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Concentrations of airborne spores of fungi and actinomycetes were investigated from 20 samples collected during the handling of wood chips by using a six-stage fractionating impactor (Andersen sampler). Ten samples were taken on wood chip piles or beside the chip conveyor belts of cellulose factories, and ten samples were taken beside chip conveyor belts in central heating plants of saw mills. The spore exposure level varied from 103 to 106 cfu/m3 air. Wood chips used for cellulose production released large numbers of mesophilic and thermotolerant fungi, especially Aspergillus fumigatus, indicating that spontaneous heating had occurred during the storage. By contrast, heavy exposure to Penicillium species and other mesophilic fungi was characteristic of the handling of fuel chips, which are usually only stored for short periods in saw mills. The greatest spore concentration, 3×106 cfu/m3 air (mainly Penicillium), was measured during the handling of fuel chips stored for four months. Heavy exposur...

The uppermost Eocene Florissant Formation, Rocky Mountains, Colorado, has yielded numerous insect, vertebrate and plant fossils. Three previous comprehensive palynological studies investigated sections of lacustrine deposits of the Florissant Formation and documented the response of plant communities to volcanic eruptive phases but overall found little change in plant composition throughout the investigated sections. These studies reported up to 150 pollen and spore phenotypes. In the present paper, we used a taxonomic approach to the investigation of dispersed pollen and spores of the Florissant Formation. Sediment samples from the shale units containing macrofossils were investigated using light microscopy (LM) and scanning electron microscopy (SEM). The general picture of the palynoflora is in agreement with previous studies. However, the combined LM and SEM investigation provides important complementary information to previous LM studies. While a fairly large amount of previous pollen determin...

Fungal spores and pollens can be dispersed in a number of ways: by animals and insects; by water; by wind or by rain. This paper concentrates on the effects of wind on the dispersal of spores and pollen grains and the effects of rain on spore dispersal. For dispersal to be successful particles must complete three phases: removal, dispersal through the air and deposition. The biology of the organism and its environment can affect all three phases, however, once released the fate of all airborne particles largely depends on the laws of physics which govern the motion of the air. Many types of spore are actively ejected into the air while others are simply blown from the host surface. Particle size and shape affects dispersal and deposition phases. Local environmental factors such as temperature, humidity and light, as well as wind or rain, can play a key role in the removal of spores. Wind speed and turbulence or rainfall, largely determine spore dispersal, but, the size and shape of the particle, ...

The possibility to apply diffusiophoresis and the Stefan flow effects in a new type of sampler was investigated. The advantages of the later are significant compared with other sampler desingns, since it gives representative samples that can subsequently analysed by the methods of optic and electron microscopy. The low particle deposition velocity keeps microorganisms intact, on the other hand, the small depence of the particles' deposition velocity upon their sizes makes the separation of the analyzed aerobiological objects impossible. As a result, the representativness of samples is secured. In this paper the sampler design is described and its working conditions (heat, hydrodynamic) are analyzed.

Records of air-borne pollen and spores were made during a six month period in the Stockholm area in 1972. This paper presents phenological data and volumetric measurements obtained by means of a Burkard trap. Attention was paid to both arboreal pollen and non-arboreal pollen and spores, identified to family, genus or species level. Spores of certain common Pteridophytes were also included in the investigation, but not Bryophytes or fungal spores.