Soil health in Moroccan olive agroecosystems: The bioindication role of terrestrial nematode dynamics

Terrestrial nematodes are important soil microorganisms that modulate biological processes in soil ecosystems. Thus, these microorganisms have strong potential as soil health bioindicators. This study aimed to investigate their distribution patterns in Moroccan olive agroecosystems and to evaluate their structural and functional dynamics shaping soil disturbance status. An extensive survey was conducted across 65 representative olive fields (orchards and nurseries combined) located in 7 distinct regions during the 2023 season. For each region, several indices were calculated to assess nematode biodiversity alongside their involvement in soil food web diagnostics. The results revealed 63 nematode genera that were detected and classified into different trophic groups: 21 bacterial feeders, 7 fungal feeders, 6 omnivores, 6 predators, and 22 plant feeders. Most soil ecosystems showed low to moderate disturbance with maturing food web conditions, whereas a few showed notable soil disturbance with bacterial and conducive properties. Structural and functional dynamics revealed that both bacterial and plant feeders effectively contributed to undisturbed and disturbed soils, respectively. This study provides novel insights into the biodiversity and dynamics of terrestrial nematodes associated with Moroccan olive agroecosystems and their contribution as effective soil health bioindicators

Evaluation of groundwater quality and agricultural use under a semi-arid environment : case of Agafay, Western Haouz, Morocco

Water resources are a priority for economic development, aiming at meeting the increasing needs of agriculture and all socio-economic sectors. Agriculture is one of the essential pillars of this development in the Haouz Plain. Under a semi-arid climate, irrigation, consuming more than 85% of available water, is inevitable for most crops. Hence, groundwater is becoming increasingly under pressure. Salinization due to poor irrigation management is one of the main causes of soil degradation. In this context, assessment of groundwater quality and risks of soil salinization was carried out in irrigated citrus orchards located in the western part of Haouz and aimed at understanding the connection between natural context, irrigation practices, and water and soil salinization. The spatial distribution of aquifer potential lines is affected by groundwater over-exploitation. Moreover, geologically, the Palaeozoic substratum rise constitutes an obstacle for underground flow, which explains the low values recorded and measured around the studied area. The groundwater quality in the study area is characterized by strong mineralization, consequently affecting the soil by secondary salinization due to the intensive use of moderate saline waters from groundwater. Using a mixture of different water origins is a practical measure to reduce the risks of degradation of the soil