Effects of farmyard manure application on dust emissions from arable soils

Abstract

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.