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Particulate matter (PM), emitted during agricultural activities, could be a source for the atmospheric dispersal of pathogenic or antibiotic resistant bacteria when agricultural fields are fertilized with contaminated manure. The use of contaminated bedding material from chicken breeding as farmyard manure can initiate a releasing process for resistant bacteria into the environment. In this study, we focus on the physical processes of the release, regarding application and manure mixtures. The addition of several tons per hectare of organic manure to the topsoil has effects on the soil composition and should effect the dust emissions, if the same sorting effects are assumed such as for other organic particles. Based on dust measurements within an agricultural process chain from manure application, soil preparation to maize seeding, dust emissions were measured and PM10 emission factors (PM10 EFs) were derived using a standard dispersion model. The PM10 emissions during manure application ranged between 0.05 and 8.37 kg/ha, depending on the moisture content due to different pretreatments of the manure. In the subsequent tillage operations, a share of 0.39–0.59% of manure in the total PM10 could be determined. Our investigations show that particles in the PM10 fraction of manure origin are released within the entire process chain. These particles are small and light enough to be transported over long distances and be a potential risk for antibiotic resistant bacteria dispersal at remote places as human settlements, when they will deposit there.

Open-cast lignite mines are sources of PM- emissions, caused by mining activities and wind erosion on the large bare deposition areas. PM10- and PM2.5-emissions of these technogenic materials have not been determined in detail so far, but are needed for emission cadastres or in dispersion models at the local scale In wind tunnel experiments substrates from the four active mines in Lower Lusatia in eastern Germany were investigated to estimate PM10- and PM2.5-emissions. The substrates include the cover layers and the lignite seams. Two experimental approaches were compared to relate the PM- emissions of the substrates to the main releasing mechanisms and substrate characteristics. The results show that lignite and lignite containing substrates emit distinctly higher amounts of PM10 and PM2.5 than mineral substrates, regardless of the releasing process. The estimated PM-emission potentials (PM-EP) ranged between 5 and 650 µg g−1 for PM10 and between 2 and 44 µg g−1 for PM2.5 and are correlated to the dry sieving fraction The highest PM- emissions per m2 occur together with the highest transport rates, although the materials themselves have low PM-EP. A distinct higher rate is emitted from lignite samples and substrates permeated with lignite. Wind erosion increases the PM10- emissions to 360 per cent and the PM2.5-emissions to 270 per cent of the PM-EP. The PM10- emissions of the mineral substrates are close to the potentials and heterogeneity of the materials has also an increasing effect.

Wind erosion is known to be a gradual process of soil degradation on arable lands. Poultry manure fertilization is a common practice to improve physical, chemical and biological soil properties, and is thus an essential part to maintain soil fertility. Shortly after incorporation, poultry manure and soil particles are loosely adjacent without any bonding. This supposedly affects the susceptibility of soils to wind erosion and influence the physical and chemical composition of the wind-eroded sediment. Wind tunnel experiments were conducted with three wind speeds (8, 11, 14 m s−1) and four sandy soils, each fertilized with poultry manure in a common rate of 6 t ha−1. Incorporation of manure in the soils changed the particulate organic matter (POM) composition resulting in increased median particle diameters, carbon contents and hydrophobicity. Wind erosion caused a preferred release of manure particles already at wind speeds close above the threshold of 7 m s−1 with the greatest sorting effects in size, shape, and density of the particles. Thus, wind erosion immediately leads to losses of the added organic material. At higher wind speeds the sediment composition rather corresponds to the entire soil or soil-manure mixtures. Depending on the wind speed and total soil loss, potential manure losses between 101 and 854 kg ha−1 were accounted, which are 1.7–14% of the fertilization rate. The results indicate a risk of substantial loss or redistribution of poultry manure by wind erosion immediately after incorporation.