Poaceae pollen in the atmosphere of Zagreb (Croatia), 2002 – 2005

Pollen of grasses (Poaceae) is one of the most important airborne allergen sources worldwide. The aim of the study was to determine diurnal, day‐to‐day, weekly, monthly and annual pollen variation, and the effect of selected meteorological parameters on atmospheric pollen concentrations in Zagreb. A preliminary study was carried out during four seasons (2002 – 2005), using a 7‐day VPPS 2000 Hirst volumetric pollen trap. Total annual grass pollen concentrations in Zagreb were constant (2 673 – 3 074 p.g.m^?3), with a relative drop in 2004 (1 196 p.g.m^?3). The beginning of the grass pollen season is usually observed when the average daily temperature exceeds 13.5°C (max. daily temp. 19.5°C), without precipitation. In all four study years the absolute peak of concentrations occurs in the second half of May. The length of pollen season during the study period was 157 – 173 days. A high variability was observed in the maximal concentration and in the number of days when grass pollen concentration exceeded the threshold value of 30 p.g.m^?3 (9 – 40 days). Statistically significant correlations were found between airborne grass pollen concentrations and air temperature, level of precipitation and relative humidity.     

Poaceae pollen in the air depending on the thermal conditions

The relationship between the meteorological elements, especially the thermal conditions and the Poaceae pollen appearance in the air, were analysed as a basis to construct a useful model predicting the grass season start. Poaceae pollen concentrations were monitored in 1991–2012 in Kraków using the volumetric method. Cumulative temperature and effective cumulative temperature significantly influenced the season start in this period. The strongest correlation was seen as the sum of mean daily temperature amplitudes from April 1 to April 14, with mean daily temperature >15 °C and effective cumulative temperature >3 °C during that period. The proposed model, based on multiple regression, explained 57 % of variation of the Poaceae season starts in 1991–2010. When cumulative mean daily temperature increased by 10 °C, the season start was accelerated by 1 day. The input of the interaction between these two independent variables into the factor regression model caused the increase in goodness of model fitting. In 2011 the season started 5 days earlier in comparison with the predicted value, while in 2012 the season start was observed 2 days later compared to the predicted day. Depending on the value of mean daily temperature from March 18th to the 31st and the sum of mean daily temperature amplitudes from April 1st to the 14th, the grass pollen seasons were divided into five groups referring to the time of season start occurrence, whereby the early and moderate season starts were the most frequent in the studied period and they were especially related to mean daily temperature in the second half of March.     

Effect of meteorological parameters on Poaceae pollen in the atmosphere of Tetouan (NW Morocco)

Poaceae pollen is one of the most prevalent aeroallergens causing allergenic reactions. The aim of this study was to characterise the grass pollen season in Tetouan during the years 2008–2010, to analyse the effect of some meteorological parameters on the incidence of the airborne Poaceae pollen, and to establish forecasting variables for daily pollen concentrations. Aerobiological sampling was undertaken over three seasons using the volumetric method. The pollen season started in April and showed the highest pollen index in May and June, when the maximum temperature ranged from 23 to 27 °C, respectively. The annual pollen score recorded varied from year to year between 2,588 and 5,404. The main pollen season lasted 114–173 days, with peak days occurring mainly in May; the highest concentration reached 308 pollen grains/m³. Air temperature was the most important meteorological parameter and correlated positively to daily pollen concentration increase. An increase in relative humidity and precipitation was usually related to a decrease in airborne pollen content. External validation of the models performed using data from 2011 showed that Poaceae pollen concentration can be highly predicted (64.2–78.6 %) from the maximum temperature, its mean concentration for the same day in other years, and its concentration recorded on the previous day. Sensitive patients suffering allergy to Poaceae pollen are at moderate to highest risk of manifesting allergic symptoms to grass pollen over 33–42 days. The results obtained provide new information on the quantitative contribution of the Poaceae pollen to the airborne pollen of Tetouan and on its temporal distribution. Airborne pollen can be surveyed and forecast in order to warn the atopic population.     

Frost periods and beginning of the ash (Fraxinus excelsior L.) pollen season in Basel (Switzerland)

In order to be able to forecast the beginning of the ash pollen season, several meteorological factors have been considered. During these research activities it appeared that the ash pollen release is closely linked to frost periods happening during the months of February and March. For 24 years over a period of 29 consecutive years, a daily concentration of 30 ash pollen grains/m³/day has been reached when the cumulated mean daily temperatures starting on the last day when the absolute minimum temperature is lower or equal to −2 °C amounts on average to 214 °C – admitting a variation of plus or minus 42 °C. As for the five remaining years, rain is three times responsible for the delay of the pollen release. This revised version was published online in June 2006 with corrections to the Cover Date.     

Temperature-induced excess mortality in Moscow,Russia

After considering the observed long-term trends in average monthly temperatures distribution in Moscow, the authors evaluated how acute mortality responded to changes in daily average, minimum and maximum temperatures throughout the year, and identified vulnerable population groups, by age and causes of death. A plot of the basic mortality–temperature relationship indicated that this relationship was V-shaped with the minimum around 18°C. Each 1°C increment of average daily temperature above 18°C resulted in an increase in deaths from all non-accidental causes by 2.8%, from coronary heart disease by 2.7%, from cerebrovascular diseases by 4.7%, and from respiratory diseases by 8.7%, with a lag of 0 or 1 day. Each 1°C drop of average daily temperature from +18°C to −10°C resulted in an increase in deaths from all non-accidental causes by 0.49%, from coronary heart disease by 0.57%, from cerebrovascular diseases by 0.78%, and from respiratory diseases by 1.5%, with lags of maximum association varying from 3 days for non-accidental mortality to 6 days for cerebrovascular mortality. In the age group 75+ years, corresponding risks were consistently higher by 13–30%. The authors also estimated the increase in non-accidental deaths against the variation of daily temperatures. For each 1°C increase of variation of temperature throughout the day, mortality increased by 0.3–1.9%, depending on other assumptions of the model.     

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.     

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.     

Modulation of Rubisco activity in leaves of <Emphasis Type="Italic">Prosopis juliflora</Emphasis> in response to tropical conditions in north India

The success of P. juliflora, an evergreen woody species has been largely attributed to temperature acclimation and stomatal control of photosynthesis under wide range of environmental conditions prevalent in India. We studied the contribution of the enzyme ribulose-1,5 bisphosphate carboxylase/oxygenase (Rubisco) in diurnal and seasonal photosynthesis changes in P. juliflora. The changes observed in photosynthesis under natural conditions could be effected by the growth temperatures, which ranged from 10–30 °C in winter to 30–47 °C in summer. However, the Total Rubisco activity displayed a constant diurnal pattern and showed a maximum at 1200 in all seasons namely spring, summer, monsoon and winter irrespective of the changes in temperature. The Total Rubisco activity from two cohorts of leaves produced in spring and monsoon appeared to be down-regulated differentially at low PPFD during the evening. The in vivo and in vitro measurements of carboxylation efficiency of Rubisco showed wide variation during the day and were correlated with the photosynthesis rate. The light activation of Rubisco showed the acclimation to moderately high temperatures in different seasons except in summer. The exceptionally high temperatures (>45 °C) in summer, though not affecting Total activity, severely inhibited the light activation of Rubisco and also modulated the recovery process for the activation of Rubisco. Our studies suggest that the modulation of Rubisco driven by Rubisco activase and not Rubisco per se was crucial for the diurnal regulation of photosynthesis. NBRI Publication No.: 528     

Ambrosia pollen in the air of Lublin, Poland

Studies on Ambrosia pollen concentrations were carried out in Lublin in the period 1995–2004. The effects of a number of meteorological factors were analysed. In the first period of the study, the gravimetric method was used (1995–1999), while in the second period, the volumetric method was applied. The results show an increasing trend in the amount of airborne pollen. The Ambrosia pollen season in Lublin lasts from August to October. Over a period of 5 years, the highest number of pollen grains was recorded in September (53%), followed by August (44%) and October (3%). There were wide variations in annual totals. The annual total pollen counts was 167–1180 grains, with the peak value in 2002. Maximum daily pollen concentrations (56–312 pollen grains m⁻³) were recorded in the first half of August and in the first half of September. On the days when high Ambrosia pollen concentrations occurred, the temperature was above 21°C and the winds were mainly from the southeast, south and east. Maximum intradiurnal concentrations of pollen grains occurred in the afternoon hours. These results indicate, to some degree, that Ambrosia pollen is transported for long distances before descent.     

Poaceae pollen in the atmosphere of Aranjuez,Madrid and Toledo (central Spain)

The main aim of this work is to study the aerobiological behaviour of Poaceae pollen in three areas of central Spain (Aranjuez, Madrid and Toledo), all of which are similar from a geographical, climatic and biogeographical point of view, and they are located nearby one another. The samplings were carried out over a period of 4 years (2005–2008) using Hirst-type spore traps. Grass pollen is responsible for most spring allergic reactions in the pollen-sensitive population in central Spain, and they are very abundant in the atmosphere of this part of Iberian Peninsula. The average amount of this pollen type, as a percentage of the annual total pollen amount, is 7.4% in Aranjuez, 9.2% in Madrid and 11.3% in Toledo. Poaceae pollen is present in the atmosphere over a long period of time (February–October), and its maximum concentrations are detected during May and June (weeks 16–25). The city of Toledo has the highest annual concentrations of grass pollen (average 5,797 grains) with a great number of days exceeding the allergy thresholds proposed by the Spanish Aerobiology Network (REA). Madrid and Aranjuez present similar annual concentrations of grass pollen with values of 2,961 grains and 2,751 grains, respectively. The correlation analysis between the daily levels of grass pollen and meteorological variables of temperature and rainfall show a significant correlation, positive with temperature (maximum, mean and minimum) and negative with rainfall.     

Thermal biology of the Central Asian blunt-nosed viper (Macrovipera lebetina turanica) from Nuratau Crest and the Chernov blunt-nosed viper (Macrovipera lebetina černovi) from Western Kysylkum

The ecology of the Central Asian blunt-nosed viper (Macrovipera lebetina turanica) inhabiting the Nuratau Crest of Uzbekistan is described. The temperature conditions of the environment and the spatialtemporal structure of the viper activity are represented, which made it possible to find some of thermobiological characteristics. The temperature diapason of full activity of this viper constitutes approximately 17–34°C. The temperature of thermostabilization is in the range of 26–31°C, nocturnal temperatures are elevated from 9–15°C to 18–23°C in spring and summer, respectively, and diurnal body temperatures are decreased from 18–22°C to 10–15°C. Feeding and digestion are normal in blunt-nosed vipers at 25°C, which is below the diurnal temperature variation. In spring, the light phase duration is rapidly increased from 3–6 h to 14 h or more. This length of time and the large diurnal variation in the body temperature from 18°C to 20–22°C facilitate active and efficient coupling. Later, the diurnal body temperature is decreased to 13–18°C, which facilitates successful recovery in males and pregnancy in females. Plots for the average viper body temperature in different seasons are represented. The thermobiological characteristics of the bluntnosed viper of Macrovipera lebetina ěrnovi are similar to M. l. turanica.     

Study of the pollen emissions of Urticaceae, Plantaginaceae and Poaceae at five sites in western Spain

A comparative study is presented of the pollen emissions of Urticaceae, Plantaginaceae and Poaceae, collected during 1995 with Hirst samplers (Burkard or Lanzoni) at five sites in western Spain: two Mediterranean sites located in the south (Huelva and Seville) and three Atlantic sites in the north (Orense, Vigo and Santiago). The annual pollen of Poaceae and Plantaginaceae collected in the Atlantic cities was found to be twice that in the Mediterranean sites, and the total amount of Urticaceae was higher at sites with an urban environment and subject to sea influence (Vigo, Huelva and Seville). At all the sites, the start of the main pollination periods (MPP) took place in the following order: Urticaceae, Plantaginaceae and Poaceae. It was also observed that the MPP of these three pollen types began earlier in Huelva and Seville, where the mean temperatures necessary for the beginning of pollen emissions are recorded very early. Regarding the variation in pollen concentrations throughout the year, Urticaceae presented peaks of maximum concentration in March (Huelva, Seville, Vigo and Orense) and June (Santiago); Plantaginaceae in March (south) and June (north); and Poaceae in May (south) and June–July (north). At northern sites, pollen emissions of Urticaceae and Plantaginaceae continued throughout the summer, while in the south they decreased considerably from May onwards. From the allergenic point of view, the indices of reactivity described for Urticaceae and Poaceae were exceeded more often at northern sites, in particular at Vigo. The meteorological conditions associated with periods of highest pollen emission of these three herbaceous types are a rise in mean temperature, light or absent rainfall, and abundant sunshine. The statistical correlations between pollen emissions and meteorological factors were not well-defined, either for the stations or for all the taxa, although they were clearer for the Atlantic cities and for Urticaceae.     

Temperature profiles of cellular growth and exopolysaccharide synthesis by Botryococus braunii Kütz. UC 58

Temperature profiles (range 20–33 °C) were obtained for growth and exopolysaccharide (EPS) biosynthesis of the microalga Botryococcus braunii strain UC 58 under photoautotrophic conditions. The maximum temperature for growth was 32 °C and the temperature dependence of the specific growth rate was described by the Hinshelwood equation based on the Arrhenius relationship. The optimal range of temperatures for growth and extracellular EPS synthesis (25–30 °C) concurred and production of 4.5–5 g l⁻¹ of EPS was obtained routinely, leading to high broth viscosities. Below 23 °C EPS biosynthesis was negligible, although the specific growth rate maintained high values. At supraoptimal temperatures EPS biosynthesis decreased, accompanying the increase in doubling time. The polymers formed at temperatures within the optimal range for production, when dissolved in water, produced solutions (2 gl⁻¹) with the highest viscosity, suggesting that their molecular weight showed the highest values. The degree of polymerization of the EPS synthesized at suboptimal and supraoptimal temperatures was significantly below the values within the optimal range.     

Poaceae pollen in the atmosphere of Tetouan (NW Morocco): effect of meteorological parameters and forecast of daily pollen concentration

The Poaceae pollen season has been characterized in Tetouan during a 7-year period, and the effect of weather conditions on daily concentrations was examined. The forecast models were produced using a stepwise multiple regression analyses. Firstly, three models were constructed to predict daily Poaceae pollen concentrations during the main pollen season, as well as the pre-peak and post-peak periods with data from 2008 to 2012 and tested on data from 2013 and 2014. Secondly, the regression models using leave-one-out cross-validation were produced with data obtained during 2008–2014 taking into account meteorological parameters and mean pollen concentrations of the same day in other years. The duration of the season ranged from 70 days in 2009 to 158 days in 2012. The highest amount of Poaceae pollen was detected in spring and the first fortnight of July. The annual sum of airborne Poaceae pollen concentrations varied between 2100 and 6251. The peak of anthesis was recorded in May in six of the other years studied. The regression models accounted for 36.3–85.7% of variance in daily Poaceae pollen concentrations. The models fitted best when the mean pollen concentration of the same day in other years was added to meteorological variables, and explained 78.4–85.7% of variance of the daily pollen changes. When the year 2014 was used for validating the models, the lowest root-mean-square errors values were found between the observed and estimated data (around 13). The reasonable predictor variables were the mean pollen concentration of the same day in other years, mean temperature, precipitations, and maximum relative humidity.     

Thermoregulation of alpacas bred in Italy

The present study monitored daily and seasonal variations of rectal temperature in response to different environmental temperatures in alpacas bred in the Italian Apennines at 300 m a.s.l. In each season, the rectal temperature of 33 clinically healthy alpacas was measured three times/day (morning, midday, afternoon). Ambient temperatures were also recorded. Rectal temperatures ranged from a minimum value of 35.1 to a maximum of 39.4°C, with a maximum daily thermal excursion (ΔT_rec) of 3.2°C. Temperatures increased throughout the day, with highly significant differences recorded in both young and adult animals between all the time bands (P < 0.001). These differences were particularly dramatic for adults in summer, when the mean rectal temperature in the morning was 36.3 ± 0.13°C, probably as a consequence of recent shearing. Significant ΔT_rec differences were recorded depending on the season in both young and adult animals (P < 0.001), with the highest ΔT_rec values recorded in summer (although the highest daily ambient excursion value was recorded in winter). In conclusion, similarly to alpacas bred in their natural environment, alpacas bred in Italy show a wide thermal neutrality zone, which is probably an adaptive response, that allows the animals to save energy. In the Italian Apennines, in order to prevent situations of hypothermia, with possible detrimental effects on alpacas’ health and welfare, shearing should be carried out only in warm seasons.     

Poaceae pollen concentrations in the atmosphere of three inland Croatian sites (2003-2004)

The aim of the study was to determine the length of Poaceae pollen season, intradiurnal, daily and monthly pollen variation, and the effect of some meteorological parameters on atmospheric pollen concentration, at three monitoring sites in inland Croatia during the 2003-2004 period. Seven-day Hirst volumetric pollen and spore traps were used for pollen sampling. At all three monitoring sites considerably higher precipitation and lower average temperature in 2004 led to a marked decrease in the grass pollen concentration in the air at all three monitoring sites. The highest grass pollen concentrations were recorded in Ivani? Grad (typical rural area), considerably lower in Samobor (effect of forest vegetation), and lowest in Zagreb (urban area). The highest atmospheric Poaceae pollen concentrations in inland Croatia were generally recorded in May and June. The highest intradiurnal concentrations were recorded between 8.00 and 12.00 a.m. Results of this aeropalynologic study are expected to help in preventing the symptoms of allergic reaction in individuals with Poaceae pollen hypersensitivity.     

Study onPlatanus hispanica Miller pollen content in the air of Seville, southern Spain

The work was carried out using a Cour trap that sampled the air of the city for 8 consecutive years (1987–1994). The pollen ofPlatanus hispanica is the fourth most abundant in the air of Seville (a mean of 11.05% of the total pollen collected). The variation throughout the years in the sum of weekly concentrations ofPlatanus hispanica pollen presents a certain biennial rhythm, in which years of high and low collection of pollen alternate. The starting day of the main pollination period (MPP) is negatively related with the mean of the mean temperatures for February (r=0.73,r ²=0.53,P=0.0398) and is earlier (at the beginning of March) when the mean temperature for February is high, and vice versa. The pattern of pollen variation inPlatanus hispanica remains constant through the years—pollen appears abruptly in high weekly concentrations (> 150 grains/m³) in March (sporadically at the beginning of April), with a week of maximum pollen emission (WMPE) in which more than 50% of the annual pollen is collected (in 6 of the 8 years), and a main pollination period (MPP) of 2 or 3 weeks (except in 1989 when it was 5 weeks). In every year (except 1989), weekly mean temperatures increased during the MPP, the duration of which depends on mean temperature and mean rainfall: mean temperatures > 16°C and absence of rainfall shorten the MPP, while lower temperatures and presence of rainfall lengthen it. The meteorological conditions most often found during the WMPE are mean temperatures > 15°C and rainfall absent or almost so.     

Influences of Culture Temperature on the Growth, Lipid Content and Fatty Acid Composition of Aurantiochytrium sp. Strain mh0186

The growth, lipid content, and fatty acid composition of Aurantiochytrium sp. strain mh0186 at different temperatures were investigated. Strain mh0186 grew well at 15–30°C, but weakly at 10°C. The biomass at 15–30°C was significantly higher than at 10 and 35°C, and the total lipid at 15–35°C was significantly higher than that at 10°C. The amount of DHA in the total fatty acid was highest at 10°C and decreased in response to temperature increase. The content of DHA (mg/g-dry cell weight) at 15–30°C were significantly higher than those at 35°C and those at 15–25°C were significantly higher than those at 10 and 35°C. The DHA yield at 15–35°C was significantly higher than those at 10 and 35°C. Unsaturation of fatty acid was regulated by temperature and was enhanced in response to temperature decrease. The ratio of DHA to DPA varied at different temperatures.     

Sand and nest temperatures and an estimate of hatchling sex ratio from the Heron Island green turtle (Chelonia mydas) rookery, Southern Great Barrier Reef

Sand and nest temperatures were monitored during the 2002–2003 nesting season of the green turtle, Chelonia mydas, at Heron Island, Great Barrier Reef, Australia. Sand temperatures increased from ∼ 24°C early in the season to 27–29°C in the middle, before decreasing again. Beach orientation affected sand temperature at nest depth throughout the season; the north facing beach remained 0.7°C warmer than the east, which was 0.9°C warmer than the south, but monitored nest temperatures were similar across all beaches. Sand temperature at 100 cm depth was cooler than at 40 cm early in the season, but this reversed at the end. Nest temperatures increased 2–4°C above sand temperatures during the later half of incubation due to metabolic heating. Hatchling sex ratio inferred from nest temperature profiles indicated a strong female bias.     

Variations in Quercus sp. pollen seasons (1996–2011) in Poznań, Poland,in relation to meteorological parameters

The aim of this study is to supply detailed information about oak (Quercus sp.) pollen seasons in Poznań, Poland, based on a 16-year aerobiological data series (1996–2011). The pollen data were collected using a volumetric spore trap of the Hirst design located in Poznań city center. The limits of the pollen seasons were calculated using the 95 % method. The influence of meteorological parameters on temporal variations in airborne pollen was examined using correlation analysis. Start and end dates of oak pollen seasons in Poznań varied markedly from year-to-year (14 and 17 days, respectively). Most of the pollen grains (around 75 % of the seasonal pollen index) were recorded within the first 2 weeks of the pollen season. The tenfold variation was observed between the least and the most intensive pollen seasons. These fluctuations were significantly related to the variation in the sum of rain during the period second fortnight of March to first fortnight of April the year before pollination (r = 0.799; p < 0.001). During the analyzing period, a significant advance in oak pollen season start dates was observed (?0.55 day/year; p = 0.021), which was linked with an increase in the mean temperature during the second half of March and first half of April (+0.2 °C; p = 0.014). Daily average oak pollen counts correlated positively with mean and maximum daily temperatures, and negatively with daily rainfall and daily mean relative humidity.