Meteorological impacts on pollen emission and spread - Introduction to an interdisciplinary project

Turku

2008

S. 39

Unselbständiges Werk

200149021

Emission and spread of tree polten are important processes, firstly, because pollen of several tree species act as major allergen in the human population, and secondly, because pollen dispersal is a crucial process in the life cycle of the predominantly wind-pollinated trees in temperate forests. Thus, pollen dispersal provides reproduction and gene flow, and contributes significantly to the genetic diversity within and among populations. The present poster introduces a new project that aims at investigating and highlighting the meteorological factors causing local pollen emission and transport in a typical Central European forest of mixed deciduous and coniferous trees, and the development of a functional model for pollen emission. We conduct measurements of pollen concentrations of spring flowering trees and meteorological conditions in a high-temporal resolution at three levels on a 30 m high tower within a 20 m high forest canopy in the "Lehrforst Rosalia" in Eastern Austria. The Instrumentation consists of a special adapted pollen collector with three sampling units, which sample pollen from all directions in the same quantity, and which allow the recording of pollen concentration in a high temporal resolution. The meteorological equipment consists of three Ultrasonic anemometers and conventional temperature, humidity and radiation sensors, which measure meteorological data in the same heights as the pollen concentrations (above the canopy, within the canopy, and on the forest ground). In addition to the field campaign, pollen transport will be modelled with a Lagrangian particle model based on trajectories determined from a diagnostic wind field model fed also by the meteorological data of surrounding stations. The project should improve knowledge on: a) pollen emission with respect to different tree species common in Central Europe, b) the meteorological parameters favouring pollen emission, c) the horizontal and vertical pollen transport within and above the forest canopy, and d) the ability of a Lagrangian particle model to correctly estimate ambient pollen concentrations. The expected better understanding of pollen emission and spread of typical European forest tree species will help to develop a new generation of pollen dispersal models. Such models can be important tools for forest research and landscape management, for forecasting and monitoring of pollen allergy Symptoms, and for a risk evaluation and monitoring of genetically modified trees.