Medium- and long-range transport events of Alnus pollen in western Mediterranean.

Alnus pollen has been frequently detected in the atmosphere of different airborne sampling sites of Southern Spain. However, Alnus sp. populations are very scarce and fragmented in the area, being restricted to a few river valleys in the southwest, and other further away regions of the Iberian Peninsula. This leads to think that the airborne pollen detected could be mainly the result of a medium- or long-distant transport. So, the aim of this study was to characterize the annual patterns of airborne Alnus pollen detected at three different locations of Malaga province, as well as to determine its possible origin, the pollen dispersion potential of these Alnus isolated populations, and their possible reproductive connectivity. Pollen sampling was conducted by means of three Hirst-type volumetric pollen traps. Samples were mounted and counted following the recommendations of the Spanish Aerobiology Network and the European Aeroallergen Society. The possible pollen sources were detected by means of a combination of meteorological information and backward air trajectories analysis. A high inter-annual variability in the annual pollen integrals was found in all the stations, favouring certain meteorological conditions a long-range transport and, therefore, causing the high concentrations detected in some specific days. Alnus pollen seems to have a heterogeneous origin with prevalence of the long-distant transport, which would suggest a possible reproductive connection among distant populations.

Effect of meteorological parameters on Poaceae pollen in the atmosphere of Tetouan (NW Morocco).

Poaceae pollen is one of the most prevalent aeroallergens causing allergenic reactions. The aim of this study was to characterise the grass pollen season in Tetouan during the years 2008-2010, to analyse the effect of some meteorological parameters on the incidence of the airborne Poaceae pollen, and to establish forecasting variables for daily pollen concentrations. Aerobiological sampling was undertaken over three seasons using the volumetric method. The pollen season started in April and showed the highest pollen index in May and June, when the maximum temperature ranged from 23 to 27 °C, respectively. The annual pollen score recorded varied from year to year between 2,588 and 5,404. The main pollen season lasted 114-173 days, with peak days occurring mainly in May; the highest concentration reached 308 pollen grains/m(3). Air temperature was the most important meteorological parameter and correlated positively to daily pollen concentration increase. An increase in relative humidity and precipitation was usually related to a decrease in airborne pollen content. External validation of the models performed using data from 2011 showed that Poaceae pollen concentration can be highly predicted (64.2-78.6 %) from the maximum temperature, its mean concentration for the same day in other years, and its concentration recorded on the previous day. Sensitive patients suffering allergy to Poaceae pollen are at moderate to highest risk of manifesting allergic symptoms to grass pollen over 33-42 days. The results obtained provide new information on the quantitative contribution of the Poaceae pollen to the airborne pollen of Tetouan and on its temporal distribution. Airborne pollen can be surveyed and forecast in order to warn the atopic population.

Variations and origin of the atmospheric pollen of Cannabis detected in the province of Tetouan (NW Morocco): 2008-2010.

Cannabis, also called marihuana or hemp, is a wind-pollinated plant that produces hundreds of flowers on large inflorescences. It is also one of the oldest psychoactive plants known to humanity. Morocco has become one of the main producers of Cannabis resin (hashish), primarily supplying the European market. The aim of this paper is to ascertain whether the atmospheric monitoring of Cannabis pollen can play a role, from a criminological point of view, in the surveillance of Cannabis cultivation in the area of Tetouan (NW Morocco) as well as to estimate pollen emission so that the sensitive population can be warned about the allergic diseases that its pollen can cause. Aerobiological samplings were made with the aid of a Hirst type volumetric trap (Hirst, 1952), which worked uninterruptedly during a 3-year period (2008-2010) according to the methodology proposed by the Spanish Aerobiology Network, the REA. Cannabis pollen was present in the atmosphere of Tetouan mainly from early April to late August, a period in which about 95% of the annual counts were registered. The highest levels were detected in June and July, with concentrations more or less evenly distributed throughout the day with slight increases of 5% between 12:00 and 16:00 h. The strong association between skin test reactivity, respiratory symptoms, and pollination period found by other authors, together with the levels registered, suggests that Cannabis pollen could be a clinically important aeroallergen for sensitive patients. On the other hand, the data obtained could serve as an indicator of the cultivation activity of this species and should be taken into account by the state authorities since they provide strong evidence of the existence of Cannabis crops in the region of Tetouan.

A three-year aeropalynological study in Estepona (southern Spain).

An aeropalynological study was carried out in the atmosphere of Estepona, a very popular tourist resort situated in the "Costa del Sol", (southern Spain) based on the data obtained during a three year air-monitoring programme (March 1995 to March 1998) using a volumetric pollen trap. The 34 taxa that reached a 10-day mean air pollen concentration equal to or greater than 1 grain of pollen/m(3) of air are reflected in the calendar. The first 10 taxa, in order of abundance, were: Cupressaceae, Olea europaea, Quercus, Poaceae, Urticaceae, Plantago, Pinus, Chenopodiaceae-Amaranthaceae, Ericaceae and Castanea, the first 3 of which accounted for approximately 56 % of the annual total pollen count. The greatest diversity of pollen type occurred during spring, while the highest pollen concentrations were reached from February-June, when approximately more than 80 % of the annual total pollen was registered. The lowest concentrations were obtaining during January, August and September. The annual quantity of pollen collected, the intensity and the dates on which the maximum peaks were recorded differed for the 3 years studied, which can be explained by reference to various meteorological parameters, especially rainfall and temperature. The pollen calendar spectrum is typically Mediterranean and similar to those of nearby localities, in which many pollen types are represented and the long tails indicating long flowering periods.