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Soil ecological engineering and management of soil biology. <BR>A contribution to achieving zero hunger? (Communication session)

EUROSOIL2020CONT-2393

DO EFFECTIVE MICROORGANISMS (EM) AFFECT THE TRANSFORMATION OF ORGANIC MATTER? RESULTS OF A SOIL INCUBATION EXPERIMENT.

Christa Herrmann^{* 1}, Adrien Mestrot¹, Simon Oberholzer², Markus Steffens^{1, 3}, Klaus Jarosch¹

¹Institute of Geography, Soil Science, ²Institute of Geography, Sustainable Land Management, University of Bern, Bern, ³Soil Science, Climate group, FIBL, Frick, Switzerland

Content: The application of effective microorganisms (EM) on agricultural fields has become increasingly popular during recent years. Producers of EM promise a faster decomposition of plant material and improved soil quality as a direct or indirect effect after EM application on the field. In practice, farmer apply EM to the green manure shortly before its shallow incorporation into the soil. Here, EMs are assured to increase the mineralisation of the recently incorporated plant material, followed by a subsequent microbial immobilisation of the thereby released nutrients. These nutrients are promised to become available again for the following crop. However, empirical evidence on the effectiveness of EM application on soils and their subsequent effect on soil parameters is scarce.

For that reason, we are performing a soil incubation experiment on loamy Cambisol. During the soil incubation experiment we determine the effects of a commercially available and commonly used EM-mixture added to a soil with fresh green manure addition. Over a 4-week period we assess the concentration of labile organic carbon (permanganate oxidizable carbon), microbial biomass (microbial bound carbon) and soil microbial activity (soil respiration) at different levels of EM addition and soil temperatures. Additionally, water-extractable mineral nitrogen and phosphorus as well as potentially toxic trace elements (PTTEs) are monitored. The results of this study will contribute to an improved understanding if the application of EM is affecting the transformation of recently added plant material and how microbial processes are affected by EM addition into soil.

Disclosure of Interest: None Declared

Keywords: effective microorganisms, Labile organic carbon, organic matter decomposition, Soil microbial biomass, soil organic carbon, Soil respiration, Sustainable Land Management