Earlier Flowering of Betula pendula Roth in Augsburg, Germany, Due to Higher Temperature, NO2 and Urbanity and Relationship with Betula spp. Pollen Season

Flowering and pollen seasons are sensitive to environmental variability and are considered climate change indicators. However, it has not been concluded to what extent flowering phenology is indeed reflected in airborne pollen season locally. The aim of this study was to investigate, for the commonly represented in temperate climates and with highly allergenic pollen Betula pendula Roth, the responsiveness of flowering to different environmental regimes and also to check for commensurate changes in the respective pollen seasons. The region of Augsburg, Bavaria, Germany, was initially screened for birch trees, which were geolocated at a radius of 25 km. Random trees across the city were then investigated during three full flowering years, 2015–2017. Flowering observations were made 3–7 times a week, from flower differentiation to flower desiccation, in a total of 43 plant individuals. Data were regressed against meteorological parameters and air pollutant levels in an attempt to identify the driving factors of flowering onset and offset. Flowering dates were compared with dates of the related airborne pollen seasons per taxon; airborne pollen monitoring took place daily using a Hirst-type volumetric sampler. The salient finding was that flowering occurred earlier during warmer years; it also started earlier at locations with higher urbanity, and peaked and ended earlier at sites with higher NO2 concentrations. Airborne pollen season of Betula spp. frequently did not coincide locally with the flowering period of Betula pendula: while flowering and pollen season were synchronized particularly in their onset, local flowering phenology alone could explain only 57.3% of the pollen season variability. This raises questions about the relationship between flowering times and airborne pollen seasons and on the rather underestimated role of the long-distance transport of pollen.

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Searching for a trace of Artemisia campestris pollen in the air

Acta Agrobotanica ◽

10.5586/aa.2015.040 ◽

2015 ◽

Vol 68 (4) ◽

pp. 399-404 ◽

Cited By ~ 3

Author(s):

Łukasz Grewling ◽

Idalia Kasprzyk ◽

Katarzyna Borycka ◽

Kazimiera Chłopek ◽

Łukasz Kostecki ◽

...

Keyword(s):

Pollen Season ◽

Airborne Pollen ◽

Rank Correlation ◽

Temporal Variations ◽

Monitoring Site ◽

Pollen Data ◽

Pollen Monitoring ◽

Bimodal Pattern ◽

Pollen Seasons ◽

Artemisia Campestris

The aim of the study was to determinate whether Artemisia campestris was present in the vicinity of 8 pollen monitoring stations in Poland by examining temporal variations in daily average airborne Artemisia pollen data recorded by Hirst type volumetric traps. Three day moving averages of airborne Artemisia pollen were examined by Spearman’s rank correlation test. Results show that Artemisia pollen seasons in Poland generally display similar unimodal patterns (correlation coefficients r > 0.900; P < 0.05). The only exception was the Artemisia pollen concentration noted in the outskirts of Poznań (Morasko), where the bimodal pattern was revealed. Correlations between Artemisia pollen data recorded at Poznań-Morasko and the other Polish sites were the lowest in the investigated dataset; this was particularly noticeable in the second part of pollen season (r ~0.730). We show that the typical bimodal pattern in Artemisia pollen seasons, which is characteristic of the presence of both A. vulgaris (first peak) and A. campestris (second peak), does not occur at the majority of sites in Poland and is restricted to the outskirts of Poznań. In fact, it was noted that the pollen monitoring site in Poznań-Centre, just 8 km from Morasko, only exhibited one peak (attributed to A. vulgaris). This shows that the influence of A. campestris on airborne pollen season curves is limited and can be largely disregarded. In addition, this study supports previous records showing that the spatial distribution of airborne Artemisia pollen within a city (urban-rural gradient) can vary markedly, depending on the species composition.

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Main features of Poaceae pollen season in Madeira region (Portugal)

Acta Agrobotanica ◽

10.5586/aa.2015.032 ◽

2015 ◽

Vol 68 (4) ◽

pp. 367-372

Author(s):

Irene Câmara Camacho ◽

Rita Câmara ◽

Roberto Camacho

Keyword(s):

Pollen Season ◽

Airborne Pollen ◽

Growing Season ◽

Onset Date ◽

Critical Levels ◽

Pollen Monitoring ◽

Madeira Island ◽

Poaceae Pollen ◽

The Mean ◽

Low Levels

The pollinic spectrum of the Madeira region is dominated by grass pollen, which also represents an important aeroallergen in Europe. The present work aims to analyze the main features of the Poaceae pollen season in the Madeira region to determine the allergic risk. The study took place in Funchal city, the capital of Madeira Island, over a period of 10 years (2003–2012). The airborne pollen monitoring was carried out with a Hirst type volumetric trap, following well-established guidelines.In the atmosphere of Funchal, the mean annual Poaceae pollen index was 229. The mean Poaceae pollen season lasts 275 days, with an onset date in January/March and an end date in November/December. Poaceae counts showed a seasonal variation with 2 distinct peaks: a higher peak between March and June, and the second one in autumn. The peak values occurred mainly between April and June, and the highest peak was 93 grains/m3, detected on the 27th May of 2010. The Poaceae pollen remaining at low levels during the whole growing season, presenting a nil to low allergenic risk during most of the study period. Higher critical levels of allergens have been revealed after 2006. In general, the pollen risk from Poaceae lasted only a few days per year, despite the very long pollen season and the abundance of grasses in the landscape of Madeira Island.

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50 Years of Pollen Monitoring in Basel (Switzerland) Demonstrate the Influence of Climate Change on Airborne Pollen

Frontiers in Allergy ◽

10.3389/falgy.2021.677159 ◽

2021 ◽

Vol 2 ◽

Author(s):

Regula Gehrig ◽

Bernard Clot

Keyword(s):

Climate Change ◽

Pollen Season ◽

Airborne Pollen ◽

Linear Trend ◽

Linear Increase ◽

Pollen Monitoring ◽

Pollen Species ◽

Poaceae Pollen ◽

Almost All ◽

Start Dates

Climate change and human impact on vegetation modify the timing and the intensity of the pollen season. The 50 years of pollen monitoring in Basel, Switzerland provide a unique opportunity to study long-term changes in pollen data. Since 1969, pollen monitoring has been carried out in Basel with a Hirst-type pollen trap. Pollen season parameters for start dates, end dates and duration were calculated with different pollen season definitions, which are commonly used in aerobiology. Intensity was analyzed by the annual pollen integral (APIn), peak value and the number of days above specific thresholds. Linear trends were calculated with the non-parametric Mann Kendall method with a Theil-Sen linear trend slope. During the last 50 years, linear increase of the monthly mean temperatures in Basel was 0.95–1.95°C in the 3 winter months, 2–3.7°C in spring months and 2.75–3.85°C in summer months. Due to this temperature increase, the start dates of the pollen season for most of the spring pollen species have advanced, from 7 days for Poaceae to 29 days for Taxus/Cupressaceae. End dates of the pollen season depend on the chosen pollen season definition. Negative trends predominate, i.e., the pollen season mostly ends earlier. Trends in the length of the pollen season depend even more on the season definitions and results are contradictory and often not significant. The intensity of the pollen season of almost all tree pollen taxa increased significantly, while the Poaceae pollen season did not change and the pollen season of herbs decreased, except for Urticaceae pollen. Climate change has a particular impact on the pollen season, but the definitions used for the pollen season parameters are crucial for the calculation of the trends. The most stable results were achieved with threshold definitions that indicate regular occurrence above certain concentrations. Percentage definitions are not recommended for trend studies when the annual pollen integral changed significantly.

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Flowering and airborne pollen - a novel statistical approach

Acta Agrobotanica ◽

10.5586/aa.2007.030 ◽

2012 ◽

Vol 60 (2) ◽

pp. 51-55 ◽

Cited By ~ 2

Author(s):

Idalia Kasprzyk ◽

Adam Walanus

Keyword(s):

Pollen Season ◽

Statistical Approach ◽

Airborne Pollen ◽

Pollen Grains ◽

Weather Conditions ◽

Time Pattern ◽

Se Poland ◽

Full Flowering ◽

High Concentrations ◽

Intensive Growth

The time pattern of flowering significantly affects the pollen season, its beginning, length and the concentration of pollen grains in air. The forecasting models used in aerobiological studies were chiefly based on the elements of weather conditions; however, recently the phenology of pollen shedding has been taken into consideration in these models more and more frequently. The aim of the presented investigations was to determine to what extent the flowering and the occurrence of allergenic pollen grains in air coincided in time. The investigation was carried out in Rzeszów (SE Poland) in the years 2003-2004. The flowering of 19 allergenic plant species was observed and seven phenophases were distinguished. Aerobiological monitoring was based on the volumetric method. In the case of most herbaceous plants, the flowering period overlapped the pollen season, high concentrations of pollen being recorded throughout several phenophases. In general, the pollen of trees occurred during very short periods, frequently during one phenophase, while the investigated phenomena were missing each other. The most intensive growth of inflorescences of alder, hazel and birch was observed at the beginning of full fl owering or towards the end of full flowering.

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The relationship between flowering phenology and pollen seasons of Alnus Miller

Acta Agrobotanica ◽

10.5586/aa.2012.058 ◽

2012 ◽

Vol 65 (2) ◽

pp. 57-66 ◽

Cited By ~ 3

Author(s):

Agnieszka Dąbrowska ◽

Bogusław Michał Kaszewski

Keyword(s):

Wind Speed ◽

Pollen Season ◽

Meteorological Factors ◽

Airborne Pollen ◽

Gravimetric Method ◽

Air Humidity ◽

Inflorescence Development ◽

Relative Air Humidity ◽

Pollen Seasons ◽

The Relationship

The dynamics of flowering and pollen release in anemophilous plants and the length of the particular phases depend largely on the geobotanical features of a region, its climate, meteorological factors, biological characteristics of vegetation, and abundance of pollen resources. The aim of the study was to determine the relationship between the flowering phases in eight Alnus taxa and the dynamics of occurrence and abundance of airborne pollen grains as well as the meteorological factors (maximum and minimum temperature, relative air humidity, maximum wind speed, and precipitation). The flowering phenophases and pollen seasons were studied in 2008–2011. Phenological observations of flowering were conducted in the Maria Curie-Skłodowska University Botanical Garden in Lublin and they involved the following taxa: Alnus crispa var. mollis, A. glutinosa, A. incana, A. incana ‘Aurea’, A. incana ‘Pendula’, A. maximowiczii, A. rubra and A. subcordata. Spearman’s r correlation coefficients were calculated in order to determine the relationship between the dynamics of inflorescence development and meteorological conditions. Aerobiological monitoring using the gravimetric method was employed in the determination of Alnus pollen content in the air. The annual phenological cycles in 2008-2011 varied distinctly in terms of the time of onset of successive flowering phases in the Alnus taxa studied, which depended largely on the taxonomic rank and meteorological factors. The following flowering sequence was revealed in the 2008-2011 growing seasons: A. subcordata (December or January), A. incana ‘Pendula’, A. incana, A. maximowiczii, A. rubra, A. glutinosa, A. incana ‘Aurea’ (February or March), and A. crispa var. mollis (April). The study demonstrated that the pollen of the taxa persisted in the air, on average, from mid-December to early May. The mean length of the flowering period, which coincided with various phases of the pollen season, was 17 days. The Alnus pollen season in 2008 started at the end of January and lasted until mid-March. In 2009, 2010, and 2011, the beginning of the pollen season was recorded in the first week of March and the end in the first week of April. The maximum concentration of airborne Alnus pollen was found at the full bloom stage of mainly A. glutinosa and A. rubra. Inflorescence development was most closely related to temperature and relative air humidity; there was a weaker relationship with wind speed and precipitation.

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Flowering Phenology of Selected Linden (Tilia L.) Taxa in Relation to Pollen Seasons

Journal of Apicultural Science ◽

10.1515/jas-2016-0030 ◽

2016 ◽

Vol 60 (2) ◽

pp. 193-208

Author(s):

Agnieszka Dąbrowska ◽

Krystyna Piotrowska-Weryszko ◽

Elżbieta Weryszko-Chmielewska ◽

Ryszard Sawicki

Keyword(s):

Pollen Season ◽

Airborne Pollen ◽

Average Length ◽

Pollen Grains ◽

Flowering Phenology ◽

Flowering Period ◽

Growing Seasons ◽

Time Period ◽

Relative Air Humidity ◽

Atmospheric Pollen

Abstract All lindens provide Apidae insects with nectar, pollen, and honeydew. Lindens are important melliferous trees in Poland. The first purpose of the study was to carry out phenological observations of the flowering in ten linden taxa. The second aim was to analyse the content of linden pollen grains in the air of Lublin. A correlation between the parameters of the pollen season and meteorological factors was also determined. This study was conducted in the city of Lublin located in the central-eastern part of Poland. The flowering phenophases were analysed, using the method developed by Łukasiewicz, during the growing seasons of 2012-2015. Aerobiological monitoring, which was based on the volumetric method, was carried out over the 2001-2014 time period. As shown in the study, the flowering period of all the analysed linden taxa lasted 7 weeks, on average, from June 7 to July 24. The average length of the flowering period of the investigated taxa and hybrids was in the range of 12-17 days. Their flowering periods overlapped. The atmospheric pollen season lasted, on average, from mid-June to the second 10-day period of July. The highest concentration of airborne pollen was noted at the end of June. The pollen season pattern was significantly affected by temperature and relative air humidity as well as by rainfall in May and June. The investigations indicate a 9-day acceleration of the pollen season, which may be associated with global warming.

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OLIVE YIELDS FORECASTS AND OIL PRICE TRENDS IN MEDITERRANEAN AREAS: A COMPREHENSIVE ANALYSIS OF THE LAST TWO DECADES

Experimental Agriculture ◽

10.1017/s0014479716000077 ◽

2016 ◽

Vol 53 (1) ◽

pp. 71-83 ◽

Cited By ~ 5

Author(s):

F. ORLANDI ◽

F. AGUILERA ◽

C. GALÁN ◽

M. MSALLEM ◽

M. FORNACIARI

Keyword(s):

Olive Oil ◽

Pollen Season ◽

Marketing Strategies ◽

Oil Price ◽

Pollen Monitoring ◽

Pollen Emission ◽

Full Flowering ◽

Market Situation ◽

Price Trends ◽

Olive Cultivation

SUMMARYThe main objective of this research was to utilize pollen monitoring methodology to predict olive yields in three Mediterranean olive cultivation areas (Spain, Italy and Tunisia) and their relationships with the olive oil price dynamics. Moreover, olive yield and olive oil production compared with olive oil price trends in the last two decades was evaluated. The statistical analyses confirmed that biological parameters such as the pollen emission, the pollen season start (Pss), the full flowering (Ff) date or the pollen season length (Psl) showed positive correlation values with productive parameters, especially the Pollen Index (Pi). However, the difficulty to define clear relationships with oil price for optimizing the marketing strategies can be due to the olive sector European policy and to the complex international olive oil market situation. The occurrence of unharvested trees was increased and the reduction in agricultural operations as well as non-harvesting could become more widespread above all in traditional extensive systems.

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Spatial differentiation of airborne arboreal pollen in Lublin (Poland)

Acta Agrobotanica ◽

10.5586/aa.2015.035 ◽

2015 ◽

Vol 68 (4) ◽

pp. 333-341

Author(s):

Krystyna Piotrowska-Weryszko ◽

Elżbieta Weryszko-Chmielewska

Keyword(s):

Airborne Pollen ◽

Spatial Differentiation ◽

Sampling Device ◽

Long Distance ◽

Pollen Monitoring ◽

Se Poland ◽

Long Distance Transport ◽

Arboreal Pollen ◽

Pollen Concentrations ◽

Positive Correlations

The study compared the occurrence of airborne pollen of 7 arboreal taxa (Corylus, Alnus, Cupressaceae/Taxaceae, Populus, Fraxinus, Betula and Carpinus) during the period 2007–2009 from two sites in Lublin city, SE Poland. The sites differed in the character of building development and surrounding vegetation. Pollen monitoring was conducted by the volumetric method using two Hirst-type samplers. Daily and intradiurnal pollen counts were determined. For all the taxa, Spearman’s test revealed statistically significant positive correlations between daily pollen fluctuations at two sites. Nevertheless, the Mann–Whitney U-test showed differences for Cupressaceae/Taxaceae, Fraxinus, Populus and Corylus between sites. The intradiurnal pattern of pollen concentration was characterized by high variation. Cupressaceae/Taxaceae and Populus, clearly differed in hourly pollen concentrations at both sites. Moreover, in the case of Betula and Alnus it was shown that a part of pollen recorded in Lublin can originate from long-distance transport. High pollen concentrations can be expected at different hours of the day. The lowest average pollen concentrations at both sites were found during morning hours at 5 and 6 a.m. Based on the obtained results, it can be concluded that data from a single pollen-sampling device are not representative of some taxa in the particular districts of the city. Average data obtained from at least two pollen samplers could provide optimum results.

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Ecological features of Ambrosia artemisiifolia L. flowers and characteristics of Ambrosia L. pollen seasons in the condition of Lublin (Poland) in the years 2001-2008

Acta Agrobotanica ◽

10.5586/aa.2008.031 ◽

2012 ◽

Vol 61 (2) ◽

pp. 35-47 ◽

Cited By ~ 5

Author(s):

Elżbieta Weryszko-Chmielewska ◽

Krystyna Piotrowska

Keyword(s):

Airborne Pollen ◽

Pollen Grains ◽

Mean Value ◽

Ambrosia Artemisiifolia ◽

Cultivated Plants ◽

Long Distance ◽

Long Distance Transport ◽

Ecological Features ◽

Pollen Seasons ◽

Male Flowers

In the study, the biology of fl owering of Ambrosia artemisiifolia L. was investigated and the pattern of the Ambrosia pollen seasons in Lublin in the years 2001-2008 was characterised. The structure of male and female A. artemisiifolia flowers was observed in cultivated plants under controlled conditions in the 2000 vegetative season. The number of pollen grains produced by the stamen, flower, inflorescence and plant was determined. It was shown that in A. artemisiifolia flowers nonfunctional pistils occurred with a reduced ovary, performing the role of a pollen presenter. The pistils found in female flowers differed significantly in their morphological features from the pistils in male flowers. It was calculated that one stamrn produced an average of 3 375 pollen grains, whereas one flower 16 875. A plant which produces 20 racemes may release over 420 million pollen grains into the atmosphere. The Ambrosia pollen seasons in particular years had different patterns. In some years, the days of maximum concentration were in the second half of August, in other years in the first half of September. Over the 8-year period, the maximum daily concentration had a mean value of 116 pollen grains in m3 (31-311). Annual total concentrations of Ambrosia pollen grains ranged between 194 and 1200 grains, and it was 523 grains on the average. The pollen seasons were characterised by the occurrence of several-day-long interruptions in the presence of airborne pollen in the atmosphere of Lublin, which may indicate the long-distance transport of Ambrosia pollen.

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The phenological phases of flowering and pollen seasons of spring flowering tree taxa against a background of meteorological conditions in Kraków, Poland

Acta Agrobotanica ◽

10.5586/aa.1678 ◽

2016 ◽

Vol 69 (2) ◽

Cited By ~ 2

Author(s):

Danuta Stępalska ◽

Dorota Myszkowska ◽

Katarzyna Piotrowicz ◽

Idalia Kasprzyk

Keyword(s):

Pollen Season ◽

Meteorological Data ◽

Corylus Avellana ◽

Meteorological Conditions ◽

Maximum Temperature ◽

Flowering Period ◽

Long Distance ◽

Pollen Concentrations ◽

Pollen Seasons ◽

Phenological Phases

The aim of the study was to compare phenological observations of pollen seasons of selected early spring trees. Special attention was paid to meteorological conditions which favored or did not favor tree flowering and pollen release. For this reason, we used phenological observation, pollen counts, and meteorological data in five sites in the center of Kraków in the period 2009–2011. Phenological phases (5) of four tree species: Alnus glutinosa, Alnus incana, Corylus avellana, and Betula pendula, were analyzed. It was found that in case of A. glutinosa the pollen season often preceded the flowering period, while for A. incana those two phenomena were more correlated. As regards Corylus avellana, the beginning of the pollen season and phenological phases was simultaneous. However, pollen grains occurred in the air longer, even by a dozen or so days. The phenological phases and pollen seasons of Alnus and Corylus were dependent on meteorological conditions. To give the definition of the relationship between pollen concentration and weather conditions, Spearman rank correlation analysis was applied. High Alnus and Corylus pollen concentrations were found on sunny days with a maximum temperature over 10°C and no precipitation, and when the snow cover was gone. In case of Betula, the phenological phases of the full pollination period usually coincided with the periods of high pollen concentrations. However, Betula pollen sometimes appears earlier and stays in the air longer than the flowering period of local trees in the nearest vicinity. This situation indicates long-distance transport or secondary deposition.

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