Understanding hourly patterns of Olea pollen concentrations as tool for the environmental impact assessment.

Bioinformatics clustering application for mining of a large set of olive pollen aerobiological data to describe the daily distribution of Olea pollen concentration. The study was performed with hourly pollen concentrations measured during 8 years (2011-2018) in Extremadura (Spain). Olea pollen season by quartiles of the pollen integral in preseason (Qt: 0%-25%), in-season (Q2 and Q3: 25%-75%) and postseason (Q4: 75%-100%). Days with pollen concentrations above 100 grains/m(3) were clustered according to the daily distribution of the concentrations. The factors affecting the prevalence of the different clusters were analyzed: distance to olive groves and the moment during the pollen season and the meteorology. During the season, the highest hourly concentrations during the day where between 12:00 and 14:00, while during the preseason the highest hourly concentrations were detected in the afternoon and evening hours. In the postseason the pollen concentrations were more homogeneously distributed during 9-16 h. The representation shows a well-defined hourly pattern during the season, but a more heterogeneous distribution during the preseason and postseason. The cluster dendrogram shows that all the days could be clustered in 6 groups: most of the clusters shows the daily peaks between 11:00 and 15:00 with a smooth curve (Cluster 1 and 3) or with a strong peak (2 and 5). Days included in duster 9 shows an earlier peak in the morning (before 9:00). On the other hand, cluster 6 shows a peak in the afternoon, after 15:00. Hourly concentrations show a sharper pattern during the season, with the peak during the hours close to the emission. Out of the season, when pollen is expected to come from farther distances, the hourly peak is located later from the emission time of the trees. Significant factors for predicting the hourly pattern were wind speed and direction and the distance to the olive groves. (C) 2020 Elsevier B.V. All rights reserved

HYSPLIT as an environmental impact assessment tool to study the data discrepancies between Olea europaea airborne pollen records and its phenology in SW Spain.

The olive tree (Olea europaea) is a native evergreen tree in the Mediterranean region, being one of the most important causes of seasonal respiratory allergies in Mediterranean countries. This work aims to relate flowering phenology, source tree distribution, meteorology, and airborne pollen records for this species and to analyse the possible arrival of air masses from distant areas during days when differences between the phenological and pollen peaks. Aerobiological sampling was carried out in Badajoz (SW Spain) for 4 years (2016-2019) using a Hirst volumetric sampler. Trees were geolocalized in the city and surrounding areas. The pollination phenology of 15 specimens was studied for four years (2016-2019) during the months from April to June. The daily data for the whole period and the hourly data for the four years, including pollen records and meteorology, were analysed. The comparison between the pollen records and sources distribution was assessed. The main pollen season (thereafter, MPS) lasted an average of 34.5 (29-40) days. Phenological observations indicate that pollination occurred for 26.5 days and was mostly within the period of recorded airborne pollen; however, were days with airborne pollen recorded outside the pollination period. In 2017 the peak day was recorded when the flowering period has reached only the 10%, in other seasons this value reached the maximum peak of pollen concentration was found only a few days after the maximum of flowering. The hourly analysis showed that the maximum pollen concentrations were reached just after noon. The analysis of pollen sources and pollen records showed a close relationship with the predominant winds and tree distributions. The observed discrepancies between phenological and aerobiological data (in 2017 and 2018) were explained by the movement of air masses and long-distance transport

Phenology of Cupressaceae urban infrastructure related to its pollen content and meteorological variables.

Cupressaceae pollen is one of the major airborne allergens of the Mediterranean region and in other regions around the world. Pollen production of these species causes considerable allergic problems during winter, being this type of pollen the most abundant in this period of the year. This work aims to relate phenology, meteorology and airborne pollen records in these species. Aerobiological sampling was carried out in Badajoz (SW Spain) from 2016 to 2018 using Hirst-type volumetric sampler. Pollination phenology was studied in 50 specimens, ten ofCupressus macrocarpa, ten ofCupressus arizonica, 15 ofCupressus sempervirensand 15 ofPlatycladus orientaliswith a frequency of 3-4 days on average during the months of January to March. In all cases, five specimens were in the surrounding of pollen station and at least five of them 4 km apart. For phenology, BBCH methodology was used. Daily data for the whole period and hourly data for the last 2 years were analyzed, including pollen records and meteorology. Comparison between pollen records and sources distribution was assessed. Main pollen season lasted on average 91 (89-94) days. In all the years, the peaks of phenology of the different species can be matched with peaks of airborne pollen records, considering that rain can prevent a more precise correspondence

Producing urban aerobiological risk map for cupressaceae family in the SW iberian peninsula from LiDAR technology.

Given the rise in the global population and the consequently high levels of pollution, urban green areas, such as those that include plants in the Cupressaceae family, are suitable to reduce the pollution levels, improving the air quality. However, some species with ornamental value are also very allergenic species whose planting should be regulated and their pollen production reduced by suitable pruning. The Aerobiological Index to create Risk maps for Ornamental Trees (AIROT), in its previous version, already included parameters that other indexes did not consider, such as the width of the streets, the height of buildings and the geographical characteristics of cities. It can be considered by working with LiDAR (Light Detection and Ranging) data from five urban areas, which were used to create the DEM and DSM (digital elevation and surface models) needed to create one of the parameters. Pollen production is proposed as a parameter (alpha) based on characteristics and uses in the forms of hedges or trees that will be incorporated into the index. It will allow the comparison of different species for the evaluation of the pruning effect when aerobiological risks are established. The maps for some species of Cupressaceae (Cupressus arizonica, Cupressus macrocarpa, Cupressus sempervirens, Cupressocyparis leylandii and Platycladus orientalis) generated in a GIS (geographic information system) from the study of several functions of Kriging, have been used in cities to identify aerobiological risks in areas of tourist and gastronomic interest. Thus, allergy patients can make decisions about the places to visit depending on the levels of risk near those areas. The AIROT index provides valuable information for allergy patients, tourists, urban planning councillors and restaurant owners in order to structure the vegetation, as well as planning tourism according to the surrounding environmental risks and reducing the aerobiological risk of certain areas