الفهرس | Only 14 pages are availabe for public view |
Abstract 1. Introduction Soil degradation is a serious problem that concerns more than 15% of the landmass. Arable lands are the most affected land by the aspect of soil degradation. El-Husseiny (2011) reported that; in Egypt, the agricultural area is very limited and it does not exceed 3% of the total country area. This area is subjected to reduction due to various natural causes or anthropic activities. In North-Western Coast region, the most promising area for agricultural expansion, the cultivated areas is exposed annually to intensive rainstorms, which affect the main soil properties and crop productivity. Rainfall-induced surface sealing which forms as a result of the impact of the occasional heavy rainfall events on unprotected soil surface, causes many negative effects on infiltration, water holding capacity, soil aeration, overland flow, nutrient losses, and seedling emergence (Assouline, 2004). Because of these unavoidable damages, surface sealing is a very serious soil degradation factor which threatens calcareous soils (Morin, 2003). Many studies investigated soil surface sealing from different points of view. However, assessment of sealing impacts on soil and environment needs further investigations. The current work aims at evaluating calcareous soils surface sealing and assessing surface seal impacts soil characteristics and seed germination. 12 |