Herb pollen representation in surface moss samples from mown meadows and pastures in western Norway

Grazed and mown vegetation types in western Norway were investigated with the aim of describing their modern pollen/vegetation relationships as an aid to the interpretation of fossil pollen diagrams. Pollen surface samples and vegetation data were obtained from 186 square metre plots within 39 different sites of 10×10 m. Scatter plots that show the relationship between pollen percentages and vegetation percentages are presented forTrifolium pratense-type,Trifolium rcpens-type,Lotus, Campanula-type,Succisa, Ranunculus acris-type,Cirsium-type, Asteraceae Cichorioideae,Achillea-type,Potentilla-type, Apiaceae,Rumex sect.Acetosa, Galium-type, Cyperaceae,Calluna, Plantago lanceolata and Poaceae. Pollen representation factors relative to Poaceae (R_rel) are calculated for 54 pollen taxa. Differences in the values from different geographical areas were found in the case of some taxa, due to either different genera or species being included in the pollen taxa and/or to the different representation of high pollen producers in the different regional vegetation types. Background pollen influences the estimates for taxa such asR. sect.Acetosa, P. lanceolata, Poaceae, Cyperaceae, andCalluna, and an extended R-value (ERV) model was used to investigate the magnitude of this pollen component. Groups of roughly similar pollen representation were identified and factors to convert pollen percentages to vegetation abundances are suggested.     

Fluctuations and trends in airborne concentrations of some abundant pollen types,monitored at Vienna,Leiden, and Brussels

The annual sums of daily airborne pollen concentrations fluctuate from year to year. It has been suggested that for some taxa there is a regular or alternating pattern in these fluctuations. On the other hand, environmental changes may lead to decreasing or increasing trends in airborne pollen concentrations. These two phenomena can only be studied reliably on the basis of long-term volumetric observations of abundantly occurring pollen types. For this study two arboreal (Betula and Quercus) and two herbaceous (Poaceae and Urtica) types were chosen.

For some of these pollen types a weak but significant trend is observed. For the arboreal types (Quercus and Betula) there appears to be a rather constant biennial fluctuating rhythm.     

Intradiurnal variation of allergenic pollen in the city of Porto (Portugal)

This study reports the hourly distribution of the allergenic airborne pollen types more abundant in the atmosphere of Porto (Portugal) during the studied period. This knowledge will allow an adequacy daily routine for allergic patients during the hours of higher airborne concentrations. The airborne pollen concentration was continuously performed from January 2003 to December 2007 in the city of Porto using a Hirst-type volumetric sampler. Urticaceae, Cupressaceae, Acer spp., and Plantago spp. airborne pollen presented higher concentrations in the morning, while Alnus spp. and Betula spp. pollen were mainly present during the afternoon. Olea europaea and Platanus spp. pollen were regularly distributed along the day, while Poaceae and Pinus spp. pollen presented two diurnal maxima.     

Trends in atmospheric concentrations of weed pollen in the context of recent climate warming in Poznań (Western Poland)

A significant increase in summer temperatures has been observed for the period 1996–2011 in Poznań, Poland. The phenological response of four weed taxa, widely represented by anemophilous species (Artemisia spp., Rumex spp. and Poaceae and Urticaceae species) to this recent climate warming has been analysed in Poznań by examining the variations in the course of airborne pollen seasons. Pollen data were collected by 7-day Hirst-type volumetric trap. Trends in pollen seasons were determined using Mann–Kendall test and Sen’s slope estimator, whereas the relationships between meteorological and aerobiological data were established by Spearman’s rank correlation coefficient. Significant trends in pollen data were detected. The duration of pollen seasons of all analysed taxa increased (from +2.0 days/year for Urticaceae to +3.8 days/year for Rumex), which can be attributed to a delay in pollen season end dates rather than earlier start dates. In addition, the intensity of Artemisia pollen seasons significantly decreased and correlates with mean July–September daily minimum temperatures (r?=??0.644, p?Rumex pollen seasons. The results of this study show that observed shifts in weed pollen seasons in Poznań, i.e. longer duration and later end dates, might be caused by the recorded increase in summer temperature. This influence was the strongest in relation to Artemisia, which is the taxon that flowers latest in the year. The general lack of significant correlations between Rumex and Urticaceae pollen seasons and spring and/or summer temperature suggests that other factors, e.g. land use practices, could also be partially responsible for the observed shifts in pollen seasons.     

Variations in airborne pollen in central and south-western Spain in relation to the distribution of potential sources

The present study seeks to compare daily and hourly airborne pollen concentrations at eight different stations in Castilla-La Mancha (central Spain) and Extremadura (south-western Spain) and assess pollen distribution sources. Sampling stations were located 69–440 km apart in a straight line in Albacete, Toledo, Talavera de la Reina and Ciudad Real in Castilla-La Mancha, and in Badajoz, Plasencia, Santa Amalia and Zafra in Extremadura. Airborne pollen was collected using Hirst-type volumetric spore traps. Quercus was the most abundant pollen type at all stations except for Ciudad Real, where Olea pollen predominated. Comparisons of daily data between pairs of stations revealed statistically significant positive correlations in all cases for Poaceae and Olea. Comparisons of hourly data between stations indicated greater differences than daily data. Analysis of correlation coefficients and straight-line distances between stations revealed a strong negative correlation. Analysis of total airborne pollen data for the eight sampling stations suggests that airborne pollen concentrations decrease from west to east and from south to north, partly reflecting dominant wind patterns. A clear correlation was observed between airborne pollen concentrations and the surface area covered by olive crops in a 50 km radius around the sampling stations.     

Annual pollen spectrum variations in the air of Bratislava (Slovakia): years 2002–2009

Pollen grains in the atmosphere of Bratislava were quantitatively and qualitatively analysed during an 8-year period (2002–2009) using a Burkard volumetric pollen trap. The mean annual total pollen grain count recorded during this period was 36,608, belonging to 34 higher plant taxa (22 trees and/or shrubs and 12 herbaceous species). The maximum annual total pollen grain count (50,563) was recorded in 2003 and the minimum (14,172) in 2009. The taxa contributing the highest concentration of pollen grains were Betula, Urticaceae, Cupressaceae-Taxaceae, Populus, Pinus, Poaceae and Ambrosia. During the study period, there was a remarkable increase in the number of pollen grains from February to April, with the highest daily mean pollen counts recorded in April. Total pollen concentration began to decrease markedly in May, but there was a second increase between July and August, followed by a decrease in September. The timing and length of the pollen seasons varied. Betula and Poaceae showed a rather constant 2-year fluctuating rhythm. The relationships between airborne pollen concentration and meteorological variables were assessed. Based on these results, the first pollen calendar in Slovakia has been constructed for the area of Bratislava, which provides a great deal of useful and important information.     

Comparison of some pollen concentrations in Finland and the Estonian SSR

Summary Pollen and spore concentrations were compared in Tartu, Estonia and in three sites in Finland (Turku, Kuopio and Oulu) during May–September 1989. The onset ofQuercus, Pinus, Poaceae,Urtica andRumex flowering started earlier in Tartu than at any site in Finland. The flowering ofJuniperus andArtemisia, on the other hand, began earlier in Turku and Kuopio than in Tartu.Pinus andJuniperus showed a significant correlation (number of pollen grains at the same date) between Tartu and Turku and between Turku and Kuopio. Poaceae andUrtica were correlated between all the sites, as wasRumex except between Tartu and Turku.Artemisia was correlated between Tartu and Turku, Turku and Oulu, and Kuopio and Oulu.Cladosporium correlated between Tartu and Turku. The pollen seasons of Poaceae,Urtica andRumex are prolonged towards the south.     

The pollen season dynamics and the relationship among some season parameters (start,end, annual total,season phases) in Kraków,Poland, 1991–2008

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.     

Airborne pollen from allergenic herbaceous plants in urban and rural areas of Western Pomerania,NW Poland

This paper presents the course of the pollen season of selected allergenic taxa (Rumex spp., Plantago spp., Urtica spp. and Chenopodiaceae) in two towns with different degrees of urbanisation (urban, the city Szczecin, and rural, the village Gudowo in Western Pomerania, northwest Poland). The study was conducted in the years 2012–2014 with the volumetric method. The pollen of allergenic herbaceous plants was present in the air from early May until the end of September. From among the taxa studied, the genus Rumex is characterised by the longest pollination period, while the genus Urtica by the shortest. The highest percentage contribution of pollen grains to the total pollen count in the air reaching over 90% is from nettle. The pollen seasons determined for the majority of taxa are longer in the city, however the mean pollen grain counts in the air are higher for the rural area.     

Phenological records as a complement to aerobiological data

Phenological studies in combination with aerobiological studies enable one to observe the relationship between the release of pollen and its presence in the atmosphere. To obtain a suitable comparison between the daily variation of airborne pollen concentrations and flowering, it is necessary for the level of accuracy of both sets of data to be as similar as possible. To analyse the correlation between locally observed flowering data and pollen counts in pollen traps in order to set pollen information forecasts, pollen was sampled using a Burkard volumetric pollen trap working continuously from May 1993. For the phenological study we selected the main pollen sources of the six pollen types most abundant in our area: Cupressaceae, Platanus, Quercus, Plantago, Olea, and Poaceae with a total of 35 species. We selected seven sites to register flowering or pollination, two with semi-natural vegetation, the rest being urban sites. The sites were visited weekly from March to June in 2007, and from January to June in 2008 and 2009. Pollen shedding was checked at each visit, and recorded as the percentage of flowers or microsporangia in that state. There was an association between flowering phenology and airborne pollen records for some of the pollen types (Platanus, Quercus, Olea and Plantago). Nevertheless, for the other types (Cupressaceae and Poaceae) the flowering and airborne pollen peaks did not coincide, with up to 1 week difference in phase. Some arguments are put forward in explanation of this phenomenon. Phenological studies have shown that airborne pollen results from both local and distant sources, although the pollen peaks usually appear when local sources are shedding the greatest amounts of pollen. Resuspension phenomena are probably more important than long-distance transport in explaining the presence of airborne pollen outside the flowering period. This information could be used to improve pollen forecasts.     

Airborne fungal spores in urban and rural environments in Poland

The concentrations of airborne fungal spores were measured during 2001–2002 in two sites in Poland—one in the city and the other in the countryside. The sites differed in habitat characteristics, such as urbanisation level, vegetation and microclimate. The aim of the study was to determine if, and in which way, land use type would affect spore occurrence. The volumetric method was used, and ten easily identifiable spore types were sampled and anyalysed: Alternaria, Botrytis, Cladosporium, Epiccocum, Ganoderma, Pithomyces, Polythrincium, Stemphylium, Torula and Drechslera. The season of spore occurrence was determined using the 90% method. The fungal spores studied were very frequent in the air (in most instances at a frequency higher than 50%). The most common spores were those of Cladosporium, with a frequency range of 83.1–90.5%. In both years the proportion of Cladosporium spores was statistically significantly higher in the city. In both 2001 and 2002 the total seasonal sum of all the spores was higher in the countryside than in the city as was the Seasonal Fungal Index (SFI) values and average concentrations of Botrytis, Ganoderma and Torula. These latter three genera are usually represented as pathogens of plants. The mean spore concentrations of most taxa were significantly higher in the rural environment. Correlation coefficients between daily concentrations at both sites for most of the taxa studied were significant, but with lower correlation values between variables. Such results indicate that the values from the sites are weakly interdependent. The study confirms that land use type may very likely have an impact on the course of spore occurrence, the mean daily concentrations of spores as well as SFI values.     

Seasonal distribution of pollen in the atmosphere of Darwin,tropical Australia: Preliminary results

Pollen loads in the atmosphere of Darwin, a city located in the wet‐dry tropics of Australia, have been monitored for the period March 2004 to November 2005 as part of a large research program looking at atmospheric particles and human health. Seven pollen types dominate the pollen spectrum, the herbaceous families of Poaceae (grasses) and Cyperaceae (sedges), as well as several native tree and shrub taxa, Acacia, Callitris, Casuarina, Arecaceae and Myrtaceae. The pollen loads were found to have a strong seasonal component associated with the alternating wet (November to March) and dry (April to October) seasons of the region. Seventy percent of the yearly pollen load is captured during the dry season, with the peak pollen period occurring at the onset of the dry season (April–May) when most grasses are in flower. The daily pollen concentration decreases as the dry season progresses, accompanied by a change in composition; fewer herbaceous but increasing woody taxa. Preliminary health outcomes reveal a positive association between hay fever, Poaceae and Acacia pollen, as well as a significant association between total fungal spore concentrations and asthma. The Darwin record contrasts significantly with surveys conducted in the subtropical and temperate cities of Australia where temperature as opposed to rainfall and the prevalence of northern hemisphere exotic tree species have a greater influence over the seasonality and composition of the pollen loads.     

The diurnal variation of Poaceae pollen concentrations in a rural area

Records of Poaceae pollen concentration from three years of sampling in a rural area of West Wales have revealed distinctive circadian patterns of variation. Maximum pollen concentrations are typically recorded between 14.00 and 16.00 hours, on days both above and below an average daily Poaceae pollen count of 50 grains m^-3, although later peaks in concentration may be recorded during periods with no precipitation. Variations in the periodicity of Poaceae pollen are analysed in relation to meteorological conditions, phenological patterns of pollen release, pollen source area, and the magnitude of the average daily pollen count. The time of peak pollen concentration in West Wales is generally earlier than in other studies and this is explained by this study being conducted closer to Poaceae pollen source areas than most urban-based studies.     

A 2-year aeropalynological survey of allergenic pollen in the atmosphere of Kastamonu, Turkey

Knowledge of airborne pollen concentrations and the weather conditions influencing them is important for air quality forecasters, allergists and allergy sufferers. For this reason, a 7-day recording volumetric spore trap of the Hirst design was used for pollen monitoring between January 2006 and December 2007 in Kastamonu, Turkey. A total of 293,427 pollen grains belonging to 51 taxa were recorded during the study period. In the 2?years of study, the period March–August was identified as the main pollination season for Kastamonu. The highest monthly pollen counts were observed in May in both years. Six taxa made up 86.5% of the total amount of pollen recorded in the atmosphere of Kastamonu. These were as follows: Pinaceae (42.9%), Cupressaceae (20.6%), Poaceae (9.7%), Quercus (5.5%) Betula (5.3%) and Carpinus (2.6%). Four of these are considered to be highly allergenic (Betula, Carpinus, Cupressaceae and Poaceae). There were also a greater percentage of highly allergenic taxa found within the city, including Betula pendula that is not part of the local flora. This shows that through urban planting, the public and municipalities can unconsciously create a high risk for allergy sufferers. Daily average pollen counts from the six most frequently recorded pollen types were entered into Spearman’s correlation analysis with meteorological data. Mean daily temperature, relative humidity, daily rainfall and wind speed were found to significantly (p?<?0.05) affect atmospheric pollen concentrations, but the relationships between pollen concentrations and meteorological variables can vary and so there is a need for more local studies of this nature.     

Aprpaoches to airborne pollen in SE spain. First survey in murcia: one year of pollen monitoring (1993–94)

First data from a pollen survey carried out in the city of Murcia (SE Spain) are given in this paper. Using a Burkard Volumetric Spore Trap, daily slides were prepared and 80 pollen types belonging to 51 families andAlternaria spores were identified and counted. Special attention was paid to 14 relevant taxa: Cupressaceae,Pinus, Genisteae,Olea, Morus, Acer, Platanus, Plantago, Quercus, Urticaceae, Poaceae, Chenopodiaceae,Artemisia andAlternaria. The main sources of airborne particles wereAlternaria (27.7%), Cupressaceae (13.5%),Olea (9.36%), Chenopodiaceae (8.31%) and Urticaceae (5.8%). Annual variations in pollen abundance and length of the flowering seasons are given for individual species and are related to environmental factors. Results indicate a main pollen season from March to June and a second minor season in September to October. The relatively high concentrations of Genisteae and the appearance of anArtemisia winter season were noted.     

Comparison of airborne herb pollen types in Córdoba (Southwestern Spain) and Poznan (Western Poland)

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.     

Aerobiology of Artemisia airborne pollen in Murcia (SE Spain) and its relationship with weather variables: annual and intradiurnal variations for three different species. Wind vectors as a tool in determining pollen origin

Detailed results from a 2-year survey of airborne pollen concentrations of Artemisia in Murcia are presented. Three consecutive pollen seasons of Artemisia occurring each year, related to three different species (A. campestris, A. herba-alba and A. barrelieri), were observed. A winter blooming of Artemisia could explain the incidence of subsequent pollinosis in the Murcia area. With regard to meteorological parameters, mathematical analyses showed relationships between daily pollen concentrations of Artemisia in summer–autumn and precipitations that occurred 6–8 weeks before. The cumulative percentage of insolation from 1 March seemed to be related to blooming onsets. Once pollination has begun, meteorological factors do not seem to influence pollen concentrations significantly. Intradiurnal patterns of pollen concentrations were similar for late summer and winter species (A. campestris and A. barrelieri). During autumn blooming (A. herba-alba), the intradiurnal pattern was particularly erratic. Theoretical values of wind run were obtained for each pollen season by the graphical sum of hourly wind vectors. When theoretical wind run was mapped onto the vegetation pattern, supposed pollen source locations were obtained for each hour. By comparing supposed hourly pollen origins with the intradiurnal patterns of pollen concentrations, it can be seen that this simple model explains variations in mean pollen concentrations throughout the day. Received: 6 May 1998 / Revised: 24 February 1999 / Accepted: 12 March 1999     

Airborne pollen concentration in Ankara,Turkey 1990–1993

Atmospheric pollen was collected with a Burkard spore trap in Ankara, Turkey, from January 1990 to January 1993. A total of 135.787 grains/m³ belonging to 47 taxa were observed. The local pollen season started in February in 1990 and 1991 and in March in 1992. Relatively low pollen concentrations were recorded in 1990 and 1992, probably because of precipitation and low wind speed in the spring. A relatively high pollen concentration was recorded in 1991 which could be caused by higher wind speed in the spring and more precipitation during the winter. Cupressaceae/Taxaceae, Pinaceae, Gramineae, Betula, Moraceae, Platanus, Populus, Acer, Quercus, Chenopodiaceae/Amaranthaceae, Plantago, Rumex are found to be the dominant pollen types in the atmosphere in Ankara. The pollen composition generally reflects the vegetation of gardens, parks and roadsides, while the natural steppe vegetation of the area around Ankara is not properly represented.     

A 3-year airborne pollen and fungal spores record in San Carlos de Bariloche, Patagonia, Argentina

Airborne pollen in San Carlos de Bariloche was sampled from September to March 2001–2004 with a Hirst-type volumetric spore trap placed at a height of 15 m in a city extending from the humid forests, through the mesic forests, to the steppe. The total amount of pollen recorded varied widely from year to year. The pollen index was 4,395 in the sampling period 2001/2002; 9,055 in 2002/2003 and 2,756 in 2003/2004. The main pollen period extended from October to January. In October, pollen concentration was the highest. Sixty-six pollen types were identified. Cupressaceae and Nothofagus were the major contributors. Betula, Prunus, Pinus and Populus, the most abundant ornamental taxa in the city, also contributed to the pollen record. Pollen of Maytenus and Lomatia was representative of the mesic forest, while pollen in the lower layers of the humid forest was present in trace amounts. Cupressaceae, Nothofagus and Betula prevailed during spring (September–December), and Plantago, Rumex and Poaceae during summer (December–March). The association of daily pollen concentration and meteorological variables, temperature (mean, maximum, minimum), dew point, rainfall and wind speed, was significant. Correlations showed to be negative, with the exception of that to wind speed. The total sum of fungi spores increased from 1,771 in 2001/2002; through 8,441 in 2002/2003 to 13,782 in 2003/2004. Relative concentration rose to 29%, 48% and 84% of the total number of pollen and fungal spores recorded during each sampling period.     

Study of Poaceae phenology in a Mediterranean climate. Which species contribute most to airborne pollen counts?

The present study sought to determine which of the common Poaceae species in the study area contribute most to the Poaceae pollen season curve, and to determine the phenological behaviour of the species studied. The different floral phenophases in thirty-three Poaceae species common in and around the city of Córdoba (SW Iberian Peninsula) were checked periodically over the period 2004–2006. Results showed that longer phenological ranges were recorded in the coolest and wettest year, and shorter ranges in the warmest and driest year. Moreover, ranges varied as a function of altitude: populations in lower-lying areas flowered earlier than those at higher altitudes. The results, taken in conjunction with the findings of preliminary research into potential pollen production, showed that probably only four of the Poaceae species studied—Dactylis glomerata, Lolium rigidum, Trisetaria panicea and Vulpia geniculata—were major contributors to the Poaceae airborne pollen curve.