Climate change, drought, erosion, water contamination resources, desertification, and loss of soil quality represent major environmental risks worldwide. Facing these risks is the most important issue for sustainable development. Conventional tillage (CT) practices seem to expose the soils of semi-arid regions, which are initially fragile, to degradation that is accentuated by the overuse of the environment. The benefits of conservation agriculture (CA) could mitigate the degradation of natural resources, particularly soils. The adaptation and transfer of the no-till (NT) system with mulch open new perspectives for the development of agriculture in semi-arid regions. The main objective of this study is to assess the impact of conservation agriculture, especially no-till (NT) system, on the physical properties of soil (structural stability (SS), bulk density (BD), gravimetric water content (θg), and soil organic matter (SOM)) compared to conventional tillage (CT). The main changes associated with the transition from a CT system to an NT system were evaluated at the experimental site, Merchouch (M13), which is typified by vertisol soil, and at the Ain Sbit (AS7) site, which is characterized by isohumic soil. Under a no-till system, most of the physical properties of the soil were improved in both sites, with a clear difference in the M13 site. Structural stability under NT showed a significant increase in both sites (fast wetting (FW), slow wetting (SW), and wet stirring (WS) improved by 88, 43, and 83% at the M13 site, respectively, against, 16, 23, and 7%, respectively, at the AS7 site). On the other hand, the SOM increased from 2.0 to 2.6% (an improvement of 28%) at AS7 and from 1.2% to 1.9% (an improvement of 52%) at M13. This research demonstrated that conservation agriculture, especially NT, improves the soil physical quality in both medium and long terms, confirming its suitability for the climatic and edaphic constraints of semi-arid areas in Morocco as well as in other parts of the world.

Tetraclinis articulata (Vahl.) Master or thuya is facing several constraints to its successful natural regeneration in Morocco. Containerized seedlings plantation is the only method adopted in thuya forest restoration programs and post-transplant water stress produces high seedling mortality after the first summer following outplanting. There is thus a real need to improve nursery seedlings quality, especially enhancing the growth of the root system by improving the water holding capacity of the root plug. Our aim was to assess the effects of clay on the water holding capacity of the growing media and on various morphological and physiological traits of T. articulata seedlings in the nursery. T.articula seedlings were raised in nursery using nine composite substrates; seedlings quality was evaluated according to their morpho-physiological and performance attributes. This investigation determined that a clay content of 20–25% constitutes an optimum for obtaining seedlings with a good root growth potential and high root viability. Excessive clay content in the growing media resulted in water-logged root plug decreasing root growth potential. This investigation found that morphological attribute as Root Collar Diameter and Root/Shoot ratio could be considered good predictors of Root Growth Potential.