Biodiversity and multifunctionality in the Ossekampen long term grassland fertilization experiment (KB-36-004-014)

In the years after the Second World War agriculture in the Netherlands showed tremendous changes. Drainage, reseeding, fertilization, mechanization, and new methods of fodder conservation resulted in an increase in grassland productivity, affecting grassland biodiversity. Semi-natural grasslands were improved and re-sown with highly productive varieties. Dutch grassland scientists - Prof ML ‘t Hart and Prof DM de Vries - were aware of the rapid decrease in plant diversity of semi-natural grassland and took the initiative to establish an experiment, following the example of the ‘Park Grass Experiment’ at Rothamsted. In the first instance they wanted to improve the low productive grasslands, but at the later stage they wanted to maintain the botanical diversity and soil quality. The Ossekampen Grassland Experiment was established in 1958 on a species-rich old pasture on heavy clay soil near Wageningen, the Netherlands, to track productivity and plant species shifts under long-term application of inorganic fertilizers and lime at extensive haying or grazing management. Fertilizers were applied annually as a single nutrient: N, P, K or Ca, or in combinations: PK, NPK and PK+N (Korevaar & Geerts, 2015) on two replicates.

Since its establishment the management of the cutting experiment remained unchanged with two cuts a year. In 1986 the P and K fertilization was reduced to achieve a better nutrient balance. Due to this long term stable management we can assume a certain stability of the ecosystem in response to the different fertilizer treatments. Therefore the Ossekampen experiment provides us with the unique opportunity to assess long term effects of different fertilization levels on biodiversity and the provision of ecosystem services.

 

Here we propose an intensive multi-disciplinary one-off measurement campaign, during the 2022 growing season, on soil and plant indicators of biodiversity and ecosystem service delivery. The campaign is a joint initiative of WUR research groups and chairs, Amsterdam University, Utrecht University, NIOO and LBI.