Overexploitation of forests by humans can lead to highly fragmented populations of forest-dependent species that have poor dispersal abilities. We tested the influence of habitat quality, landscape structure and human pressure on densities of the Barbary macaque Macaca sylvanus in the largest wild population, in the Middle Atlas of Morocco.We surveyed 14 forest fragments of 5-142 km 2 that are separated from each other by an inhospitable matrix. We estimated the habitat quality of these forest patches by analysing the vegetation structure and the intensity of human pressure. We studied the distribution of forest patches and estimated macaque densities by combining line transect sampling and complete group counts. We estimated mean density of individuals to be 9 km -2 (range 0.2-23 km -2 ). Differentiation of forest patches by a Principal Component Analysis did not show any significant relationship between vegetation type and macaque density. A linear regression model showed that human pressure had a negative impact on density and that density responded positively to patch size. Patch shape, connectivity and altitude did not explain variation in population density. The size of this population is estimated to be c.5,000 individuals. The survival of several small subpopulations is seriously threatened. As the Middle Atlas is the stronghold of this Endangered species, we recommend modifying forestry practices, reducing overgrazing by livestock within forests and halting clearcutting of holm oaks.
The effect of abscisic acid (ABA) on callus growth and plant regeneration was studied in Four cultivars of durum wheat considered to have a good ability for in vitro culture. calluses induced from immature embryos on MS medium supplemented with 2 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) were transferred onto the same medium supplemented with different concentrations of ABA (0, 1, 2, 4 and 10 µM). The regeneration medium used was MS medium supplemented with 0.2 mg L-1 of 2,4-D, 10μM of benzylaminopurine (BAP) and 5μM of naphthaleneacetic acid (NAA). callus growth decreased with increasing concentration of ABA in the medium.Best regeneration rates were obtained from calli that were grown on media containing a low concentration of ABA (1 µM).The best number of plantlets per regenerating callus was also obtained from cultures on media containing 1μM ABA. Among the regenerated plants, some rare albino plants were obtained from calluses of Karim and Anouar varieties.
Macrophytes are one of the main components of the aquatic ecosystem. They are used in several countries as metrics for the ecological assessment of hydrosystems. The objective of our study was to evaluate the suitability of the Macrophyte Biological Index for Rivers (IBMR) to determine a trophic level in the upper Oum Er Rbia basin (Morocco) and to understand physicochemical parameters of water that govern the distribution of macrophyte species. CCA analysis was used to relate the distribution of macrophytes to hydrochemical parameters of water. The CCA analysis shows that the distribution of macrophytes was more correlated with abiotic parameters (EC, WT and DO) than nutrient parameters (PO4-P, NO3-N, NO2-N, NH3-N and CODMn). The recorded values of IBMR in the upper Oum Er Rbia basin indicate that the trophic level of the studied rivers ranged from “moderate” to “very high”. Pearson's correlation coefficient showed that the IBMR is more correlated with the abiotic parameters such as WT and EC and does not show any significant correlation with the content of PO4-P and NH3-N in water, which makes the IBMR index unreliable for assessing the trophic status related to phosphate and ammonia concentrations in our lotic waters.
Macrophytes represent a functional compartment that plays multiple and fundamental ecological roles in aquatic environments. They are linked with the other compartments of hydrosystems, both abiotic and biotic, which gives them the ability to integrate environmental conditions and reflect the trophic state of watercourses.Nevertheless, macrophytes in Moroccan rivers have been rarely studied. Thus, the main objective of the present work is to study these plants by determining the environmental factors that control their presence and distribution in the watercourses of the upper Oum Er-rbia basin (Middle Atlas Morocco). From June 2018 to June 2019, 14 sites spread over five rivers were monitored monthly to describe macrophytic communities and investigate their ecological determinism. We used a principal component analysis to establish each river's typology and a detrended correspondence analysis to explore macrophyte assemblages. Canonical correspondence analysis was used to determine the hydrochemical parameters of water that govern the development and distribution of macrophyte species in the upper Oum Er-rbia basin. The Amengous river stands out from the other surveyed rivers for its exceptional richness of macrophytic species. This richness is often associated with the enrichment of the aquatic environment by nitrogen and phosphate inputs. Furthermore, in some rivers, such as Oum Er-rbia, nutrient enrichment plays a secondary function in comparison to the hydromorphological descriptors that tend to be more important for macrophyte composition and distribution.
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