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1.
A survey of trace element contents in fish muscle and liver was performed in different lakes of two northern Patagonian national parks: Nahuel Huapi and Los Alerces national parks. The aim of the work was to obtain the first set of reference data on elements that are not liable to be disturbed by human activities and to identify compositional patterns related to the species and site of collection. The species studied are native creole perch and velvet catfish and exotic brown trout, rainbow trout, and brook trout. The elements analyzed are Br, Cs, Fe, Rb, Se, Na, and Zn. Trace elements in muscle of brown trout, rainbow trout, and creole perch showed statistical patterns that allow one to identify the national park of origin, as well as which of the lakes (Traful, Espejo Chico, or the Nahuel Huapi-Moreno system) of the Nahuel Huapi National Park from which they come. Contents in the liver provide similar but less clear patterns than contents in muscle; however, in some particular cases, they provide additional information. Trace element contents in muscle are also good indicators of the species collected within a lake.  相似文献   

2.
Despite the numerous studies proposing early human population expansions from Africa into Arabia during the Late Pleistocene, no archaeological sites have yet been discovered in Arabia that resemble a specific African industry, which would indicate demographic exchange across the Red Sea. Here we report the discovery of a buried site and more than 100 new surface scatters in the Dhofar region of Oman belonging to a regionally-specific African lithic industry--the late Nubian Complex--known previously only from the northeast and Horn of Africa during Marine Isotope Stage 5, ~128,000 to 74,000 years ago. Two optically stimulated luminescence age estimates from the open-air site of Aybut Al Auwal in Oman place the Arabian Nubian Complex at ~106,000 years ago, providing archaeological evidence for the presence of a distinct northeast African Middle Stone Age technocomplex in southern Arabia sometime in the first half of Marine Isotope Stage 5.  相似文献   

3.
Climate change is affecting the phenology of seasonal events in Europe and the Northern Hemisphere, as shown by several studies of birds’ timing of migration and reproduction. Here, we analyse the long-term (1982–2006) trends of first arrival dates of four long-distance migratory birds [swift (Apus apus), nightingale (Luscinia megarhynchos), barn swallow (Hirundo rustica), and house martin (Delichon urbicum)] and first egg laying dates of two migrant (swift, barn swallow) and two resident species [starling (Sturnus vulgaris), Italian sparrow (Passer italiae)] at a study site in northern Italy. We also addressed the effects of local weather (temperature and precipitation) and a climate index (the North Atlantic Oscillation, NAO) on the interannual variability of phenological events. We found that the swift and the barn swallow significantly advanced both arrival and laying dates, whereas all other species did not show any significant temporal trend in either arrival or laying date. The earlier arrival of swifts was explained by increasing local temperatures in April, whereas this was not the case for arrival dates of swallows and first egg laying dates of both species. In addition, arrival dates of house martins were earlier following high NAO winters, while nightingale arrival was earlier when local spring rainfall was greater. Finally, Italian sparrow onset of reproduction was anticipated by greater spring rainfall, but delayed by high spring NAO anomalies, and swift’s onset of reproduction was anticipated by abundant rainfall prior to reproduction. There were no significant temporal trends in the interval between onset of laying and arrival in either the swift or the barn swallow. Our findings therefore indicate that birds may show idiosyncratic responses to climate variability at different spatial scales, though some species may be adjusting their calendar to rapidly changing climatic conditions.  相似文献   

4.
The timing and synchrony of births of roe deerCapreolus capreolus Linnaeus, 1758 population were examined for 7 consecutive years in northern Italy. From 1997 to 2003, 136 fawns, 65 females and 71 males, from 117 litters were captured. The average date of fawning (30th of May) was constant among years and between sexes. The onset of parturition was 19th of May while the total length of the parturition season was 25 days (from 19th of May to 13th of June). Births were highly synchronous, with 80% of births occurring in 17 days. Synchrony of birth did not exhibit any significant interannual or intersexual variation. The stability of the birth pattern was confirmed by the parturition date of 13 radiocollared females who all gave birth within 4 days in consecutive fawning seasons. In agreement with previous findings, our data support the hypothesis that the roe deer is constrained at both ends of the fawning season by the short time between the fawning season and rut and by the need to match optimal climate conditions and forage quality to face late gestation and lactation. All these factors result in a relatively stable and synchronous birth season.  相似文献   

5.
During the late Bronze age, settlements in Languedoc, southern France, were located on the shore of lagoons lining the Mediterranean, while, in the hinterland, settlements were mainly in the form of villages or cave sites. Information on food plants has been restricted, until now, to sites in the hinterland. In this paper, the archaeobotanical results obtained from two lagoon-shore settlements, La Fangade at Sète, and Portal Vielh at Vendres, are reported. The former provides the first waterlogged assemblage for this period in the French Mediterranean while the latter consists of a dry settlement. Emmer and hulled, six row barley are the most common cereals occurring at the two sites. Other cereals are less frequent, although einkorn chaff is common at La Fangade. Flax, and especially opium poppy, are well represented while faba bean is the only pulse of some importance. Many wild fruits were gathered, especially acorns. Comparison with data from the hinterland suggests that the main difference lay in the cultivation of opium poppy and flax in the lagoon sites. However, may be largely an impression, resulting from the differences in manner of preservation at hinterland and lagoon sites. Local production as distinct from importation of crops is considered and the conclusion is drawn that, at least at La Fangade, hulled barley was grown locally. The arable weed flora indicates that sowing took place during both autumn and spring at La Fangade.  相似文献   

6.
7.
A highly sensitive, simple and rapid spectrofluorimetric method was developed for the determination of amisulpride (AMS) and bumidazone (BUM) in tablet form. The proposed method is based on measuring the native fluorescence of the studied drugs in methanol at 360 and 344 nm after excitation at 276 and 232 nm for AMS and BUM, respectively. The fluorescence–concentration plots were rectilinear over the ranges of 5.0–60.0 ng/mL for AMS and 0.5–5.0 µg/mL for BUM. The lower detection limits were 0.70 ng/mL and 0.06 µg/mL, and the lower quantification limits were 2.0 ng/mL and 0.18 µg/mL for AMS and BUM, respectively. The method was successfully applied for the analysis of AMS and BUM in commercial tablets. Statistical evaluation and comparison of the data obtained using the proposed and comparison methods revealed good accuracy and precision for the proposed method. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

8.
9.
Several ancient olive plants with different genetic, agronomic and morphological characteristics are widespread in the Emilia-Romagna region. In this study, details of 206 trees located in four provinces were collected and their phytometric traits were recorded. Easily recognizable varieties were identified, while plants of uncertain genetic identity were submitted for molecular analysis with SSR markers and compared with cultivars widespread in central Italy and Emilia-Romagna. The genetic analyses showed that most of the ancient olive trees belonged to 10 cultivars that are already characterized, with different cases of intra-varietal clones. The remaining accessions belonged to 19 different genotypes of unknown origin. The highest percentage of policormic trees was found in the Bologna and Rimini provinces. A high percentage of plants located under unfavourable aspects (west to east) was found only in the Rimini territory, which presents peculiar and milder climatic conditions compared to the other provinces. Slope appeared not to be a limiting factor for tree survival. The information obtained could help the rational reintroduction of olive growing in suitable areas of Emilia-Romagna, with the subsequent economic advantages, erosion preservation and germplasm enrichment.  相似文献   

10.
The contribution of applied microbiology and biotechnology for the preservation and restoration of culturally relevant stoneworks has been used only to a minor extent. Until recently it only involved the identification of the living organisms accountable for the deterioration of those materials by classic phenotypic identification methods. This seems to be changing, given the amount of work recently published that focuses in the introduction of molecular-based techniques for the detection of microorganisms in historic stone. Such techniques complement and expand the information up till now gathered by conventional identification methods. Along with this, efforts are being made to develop and implement bio-based methodologies that may actively contribute to the bioremediation of weathered historic stoneworks. The present mini-review aims to provide an overview of recent findings on these matters.  相似文献   

11.
12.
Rift Valley sites in southern Ethiopia and northern Kenya preserve the oldest fossil remains attributed to Homo sapiens and the earliest archaeological sites attributed to the Middle Stone Age (MSA). New localities from the Kapedo Tuffs augment the sparse sample of MSA sites from the northern Kenya Rift. Tephrostratigraphic correlation with dated pyroclastic deposits from the adjacent volcano Silali suggests an age range of 135-123 ka for archaeological sites of the Kapedo Tuffs. Comparisons of the Kapedo Tuffs archaeological assemblages with those from the adjacent Turkana and Baringo basins show broad lithic technological similarity but reveal that stone raw material availability is a key factor in explaining typologically defined archaeological variability within this region. Spatially and temporally resolved comparisons such as this provide the best means to link the biological and behavioral variation manifest in the record of early Homo sapiens.  相似文献   

13.
Abstract. In this paper we present an application of aerial remote sensing to the analysis of spatial information in a mountainous area of central Italy by applying texture measures and landscape indices. Land cover data acquired in different time periods are used to calculate measures of landscape pattern and structure at pixel level (tone and texture variables) and patch‐level (landscape indices). Images of the patches from the 1950s, 1980s and 1990s have been derived from the tone‐texture classification of scanned black‐and‐white photographs. Multitemporal analysis of landscape indices has been performed to detect changes of landscape elements and related effects on vegetation dynamics due to the reduction of human impact.  相似文献   

14.
PCR assays were compared with standard microbiological methods for rapid detection of the United States Pharmacopoeia (USP) bacterial indicators in artificially contaminated samples of raw materials and cosmetic/pharmaceutical products. DNA primers containing the specific sequences of the uidA gene of the β-glucuronidase enzyme for Escherichia coli, the membrane lipoprotein gene oprL for Pseudomonas aeruginosa, and the 16S ribosomal gene for Staphylococcus aureus were used for detection in the PCR reaction. Contaminated samples were incubated for 24 h at 35°C. After incubation in broth media with and without 4% Tween 20, samples were streaked on selective growth media. After 5–6 days, all microbial indicators were morphologically and biochemically identified using standard methods while detection and identification by the PCR-based assays was completed within 27–30 h. Rapid PCR detection of E. coli, S. aureus, and P. aeruginosa will allow a faster quality evaluation and release of raw materials and cosmetic/pharmaceutical products sensitive to microbial contamination. Received 21 June 1998/ Accepted in revised form 11 January 1999  相似文献   

15.
Ciliate protozoans were collected from five watercourses belonging to the hydrographic network of the North Apennines (Italy) and flowing into the middle lower section of the river Po from its right bank. Thirteen stations were selected in the meta- and hyporhithron section of the five studied rivers and samples from water–sediment interface were collected during a 1year period. A total of 175 species of ciliates belonging to 97 genera were found, of which 68 were bacterivorous, 58 were algivorous, 26 were omnivorous and 23 were carnivorous. Their distribution varied both with distance along the river and with the time. Community structures were analysed using some statistical methods and this allowed the determination of similarities among stations and relationships between species and stations. The saprobic index and valency methods were used to evaluate the water quality at the 13 stations. Comparisons between the five watercourses indicate that trophic state influences the composition of ciliate communities. The high similarity observed in the unpolluted stations enabled us to define the typical species and the community of the meta- hyporhithron zone. Conversely, polluted stations showed the lowest similarities. Our results confirm that in watercourses the organic load may be the dominating factor able to influence, if not eliminate the diversifying effects of other factors such as those which characterize the longitudinal zonation of the watercourses.  相似文献   

16.
Saproxylic beetles may act as bio-indicators of high-quality mature woodlands, and their conservation is strongly linked to the quality and quantity of deadwood in a biotope. We tested the effect of deadwood accumulation and habitat variables on saproxylic species richness by investigating six sampling sites under different deadwood management practices that belong to both alluvial and riparian mixed forests of the Po plain, Italy. We sampled 43 obligate saproxylic species. The main factor predicting saproxylic species richness was the amount of deadwood measured by both log diameter and volume. We found a threshold of 0.22 m diameter (confidence interval CI 0.18–0.37 m) and 32.04 m3/ha volume (CI 16.09–64.09 m3/ha) below which saproxylic beetle richness would be significantly reduced and a threshold of 35 m3/ha dead wood volume (CI 33–40 m3/ha) over which species richness increases by <5 %. The other deadwood and environmental components influenced saproxylic beetle richness to a lesser extent; some of them, however, should still be considered for proper management. Forest structure variables describing forest density such as large trees and basal areas have a negative effect on species richness. According to the results of our study, stumps and advanced decaying class are positively correlated, while small logs are negatively correlated to species richness. Thus, in extensively managed forests, the regular cutting of trees should be implemented to create artificial stumps, in order to assure a continuity of deadwood and, in the meantime, increase the number and width of openings in the forest. Moreover, prolonging rotation times can assure the presence of deadwood at intermediate/later stages of decay.  相似文献   

17.
Determination of age and growth in stream fishes of northern Borneo   总被引:1,自引:0,他引:1  
Synopsis In mildly seasonal tropical climates, the pattern of marks on hard body parts of fishes may be difficult to interpret and unreliable for age determination. Many tropical fishes are now known to have annual peaks in spawning activity which are reflected in their length-frequency distributions. Although scales from freshwater stream fishes in the Baram River system of Sarawak, Malaysia revealed no clearly discernable pattern of annual marks, age classes could be identified from the length-frequency histograms with sufficient accuracy for production to be calculated. For management of the numerous and relatively unknown species present in rapidly developing tropical fisheries, serial quantitative samples at the same localities and inter-locality comparisons of length-frequency histograms may offer a fast and effective method of establishing the necessary age structures.  相似文献   

18.
The aim of this study was to identify plant species among the diverse flora of the caatinga ecosystem that are used therapeutically. Research was undertaken in the municipalities of Piranhas and Delmiro Gouveia, in the Xingó region (state of Alagoas, NE Brazil). In order to identify the medicinal plants used in this region, semi-structured questionnaires were applied. The species cited were collected and sent to the Xingó Herbarium for taxonomic analysis. The relative importance (RI) of each species cited was calculated to verify their cultural importance. The therapeutic indications attributed to the species were classified under 16 body systems. A total of 187 medicinal species were cited, from 64 families and 128 genera. The main indications for medicinal plant use were against common colds, bronchitis, cardiovascular problems, kidney problems, inflammations in general, and as tranquilizers. Approximately 16% (30 plant species) were versatile in relation to their use, with an Relative Importance value over 1, having been indicated for up to nine body systems. The body systems that stood out the most were: the respiratory system, the gastrointestinal system, and infectious diseases. Most cited plant parts used for medicinal purposes were flowers, leaves, and inner stem bark.  相似文献   

19.
Rottini Sandrini  L.  Avian  M. 《Hydrobiologia》1991,216(1):197-202
The sequence of vitellogenesis as related to size increase of the oocytes of Pelagia noctiluca (Forskål) (Scyphozoa, Semaeostomeae) was examined to assess the influence of climatic factors on its reproductive period in the central and northern Adriatic Sea. From 1981 to 1985, 5 specimens with similar diameter were sampled each month. One ovary was excised from each individual and examined both with a videoanalyzer, to count the oocytes and to check their size distribution, and through histology to assess the stage of maturation in relation to the diameter. Oocytes of all stages were present in the ovaries of individuals down to a bell diameter of 3.5 cm. Thus reproduction occurs throughout the year in the central and north Adriatic Sea. However, the number of oocytes in different developmental stages in a gonad may range from a minimum value recorded in summer to two peaks in spring and autumn. The quantitative distribution is related to sea temperature and thus to metabolic rate, and to food availability.  相似文献   

20.
The contents of microelements such as Fe, Cu, Zn and As in samples of raw materials including food grade ones used in preparation of nutrient media for cultivation of antibiotic-producing organism and water were determined spectrophotometrically with using complex forming organic reagents. An original procedure for the sample combustion in the assay was developed. The natural background levels of the microelements in the nutrient media used in manufacture of some antibiotics were estimated.  相似文献   

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