تأثير نوع معدن الطين و الحالة البنائية في المحتوى الرطوبي للتربة في ظروف الترطيب و التجفيف

الملخص EN

The study was carried out to show the effect of the clay characteristics: specific surface area (Ss), cation exchange capacity (CEC), and the assemblage of clay particles on the soil water content.

The effect of hydric stress history (wetting and drying cycles) on the water content of soil was also investigated.

Soil samples comprising topsoil horizons and subsoil horizons, with a clay content > 30% were collected in several regions of France and Syria (2009 - 2012) in cooperation with the National Center for Scientific Research and the University of Orléans in France to study the effect of physical characteristics on the fertility status of the soil.

The water retention properties were studied from (0.01) bar to (15) bar water potential using small clods collected in winter when swelling is at a maximum and water content close to field capacity.

The clay content, the bulk density of horizon and clods, the cation exchange capacity and the specific surface area were measured.

The X-ray diffraction (XRD) was used for identification of the main mineralogical phase, and to study the relationship between the clay mineralogy and the water retention.

Results showed that the variation of the soil water content was explained by the differences of clay content and the clay fabric (assemblage of clay particles).

The results also showed that wetting and drying cycles were the most important and critical factor for soil water retention properties relative to the other evaluated factors