Long-term opportunities and risks of using biochar in soils: Analysis of changed soil fertility parameters, C storage behaviour and ecotoxicological and environmental effects (PK-BODENABC)

The aim of the PK-BODENABC project is to characterize long-term changes in soil more than 10 years after the introduction of biochar (PK) at four different locations with soil properties ranging from sandy to loamy to clayey in order to answer the question of whether additive soil carbon storage occurs and whether positive or negative effects are to be expected in the long term: The investigations focus on a number of soil fertility parameters (soil biological and physico-chemical parameters) and on any additional soil C storage over the past decade via the PK administration beyond; and exemplarily on the C retention of fresh assimilate in ‘old’ PK soils (13C pulse labeling-tracing). In addition to the influence on C storage, it should also be quantified whether the nitrogen (N) losses (e.g. nitrous oxide, nitrate) in these soils are reduced in the long term. In the project, ISO and OECD standardized terrestrial and aquatic ecotoxicological tests are used to test the effects on soil fauna (reproduction tests) and the leaching ability of plant protection products that are applied in pulses and are commonly used in agriculture, which can normally get into ground and surface water and according to the current state of knowledge, PK soils may be better retained, which should be visible in the effects on soil and aquatic fauna.