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EN
In order to optimize cork productivity in the Maamora forest, specifically in the northern part of the A, B, C, D, and E cantons, the study focused on the analysis and updating of the distribution of productive cork oak (Quercus suber L.) stands as well as the evaluation of cork production over the past two decades. For this purpose, the available maps were corrected and updated using GPS data and field surveys between 2019 and 2022. Similarly, a thorough examination of the archives related to cork harvesting from the water and forestry administration was conducted and enriched by data collection during the survey. The obtained results indicate that the productive area is approximately 39% of the total area in the study zone. Simultaneously, statistical data has highlighted significant fluctuations in the annual gross cork production, coupled with a concerning decrease of 21.29% during the second rotation. Indeed, during the second rotation, 30% of the productive area was not harvested, compared to approximately 14% during the first rotation. Similarly, only 59% of the productive area underwent two harvest cycles. Despite these fluctuations, the recorded productivity during the second rotation, at 0.68 stere/hectare/year, remains above the national average. The differences between cantons are also noteworthy, emphasizing the impact of local factors on cork harvesting. In this context, ensuring sustained cork productivity while ensuring the sustainability of vegetal capital against climate change requires the implementation of an adaptive management approach.
EN
Spontaneous flora offers many functions and potentialities in the urban ecosystem. However, few studies have been carried out on this subject in Morocco. The present study aimed to analyze the diversity of spontaneous flora in the urban area of Temara, to contribute to interpreting the structure and dynamics of Moroccan spontaneous flora. During the study, 90 floristic surveys were carried out along four transects, marked A, B, C, and D so that each transect started from the city center and went in one of the four directions of the study area. Transect A ran northwards from the city center, transect B westwards, transect C southwards, and transect D eastwards from the city center. To carry out the floristic surveys, several survey areas were chosen, given the heterogeneity of the urban environment. These areas ranged from a few cm2 for rock fissure plants, through 10 to 25 m2 for grasslands, to 25 to 100 m2 for forest cuttings. The results revealed a total of 137 taxa grouped in 116 genera and belong to 33 floristic families. The Asteraceae family came out on top, with 30 species (21.90%) and 24 genera, and the Poaceae family was in second place with 21 species (15.33%) divided into 20 genera. Analysis of this floristic list indicates a predominance of the therophyte life form (48.90%), then hemicryptophytes (26.28%) followed by geophytes (10.22%) in terms of biological type, and a predominance of the Mediterranean element (31.19%) in terms of chorological type. Of the 137 taxa inventoried, 10 are very rare, 1 is rare, 1 has a doubtful presence, and 2 are endemics. This study showed that even in a disturbed and fragmented environment, such as the urban environment, certain spontaneous plant species adapt to the conditions prevailing in this habitat and show considerable diversity, thus contributing to a better interpretation of the composition and dynamics of the country’s flora.
EN
The present study aims to compare two different methods for the determination of soil organic matter (SOM); the wet acidified dichromate oxidation methods Walkley-Black (WB) and the combustion’s one (mass loss on ignition – LOI); in order to find out the best one in terms of suitability, environmentally-friendly, time-efficiency and economical benefit. Forty-five Moroccan soil samples (El Guich, Koudia and Merchouche area) from 0–20 cm depth with different classes, textures and organic matter contents were evaluated. According to the results, a strong linear relationship was observed between LOI-OM and WB-OM methods for all the sites. However, El Guich and Koudia recorded much larger regression coefficients (0.745*** and 0.611*** respectively) compared to Merchouche site (0.452**). Therefore, the SOM by walkley-Black method can be easily calculated from the LOI method at 500±25 ºC for 2 hours using linear equation in order to minimize the analysis time and consumption of chemicals for routine laboratory. In addition, it was noticed that the SOM contents calculated by the LOI method are higher in Merchouche soils compared to that of WB due to the presence of a large amount of clay minerals in the Merchouche soils (43.9 < %clay < 56.1) in comparison with those of El Guich (5 < %clay < 7.5) and Koudia (16.1 < %clay < 20.4). This study revealed that both methods were reliable but W.B method was more accurate and suitable for calcareous soils and those with high clay contents. However, LOI method is an accurate and beneficial for non-calcareous soils with low clay content.
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