全 文 ：Received 23 Jun. 2003 Accepted 20 Dec. 2003
Supported by the Research Foundation of Zonguldak Karaelmas University (2001-13-03-11).
http://www.chineseplantscience.com
Acta Botanica Sinica
植 物 学 报 2004, 46 (6): 668-674
Airborne Pollen Grains in Zonguldak, Turkey, 2001-2002
Ayse KAPLAN
(Zonguldak Karaelmas University, Faculty of Science-Art, Department of Biology, Incivez, Zonguldak 67100, Turkey)
Abstract: The variation in airborne pollen concentration of the Zonguldak region, Turkey was studied for
two consecutive years 2001-2002 using a Durham sampler. During this period, a total of 61 304 pollen
grains belonging to 43 taxa were recorded. Of these 43 taxa, 26 belonged to arboreal and 17 to non-
arboreal plants. The main pollen types were Pinaceae, Populus, Carpinus, Betula, Corylus, Fagus orientalis,
Castanea sativa, Alnus glutinosa, Quercus, Cupressaceae, Chenopodiaceae and Gramineae, representing
96.7% of the pollen spectrum. Pollen concentration reached the highest level in March.
Key words: Turkey; Zonguldak; pollen; pollen calendar
Regional atmospheric pollen concentrations have rel-
evance in several situations, including agriculture (Cour
and Vancampo,1980; Norris-Hill, 1999; Rodriguez et al.,
2000), environmental assessment (Leuchner and Bohem,
1982; Bousquet et al., 1984; Speiksma et al., 1989; Cerceau-
Larrival et al., 1991; Speiksma and Nolard, 1991; Grandjouan
et al., 2000; D’Amato and Liccardi, 2003) and allergic dis-
eases (Banik and Chanda, 1992; D’Amato et al., 1998; Sin
et al., 2001). This fact has aroused a greater worldwide
interest in knowing the pollen content of the atmosphere of
towns and cities.
Knowledge of the local flora, native or introduced, en-
hances the probability of correctly identifying pollen grains
which can affect human health. There is evidence that the
prevalence of allergic diseases induced by pollen has in-
creased (D’Amato et al., 1998).
Weather conditions such as temperature, rainfall and
wind speed probably have an important influence on num-
bers of pollen grains in the atmosphere (Minero et al., 1999;
Rodriguez et al., 2000; Molina et al., 2001; Latalowa et al.,
2002; Green et al., 2003; Porsbjerg et al., 2003; Ribeiro et
al., 2003).
The aim of this study is to present the results of two
years (2001-2003) of continuous gravimetric sampling of
airborne pollen in the Zonguldak atmosphere, their per-
centage values, pollen season periods and pollen concen-
trations in relation to some climatic factors.
Fifty-two percent of the land of Zonguldak is forest,
48% is shrubbery, meadowy and pasture. The dominant
broad-leafed trees are Fagus orientalis (Oriental Beech),
Quercus (Oak), Carpinus betulus (Hornbeam), C. orientalis
(Oriental Beam), Castanea sativa (Chestnut), Platanus
orientalis (Oriental Plane), Tilia tomentosa (Silver Lime),
Alnus glutinosa (Common Alder), Corylus colurna (Turkish
Hazel) and Ostrya carpinifolia (Hop Hornbeam). These
species cover 70% of all forest. The dominant evergreen
trees are Abies nordmanniana (Caucasian Fir), Pinus brutia
(Red Pine), P. sylvestris (Scots Pine), P. nigra subsp.
pallasiana (Black Pine), P. pinaster (Maritime Pine) which
comprise 30% of all forest trees. The lands below the forest
limit consist of Rhododendron ponticum, Prunus
laurocerasus (Cherry Laurel), P. cerasus (Sour Cherry),
Cornus mas (Cornus), Erica arborea (Heather), Rosa canina
(Wild Rose), Arbutus unedo (Strawberry Tree), Rubus
sanctus, Fragaria vesca (Strawberry) Quercus ilex (Holm
Oak). Populus spp. (Poplar) and Salix sp. (Willow) are fre-
quently seen in the river-sides.
In coastal areas, Cistus creticus and C. salviifolius,
Hypericum calysinum, P. pinaster, Antirrhinum majus
(Snapdragon), Linaria genistifolia, Laurus nobilis (Laurel),
Arbutus unedo (Strawberry Tree) are widespread species.
In adition to natural vegetation of Zonguldak, the fol-
lowing species are frequently seen in the parks, gardens
and streets of the town: Acacia spp. (Wattle), Acer spp.
(Maple), Betula spp. (Birch), Catalpa bignonoides (Indian
bean Tree), Cedrus libani (Cedar of Lebanon), Cercis
siliquastrum (Judas Tree), Cornus mas (Cornus), Cupressus
sempervirens (Italian Cypress), Daphne laurolea (Spurge-
Laurel), Elaeagnus angustifolia (Oleaster), Fraxinus ex-
celsior (Common Ash), Forsytia spp., Juglans regia
(Walnut), Juniperus spp., Ligustrum vulgare (Ligustrum),
Magnolia spp., Morus alba (White Mulberry), Nerium ole-
ander , Olea europaea (Olive Tree), Pinus brutia (Red Pine),
P. pinaster, Populus tremula (Poplar), Prunus domestica
(Plum), Salix babylonica (Chinese Weeping Willow) and
Thuja spp.
Ayse KAPLAN: Airborne Pollen Grains in Zonguldak, Turkey, 2001-2002 669
1 Materials and Methods
Zonguldak is situated at 41.5° N, 31.8° E in Northwest
Turkey (Fig.1) at an altitude of 0-150 m above sea level.
Zonguldak has a Mediterranean, Euxin vegetation and gen-
erally an oceanic climate.
In this study, a gravimetric method and a Durham sam-
pler were used. The Durham sampler was placed on the
roof of an office, the roof being at height of 10 m above
ground level. Slides placed in the Durham sampler were
changed weekly. Before exposure, the slides were covered
with glycerine jelly mixed with basic fuchsin (Charpin and
Surinyach, 1974). The slides were examined weekly under
the light microscope. The identification and counting of
pollen grains were determined at least up to family, genus
and some to species levels. The numbers of pollen grains
found in the cover-glass area (24 mm× 50 mm) were
counted.
The meteorological data for Zonguldak were derived
from the records of the Government Meteorological Insti-
tute in Ankara.
2 Results
A total of 61 304 pollen grains from 43 taxa, 26 813 in
2001 and 34 491 in 2002, have been identified in the atmo-
sphere of Zonguldak during the two years. Out of 43 taxa,
26 were arboreal while the others were non-arboreal plants.
A total of 58 163 pollen grains have been found to be as
arboreal (94%), 3 141 as non-arboreal (6%) (Table 1).
The main pollen producers in the atmosphere of
Zonguldak were following arboreal plants: Pinaceae,
Populus, Carpinus, Betula, Corylus, Fagus orientalis,
Castanea sativa, Alnus glutinosa, Quercus, Cupressaceae.
They form 90% of the total pollen fall (Table 1). From herba-
ceous plants and shrubs, Gramineae, Chenopodiaceae,
Ambrosia, Erica, Plantago and Artemisia were found fre-
quently in the atmosphere of Zonguldak making up 4.5% of
the total.
Monthly variations of total pollen grains recorded in
the atmosphere of Zonguldak during the years 2001-2002
are shown in Fig. 2. The seasonal variation of arboreal and
non-arboreal pollen fall is given in Fig. 3.
Fig.1. Map of Turkey showing the location of Zonguldak.
Table 1 Annual totals of weekly pollen counts
Arboreal plants (AP) 2001 2002 Total Total%
Acer 79 80 159 0.30
Aesculus 5 0 5 0.01
Ailanthus 10 100 110 0.20
Alnus glutinosa 265 1 123 1 388 2.30
Betula 1 187 1 354 2 541 4.10
Carpinus 2 755 2 437 5 192 8.50
Castanea sativa 2 522 107 2 629 4.30
Citrus 10 6 16 0.03
Cornus 0 88 88 0.10
Corylus 833 2 581 3 414 5.60
Cupressus 667 771 1 438 2.40
Fagus orientalis 3 184 287 3 471 5.70
Juglans 524 244 768 1.30
Laurus nobilis 44 223 267 0.40
Moraceae 84 106 190 0.30
Oleaceae 579 231 810 1.30
Pinaceae 5 455 12 747 18 202 29.73
Platanus orientalis 332 242 574 0.90
Populus 4 191 8 848 13 039 21.30
Quercus 1 391 939 2 330 3.80
Robinia pseudoacacia 102 6 108 0.20
Rosa 16 29 45 0.10
Salix 36 50 86 0.10
Tilia 10 7 17 0.03
Ulmus 398 259 657 10.00
Total (AP) 24 679 32 865 57 544 94.00
Non-arboreal 2001 2002 Total Total%
plants (NAP)
Achillea 8 0 8 0.01
Ambrosia 113 189 302 0.50
Artemisia 24 73 97 0.12
Campanula 3 0 3 0.01
Carex 37 36 73 0.10
Chenopodiaceae 131 57 188 0.30
Cistus 0 21 21 0.03
Daucus 8 9 17 0.03
Erica 570 214 784 1.20
Gramineae 987 696 1 683 2.70
Lotus 0 102 102 0.17
Luzula 59 0 59 0.10
Plantago 122 49 171 0.28
Ranunculus 0 46 46 0.10
Rumex 50 57 107 0.18
Taraxacum 6 0 6 0.01
Urticaceae 0 77 77 0.13
Xanthium 16 0 16 0.03
Non-Arboreal 2 134 1 626 3 760 6.00
Plants (NAP)
Total (AP+NAP) 26 813 34 491 61 304 100.00
Acta Botanica Sinica 植物学报 Vol.46 No.6 2004670
The earliest pollen grains in the atmosphere of
Zonguldak were noted in January (Fig.4). The predominant
arboreal pollen grains were observed in this month (Corylus,
Cupressaceae, Pinaceae, Populus and Oleaceae). Pollen
grain concentrations began to increase in February and
reached their maximum values in March (Figs.2,3). Pinaceae,
Carpinus, Fagus orientalis, Betula, Quercus, and
Cupressaceae releasing high amounts of pollen into the
atmosphere throughout their pollination period, were re-
sponsible for more 90% of the total pollen in March.
Amounts of pollen grains were also at a high level in April,
May and June. The pollen grains of grasses and weeds
become dominant in July and August, but the amount of
pollen was lower than the springtime. This decrease was
correlated with the end of the pollination periods of many
arboreal plants which produced and released high amounts
of pollen grains into the atmosphere (Figs.2,3). In June,
Castanea sativa, Gramineae, Chenopodiaceae, Pinaceae and
Plantago were recorded as dominant taxa (Fig.4). In July,
Gramineae, Chenopodiaceae and Plantago were dominant.
In August Ambrosia, Artemisia, Lotus and Chenopodiaceae
prevailed; in September and October, Artemisia, Ambrosia
and Pinaceae; in November and December, Pinaceae were
noted as dominant.
The types of pollen present in the atmosphere of
Zonguldak are shown in the form of a pollen calendar (Fig.
4), based on the counts made in 2001-2002. The following
taxa produced the greatest amounts of pollen in the atmo-
sphere of Zonguldak.
Pinaceae Pollen grains were recorded during the greater
part of the year, from January to December. The pollen
season started in the second week of January and ended in
the last week of December (52nd week). The highest value
was noted in the last week of May (21st week).
Populus The pollen season started in the last week of
January (5th week) and ended in last week of April (17th
week). The pollen concentration reached its maximum level
in the third week of February (8th week).
Fagus orientalis The pollen grains were present dur-
ing 16 weeks. The pollen season started in the third week of
February (8th week) and ended in the second week of June
(24th week). The maximum pollen concentration was re-
corded in third week of March (12nd week).
Carpinus The pollen production was continued from
the last week of January to the last week of May (21st
week). The highest value was noted in the second week of
March (10th week).
Corylus The pollen grains were present during 13
weeks. The pollen season was started in the second week
of January (2nd week) and ended in the first week of May
(18th week). The maximum level was recorded in the last
week of January (5th week).
Castanea sativa The pollen season started in the last
week of May (22nd week) and ended in the second week of
July (28th week). The highest level was noted in the third
week of June (25th week).
Betula Pollen production was continued from the
third week of February to the third week of June (26th week).
The maximum value was recorded in the last week of Febru-
ary (9th week).
Quercus The pollen season was started in the last
week of February (9th week) and ended in the last week of
May (22nd week). The highest pollen concentration was
noted in the last week of March (12nd week).
Gramineae Pollen grains were recorded during 28
weeks, from the 9th week to the 39th week. The highest
count was recorded in the last week of May (22nd week).
The Gramineae family was the only herbaceous taxon dis-
persing high amount of pollen into atmosphere.
Alnus glutinosa Pollen production was continued
Fig.2. Monthly totals of atmospheric pollen in Zonguldak,
2001-2002.
Fig.3. Monthly variations of arboreal (AP) and non-arboreal
(NAP) pollen grains in Zonguldak, 2001-2002.
Ayse KAPLAN: Airborne Pollen Grains in Zonguldak, Turkey, 2001-2002 671
Fig.4. Pollen calendar of Zonguldak.
from the 5th week to the 14th week. The maximum pollen
concentrations were noted in the 6th and 7th weeks.
Cupressaceae The pollen season started in the 4th
week of January and ended in the third week of June (25th
week). The maximum value was recorded in the 4th week of
January.
Oleaceae Pollen grains of this family were noted from
5th week (the last week of January) to 23rd week (the first
week of June). The maximum count was noted in the third
week of March (12nd week).
Acta Botanica Sinica 植物学报 Vol.46 No.6 2004672
Juglans The pollen season started in the first week of
March (10th week) and ended in the last week of May (22nd
week). The highest value was noted in the first week of
April (14th week).
Platanus orientalis The pollen season started in the
third week of February (8th week) and culminated in the
last week of May (22nd week). The maximum level was re-
corded in the first week of April (14th week).
Erica Pollen production was continued from 9th week
(the last week of February) to 22nd week (the last week of
May). The highest value was noted in the 11st week (the
second week of March).
Ulmus The pollen season was relatively short. It started
in the first week of February (6th week) and culminated in
the first week of June (23rd week). The highest count was
recorded in the second week of March (11st week).
Ambrosia Pollen production was continued during 11
weeks, from 30th week to 41st week. The maximum pollen
concentration was noted in the last week of August (Fig.
4).
The correlation between the monthly pollen concentra-
tion and the monthly meteorological factors over the pe-
riod January 2001-January 2003 is shown in Fig.5.
In January and February, since the temperature and wind
speed were low, pollen counts were low. Low temperatures
dropped the pollen concentration (Minero et al., 1999;
Norris-Hill, 1999).
In March, there was a significant increase in the number
of pollen grains. This can also be correlated with greater
temperature and wind speed than the previous months.
Pollen concentrations in April were very different from
those in March. There was an important decrease in pollen
concentration occurred in April 2002. The heavy rain in
April 2002 (61.6 mm) and lower wind speed (5.7 m/s) low-
ered the pollen amount. There was also seen a small decline
in pollen concentration in April 2001. This can be explained
the fact that the wind speed and the temperature were lower
than in March 2001 (Fig.5).
Pollen concentration continued to decrease in May 2001
but, increased in May 2002. Higher rainfall (173 mm) and
lower wind speed (4.8 m/s) reduced pollen concentration in
May 2001, but the lower rainfall (47.4 mm) and the higher
wind speed (7.0 m/s) increased pollen concentration in May
2002.
In June 2001, the increase in the total pollen amount was
caused by the beginning of the pollination of herbs and the
maximum pollen dispersal of Castanea sativa (Chestnut)
and Gramineae. The high temperature (19.9 oC) and high
wind speed (6.3 m/s) raised the pollen counts. In addition,
rainfall during in May 2001 (173 mm) increased the flower-
ing intensity (McDonald, 1980).
Unlike in June 2001, in June 2002 the lower wind speed
(5.2 m/s) and the higher rainfall (84.5 mm) caused a decline
in pollen concentration of Castanea sativa and the others.
The lower pollen concentration in July is attributed to
the decline in pollen production by trees at the end of the
flowering season rather than weather conditions.
There was a small increase in pollen concentration of
herbs in August (Fig.5). The higher temperature and the
higher wind speed raised pollen amounts of herbs. In
September, October, November and December the very low
values of airborne pollen were recorded due to the higher
rainfall and the lower temperature than those in August.
Fig.5. Monthly variations in atmospheric pollen and weather
conditions in the atmosphere of Zonguldak from 1 January, 2001
to 1 January, 2003.
Ayse KAPLAN: Airborne Pollen Grains in Zonguldak, Turkey, 2001-2002 673
3 Discussion
In the atmosphere of Zonguldak, arboreal pollen types
were dominant; this is due to the character of vegetation
and geographical location of the town. The important tree
pollen types were Pinaceae, Populus, Betula, Corylus,
Alnus glutinosa, Carpinus, Juglans, Fagus orientalis,
Quercus and Castanea sativa. Grass pollen appeared with
a maximum flowering period from the end of April to the end
of September and overall maximum value at the beginning
of June. The herb pollen season was recorded from the
third week of January until the second week of November.
The highest herb pollen peak was recorded from the begin-
ning of June to the beginning of October when
Chenopodiaceae, Artemisia, Ambrosia and Plantago were
very abundant in the atmosphere.
According to the main pollination period of the various
types recorded, three groups could be distinguished: (1)
pollen with a short principal period <10 weeks: Acer,
Achillea, Aesculus, Ailanthus, Castanea sativa, Cistus,
Citrus, Cornus, Daucus, Laurus nobilis, Lotus, Luzula,
Ranunculus, Taraxacum, Tilia and Xanthium; (2) pollen
with a medium principal period, between 10 and 15 weeks:
Alnus glutinosa, Ambrosia, Artemisia, Carpinus, Carex,
Cornus, Corylus, Erica, Juglans, Platanus orientalis,
Populus, Quercus, Robinia pseudoacacia, Rumex, Rosa,
Salix, Ulmus, Urtica; and (3) pollen with along principal
period, >15 weeks: Betula, Chenopodiaceae, Cupressaceae,
Fagus orientalis, Gramineae, Morus, Oleaceae and Pinaceae.
The correlation between the monthly airborne pollen
counts and the monthly meteorological factors over the
period January 2001-January 2003 clearly showed that the
pollen concentration was effected by all meteorological
parameters (wind speed, temperature and rainfall).
The lower pollen concentration in 2001 can be attrib-
uted to high rainfall (173 mm in May) and low temperature
(12.5 oC in May) in spring. High and continuous rainfall
depressed pollen dispersal (McDonald, 1980; Norris-Hill,
1999; Ribeiro et al., 2003). In addition, the lower wind speed
(4.8 m/sec in May) slowed down pollen dispersal in the
atmosphere (McDonald, 1980; Tsou et al., 1997; Molina et
al., 2003).
The higher numbers of pollen in the air samples in 2002
is attributed to greater wind speed, lower rainfall and higher
temperature in spring than that in 2001. The mean wind
speed in spring of 2002 was 7.0 m/s while it was 6.0 m/s in
spring of 2001. The mean temperature in spring of 2002 was
15 oC while it was 13 oC in spring of 2001. Another reason
for the greater amount of pollen in 2002 is higher precipita-
tion during December 2001 (266 mm) and January 2002 (115
mm) than in December 2000 (200 mm) and January 2001 (97
mm). Storage of water in the soil during the winter caused
plant growth and increased flowering intensity in spring
(McDonald 1980).
Seasonal totals of weekly concentrations for grass pol-
len were higher in 2001 (987 grains/12 cm2) than in 2002 (696
grains/12 cm2). This was probably caused by the higher
wind speed in June 2001 (6.3 m/s) than in June 2002 (5.2 m/
s). McDonald (1980) has showed that wind velocity has
the greatest influence on the numbers of grass pollen in the
atmosphere.
Some important allergenic pollen grains such as Pinaceae,
Gramineae, Populus, Carpinus, Betula, Platanus, Quercus,
Cupressaceae, and Chenopodiaceae were also found in high
concentrations. These pollen types are responsible for many
cases of pollinosis (Banik and Chanda, 1992; Kosiski and
Carpenter, 1997; Hallsdottir, 1999; Nitiu and Mallo, 2002).
The pollen calendar for the region presented in this pa-
per may be useful for allergologist to establish an exact
diagnosis.
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