A key challenge for sustainable intensification of agriculture is to produce increasing amounts of food, feed and bioenergy for a growing world population, with minimal loss of ecosystem functioning. Soil organic matter plays a key role in this multifunctionality. However, there are still important questions to be solved, such as how much organic matter needs to be returned to the soil of what quality, and how to prevent a yield gap of a more organic versus conventional agriculture. In organic farming systems, fertilizing soil with only organic matter inputs may result in lower nitrate leaching, but this type of management also leads to lower crop yields. In this project, we investigate the transition of conventional to a more organic management, aiming at finding conditions where soil conditions favour both high crop yields and minimal impacts of farming on the environment. Especially, we are interested in how key soil chemical, physical and biological properties change over time as a result of a transition from conventional to organic farm management. We established a chronosequence, consisting of a series of farmers fields that have been converted from conventional to organic farming for various time periods, and study changes that have taken place in these fields relative to nearby conventionally managed fields. We test the hypothesis that organic farm management enhances nutrient retention governed by the soil food web due to higher C:N organic matter inputs compared to conventional farm management. Furthermore, we test the hypothesis that a substantial amount of organic matter is protected in aggregates that, when disrupted, cause the labile components to be mineralized, thereby increasing bioavailability of plant nutrients. In order to reduce nutrient leaching, restoration of aggregate formation after disruption is important. The final goal of our project is to inform about potential management practices that may help to shorten the transition period from conventional farming to a more organic type of farming that maintains high crop yields while having less negative environmental impacts.
|Publication status||Published - 2017|
|Event||EGU General Assembly 2017 - Vienna Austria|
Duration: 23 Apr 2017 → 28 Apr 2017
|Conference||EGU General Assembly 2017|
|Period||23/04/17 → 28/04/17|