Earthworm activity improves soil fertility. In arable crop rotations highest earthworm populations are usually found in leys. The impact of tillage system and tillage intensity on earthworm populations was studied in the two long term trials at urgrain (Albertswil LU) and at Hausweid (Aadorf TG). At Burgrain having a crop rotation lasting six years and including a ley, no significant difference of earthworm biomass was found between ploughed plots and plots with in the sampling period 2004 – 2008 in the tillage system usingminimum tillage (mulch drilling for oilseed rape and sowing with a rotary band cultivatorrotary band seeding for silage maize) (IP extensive) compared to ploughing in both, the organic as well as the integrated production (IP intensive). In contrast, at Hausweid having a four years crop rotation at Hausweid without ley, earthworm populations differed significantly depending on tillage system and tillage intensity after 21 years of the trial. Earthworm biomass reached 330 g per m² in the permanent grassland adjacent to the trial whereas it was reduced by 50 % in the no-till and even by 80 % in the ploughed plots. dditionally, average earthworm species diversity in permanent grassland and no-till was 30 % higher than in ploughed tillage system. These findings confirm the positive impact of no-till on the increase of earthworm populations and species diversity.
The reduction of environmental risks from plant protection products is to be monitored by the Confederation using a risk indicator. The indicator also takes into account the degree of implementation of risk reduction measures in practice. This degree of implementation was estimated by a study.
Arbuscular mycorrhizal fungi are important for healthy soils and crops. A pan-European study shows that plant-protection products adversely affect these fungi, reducing their ability to supply plants with phosphorus via their roots.
A comparison of different methods of winter-wheat fertilisation with nitrogen showed that nitrogen surpluses can be significantly reduced by means of site-specific variable-rate nitrogen fertilisation.