Seasonal distribution of pollen in the atmosphere of melbourne: an airborne pollen calendar

Environmental monitoring of pollen grains in the atmosphere of Melbourne has been achieved using Burkard volumetric traps. Twenty-two families of flowering plants and confiers were identified in the pollen counts. About 62% of these pollen grains belonged to trees, 20% to grasses and 9% to herbs and weedy plants. During spring and summer, the atmosphere contained about 70% of the total annual pollen count. Tree pollen, predominantly elm and cypress, occurred abundantly in late winter and spring, with grass pollen predominantly in spring and early summer. These three types of pollen grains occurred in significant amounts, together accounting for more than 60% of the total annual catch. A seasonal incidence chart (pollen calendar) for Melbourne based on 2 years observation has been constructed. This pollen calendar is useful in identifying sources of allergies against particular seasonal airborne pollen types. Comparison of the time of occurrence of a particular pollen type using the pollen calendar and the time of allergic symptoms, can lead to accurate diagnosis and preventive measures being taken. This study has confirmed that grass pollen is the major source of allergenic pollen in the external environment triggering hay fever and allergic asthma in spring and early summer in Melbourne, Australia.     

Incidence of Echium pollen in the Middle West of Iberian Peninsula: an unusual flowering period and its significance in aerobiological studies

We analysed the occurrence of the Echium pollen in the atmosphere of Salamanca, on the basis of 8-year observation (2000–2007) with the aim to evaluate its aerobiological behaviour. Aerobiological samples were collected by the Hirst volumetric method with a 7-day Burkard spore trap. The atmospheric pollen season of Echium was observed in late spring (May and June), showing also high levels in midday hours. However, an anomalous flowering period was detected in late autumn and early winter between years 2006 and 2007 and it could be connected with high daily temperature registered in October 2006 in comparison with the 2000–2005 period and its particular increasing tendency similar to those detected in the preceding month of the late spring flowering period. Statistical analysis by means of the Spearman’s non-parametrical test and linear regression analysis reflected a positive correlation with temperature and a trend to increase in daily temperature during late October 2006 and April in 2000–2005 with similar indexes (R ²?=?0.50, R ²?=?0.58, respectively). In conclusion, aerobiological data could contribute to the development of further studies in order to a better understanding of different plant species phenology.     

A three year (1993–1995) calendar of pollen and Alternaria mould in the atmosphere of south western Sydney

The relevance of allergy skin prick testing in the diagnosis and treatment of seasonal allergic rhinitis and pollen asthma can usefully be interpreted in relation to the timing and duration of seasonal symptoms and the presence of pollen and mould spores in the air. This calendar has been constructed from three years continuous observations of pollen and Alternaria mould spore counts between January 1993 and December 1995, using a Burkard 7‐day volumetric spore trap. Of the total airborne pollen, tree pollen comprises 65%, weeds and herbs 11% and grasses 18%. Unidentified pollen, “other”; group, accounts for 6% of the total airborne pollen. The most numerous of the tree pollen is that of the introduced trees cypress (Cupressus spp.) and privet (Ligustrum spp.). Grass pollen is seen in small numbers throughout the winter but shows a rapid increase in spring to peak in mid to late November. Weeds pollinate from early spring through to summer. Alternaria mould, which is a risk factor for childhood asthma, occurs mainly in late spring and summer but is present in small numbers intermittently throughout winter.     

Airborne pollen of Brisbane,Australia: A five-year record, 1994 - 1999

The seasonal incidence of pollen in the atmosphere of Brisbane has been established from a near-continuous, volumetric trapping program over the five-year period, July 1994-June 1999. Grass pollen accounts for 71.6% of the average annual pollen load with highest densities (up to 150 grains/m 3 ) recorded in summer and autumn. Significant contributions were also made by taxa of the Cupressaceae (8.7%) and Urticaceae (1.8%) during spring and of the Pinaceae (4.5%) during winter. Pollen seasons of the Casuarinaceae (6.5%) and Myrtaceae (3.2%) are more extended, the former peaking in late winter and the latter in late spring. The onset and duration of the Poaceae and Urticaceae seasons varied from year to year, being later when precipitation levels were low in the late spring-early summer months. Total pollen numbers and grass pollen densities are substantially less than those recorded from southern Australia. Nevertheless, respiratory disease in Brisbane affects up to 10% of the population, and airborne pollen of Poaceae, Urticaceae, Cupressaceae, Pinaceae, and Myrtaceae have been implicated in the release of allergens.     

Comparative study of the effect of distance on the daily and hourly pollen counts in a city in the south-western Iberian Peninsula

The airborne pollen concentration in the city of Badajoz was measured in two locations 2.9 km apart. The measurements were taken from January to June between 2009 and 2012 using Hirst-type volumetric aerobiological samplers. One sampler was placed at the Faculty of Science (FS) and the other at the Agricultural Engineering School (AES) of the University of Extremadura, Spain, on terraces located 16 and 6 m above ground, respectively. The two sets of hourly and daily pollen concentrations were compared regarding the meteorological parameters and the distribution of local pollen sources. A total of 46 pollen types were counted, with a mean total concentration of 43 pollen grains/m³ in the winter and 336 pollen grains/m³ in the spring. In the winter, pollen grains from (in decreasing order) Cupressaceae, Fraxinus–Phillyrea, Urticaceae spp., Alnus glutinosa and Urtica membranacea types represented 77 % of the total. In the spring, 89 % of the total was represented by pollen grains from (in decreasing order) Quercus, Poaceae, Olea, Pinaceae and Plantago. The FS/AES ratio was 0.57 in the winter and 1.31 in the spring. While a Wilcoxon test applied to the daily total concentration data showed statistically significant differences between the two sites, a correlation study based on the Spearman coefficient showed statistically significant correlations in both the winter and spring. The results were similar when comparing the separate pollen types, except for Urticaceae spp., which showed no statistically significant correlation. The meteorological data studied showed a statistically significant correlation with the daily concentrations. A comparison of the hourly concentration data showed no correspondence with the time of maximum concentration. The local distribution of pollen sources explained some of the differences found between the two sites. Overall, the results indicate that a single aerobiological sampler may be sufficiently representative to register the daily pollen grain data of an urban area of approximately 3 km or greater in diameter, although it underestimates the influence of heterogeneity in the distribution of the local flora.     

Pollen diversity in the atmosphere of Havana,Cuba

With a view to obtaining fuller information on airborne pollen content in the city of Havana, pollen sampling was carried out using a volumetric capture method, for the first time in Cuba. The study was conducted during 2 years (2011 and 2015). An annual pollen integral of 3414 grains was registered during the first year of study, whereas 5120 grains were observed along the 2015. Monthly maximum concentrations were recorded during April, June and July with total values close to 800 pollen grains. Of the 45 pollen types identified, Cecropia (38% of the total pollen identified in both years), Poaceae (18%), Urera type (9%) and Casuarina (6%) were particularly abundant. Although the main pollen types differed in terms of intradiurnal distribution, the highest concentrations were in all cases recorded between 0900 and 1300 hours. Maximum temperature was the variable most influencing airborne pollen counts in the air, with the exception of Casuarina. This paper sought to establish a methodological basis for the further development of aerobiological research in Cuba, thus helping to enhance the prevention and diagnosis of pollen allergies in the affected island population.     

Pollen spectrum in Northern Tunis,Tunisia

This study has been focused on airborne pollen concentration in Northern Tunis. Pollen has been detected by a volumetric Hirst-type spore trap. This suction sampler was placed for two hydrologic years in the area of Mornag, northeastof Tunisia (36°40N; 10°17E). Fifty-two taxa were identified with heterogeneous daily pollen concentrations and a dominance of anemophilous plants. The main pollen types detected in the atmosphere were Olea europaea (38.7 and 20.75%), Cupressus (33.57 and 55.4%), Urticaceae (9.22 and 12.24%), Poaceae (3.55 and 3.32%), Mercurialis annua (2.96 and 1.6%) and Amaranthaceae (2.49 and 1.55%). The monthly pollen spectrum indicated a seasonal periodicity of airborne pollen with the main pollen season during spring. Two pollen seasons have been observed during these hydrologic years, due to both Cupressus and Amaranthaceae airborne pollen is represented during winter or spring, and also during autumn and late summer, respectively. Other pollen types represent a long pollen season, i.e., Urticaceae, starting in autumn and following until late spring. Daily pollen concentration showed a different behavior during the flowering season between both years, observing differences related to pollen index. Correlation between daily pollen concentrations of the dominant taxa showed a positive and significant correlation between airborne pollen concentrations of spring-pollinated taxa and mean temperature, but negative with maximum temperature, humidity and rainfall. In the case of minimum temperature, a different response, positive for trees and negative for herbaceous plants, has been observed.     

First aerobiological study in Mediterranean part of Croatia (Dalmatia): pollen spectrum and seasonal dynamics in the air of Split

The aim of this study was to investigate aerobiological dynamics of pollen in the Mediterranean part of Croatia in the air of the city of Split. Pollen monitoring during the period from 2005 to 2013 was performed using a Hirst volumetric trap. Among the identified pollen of 50 taxa, 21 were allergenic. The average annual pollen index was 33,513. Three pollination seasons were established: early winter season dominated by tree pollen, spring–summer season dominated by herbaceous plants and summer–autumn season with lower amounts of Parietaria and Cupressaceae pollen. According to the abundance, the main taxa were: Cupressaceae, Parietaria/Urtica, Pinus, Quercus, Olea, Carpinus/Ostrya, Poaceae, Platanus and Ambrosia. The annual pollen index together with the daily maximum concentrations showed an upward trend for selected taxa during the study period. The highest monthly pollen index and the highest biodiversity were recorded in April and the lowest during the late autumn and winter months. The pollen calendar created for the city of Split confirmed Mediterranean features of the pollen spectrum. The longest pollen seasons were recorded for Cupressaceae, Parietaria/Urtica and Poaceae pollen types. The correlations between pollen concentrations and meteorological parameters were analyzed. The correlations between pollen concentrations and temperature were positive, while the humidity and the precipitation mostly showed negative influence.     

Seasonal fluctuations of the airborne pollen spectrum in Murcia (SE Spain)

During six consecutive years (1993–1998), aBurkard volumetric pollen trap was continuouslyoperated to sample pollen from the air of thecity of Murcia. The aim of the study was toelucidate the spectra of airborne pollen andthe variations during the year, and toelaborate a pollen calendar. This time spanincludes the end of the period with severedrought from 1990–1995, which particularly affected the south-eastern region of Spain.The total sum of daily average pollenconcentrations amounted to 148,645 pollen grainsbelonging to 93 different taxa. A daily averageof 74 pollen grains/m³ and 11 taxa wererecorded, with maxima of 1157 and 27respectively. The total pollen amountregistered in a year correlated with yearlyrainfall, but there was no relation with meanannual temperature. As for annual fluctuations,there seemed to be no influence by totalrainfall or temperature. Spring and winter werethe seasons with the highest pollen counts andpollen diversity.From the 93 identified taxa, 36 are included inthe pollen calendar. Noteworthy findings are:(i) the presence of Thymelaeaceae,Robinia, Betula, Castanea,Zygophyllum, Caryophyllaceae andCannabis, (ii) a long pollen season ofChenopodiaceae/Amaranthaceae, Urticaceae,Poaceae, Arecaceae and Plantago, (iii)the occurrence of summer, autumn and winterflowering of Artemisia, (iv) the lateappearance of Corylus pollen, and (v) theminor presence of Casuarina pollen duringthe mid winter and late spring.     

Airborne Ericaceae Pollen Grains in the Atmosphere of Vigo (Northwest Spain) and Its Relationship with Meteorological Factors

Several species of the Erica genus are broadly represented in northwest Spain, being among the shrubs that form the substitution stage following forest degradation as a result of human activity, caused mainly by fire or other antrophic causes. Therefore airborne pollen from Erica is frequent. From 1995 to 2002,an aerobiological study of Ericaceae family pollen was undertaken in the atmosphere of the city of Vigo (Northwest Spain) using a Lanzoni VPPS 2000 (Lanzoni srl, Bologna, Italy) sampler placed in the left margin of the Vigo fiord (42°14′15″ N, 8°43′30" W). Despite being a taxon of eminently entomophillous pollination,the pollen of Ericaceae was well represented in the atmosphere above the study zone. Erica arborea L. is the main species represented in the annual pollen curve. This taxon shows a long main pollen season and higher pollen concentrations were recorded during the months of April and May, which is why beekeepers place their beehives at specific locations in April to ensure a considerable contribution from this pollen to the composition of the honey. The maximum daily average concentration was detected in 1997, with a concentration of 156 grains/m3. Throughout the day, maximum values occur at 5/6 h and between 17:00 and 18:00 h. Finally, correlation statistical analyses were developed in order to determine the degree of association between the daily average of meteorological parameters and daily mean airborne pollen concentrations.Rainfall exerts a clear influence on Ericaceae pollen season characteristics, with precipitation registered in March being responsible for the decrease in total annual pollen values.     

Airborne Ericaceae Pollen Grains in the Atmosphere of Vigo （Northwest Spain） and Its Relationship with Meteorological Factors

Abstract: Several species of the Erica genus are broadly represented in northwest Spain, being among the shrubs that form the substitution stage following forest degradation as a result of human activity, caused mainly by fire or other antrophic causes. Therefore airborne pollen from Erica is frequent. From 1995 to 2002, an aerobiological study of Ericaceae family pollen was undertaken in the atmosphere of the city of Vigo (Northwest Spain) using a Lanzoni VPPS 2000 (Lanzoni srl, Bologna, Italy) sampler placed in the left margin of the Vigo fiord (42°14'15 "N, 8°43'30" W). Despite being a taxon of eminently entomophillous pollination, the pollen of Ericaceae was well represented in the atmosphere above the study zone. Erica arborea L. is the main species represented in the annual pollen curve. This taxon shows a long main pollen season and higher pollen concentrations were recorded during the months of April and May, which is why beekeepers place their beehives at specific locations in April to ensure a considerable contribution from this pollen to the composition of the honey. The maximum daily average concentration was detected in 1997, with a concentration of 156 grains/m³. Throughout the day, maximum values occur at 5/6 h and between 17:00 and 18:00 h. Finally, correlation statistical analyses were developed in order to determine the degree of association between the daily average of meteorological parameters and daily mean airborne pollen concentrations. Rainfall exerts a clear influence on Ericaceae pollen season characteristics, with precipitation registered in March being responsible for the decrease in total annual pollen values.
(Managing editor: Ya-Qin HAN)     

6. Peat-bog Begbunar (Osogovo Mountains,south-west Bulgaria): Four millennia of vegetation history

The aim of this study was to estimate the polleniferous potential of the most common plant communities and crops across the landscape through the study of pollen loads collected by Apis mellifera. We analysed pollen load samples from hives located in Mallorca (western Mediterranean) for one year and compared the results with a phytosociological study of the foraging area. We also analysed meteorological data to evaluate the influence of some environmental factors on the pollen production phenology. We identified 74 different pollen types (66.2% from native flora, 25.7% from exotic flora, and 8.1% from crops) belonging to 33 families. The highest polleniferous potentials in the landscape were attained by sclerophyllous forests (Quercetea ilicis) in spring, crops in autumn, wild annual rangelands (Stellarietea mediae) in winter and gardens in late summer. Our results suggest that the higher the coverage present in a vegetation class, the higher the quantity and diversity of pollen that may be provided to pollinators; therefore, its polleniferous potential may be higher. Some meteorological conditions (rainfall, temperature and daily hours of sunlight) may affect this potential through their influence on flowering phenology.     

Aerobiology of Urticaceae pollen in Trieste (NE Italy)

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.     

北京城区气传花粉季节分布特征

研究北京城区气传花粉种类、数量及季节消长规律,为防治花粉症及建设合理城市绿地提供有效资料.应用Burkard采样器于2010年12月31日至2011年12月31日对北京城区气传花粉浓度进行监测,并对花粉浓度进行统计学分析.研究结果显示,2011年北京城区的花粉季节从3月20日起始,至10月18日截止,持续213d,占全年天数的58％;全年花粉含量月分布呈现两个高峰,第1个高峰为3-4月,主要花粉为木犀科、杨属、柳属等树木花粉,占全年花粉总量的30％;第2个高峰为8-9月,主要花粉为菊科、藜科及苋科等莠草花粉,占全年花粉总量的50％;2011年度北京城区最具代表性的气传花粉来自于菊科,比重占了收集到气传花粉的35％.研究结果还表明,秋季的气传花粉致敏性强,所以北京花粉症的高发季节主要集中在秋季,以8-9月为最高,其中有95％的病人在此期间出现花粉症症状.花粉浓度及飘散规律受当地植被状况及气候等多种因素影响,因此,北京城区空气中气传花粉飘散种类、数量及季节分布规律的调查结果,可以为本地区花粉症防治及绿化品种的选择提供可靠依据.     

Airborne pollen parameters and their relationship with meteorological variables in NE Iberian Peninsula

The present study explores the role of the meteorological variability in the pollen production and the timing of the airborne pollen season by analysis of the correlation between precipitation, insolation and temperature and the main standardised airborne pollen parameters of 22 taxa collected at 6 localities in Catalonia (NE Spain). The pollen parameters included in the study were: Annual Pollen Integral and the Start, End and Length of the Main Pollen Season. Considering that the Main Pollen Season of most of the taxa in Catalonia lasts from spring to summer or autumn, correlations between the pollen parameters and winter (from December to March) values of meteorological variables were calculated. Correlations between Monthly Pollen Integral and monthly values of the meteorological variables were also calculated. The results obtained report the synchronism registered in the variations of pollen concentration with precipitation (negative), insolation (positive) and temperature (positive). Temperature was the meteorological variable that showed a greater influence in the pollen production and the timing of the pollen season, being insolation the least one. The Start of the Main Pollen Season was the pollen parameter more correlated with the meteorological variables, especially with winter temperatures.     

A 10-year survey of allergenic airborne pollen in the city of Porto (Portugal)

Airborne pollen calendars are useful to estimate the flowering season of the different plants as well as to indicate the allergenic potential present in the atmosphere at a given time. In this study, it is presented a 10-year survey of the atmospheric concentration of allergenic pollen types. Airborne pollen was performed, from 2003 to 2012, using a 7-day Hirst-type volumetric trap. The interannual variation of the daily mean concentration of the number of pollen grains and the main pollen season was determined as well as the hourly variations and correlation with meteorological parameters. During the study period, 18 different allergenic pollen types were considered based on its representativeness on the total annual airborne pollen concentration. The lowest annual concentrations were sampled in 2006 and the highest in 2007. The highest airborne pollen concentration was found during early spring and early summer. On the contrary, December was the month with the lowest pollen concentration. The major pollen sampled belongs to trees followed by weeds and grasses, being the most representative pollen types in the atmosphere: Urticaceae, Platanus, Poaceae, Pinaceae, Cupressaceae, Acer, Quercus, Castanea, Plantago, Alnus, Olea europaea, Betula, Myrtaceae and Populus. Intradiurnal distribution patterns of the pollen types studied presented differences with some taxa being predominantly sampled in the morning (9–11 a.m.) while others in first night hours (between 9 and 12 p.m.). Significantly correlations were found between the airborne pollen concentration and meteorological parameters.     

Dynamics and behaviour of airborne Quercus pollen in central Iberian Peninsula

Quercus pollen is one of the most abundant pollen types in the atmosphere of central Iberian Peninsula (Spain), as a consequence of the extensive representation of well-preserved forests and shrub communities dominated by species of the genus Quercus in this area. This paper analysed key features of the Quercus pollination season in the central Iberian Peninsula and the influence of weather-related variables on airborne Quercus pollen concentration through statistical techniques of correlation analysis and the use of a decision tree model for predicting pollen concentrations. Quercus species are very common in Spain and Portugal, dominating a number of ecosystems including Mediterranean forests. This gives rise to very high airborne Quercus pollen concentrations, particularly in spring. Sampling was carried out over a 6-year period using a Hirst volumetric sampler, and the sampling procedure established by the Spanish Aerobiology Network. Results show that between 92 and 98.5 % of total annual airborne Quercus pollen was recorded in the April–June period. Annual pollen index were high in all study years, averaging 12,344 grains, but it should be highlighted that pollen production was highly variable between years. Correlations between mean daily Quercus pollen concentration and weather-related variables showed that in the pre-peak period, a significant positive correlation was observed with the mean daily temperature and the hours of sunshine and a negative correlation was observed with the humidity and the rainfall. In the post-peak period, a significant negative correlation was found with the mean daily temperature and the hours of sunshine. The predictions obtained in the decision tree model showed a moderate significant correlation (r = 0.42) with the daily Quercus pollen concentration predicted and the one observed. Temperature is the most influential variable in the release of Quercus pollen.     

陕西中部黄土高原地区空气花粉组成及其与气候因子的关系——以洛川县下黑木沟村为例

空气花粉研究是现代孢粉学、植被变迁与预测的重要内容之一.陕西省黄土高原地区洛川县2007-2009连续2a的空气花粉分析表明:空气花粉组成与区域植被分布特征和植物花期一致.与2007—2008年相比,2008-2009年的花粉总通量及蒿属花粉通量明显增加,但木本植物花粉通量降低,这主要与2008-2009年降水明显偏少密切相关.2007-2008年降雨量高于500 mm,花粉组合中乔木花粉百分比高于30％,表现出森林植被特点;2008-2009年降雨量少于450 mm,花粉组合中草本花粉高于80％,乔木花粉低于10％,更多表现出草原植被特点.但从植被观测来看并没有明显的变化,表明花粉组合较植被对气候变化更为敏感.主要花粉类型与气候因子的相关分析表明:气候因子影响空气花粉的组成及数量.栎属、松属、蔷薇科花粉数量主要受春季温度影响,温度越高花粉数量越多;其他季节花粉数量主要受相对湿度影响,湿度越低,花粉数量越大.榆属花粉数量主要与冬季温度有关,温度越高,花粉数量越高.杨属只受春季温度影响,春季温度越低,花粉数量越多.胡颓子科花粉含量主要受春季相对湿度、风速影响,相对湿度越低,风速越大,花粉数量越多.绝大多数草本花粉数量均主要受春、冬季相对湿度及风速影响,相对湿度越低,风速越大,花粉数量越高;此外,禾本科花粉数量还受春季温度影响,温度越高,花粉数量越多;菊科花粉数量在夏秋季节还受温度、湿度和风速的共同影响,温度越低,湿度越低,风速越大,花粉数量越多.这些结果表明,黄土高原中部地区的空气花粉特征能反映区域植被组成,且对气候变化非常敏感,对认识和预测当地气候变化与植被动态等具有重要意义.     

北京主要气传致敏花粉年浓度峰值日期预测

花粉是我国北方引发过敏性鼻炎最主要过敏原,花粉症发病期与花粉浓度高峰期吻合。基于北京地区2012至2020年花粉季多站、逐日分类花粉浓度观测数据分析,得出北京地区花粉浓度在3月上旬至5月中旬(可进一步划分为3月中旬至4月上旬和4月下旬至5月上旬两个高峰期)和8月中旬至9月中旬分别存在两个高峰期,第一个高峰期内优势致敏花粉种类为柏科、杨柳科和松科,第二个高峰期内优势致敏花粉种类为桑科、菊科蒿属和藜科。根据优势致敏花粉年浓度峰值日期观测数据,使用与花粉采样站点位置相匹配的逐日气象观测数据累积值,基于作物模型概念和模糊逻辑原理建立了北京地区主要气传致敏花粉年浓度峰值日期预测模型。经检验,柏科、杨柳科、松科、桑科、菊科蒿属和藜科花粉模型预测准确率分别为87.8%、80.0%、64.4%、86.7%、78.8%和81.8%。基于北京地区主要气传致敏花粉年浓度峰值日期预测模型可为本地花粉症防治提供理论参考。