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1.
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   

2.
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   

3.
Forecasting harvests of olives destined for the production of olive oil can be based on counts of airborne olive pollen, and meteorological and agronomic observations. This study was carried out during six consecutive years (1990–1995) in the Campiña Alta (an olive-producing region in the province of Córdoba, south-west Spain). Olive pollen totals are the annual sum of the concentrations recorded for the periods that the filters of a Cour trap were exposed. The meteorological data are the values of accumulated rainfall between 1 September and the following 15 April (a date prior to the beginning of olive flowering). The agronomic data are the forecast and actual productions for the province of Córdoba, supplied by the Board of Agriculture of the Andalusian government, and the actual production of the Campiña Alta, supplied at the end of harvest by private olive-growing co-operatives. The data were combined, and four mathematical equations were obtained to forecast the crop 6 months in advance, with varying degrees of reliability. The reliability was very high for an appropriate agricultural area. The most accurate equation isY=?1.90×104+2.35X+53.94 (which forecasts the production of the Campiña Alta), whereY is the olive production (MT),X the olive pollen count,Z the rainfall prior to flowering, anda, b andc are constants. The least accurate equation is that relating olive pollen concentrations with olive production in the province of Córdoba.  相似文献   

4.
Exposure to allergens represents a key factor among the environmental determinants of asthma. The most common information available for pollinosis patients is the concentration of pollen grains in the bioaerosol and their temporal distribution. However, in recent years, discordance between pollen concentrations and allergic symptoms has been detected. The purpose of this research is to evaluate the relationship between pollen counts and the atmospheric aeroallergen concentrations in different Spanish bioclimatic areas. For the monitoring of allergen content in the air, a quantitative antigen–antibody technique combined with the Cyclone sampling methodology was used. The study was conducted during 2007 by considering some of the most common allergens that induce pollinosis in each area: Platanus and Urticaceae in Ourense and Cartagena, and Poaceae in Ourense and León. In Ourense, pollen counts and aeroallergen concentrations coincided for the three pollen types studied, and the pollen and allergen data associated with the meteorological factors were highly significant for the pollen counts. In Cartagena (for Platanus and Urticaceae) and León (for Poaceae), the low correlations between pollen counts and allergen concentrations obtained could be due to the specific bioclimatic conditions. In contrast, the higher allergen concentrations found in the atmosphere in Cartagena and León compared to Ourense could be related to the existing pollutant levels there, inducing a higher expression of plant pathogenesis-related proteins in the plants of polluted cities. The combination of pollen counts and allergen quantification must be assessed to reliably estimate exposure of allergic people to allergens in different bioclimatic areas.  相似文献   

5.
The present study describes the airborne pollen grain concentrations at two different heights (1.5 m and 15 m, respectively). The survey was carried out in 1991 and 1992, using two Burkard spore-traps, both set up at the University of Córdoba, Faculty of Sciences. Generally, and for all herbaceous plants, pollen detection started and ended around the same date on both samplers. However, in the case ofOlea europaea, the pollen was detected in advance by the sampler located at 1.5 m compared with the one located at 15 m, probably due to the fact that olives growing close to the low sampler flower before the great olive plantations located some 60 km south of the city. No significant differences between the counts of both samplers have been observed, except in the case of Urticaceae, where the sampler situated on top of the building recorded higher pollen concentrations in both years. Similar annual peaks of Urticaceae are probably due to the buoyancy of their small, light grains and the explosive pollination mechanism which liberates pollen grains from the anthers of the Urticaceae family, includingUrtica andParietaria.  相似文献   

6.
The northern area of Córdoba province (southern Spain) is characterised by a high spatial distribution of Quercus species. In Córdoba city, high airborne Quercus pollen counts are detected during spring despite the low presence of Quercus populations in the Guadalquivir Valley, where this city is located. This study sought to clarify and identify the potential origin of the different Quercus peaks detected in this city and chart the possible relationship between Quercus pollen curves and air-mass movements. For this purpose, an integrated study of daily and intra-diurnal Quercus pollen counts and back-trajectory analysis was performed over the March–June period of the years 2006–2008. The application of cluster techniques to back trajectory enabled the identification of six different types of air-mass movement. As a function of frequency, two different air-mass groups were identified: the main group comprised Local, Slower Northwest and Mediterranean movements, characterised by higher frequencies; a second group consisting of North, Faster Northwest and Southwest trajectories occurred less frequently over the study period. Although a significant correlation was observed between Quercus airborne pollen counts recorded in Córdoba city and the influence of the Mediterranean air-mass movements, the strongest positive correlation was found between North and Northwest air-mass movements and daily Quercus pollen counts. These results would confirm both that the major Quercus pollen sources are located at different distances north of the city and a new pollen source is also located south of the province, beyond the Guadalquivir valley, related to the arrival of Mediterranean air masses. The northern source appears to be linked to regional transport and the southern source to long-range transport.  相似文献   

7.
The aerobiological behaviour of Urticaceae in Trieste and the correlations with the meteorological parameters were examined. Airborne pollen was collected from 1990 to 1999 using a Hirst type spore trap (Burkard) and the data interpretation was performed according to the standard method adopted by the Italian Aeroallergen Network. The main pollen season of Urticaceae in Trieste goes from mid-April to mid-September. The highest values occur in May and June. Although different seasonal patterns are found every year, the main peak occurs on average at the beginning of May, followed by other decreasing peaks until September. Thecumulative counts vary greatly over the years, with a mean value of 18.315 p/m3. The maximum annual total pollen grains was registered in 1996 and the minimum in 1991. Spearman's correlation was used to establish the relationship between the daily pollen counts and the daily meteorological data both considering their original quantitative values and transformed values according to their day by day changes. Daily pollen concentrations present usually positive correlation with temperature, negative with rainfall and wind speed and no correlation with humidity. Better results were obtained with transformed values.  相似文献   

8.
The aim of the present paper is to study the influence of air temperature on the start of Quercus pollination in Córdoba (Andalusia, Spain). Sixteen years of pollen counts were used. The start date of the pollen season in this period varied between 26th February and 7th April. Chilling requirements and heat accumulation were taken into account although no significant correlation between chilling hours and the start date was observed. Five different predictive methods based on heat accumulation were compared in this paper: 1) Number of days over a threshold; 2) Heat Units (accumulated daily mean temperature after deducting a base temperature); 3) Growing Degrees Days (Snyder 1988), as a measure of physiological growing time; 4) Accumulated maximum temperatures; and 5) Mean maximum temperature. Results indicated that the optimum base temperature for heat accumulation was 11 Co. This threshold was used in the first three methods mentioned above. Good statistical results were obtained with the five methods, yielding high levels of explanation (p~99%). Nevertheless, the most accurate method appeared to be the Growing Degree Days (GDDo) method, which indicated that a mean of 127.3 GDDo must be accumulated from the end of the chilling period up to the beginning of the Quercus pollen season in Córdoba (South West Spain). Results were tested for predicting start dates in 1999 and 2000. The predicted dates were only one day after the actual dates.  相似文献   

9.
Spatial and temporal variations in daily grasspollen counts and weather variables aredescribed for two regions with differentbio-geographical and climatic regimes, southernSpain and the United Kingdom. Daily averagegrass pollen counts are considered from sixpollen-monitoring sites, three in southernSpain (Ciudad Real, Córdoba and Priego) andthree in the United Kingdom (Edinburgh,Worcester and Cambridge). Analysis shows thatrainfall and maximum temperatures are importantfactors controlling the magnitude of the grasspollen season in both southern Spain and theUnited Kingdom, and that the strength anddirection of the influence exerted by thesevariables varies with geographical location andtime.  相似文献   

10.
Relationships between temporal variations in the North Atlantic Oscillation (NAO) and grass pollen counts at 13 sites in Europe, ranging from Córdoba in the south-west and Turku in the north-east, were studied in order to determine spatial differences in the amount of influence exerted by the NAO on the timing and magnitude of grass pollen seasons. There were a number of significant (P < 0.05) relationships between the NAO and start dates of the grass pollen season at the 13 pollen-monitoring sites. The strongest associations were generally recorded near to the Atlantic coast. Several significant correlations also existed between winter averages of the NAO and grass pollen season severity. Traditional methods for predicting the start or magnitude of grass pollen seasons have centred on the use of local meteorological observations, but this study has shown the importance of considering large-scale patterns of climate variability like the NAO.  相似文献   

11.
In this work we establish theoretical daily pollen variation grains for the 24 taxa most frequently occurring in the atmosphere of Córdoba (Spain) during three consecutive years, namely Alnus glutinosa, Broussonetia papyrifera, Casuarina equisetifolia, Chenopodiaceae, Amaranthaceae, Cupressaceae, Cyperaceae, Ericaceae, Fraxinus, Gramineae, Mercurialis, Morus, Myrtaceae, Olea europaea, Palmae, Pinaceae, Pistacia, Plantago, Platanus hybrida, Populus, Quercus, Rumex, Typha domingensis, Ulmus minor and Urticaceae. Sampling was carried out using a Burkard spore-trap and the data collected were used to establish theoretical patterns of daily variation represented by an ideal day with accounts for the daily behaviour of each taxon.

The application of centred-data analysis (CDA) allowed two groups of taxa to be established, namely (a) those with a homogeneous variation pattern and small differences between the times of maximum and minimum occurrence, and (b) those with a heterogeneous variation pattern arising from large differences between maxima and minima or from a rather erratic variation.

As a rule, maximum pollen concentrations were found to coincide with the times of maximum sunlight and temperature.  相似文献   

12.
The pollen grains in the atmosphere in different geographical areas differ according to the species present, the pollination seasons and pollen grain concentrations, but possibly the greatest contributors to this variability are the meteorological conditions. The aim of our research is to establish a possible correlation between Parietaria pollen concentration and meteorological conditions during the period from 1991 to 1995 in the town of Alassio (north–west Italy). As far as vegetation is concerned, the Mediterranean climatic conditions support the blooming of extensive grasslands in the environment surrounding the town; these grasslands mainly comprise Urticaceae and shrubs. The study demonstrates that the most influential parameters affecting the Urticaceae grain concentration upsurge are the absence of rainfall, a maximum daily temperature of about 21 °C, and a diurnal temperature range of about 5 °C. Moreover, our aeropalinological study indicates that this last parameter has the greatest influence on Urticaceae pollination. In fact, an increase in diurnal temperature range could be responsible for a dehydration of pollens resulting in a loss in mass. This grain lightness and volatility would ultimately permit atmospheric dispersion if there is a significant wind speed. On the other hand, days with rain or high relative humidity make pollens heavier, preventing them from flying long distances and therefore partially explaining the decline in airbone pollen concentration.  相似文献   

13.
14.
Comparative ecological and aerobiological analyses of ornamental urban flora in the cities of Córdoba (Spain) and Ascoli Piceno (Italy) identified a group of plants with allergenic pollen whose behaviour is influenced by a number of factors. The geographical position and the resulting climate of both cities favoured the presence of Mediterranean species. In Córdoba, strongly allergenic evergreens introduced during the Moorish period predominated (Cupressus sempervirens, among others), while in the urban area of Ascoli Piceno, Pinaceae were abundant. In both cities, many species of American origin have been introduced for aesthetic reasons, contributing to an increase in the overall allergenicity of urban greenery. The pollen spectrum differed between the two cities: airborne Oleaceae and Cupressaceae pollen abounded in Córdoba, whilst allergenic pollen from surrounding natural environments (Corylaceae) predominated in Ascoli Piceno. These results pointed to a large number of potentially allergenic species in cities, thus highlighting the importance of greater ecological and aerobiological knowledge of allergenic species of urban ornamental flora. Avoidance of more allergenic species when planning new urban green areas could ensure healthier environments for pollen-allergy sufferers.  相似文献   

15.
The Coriolis δ air sampler is a new volumetric air sampler, dedicated to outdoor monitoring of airborne biological particles, including pollen and spores. In the present work, the performance of the Coriolis in the collection of pollen grains was evaluated in comparison with a Hirst spore trap, the most frequently used trap in aerobiological studies, in two cities of South Europe, Evora (Portugal) and Córdoba (Spain). Both concentration values are compared, and statistical analysis was carried out. The present study indicated that, in general, pollen counts for all taxa detected with the Hirst trap were higher than those detected with the Coriolis δ in both cities. In Córdoba, significant differences were detected for all taxa except for Cupressus, Olea and Pinus, while in Evora significant differences were noted for all except Pinus and Poaceae. Differences were particularly marked in species flowering during April and May. In spite of theses differences, Spearman correlation test results showed that the relationship between Hirst and Coriolis curves was always positive and significant (p > 0.01). Regards to the number of detected taxa, the results showed greater diversity for the Hirst sampler in both cities.  相似文献   

16.
Summary Urticaceae pollen monitoring was carried out, in the atmosphere of East Perugia during the summer of 1989. In summer the Urticaceae pollen shows a fluctuating diurnal trend, which was analysed daily over six 4-hour periods. The high peaks of thistaxon were recorded in the middle of the day in July and August, and in the morning in June. The percentage pattern of the daily mean pollen concentration of Urticaceae was compared with mean temperature, wind speed, relative humidity and rain, both in the non-rainy days and rainy ones. The best correlations came out comparing pollen concentration and meteoclimatic parameters during non-rainy days. The interpretation of the influence of rainfalls is very difficult owing to their peculiar features in summer.  相似文献   

17.
Data on predicted average and maximum airborne pollen concentrations and the dates on which these maximum values are expected are of undoubted value to allergists and allergy sufferers, as well as to agronomists. This paper reports on the development of predictive models for calculating total annual pollen output, on the basis of pollen and weather data compiled over the last 19 years (1982–2000) for Córdoba (Spain). Models were tested in order to predict the 2000 pollen season; in addition, and in view of the heavy rainfall recorded in spring 2000, the 1982–1998 data set was used to test the model for 1999. The results of the multiple regression analysis show that the variables exerting the greatest influence on the pollen index were rainfall in March and temperatures over the months prior to the flowering period. For prediction of maximum values and dates on which these values might be expected, the start of the pollen season was used as an additional independent variable. Temperature proved the best variable for this prediction. Results improved when the 5-day moving average was taken into account. Testing of the predictive model for 1999 and 2000 yielded fairly similar results. In both cases, the difference between expected and observed pollen data was no greater than 10%. However, significant differences were recorded between forecast and expected maximum and minimum values, owing to the influence of rainfall during the flowering period. Received: 25 October 2000 / Revised: 26 February 2001 / Accepted: 28 February 2001  相似文献   

18.
An aerobiological study was made of Urticaceae pollen in the city of Granada, relating the mean values of the daily counts to meteorological parameters. Sampling was carried out with a Burkard seven‐day‐recording spore trap from October 1992 to September 1997. This pollen type has an extremely long main pollen season (MPS), with maximum counts in (January) February, March and April, causing numerous cases of human pollinosis throughout the entire Mediterranean region, including Granada. A highly constant intradiurnal variation pattern was obtained showing that the maximum peaks usually occur between 12.00 and 20.00. According to Spearman's correlation coefficient, during the pre‐peak period the parameters which have the greatest effect on the levels of this type of pollen are daily and accumulated temperature and sunshine, accumulated rainfall, and wind direction from the third quadrant; during the post‐peak period these same variables presented significantly negative coefficients. Daily rainfall and relative humidity presented negative coefficients during the entire MPS. The maximum daily temperature was the variable which provided the closest match with the theoretical predictive pattern presented here.  相似文献   

19.
Two of the most frequently used methods of pollen counting on slides from Hirst type traps are evaluated in this paper: the transverse traverse method and the longitudinal traverse method. The study was carried out during June–July 1996 and 1997 on slides from a trap at Worcester, UK. Three pollen types were selected for this purpose: Poaceae, Urticaceae and Quercus. The statistical results show that the daily concentrations followed similar trends (p < 0.01, R-values between 0.78–0.96) with both methods during the two years, although the counts were slightly higher using the longitudinal traverses method. Significant differences were observed, however, when the distribution of the concentrations during 24 hour sampling periods was considered. For more detailed analysis, the daily counts obtained with both methods were correlated with the total number of pollen grains for the taxon over the whole slide, in two different situations: high and low concentrations of pollen in the atmosphere. In the case of high concentrations, the counts for all three taxa with both methods are significantly correlated with the total pollen count. In the samples with low concentrations, the Poaceae and Urticaceae counts with both methods are significantly correlated with the total counts, but none of Quercus counts are. Consideration of the results indicates that both methods give a reasonable approximation to the count derived from the slide as a whole. More studies need be done to explore the comparability of counting methods in order to work towards a Universal Methodology in Aeropalynology. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

20.
The prevalence of red deer hypodermosis and the life cycle of Hypodermia diana Brauer 1858 in three provinces of the south of Spain, Córdoba, Jaen and Ciudad Real, were studied by inspecting 254, thirty-eight and thirty-five deer from each province respectively. The prevalence of infestations was: Córdoba, 87.75%; Jaen, 92.10%, Ciudad Real, 91.42%. From this we deduced an overall prevalence of 88.67%, comprising 88.23% in male deer and 89.96% in female deer. The intensity of the parasitism in 213 of the 245 animals from Córdoba varied between one warble per animal to more than 100 in 28 of the inspected animals. The chronology of the life cycle during the hunting period (October to the end of February) was investigated.  相似文献   

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