permanent grassland

Bijeenkomst: EGF2015
Auteur: Verloop J., Oenema J. and Geerts R.H.E.M.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
The objective of this study was to explore under farming conditions the effect of reduced fertilizer N application rates on the dynamics of botanical composition and yields of grass-clover-swards. In both temporary and permanent grassland the percentage of highly productive grasses (good grasses) declined at a constant rate of 3.0 to 6.3% points y‑1 during the aging of the sward. Good grasses were replaced by less-productive grasses and herbs. The percentage of clover did not show a significant trend. Reduced N fertilization did not significantly change these dynamics. The percentage of white clover and, in some cases, high-yielding grasses in the sward, enhanced the yields of nitrogen and herbage dry matter, while the percentage of herbs reduced yields.

Bijeenkomst: EGF2015
Auteur: Vintu V., Samuil C., Saghin G. and Stavarache M.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
In the mountainous region of Romania about 200,000 ha is covered by grassland, which is mainly dominated by Nardus stricta L. We have studied the influence of mineral fertilization on productivity, canopy composition and forage quality of Nardus stricta L. permanent grassland in the intra-mountainous depression of Vatra Dornei (North-Eastern Carpathians, 820 m.a.s.l.). Fertilisation was applied at rates of N100-200 P100-200 kg ha‑1 in one or several applications. These mineral fertilizer rates resulted in changes in the dominant species of Nardus stricta L. grasslands, by increasing the percentage of Festuca rubra L. and Agrostis capillaris L. Productivity increased by 119-224%, as well as forage quality compared to the unfertilized control.

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.