The mineralization of urban soils facing the risk of climate change: Case of the flooding phenomenon in the city of Annaba

Abstract

Urbanization exerts changes on the environment and on the ecosystems and it leads to a modification of the nature of the soil or even a soil impermeability via the infrastructures carried out. This impermeability acts as an aggravating factor for the effects of climate change and causes local environmental stresses. These are particularly urban heat island and urban flooding. The city of Annaba (located in the northeast of Algeria) is among these dense coastal cities, which have experienced rapid and abrupt urban development resulting in the expansion of impermeable infrastructure at the expense of the removal of natural and vegetal cover. The problem of soil sealing in Annaba therefore put it face to face with the direct risk of climate change.Urban flooding is a phenomenon directly linked to soil sealing. The combined effects of climate change, in terms of changes in rainfall patterns and intensities, make some sewerage networks unable to evacuate increasingly large quantities of runoff water from impermeable surfaces causing important material and human damages. In fact, this city has experienced strong periods of heat in recent years, reaching 47°C in summer 2021 [1]. Winter was not so different, intense rainfall causes repeated flooding every year, amplifying the sensitivity and exposure of city dwellers and properties to multiple risks. The present consideration, aims to identify and measure sealed surfaces and to determine the areas vulnerable to the impacts of soil sealing.