Soil fertility, nutrient cycling and composting

In the optimization of cultivation systems in organic farming, studies on the improvement and sustainable maintenance of soil fertility and on farm and regional nutrient cycles, particularly in the application of organic fertilizers, take on a major focus. In this context, we also focus in many cases on crop management system approaches for organic farming in three-year research projects, which, for example, take into account both the effects of fertilization measures on the main crop and the subsequent crop in order to investigate longer-term effects for the stabilization of yields.

Projects on composting and compost application of cattle manure and clover grass at the on-farm level, or biosolids and green waste composts from separate collection of organic household waste when considering regional nutrient cycles and their effects on plant health, yield, and soil fertility, have a long tradition at the department. In a long-term experiment, which has been set up on the Frankenhausen domain since 2017, various crop rotations in livestock-less and low-livestock farming systems in organic farming are being investigated; the effect of management and fertilization measures on greenhouse gas emissions occupies an important place.

Greenhouse gas measurements and the closing of nutrient cycles are also the subject of the KLUFT project, which, in cooperation with practitioners, deals with the closing of cycles in the free-range rearing of laying hens, as well as the topic of intercropping currently being worked on by the specialist group for arable farming in the Hesse Practice Research Network. In particular, the long-term trial is a platform for interdisciplinary work on the issues with integration of soil chemistry, soil physics and soil biology expertise beyond the specialist field.

• Ruch, B.;Hefner, M.; Sradnick, A. Excessive Nitrate Limits the Sustainability of Deep Compost Mulch in Organic Market Gardening. Agriculture 2023, 13, 1080. https://doi.org/10.3390/agriculture13051080
• Hupe, A., Naether, F., Haase, T., Bruns, C., Heß, J., Dyckmans, J., Joergensen, R.G., Wichern, F., 2021. Evidence of considerable C and N transfer from peas to cereals via direct root contact but not via mycorrhiza. Scientific Reports 11, 11424. https://doi.org/10.1038/s41598-021-90436-8
• Döring, T.F., Rosslenbroich, D., Giese, C., Athmann, M., Watson, C., Vágó, I., Kátai, J., Tállai, M., Bruns, C., 2020. disease suppressive soils vary in resilience to stress. Applied Soil Ecology, 149, 103482. https://doi.org/10.1016/j.apsoil.2019.103482
• Jannoura, R., Joergensen, R.G, Bruns, C., 2014. organic fertilizer effects on growth, crop yield, and soil microbial biomass indices in sole and intercropped peas and oats under organic farming conditions European Journal of Agronomy 52:259-270. https://doi.org/10.1016/j.eja.2013.09.001
• Hagn, A., Engel, M., Kleikamp, B., Munch, J.C., Schloter, M., Bruns, C. 2008. microbial community shifts in Pythium ultimum-inoculated suppressive substrates, Biol. Fertil. Soils 44: 481-490, https://link.springer.com/article/10.1007/s00374-007-0230-x