Stabilizing or improving soil organic carbon content is essential for sustainable crop production under changing climate conditions. Therefore, soil organic carbon research is gaining momentum in the Mediterranean basin. Our objective is to quantify effects of no tillage (NT) and conventional tillage (CT) on soil organic carbon stock (SOCs) in three soil types (Vertisol, Cambisol, and Luvisol) within Central Morocco. Chemical analyses were used to determine how tillage affected various humic substances. Our results showed that, after 5 years, surface horizon (0-30 cm) SOC stocks varied between tillage systems and with soil type. The SOCs was significantly higher in NT compared to CT (10% more in Vertisol and 8% more in Cambisol), but no significant difference was observed in the Luvisol. Average SOCs within the 0-30 cm depth was 29.35 and 27.36 Mg ha −1 under NT and CT, respectively. The highest SOCs (31.89 Mg ha −1 ) was found in Vertisols under NT. A comparison of humic substances showed that humic acids and humin were significantly higher under NT compared to CT, but fulvic acid concentrations were significantly lower. These studies confirm that NT does have beneficial effects on SOCs and quality in these soils.

In many parts of the world, the impact of open landfills on soils, biosphere, and groundwater has become a major concern. These landfills frequently generate pollution plumes, the contours of which can be delineated by non-intrusive geophysical measurements, but in arid environments, the high soils resistivity is usually an obstacle, which results in the low number of studies that have been carried out there. In addition, such prospecting using geophysical techniques do not provide information on the intensity of the processes occurring in the water table. This study was carried out on an uncontrolled landfill in the arid Tadla plain, Morocco’s main agricultural region. A survey based on geo-referenced spontaneous potential measurements was combined with measurements of anoxic conditions (Eh-pH and O2 equilibrating partial pressure) in the groundwater and leachates, in order to highlight a pollution plume and its geometry. The range of spontaneous potential measurement is wide, reaching 155 mV. Ponds of leachate with high electrical conductivity (20 to 40 mS cm−1) form within the landfill, and present very reducing conditions down to sulphate reduction and methanisation. The plume is slowly but continuously supplied with these highly reducing and organic carbon-rich leachates from the landfill. Its direction is towards N-NW, stable throughout the season, and consistent with local knowledge of groundwater flow. The fast flow of the water table suggests pollution over long distances that should be monitored in the future. The results obtained are spatially contrasting and stable, and show that such techniques can be used on a resistive medium of arid environments.

In Morocco, conservation agriculture, particularly no tillage systems, has become an alternative strategy to mitigate land degradation caused by conventional tillage in semiarid to arid regions. This paper is based on behaviour to tillage treatments of two Vertisols in Morocco. After 11 years of testing, soil organic matter content results showed a significant difference (P<0.05) only at soil surface (0–10 cm) in favour of no tillage and a variation of 30% at this depth. The results obtained after 32 years of testing showed a significant soil profile difference (P<0.05), up to 40 cm under no tillage compared to conventional tillage, and a variation of 54% at 5–10 cm. For total nitrogen, there was no significant effect between no tillage and conventional tillage at the soil surface after 11 years unlike the result obtained after 32 years. There are no significant differences in bulk density between tillage treatments at soil surface for both sites. The measurement of soil structural stability showed a significant effect (P<0.05) for all three tests and for both sites. This means that no tillage helped Vertisols to resist different climatic constraints, preserving environmental soil quality.

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RÉSUMÉObjectifs : Le travail présenté ici a pour objectif de décrire l'effet de la salinité sur la croissance et la distribution des principaux éléments minéraux chez le bananier. Méthodologie et résultats : L'étude de l'effet de la salinité a été réalisée sur deux variétés du bananier (Musa acuminata L), la grande naine et la petite naine issues de culture in vitro. Les variétés testées ont été combinées à quatre niveaux de chlorure de sodium (NaCl) à savoir : 0, 2, 4 et 6 grammes par litre (g/l). Les résultats ont montré la réduction de la biomasse aérienne et racinaire, une accumulation de potassium dans la partie aérienne et de sodium dans la partie racinaire, ainsi qu'une réduction d'absorption de calcium et de magnésium et une légère variation d'azote dès la concentration 4g/l. Une certaine tolérance aux sels a été notée chez la variété grande naine comparativement à la petite naine. Cette tolérance pourrait être liée à une bonne sélectivité vis-à vis du potassium. Les variétés étudiées se comportent comme des plantes exclusives. Conclusion et application de la recherche : Les caractéristiques ioniques de la variété de bananier, la grande naine, diffèrent de celles de la petite naine, Les résultats obtenus confirment que l'amélioration de la productivité des bananiers au Maroc ne peut être réalisée que par des travaux destinés à élaborer un matériel génétique adapté à partir de la variété grande naine. Le choix doit s'effectuer sur la base d'un grand nombre de caractères (morphologiques, biochimiques physiologiques) contrôlant les déterminismes génétiques complexes de la tolérance à la salinité. ABSTRACTEffect of salinity on the growth of two varieties of banana Grande Naine" and "Petite Naine " and their mineral nutrition in Morocco Objectives: The present work is intended to describe the effect of salinity on the growth and distribution of major minerals in banana. Methods and results:The study of the effect of salinity was carried out on two banana varieties (Musa acuminata L), the grand Naine and the petite Naine from in vitro culture. The varieties tested were combined with four levels of NaCl (0, 2, 4 and 6 gal / l). Results showed the reduction of biomass and root accumulation of potassium in the shoot and sodium in the root. There was reduced absorption of calcium and magnesium and a slight variation from the nitrogen concentration of 4g / l. Some salt tolerance was noted in the Grande Naine compared to the petite Naine variety. This tolerance may be associated with a good selectivity towards potassium. Conclusion and application of research: ionic characteristics of the banana variety, the Grande Naine differs from the petite Naine. The results confirm that improvements in the productivity of banana in Morocco should be achieved by work to develop Grande Naine germplasm by the use of a large number of characters (morphological, biochemical, physiological) controlling complex genetic determinism of salinity tolerance

This study was carried out to assess the effect of the incorporation of detoxified argan press cake on milk yield, physicochemical composition, and microbial quality of raw Alpine goat milk produced in the Meskala-Essaouira region of southwestern Morocco. The detoxification method, adopted for the removal of saponin present in the argan press cake, succeeded in reducing these antinutrients from 4.56 to 0.4 mg/g, allowing it to be used as livestock feed. The average of milk production increased by 24% for the detoxified argan press cake (DAPC) group compared to the argan press cake and local diet groups. The diets and lactation stages had a significant effect (P < 0.05) on fat, protein, total solids, and salt in milk. Lactation stage and diet also had a significant effect (P < 0.001) on saponin concentrations in goat milk. Microbiological analysis showed that microbial flora of raw goat milk samples decreased with lactation stage. In terms of performance, DAPC could replace a conventional diet for goats without substantial detrimental effects.

Hydrophilic carboxyl‐containing fluoromembranes were obtained by preirradiation grafting of acrylic acid onto ethylene‐tetrafluoroethylene film. The dependence of the grafting reaction on temperature, monomer concentration, nature and concentration of inhibitor, crosslinking agent, solvent, and on the preirradiation dose was investigated. The grafting rates increase with temperature, whereas the saturation degree of grafting (SDG) decreases. Addition of inhibitor minimizes homopolymerization and at the same time hinders the grafting reaction. The SDG increases markedly with monomer concentration until it reaches a maximum and thereafter decreases. The grafting rates increase with preirradiation dose. Addition of crosslinking agent initially decreases the SDG, and thereafter increases. The highest grafting rates are obtained using water as solvent followed by methanol and ethanol. The results are discussed on the basis of various parameters: interaction between monomer diffusibility and the viscosity of the monomer bath, the mutual reactivity of monomer, and the crosslinking agent. An agreement is observed between the values of the electrical resistance and the saturation degree of grafting. © 1996 John Wiley & Sons, Inc.