Spring Influences on Olive Flowering and Threshold Temperatures Related to Reproductive Structure Formation

Several bioclimatic studies have been developed over recent years considering temperature trends and their influence on vegetative and reproductive phenomena during plant growth. In the applied aerobiology laboratory of Perugia University, various studies of olive (Olea europaea L.) flowering and its relationship with climatic variables have been conducted. Since 1999, a flowering monitoring network in central–southern Italy has been working to track the biological phenomena over the years, the possible differences between the monitoring stations, and the relationships with climate. Olive flowering was monitored in 15 monitoring stations located in four Italian regions (Campania, Calabria, Puglia, and Sicily) representing ≈90% of national olive territories. The flowering phenophase was studied through pollen emission monitoring, making use of scientific instruments that capture defined volumes of atmosphere and allow us to ascertain the pollen emission trends, thereby determining daily average pollen concentrations (pollen grains/m3). The combined analysis of pollen monitoring and meteorological data permitted identifying various groups of stations characterized by the fact that better relationships between reproductive structure development and growing degree-days are obtained with different spring threshold temperatures (low 7 to 10 °C or high 11 to 14 °C). Moreover, the study permitted demonstrating particular meteorological and biological behaviors, providing useful information about plant–climate relationships in a species of economic interest affected by interincompatibility.

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Neural networks for increased accuracy of allergenic pollen monitoring

Scientific Reports ◽

10.1038/s41598-021-90433-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Marcel Polling ◽

Chen Li ◽

Lu Cao ◽

Fons Verbeek ◽

Letty A. de Weger ◽

...

Keyword(s):

Neural Networks ◽

Airborne Pollen ◽

Pollen Grains ◽

Allergenic Pollen ◽

Herbarium Specimens ◽

Pollen Monitoring ◽

Pollen Concentrations ◽

Source Of Information ◽

Urticaceae Pollen

AbstractMonitoring of airborne pollen concentrations provides an important source of information for the globally increasing number of hay fever patients. Airborne pollen is traditionally counted under the microscope, but with the latest developments in image recognition methods, automating this process has become feasible. A challenge that persists, however, is that many pollen grains cannot be distinguished beyond the genus or family level using a microscope. Here, we assess the use of Convolutional Neural Networks (CNNs) to increase taxonomic accuracy for airborne pollen. As a case study we use the nettle family (Urticaceae), which contains two main genera (Urtica and Parietaria) common in European landscapes which pollen cannot be separated by trained specialists. While pollen from Urtica species has very low allergenic relevance, pollen from several species of Parietaria is severely allergenic. We collect pollen from both fresh as well as from herbarium specimens and use these without the often used acetolysis step to train the CNN model. The models show that unacetolyzed Urticaceae pollen grains can be distinguished with > 98% accuracy. We then apply our model on before unseen Urticaceae pollen collected from aerobiological samples and show that the genera can be confidently distinguished, despite the more challenging input images that are often overlain by debris. Our method can also be applied to other pollen families in the future and will thus help to make allergenic pollen monitoring more specific.

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Tree Pollen Spectra and Pollen Allergy Risk in the Osijek-Baranja County

Archives of Industrial Hygiene and Toxicology ◽

10.2478/10004-1254-64-2013-2235 ◽

2013 ◽

Vol 64 (1) ◽

pp. 115-122 ◽

Cited By ~ 4

Author(s):

Magdalena Sikora ◽

Marina Valek ◽

Zdenka Šušić ◽

Vera Santo ◽

Dario Brdarić

Keyword(s):

Airborne Pollen ◽

Pollen Allergy ◽

Pollen Grains ◽

Weather Conditions ◽

Research Information ◽

Tree Pollen ◽

Pollen Concentrations ◽

North Eastern ◽

Measuring Site ◽

Monitoring Stations

The forests of north-eastern Croatia, as well as various plants and trees in the parks and streets of the Osijek-Baranja County, produce large amounts of pollen during the pollen season, which can cause allergy symptoms in pollen sensitive individuals. The aim of this study was to determine the most frequent types of pollen in this area and estimate possible health risks, especially the risk of allergy. In 2009 and 2010, the staff of the Health Ecology Department of the Osijek Public Health Institute monitored tree pollen concentrations in four cities from the Osijek - Baranja County (Osijek, Našice, Đakovo and Beli Manastir) using a Burkard volumetric instrument. The results were affected by weather conditions. Windy and sunny days facilitated the transfer of pollen, whereas during rainy days, the concentration of pollen grains decreased. High pollen concentrations of Cupressaceae/Taxaceae, Betulaceae, Salicaceae and Aceraceae could be the cause for symptoms of pollen allergy. In 2009, conifers, birch and poplar pollen were dominant at all monitoring stations with 5000 pollen grains (PG), 3188 PG and 3113 PG respectively. The highest number of pollen grains was recorded at measuring site Osijek. The variations in airborne pollen concentration between pollen seasons were recorded at all monitoring stations. The most obvious variations were recorded at measuring site Osijek. The usual pollination period lasts two to three months, which means that most pollen grains remain present from February to early June. However, the Cupressaceae / Taxaceae pollination periods last the longest and their pollen grains remain present until the end of summer. The risk of allergy was determined at four monitored measuring stations and the obtained data confirmed that the largest number of days with a high health risk was at the Đakovo measuring station for a species of birch. The research information aims to help allergologists and individuals allergic to plant pollen develop preventive measures and proper treatment therapies.

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Automatic Image Classification Using Neural Networks Increases Accuracy for Allergenic Pollen Monitoring

10.21203/rs.3.rs-116766/v1 ◽

2020 ◽

Author(s):

Marcel Polling ◽

Chen Li ◽

Lu Cao ◽

Fons Verbeek ◽

Letty de Weger ◽

...

Keyword(s):

Airborne Pollen ◽

Pollen Grains ◽

Allergenic Pollen ◽

Herbarium Specimens ◽

Pollen Monitoring ◽

Pollen Concentrations ◽

Family Level ◽

Source Of Information ◽

Urticaceae Pollen

Abstract Monitoring of airborne pollen concentrations provides an important source of information for the globally increasing number of hay fever patients. Airborne pollen are traditionally counted under the microscope, but with the latest developments in image recognition methods, automating this process has become feasible. A challenge that persists, however, is that many pollen grains cannot be distinguished beyond the genus or family level using a microscope. Here, we assess the use of a Convolutional Neural Network (CNN) to increase taxonomic accuracy for airborne pollen. As a case study we use the nettle family (Urticaceae), which contains two main genera (Urtica and Parietaria) common in European landscapes which pollen cannot be separated by trained specialists. While pollen from Urtica species have very low allergenic relevance, those from several species of Parietaria are severely allergenic. We collect pollen from both fresh as well as from herbarium specimens and use these to train the CNN model VGG16. The model shows that Urticaceae pollen can be distinguished with 98.3% accuracy. We then apply our model on Urticaceae pollen collected from aerobiological samples and show that the genera can be confidently distinguished, despite the more challenging input images that are often overlain by debris. Our method can also be applied to other pollen families in the future and will thus help to make allergenic pollen monitoring more specific.

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Annual pollen sums of alnus in Lublin and Roztocze in the years 2001-2007 against selected meteorological parameters

Acta Agrobotanica ◽

10.5586/aa.2008.033 ◽

2012 ◽

Vol 61 (2) ◽

pp. 57-64 ◽

Cited By ~ 5

Author(s):

Bogusław M. Kaszewski ◽

Irena A. Pidek ◽

Krystyna Piotrowska ◽

Elżbieta Weryszko-Chmielewska

Keyword(s):

Pollen Grains ◽

Significant Negative Correlation ◽

Mean Value ◽

Pollen Deposition ◽

Data Series ◽

Total Precipitation ◽

Pollen Data ◽

Pollen Emission ◽

Pollen Concentrations ◽

June July

Alder (Alnus Mill.), as an anemophilous species, produces large quantities of easily dispersed pollen. Annual pollen sums recorded in south-eastern Poland (by the volumetric method - Lanzoni trap) and in the area of the village of Guciów in the Central Roztocze region (pollen deposition in Tauber traps) were compared. The height at which the respective trap sites were located as well as local and regional vegetation and the distance from the nearest alder communities differ in both cases, likewise, the climate of these two regions differ. The analysed pollen data series cover the years 1998-2007 in Roztocze and 2001-2007 in Lublin. Large differences have been noted in Alnus pollen deposition values between particular years. Among them, there were observed years of very high annual sums (2001, 2003, 2006), as well as years of very low pollen deposition values in both regions (2002, 2005, 2007). In the period in question, the mean value of annual Alnus pollen count for Lublin was 5372 alder pollen grains in m3 of air, and in Roztocze 1647 grains per cm2 of area. During the seven-year period of monitoring (2001-2007), very similar trends were noted with respect to airborne alder pollen concentrations at both trap sites. Pollen data have been analysed against meteorological factors affecting alder pollen production and deposition. These are total precipitation and mean monthly air temperature in June, July and August in the year preceding pollen emission and the same weather elements in January and February in the year of pollen emission. In Roztocze a statistically significant negative correlation has been found between Alnus pollen annual sums and total precipitation in August in the year preceding alder pollen emission and in February in the year of pollen emission. In both regions, the Spearman's correlation coefficient does not show any statistically significant values when comparing annual Alnus pollen sums with mean monthly temperatures of both January and February and summer months in the year preceding alder pollen emission.

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Complex system for earthquakes forecast using gas emission observations

10.5194/egusphere-egu2020-13025 ◽

2020 ◽

Author(s):

Victorin - Emilian Toader ◽

Iren-Adelina Moldovan ◽

Constantin Ionescu ◽

Alexandru Marmureanu ◽

Andrei Mihai

Keyword(s):

Acoustic Waves ◽

Meteorological Data ◽

Time Windows ◽

Monitoring Network ◽

Tectonic Stress ◽

Gas Emission ◽

Earthquake Forecast ◽

Gas Emissions ◽

Air Ionization ◽

Monitoring Stations

Romanian National Institute of Earth Physics (NIEP) develops a gas emission monitoring network as part of a multidisciplinary activity. The goal is to help organizations specialized in emergency situations with short-term earthquakes forecast and information related to pollution and effects of climate change. In Romania, the important seismic area is Vrancea where there are seismic and multidisciplinary monitoring stations. The methods and monitoring solutions are general and they could be applied in any place. The main part of our system is related to CO2, CO, radon, air ionization in correlation with earth radiation, air ionization, telluric currents, ULF radio waves disturbance, magnetic field, temperature in borehole, infrasound, acoustic waves and meteorological data. The monitoring stations are located on the faults in the curvature of the Carpathian Mountains. The first step is to determine the daily, seasonal and annual evolutions of gas emissions and ionization of the air for at least one year. We are looking for time intervals during which the seismic activity was reduced to determine the normal evolutions of the measured parameters. Then we can determine the effects of active seismic periods on gas emissions. We will apply several methods of analysis and will correlate the particularities of the geological structure in which the monitoring stations are located and the position of the epicenters of earthquakes. The present results are favorable to the analysis by integrating the values measured on variable time windows according to the case. Instantaneous values also include local effects that are not related to tectonic stress. Current measurements indicate the presence of CO at certain times of the day and at certain stations. This is not possible due to tectonic stress, but may be the result of pollution in short-distance cities and air currents that spread it.Key words: gas emission, multidisciplinary analysis, radon concentration, air ionization, multi-parametric monitoring, earthquake forecast, earthquake precursors

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Patterns in recent and Holocene pollen accumulation rates across Europe – the Pollen Monitoring Programme Database as a tool for vegetation reconstruction

Biogeosciences ◽

10.5194/bg-18-4511-2021 ◽

2021 ◽

Vol 18 (15) ◽

pp. 4511-4534

Author(s):

Vojtěch Abraham ◽

Sheila Hicks ◽

Helena Svobodová-Svitavská ◽

Elissaveta Bozilova ◽

Sampson Panajiotidis ◽

...

Keyword(s):

Forest Cover ◽

Monitoring Network ◽

Pollen Grains ◽

Individual Species ◽

Pollen Deposition ◽

Accumulation Rates ◽

Long Distance ◽

Pollen Monitoring ◽

Pollen Accumulation Rates ◽

Long Distance Transport

Abstract. The collection of modern, spatially extensive pollen data is important for the interpretation of fossil pollen assemblages and the reconstruction of past vegetation communities in space and time. Modern datasets are readily available for percentage data but lacking for pollen accumulation rates (PARs). Filling this gap has been the motivation of the pollen monitoring network, whose contributors monitored pollen deposition in modified Tauber traps for several years or decades across Europe. Here we present this monitoring dataset consisting of 351 trap locations with a total of 2742 annual samples covering the period from 1981 to 2017. This dataset shows that total PAR is influenced by forest cover and climate parameters, which determine pollen productivity and correlate with latitude. Treeless vegetation produced PAR values of at least 140 grains cm−2 yr−1. Tree PAR increased by at least 400 grains cm−2 yr−1 with each 10 % increase in forest cover. Pollen traps situated beyond 200 km of the distribution of a given tree species still collect occasional pollen grains of that species. The threshold of this long-distance transport differs for individual species and is generally below 60 grains cm−2 yr−1. Comparisons between modern and fossil PAR from the same regions show similar values. For temperate taxa, modern analogues for fossil PARs are generally found downslope or southward of the fossil sites. While we do not find modern situations comparable to fossil PAR values of some taxa (e.g. Corylus), CO2 fertilization and land use may cause high modern PARs that are not documented in the fossil record. The modern data are now publicly available in the Neotoma Paleoecology Database and aid interpretations of fossil PAR data.

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Variations in birch (Betula spp.) pollen seasons in Lublin and correlations with meteorological factors in the period 2001-2010. A preliminary study

Acta Agrobotanica ◽

10.5586/aa.2011.016 ◽

2012 ◽

Vol 64 (2) ◽

pp. 39-50 ◽

Cited By ~ 3

Author(s):

Krystyna Piotrowska ◽

Bogusław M. Kaszewski

Keyword(s):

Pollen Season ◽

Meteorological Factors ◽

Meteorological Data ◽

Birch Pollen ◽

Pollen Grains ◽

Significant Negative Correlation ◽

City Centre ◽

Seasonal Temperature ◽

Pollen Monitoring ◽

Pollen Seasons

In Poland birch belongs to the most important taxa producing allergenic pollen, therefore information on the start dates, duration and severity of the pollen season is very important for allergists and their patients as well as for climatologists. Birch pollen monitoring was conducted in Lublin using the volumetric method during the period 2001-2010. A Lanzoni VPPS 2000 trap was placed at a height of 18 m in the city centre. The pollen season was determined using three methods: 98%, 95%, and 90%. The present study also investigated correlations between the birch pollen season parameters and meteorological factors. A comparison of the above-mentioned methods shows that, in the conditions prevailing in Lublin, the most appropriate method to determine the birch pollen season is the 98% method, since in the case of the two other methods too large quantities of pollen grains are eliminated. Based on a comparative analysis of the meteorological data from the study period and the long-term averages, it can be concluded that in the recent years a clear increase in air temperature has been recorded in Lublin. The study found a statistically significant negative correlation of seasonal pollen concentration with rainfall and air humidity. When the pre-peak and post-peak periods were separated, these correlations were larger and related to different meteorological factors. The start of the pollen season was negatively correlated with temperature in February and March. The season duration depended on temperature (a positive correlation). The date of the seasonal maximum was positively correlated with seasonal temperature and negatively with temperature in April.

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Pollen Production of Quercus in the North-Western Iberian Peninsula and Airborne Pollen Concentration Trends during the Last 27 Years

Forests ◽

10.3390/f11060702 ◽

2020 ◽

Vol 11 (6) ◽

pp. 702

Author(s):

María Fernández-González ◽

Estefanía González-Fernández ◽

Helena Ribeiro ◽

Ilda Abreu ◽

F. Javier Rodríguez-Rajo

Keyword(s):

Climate Change ◽

Airborne Pollen ◽

Pollen Grains ◽

Maximum Temperature ◽

Pollen Production ◽

Pollen Monitoring ◽

Main Pollen Season ◽

Pollen Concentrations ◽

Oak Pollen ◽

The Impact

Natural forests are considered a reservoir of great biological diversity constituting one of the most important ecosystems in Europe. Quercus study is essential to assess ecological conservation of forests, and also of economic importance for different industries. In addition, oak pollen can cause high sensitization rates of respiratory allergies in pollen-allergy sufferers. This study sought to know the pollen production of six oak species in the transitional area between the Eurosiberian and Mediterranean Bioclimatic Regions, and to assess the impact of climate change on airborne oak pollen concentrations. The study was conducted in Ourense (NW Spain) over the 1993–2019 period. A Lanzoni VPPS 2000 volumetric trap monitored airborne pollen. A pollen production study was carried out in ten trees randomly selected in several Quercus forest around the Ourense city. Oak pollen represented around 14% of annual total pollen registered in the atmosphere of Ourense, showing an increasing trend during the last decade. Pollen production of the six studied oak species follow the proportions 1:1:2:5:90:276 for Q. ilex, Q. faginea, Q. rubra, Q. suber, Q. pyrenaica, and Q. robur respectively. We detected a significant trend to the increase of the annual maximum temperature, whereas a decrease of the maximum and mean temperatures during three previous months to oak flowering. This could be related with the detected trend to a delay of the oak Main Pollen Season onset of 0.47 days per year. We also found significant trends to an increase of the annual pollen integral of 7.9% pollen grains per year, and the pollen peak concentration of 7.5% pollen grains per year. Quercus airborne pollen monitoring as well as the knowledge of the reproductive behavior of the main oak species, bring us an important support tool offering a promising bio-indicator to detect ecological variations induced by climate change.

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Patterns in recent and Holocene pollen influxes across Europe; the Pollen Monitoring Programme Database as a tool for vegetation reconstruction

10.5194/bg-2020-217 ◽

2020 ◽

Author(s):

Vojtěch Abraham ◽

Sheila Hicks ◽

Helena Svobodová-Svitavská ◽

Elissaveta Bozilova ◽

Sampson Panajiotidis ◽

...

Keyword(s):

Forest Cover ◽

Monitoring Network ◽

Pollen Grains ◽

Tree Cover ◽

Pollen Deposition ◽

Long Distance ◽

Pollen Monitoring ◽

Pollen Accumulation Rates ◽

Long Distance Transport ◽

Regional Forest

Abstract. The collection of modern spatially extensive pollen data are important for the interpretation of fossil pollen diagrams. Such datasets are readily available for percentage data but lacking for pollen accumulation rates (PAR). Filling this gap has been the motivation of the pollen monitoring network, whose contributors monitored pollen deposition in modified Tauber-traps for several years or decades across European latitudes. Here we present this monitoring dataset consisting of 351 trap locations with a total of 2742 annual samples covering the period from 1981 to 2017. This dataset shows that climate parameters correlating with latitude determine pollen productivity. A signal of regional forest cover can be detected in the data, while local tree cover seems more important. Pollen traps situated beyond 200 km of the distribution of the parent tree are still collecting occasional pollen grains of the tree in question. PAR’s of up to 30 grains cm−2yr−1 in fossil diagram should therefore be interpreted as long distance transport. Comparisons to fossil data from the same areas show comparable values. Comparisons often demonstrate that similar high values for temperate taxa in fossils sites are found further south or downhill. While modern situations comparable to high PAR values of some taxa (e.g. Corylus) may be hard to find, CO2 fertilization and land use may case high modern PAR’s that are not documented in the fossil record. The modern data is now publically available in the Neotoma Paleoecology Database and hopefully serves improving interpretations of fossil PAR data.

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The importance of the stationary and individual pollen monitoring for the diagnostic of pollen allergy

Acta Agrobotanica ◽

10.5586/aa.2006.039 ◽

2012 ◽

Vol 59 (1) ◽

pp. 373-383 ◽

Cited By ~ 1

Author(s):

Dorota Myszkowska ◽

Barbara Bilo ◽

Danuta Stępalska ◽

Jerzy Wołek

Keyword(s):

Rank Correlation ◽

Pollen Allergy ◽

Pollen Grains ◽

State Committee ◽

Pollen Monitoring ◽

Low Concentrations ◽

Pollen Concentrations ◽

Burkard Trap ◽

Pollen Seasons ◽

Local Plants

The aim of the study was to evaluate pollen seasons of selected taxa with particular reference to allergic taxa such as birch (Betula sp.), grasses (Poaceae), mugwort (Artemisia sp.) in Cracow in 2003 and 2004 (project number 3 PO5D 034 24 funded by the State Committee for Scientific Research). Pollen concentrations obtained using the stationary Burkard trap and personal Partrap FA 52 were compared. The volumetric method was used in the study. Average daily concentrations (pollen grains × m-3) were obtained by counting pollen grains every hour along 4 longitudinal transects and applying an appropriate conversion factor. Duration of the pollen season was determined using the 95% method. Variations in annual totals of pollen grains (birch and mugwort), in start dates (especially for grasses) and in the season duration (birch and grasses) were found. The comparison of pollen concentrations obtained using the stationary and personal traps at the same place showed non statistically significant correlation for all the studied taxa and statistically significant correlations for birch, mugwort and grasses (Spearman rank correlation). However, the statistically significant differences between the concentrations obtained using Burkard and Partrap carried by patients (Wilcoxon's test) were noted. Very low concentrations of pollen grains measured indoor (work, flats) and the influence of the local plants growing in separate place (courtyard of the Allergology Department) on the pollen concentration were found.

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