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The use of meteorological autocorrelation variables and pollen concentrations from previous days, coupled with classification of meteorological data according to multivariate analysis techniques, is shown to improve the predictive power of multiple regression models for daily pollen forecasts. This paper presents an investigation of the meteorological and autocorrelation variables which influence pollen counts in Cartagena, from 1995 to 1999, as a basis for the development of predictive models. The analysis of total pollen concentrations, and especially Chenopodiaceae-Amaranthaceae, was determined. Initially, forecasting models for total pollen counts were developed, using data from 1995 to 1998, and autocorrelation and meteorological variables. Secondly, predictive models were developed for different meteorological situations, which improved the results by decreasing the number of predictive parameters. Finally, data from 1999 were used to validate the predictive models. [ABSTRACT FROM AUTHOR]

This paper presents data of airborne pollen concentration of Pinus, Platanus, Quercus, Betula, Poaceae and Castanea, the most abundant pollen types, during the last eight years, in Santiago de Compostela (NW Iberian Peninsula). We determined their respective principal pollen release periods and analysed statistically the influence of the main meteorological parameters on their pollen concentration, obtaining a negative correlation with precipitation and a positive correlation with temperature, in the majority of the cases, during these years. A detailed study of accumulated pollen values, in relation to accumulated average temperatures and the precipitation distribution, enabled us to establish a relationship between these parameters and the principal pollination period of each of these taxa. [ABSTRACT FROM AUTHOR]

An analysis was made of the protein content of pollen loads produced by the bees in a hive situated in Viana do Bolo (Ourense, north-west Spain), to establish whether or not the relative quantity of protein in the pollen of each plant species influences the preference made by the bee of the flowers that supply pollen to the hive. This analysis was performed on all types of pollen that formed more than 5% of the pollen spectrum. Pollen load samples were collected directly from the hive from March to September. Pollen loads were separated by colour, and their specific homogeneity was confirmed microscopically. The Bradford method has been used for protein extraction and spectrophotometry was used for the determination of protein content. The results show that the different pollen loads have high protein content. Pollen of the plant species that reached relatively higher percentages in the pollen spectrum are also those that have the highest protein content. These were Cytisus scoparius type, uncultivated Poaceae, Quercus robur type, Sanguisorba minor, Salix fragilis and Spergularia rubra type. The pollen of the systematic units, which had pollen loads that could be identified at the level of species, maintained a constant value of protein content independently of the date the samples were obtained. The pollen of the systematic units, which had pollen loads that could be identified at the level of pollen type, has varied in protein content in the analyses performed on samples obtained on different dates. This result is due to the fact that the different species that integrate the pollen type flower on different dates, and thus have a pollenkitt with different characteristics. [ABSTRACT FROM AUTHOR]

The pollen of nine endemic taxa of the Gonospermum Less., Lugoa DC. and Tanacetum L. complex and of T. parthenium L. (introduced species from the Canary Islands) was studied using light and scanning electron microscopy with the aim of extending the knowledge of their morphology and to investigate whether pollen morphology may help clarifying the controversial taxonomy of these taxa. Twenty six populations in the Canary Islands (Spain) were studied and the following parameters were measured: polar axis (P), equatorial diameter (E), polar exine thickness (Ex1), length (L) and thickness (A) of the spines in the meridional optical section, exine thickness at the centre of the mesocolpium in the interapertural area (Ex2) and distance between spines (De) in the equatorial optical section. The studies show that the pollen of the three genera is very similar regarding shape, apertures, and ornamentation, but may be distinguished by size and exine thickness. [ABSTRACT FROM AUTHOR]

A morphological study of three different types of dispersed Circumpolles pollen grains from the Toarcian-Aalenian of the Fuentelsaz section (Spain) was performed using conventional wide field and confocal laser scanning microscopy (CSLM). The CSLM data allowed scanning electron microscope-like three-dimensional reconstructions to be made and showed that the most part of the studied pollen have taxonomic features characteristic of the Mesozoic genus Classopollis. At the species level, Classopollis torosus and Classopollis classoides were identified. The third form studied is characterized by the presence of Ubisch bodies adhering to the pollen wall. [ABSTRACT FROM AUTHOR]

The timing of pollen appearance in the atmosphere provides a general idea of the flowering onset of plants over a wide area. Woody plants in temperate regions have evolved mechanisms to preserve cells from the risk of frost during adverse weather conditions in the period prior to flowering regulated mainly by temperature. A number of indices have been developed to quantify the rest and heat requirements of temperature, which will enable the plant to adapt to environmental conditions. However, flowering is a dynamic and complex phenomenon and it is difficult to separate individual effects of different meteorological parameters. The use of modified bioclimatic indices could be a major step forward. In this study the Alnus glutinosa flowering in four different areas in north-western Spain in the period 1995-2003 is examined, and trends identified by means of information gathered by Hirst pollen traps. Temperature plays an important role in the maturation of reproductive organs and pollen production. Comparison with bioclimatic indices showed that temperature during the 25-55 days preceding pollen release was the main controlling factor, and that relationship between flowering time and bioclimatic indicator values differs according to local conditions. In colder areas, rest and heat temperature requirements are greater because the trees need protection over a longer period; in the Mediterranean region of north-western Spain, the rest temperature requirement and the threshold temperature are both higher than in Eurosiberian areas. Ombrothermic, Continentality and Thermicity indices are thus useful tools for characterizing the various bioclimatic areas of north-western Spain. [ABSTRACT FROM AUTHOR]

Since the beginning of aeropalynology, aerobiologists have tried to develop models able to predict the pollen load of the atmosphere to help physicians and patients suffering pollen allergies to improve the efficiency of pollen allergies prophylaxis. Some models have been developed by aerobiological services and are used for real time predictions, now provided online. They are statistical models and require the pollen load of the previous days as input, as well as statistics on the pollen load of the previous years, daily meteorological data and geographic information on the pollen sources. Here we propose to use process-based phenological models to predict the time course of the pollen load of the atmosphere using solely daily mean temperatures as input. The model proposed has been fitted and validated for 13 major allergenic taxa ( Alnus , Artemisia , Betula , Castanea , Corylus , Cupressaceae, Olea , Plantago , Platanus , Populus , Poaceae, Quercus and Tilia ) in different areas of France and Spain. The model has been integrated into a freeware called PPF (Positive Pollen Forecast), which will be made available from the 5 th Framework EU project POSITIVE web page at: http://www.forst.tu-muenchen.de/LST/METEOR/positive/. [ABSTRACT FROM AUTHOR]

Temperature is one of the main factors affecting the start of flowering in tree species that flower at the beginning of spring. Knowledge of the chilling and heat needs required by plants to overcome the period of dormancy enables us to determine the onset of pollination, which is of great importance to allergy sufferers. This study attempted to obtain behaviour models with a view to determining both the onset of the olive pollen season and daily pollen concentrations during the pollination period in Vigo. Monitoring was carried out using a Lanzoni VPPS 2000 pollen trap, from 1995 to 2002 inclusive. Olea pollen is mainly detected during the spring, principally in May. Given the geographical location, the very limited presence of this tree in the study area and the low Olea pollen concentrations detected in northern Spain as a whole, the values recorded here in the atmosphere of Vigo are particularly striking. A strong correlation was observed between total quantity olive pollen collected over the season and rainfall recorded during the second fortnight in February. According to the proposed model, an average of 680 Chilling Hours (CH) are necessary to overcome the chill period and break the state of bud dormancy, and 481 Growth Degree Days (GDD) °C are needed to induce flowering. Models for predicting daily mean pollen concentrations combine temperature and the previous days' pollen concentrations as predictor variables to provide a high level of prediction. [ABSTRACT FROM AUTHOR]

The pollen content of twenty-four unifloral honey samples from twelve different apiaries in La Palma (Canary Islands) was subjected to qualitative and quantitative melissopalynological analysis. The quantitative analysis showed that 4% of the honey belonged to Maurizio's Class I, 8% to Class II, 58% to Class III, 17% to Class IV and 13% to Class V. According to the qualitative analysis, eight honeys were typified as unifloral of Castanea sativa, five of Carlina salicifolia, three of Echium brevirame, three of Reseda luteola, two of Erica arborea, two of Lotus hillebrandii and one of Lamiaceae Origanum vulgare ssp. virens-type. No honeydew elements were found. 62 pollen types were identified belonging to 42 different families. There is no pollen type common to all samples but Foeniculum vulgare-type is present in 22 of the samples (91.7%) and the combination Cistus sp., Erica arborea, Aspalthium bituminosum, Origanum vulgare ssp. virens-type and Rumex sp. in 21 (87.5%). The organoleptic analysis indicated that they are of good quality. [ABSTRACT FROM AUTHOR]

The recent increase in the number of aerobiological stations means that it is possible to make comparative studies, not only to ascertain similarities and differences between pollen counts in different places, but also to ascertain the most suitable places for them to be situated and the most adequate distance which should be established between them. To this end, we present a statistical comparison of the results obtained for the pollen of the ten most abundant taxa, as recorded in the sampling stations of Malaga and Estepona (South of Spain) during 1995-97. The stations are 90km apart. The variables compared were the following: mean daily concentrations (for each year and the total period studied), the mean concentration of the three years for the same date (trend) and the deviation from this mean (for each year and taken as a whole). The interannual differences within and between stations were taken into account as regards the association, concentration and distribution of the variables. The results of the tests applied point that significant differences between the two stations were observed for most of the pollen types studied. Despite of this, a positive and significant correlation exists between the mean daily concentrations of the different taxa at the two stations, which is an important finding if we consider the possibility of making reliable predictions for one sampling site based on the data obtained at the other. [ABSTRACT FROM AUTHOR]

Aerobiological studies carried out in the atmosphere of Granada using a Hirst-type volumetric spore trap during the period 1993-1996 show that there is not a single diurnal pattern for olive pollen (Olea europaea L.) over the course of the main pollen season. Examination of the behaviour of airborne olive pollen concentration allows the establishment of either regular (54.4% of the studied days) or irregular (45.6% of the time) patterns of diurnal variation. On a given day, the pattern found will depend on a combination of different factors: the origin of the captured pollen (either local or regional), source distribution in relation to the pollen sampler, topography, and different meteorological variables (mean air temperature, sunshine hours, total rainfall, relative humidity, wind speed and direction, and periods of calm). Regional sources were significant contributors to city centre pollen concentrations when moderate (< 10 km/h) winds from the 4th quadrant and warm temperatures (19-26 C) allow swift transport from the W-NW of the province. [ABSTRACT FROM AUTHOR]