Bijeenkomst: EGF2015
Auteur: Deru J., Van Schooten H., Huiting H. and Van der Weide R.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
Maize (Zea mays) cultivation for silage has negative impacts on soil and water quality: reduced soil organic matter, nitrate leaching, soil-biota decline, etc. These problems can be caused partly by intensive soil tillage, like ploughing. The suitability of less-intensive tillage alternatives for farmers, in terms of effects on yield and soil quality, is unknown. On three field experiments, two on sandy soils and one on marine clay soil, we compared ‘full-field inversion tillage’ with two reduced tillage systems: ‘full-field non-inversion tillage’ and ‘strip-cutter’. Reducing tillage intensity in silage maize cropping influenced both yields and soil quality: at two locations yields tended to be reduced, and at two locations soil organic matter content was lower in inversion tillage compared to reduced tillage. The possible implications of reduced soil organic matter mineralisation for nitrogen dynamics are discussed.
soil organic matter
Capacity of the soil to decompose organic matter in old and young grasslands
Bijeenkomst: EGF2015
Auteur: Iepema G.L., Domhof B. and Van Eekeren N.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
To study the effect of grassland renewal on soil quality and the eco-efficiency of grass production, we compared ten young grasslands (aged 5-10 years grassland without tillage) with ten old grasslands (age >20 year grassland without tillage) as pairs on ten dairy farms on marine clay in the North of the Netherlands. On these 20 grasslands we measured the capacity of a soil to decompose organic matter. This was tested by using the Tea Bag Index (TBI). TBI is determined through the burial and retrievement of green and rooibos tea bags, following by the measurement of mass loss after 90 days. The decomposition rate k and the stabilisation factor S of young grasslands were not significantly different from older grasslands; however, variation between locations was high. A negative correlation was found between age of the grassland and the stabilisation factor S, meaning that decomposition of organic matter in older grassland continues for a longer time and may be an indication of a higher soil biological activity.