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1.
The aim of the study was to characterise Artemisia pollen season types according to weather conditions in Wroc?aw (south-western Poland) in the years 2002–2011. Over the period analysed, the start date of the pollen season (determined by the 95 % method) ranged from 10 July 2002 to 28 July 2010. The start date of the pollen season can be determined by using Crop Heat Units (CHUs). During the period 2002–2011, the Artemisia pollen season started after the cumulative value of CHUs had reached 2,000–2,100 °C. The three distinguished types of Artemisia pollen season are best described by the frequency of weather types defined by the type of circulation, mean daily air temperature, and the occurrence of rain. The variation in these factors affected the dynamics of the pollen season. The noteworthy frequency of days with rain and high seasonal sum of precipitation totals as well as the dominance of cyclonic weather from the westerly direction had an impact on the extension of the pollen season. The meteorological factors that directly affect pollen release and transport primarily include air humidity, expressed as vapour pressure (r > 0.3, p < 0.01), temperature(r from 0.2 to 0.4, p < 0.01). The relationships between averaged meteorological data and daily pollen concentration were stronger (r > 0.5, p < 0.01). Based on the correlation analysis, the meteorological variables were selected and regression equations were established using stepwise backward regression analysis.  相似文献   

2.
The airborne pollen concentration of the four mostfrequent and most allergenic taxa in Poland; Alnus, Betula, Poaceae, and Artemisia atPozna in the years 1995–1996 has been analyzed,using a Hirst-type volumetric spore trap. Theappearance of the earliest pollen producing taxa wasobserved as early as January and February, which isrelevant information for people subject to allergiesin the Pozna region, where Spring usually beginsin March. The periods of high and very high pollenconcentration of individual taxa have been comparedfor the two years.  相似文献   

3.
The aim of the work was to compare the alder pollen seasons in the years 1997–2017 in Sosnowiec. The measurements of pollen concentration were taken with the volumetric method using Burkard’s apparatus. The impact of atmospheric conditions on the daily alder pollen grain concentration, the annual totals, and the duration of pollen seasons were studied. The dependency between each meteorological condition and different features of the alder pollen season was determined by using Pearson’s correlation coefficients, variance analysis with multiple comparison tests, and the linear regression model using backward elimination. It was proven that the temperatures directly preceding the pollination, i.e. the January and February temperatures as well as those from the period from 210 to 180 days preceding the beginning of the season, have the greatest impact on the beginning of the alder pollen season. The value of the daily alder pollen concentration in Sosnowiec showed a positive statistically significant correlation with the air temperature and sunshine duration and a negative correlation with the thickness of the snow cover and air relative humidity. The daily concentration also depended on the type of the weather front, direction of air mass inflow, and the type of the inflowing air mass. The season temperatures and the thermal conditions which were present in the summer of the preceding year impacted the annual totals (SPI) of the alder pollen grains.  相似文献   

4.
The aim of the study was to compare the courseof flowering and the occurrence of Alnus,Corylus and Betula pollen grains inthe air in 1999–2001. In 2000 and 2001 birchesflowered in a typical way – the floweringperiod was short and intense and that periodhad the highest concentration of pollen. Bothyears had no rainfall then and the temperaturewas high, which caused intense flowering ofbirches over a large area. In 1999 and 2000most of the Alnus and Coryluspollen was recorded at the end or after theirflowering period. At that time the weather wasunstable (as is usual in February and March).Pollen must have been transported fromelsewhere. Wind analysis showed that the mainsources of Corylus pollen must have beenin the south, and of Alnus in the southand west. In the southern margin of Poland thevegetative period begins later due to a colderclimate.  相似文献   

5.
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.  相似文献   

6.
I. Kasprzyk 《Aerobiologia》2004,20(4):217-222
Airborne pollen of entomophilous plants occurred in low or very low concentrations, and constituted 4 of the total pollen sum. In 1997–2002, between 18 and 26 taxa were identified. Out of this large group the following taxa were represented in larger concentrations every year– Salix, Acer, Morus, Cichorioideae, Asterioideae, Plantago major/media, Sambucus nigra and Tilia. Microscopic examination revealed that pollen grains of the above mentioned species were often glued together, which is a typical adaptation to this kind of pollination. Club moss (Lycopodium spp.) and horsetail (Equisetum spp.) spores were recorded sporadically. Fern spores were found frequently but in very low numbers. In 2002 the occurrence of the airborne pollen of entomophilous plants in the city and in the countryside was compared. A higher percentage value of pollen was found in the atmosphere of the city rather than in the countryside, due to the high concentration of Acer pollen, which is a partly entomophilous species and common in municipal plantings. In the countryside air there was a higher concentration of pollen from purely entomophilous species, such as Viburnum and Asteroideae.  相似文献   

7.
The aim of this study was to confirm a presumptive qualification of clinical B. fragilis group strains isolated in P?ock as ESBL-positive strains and to determine some properties of these strains. Twenty four clinical strains belonging to the B. fragilis group, isolated first of all from surgical patients, were received for testing. Identification of strains was performed in the automatic ATB Expression system (bioMerieux sa, France) using biochemical API 20 A strips. Strains were tested for the production of catalase (ID Color Catalase test, bioMerieux sa) and beta-lactamase (Cefinase, BBL, Becton Dickinson, USA). Susceptibility of strains to four antimicrobial agents: clindamycin, metronidazole, amoxicillin/clavulanic acid and imipenem was determined by Etest (AB Biodisk, Sweden). ESBLs were detected with the use of two disc diffusion methods: the double-disc synergy test (DDST) according to Jarlier et al. and the diagnostic disc (DD) test according to Appleton. Seventeen of examined strains belonged to the species Bacteroides fragilis, three--to B. ovatus/thetaiotaomicron, two--to B. distasonis, one--to B. uniformis and one--to B. stercoris/eggerthii. One strain (B. uniformis) did not produce catalase, whereas all strains produced beta-lactamases. Examined strains were susceptible in vitro to metronidazole, amoxicillin/clavulanic acid and imipenem. One clindamycin-resistant strain was detected (B. fragilis). Occurrence of ESBL-type enzymes was confirmed in 22 strains of following species: B. fragilis (17 strains), B. ovatus/thetaiotaomicron (3), B. distasonis (1) and B. uniformis (1). Clinical strains of the B. fragilis group with a new mechanism of resistance to beta-lactam antibiotics appeared during last years in Poland. They produce extended-spectrum beta-lactamases (ESBLs), so they are resistant to penicillins, cephalosporins and monobactams. Monitoring of infections caused by these threatening strains in hospital patients is very important.  相似文献   

8.
A significant increase in summer temperatures has been observed for the period 1996–2011 in Poznań, Poland. The phenological response of four weed taxa, widely represented by anemophilous species (Artemisia spp., Rumex spp. and Poaceae and Urticaceae species) to this recent climate warming has been analysed in Poznań by examining the variations in the course of airborne pollen seasons. Pollen data were collected by 7-day Hirst-type volumetric trap. Trends in pollen seasons were determined using Mann–Kendall test and Sen’s slope estimator, whereas the relationships between meteorological and aerobiological data were established by Spearman’s rank correlation coefficient. Significant trends in pollen data were detected. The duration of pollen seasons of all analysed taxa increased (from +2.0 days/year for Urticaceae to +3.8 days/year for Rumex), which can be attributed to a delay in pollen season end dates rather than earlier start dates. In addition, the intensity of Artemisia pollen seasons significantly decreased and correlates with mean July–September daily minimum temperatures (r?=??0.644, p?Rumex pollen seasons. The results of this study show that observed shifts in weed pollen seasons in Poznań, i.e. longer duration and later end dates, might be caused by the recorded increase in summer temperature. This influence was the strongest in relation to Artemisia, which is the taxon that flowers latest in the year. The general lack of significant correlations between Rumex and Urticaceae pollen seasons and spring and/or summer temperature suggests that other factors, e.g. land use practices, could also be partially responsible for the observed shifts in pollen seasons.  相似文献   

9.
Teresa Ozimek 《Hydrobiologia》2006,570(1):127-131
Changes in submerged macrophyte communities in the eutrophic Lake Mikołajskie have been studied for the last 40 years. As the recent commissioning of a number of sewage treatment plants within the complex of the Mazurian Great Lakes has led to an improvement in water transparency, it was expected that species composition would start to return to the state present before intensive eutrophication. The role of seed and oospore banks in the reconstruction of submerged macrophytes is analysed on the basis of laboratory experiment. Cores of sediments (9 cm long) were collected from the littoral of Lake Mikołajskie. The cores were divided in 3 cm layers and were incubated under laboratory conditions. Five species of submerged macrophytes were germinated from the propagule banks. The richest in viable propagules was the deepest layer and poorest in active propagules was the shallowest layer of sediment. The recolonization of the littoral zone of Lake Mikołajskie by species, which occurred at a earlier period in the lake’s history is possible because viable propagules have persisted in deeper sediments.  相似文献   

10.
A 72 cm peat core from a spring mire reveals 3300 years of vegetation history in the Hoher Fläming, a landscape formed by the penultimate glaciation in southeastern Brandenburg. Primeval beech-oak forest dominated from a.d. 550 to 1200, prior to local forest clearance. Existing maps showing the natural and potential natural vegetation as pine and oak need to be revised. Local woodland cutting in the 12th century and grassland use since the 15th century affected the development of the helokrene (spring-fed) mire deposits from alder carr to mesotrophic fen vegetation and then to the present-day Sphagnum fallax-Juncus acutiflorus wet meadows. Vegetation and mire history link together the Hoher Fläming and adjacent landscapes on a northwest-southeast gradient of suboceanic to subcontinental climate. Moreover it represents a geographical and altitudinal transition of lowland and hill vegetation from 30 to 200 m a.s.l. to the montane belts of the palynologically well investigated Harz mountains. However, regarding some trees and herbs, the Hoher Fläming does not belong to the Hercynian region and type of vegetation.  相似文献   

11.
The problem of developing a 2-week-on ahead forecast of atmospheric cypress pollen levels is tackled in this paper by developing a principal component multiple regression model involving several climatic variables. The efficacy of the proposed model is validated by means of an application to real data of Cupressaceae pollen concentration in the city of Granada (southeast of Spain). The model was applied to data from 11 consecutive years (1995–2005), with 2006 being used to validate the forecasts. Based on the work of different authors, factors as temperature, humidity, hours of sun and wind speed were incorporated in the model. This methodology explains approximately 75–80% of the variability in the airborne Cupressaceae pollen concentration.  相似文献   

12.
The investigated problem was whether and to what an extent the elements of weather conditions were associated with changes in the concentration of Ambrosia pollen in air. The study was carried out in the years 1997–2004 using the volumetric method. Ragweed did not occur in the flora of the town of Rzeszów and its vicinity, but every year its pollen occurred at concentrations considerably exceeding the threshold values for the allergic response. The pollen seasons usually began from near the end of August to the first part of September. The values of daily concentrations varied greatly: days without pollen grains being frequently noted while single grains occurred long before and after the season. The effect of the elements of weather on changes in the concentration of pollen in the air was slight. Taking into account all meteorological parameters, it can be stated that an increase in the number of pollen grains is connected with increased temperature and higher wind speeds, but negatively correlated with humidity and rainfall. These relationships can usually be explained by the effects of the type of weather taking place over the wider region. The analysis of the results showed that pollen was probably transported from distant regions. The mean angle at which the greatest pollen concentrations were recorded corresponded to the SE wind direction. The analysis of synoptic phenomena during the pollen season confirms the thesis about the long-distance transport from the south, southeast and southwest. A close dependence was also found between the starting date of the season and the sum of maximum temperatures and the sum of differences between the maximum and minimum temperatures.  相似文献   

13.
The first results are presented of an aerobiological analysis of the atmosphere of the town of Almería, carried out between November 1995 and October 1996. A Lanzoni volumetric spore trap was used for sample collection. The composition and seasonal evolution of the pollen spectrum were determined over a 1-year period in relation to the vegetation and climatic conditions of the study area. Twenty-six pollen types were identified as accounting for >0.05% of the total pollen collected. The main sources of airborne pollen were Palmae (17.76%),Olea (16.10%), Chenopodiaceae/Amaranthaceae (13.99%), Urticaceae (10.18%) and Poaceae (8.64%). The annual pollen variation presented a period of maximum emission from March to June, with a subsequent, less intensive period from August to November. The minimum pollen values were obtained from December to February. The highest concentrations occurred in May, which was also the month which presented the highest pollen diversity, whereas the lowest values were observed in January.  相似文献   

14.
One hundred fecal samples were collected during research on Eurasian lynx ecology and food habits in the Polish part of the Bia?owieza Primeval Forest (BPF) from 2001 to 2006. Seventy-three percent of samples contained eggs or larvae of helminths. A total of 10 species of helminths was identified, including 3 Cestoda (Diphyllobothrium latum, Spirometra janickii, and unidentified species of Taeniidae), 1 Trematoda (Alaria alata), and 6 Nematoda (Aelurostrongylus abstrusus, Ancylostoma tubaeforme, Eucoleus aerophilus, Metastrongylus sp., Nematodirus sp., and Toxocara cati). Alaria alata has not been reported previously in lynx. A statistical comparison of the 2 techniques used to isolate eggs, i.e., flotation and sedimentation, indicates that sedimentation was more effective.  相似文献   

15.
The diurnal variation of airborne pollen concentrations of Alnus, Betula, Pinus, Poaceae, Urtica and Artemisia was examined at the sampling station in Gdańsk, northern Poland. Diurnal patterns of Alnus and Pinus pollen show distinctly lower values and low frequency of diurnal maxima between midnight and late morning and a clear rise of pollen counts at around noon. The rather high values remain during the afternoon and evening. The Betula pollen counts are almost evenly distributed along day and night and diurnal maxima appear in similar frequency at any time of day. Pollen concentrations of Poaceae increase at about 9.00 hours and remain high till late evening. Diurnal patterns of Urtica and Artemisia show very clear variation with high peaks at around 9.00 hours (Artemisia) and 13.00 hours (Urtica). The comparison of the data from Gdańsk with the data from other aerobiological stations shows very similar general features in the diurnal patterns irrespective the region or the local situation.  相似文献   

16.
As published by the Intergovernmental Panel on Climate Change (IPCC) global warming is a reality and its impact is huge like the increase of extreme weather events, glacier recession, sea level rise and also effects on human health. Among them allergies to airborne pollen might increase or change in pattern due to the invasion of new allergic plants or due to different behavior of plants like earlier flowering. In this study we used the longest Swiss airborne pollen data set to examine the influence of the temperature increase on the time of flowering. In the case of Basel, where pollen data for 38 years are available, it was shown that due to a temperature increase the start of flowering in the case of birch occurred about 15 days earlier. Apart from a shift of the start of the flowering there is also a trend towards higher annual birch pollen quantities and an increase of the highest daily mean pollen concentrations. Due to global warming and because symptoms may appear earlier in the year people suffering from a pollen allergy might face a new unaccustomed situation.  相似文献   

17.
A continuous record of sedimentation in spring-fed fens makes them suitable for detailed palaeoenvironmental studies. A newly investigated cupola spring-fed fen (Paw?ów site), located in the Lublin chalkland, eastern Poland, was the object of our study. This special karst region is characterised by the occurrence of Upper Cretaceous carbonate rocks in the substratum. Sedimentological observations indicated strong variability of biogenic-carbonate series in the deposits (=peat-tufa rhythmite), reflects changes of accumulation conditions (oxidising versus reducing), resulting from alternate occurrence of warmer and cooler periods. Difficulties in pollen analysis due to oxidising conditions necessitate a multidisciplinary approach for palaeoenvironmental reconstruction. We used a multidisciplinary approach (sedimentological, palaeobotanical, geochemical analyses and radiocarbon dating) to determine the main evolutionary stages of this unique fen ecosystem and to discuss the role of local or/and regional factors in its development. Pollen and plant macrofossil analyses, supported by radiocarbon dating, proved that the bottom part of the cores represents the Late Glacial–Early Holocene stages of the fen development. A comparative analysis of palaeoenvironmental data showed close resemblance between the Paw?ów fen and the earlier studied fens in eastern Poland and Central-Eastern Europe, and the connection between their development and supraregional hydrological-climatic factors. The results indicated also the influence of the morphological position of such a type of ecosystem on the development of a continuous deposit succession. The occurrence of a river valley in close proximity of the Paw?ów site resulted in the lack of tufa deposits from the Atlantic period, because of an erosional phase in the river valley.  相似文献   

18.
Characteristics of the reproductive behaviour of wolves (Canis lupus) were studied by radio-tracking and snow-tracking of four packs in Białowieża Primeval Forest (BPF), Poland, in 1995–1999. Signs of mating occurred between 12 January and 22 March. Parturition occurred between 19 April and 12 May, and the denning period lasted for 49–64 days. During that time, wolves used 1–3 den sites, spending on average 27 days at each site. The dens were never reused in consecutive years, but year after year the breeding sites were located in the same parts of the pack’s territory. Ten days before parturition pregnant females reduced their normal mobility by half (from 23 to 13.5 km day−1, on average). During the ten days post-partum, they spent 85% of their time with pups and travelled 3.9 km day−1, only. On days 11–30 after parturition, females spent 74% of their time tending pups and increased their daily movement distance to a mean of 13.3 km. The females resumed full mobility 50–70 days after parturition, which coincides with termination of the weaning process. Anecdotal observations indicated that pups were tended by other pack members while the mother was absent. Compared with the years 1947–1950, in 1995–1999 the breeding season of wolves in BPF occurred two weeks earlier. A possible reason was the 1 to 1.5-degree increase in the mean annual temperature during the last 50 years.  相似文献   

19.
The titanosaur sauropod Bonatitan reigi is redescribed. The material collected, originally interpreted as pertaining to two different individuals, is reorganised in five individuals, and the original type specimen is separated into three different individuals. One of the braincases is designated as a new type specimen. Some materials are described by the first time (sacral ribs, distal caudal, chevrons, metacarpals, astragalus and metatarsals), others reinterpreted as different bones (‘ulna’ and ‘radius’). The diagnosis of B. reigi is emended, removing some of the original characters (longitudinal groove located on the suture between the parietals that continues posteriorly over the supraoccipital to the foramen magnum) and adding some new (small paired pits on the frontals and posterior ridge of the metacarpal IV). The phylogenetic analysis does not support B. reigi as a member of the Saltasaurinae, but rather as a basal member of a broad clade of sauropods that in turn is recovered as the sister group of the Saltasauridae.  相似文献   

20.
The research on the W?oc?awek Reservoir (WR), situated on the Lower Vistula River (Poland), was carried out during two periods: between 1986 and 2002, hydrochemistry was studied, and between 1994 and 2000 – plankton. WR is 70 km2 in area, its capacity is 370 × 106 m3 and the retention time with the average flow rate (Q) amounts to 930 m3 s?1 – only 5 days (!). Until 2002, due to cyclic work of a hydroelectric power plant, considerable variability in the daily flow rate was recorded (from 600 to 1800 m3 s?1). Its specific hydrology and fluvial character mean that WR functions in a completely different way compared to dam reservoirs described in textbooks, with significantly longer retention time.WR significantly improves most of the water quality variables in the river. It reduces the concentration of suspended matter (on average by more than 50%), Ptot (by 16%), BOD5 (by 40%) and chlorophyll “a” (by 50–60%) (unpublished data).Phytoplankton is rich in species – altogether 441 taxa, with the count of 7.4 × 106 individuals per dm?3 and biomass of 16 mg dm?3. Throughout the research period, a significant reduction in the abundance of phytoplankton was recorded in WR, sometimes more than 60%. The total number of zooplankton taxa at the site upstream from WR and in the reservoir was almost identical (68 and 67), however in the reservoir itself, a small decrease in the number of Rotifera species and an increase in the number of Crustacea species was observed, as well as a significant, fourfold increase in the total zooplankton biomass. The aforementioned reduction of phytoplankton and enrichment of the river with Crustacea are one of the major biocenotic consequences of the functioning of the W?oc?awek Reservoir.  相似文献   

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