Grès à Voltzia Formation (Upper Buntsandstein) of the northern Vosges Mountains (northeastern France), the age of which is early Anisian (early Middle Triassic). Six monotypic genera assigned to all the major lineages of Diptera (except for the Culicomorpha) were described from these beds based on adults (Krzeminski et al. 1994; Krzeminski & Krzeminska 2003). Immature Diptera also occur in the Grès à Voltzia (ca 30 specimens). Pupae are abundant whereas the larvae are extremely rare. The most numerous and well-preserved pupal type has been assigned to Voltziapupa n. gen. (V. tentata n. sp. and V. cornuta n. sp.). These pupae display plesiomorphic characters combined with possibly derived ones. Among the larvae, Anisinodus crinitus n. gen., n. sp. shows culicomorph features. It represents the earliest Culicomorpha (Chironomoidea inc. fam.) known up to date. The other types of dipteran immatures (six pupal and two larval ones) occurring in the Grès à Voltzia are less well preserved, so that their systematic position is difficult to determine and they have been assigned to the Nematocera incertae sedis. These immature Diptera are the first ones recorded from the Triassic.  相似文献   

11.
The results of the first detailed screening of a resistance to Bremia lactucae in naturally growing populations of Lactuca saligna are presented here. In total, 146 accessions from 25 populations of L. saligna originating in Israel (N = 136), France (N = 8), Jordan (N = 1) and Turkey (N = 1) were tested at seedling stage for their resistance to 10 highly virulent isolates (races) of B. lactucae from Lactuca sativa (DEG2, Bl:5, Bl:15, Bl:16, Bl:17, Bl:18, Bl:21, Bl:22, Bl:24 and Bl:25). Our study strongly supports the suggestion that L. saligna is indeed generally highly resistant to B. lactucae. However, our results provide evidence that at least at a seedling stage L. saligna may not be a non‐host plant for B. lactucae, as was hypothesised for approximately the last 30 years. Some accessions expressed a differential (i.e. race‐specific) response, which accords with other recently published data for this Lactuca species. Furthermore, some geographical differences in race‐specific resistance were observed, too. Tests performed at an adult‐plant stage, however, did not prove race‐specificity of the respective accessions. To summarise, what is behind the race‐specific character of the responses observed at a seedling stage is still uncertain, as is its comparability with the race‐specific resistance of some other Lactuca species such as L. sativa or L. serriola. The presence of plant stage‐dependent resistance, governed by a combined effect of different quantitative trait loci in young and adult plants of L. saligna, is discussed.  相似文献   

12.
Hedychrum zenobia sp. n. is described from Syria and Iraq, and H. linsenmaieri sp. n. from Pakistan. They belong to the H. cirtanum species group hereby established, which includes some of the largest Palaearctic Hedychrum species, characterised by a modified metascutellum projecting over the propodeum, a deep mid-tibial groove in the male and an apicomedial tooth on the third metasomal sternum in the female. Hedychrum cirtanum var. minusculum du Buysson, 1898 is transferred to the genus Hedychridium Abeille de Perrin, 1878 and elevated to species rank as Hedychridium minusculum (du Buysson, 1898) stat. n.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:DE7B4BF7-3E4B-4664-8F3A-1FD480F72A41  相似文献   


13.
Abstract  The Lower Palaeozoic biostratigraphic records in the Alps are briefly reviewed and the result of a new study of the acritarch assemblage found by Sassi et al. (1984) in the greenschist facies black metapelites of the Southalpine metamorphic basement at Col di Foglia, and studied by Kalvacheva et al. (1986), is presented. The new  taxonomic and biostratigraphic study indicates a late Cambrian age, which is the oldest unquestionable, recently assessed, biostratigraphic dating of the entire Alps, as well as of the Italian peninsular. Keywords Alps, Southalpine metamorphic basement, Eastern Alps, Agordo, Acritarchs, Cambrian Subject codes: G17002  相似文献   

14.
Summary

Based on a revision of large recent collections housed at the Natural History Museum (London), Tel Aviv University and in the private collection of Yu. Verves and L. Khrokalo (Kyiv, Ukraine), new distributional data and an updated list with comments of 28 species of Middle Eastern Sarcophagidae of the subtribe Pterellina are presented. Seventeen of them are recorded for Israel, 11 for Egypt, four for Iran, two each for the Palestinian Authority, Saudi Arabia and Turkey, and one each for Jordan and the UAE. No data are known for the territories of Bahrain, Cyprus, Iraq, Kuwait, Lebanon, Oman, Qatar, Syria and Yemen. Twelve species new to science are described, including nine from Israel (Chaetapodacra montana n. sp., Eremasiomyia bicolor n. sp., E. deserta n. sp., E. fuscata n. sp., Protomiltogramma bidentata n. sp., P. serrata n. sp., Pterella hermonica n. sp., P. indigens n. sp., P. zefatica n. sp.), two from Egypt (Chaetapodacra griseola n. sp., Eremasiomyia alba n. sp.) and one from Saudi Arabia (Protomiltogramma arabica n. sp.). The male of Eremasiomyia nigra Rohdendorf, 1935 is described for the first time. One new combination of specific name is proposed ? Protomiltogramma immunita (Villeneuve, 1923), n. comb. Original keys for the identification of genera and species are proposed. An annotated list of all world genera and species and compiled data on larval habits of Pterellina are included.  相似文献   

15.
Abstract

The variation of 21 morphological parameters was investigated in populations of Atyaephyra desmaresti desmaresti and A. desmaresti orientalis in order to find differences between the sexes and to assess the degree of infraspecific variation. Differences between the sexes were found in three proportional characters of A. desmaresti desmaresti and in five characters of A. desmaresti orientalis. Also, the difference in one meristic character was found to be significant in both subspecies.  相似文献   

16.
《Plant Ecology & Diversity》2013,6(3-4):467-474
Background: Propagule production and dispersal largely determine the distribution and potential migration ability of alpine plant species. Variation in reproductive success caused by year-to-year variation in climate may critically influence these processes.

Aims: To obtain estimates for the propagule rain in high-alpine plant communities and detect potential dispersal events from lower elevations.

Methods: The magnitude and composition of the propagule rain was studied in different plant communities along an elevation gradient from the upper alpine to subnival zone. Propagules were trapped at eight elevations from 2760 to 3070 m a.s.l. for three years from July to September 2003–2005. Vascular plant species and their cover were recorded in an area with a radius of 10 m surrounding the traps.

Results: A five- to 10-fold higher propagule rain was observed in 2003, a year with an exceptionally hot summer, compared to 2004 and 2005. Propagule and species numbers varied highly among years and community types. Few propagules of non-local origin were recorded in any year.

Conclusions: Extremely hot summers are likely to greatly magnify the propagule rain size of species in alpine habitats. Such ‘mast years’ may contribute to enhanced and accelerated vegetation changes in alpine habitats in the absence of limiting factors.  相似文献   

17.

Casts of the foraging tunnels of eastern American moles ( Scalopus aquaticus ) show impressions from the moles' mani along the lateral walls. The number of discernable impressions ranges from one to five, each showing two or three long, flat, blunt-ended claws. The size and shape of the impressions matches the claws on the paddle-like manus of S. aquaticus . The impressions are spaced at regular intervals of about two cm, and probably represent points at which the mole pushed off from the tunnel wall with alternating laterad digging strokes. Tunnel width generally exceeds height by about 15%, reflecting the laterally compressed body of the mole. These tunnel casts help show that clear, recognizable traces can be preserved in loose, humic soils, and demonstrate the type of traces left by a “lateral-thrust” digger with fully sprawled stance, such as S. aquaticus . Identification of traces on the tunnels of living moles may be applied to the fossil record, in which fossilized burrows with similar marks could be attributed to extinct burrowing moles or mole-like locomotion.  相似文献   

18.
Samples of a carbonated orange drink, raw materials, and intermediate products originating from 6 Iraqi bottling plants were examined. 69 drinks, 4 flavoured syrups and 19 simple syrups contained yeasts, whereas all samples from one plant and all samples of beverage base were free from viable yeasts. From the orange drink 2 species were isolated viz. Saccharomyces montanus and Torulopsis stellata. The following species were present in simple syrup: Hansenula anomala, Sacch. bisporus var. mellis, T. candida and T. stellata. Sacch. bisporus var. mellis was also isolated from flavoured syrup. Representative strains were submitted to routine growth tests at reduced oxygen tension, at reduced water activity and on solid soft-drink media containing various amounts of anti-microbially active benzoic acid at pH 3.0. The results are discussed and compared to those obtained in European soft drinks.  相似文献   

19.
A. Dyrcz  H. Nagata 《Bird Study》2013,60(2):166-171
CapsuleTwo populations of the Eastern Great Reed Warblers, one close to settlements and one far away, differed mainly in nest losses which were higher at the latter site.

Aims To compare the breeding ecology of two Japanese populations, and with breeding data from Polish sites.

Methods We studied two sites in 1996. The Seimei site comprises a natural reed-bed (Phragmites australis) (2.0 ha) c. 2 km from residential areas. The Sakura site occurs as smaller reed-bed (0.8 ha) close to residential areas. Field study comprised mainly nest searching and nest monitoring.

Results Breeding density, nest height, number of stems supporting nest, clutch size and brood size were not significantly different between sites. The proportion of nests built on reed stems standing in the water (60%) was significantly higher at the Seimei site (P < 0.001), and the warblers in this habitat experienced significantly higher nesting failure (P < 0.05). Predation was a principal cause of failure at both sites. Significantly more nests suffered from predation at Seimei (53%) than at Sakura (16%). Breeding density was higher at both sites compared with European populations but it fell within ranges of other Japanese populations. Mean first-egg date of first brood does not differ between our sites and Polish ones.

Conclusion The differences between the two Japanese populations and between Japanese and Polish populations were relatively small and were seen mainly in nest losses, breeding density and proportion of nests built over water.  相似文献   

20.
Abstract

Additional new records and references from the literature are given for the Ring-nek-ked Parakeet, Psittacula krameri, in Egypt, Jordan, Israel and Syria. The species only succeeds in surviving in areas where there is little pressure from hunting, for example the city area of Cairo and several localities in Israel.  相似文献   

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