The dustiness of the air on the farm is most often associated with wind erosion of the soil, and also with the harvest season. Wind erosion is the adverse phenomenon of soil being blown away from a field by the wind; it can be associated with both entrainment of poorly bonded soil particles (sprayed, over-dried soils with low soil aggregate content) and cultivation errors.
Counteracting this comes down to taking appropriate agrotechnical measures. In general, all treatments to improve soil structure counteract erosion. It is also important to limit the number of passes over the field, and especially to eliminate passes when the soil is very wet, as this destroys the aggregate structure of the soil. Tillage operations should also not be carried out when the soil is too dry, as this causes dusting (raising soil particles into the air).
Oilseed rape and cereal harvesting takes place in late summer and autumn and should be carried out under low humidity conditions. This results in a high degree of fragmentation of dry plant parts and the generation of significant amounts of dust. A source of very high airborne dust can be the harvesting of crops that are overgrown and additionally infected with fungal diseases. In this case, the dust contains, in addition to plant tissues, aerosolised soil and huge quantities of fungal spores, mainly from the Cladosporium and Alternaria families, which can have implications for human health.
Nor should the dustiness of the air generated by storage, production and preparation of feedstuffs, and by smoke emissions from the combustion of solid fuels and crop residues be underestimated, as it contains very fine dust (PM 2.5). Air quality in small towns and villages is sometimes worse, especially during the heating season, than air quality in large cities.
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