Localisation

The field experiment is situated on the Alluets le Roi plateau in Feucherolles around 30 km west of Paris, in Yvelines (department 78) nearby the INRA Versailles-Grignon and  VERI based in Limay (Figure 1).

Figure 1. QualiAgro field experiment localisation

The plateau is made up of Fontainebleau sand and sandstone (50 à 60 m) topped by a fine layer of burstone clay  3 à 7,5 m)  and covered by a deposit (2 m) of carbonate loams of a windblown origin called loess. This loess constitutes the initial geological support for the development of the pedological cover. The soil is a leached loamy type of a depht greater than 1.2 m (Luvisol acconding to the French pedological reference system dated 1995). It develops based on loessic carbonate loam, which appears at around 1.60 m (Figure 2).

Figure 2. Soil profile

The initial organic matter content of the soil was 1.7%, which is close to the critical threshold of 1.5% for this type of soil.
The soil has a loamy-clayey texture, is associated with an unstable structure and is vulnerable to surface crusting (index of 2.4).
Without regular heating, the soil tends to become acidic.
Concentrations of trace metal elements (TME) are fairly low compared with those of cultivated soils in the same region.

Annual average precipation is 583 mm and the annual average temperature is 11°C (data recorded on the site's weather station).
The normal seasonal data indicated by Météo France for the geographical area during the 1971-2000 period are as follows:
- Annual average precipitation of 695.5 mm (119 days of precipitation)
- Average minimum daily temperatures of 6.8°C
- Average maximum daily temperatures of 14.7°C.