F. Alba

Detection of airborne allergen (Ole e 1) in relation to Olea europaea pollen in S Spain

Background In recent years, it has been demonstrated that the air carries not only airborne pollen but also plant particles of smaller size that have allergenic activity, and, being within the respirable range, these particles can trigger rapid attacks in the lower respiratory tract. The study of particles according to size (0.7–40 μm) could provide valuable information on the real allergenic activity in the atmosphere.

Aerobiological analysis of Olea europaea L. pollen in different localities of southern Spain Forecasting models

Pollen from olive trees (Olea europaea L.) is one of the main airborne allergens of the Mediterranean region. We have performed a comparative analysis of the behaviour of Olea pollen in the atmosphere at different localities in southern Spain with different biogeographic and climatic characteristics. Sampling over several years with Burkard or Lanzoni volumetric collectors was performed in the four cities of Córdoba, Jaén, Málaga and Granada. The pollen season spans primarily April to June, with the heaviest concentrations in May and peak days registering: 3890 grains/m (Córdoba), 6730 grains/m (Jaén), 2819 grains/m (Málaga), and 1884 grains/m (Granada). These quantities make these cities prime centres of seasonal allergic rhinitis and bronchial asthma. The main pollen season was defined taking the days registering 95% of the total annual pollen, and by studying the fluctuations between years and seasons in terms of Olea pollen at the different sampling points. Correlation analysis showed that the pollen concentrations on the preceding days, as well as the average accumulated temperature, were the parameters that invariably had significant correlation indices at all sampling points. In addition, the forecast models indicated that these two variables, together with others, predicted a high percentage (up to 80% in Jaén) of the seasonality of this pollen observed in the atmosphere of the different localities studied.

The effect of meteorological parameters on diurnal patterns of airborne olive pollen concentration

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.

The effect of air temperature on the starting dates of theUlmus, Platanus andOlea pollen seasons in the SE Iberian Peninsula

A study is made of the effect of air temperature on the start of the pollen seasons of three tree species—Ulmus, Platanus andOlea—in the southeastern Iberian Peninsula. These initial results are based on an aerobiological analysis performed over a 4-year period in the city of Granada, Spain. Sampling was carried out with a Burkard spore trap. The main aim of the present study was to use regression analysis to identify the preseasonal date when these species start to accumulate heat in their floral buds, enabling models to be created that indicate the onset of the pollen season for these taxa. ForUlmus there was no significant correlation between the onset of pollination and the mean temperature during the preceding period, whereasPlatanus presented a significant correlation with mean temperature during the month of January, andOlea with mean temperature during the second fortnight in February and the month of March. ForUlmus, the start of the pollen season ranged between 30 January and 8 February; forPlatanus, between 13 and 17 March; and forOlea, between 20 April and 13 May. The accumulated temperature needed to induce the onset of flowering ranged between 121 and 256°C forUlmus, with values of 428–607°C and 656–881°C forPlatanus andOlea, respectively.

An aerobiological study of Urticaceae pollen in the city of Granada (S. Spain): Correlation with meteorological parameters

An aerobiological study was made of Urticaceae pollen in the city of Granada, relating the mean values of the daily counts to meteorological parameters. Sampling was carried out with a Burkard seven‐day‐recording spore trap from October 1992 to September 1997. This pollen type has an extremely long main pollen season (MPS), with maximum counts in (January) February, March and April, causing numerous cases of human pollinosis throughout the entire Mediterranean region, including Granada. A highly constant intradiurnal variation pattern was obtained showing that the maximum peaks usually occur between 12.00 and 20.00. According to Spearmans correlation coefficient, during the pre‐peak period the parameters which have the greatest effect on the levels of this type of pollen are daily and accumulated temperature and sunshine, accumulated rainfall, and wind direction from the third quadrant; during the post‐peak period these same variables presented significantly negative coefficients. Daily rainfall and rela...

Medieval landscapes in the Spanish Central System (450-1350): a palaeoenvironmental and historical perspective

This paper presents a long-term synthetic overview of the socio-ecological dynamics responsible for the shaping of present-day rural landscapes in the Spanish Central System. Available historical and palaeoenvironmental records have been compiled and cross-referenced to characterise key transformations unfolding in this mountainous macro-region during the medieval time span. A sharp deforestation of upland pines and midland oaks was due to extensive Late Antique strategies. Pre-tenth-century trajectories are diverse and exhibit the recovery of high-mountain pine forests and highly localised agro-pastoral impact on selective mid-altitude niches. The eleventh-century early repopulation policy implied migrations, increased momentum of rural village foundation and extension of colonised agrarian landscapes in the tablelands of the Extremadurii. The pace and intensity of these phenomena depended on ecological and historical circumstances, leading to subsequently different realities. By the mid-thirteenth century the definitive pacification and the rising demographic trend facilitated the later permanent occupation and the ensuing integral and sustainable exploitation of the highlands – and especially the Transierra – within the feudal system. High-altitude landscapes exhibit intensive forest clearances due to transterminant livestock movements and the benefit of seasonal resources, whereas low-altitude settings specialised in arboriculture and diversified crops to supply urban markets.

Airborne grass pollen in Granada (Spain)

We have carried out a study on the annual and daily pollen concentrations from Gramineae over four consecutive years in the atmosphere of Granada (Spain). Samples of pollen grains were collected by the volumetric method with the aid of a Burkard sporetrap. Gramineae, according both to their high sensitizing capacity and to data from allergologists, are responsible for many pollinoses diagnosed in this area. In this work, daily pollen levels from April to July are monitored and the variations identified are interpreted in relation to meteorological conditions. Results indicated that the highest airborne concentrations of Gramineae pollen were found in May and June, although the beginning and intensity of pollination have been variable during these 4 years.

Analysis of micronutrients in olive pollen

Abstract The micronutrient content [iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), boron (B)] of olive (Olea europaea L.) pollen grains from different sites is studied by means of spectrophotometry and atomic absorption techniques. We compared pollen samples collected from organic olive crops (B1, B2, and B3), cultivated without the use of mineral‐based fertilizers, phytosanitary products or herbicides with samples obtained from crops which had undergone extensive chemical treatment (T1, T2, T3, and T4). The micronutrients detected in the pollen grains analyzed show that large quantities of such chemical products are absorbed by the plant. The importance of Fe should be stressed, since in one of the chemically‐treated samples (T3) levels of 1,484 μg/g dry weight were found to have been incorporated into the structure, while in the control samples the equivalent concentrations ranged between 96 and 450 μg/g dry weight. Similarly, Cu was found to have been easily assimilated by populations which had rec...