RESUMO
Land degradation and soil erosion are becoming increasingly problematic in Africa's rapidly developing urban areas, particularly in Major Port Cities. Uncontrolled expansion and human pressures are hindering planning, adaptation, and conservation efforts. To understand the extent of these issues, this study combined morphometric analysis, soil loss calculation, field monitoring, and remote sensing and GIS tools to assess soil erosion in the Metropolis of Tangier (Morocco) located at the confluence of the Mediterranean Sea and the Atlantic Ocean at the Strait of Gibraltar. The study relied on data from 13 rain gauge stations, official reports, and remote sensing acquisitions, as well as field observations. Results showed an average soil erosion rate of 24.2 t/ha/year, equivalent to an annual soil loss of 588,051 t/year. This high rate was largely due to areas with a high erosion risk (99.8%), covering only 8.3% of the territory, which were characterized by recently burned topsoil, fallow land, and steep slopes. These areas included both uncontrolled neighbourhoods and areas for planned urban and industrial expansion, posing a threat to the landscape's sustainability and socio-economic prospects. The morphometric analysis revealed its high vulnerability to erosion and degradation, with the highest soil loss rates observed in the eastern and western regions. The study also found that flash floods caused by hydroclimatic hazards can lead to significant damage to infrastructure and equipment, particularly in western sub-basins and mountainous regions. In conclusion, the use of remote sensing and GIS technologies provided valuable insights into the physical characteristics and vulnerability of the Tangier Metropolis to land degradation and soil erosion. These findings emphasize the need for effective land management practices and conservation measures to mitigate the impacts of land degradation and soil erosion in the face of climate change. This information is crucial for decision-makers and stakeholders to develop strategies to address these pressing issues.
RESUMO
Science is the seed of a decent life, with which we sow hope in the present and which we irrigate with the perfecting of good deeds. It is even crucial in the Mediterranean southern frontiers where the cultural erosion dissolves the structure of a society abandoned by the arms and brains of its youth. Soil-water-vegetation crisis should not be underestimated; coupled with socioeconomic congestion it would lead to an irremediable crash. Here, we show that the first and most difficult step to face soil degradation is to cultivate the right idea and develop it into a well-established community culture. We found in northern Morocco that 94.5% of farmers have no qualification and 82.6% of them act in a way that worsens soil degradation even if they are aware of the severity of the problem. This confused perception of ideas originates inappropriate labour behaviours non-aligned with public actions. Our results show that the impact of this is a high potential regional erosion rate of 27.7 t/ha/year which is equivalent to a massive potential gross amount of soil loss of 44.3 Mt/year. We show that this leads to an overall vegetation decrease related mainly to the anthropogenic pressure then to climate and lithology. We anticipate that the solution must be comprehensive, participatory, strategic and innovative, led by education and scientific research (Citizen Science) and involving all actors equally. In its broad context, the only path to achieve the coordination and alignment of actions would be through a gradual change of perception and involvement based on a time-consuming culture of assimilation and acceptance rather than a culture of rapid reform.