Moving beyond manure

Strong intensification of animal and crop production systems in the past 50 years has led to disintegrated farming systems resulting in displacement of crop and livestock farming and higher environmental impact. Manure and fertilizer management are key areas in the related environmental impact of modern farming systems. Innovations in crop and animal production systems, such as anaerobic digestion of manure for energy production and processing of manure into liquid fertilizer, have emerged, which can partly counter negative environmental side effects. However, little research has been done on the integration of measures addressing more managerial aspects and including multiple environmental effects in the chain from animal to crop.

This research aims at improving the environmental performance through reductions of nitrogen, phosphorus and carbon emissions, in the chain from animal to crop by tailoring manure products and management and soil management tot crop production needs (Figure 1). Managerial aspects included in the study are: manure product and quality, application amount, timing, placement and application technology and soil tillage.

By setting environmental goals and by using a methodical approach to engineering design, new chains from animal to crop and management approaches are designed aiming at low environmental impact. Life Cycle Assessment (LCA) is applied as a methodology to quantify the environmental consequences of these designed chains. Environmental indicators included in the assessment are greenhouse gas emissions, acidification potential, eutrophication potential, fossil fuel depletion and particulate matter formation. Lacking emission data are assessed in experiments. A field experiment will be conducted to obtain information on greenhouse emissions and the effect of soil tillage combined with application of different manure products.

Final results of the research give essential insight in the environmental consequences of applying several manure and soil management techniques in the chain from animal to crop.