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1.
Summary Pollen data from three samplers located at heights of 0.5m, 10m and 55 m were used to investigate vertical differences in pollen abundance in North-Central London. Weekly accumulative counts for all pollen types were collected from February to September 1988. Distinct variations in abundance between the sites were recorded for some pollen taxa. For example,Gramineae recorded greater abundance at the higher sampling position. Other pollen types, includingPlatanus, were recorded at consistently greater abundance at the 10 m height compared to the 55 m level. Significant differences between the pollen counts at these two heights are discussed in relation to pollen source area, the specific gravity of the pollen grain, airflow patterns of the urban area and the weather conditions affecting pollen dispersal. Tracer experiments using Lycopodium spores were employed to investigate dispersal patterns to all three sampling heights. The results from these trials are used to assist in the interpretation of data from the depositional samplers. The study reported in this paper forms part of a wider survey of 14 sampling sites examining spatial variations in pollen abundance.  相似文献   

2.
A study of the airborne pollen grains in Nsukka, Nigeria, has been carried out at two different sampling heights (1.8?m and 15?m) from February 1993 to January 1994. Twenty‐six plant families (40 genera) were identified at the lower sampling height, whilst thirty‐eight families (58 genera) were identified at the height of 15?m. A total of nine and eighteen fern spore types were observed at 1.80?m and 15?m, respectively. The quantitative results indicate that the number of pollen observed at 15?m sampling height was statistically different (p<0.05) from that observed at the height of 1.80?m. The analysis of airborne pollen grains indicates three different periods: (1) dry season, (2) rainy season, and (3) late rainy season to early dry season/Harmattan. The highest pollen abundance was recorded during the late rainy season – early dry season/Harmattan followed by that of the dry season. The predominant pollen grains and fern spores trapped at both heights include Poaceae, Casuarina equisetifolia, Milicia excelsa, Elaeis guineensis, Celtis integrifolia, Alchornea cordifolia, Amaranthaceae/Chenopodiaceae, Combretaceae/Melastomataceae, Nephrolepis biserrata, Thelypteris totta, and Dryopteris spp.  相似文献   

3.
V. I. Joy Royes 《Grana》2013,52(2):151-157
A knowledge of the pollen and fungal spores which comprise the air spora is useful as a preliminary approach to the problem of respiratory allergy. Therefore, this study of the qualitative and quantitative aspects of the air spora was done. Fungal spores were found to be numerically dominant, comprising 97.73% whilst pollen comprised 0.40% of the total material observed. A small number of types made up the majority of the fungal air spora, namely, Cladosporium, the Sporobolomycetaceae group, Diatrype, Glomerella, hyaline and coloured basidiospores, and septate fusiform spores. Seasonal periodicity studies on twenty-five fungal types showed that a high number of spores were trapped for sixteen during wet months, four during cooler months, and that five showed no seasonal trends. Mean diurnal periodicity studies for the year on the same twenty-five spore types showed that all had a maximum number of spores trapped at some time during the day. Investigation of the effect of rainfall on the numbers of spores released showed that the amount and duration of rainfall, the time of day rain occurs, and the length of the dry period preceding rain were of varying importance to particular spore types.  相似文献   

4.
Pollen data from three Burkard volumetric samplers, running simultaneously on buildings at heights of 12, 24 and 30 metres above ground level from 23rd June to 21st July 1992, were used to investigate vertical differences in pollen abundance, and correlations with six different weather parameters. Regression analysis was used to investigate the relationship between Gramineae and Urtica pollen levels and the weather variables. Pollen concentrations from the 30 m trap were consistently smaller than those from the 12 and 24 m traps for all types examined. It was concluded that pollen from local sources was not sufficiently mixed in the air to reach the 30 m trap. A delay was observed in the peak concentrations of both Urtica and Gramineae pollen between the three traps, with the maximum occurring approximately four hours earlier at 12 m than at 24 and 30 m. Circadian rhythms were also more prominent at the lower trap than at the two higher ones. Urtica and Gramineae concentrations at 12 and 24 m were correlated significantly to all the weather variables examined. Only sunshine and relative humidity were significantly correlated with pollen concentrations of Urtica and Gramineae recorded at 30 m. Climate also affected the vertical variation in pollen concentration between the three traps. Rainfall, high wind speeds and high relative humidity reduced vertical variation, whilst warm sunny weather increased it.  相似文献   

5.
Pollen and spores have been found as major biological sources of morbidity among individuals sensitive to respiratory disorders. The aim of the present study was to analyse the deposition rate of atmospheric pollen and fern spores at selected sites in Benue and Plateau states of the North-Central Nigeria between July 2015 and June 2016. This was accomplished by: (1) determining the pollen and fern spore content of each monitoring station; (2) establishing the relationship between total pollen count and meteorological parameters; and (3) comparing the recovered airborne pollen spectra with identified plants in the surrounding vegetation types of the sampling sites. The collection of atmospheric pollen was done using a modified Tauber sampler and plants in the surrounding environment of the sampling sites were enumerated. The residual solution was collected monthly and acetolysed, after which slide preparation and microscopy of the treated residue were done. Meteorological data were obtained from the Nigerian Meteorological Agency, Lagos. The results obtained reveal seasonal distribution patterns of various airborne pollen grains in the study locations. The most abundant pollen types recovered in Plateau State were produced by Syzygium guineense, Tridax procumbens, Alchornea sp., Terminalia sp., Poaceae and Amaranthaceae. Pollen types of Casuarina equisetifolia, Syzygium guineense, Tridax procumbens, Poaceae and Cyperaceae were preponderant in Benue State. Pteris sp., Nephrolepis sp. and a trilete fern spore were also represented in this study. The recovered airborne pollen spectra correspond favourably with some identified plants in the study locations. There was no significant correlation between monthly total pollen count and mean monthly values of meteorological parameters in Benue State. Air temperature and wind speed correlated significantly with monthly total pollen count in Plateau State. It is suggested that the allergenic effect of these abundant pollen types on humans should be further examined.  相似文献   

6.
Experiments comparing spore concentrations obtained by a single versus multiple Rotorod samplers in a 2 m×2 m×2 m grid were conducted within similar ecological areas and environmental conditions. Mean spore concentrations obtained by samplers at the same height above ground level were not significantly different at the p=0.05 level in all tests. However, significant differences in spore concentrations were measured among samplers operating at different heights above ground level when wind velocities were greater than 5 m/sec and no free moisture was on the spore bearing tissue. Samplers operating near a spore source measured significant differences in spore concentrations at various heights above ground but not among samplers at the same height. A single volumetric sampler will adequately measure spore concentrations for powering simulation models, but care must be taken to determine the location of the sampling unit in relationship to spore source and ecological or environmental conditions.  相似文献   

7.
We analysed pollen and spore data obtained from one continuous and two personal Burkard sporetraps during the spring months of three years (2007–2009). For the statistical analysis, the data was normalised with a log transformation, and then subjected to an ANOVA and a Pearson correlation analysis. The best time to use the personal samplers was determined from 15 years of continuous aerobiological monitoring pollen data to be between 11:00–16:00, when highest concentration was found and in a steady way. Height of sampling was compared at floor level and at 1.1 m with personal samplers; both of them were on a terrace at 6 m above the ground, but no statistically significant differences were found. The results revealed that there were apparently no differences between continuous and personal Burkard samplers for total pollen and spores. Nevertheless, distinguishing the main pollen types (i.e., Poaceae, Quercus, Olea, Cupressaceae, Plantago, and Platanus) revealed that there are some differences for Poaceae pollen only. In conclusion, personal samplers could be used to anticipate continuous monitoring data because their sampling is shorter and the results may be obtained quicker than with a continuous sampler, although they must never be considered as a replacement.  相似文献   

8.
Kramer-Collins volumetric spore samplers were used to measure concentrations of Puccinia graminis, P. recondita, Erysiphe graminis, Cladosporium, and Alternaria spores and fungal hyphal fragments within the canopy and at 1, 3, 6 and 14 m above ground level over wheat fields near Manhattan, Kansas, USA. The largest numbers of spores of each of the named fungi and hyphal fragments were trapped during hours when free moisture was not present on host leaf surfaces. As wind velocity increased, the number of spores and hyphal fragments trapped at all heights increased. Airspora trapped at the various sampling heights under all combinations of biometeorological conditions were calculated as ratios. Location and severity of infection or frequency of occurrence of the parent fungi greatly affected the percentage of propagules released in the canopy and escaped into the atmosphere. Less than 40% of P. recondita urediniospores released from tillering plants in the fall and trapped at 20–25 cm were trapped at 1 m, while only 6% of those trapped at 10 cm were trapped at 1 m. Ratios for the average number of spores trapped at 3 m: 1 m during the entire sampling period were similar for P. recondita (0.54), Alternaria (0.57), and E. graminis (0.48). However, the higher ratios that occurred with spores of P. graminis (0.72) and Cladosporium (0.76), and hyphal fragments (0.77) indicate considerable mixing of locally released airspora with airspora from exogenous sources.  相似文献   

9.
The concentration of pollen grains in the air was studied using two aerobiological volumetric Hirst-type spore traps, one at ground level and the other at a height of 16 m on a terrace. The study was carried out between 2009 and 2011, from March to June in Badajoz (SW Spain). Intradiurnal and daily pollen counts were compared with both, different meteorological parameters and the distribution of local pollen sources. Forty-six pollen types were identified and 89 % of the total grains corresponded to Quercus, Poaceae, Olea, Pinaceae and Plantago pollen types, in descending order. The mean height ratio of the daily pollen count was 1.02. Significant correlations were observed when comparing daily pollen counts for predominant pollen types at both levels. The comparisons have shown significant differences in the daily pollen count between the two samplers in the case of Olea and Pinaceae, but not for Quercus, Poaceae and Plantago. Similar results were obtained using the intradiurnal airborne pollen database. No significant correlation has been found between pollen count and the different meteorological parameters, showing no dependence on height. These differences of Olea and Pinaceae may be explained in part by the uneven distribution of the pollen sources and the disturbance by nearby buildings. The temporal variation patterns between the two sites were similar; however, taking into account the average of the data, the higher values were obtained first at the ground level and later at 16 m.  相似文献   

10.
Monitoring atmospheric fern spore and pollen loads in Singapore was initiated in June 1990. Aside from the more numerous fungal spores, fern spores and pollen grains made up 6.2–8.6% and 4.4–5.4% of the total airspora sampled, respectively. The most frequently encountered fern spores, in descending order, were those of Nephrolepis auriculata, Dicranopteris linearis, Stenochlaena palustris, Asplenium nidus, Pteridium aquilinum, and Dicranopteris curranii. For pollen grains, the most frequently encountered, in descending order, were Elaeis guineensis, Casuarina equisetifolia, Acacia auriculiformis, Kyllingia polyphylla, Podocarpus, and Poaceae pollen grains. Seasonal patterns for individual fern spore or pollen types were discernible despite the relatively uniform tropical climate in Singapore. The fern spore and pollen calendar for the period 1991–1995 was compared to that of 2005–2006 as a follow-up study to keep abreast with the rapidly changing landscape of Singapore. Diurnal patterns showing a late morning to afternoon peak period were seen in fern spores, while the peak period was in the morning for pollen types studied with the exception to oil palm pollen. Additionally, association between fern spore and pollen counts and local meteorological conditions were also analyzed and found to be highly correlated. This study has thus identified the fern spores and pollen airspora components, and determined the calendars, as well as diurnal profiles of the Singapore airspora and provides invaluable information for allergy studies by highlighting the trigger sources present in the environment.  相似文献   

11.
Measurements of atmospheric pollen concentration were made at different sites of the Po Valley, Italy, during the winter of 1978. The concentration was determined with volumetric samplers both near the ground and at different heights up to 500 m. Only Corylus and Alnus pollen grains were found during the experimental period. Due to the large quantity of grains released and the detailed information available about the source areas, the Corylus pollen was used to investigate the features of atmospheric transport. It was found that the three-dimensional patterns of pollen concentration are strongly influenced by meteorological conditions. Moreover, it appears that pollen is present in the atmosphere for a longer time with respect to the emission period, due to the relevant effect of the resuspension of the deposited pollen grains. This effect is detectable at all the sampling points, and not only near the sources.  相似文献   

12.
A study of airborne fungal spore was carried out at nine locations in the southern part of the state of Enugu, Nigeria, from March 2005 to February 2006. The aim of the study was to ascertain the variations in selected fungal spore types at the sites owing to weather conditions. The variation in airborne fungal spores of 14 taxa was studied using modified Tauber pollen traps including Alternaria, Corynespora, Curvularia, Drechslera type, Endophragmiella, Botryodiplodia, Ganoderma, Gliomastrix, Nigrospora, Pithomyces, Spegazzinia, Sporidesmium, Tetraploa and Ustilago. The frequency of the spore types recorded showed considerable variation. The highest spore counts were recorded in July, June and October. The highest numbers of fungal spores were recorded during the rainy season (June–October) to early dry season (November–December). The peak of occurrence of most selected fungal spore types was July. The highest percentages of fungal spores were documented at the recording stations Mgbowo Junction, UNTH Ituku Ozalla and Oji River Express Junction. Spearman’s correlation analyses were performed for the monthly amounts of the fungal spore types and monthly meteorological factors. The numbers of Curvularia, Nigrospora and Sporidesmium was significantly correlated with relative humidity, while those of Endophragmiella, Pithomyces and Nigrospora were significantly correlated with temperature. A significant correlation was also found between the number of Nigrospora spores and light intensity and Sporidesmium spores and wind velocity. Relative humidity and temperature seem to be the most important weather conditions affecting the frequency of the selected spore types in the atmosphere.  相似文献   

13.
Fungal spores are an ever-present component of the atmosphere, and have long been known to trigger asthma and hay fever symptoms in sensitive individuals. The atmosphere around Tulsa has been monitored for airborne spores and pollen with Burkard spore traps at several sampling stations. This study involved the examination of the hourly spore concentrations on days that had average daily concentrations near 50,000 spores/m(3) or greater. Hourly concentrations of Cladosporium, Alternaria, Epicoccum, Curvularia, Pithomyces, Drechslera, smut spores, ascospores, basidiospores, other, and total spores were determined on 4 days at three sites and then correlated with hourly meteorological data including temperature, rainfall, wind speed, dew point, air pressure, and wind direction. On each of these days there was a spore plume, a phenomenon in which spore concentrations increased dramatically over a very short period of time. Spore plumes generally occurred near midday, and concentrations were seen to increase from lows around 20,000 total spores/m(3) to highs over 170,000 total spores/m(3) in 2 h. Multiple regression analysis of the data indicated that increases in temperature, dew point, and air pressure correlated with the increase in spore concentrations, but no single weather variable predicted the appearance of a spore plume. The proper combination of changes in these meteorological parameters that result in a spore plume may be due to the changing weather conditions associated with thunderstorms, as on 3 of the 4 days when spore plumes occurred there were thunderstorms later that evening. The occurrence of spore plumes may have clinical significance, because other studies have shown that sensitization to certain spore types can occur during exposure to high spore concentrations.  相似文献   

14.
The pollen contents at different heights (1.5 and 15 m) of species of the Urticaceae family have been studied by sampling with Hirst type volumetric samplers. In order to achieve this, the two pollen types belonging to this family have been treated separately,Urtica urens-Parietaria sp. on the one hand andUrtica membranacea on the other, the latter having a smaller pollen grain. The results show that meteorological factors are bound to influence the behaviour of both these types of pollen in relation to height. With damp weather the pollen contents vary very slightly at different heights while when the weather is dry and calm, differences in pollen content at different heights become more significant. Nevertheless, when the atmosphere is stratified, the behaviour of each pollen type is different. The results show that, for most of the months considered, there is a higher pollen content ofU. membranacea at upper heights, whileU. urens-Parietaria sp. has higher levels of pollen content at a lower height. High temperatures, absence of rain and calm weather conditions favour the presence of convective phenomena which in turn create a favourable atmosphere for the vertical transportation of the small pollen grains ofU. membranacea, which are better represented in the samplers placed at 15 m.  相似文献   

15.
 The effect of an urban climate upon the spatial and temporal distribution of Deuteromycete spores was studied during 1991 using Burkard volumetric spore traps in two areas of Mexico City with different degrees of urbanization. Deuteromycete conidia formed the largest component of the total airborne fungal spore load in the atmosphere of Mexico City, contributing 52% of the spores trapped in an urban-residential area (southern area) and 65% of those in an urban-commercial area (central area). Among the most common spore types, Cladosporium and Alternaria showed a marked seasonal periodicity with significant differences in concentration (P<0.05) between the dry and wet seasons. Maximum conidial concentrations were found during the end of the wet season and the beginning of the cool, dry season (October–December). Daily mean concentrations of the predominant airborne spore types did not differ significantly between the southern and central areas. Daily mean spore concentrations were significantly correlated (P<0.05) in southern and central areas with maximum temperature (south, r = –0.35; central, r = –0.40) and relative humidity (south, r = 0.43; central, r = 0.29) from the previous day. Moreover, multiple regression analysis of spore concentrations with several meteorological factors showed significant interactions between fungal spores, relative humidity and maximum temperature in both areas. The diurnal periodicity of Cladosporium conidia characteristically showed two or three peaks in concentration during the day at 0200–0400, ∼ 1400 and 2000–2200 hours, while that of Alternaria showed only one peak (1200 to 2000 hours) in both areas. Maximum concentrations of these spores generally occurred 2–4 h earlier in the southern than in the central area. The lag in reaching maximum concentrations in the central area probably resulted from differences in the local conditions between the study areas, and from spores transported aerially into the city from distant sources. The analysis of maximum hourly concentrations of Cladosporium and Alternaria spores during 1 month of the dry season (February), and another month of the wet season (September) showed significant differences between the two study areas. Environmental factors and sources (green areas) affected diurnal changes in conidial concentration in the southern area (urbanization index, UI, 0.25), but not in the central area (UI 0.97). In general, spore concentrations were greatest in the southern area when relative humidities were low, and temperatures and wind velocities were high. It was difficult to establish effects of climatic factors on the spore concentration in the city centre. This probably results from the large amounts of air pollution, the heat island phenomenon, and from the distant origin of trapped conidia obviating aerial transport. Nevertheless, the seasonal and diurnal distributions of conidia found were similar to those reported for other tropical regions of the world. Received: 13 August 1996 / Accepted: 4 December 1996  相似文献   

16.
The prevalence of airborne fungal spores and pollen grains in the indoor and outdoor environments of a coir factory in Thiruvananthapuram district of Kerala state, India was studied using the Burkard Personal Sampler and the Andersen 2-stage Sampler for 2 years (September 1997 to August 1999). The concentration of pollen grains was remarkably lower than that of fungal spores (ratio of 1:28). There was no large difference in the concentrations and types of fungal spores between the indoor and outdoor environments, with 26 spore types found to be present indoors and 27 types outdoors; of these, 22 were common to both the environments. Aspergillus/Penicillium, Cladosporium, ‘other basidiospores’ and ascospores were the dominant spore types. The total spore concentration was highest in February and lowest in September, and it was significantly higher in 1998–1999 than in 1997–1998. Twenty viable colony-forming types were isolated from inside the coir factory. The most dominant viable fungi isolated were Penicillium citrinum, Aspergillus flavus and Aspergillus niger. The total pollen concentration was higher in the outdoor environment of the coir factory than indoors, with 15 and 17 pollen types, respectively. Grass and Cocos nucifera pollen types were dominant. The dominant spore and pollen types trapped in the two environments of the coir factory are reportedly allergenic and, consequently, workers are at risk of catching respiratory/allergic diseases.  相似文献   

17.
Qualitative and quantitative analyses of airborne fungal spores and pollen grains in four working environments (market, saw mill, poultry and cow sheds) in Thiruvananthapuram, the capital city of Kerala, India, were carried out for 2 years using Burkard Personal Slide Sampler and Andersen Two-Stage Sampler. Total spore concentration in these sites was always higher in indoor environments than in outdoor environments. Difference in concentration was not statistically significant in any of these work places except in saw mill (t test, p < 0.05). The highest spore concentration was recorded here followed by market, poultry and cow sheds. A total of 32 fungal spore types from indoor environments and 33 spore types from outdoor environments were recorded. Of them, 16 spore types were common to all the sites. Ameropsores, Cladosporium, other basidiospores, Ganoderma and Nigrospora were the dominant spore types in both indoor and outdoor environments. A total of 27 species of viable fungi from indoor and 24 species from outdoor environments were identified. Penicillium citrinum, Aspergillus flavus and Aspergillus niger were the most dominant viable fungi isolated. In contrast, total pollen concentration was always higher in outdoor environments than in indoor environments. Twenty-nine pollen types from indoor and 32 pollen types from outdoor were captured during the sampling. Poaceae, Cocos, Artocarpus, Amaranthus/Chenopodium and Tridax were the common and dominant pollen types observed in all the sites. Peak spore and pollen incidence were recorded during the late rainy and dry seasons (October–February) in both indoor and outdoor environments. The study revealed high prevalence of predominantly allergenic fungal spores and pollen grains in all the four work places. Workers/visitors are at potential risk of susceptibility to respiratory/allergic disorders.  相似文献   

18.
Persistent allergies are common in workers in florist shops but little research has been done on the reasons for this. This paper reports an investigation of occupational exposure of florists to pollen and spores in three florist shops over a 2-week period in the autumn of 2000. In each shop three sampling methods were used: Burkard continuous volumetric samplers, deposition plates and low-tac tape for surface samples, including hands of the florists and leaves of a selection of the plants. The florists kept a record of the type of work they undertook each day and of the stock amounts of flowers in the shops. The volumetric traps collected 80 pollen and spore taxa. The average concentrations recorded through the working day were generally low but short-term peak (one hour mean) concentrations of some types were found to be relatively high or very high. For a few taxa these concentrations equalled or exceeded those typical for short-term peaks in wind dispersed pollen types in the ambient air. Fungal spore concentrations of several known allergenic types were also very high for peak periods. This was most notable for Aspergillus spp. which reached extremely high concentrations in one shop, compared with typical peak concentrations in the ambient atmosphere. Low-tac tape leaf samples demonstrated that the flowers' foliage is a major source of the fungal spores. Few pollen grains or fungal spores were found on the hands.  相似文献   

19.
An aeroallergen survey in two provinces, Chiangmai in the northern and Songkhla in the southern part of Thailand which are 1 500 km apart, was done in 1986 and 1987 using a rotorod sampler. The five most common pollen types and mold spores were: Chiangmai: Mold spores: Cladosporium, rust, Fusarium, Nigrospora, 1-celled spore. Pollen grains: Mimosa, wild grasses, Urticaceae, Cyperaceae, tetrad pollen. Songkhla: Mold spores: Cladosporium, rust, Nigrospora, Papularia, 1-celled spore. Pollen grains: Casuarina, Mimosa, Urticaceae, Cyperaceae, wild grass. There were definite differences in the amount and frequency of occurrences of aeroallergens between these two provinces. Furthermore, some specific pollen and mold spores, such as tetrads and Mimosa pollen, were found only in Chiangmai, and Casuarina pollen and Papularia spores only in Songkhla. These findings might be caused by the differences in geography, plantation and meteorological data.  相似文献   

20.
Geostatistical techniques were used to assess the spatial patterns of spores of arbuscular mycorrhizal fungi (AMF) in soils from two contrasting plant communities: a salt marsh containing only arbuscular mycorrhizal and non-mycorrhizal plants in a distinct clumped distribution pattern and a maquis with different types of mycorrhiza where most plants were relatively randomly distributed. Also evaluated was the relationship between the spatial distribution of spores and AM plant distribution and soil properties. A nested sampling scheme was applied in both sites with sample cores taken from nested grids. Spores of AMF and soil characteristics (organic matter and moisture) were quantified in each core, and core sample location was related to plant location. Semivariograms for spore density indicated strong spatial autocorrelation and a patchy distribution within both sites for all AM fungal genera found. However, the patch size differed between the two plant communities and AM fungal genera. In the salt marsh, AM fungal spore distribution was correlated with distance to AM plants and projected stand area of AM plants. In maquis, spatial AM fungal spore distribution was correlated with organic matter. These results suggest that spore distribution of AMF varied between the two plant communities according to plant distribution and soil properties.  相似文献   

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