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1.
A qualitative and quantitative analysis of airborne pollen and spores was carried out over 2 years (from September 1987 to August 1989) in the city of León. Slides were prepared daily using a volumetric pollen trap, which was placed on the Faculty of Veterinary Science building (University of León) 12m above ground-level. Fifty-one pollen types were observed; the most important of these were: Cupressaceae during the winter,Pinus andQuercus in spring, and Poaceae, Leguminosae and Chenopodiaceae in the summer. The results also showed the existence of a rich mould spore assemblage in the atmosphere. The group of Amerospores (Penicillium, Aspergillus andCladosporium) as well as Dictyospores (Alternaria) were the most abundant;Puccinia was common in the air in August. Fluctuations in the total pollen and spores m3 of air were compared with meteorological parameters (temperature, relative humidity and rainfall). From the daily sampling of the atmosphere of León, considering the maximum and minimum temperature and duration of rainfall, the start of the pollen grain season was observed generally to coincide with a rise in temperature in the absence of rain.  相似文献   

2.
3.
The present study analyzes the behaviour ofAlnus andBetula pollen in the atmosphere of the town of Santiago de Compostela (N.W. Spain) from January 1993 to December 1995. The main pollination period of both taxa is identified for each sampling year, which, in the case ofAlnus, took place in January and February and, forBetula, during April.Alnus andBetula pollen are found in very high quantities in the atmosphere of Santiago de Compostela, representing 5% and 12% respectively of the total annual pollen that was counted. We studied the correlation between pollen content each year for both taxa and the main meterological parameters (average, maximum and minimum temperatures, precipitation and hours of sunshine). Finally, we analyzed the diurnal behaviour model for each taxon. ForAlnus, the maximum concentrations were found around 20:00 h, while, in the case ofBetula, the main pollen concentration took place between 15:00 h and 20:00 h in 1993 and 1994, and at 00:00 h in 1995.  相似文献   

4.
During our investigation on microfungi in Antoniusheim, Fleissenbach und Merfelderbruch near Dülmen in Münsterland in the years 2005 and 2006 we were able to collect and identify 25 microfungi on Alnus glutinosa (L.) GAERTN. Among them are some which are very rare in Germany linke Phragmoporthe conformis (Berkley & Broome) Petrak, Cryptosporiopsis alnea (Rostr.) Petr., Prosthecium auctum (Berk. & Broome) Petr., Taphrina alni-incanae (Kun.) Magn. [= T. Amentorum (Sadeback) Rostrup], Cryptodiaporthe oxystoma (Rehm.) Z. Urb., Cladosporium alnicola Bub. & Vleug. [= C. Herbarum (Pers.)], Erysiphe penicillata (Wallr.) Link, Melampsoridium betulinum Kleb., Bacterodesmium longisporum M.B. Ellis, Marssonina alni Karak. Asteroma alneum (Pers.: Fr.) Sutton . All collected species can be found in the text.  相似文献   

5.
《Acta Oecologica》2000,21(1):29-35
Ecological correlates of the distribution of nine common leiodid species were studied in three river valleys on the southern side of the Cantabrian Range in León, in northern Spain. Soil moisture content, substrate temperature variability and type of organic matter proved to be the key factors determining the distribution of species of this group. These factors may have important effects not only at the local level but also on the medium scale.  相似文献   

6.
This study was undertaken in order to understand thebehaviour of airborne pollen grains, namely therelationship between their concentrations andconcomitant meteorological parameters, at differentaltitudes (ground level, 200, 400 and 600 m) of thelower atmosphere and its daily variations over onesite (the experimental farm of the University ofLeón). The experimental design involved a tetheredballoon (2.25 m3), an ADAS remote meteorologicalstation and an original radio controlled three headedpollen and spore sampler (called GABIS) using theRotorod design. Each head sampled a differentaltitude, while two control samples were taken atground level. Twenty-one takeoffs could be realized inthe 5 weeks period between end of May and end of June1997. Sampling was done early in the morning and sampling time at each altitudewas of 15 minutes. Results show that 45 differenttypes of pollen grains could be collected at this timeof the year and that significant variations could beobserved in the behaviour of the pollen cloud on a dayto day basis, probably because of differentmeteorological situations. Contrary to what isgenerally believed, pollen was in most cases moreabundant at higher altitude – on average by 30% ascompared to ground level – making evident anaerobiological layer of transport at about 500 m aboveground. This was especially the case for trees (Quercus and Castanea). The atmosphere MixingRatio was the most explicative factor at 200 m, whiletemperature dominated significance analysis at both400 and 600 m.  相似文献   

7.
The abomasa of naturally infected ewes (407) and lambs (190) from four areas of León were collected weekly over 2 years in the abattoir of León (north-west Spain). The major species and morphs found were Teladorsagia circumcincta and Trichostrongylus axei and to a lesser extent Marshallagia marshalli and Teladorsagia trifurcata. The putative interactions between species were assessed by Euclidian distances based on the results of multivariate analyses. The estimation of interaction was either based on mean intensities of worm burdens or on frequencies of nematode species within individual hosts. The areas, years, seasons and categories of sheep (ewes or lambs) did not influence the interaction estimates. These were not dependent upon the size of worm burden. The majority of interactions were positive. Slight negative interactions were found only with T. circumcincta-T. axei, T. circumcincta-M. marshalli and M. marshalli-T. axei. Positive interactions were recorded between the less frequent species.  相似文献   

8.
During 1991 and 1992, hourly measurements were taken of solid particulates (size, 22–25 μm).Olea and grass pollen and spores. The results were then compared with symptoms recorded in patients consulting the Allergy Unit during the period of highest pollen concentrations (April–June). The spore-trap slides were studied by spectrophotometry in order to analyse the total solid particulates content in the air as a possible synergic agent of the pollen. This allowed the volume of material present in the air to be determined and expressed as a percentage of total optical density (OD). Allergy symptom data were obtained from the study of subjective clinical records completed by patients, who were required to note down the severity of a selected series of symptoms every 4 h using a scale from 0–3. The results showed a clear link during the season between hourly peaks and pollen concentrations, and the different patterns of response associated with the dominant pollen types. An attempt has been made to determine whether a relationship exists between the increment of the optical density and the symptomatic response. The positive relationship encountered seems to indicate that a synergic agent takes an active part in the effects produced by pollen in the patients.  相似文献   

9.
Ozone is a secondary air pollutant that has received extensive attention in the literature, mainly because of the adverse effects that exposure to it can cause, particularly in vegetation during the growing season. Because meteorological conditions strongly influence the efficiency of photochemical processes leading to ozone formation and destruction, ground-level ozone air pollution is currently being considered as a regional-scale phenomenon rather than a local one. This role of O3 as a regional-scale pollutant often implies the handling of large data sets in order to obtain information about its spatial and temporal variability patterns over a given broad region. Rotated principal component analysis (RPCA) is known to be one of the most powerful mathematical tools that can be used to achieve this aim. RPCA was applied in this paper to the summer and winter hourly time series of ground-level O3, concentrations recorded during 2 consecutive years (1996–1997) at 26 urban and suburban sites in Castilla-León (Spain). This procedure permitted the identification of different subregions where O3 concentrations show different spatio-temporal variability patterns. These variability patterns are mainly associated with the interaction of regional-level meteorological and anthropogenic factors. Some differences between winter and summer patterns were also found. Received: 5 April 1999 / Revised: 27 December 1999 / Accepted: 27 December 1999  相似文献   

10.
The main goal of the present study was to provide a detailed analysis of olive pollen transport dynamics in the province of Córdoba (south-western Spain) by applying back-trajectory analysis. Pollen data from 2006 and 2007 were analysed at four monitoring sites: Córdoba city in the centre of the province, Baena and Priego de Córdoba located in the south, and El Cabril reserve (Hornachuelos Natural Park) in the north. Particular attention was paid to nine episodes of high pollen counts. Synoptic surface maps were used, and kinematic back-trajectories (3D) were computed using the hybrid single particle Lagrangian integrated trajectory model (HYSPLIT) at 500 m above ground level, run with a time-step of 6 h over a period of 36 h. Findings were analysed in conjunction with daily and bi-hourly airborne pollen data, field phenological data and hourly surface meteorological data recorded at nearby stations: temperature, relative humidity, rainfall, wind direction and wind speed. The results identified two pollen source areas over the Córdoba province, the largest one located in the south, affecting Baena, Priego de Córdoba and Córdoba city, and one smaller located in the west, which determines mainly the pollen cycle over the north of the province, El Cabril. In addition, two air mass circulations were found, one coming from the south and crossing the main olive pollen sources very close to the surface and being frequently associated with higher pollen counts, and the other coming from the west and, in the episodes investigated, influencing mainly the north of the province.  相似文献   

11.
The dynamics of 15 taxa pollen seasons in Kraków, in 1991–2008 was monitored using a Burkard volumetric spore trap of the Hirst design. The highest daily pollen concentrations were achieved in the first half of May, and they were caused mainly by Betula and Pinus pollen. The second period of the high concentrations took place from the middle of July to the end of August (mainly Urtica pollen). Tree pollen seasons were shorter (18–24 days) in comparison with the most herbaceous pollen seasons (73–89 days), except at Artemisia and Ambrosia seasons (30 and 24 days, respectively). The season phases (percentyles) of the spring and late-summer taxa were the most variable in the consecutive years. The highest annual sums were noted for Urtica, Poaceae (herbaceous pollen seasons) and for Betula, Pinus, Alnus (tree pollen seasons), and the highest variability of annual totals was stated for Urtica, Populus, Fraxinus and the lowest for Ambrosia, Corylus, Poaceae. For the plants that pollinate in the middle of the pollen season (Quercus, Pinus and Rumex), the date of the season start seems not to be related to the season end, while for late pollen seasons, especially for Ambrosia and Artemisia, the statistically negative correlation between the start and the end season dates was found. Additionally, for the most studied taxa, the increase in annual pollen totals was observed. The presented results could be useful for the allergological practice and general botanical knowledge.  相似文献   

12.
13.
This study sought to compare airborne pollen counts for a number of common herbaceous species (Plantago, Chenopodiaceae–Amaranthaceae, Rumex, and Urticaceae) in two cities with differing weather conditions, Córdoba (Southwestern Spain) and Poznan (Western Poland). Pollen seasons for these species were studied from 1995 to 2005. Aerobiological sampling was performed using a Hirst type 7-day spore trap, in accordance with the procedure developed by the European Aerobiology Network. A Spearman correlation test was used to test for correlations between meteorological parameters and daily airborne pollen counts. The Spearman correlation test and the Wilcoxon signed ranks test were also used to compare mean daily pollen counts for the two study sites. In Córdoba, the pollen season generally started around two months earlier than in Poznan, and also lasted longer. These findings were attributed to the presence of a larger number of species in Córdoba, with overlapping pollen seasons, and also to more favorable weather conditions. Trends in pollen season start dates were fairly stable over the study period, with a slight tendency to delayed onset in Córdoba and a modest advance in start date in Poznan. The pollen season end date also remained reasonably stable over the study, with only a slight tendency for the season to end earlier in Córdoba and later in Poznan. A clear trend towards declining annual pollen counts was recorded over the study period for all pollen types in both cities.  相似文献   

14.
For two years fortnightly malacological samplings were carried out to collect Lymnaea truncatula (Mollusca; Basommatophora) at five points in the upper and middle Porma river basin, León, Spain. The highest numbers of snails were collected in September, May and November. Of the 5486 molluscs examined, 11.41% harboured F. hepatica (Trematoda; Digenea) with an average intensity of 20.14. In general, the values of both infection prevalence and intensity increased with the size of the snails. It was in October when the highest figures for each parameter mentioned above were detected (18.73% and 28.48, respectively). The chi-square test showed statistically significant differences in relation to the infection prevalence among the groups of molluscs established according to: their length; the months in which they were collected; the sampling localities; monthly average ambient temperature; precipitation during the collection. Similarly, statistically significant differences were detected in the intensity of the infection among the groups of molluscs previously established, except for that based on the values of precipitation. Generally, parasites were found in the same snail at different stages of development. It seems that most mollusc infections occur in February-March and at the end of summer-beginning of autumn periods. The highest rate of rediae with mature cercariae ready to be shed were detected between September and December. Metacercariae in the grass samples were also observed at the end of autumn. For this reason, this period could be considered as the most suitable for infection of the definitive hosts to take place.  相似文献   

15.
Lake Gallocanta has undergone drastic changes during the last thirteen years. Water level changed from a high level (Zmax = 2 m) to total dryness in 1985. From 1986 to 1988 slow refilling occurred. The water volume fluctuations have been studied in relation to climatic variations recorded for that period. Variations in the major dissolved ions were related to water volume fluctuations from data at two different stages, one corresponding to the drying phase and another to the refilling phase. Mineralogical composition of the salts precipitated at different stages was examined by X-ray diffraction. Interstitial water and mineralogical composition of recent sediments were also studied along a transect through the lake.The water column decrease from 1977 to 1985 is related to decreasing annual rainfall (500-250 mm respectively). The refilling in 1986–1988 is due to high annual rainfall (537 mm). In addition to these fluctuations, seasonal changes of the water level between 20 and 50 cm occurred every year.Gallocanta is a Na-Mg-Cl-(SO4) type lake. During the drying period a typical salt enrichment occurs with linear relationships between TDS, Cl, Na and K. Alkalinity is linearly correlated with Ca at relatively low salinities. As salinity increases a linear relationship between Ca and SO4 is observed. Minerals formed from the brine are halite, bischofite, epsomite, hexahydrite, mirabilite, gypsum, aragonite, calcite and dolomite. The molar ratio Mg/Ca of the interstitial water changes from 1.5 along the shorelines, where calcite and aragonite precipitate, to 40 in the center of the lake. Sediment cores from the central part of the lake show aragonite in the top layers, magnesian calcite and low proportions of quartz and illite, while at 20 cm depth a high proportion of gypsum is present. In contrast, cores from the shore of the lake are mainly composed of low magnesium calcite in the top layers and low magnesium calcite together high magnesium calcite and dolomite between 30 and 70 cm depth. Gypsum deposits only occur in significant proportions at 80–100 cm depth.The refilling process showed relationships between volume and salt concentration following the Langbein model. The salt mass in solution decreased about 50% from the drying to the refilling phase. However, Mg content decreased about 70 % for the same period, suggesting a contribution of this element to the dolomite formation.  相似文献   

16.
Prior to an outbreak in Castilla y León in December 1997, tularaemia was practically non-existent in Spain. In this paper we studied the prevalence of antibodies against Francisella tularensis in a representative sample of the population (4825 people) from Castilla y León (Spain) in samples collected before this outbreak. Antibodies against F. tularensis were detected in nine (0.19%) of the 4825 sera, with antibody titres ranging from 1/20 to 1/160. Of these nine sera, one was positive in seroagglutination against Brucella. Seroagglutination against other bacteria (Yersinia enterocolitica O:9 and O:3 and Proteus OX19) was negative in all sera. Seroprevalence of antibodies in females was 0.20% and 0.17% in males; no statistically significant differences were found in prevalence in terms of sex, age or province.  相似文献   

17.
The royal burial chamber of what is today the Collegiate-Basilica of St. Isidoro in León, Spain, built and remodeled between the 10th and 13th centuries and in the 20th century renamed the Kings' Pantheon, has 13 royal tombs that were opened in the presence of the Abbot-Prior of the Collegiate to enable a group of researchers to obtain all possible information from the royal remains. Several samples were sent to the Parasitology Unit of the Animal Pathology (Animal Health) Department at the Veterinary Faculty of León (Spain). In all the tombs, eggs and remains of nonparasitic mites were observed. In a piece of linen cloth from the bottom of 1 tomb, an Anoplocephala perfoliata egg was found. Furthermore, 4 mummified bodies were found. In 2 of these, those belonging to Infantes María and Fernando, Ascaris lumbricoides eggs were found and in the latter Trichuris trichiura eggs. We have not found in the literature reviewed any records of studies of this kind carried out in Spain.  相似文献   

18.
Airborne pollen counts are mainly determined using a volumetric suction sampler based on the impact principle, that is, a Hirst-type spore trap. As a consequence of their volumetric nature, samplers detect pollen from a wide area, and therefore, a single sampler is frequently used to acquire information on airborne pollen counts for the whole city. The main goal of the present study was to compare airborne pollen counts at two sites located at opposite ends (south-west vs. north-east) of the southern Spanish city of Córdoba, to assess the advantages and disadvantages of using more than one sampler in the city. Also, a comparative study was carried out using two samplers at the same site, in order to confirm the efficiency of the samplers. Results revealed that data from one volumetric sampler—located within a city of medium size with uniform topography and vegetation conditions—are sufficient to establish monitoring of the main airborne pollen types, the pollen seasons involved and the timing of peak counts. For clinical studies, however, data on pollen counts in specific areas of the city may be of value, since pollen intensity may vary from one district to another, mainly in the case of ornamental plants with a local distribution inside the city. Comparison of data obtained by the two samplers running at the same site indicated that potential inter-site differences could not be attributed to differences in sampler efficiency.  相似文献   

19.
The influence of meteorological parameters on the dispersion of airborne pollen has been studied by several authors. Olive pollen is the major cause of allergy in southern Spain, where a large part of the arable surface area is given over to olive cultivation. Daily pollen forecasts provide important information both for pollen-allergy sufferers and for agronomists trying to achieve a better biological understanding of variations in airborne olive pollen levels. The main purpose of this paper is to study, by means of short-term statistical analysis, the effect of meteorological parameters on airborne olive pollen concentrations in the city of Cordoba (south-western Spain). Twenty-one-year (1982–2002) aerobiological and meteorological databases were used. Correlation and multiple regression analyses were used to study the relationships between olive pollen levels and several meteorological parameters. Statistical analysis was applied both to the whole pollen season and to the pre-peak period. Daily meteorological parameters, such as accumulated mean temperature, accumulated sunlight hours, and accumulated rainfall were used as independent variables in both statistical analyses. Accumulated meteorological variables were of the greatest value in most regression analysis equations, heat-related variables being the most important.  相似文献   

20.
In the locality of Colle (Cantabrian Zone, NW Spain), the upper part of the Valporquero Shale Formation (Emsian, La Vid Group) contains an interval of shales and marlstones (barren, greenish-grey shales and fossiliferous, greenish-grey or reddish shales/marlstones) with beds and packages of homogeneous and cross-bedded skeletal limestones. Metre-scale mud mounds and coral biostromes occur encased in the fossiliferous reddish and greenish-grey shale/marlstones, respectively, with the coral biostromes overlying conspicuous skeletal limestone bodies. These rocks were deposited on a carbonate ramp, ranging from above storm wave base for the cross-bedded skeletal limestones to below the storm wave base for the remaining deposits, organic buildups included. The vertical stacking of these facies and the occurrence of the two types of buildups are interpreted to reflect the interplay among several (possibly 4th and 5th) orders of relative sea-level variations, during a 3rd-order highstand. Coral biostromes occur in early 5th-order transgressive system tracts developed within late 4th-order highstand, and are interpreted to have thrived on a stable granular substrate (skeletal limestones) in non-turbid waters, being later aborted by the onset of muddy sedimentation. Biostrome features suggest that they developed under environmental conditions essentially different from those related to the sedimentation of their granular substrate. Mud mounds occur in 5th-order transgressive and early highstand system tracts tied to early 4th-order sea-level rise. Field relationships suggest that mud mounds grew coevally with muddy sedimentation, with high-frequency variations in carbonate vs. terrigenous mud sedimentation influencing their development.An erratum to this article can be found at  相似文献   

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